U.S. Department of 

Transportation 

Federal Railroad 

Administration

Stub Sill Railroad Tank Car Research Project: 

Full-Scale Damage Tolerance Test 

Office of Research 

and Development 

Washington, DC 20590 

DOT/FRA/ORD-07/25 Final Report 

 October 2007 

This document is available to the 

U.S. public through the National 

Technical Information Service, 

Springfield, VA 22161. 
NOTICE 

This document is disseminated under the sponsorship of the

Department of Transportation in the interest of information

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report. 

 
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Stub Sill Railroad Tank Car Research Project: Full-Scale Damage Tolerance Test DTFR-53-93-C-00001 

Task Order 108 

6. AUTHOR(S)

Kevin B. Smith 

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION 

REPORT NUMBER Transportation Technology Center, Inc. 

P.O. Box 11130 

55500 DOT Road 

Pueblo, CO 81001 

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 AGENCY REPORT NUMBER U.S. Department of Transportation DOT/FRA/ORD-07/25 Federal Railroad Administration 

Office of Research and Development 

1120 Vermont Avenue, NW 

Washington, DC 20005 

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This document is available to the public through the National Technical Information Service, 

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13. ABSTRACT (Maximum 200 words)

The Federal Railroad Administration, with supplemental support from the Association of American Railroads (AAR), Railway 

Progress Institute, and Chemical Manufacturers Association, contracted with the Transportation Technology Center, Inc., a 

subsidiary of AAR (then organized as AAR, Transportation Technology Center), to conduct a full-scale damage tolerance analysis 

(DTA) validation test on a tank car using the Simuloader. This is one of five companion reports that detail North American tank 

car industry efforts since 1992 to assess the operating environment and apply DTA principles to tank car design. These efforts

included an over-the-road operating environment survey, material spectrum variable testing, a full-scale fatigue crack growth test, 

fractographic analysis of the full-scale test vehicle, and DTA analytical model validation and application guidance. This 

document covers only the details of the 300,000-spectrum mile full-scale DTA validation test. 

14. SUBJECT TERMS 15. NUMBER OF PAGES

Damage tolerance analysis, tank car design, over-the-road, fatigue crack growth, full-scale DTA 220 

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 OF REPORT OF THIS PAGE OF ABSTRACT

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1 inch (in) = 2.5 centimeters (cm) 1 millimeter (mm) = 0.04 inch (in) 

1 foot (ft) = 30 centimeters (cm) 1 centimeter (cm) = 0.4 inch (in) 

1 yard (yd) = 0.9 meter (m) 1 meter (m) = 3.3 feet (ft) 

1 mile (mi) = 1.6 kilometers (km) 1 meter (m) = 1.1 yards (yd) 

 1 kilometer (km) = 0.6 mile (mi)

AREA (APPROXIMATE) AREA (APPROXIMATE) 

1 square inch (sq in, in2) = 6.5 square centimeters (cm2) 1 square centimeter (cm2) = 0.16 square inch (sq in, in2) 

1 square foot (sq ft, ft2) = 0.09 square meter (m2) 1 square meter (m2) = 1.2 square yards (sq yd, yd2) 

1 square yard (sq yd, yd2) = 0.8 square meter (m2) 1 square kilometer (km2) = 0.4 square mile (sq mi, mi2) 

1 square mile (sq mi, mi2) = 2.6 square kilometers (km2) 10,000 square meters (m2) = 1 hectare (ha) = 2.5 acres 

1 acre = 0.4 hectare (he) = 4,000 square meters (m2) 

MASS - WEIGHT (APPROXIMATE) MASS - WEIGHT (APPROXIMATE) 

1 ounce (oz) = 28 grams (gm) 1 gram (gm) = 0.036 ounce (oz) 

1 pound (lb) = 0.45 kilogram (kg) 1 kilogram (kg) = 2.2 pounds (lb) 

1 short ton = 2,000 pounds 

(lb) 

= 0.9 tonne (t) 1 tonne (t) =

=

1,000 kilograms (kg) 

1.1 short tons

VOLUME (APPROXIMATE) VOLUME (APPROXIMATE) 

1 teaspoon (tsp) = 5 milliliters (ml) 1 milliliter (ml) = 0.03 fluid ounce (fl oz) 

1 tablespoon (tbsp) = 15 milliliters (ml) 1 liter (l) = 2.1 pints (pt) 

1 fluid ounce (fl oz) = 30 milliliters (ml) 1 liter (l) = 1.06 quarts (qt) 

1 cup (c) = 0.24 liter (l) 1 liter (l) = 0.26 gallon (gal) 

1 pint (pt) = 0.47 liter (l) 

 1 quart (qt) = 0.96 liter (l) 

1 gallon (gal) = 3.8 liters (l) 

1 cubic foot (cu ft, ft3) = 0.03 cubic meter (m3) 1 cubic meter (m3) = 36 cubic feet (cu ft, ft3) 

1 cubic yard (cu yd, yd3) = 0.76 cubic meter (m3) 1 cubic meter (m3) = 1.3 cubic yards (cu yd, yd3)

TEMPERATURE (EXACT) TEMPERATURE (EXACT) 

[(x-32)(5/9)] °F = y °C [(9/5) y + 32] °C = x °F

QUICK INCH - CENTIMETER LENGTH CONVERSION

0 1 2 34

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Centimeters 01 3 2 6 4 5 7 1098 12

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5

11 13
iii 

Contents 

Illustrations.. ................................................................................................................................... v 

Tables........................................................................................................................................... vi 

Acknowledgements....................................................................................................................... vii 

Executive Summary........................................................................................................................ 1 

1. Background.................................................................................................................. 3 

1.1 Stub Sill Tank Car Research ....................................................................................... 3 

1.2 OTR Test ..................................................................................................................... 5 

1.3 Coupon Test Programs ................................................................................................ 6 

1.4 DTA............................................................................................................................. 9 

1.5 The Simuloader ......................................................................................................... 11

1.6 Test Car Description.................................................................................................. 13 

2. Objective.................................................................................................................... 15 

3. Initial Conditions....................................................................................................... 17

3.1 Physical Setup ........................................................................................................... 17

3.2 System Characterization............................................................................................ 23

3.3 Preliminary Analysis ................................................................................................. 24

3.4 Test Car Flaw Induction............................................................................................ 25 

3.5 Transducer Setup....................................................................................................... 26

3.6 Simulation Inputs ...................................................................................................... 33

4. Test Operations.......................................................................................................... 37

4.1 Crack Initiation.......................................................................................................... 37 

4.2 Spectrum Loading ..................................................................................................... 38

4.3 Mid-Test Procedure Adjustments.............................................................................. 40 

4.4 Post-Test Analysis..................................................................................................... 42

5. Results and Discussion.............................................................................................. 45

5.1 Spectrum Crack Growth............................................................................................ 45 

5.2 Carbody Compliance................................................................................................. 51

5.3 System Control and Response................................................................................... 58 

5.4 Post-Test Analysis..................................................................................................... 58

6. Significant Observations ........................................................................................... 61

6.1 OTR and Coupon Testing.......................................................................................... 61 

6.2 Orphan Tank Car NATX 22746................................................................................ 61 

6.3 Pre-Test DTA ............................................................................................................ 61

6.4 Preflawing and Precracking....................................................................................... 62 

6.5 Validation Load Schedule ......................................................................................... 62 

6.6 Marker Band Application.......................................................................................... 62 

6.7 Spectrum Crack Growth............................................................................................ 63 
iv 

6.8 Carbody Compliance................................................................................................. 63

6.9 VCF Placement and Amplification ........................................................................... 64 

6.10 DTA Validation......................................................................................................... 64

References..................................................................................................................................... 65 

Acronyms...................................................................................................................................... 67 

Glossary ........................................................................................................................................ 69 

Appendix A. Relevant Portions of SwRI 10,000-Mile Tank Car Load Schedule ..................... A-1 

Appendix B. Full-Scale Damage Tolerance Test Crack Indication Log .................................... B-1 

Appendix C. Piecewise Carbody Compliance Test Data........................................................... C-1 

Appendix D. Carbody Compliance Sensitivities ....................................................................... D-1 

Appendix E. Rainflow Cycle-Counted Drive and Response Data ............................................ E-1 
v 

Illustrations 

Figure 1. Coupon Test Setup at SwRI ........................................................................................... 7 

Figure 2. Marker Bands on Coupon Fracture Surface ................................................................... 8 

Figure 3. Schematic of Tank Car on Simuloader......................................................................... 12 

Figure 4. Test Car NATX 22746 Upon Arrival at TTC .............................................................. 17 

Figure 5. SS-II Critical Regions (SS-II Codes Indicated)............................................................ 19 

Figure 6. Test Car NATX 22746 on Simuloader......................................................................... 19 

Figure 7. B-End of Test Car, LCF Connection............................................................................ 20 

Figure 8. Schematic of VCF Attachment to Stub Sill.................................................................. 21 

Figure 9. B-End of Test Car, VCF Connection ........................................................................... 21 

Figure 10. VCF System Transfer Function.................................................................................. 23 

Figure 11. Basic Critical Region Structural and Weld Details .................................................... 25 

Figure 12. B-End Right Corner Flaw and Tank Head Rosette .................................................... 26 

Figure 13. B-End Left Strain Gages and Preflaw ........................................................................ 29 

Figure 14. B-End Right Strain Gages and Preflaw...................................................................... 30 

Figure 15. A-End Left Strain Gages ............................................................................................ 31 

Figure 16. A-End Right Strain Gages and Preflaw...................................................................... 32 

Figure 17. Sill Bending Strain Gages (at Both Ends of Car)....................................................... 32 

Figure 18. Segment of VCF Input Sinusoid................................................................................. 35 

Figure 19. B-End Seal Weld Cracks............................................................................................ 46 

Figure 20. B-End Left Flange Weld Cracks and Preflaw ............................................................ 46 

Figure 21. B-End Right Seal Weld Cracks and Preflaw.............................................................. 47 

Figure 22. A-End Left Seal Weld Cracks and Preflaw................................................................ 47 

Figure 23. A-End Left Sill Top Flange Crack ............................................................................. 48 

Figure 24. A-End Right Seal Weld Cracks.................................................................................. 48 

Figure 25. A-End Right Sill Top Flange Cracks.......................................................................... 49 

Figure 26. A-End Right Flange Weld Crack and Preflaw ........................................................... 49 

Figure 27. VCF Load Stud Fracture Surface at 6.6x Magnification............................................ 50 

Figure 28. Schematic of Potential LCF Load Path ...................................................................... 52 

Figure 29. Principal Stress Magnitudes and Directions at B-End Left Tank Head ..................... 55 

Figure 30. Principal Stress Magnitudes and Directions at B-End Right Tank Head................... 55 

Figure 31. Principal Stress Magnitudes and Directions at A-End Left Tank Head..................... 56 

Figure 32. Principal Stress Magnitudes and Directions at A-End Left Sill Web ........................ 57 
vi 

Tables 

Table 1. Orphan Tank (Test Car) Characteristics ........................................................................ 13 

Table 2. Orphan Tank (Test Car) Materials................................................................................. 14 

Table 3. Basic Simuloader Actuator Characteristics ................................................................... 22 

Table 4. Induced Flaw (Preflaw) Locations................................................................................. 25 

Table 5. Data Collection Channel List......................................................................................... 27 

Table 6. Validation Test Strain Gage Summary .......................................................................... 28 

Table 7. 10,000-Mile Validation Load Schedule Breakdown ..................................................... 35 

Table 8. Sequence of Significant Full-Scale Test Events............................................................ 37 

Table 9. Precracking Loads Applied in Full-Scale Test .............................................................. 38 

Table 10. Marker Bands Applied in Full-Scale Test ................................................................... 39 

Table 11. Empirical/Analytical Comparison Matrix Example .................................................... 41 
vii 

Acknowledgements 

The author of this report wishes to express his appreciation and thanks to Jose Pena, who acted 

as Task Order Monitor for the Federal Railroad Administration (FRA), as well as Dan Stone who 

acted as Damage Tolerance Analysis Program Manager for the Railway Progress InstituteAssociation of American Railroads Tank Car Safety Project. Helpful discussions were also held 

with Joe Cardinal and Pete McKeighan from Southwest Research Institute (SwRI) and Mike 

Williams from American Railcar Industries. 

In lieu of an exhaustive list of all individuals who influenced this project, the author would like 

to acknowledge all members of the Stub-Sill Working Group for their continuing program 

guidance and support. The author also notes the efforts of the lab crew, consisting of Dave 

Johns, Transportation Technology Center, Inc. (TTCI); Denzel Savage, TTCI; Mike Sandoval, 

TTCI; Tom Roderick, TTCI; Tom Masden, SwRI; and Dan Benac, SwRI. 

Additionally, FRA is acknowledged for its permission to use information from this test program 

for papers and presentations at professional societies. Joe Cardinal is also personally 

acknowledged for his direct contribution to this report with a detailed description of damage 

tolerance. 
viii 
1 

Executive Summary 

In 1992, the National Transportation Safety Board (NTSB) recommended that tank car structures 

be designed using a damage-tolerant philosophy similar to that utilized by the aircraft industry. 

Toward that end, the Southwest Research Institute (SwRI) was engaged to assist in the 

development and implementation of a damage tolerance analysis (DTA) methodology for 

railroad tank cars. To help validate the resulting methodology, the Federal Railroad 

Administration (FRA), with supplemental support from the Association of American Railroads 

(AAR), Railway Progress Institute (RPI), and Chemical Manufacturers Association (CMA), 

contracted with the Transportation Technology Center, Inc. (TTCI), a subsidiary of AAR (then 

organized as AAR, Transportation Technology Center (TTC)), to conduct a full-scale fatigue 

crack growth test on a tank car. This report is one of several that detail North American tank car 

industry efforts since 1992 to assess the operating environment and apply DTA principles to tank 

car design. These efforts include an over-the-road (OTR) environmental survey, coupon 

spectrum variable testing, a full-scale fatigue crack growth test, a fractographic analysis of the 

full-scale test pieces, and DTA analytical model validation and application guidance. This 

document covers only the details of the 300,000-spectrum mile full-scale DTA validation test. 

Before the full-scale test, a 15,000-mile OTR test was performed to enhance data for 100-ton 

tank cars published in the AAR Manual of Standards and Recommended Practices. This revised 

tank car data was used to create the 10,000-spectrum mile load schedule used in the full-scale 

test program, as well as for industry DTA models. Subsequent to this OTR test, a coupon test 

program was conducted to investigate effects of spectrum variables on fatigue crack growth 

rates. These preliminary coupon studies indicated that for accelerated tests of common tank car 

steels, the omission of relatively small cycles (truncation) and peak load attenuation (clipping) 

might have minimal effects on crack growth behavior. 

While the full-scale test was assembled, a finite element analysis (FEA) of the test car was used 

to find locations of high stress (critical regions), estimate stress-to-load ratios for truncation, and 

provide input into the crack growth model to estimate test duration. In general, the FEA 

predicted stress concentrations at the same critical regions identified by the SS-II database, a 

compilation of stub sill inspections performed by the tank car industry. However, the predicted 

stress magnitudes were understated by a nominal weighted-average factor ranging from one to 

three. This factor was an engineering estimate based on several measurements and many 

parameters and warrants further study. 

The orphan tank car used for the full-scale validation test had neither head pads nor head braces 

(details that are common to current tank car designs) and no previous record of parent metal 

crack repairs. Initial visual inspections of the car did not reveal any cracks in the more critical 

stub sill regions highlighted by both the SS-II database and the stress analysis of the car. For this 

reason, flaws were mechanically created in four critical regions and cyclic loading was used to 

initiate cracks from these preflaws. Though this precracking effort was only marginally 

successful at the preflaws, several unexpected cracks were initiated nearby within the critical 

regions of interest. 

The Simuloader, a computer-controlled servohydraulic test bed for full-scale multiaxial fatigue 

and vibration testing of rail cars, was used to perform the 300,000-spectrum mile full-scale DTA 

validation test. Longitudinal and vertical coupler forces (LCF and VCF, respectively) were 
2 

applied to the test car in series (without any corresponding bolster motions), and crack growth in 

critical regions was monitored. In addition, car body strains and deflections under static loads 

were periodically measured. These carbody compliance surveys showed variability in both 

linearity and repeatability, a likely result of stress redistribution throughout the structure due to 

crack propagation. In addition, upward vertical and draft longitudinal coupler loads were 

dominant in terms of critical region strain sensitivity, though the opposite loading directions are 

typically dominant for crack growth, as they usually cause critical region tension. 

Because this was a DTA validation, not an OTR simulation, many simplifications were utilized 

to simplify the modeling, accelerate the test, and reduce costs without compromising any 

program objectives. To accelerate the test, the input DTA load schedule was truncated to a small 

percentage of the OTR cycle count, though actuator transient response added many small cycles 

back into the test spectra. As a setup cost reduction, vertical loads were applied to the stub sills 

of the car just inboard of the strikers, rather than out at the coupler pulling face (as they are 

experienced in the field), which resulted in the understatement of the applied bending stresses. 

This changed at 200,000 DTA spectrum miles when the vertical coupler input spectrum was 

amplified to accelerate crack growth, which effectively corrected for the missing moment arm 

and doubled the applied shear (compared to OTR) in the critical regions. None of these 

simplifications compromised the validation effort, because the inputs into the car were identical 

to those into the analytical computer models (FEA and crack growth). The vertical loads were 

applied in the FEA at the same structural points as they were on the test car, and all loads were 

recorded during testing as input into crack growth models of the critical regions. Due to these 

simplifications, however, 300,000 DTA spectrum miles (the duration of the test) is not correlated 

with 300,000 revenue service miles of fatigue damage. 

By the end of the test, 30 crack indications (unconfirmed at that point) had been documented and 

monitored for surface growth; 5 of which were from preflaws. Ten of these cracks and two 

preflaws were broken open for a cursory fractographic analysis (through the thickness); three 

cracks and one preflaw were examined more thoroughly. The application of constant-amplitude 

marker bands proved to be effective for creating a record of crack growth rates and aspect ratios. 

The full-scale test and corresponding DTA results, though not directly transferable to other stub 

sill tank car designs, illustrated the general applicability of the damage tolerance approach to 

tank car design and life extension. Sufficient stress and crack growth results have been obtained 

for the DTA analytical model validation. 

 
3 

1. Background 

This report contains descriptions of the Simuloader, a full-scale multiaxial servohydraulic fatigue 

and vibration test machine for railcars, and DTA, a fracture mechanics-based methodology used 

to establish inspection intervals for fatigue cracked structures. This report concentrates on the 

use of the Simuloader to validate the DTA methodologies in the North American railroad tank 

car industry’s stub sill tank car research. After some evolution, Task Order 108 has been 

subdivided into three distinct, consecutive phases: 

1. OTR Operating Environment Survey 

2. Spectrum Variable Investigation with Coupon Testing 

3. Full-Scale Damage Tolerance Test 

Cogburn (1995) and McKeighan et al. (1997) provided detailed discussions of the first two 

phases in previously published reports; details from the third phase are the primary focus of this 

document and a companion report by Benac et al. (1998). Cardinal et al. (1998) discussed the 

actual DTA program performed in parallel with this task order, and Williams (1997) reported on 

the FEAs of the orphan tank car that was tested. 

Before the third phase of Task Order 108 is discussed, some background information on the 

various components of this multidimensional tank car research program has been assembled. 

Section 2.1 provides a historical perspective with a few of the events that have shaped decisions 

of both the tank car industry and FRA as the DTA program and Task Order 108 have evolved. 

Sections 2.2 and 2.3 briefly summarize some of the goals and relevant findings of the first two 

phases of Task Order 108. Sections 2.4 and 2.5 include general descriptions of DTA and the 

Simuloader. 

1.1 Stub Sill Tank Car Research 

1.1.1 Tank Car Damage Tolerance 

Throughout the first half of the 20th century, the prevailing design for railroad tank cars 

employed a continuous center sill, above which a tank was mounted. In the late 1950s, the stub 

sill design was introduced in which short draft sills were welded onto each end of the tank (thus, 

coupler loads were transmitted through the tank itself). Because a large portion of the sill weight 

was eliminated, the stub sill design proved to be more efficient than that of the through sill. With 

this improved efficiency, stub sill tank cars rapidly became preferred by the industry and soon 

came to dominate the North American tank car fleet. During the early 1990s, at least 12 sill 

separations occurred in this fleet of stub sill tank cars. A resulting inspection of 1,100 cars 

showed fatigue cracking at the attachment of the sill to the tank in a significant number of these 

designs. At that time, the North American railroad tank car industry agreed to inspect and repair 

stub sills and their attachment welds on all tank cars built before 1984. 

At the same time, the tank car industry agreed to undertake a DTA program to establish safe 

inspection intervals for the newly repaired cars. Toward this end, a technical committee was 
4 

formed, including several individual car builders and owners, FRA, AAR, RPI, CMA, and 

Transport Canada. This committee employed SwRI to act as an independent third-party program 

manager providing guidance during the industry’s adoption of DTA principles. This committee, 

hereafter referred to as the Stub-Sill Working Group (SSWG), reports to the AAR/RPI Tank Car 

Committee. In addition to Cardinal et al. (1998), Stone et al. (1997) has documented the efforts 

of SSWG. Hattery et al. (1997) discussed FRA support for industry-led projects to refine and 

use DTA techniques to ensure tank car reliability. 

1.1.2 Task Order Evolution 

From 1990 to 1993 under contract DTFR53-82-C-00282, Task Order 43, FRA funded the AAR 

Transportation Test Center (which has since privatized as TTCI) to study fatigue crack growth in 

stub sill tank cars. Cackovic et al. (1993) used the Simuloader to replicate 300,000 miles of 

fatigue significant service on a stub sill tank car. The fatigue loads simulated were obtained by 

combining tank car bolster vibration waveforms recorded during an OTR test with coupler loads 

measured during the Freight Equipment Environmental Sampling Test (FEEST). This 

combination was based on the assumption that coupler forces experienced in revenue service 

were typically incoherent (linearly unrelated at frequencies of interest) with truck bolster 

motions. Though no formal report was issued for the FEEST program, some details can be 

found in papers by Richmond et al. (1981) and Sharma et al. (1984). The data obtained from the 

FEEST program was published as Road Environment Percentage Occurrence Spectrums 

(REPOS) in Chapter VII of Specification M-1001, part of the AAR Manual of Standards and 

Recommended Practices (AAR-MSRP). 

In 1992, while the tank car industry embarked on a program of stub sill tank car inspections and 

DTA training, FRA, under contract DTFR53-93-C-00001, awarded Task Order 108: Stub Sill 

Tank Car Research. This contract was divided into three phases; the first of which was to 

determine the OTR environmental loading spectrums for a representative stub sill tank car. The 

data obtained in this phase was used to augment the existing FEEST data for 100-ton tank cars, 

as well as to provide input for the latter 2 phases of the task order and the tandem DTA program 

in progress. In 1995, the resources for the second phase (the squeeze test) were reallocated to 

investigate the effects of two spectrum variables (truncation and clipping) on fatigue crack 

growth in a coupon test program at SwRI. 

The Simuloader test (the third phase of Task Order 108) was originally planned to be an 

accelerated full-scale multiaxial fatigue test of the tank car used in the OTR test. However, 

much had developed since the inception of the program. The scope of this final phase was 

changed and expanded to validate the DTA methodologies under industry evaluation. An orphan 

tank car was located, instrumented, and mounted on the Simuloader. The LCFs and VCFs from 

the modified REPOS tables were input into the carbody sequentially for a period corresponding 

to approximately 300,000 miles of fatigue significant revenue service; no other actuators were 

used to apply loads to the car. Critical region stresses and crack growth rates were monitored 

throughout the test and have been compared to analytical predictions by Cardinal et al. (1998) for 

the actual DTA validation. 
5 

1.2 OTR Test 

1.2.1 Motivation and Results 

A complete recount of the motivations behind the operating environment survey (the first phase 

of Task Order 108) that began in 1994 is beyond the scope of this report; however, a brief 

summary is appropriate. Before 1988, the environmental load data used for tank car design was 

contained in fatigue analysis guidelines from a previous AAR study by Przybylinski et al. 

(1977). This road test data, collected in 1970, was processed with range-mean cycle counting 

methods and reported a maximum VCF of 12.5 kilopounds (kips). In 1988, this spectra was 

replaced with the FEEST data from 1986, which was processed with relatively more 

conservative rainflow cycle counting techniques and reported VCF events as high as 50 kips. 

Following this change, the relatively high load levels and the overall repeatability of the FEEST 

program were questioned. As a result of this questioning, the OTR test of 1994 was conceived. 

A side benefit of the 1994 OTR test was the vertical coupler load investigation that was launched 

during the instrumentation of the test car. The VCF measurement was originally designed to 

repeat the configuration used in the 1986 FEEST program. However, the setup was enhanced to 

determine whether more accurate VCF loads under both static and dynamic conditions could be 

obtained. The resulting five measurements of vertical coupler loading used the following strains, 

calibrated to force: 

• Coupler shank shear strain 

• Vertical sill bending strain 

• Striker/carrier strain 

• Yoke support plate shear strain 

• Vertical sill shear strain 

For reasons discussed by Cogburn (1995), vertical sill shear became the measurement of choice 

for the tank car design guidelines. This measurement, the data from which has subsequently 

been published in the AAR-MSRP, is not a direct measurement of VCF. Rather, it represents the 

vertical force acting at the striker/carrier resulting from a load applied at the coupler pulling face. 

The following five primary load cases measured in the 1994 OTR testing duplicated those of the 

earlier FEEST program: 

• Vertical center plate force 

• Vertical bolster force 

• Vertical side bearing force 

• LCF 

• VCF 

The side bearing load cells failed early in the test and were neither repaired nor replaced, as it 

was determined to be cost prohibitive given the relative importance of the measurement. 

Effectively, this meant that the center plate measurement was also abandoned because it was 
6 

calculated from the difference between the bolster load and the total side bearing load. The 

effect of this decision was realized when the data was integrated and published. 

1.2.2 Data Integration and Publishing 

The rainflow cycle-counted data acquired during the 1994 OTR test was reviewed and integrated 

into the AAR-MSRP with the 1986 FEEST data for 100-ton tank cars in general service. The 

most recently published version of these REPOS tables includes data from both test programs. 

As discussed in the previous section, the 1994 test failed to produce the vertical side bearing and 

the corresponding vertical center plate spectrums; therefore, the REPOS tables now contain only 

1986 data for both of these load cases. Because one of the primary goals of the 1994 test was to 

replace the questionable 1986 VCF spectrum, the AAR-MSRP now contains only 1994 data for 

VCF. The remaining two load cases, vertical bolster force and LCF, are represented with a 

combination of both the 1986 and 1994 data. The following describes the motivation behind this 

decision for the case of LCF. 

Stress-life fatigue calculations were performed in 1996 to qualify the relative differences 

between the 1986 and 1994 LCF spectra. Through these, it was demonstrated that absolute 

differences are extremely difficult to quantify due to the logarithmic nature of fatigue and the 

dependency of the calculations on variables, such as stress concentrations, material properties, 

and processing effects. Relative differences are much easier to characterize. The calculations 

showed that, in general, the loaded car data from 1986 is more conservative (more severe) than 

that of 1994. In contrast, similar calculations showed a reverse trend for the empty car data (the 

spectrum from 1986 was less conservative than that of 1994). To complicate matters further, the 

spectrum from 1986 was clipped at 300 kips draft and 500 kips buff (due to data acquisition 

limitations concerning the total number of bins allowable), thus reducing its potential severity. 

Ultimately, the decision was made to combine the spectra from 1994 with that of 1986 for the 

AAR-MSRP REPOS tables. 

1.3 Coupon Test Programs 

1.3.1 Truncation and Clipping Effects 

The spectrum variable investigation (the third phase of Task Order 108) was launched shortly 

after the completion of the OTR test in late 1995. To a large extent, a paper written by Orringer 

(1994) originally prompted the investigation into simulation acceleration techniques. An 

underlying assumption in accelerated simulation work is that a large percentage of revenue 

service data consists of load levels that do not produce fatigue-significant structural stresses. 

Whether this concept of a stress threshold applies in the case of fatigue crack growth is the 

subject of many debates. The determination of a threshold stress level for typical tank car steel 

was the primary purpose of the coupon testing program run by McKeighan et al. (1997). 

Toward this end, seven test specimens were machined from normalized ASTM A572 Grade 50 

steel from the remnants of stub sill production at Union Tank Car Company and tested with the 

loaded VCF spectrum from the 1994 OTR test. The two main parameters that varied for this 

study were the number of low amplitude cycles omitted (truncated) from each spectrum pass and 

the stress-to-force scale factor for the spectrum. This scale factor results from the fact that the 
7 

fatigue spectrums for this program were recorded in terms of a force applied at a relatively 

remote point on the structure from where the critical stress responses (thus, fatigue) actually 

occur. In addition to this study of truncation, a brief study into the effects of clipping was 

performed in parallel with the same coupons. Clipping differs from truncation in that load cycles 

are not removed from the input spectrum; rather, their individual magnitudes are limited to (not 

allowed to exceed) a preset value. Figure 1 is a photograph of the coupon test setup at SwRI. 

Figure 1. Coupon Test Setup at SwRI 

This preliminary study indicated that load cycles producing critical region stress ranges of less 

than 5.1 kilopounds per square inch (ksi) do not appear to contribute to crack growth and can be 

removed from the spectrum as a means of accelerating the test. In addition, tensile and 

compressive peak load clipping did not affect coupon life significantly outside the bounds of 

normal specimen variability. These conclusions were based on limited testing, and a more 

rigorous coupon test program was recommended for achieving more definitive conclusions. For 

the purposes of validating the analytical damage tolerance methodology, however, truncation 

was deemed an acceptable test acceleration method, and clipping was deemed tolerable, provided 

that identical load spectra are input into the analysis and the test article. 
8 

1.3.2 Marker Banding Feasibility 

For the DTA model validation, accurate crack length measurements during the full-scale test 

were crucial. Toward this end, a technique was utilized to supplement the visual inspection 

methods. The technique is referred to as marker banding and has been used for many years 

during full-scale and laboratory aircraft testing to ensure accurate post-test measurements of both 

crack length and aspect ratio. Fracture surface marking in the form of thin bands can be 

achieved with the application of a block of constant-amplitude cycles interspersed periodically 

throughout variable amplitude spectrum loading. 

Before the setup of the full-scale test, a laboratory coupon was manufactured from representative 

tank car steel, and potential fracture surface marking techniques were tested. A coupon of 

ASTM A572 Grade 50 steel (left over from the previous coupon studies) was loaded with the 

same spectrum used for the truncation studies, with periodic marker bands applied. To achieve 

marking, constant-amplitude periodic marking cycles were applied at a maximum of 90 percent 

of the peak spectrum load and a load ratio (minimum/maximum load) of 0.8. For this feasibility 

study, the number of marking cycles varied from 38,000 (the initial band) to 1,000 (the final 

band), so as to apply marks on the fracture surface approximately 0.004-inch wide. Figure 2 is a 

photograph of the coupon fracture surface at the conclusion of testing. 

Marker

Bands

Figure 2. Marker Bands on Coupon Fracture Surface 
9 

The preliminary study into marker banding feasibility was successful. The technique was 

optimized (i.e., the necessary cycle count, load magnitude, and load ratio were estimated), based 

on the results of the coupon test, for use in the full-scale test. In addition to band-application 

optimization, the potential benefits and drawbacks of two different load sequence scenarios (in 

this case, minimum-ordered versus mean-ordered) were evaluated. For this specific case, it was 

found that the order of the loads within a single spectrum pass had little effect on whether the 

marker bands were discernible on the fracture surface. Both studies were carried out to increase 

the likelihood of accurate crack length and depth measurements in the event that a crack tip was 

not clearly visible at the surface (due to geometry, rust, and weld surface complexity). 

1.3.3 Preflaw and Dye Penetrant Verification 

A crack induction methodology was planned to provide the necessary cracks to propagate for the 

DTA validation because the initial visual inspections of the orphan test car did not reveal any 

cracks in the regions of interest. This methodology consisted of the insertion of a notch (with a 

rotary grinder) near a stress concentration and the application of constant-amplitude cyclic 

loading to the specimen to initiate cracking from a corner of the new flaw. These processes are 

referred to as preflawing and precracking, respectively. Before the full-scale test began, this 

methodology was benchmarked against more reliable but less portable approaches (e.g., 

electrical discharge machining) with another coupon test. In addition, the use of dye penetrant 

was investigated and determined to have little effect on the readability of the fracture surface. 

1.4 DTA 

1.4.1 General Approach 

For many years, DTA principles have been used in the aircraft industry to establish structural 

lifetimes and determine safe inspection intervals; these are now being adapted for the analysis of 

stub sill cracks in railroad tank cars. These principles are well documented in a number of 

handbooks and textbooks (Gallagher et al., 1984; Broek, 1989; Barsom et al., 1987; 

DOT/VNTSC/FAA, 1993). A more complete description of the parallel DTA efforts that have 

guided the development of Task Order 108 is contained in the companion report by Cardinal et 

al. (1998). The philosophy, assumptions, and procedures for performance of a DTA, however, 

have been synopsized from this report in the following paragraphs. 

A number of specific technology areas comprise the DTA to structural integrity. As a result, 

performance of a DTA is a multidisciplinary effort requiring inputs from a diverse but related 

number of fields, including load spectra and stress analysis, fracture mechanics and fatigue crack 

growth analysis, laboratory and full-scale testing, nondestructive evaluation, and field 

experience. 

Damage tolerance can be defined as the capability of a structure to resist failure and continue to 

operate safely with damage (e.g., fatigue cracks) in the primary structure. The goal of a DTA is 

to demonstrate that structural integrity will be maintained for a designated or desired amount of 

time using some measure of life (hours, cycles, or miles). This goal is accomplished by 

computing fatigue crack growth curves and critical crack lengths for different critical locations in 

the structure. These calculations are subsequently used, along with nondestructive inspection 

sensitivity levels, to determine inspection intervals. 
10 

DTAs are based upon the supposition of pre-existing flaws, idealized as planar fatigue cracks, in 

the structure. Most fatigue cracks in welded joints can be represented in this fashion. For new, 

unused structural elements, an initial flaw size representative of manufacturing quality is 

specified. Initial flaw sizes for in-service structural elements are based on the resolution of the 

inspection technique. Flaws are presumed to exist at the worst locations (usually regions 

containing stress concentrations) in the structure; these areas are typically referred to as fatigue 

critical locations. The two primary sources of information used to identify these critical areas are 

field data and the results of global and fine-mesh FEA. 

Performing a crack growth calculation for a fatigue critical location requires the availability of 

three types of data: the load (stress) history, material and crack growth properties, and the 

assumed crack geometry along with its local stress field. To determine internal loads and 

stresses caused by remotely applied operational loads, global (coarse grid) and local (fine grid) 

FEAs are usually required. From these analyses, the stress gradient normal to the plane of 

anticipated crack growth is determined and used as input to a solution for the stress intensity 

factor (crack driving force) for a specific geometry and loading. The fatigue crack growth 

prediction methodology uses the stress intensity range, which is the variation of the stress 

intensity factor during a stress cycle. The stress intensity factor, K, is generally expressed as a 

function of the nominal far-field stress, σ, a geometry and loading mode dependent factor, β, and 

the crack length, a, as follows: 

K = βσ(πa)1/2

Geometry factor solutions (tabulated values or empirical expressions) for many structural 

geometries and loading conditions are available in fracture mechanics literature. They have also 

been incorporated into crack growth analysis software, such as NASGRO (Forman et al., 1994), 

originally developed by the National Aeronautics and Space Administration for the ongoing 

Space Shuttle Program. 

For computation of crack growth, a number of equations are available relating stress intensity 

range, ΔK, to crack growth rate, da/dN. The appropriate growth law used in an analysis is 

chosen based on the amount and rates of growth anticipated, the extent of available empirical 

data and how well the chosen model represents the empirical crack growth data. For structural 

steels, the Paris equation is often deemed to be suitable (Hudak et al., 1985): 

da/dN = CΔKm

The Paris coefficient, C, and the exponent, m, can be based on material properties and the degree 

of conservatism required by the application. Several crack growth expressions have been 

incorporated into software to predict crack growth under specified stress histories (or variable 

amplitude stress spectra). 

Crack growth analysis predicts growth but does not specify when a crack will become critical. 

The computation of critical crack length, acr, is accomplished with a substitution of the material’s 

fracture toughness (resistance to unstable fracture), Kc, into the stress intensity factor equation 

and solving for the critical crack length. Thus, with the crack growth curve and the critical crack 

size defined for a particular fatigue critical location, safety limits can be obtained. The initial 

safety limit is defined as the time required for a crack to propagate from a manufacturing flaw 

size to a critical crack size. The field safety limit is defined as the time required for a crack to 

grow from a detectable flaw size to a critical crack size. 
11 

Damage tolerance results (crack growth curves) must be transformed into specified inspection 

intervals that can be incorporated into a maintenance program. The basic concept is to provide a 

safety factor of two (or more) on life for the structural integrity of the component. This is 

accomplished by considering two categories of inspections: the initial inspection and subsequent 

in-service inspections. Assuming a safety factor of two, the initial inspection interval would be 

half of the initial safety limit. Likewise, recurring inspection intervals (in service) would be half 

of the field safety limit, specified by nondestructive evaluation techniques and reliabilities along 

with the corresponding detectable flaw sizes. 

1.4.2 Industry Progress 

For the specific application of DTA to tank car stub sills, SSWG has assembled the Stub Sill 

Inspection Database (AAR/RPI, 1996), hereafter referred to as the SS-II database. This 

database, based on the tank car fleet currently in service, has documented the locations of 

frequently occurring cracks. SwRI performed statistical analyses of this database to prioritize the 

severity of various fatigue critical locations in different car designs. In addition to providing 

input for this database, each of the RPI members of SSWG have proceeded with a preliminary 

DTA on at least one car design with guidance from SwRI. The full-scale test results have been 

used by Cardinal et al. (1998) to adjust some of the input parameters (both to the FEA and 

NASGRO portions of the process) that will be recommended for future DTA efforts. 

1.5 The Simuloader 

1.5.1 General Description 

The Simuloader is a computer-controlled servohydraulic test bed built for the full-scale 

multiaxial fatigue and vibration testing of railcars. Through the input of longitudinal and vertical 

forces into the center sill of a test vehicle (through solid load transfer blocks), as well as vertical 

and lateral displacements into a truck bolster interface underneath the vehicle, this machine can 

excite a test car with profiles and waveforms that represent an actual railroad environment. 

Simulations are typically done in an accelerated fashion with the utilization of only those events 

that produce significant stresses on the structure, combined with an overall compression of 

events in time. 

Originally donated to FRA in 1983 by Union Tank Car Company, the Simuloader was later 

installed at TTC in Pueblo, CO, which TTCI now operates. Manufactured by MTS Systems 

Corporation, this test system includes 13 hydraulic actuators of various capacities and their 

associated analog controllers. An IBM computer is used, in conjunction with a panel of 

Measurements Group signal conditioning amplifiers and a VXI-based chassis of digital/analog 

and analog/digital converters, to send drive signals to the controllers and collect actuator and test 

vehicle response data from up to 64 transducers. Figure 3 shows a schematic drawing of a tank 

car mounted on the Simuloader. 
12 

Figure 3. Schematic of Tank Car on Simuloader 

1.5.2 Evolution and Function 

Historically, freight car bodies and components were overdesigned to minimize in-service 

fatigue failures. High safety factors were used to keep stress levels in critical locations at a 

minimum. Increased fuel costs, combined with competition from the trucking industry in recent 

decades, however, have made these heavy designs uneconomical. The resulting design 

optimization effort created the need for accelerated fatigue testing of prototypes. 

Controlled laboratory environments have been available for the fatigue testing of relatively small 

components, such as truck bolsters and brake beams. The Simuloader was built to meet the need 

for a facility where a multiaxial fatigue test of an entire car body could be performed. This 

machine has been used by various car builders to verify analyses, reveal design deficiencies, test 

design modifications, and provide safety from fatigue failures not accounted for in standard 

specification testing. In a typical test, the effects of 30 years of fatigue damage can be simulated 

within a few months. 

1.5.3 Input Drive Files 

Drive files are computer data files that contain waveforms (time histories) used to animate the 

Simuloader and simulate the environment to which a particular freight car will be subjected over 

the course of its life. To date, simulation inputs have been created from various combinations of 

two sources of data: actual time history data and rainflow cycle-counted data. 

To obtain time history data, a manned instrumentation car is sent with an instrumented test car 

over an applicable route. Due to the expense involved, a test of this nature is usually only about 

2,000-miles long. Data from vertical and lateral accelerometers on the truck bolsters, strain gage 

bridges on the couplers, and a variety of carbody response transducers are recorded continuously 

over the route. After the uneventful miles are edited out (the process of truncation), the 

remaining bolster accelerometer time history data is double integrated into displacement signals 

to drive the Simuloader bolster modules, and the remaining coupler strain data is scaled into 

force signals to drive the solid load blocks. The primary advantage to this type of testing is that 

the sequence and phase relationships between the various inputs to the carbody are preserved. 

Sharma (1990) demonstrated this methodology. 
13 

Rainflow cycle-counted data (Society of Automotive Engineers, 1988), though typically only 

used for analytical fatigue studies, can be used to create sinusoidal time histories to drive the 

center sills of a car on the Simuloader. In this case, an unmanned data collection system is 

attached to an instrumented test car and sent over several applicable routes. Because rainflow 

data takes comparatively less computer memory storage space (thus, the cost of acquiring it 

greatly reduced), these tests are often on the order of 15,000-miles long. Force-calibrated strain 

gage bridges are used to collect truck bolster and coupler loads. Additional carbody response 

transducers are used in known critical regions. Though sequence and phase information is lost in 

this latter scenario, a better statistical sample of the carbody inputs can be obtained. It is 

believed that train handling is more representative of normal conditions when the crew is 

unaware of a test car in the train, as is usually the case with unmanned tests. AAR has tested 

several carbody designs extensively in this manner (Sharma et al., 1984) and compiled a 

database of the results in the AAR-MSRP. The data used for the Full-Scale Damage Tolerance 

Test was rainflow cycle counted. 

1.6 Test Car Description 

The tank car that was used for the full-scale DTA validation test was an orphan (the 

designer/builder is no longer in business) of stub sill design with about 300,000 miles of 

accumulated usage. The tank car had been in storage for approximately 8 years before being 

pulled for this program. When General Electric Capital Railcar Services (GE) donated the tank 

car to the program, it had neither head braces nor pads and had no previous record of parent 

metal crack repairs. Tables 1 and 2 provide a listing of the test car and material characteristics of 

interest. 

Table 1. Orphan Tank (Test Car) Characteristics 

Category Data

Date of Manufacture October 1967 

Classification DOT 111, Exterior Coiled and Insulated 

Car Number NATX 22746 

Length Over Strikers 51 feet X 11 3/8 inches 

Length Over End Sills 51 feet X 7 7/8 inches 

Length Over Tank Heads 49 feet X 3 5/8 inches 

Length Over Tank Seams 44 feet X 2 5/8 inches 

Length Over Truck Centers 39 feet X 11 3/8 inches 

Height X Rail to Jacket Top 12 feet X 1 7/8 inches 

 Height X Extreme (to Platform Handrail) 14 feet X 11 7/8 inches 

Outer Tank Diameter 104 inches 

Total Capacity 20,670 gallons 

Light Weight 75,000 pounds 

Gross Rail Load (Full) 263,000 pounds 

Truck Characteristics 100-ton, D3 Springs, and Roller Side Bearings 
14 

Table 2. Orphan Tank (Test Car) Materials 

Category Data

Sill Web Material AAR M116-Grade A Steel (Analogous to ASTM A7) 

Sill Web Thickness 5/8 Inch Specified, 19/32 Inch Measured 

Sill Top Flange Material ASTM A285 (Reportedly) 

Sill Top Flange Thickness 5/8 Inch Specified and Measured 

Tank Head Material ASTM A515-Grade 70 (Reportedly) 

Tank Head Thickness 1/2 Inch Specified and Measured 
15 

2. Objective 

The objective of the full-scale damage tolerance test was to experimentally validate the 

analytical damage tolerance methodologies under the consideration of SSWG. In this test, a stub 

sill tank car was subjected to the LFCs and VCFs normally experienced in revenue service, 

thereby propagating cracks throughout the structure. The stress distribution and crack growth 

results obtained have been compared to a finite element stress analysis of the car and the 

associated fatigue crack growth predictions obtained from the combination of computer models. 
16 
17 

3. Initial Conditions 

This section of the report includes detailed descriptions of the various stages of setup for the fullscale test. Section 3.1 contains information regarding the initial inspection of the test car, as well 

as some minor modifications that were made to prepare it for the test. Section 3.2 discusses the 

characterization of the test system (the machine, with the test car mounted on it). Section 3.3 

details the preliminary DTA analysis of the test car, which helped guide subsequent decisions 

concerning strain measurement locations (documented in Section 3.4) and overall test 

expectations. Section 3.5 describes the preflawing of the tank car, and Section 3.6 explains the 

spectral inputs to the car. 

3.1 Physical Setup 

3.1.1 Jacket Removal 

Shortly after the test car arrived onsite in August 1996, TTCI removed large portions of the 

nonstructural insulation jacket in the areas surrounding the stub sills. This was done to expose 

the stub sill welds and facilitate their visual inspection. Figure 4 shows a photograph of the test 

car upon its arrival onsite. 

Figure 4. Test Car NATX 22746 Upon Arrival at TTC 

After portions of the jacket were removed from the car, the stub sill and bolster web welds were 

lightly sand blasted for the removal of rust and scale buildup. This was done, despite the risk of 

effectively shot peening the surface, because the corrosion near the welds of interest was as 

much as 1/8-inch thick in some areas, rendering visual inspection ineffective. 
18 

3.1.2 Initial Inspection 

Personnel from TTCI, American Railcar Industries (ARI), and GE performed initial visual and 

fluorescent dye penetrant inspections. In general, these inspections revealed the following 

attributes: 

• Poor fitups (gaps) between many welded parts 

• Much undercutting and porosity in all welds 

• Many lug and center-filler weld cracks in both draft pockets 

• Several bolster web weld cracks at both ends 

• Evidence of torch cutting without grinding on bolster webs 

On a macroscopic scale, it was observed that the B-end welds appeared to possess a higher 

quality of workmanship than those of the A-end. In addition, it was apparent that the center 

plate, draft gear, and yoke at the B-end had been replaced at some point while the A-end retained 

all of the original components. The original trucks were also still with the car. The car was in 

better condition than was expected, given its age. Some contributing factors for this may have 

been: 

• 51-pound/foot stub sills (relatively heavy) 

• 3/16-inch thick exterior coils with oversize welds 

• Considerable amount of time spent in storage 

• Light weight is approximately 5-7 kips heavier than cars today 

This initial inspection did not, however, reveal any cracks in the critical regions highlighted by 

the SS-II database. For this reason, and because cracks in the draft pocket would not be 

accessible once the car was on the Simuloader, the car was deemed free of critical region cracks; 

preparations for precracking the test car began (see Section 3.3). As a precaution, many of the 

weld cracks inside the draft pockets were repaired to avoid premature test abortion due to draft 

lug failure. Figure 5 shows a schematic of three of the SS-II critical regions of interest. 
19 

Figure 5. SS-II Critical Regions (SS-II Codes Indicated) 

3.1.3 Test Car Mounting on the Simuloader 

An instrumented load block system (solid draft gear) was installed into the sills of the test car to 

be used as a measurement and control transducer for the longitudinal coupler loads. The car’s Bend interfaced with the LCF actuator at the east end of the machine, and the A-end interfaced 

with the reaction mass at the west end, through spherical bearing arrangements, which allowed 

the car lateral and vertical degrees of freedom. Figures 6 and 7 are pictures of the test vehicle 

mounted on the machine and the solid block LCF arrangement at the B-end of the car. 

Figure 6. Test Car NATX 22746 on Simuloader 
20 

Figure 7. B-End of Test Car, LCF Connection 

Each VCF actuator (in series with a standard load cell) was attached to a 2-inch thick ASTM 

A36 steel plate welded beneath the center sill at each end of the car, slightly inboard of the 

respective coupler carriers. As demonstrated in the schematic of Figure 8, this put the centerline 

of the applied vertical coupler load 10 inches inboard of the outer face of the striker plate (about 

8 inches outboard of the front draft lug face). This effectively placed it halfway between the tank 

head seal weld and the coupler pulling face for the fully extended draft position. Figure 9 is a 

photograph of the B-end VCF actuator. This was done to reduce cost (to apply VCF at the 

coupler pulling face would have required much additional fixturing). 
21 

Figure 8. Schematic of VCF Attachment to Stub Sill 

Figure 9. B-End of Test Car, VCF Connection 
22 

This placement reduced the applied VCF moment to the seal weld by as much as a factor of two 

from the extreme possibility (full coupler extension during an OTR VCF event); the applied VCF 

shear in the simulation was the same as during the OTR test. Though this placement 

proportionally reduced stress magnitudes throughout the vehicle, it did not affect their stress 

concentration locations resulting from applied VCF. This VCF actuator placement was reflected 

in the preliminary FEA of the test car. The primary motivation for this placement of the VCF 

actuator had to do with space constraints, as the actuators were too long to fit underneath the 

LCF spherical bearing arrangement with moment arm extension fixtures. This loss of moment 

arm from the OTR situation was determined to be acceptable for the validation test for reasons 

discussed in Section 3.6.1. 

Another irregularity in this Simuloader VCF setup involved actuator capacities. The VCF 

actuators used with this machine have a maximum force capacity of 55 kips under normal 

conditions. In anticipation of the possible need to amplify loads during the test (in the absence of 

crack growth), a spare 110-kip actuator was used at the B-end of the car. Because only one of 

these was available, the A-end of the car was fixtured with the standard 55-kip jack. The 

decision to use the larger actuator at the B-end was based on the initial observations of B- versus 

A-end weld quality. Because the B-end appeared to possess better workmanship, load 

amplification to drive crack growth was anticipated to be more likely at that end. Table 3 lists a 

few of the basic characteristics. 

Table 3. Basic Simuloader Actuator Characteristics 

Actuator Stroke Capacity Load Capacity Flow Capacity 

LCF (at B-End of Car) 12 inches, 

Static and Dynamic 

 500 kips Tension, 

750 kips Compression 

400 gallons/minute, 

3-Stage Servovalve 

B-End VCF 6 inches, 

Static and Dynamic 110 kips, Double Ended 180 gallons/minute, 

3-Stage Servovalve 

A-End VCF 10.4 inches Static, 

10 inches Dynamic 55 kips, Double Ended 90 gallons/minute, 

3-Stage Servovalve 

The Simuloader bolster modules (vertical, lateral, and yaw bolster actuators) were not used for 

dynamic load application during the test; rather, they were used to raise and align the test car for 

the application of both LCF and VCF. Section 3.6.1 further discusses this, along with VCF jack 

capacities. 

3.1.4 Water Lading 

After the mounting procedures were complete, the car was filled to capacity with water. The 

underlying assumption was that lading had little or no effect on crack growth in the areas of 

interest (the stub sills) and that loading the tank with water served merely to increase the reaction 

mass. In other words, the use of a loaded tank for the loaded and unloaded applied force regimes 

was determined to be acceptable for test simplification. 
23 

3.2 System Characterization 

The Simuloader actuators were controlled with proportional derivative feedback loops based on 

force and displacement signals. The outer loop of this test system, however, was open. That is, 

no automated feedback mechanism exists for the real-time adjustment of drive signals based on 

the machine’s response to system cross talk. For multiaxial test beds, remote parameter control 

systems are typically used to meet this need. To date, it has been TTCI’s experience that these 

do not converge at the lower frequencies at which railcars are typically tested. Due to this outer 

loop, some transient responses were expected and observed during testing. As with a few other 

simplifications, this did not adversely affect the goals of this program for the reasons discussed 

in Section 3.6.1. 

After all of the actuators were calibrated and tuned and the test car was mounted on the machine, 

constant-force frequency sweeps of the system were performed to determine optimum actuator 

response (and any system resonant frequencies). Through calculated response/command transfer 

functions, it was determined that LFC and VCF response deteriorates at frequencies above 2 and 

5 hertz, respectively. One explanation for the relatively poor response of the longitudinal 

actuator (in addition to the sheer volume of hydraulic oil it requires) may be the inertial nature of 

the mass being pushed against (the mechanical slop in the system). Small longitudinal gaps 

existed between contact points throughout the Simuloader/test car system, creating a series of 

tiny impacts and nonlinearities every time the actuator changed direction and crossed through the 

null position. These nonlinearities, when combined with any excited system resonances, could 

increase longitudinal force control difficulty at higher frequencies. The empirical system 

transfer function for the west vertical coupler actuator (acting independently) is plotted in Figure 

10. 

Figure 10. VCF System Transfer Function 
24 

3.3 Preliminary Analysis 

3.3.1 DTA Predictions 

Before the orphan test car was mounted on the Simuloader and instrumented, a preliminary DTA 

was performed with the loads that would be applied in the test (same LCF and VCF loads, and 

application points). ARI completed the FEA of the test car, and SwRI made some preliminary 

crack growth predictions. The details concerning these predictions include proprietary 

information and will not be discussed here. They are, however, discussed to a limited extent by 

Cardinal et al. (1998) and further by Williams (1997). Through these analyses, fatigue critical 

locations were identified. Stress-to-input force ratios were defined for these locations, and some 

estimates of crack life to fracture were calculated (based on these stress-to-force ratios and the 

tank car load spectrum). This information was critical to the test setup. With the aid of these 

analytical models and the inspection database mentioned earlier, the preflaw locations and strain 

gage layout for the full-scale test were determined. A rough estimate of test duration was also 

established at 300,000 equivalent simulated railroad spectrum miles. 

3.3.2 Critical Region Selection 

Because no cracks of consequence were evident from the initial inspections of the orphan car, it 

was necessary to preflaw the car for the fatigue crack growth test. The critical regions chosen as 

the primary focus for this preflawing and subsequent instrumentation were selected based upon 

the following four criteria: 

• Location identified in SS-II database 

• Location identified as a FEA hot spot 

• Location accessible while car is on Simuloader 

• Preflaws spaced to minimize interaction effects 

In general, the FEA of the orphan tank car predicted hot spots (areas with high stress 

concentrations) at the same locations identified by the SS-II database. Critical locations in the 

areas of the sill top flange and tank head seal weld were chosen for testing so crack growth could 

be monitored while the car was mounted on the machine. To minimize any interaction of cracks 

(through load redistributions and resulting local stress changes), it was decided to position only 

one preflaw at each corner of the test car. This preliminary DTA analysis, along with the 

resulting selection of preflaw locations, guided the strain gage location decisions. Figure 11 is 

an isometric view of the sill, with structural and weld labels for reference in subsequent portions 

of this report. 
25 

3.4 Test Car Flaw Induction 

Variation (in weld geometries and the resulting local stress spectrums) and repeatability (in crack 

growth characteristics between two similar regions) were desirable for this full-scale DTA 

validation. In an attempt to simultaneously accomplish both with only four flaws (at the time, 

only four to eight resulting cracks were expected), three of the preflaws were characteristically 

different, while the fourth was a repeat case. Both the B-end left and the A-end right corners of 

the test car were preflawed in the same relative location. Table 4 lists the four preflaws and their 

respective characteristics. Preflaw locations are included in the instrumentation schematics of 

the next section. 

Table 4. Induced Flaw (Preflaw) Locations 

Test Car Corner Weld Area Flaw Type Flaw Acronym 

B-End Left Flange Weld Bottom Toe (in Sill Web) Surface SW@FW-B 

B-End Right Sill Top Flange (Near Seal Weld 

Corner) Corner STF@SW 

A-End Left Seal Weld Top Toe (in Tank Head) Surface TH@SW 

A-End Right Flange Weld Bottom Toe (in Sill Web) Surface SW@FW-A 

The region underneath and surrounding each flaw was polished to a mirror finish before the tank 

car was preflawed to aid in the subsequent crack growth measurements. The 3 surface flaws 

(0.625-inch long) and 1 corner flaw (0.125-inch long) were created with a rotary grinder and a 

jeweler’s saw, respectively. The nominal depth and width measurements for all 4 flaws were 

0.125 inch and 0.010 inch, respectively. These dimensions were based on target aspect ratios for 

the flaws, as well as the limitations of the preflawing technique used. The goal here was to insert 

a stress riser in each of the four critical regions that were to be tested, which would in turn be 

Figure 11. Basic Critical Region Structural and Weld Details 
26 

cycled in the hope of initiating at least one crack. At a microscopic level, the saw and the 

grinder leave rectangular notches, the width of the blade, in the metal. Any resulting cracks are 

expected to grow from one corner of these notches. Figure 12 is a photograph of the B-end right 

corner of the car, complete with the corner flaw and the tank head strain rosette. 

Figure 12. B-End Right Corner Flaw and Tank Head Rosette 

3.5 Transducer Setup 

3.5.1 Data Collection Channel Count 

An array of 36 strain gages was applied to the car as a monitor of absolute stress field and 

gradient values, as well as any changes in carbody compliance due to crack propagation. Two 

string potentiometers were mounted vertically, inboard of the VCF actuators, to be used in 

conjunction with the actuator displacement measurements to monitor the relative vertical 

deflections of each stub sill. In addition to these strain and displacement measurements, the 

applied forces at each actuator were recorded (the feedback signals from the control transducers). 

Table 5 lists all channels. 

The string potentiometers were 25.25 inches inboard of the VCF actuators at both ends of the 

car, which put them about 35.25 inches inboard of the striker face. Figure 8, Section 3.1.3, 

illustrates this arrangement. 

All signals were set up to be externally low-pass filtered at 15 hertz and sampled at a rate of 200 

points per second with a 16-bit digitizer. Because the measurements of interest were acquired in 

a quasi-static manner, the filter cutoff frequencies and rates at which they were sampled are of 

little consequence. They are recorded here for documentation purposes. 
27 

Table 5. Data Collection Channel List 

Channel Name Units Description 

0 LCF kilopounds Longitudinal Coupler Force (B-End) 

1 VCFE kilopounds East Vertical Coupler Force (B-End) 

2 VCFW kilopounds West Vertical Coupler Force (A-End) 

3 VCDE inches East Vertical Actuator Displacement (B-End) 

4 VCDW inches West Vertical Actuator Displacement (A-End) 

5 BLH1 microstrain B-End Left Head Strain #1 (Vertical Rosette Leg) 

6 BLH2 microstrain B-End Left Head Strain #2 (Diagonal Rosette Leg) 

7 BLH3 microstrain B-End Left Head Strain #3 (Longitudinal Rosette Leg) 

8 BLH4 microstrain B-End Left Head Strain #4 (Vertical Uniaxial Leg) 

9 BLW1 microstrain B-End Left Web Strain #1 (Top Inboard Leg) 

10 BLW2 microstrain B-End Left Web Strain #2 (Top Outboard Leg) 

11 BLW3 microstrain B-End Left Web Strain #3 (Bottom Inboard Leg) 

12 BLW4 microstrain B-End Left Web Strain #4 (Bottom Outboard Leg) 

13 BRH1 microstrain B-End Right Head Strain #1 (Longitudinal Rosette Leg) 

14 BRH2 microstrain B-End Right Head Strain #2 (Diagonal Rosette Leg) 

15 BRH3 microstrain B-End Right Head Strain #3 (Vertical Rosette Leg) 

16 BRH4 microstrain B-End Right Head Strain #4 (Vertical Uniaxial Leg) 

17 BRF1 microstrain B-End Right Flange Strain #1 (Inner Leg) 

18 BRF2 microstrain B-End Right Flange Strain #2 (Inboard Edge Leg) 

19 BRF3 microstrain B-End Right Flange Strain #3 (Middle Edge Leg) 

20 BRF4 microstrain B-End Right Flange Strain #4 (Outboard Edge Leg) 

21 ALH1 microstrain A-End Left Head Strain #1 (Longitudinal Rosette Leg) 

22 ALH2 microstrain A-End Left Head Strain #2 (Diagonal Rosette Leg) 

23 ALH3 microstrain A-End Left Head Strain #3 (Vertical Rosette Leg) 

24 ALH4 microstrain A-End Left Head Strain #4 (Vertical Uniaxial Leg) 

25 ALW1 microstrain A-End Left Web Strain #1 (Longitudinal Rosette Leg) 

26 ALW2 microstrain A-End Left Web Strain #2 (Diagonal Rosette Leg) 

27 ALW3 microstrain A-End Left Web Strain #3 (Vertical Rosette Leg) 

28 ALW4 microstrain A-End Left Web Strain #4 (Vertical Uniaxial Leg) 

29 ARF1 microstrain A-End Right Flange Strain #1 (Inner Leg) 

30 ARF2 microstrain A-End Right Flange Strain #2 (Inboard Edge Leg) 

31 ARF3 microstrain A-End Right Flange Strain #3 (Middle Edge Leg) 

32 ARF4 microstrain A-End Right Flange Strain #4 (Outboard Edge Leg) 

33 BLBT microstrain B-End Left Top Flange Bending Strain 

34 BLBB microstrain B-End Left Bottom Flange Bending Strain 

35 BRBT microstrain B-End Right Top Flange Bending Strain 

36 BRBB microstrain B-End Right Bottom Flange Bending Strain 

37 ALBT microstrain A-End Left Top Flange Bending Strain 

38 ALBB microstrain A-End Left Bottom Flange Bending Strain 

39 ARBT microstrain A-End Right Top Flange Bending Strain 

40 ARBB microstrain A-End Right Bottom Flange Bending Strain 

41 SPE inches East Vertical Sill Displacement (B-End) 

42 SPW inches West Vertical Sill Displacement (A-End) 

43 LCF_D kilopounds Longitudinal Coupler Force Drive Signal 

44 VCFE_D kilopounds East Vertical Coupler Force Drive Signal 

45 VCFW_D kilopounds West Vertical Coupler Force Drive Signal 
28 

3.5.2 Carbody Response Strains 

The strain gages were located along the stub sills and in the vicinity of the induced flaws. There 

were 24 uniaxial gages and 4 rectangular rosettes (all with 0.125-inch grids); each gage was 

individually wired in a quarter-bridge configuration. Eight of the gages were mounted along the 

sill of the car to measure remote sill bending and macro carbody sensitivity to crack growth. The 

rest of the gages were used near the induced flaws for FEA correlation and measurement of local 

sensitivity to crack growth measurement. The monitoring of stress fields inside the tank was 

considered before the test began in order to get a sense of the bending gradient through the 

thickness of the shell. This was abandoned primarily due to the complexity (and resulting cost) 

of strain gage installation inside the tank and the necessary protection of their leads from the 

water. Table 6 is a summary of the strain gage layout. 

Table 6. Validation Test Strain Gage Summary 

Test Car Corner Applied Strain Gages Mounting Surface 

B-End Left 1 Rosette, 1 Uniaxial Tank Head 

B-End Left 4 Uniaxial Sill Web 

B-End Right 1 Rosette, 1 Uniaxial Tank Head 

B-End Right 4 Uniaxial Sill Top Flange 

A-End Left 1 Rosette, 1 Uniaxial Tank Head 

A-End Left 1 Rosette, 1 Uniaxial Sill Web 

A-End Right 4 Uniaxial Sill Top Flange 

All Four (Bending) 2 Uniaxial Sill Top and Bottom Flange 

Figures 13 through 17 contain the strain gage layout information for the orphan test car. As can 

be seen in Table 5, the first two letters of each channel designation indicate the corner of the 

vehicle on which each particular gage is located. The third letter indicates whether the gage is 

mounted on the tank head (H), sill web (W), or sill top flange (F). Finally, the number (the last 

digit) is used to differentiate other nearby gages. This last number is the only portion of the 

channel acronym that is indicated next to each gage in the schematic of each test car corner. The 

channel designation system differs slightly for the bending gages in the last two letters; the third 

letter stands for bending (B), and the last letter indicates whether the gage is on the top (T) or 

bottom (B) flange. In addition to the strain gage locations in the figures, the preflaw locations 

are called out. 
29 

Figure 13. B-End Left Strain Gages and Preflaw 
30 

Figure 14. B-End Right Strain Gages and Preflaw 
31 

Figure 15. A-End Left Strain Gages 
32 

Figure 16. A-End Right Strain Gages and Preflaw 

Figure 17. Sill Bending Strain Gages (at Both Ends of Car) 
33 

3.6 Simulation Inputs 

3.6.1 DTA Validation; Not OTR Simulation 

For the purposes of this validation test, the precise loading of the vehicle with values from the 

OTR target spectra was not important, as the response of the actuators was collected as input for 

the DTA model. This represents a departure from typical simulations where OTR spectral 

reproduction is of utmost importance. 

In the case of transient response (see Section 3.2), if the B-end VCF actuator overshot the target 

load of 35 kips by 5 percent on average (to 36.75 kips), the overshoot was reflected in the input 

for the DTA model of this car. The same was true for clipping (see Section 3.3.2). Because the 

collected machine inputs to the car were used in the crack growth analyses performed for the 

validation, transient responses and clipping were initially determined to be acceptable for this 

test and warranted no further attempts at correction. 

As mentioned in Section 3.1.3, the VCF actuator was mounted underneath the sill, effectively 

cutting the applied moment to the seal weld in half. This was a cost-saving measure and was 

accounted for in the preliminary DTA of the test car. In other words, the VCF was applied in the 

FEA at the same position as it was in the test. 

LCF and VCF spectra were applied to the test car in series without corresponding bolster 

motions. Thus, the relative phasing between various OTR carbody inputs and corresponding 

summation effects on the stress spectra of critical regions was lost. This series application 

reduced the number of variables necessary for the DTA model validation and was reflected in the 

crack growth analyses performed. 

Finally, as the next section will discuss, the inputs to the test car were truncated to reduce test 

time. This was also reflected in the crack growth analyses performed. 

In short, many test simplifications were used to reduce the program’s cost without compromising 

its objectives. Because of these, 300,000 DTA spectrum miles (the duration of the test) is in no 

way correlated with 300,000 revenue service miles of fatigue damage. Again, this was a DTA 

validation, not an OTR simulation. 

3.6.2 Drive File Development 

SwRI developed a scaled load schedule from the most recent release of the tabulated rainflow 

cycle-counted data published in the AAR-MSRP (the first phase of Task Order 108) that 

represents a 10,000-mile block of longitudinal and vertical coupler loading for 100-ton tank cars. 

The tank car industry currently uses this load schedule for the DTA program; Appendix A lists 

the portion of it used to develop inputs for the full-scale validation test. Cardinal et al. (1998) 

further describes the methodology behind the distillation of this load schedule from the AARMSRP data. 
34 

For Simuloader input development, six components of this DTA load schedule were extracted to 

create what is hereafter referred to as the validation load schedule: 

• Loaded tank VCF events, positive = upward (LVPU) 

• Unloaded tank VCF events, positive = upward (UVPU) 

• Loaded tank LCF buff events, negative = buff (LLBUF) 

• Unloaded tank LCF buff events, negative = buff (ULBUF) 

• Loaded tank LCF draft events, positive = draft (LLDFT) 

• Unloaded tank LCF draft events, positive = draft (ULDFT) 

Because these components were extracted from rainflow cycle-counted data, the number and 

magnitude of the events were known, but their frequency content and relative sequencing were 

not. For the creation of drive files for this test, two basic assumptions were utilized. First, metal 

fatigue (in a single degree of freedom system) is generally independent of the frequency of the 

applied stresses. Second, if the ratio of accumulated mileage per spectrum pass to total 

simulated mileage (in this case, 10,000/300,000 miles) is small, then the load sequence is 

effectively random as far as fatigue crack growth mechanisms are concerned (both large and 

small magnitude cycles are evenly distributed throughout the test). 

The FEA of the test car was used to determine the most sensitive critical region weld for each 

loading regime (LCF buff, LCF draft, VCF downward, VCF upward) and the corresponding 

stress/force ratios. Again, Williams (1997) and Cardinal et al. (1998) further discuss these 

issues. These stress/force ratios were used to truncate the input spectra at the aforementioned 

threshold level of 5.1 ksi. This truncation level resulted in a 97.3 percent reduction in the total 

number of cycles needed for fatigue crack propagation. Next, the remaining cycle counts for 

each component of the validation load schedule were rounded off to the nearest whole number 

because partial cycles cannot be applied in the laboratory as they can in the numerical model. 

Sinusoidal drive signals for each actuator were created in an ordered random fashion from the 

remaining cycles of each of the six loading regimes. In other words, the positive peaks of the 

loads were ordered (descending from the highest LCF draft and VCF upward loads) while the 

alternating components were applied randomly (within this positive peak superstructure) at 

constant frequencies of 2 and 5 hertz times the frequencies determined in the initial system 

characterization. The loads within a spectrum pass were applied in this fashion because a 

complete random structuring would introduce unnecessary additional fatigue-causing cycles that 

were not in the original tabulated data. The segment of the vertical coupler drive signal in Figure 

18 demonstrates this resultant stair stepping of values, with ranges sharing peak values occurring 

together in series. 
35 

Figure 18. Segment of VCF Input Sinusoid 

In summary, six individual drive files were created: two for the VCF actuators and four for the 

LCF actuator. These 6 files, combined in a sequence, simulated 10,000 miles of fatigue damage 

and constituted a test cycle (with 30 test cycles completing the 300,000-mile test). With the aid 

of truncation, the test was accelerated to a rate of approximately 7,936 spectrum miles per hour 

of actual run time. This estimate, however, does not include inspection time, pauses between 

drive files, or any of the other various sources of machine downtime. Table 7 lists the six drive 

files, along with some characteristics. 

Table 7. 10,000-Mile Validation Load Schedule Breakdown 

Drive File Command Original DTA Truncated Cycle Sinusoid (Load Maximum– Cycle Count Count Duration Case) Up/Draft 

LVPU 394,996.0 9,161 35.8 minutes 61.25 kips 

UVPU 159,738.0 6,189 22.6 minutes 33.75 kips 

LLBUF 7,558.6 197 6.3 minutes 

ULBUF 7,963.4 194 4.5 minutes 

LLDFT 22,801.4 227 4.8 minutes 410 kips 

ULDFT 15,747.2 109 1.8 minutes 300 kips 

Command 

Minimum– 

Down/Buff 

- 51.25 kips 

- 41.25 kips 

- 830 kips 

- 650 kips 
36 
37 

4. Test Operations 

The third phase of Task Order 108 (Full-Scale Damage Tolerance Test) was further subdivided 

into three major portions. First, the car was precracked with the application of constant 

amplitude cyclic loading. When four surface cracks were apparent in the critical regions of 

interest, the spectrum loading of the car was initiated. After the accumulation of 200,000 

spectrum miles, the test was paused, and the VCF loads were amplified to increase crack growth. 

At 300,000 spectrum miles, the car underwent a final visual inspection, was removed from the 

machine, and was sectioned for a fractographic analysis. 

This section describes the procedures that were used during the program. Section 4.1 contains 

information regarding the crack initiation procedures that were used to precrack the test vehicle. 

Section 4.2 presents the fatigue crack growth and carbody compliance measurements as the test 

progressed. Section 4.3 discusses the adjustments to testing procedures that were made twothirds of the way through the full-scale test. Finally, Section 6.4 covers the post-test inspections, 

fractography, and analysis that occurred after the spectrum loading was complete. Table 8 

provides an overview of the sequence of significant testing events. 

Table 8. Sequence of Significant Full-Scale Test Events 

Accumulated Fatigue Damage Tasks Completed; Events of Interest 

300,000 Miles of Revenue Service Estimated, Initial Car Inspection, Instrumentation, System 

Several Years in Storage Characterization, and Preflawing 

156,500 LCF and VCF Constant Amplitude Cycles Test Car Precracking Completed 

70,000 DTA Test Spectrum Miles Inspection Technique Change—No VCF 

Preload, Dye Penetrant to Aid Measurement 

200,000 DTA Test Spectrum Miles VCF Loads Doubled to Increase Crack 

Growth Rates 

300,000 DTA Test Spectrum Miles End of Test, Fiber Optic Scope Inspection with 

VCF Preload, Sill Sectioning, and Fractography 

4.1 Crack Initiation 

As discussed, the car was polished and preflawed at each of the four corners. These induced 

flaws were subsequently precracked with the application of constant amplitude cyclic load 

blocks with maximum levels not exceeding approximately 80 percent of the peak spectrum load. 

Precracking was performed under tensile-only, as well as fully-reversed, loading (perpendicular 

to the crack surfaces), using both the longitudinal and vertical coupler actuators of the 

Simuloader. Approximately 156,500 load cycles were necessary to create fatigue cracks with a 

surface length of at least 0.15 inches from any of the flaws. The precracking process was 

terminated when what was eventually designated as seven cracks had initiated on the structure 

(the goal was four). Discussed further in Section 5.1, these initial cracks were lettered A, B, C, 

D, E, F, and G. Table 9 lists the breakdown of the precracking cycles that were applied. 
38 

Table 9. Precracking Loads Applied in Full-Scale Test 

Load Case Direction Endpoints Cycle Count 

VCF Downward 4 to 40 kips 5,000 

LCF Buff 75 to 445 kips 5,000 

VCF Downward 4 to 40 kips 3,500 

LCF Buff 75 to 505 kips 5,000 

VCF Downward 4 to 40 kips 10,000 

LCF Buff 55 to 550 kips 10,000 

VCF Fully Reversed 40 kips 5,000 

VCF Fully Reversed 40 kips 15,000 

VCF Fully Reversed 40 kips 30,000 

VCF Fully Reversed 37 kips 15,000 

VCF Upward and Downward 42 kips and 48 kips 15,000 

VCF Upward and Downward 42 kips and 48 kips 10,000 

VCF Upward and Downward 41 kips and 48 kips 22,500 

LCF Fully Reversed 425 kips 5,000 

LCF Buff and Draft 630 kips and 400 kips 500 

The logic behind this precracking load schedule was based on SwRI experience. SwRI engineers 

were present to give real-time guidance based on laboratory results during this part of the 

program. At 1.30 inches after precracking, crack E (in the tank head at the A-end left) was the 

primary motivator to start spectrum loading the test vehicle. 

4.2 Spectrum Loading 

4.2.1 Spectrum Crack Growth 

The variable amplitude spectrum loading portion of the test was broken into 10,000-mile 

increments, corresponding to the length of the input validation load schedule. Within the 

schedule, the loaded and unloaded VCF and LCF cycles were applied sequentially to the stub 

sill. One pass through the validation load schedule began with the VCF cycles applied to each 

end of the car (applied simultaneously to both ends, in parallel), followed in series by LCF cycles 

applied at the B-end and reacted at the A-end. The Simuloader bolster modules (vertical, lateral, 

and yaw actuators) were not used for dynamic load application during the test; they were only 

used to position the test car for the application of the LCF and VCF loads. 

The test was paused for crack inspections between validation load schedule passes (at 10,000-

mile intervals). At that time, existing crack lengths were measured with the aid of clear plastic 

flexible scales and magnifying glasses. For the precracking, the first 7 test inspections (the first 

70,000 spectrum miles of the test), and the post-test fiber optic scope inspection, these 

inspections were done with the Simuloader energized, and a static vertical load of 50 kips was 
39 

applied to the stub sills in a downward direction. This loading was done to open up the crack 

tips and make them more easily visible against the polished metal background. 

The entire car was visually inspected for new cracks at 20,000-mile intervals (every other 

validation load schedule pass). At these intervals, constant amplitude marker bands were applied 

to the car with the VCF actuators. As with the coupons before the full-scale test (see Section 

1.3.2), these marker bands were applied at a maximum of 90 percent of the peak downward 

spectrum load, with a load ratio of 0.8 (at 5 hertz). This translated to cyclic loading with a 41.5-

kip mean and a 4.5-kip amplitude (fully reversed around that mean preload) at both ends of the 

car. For the first band, the number of such cycles applied was 40,000. The marker band cycle 

count was then decreased by 2,500 cycles every 20,000 spectrum miles to account for increased 

crack growth rates as the test progressed, thereby keeping all marker bands approximately the 

same width. Because it was not known whether this marker banding effort was successful during 

the test, the cycle count reduction was frozen to 17,500 cycles at 200,000 spectrum miles. Table 

10 contains the details pertaining to the loads that were applied to the car. 

Table 10. Marker Bands Applied in Full-Scale Test 

VCF Marker Band Cycle Count (Length) Spectrum Miles Accumulated 

1 40,000 20,000 

2 37,500 40,000 

3 35,000 60,000 

4 32,500 80,000 

5 30,000 100,000 

6 27,500 120,000 

7 25,000 140,000 

8 22,500 160,000 

9 20,000 180,000 

10 17,500 200,000 

11 17,500 220,000 

12 17,500 240,000 

13 17,500 260,000 

14 17,500 280,000 

15 17,500 300,000 

4.2.2 Carbody Compliance 

Before the precracking process and subsequently at 50,000-mile test intervals, quasi-static 

sensitivity tests were performed to quantify changes in the vehicle’s compliance (linear stiffness) 

as the test progressed. Longitudinal loading was applied to the car in static increments of 100 

kips, spanning the range of 0 to 500 kips, for a duration of a few seconds at each step. This was 

done in buff and draft. Vertical loading was also applied in 10-kip increments from 0 to 50 kips 

in the same fashion (both upward and downward). As these incremental loads were applied, a 

strain survey was continuously recorded on all channels. In addition to FEA critical region 
40 

stress-to-force ratio verification, these periodic tests provided information concerning load path 

and stiffness changes in the presence of propagating cracks. 

Strain circuit integrity was also checked on all bridges at 50,000-mile intervals. This was done 

with two processes. First, a strain indicator was used at the gage (removing all data acquisition 

cabling and conditioning from the signal) to check for any offsets due to material yielding or 

gage peeling. Second, all signals were balanced, and a resistance calibration was performed to 

ensure that the gain of any individual signal conditioner had not changed. 

4.2.3 System Control and Response 

Finally, system response was monitored throughout the full-scale test. The feedback from the 

actuators was recorded periodically for the validation load schedule (every 50,000 spectrum 

miles) and the marker band drive files (every other band). Due to reasons already discussed, 

actuator transient response was expected, which would add many low amplitude cycles to the 

full-scale test. The extent of this was quantified with rainflow cycle counting, and the resulting 

files were used for the actual DTA parameter adjustments and validation. In other words, the 

exact loads that were input into the test car were put into the model. This was done to eliminate 

any validation error associated with Simuloader/vehicle system response errors during the 

application of the loads. 

4.3 Mid-Test Procedure Adjustments 

4.3.1 Inspection Technique 

The crack inspection at 70,000 spectrum miles was the last to be done with a vertical load on the 

sills of the car. Safety considerations concerning the cutting power of the pilot pressure hoses (in 

the event of a break) ended this practice, as the crack inspections put the inspector within a few 

feet of several of these hoses. From that point on (all inspections after and including the one 

performed at 80,000 spectrum miles), dye penetrant was routinely used to assist in locating the 

crack tips. With the sills vertically loaded (as with the past inspections), red dye was sprayed 

onto all known cracks. After that, the machine was shut down, developer was applied, and crack 

lengths were measured with the aid of clear plastic flexible scales and magnifying glasses. The 

car was only loaded for the application of the dye to open the crack tips for better penetration. 

For the final inspection with a fiber optic scope (at 300,000 spectrum miles), however, the car 

was repositioned so that the entire Simuloader would not need to be energized; the pressurized 

pilot hoses were shielded (from the scope operator); and the sills were again loaded. 

4.3.2 Input Load Spectrum 

After the accumulation of 200,000 spectrum miles, the test was stopped for further data analysis. 

At that point, the critical region cracks had not grown appreciably; reasons for this were under 

investigation. The end result of this analysis was the amplification of the VCF portion of the 

validation load schedule for the remainder of the test. The following paragraphs discuss the 

motivations for this. Due to the length of the hiatus, carbody compliance and existing crack 

lengths were measured twice before testing resumed, once before and once after the pause in 

testing. 
41 

At 200,000 spectrum miles, an indepth comparison was made between the test vehicle FEA and 

the stresses recorded during the compliance tests. A comparison matrix was formed between the 

measured strains (scaled to stress with E = 29,000 ksi), the calculated von Mises stress 

summations (for the rosettes), and the FEA stresses at longitudinal loads of 500 kips (buff and 

draft) and vertical loads of 50 kips (upward and downward). After outliers were discarded, 

nominal weighted averages were calculated from a matrix that contained 40 empirical 

measurements (36 strains and 4 displacements) from 6 different compliance strain surveys (taken 

at different points throughout the test). When combined with the analytical FEA results, this 

yielded a 40 by 7 array of values to compress for each of the 4 load cases. As previously stated, 

the details of this comparison are proprietary and are discussed by Williams (1997) and Cardinal 

et al. (1998). Through the nominal weighted averages, the initial FEA of the test car was 

determined to be conservative by a factor ranging from one to three, depending on the critical 

region and load case of interest. In other words, the FEA predicted stresses that were anywhere 

from accurate to three times higher than what was observed in the laboratory. These nominal 

weighted-average factors, however, are based on a linear FEA of the uncracked structure, and 

they do not distinguish changes in carbody compliance as cracks progressed throughout the test. 

This issue warrants further study. Table 11 shows an example of the comparison matrix that was 

constructed for the seal weld critical regions. 

Table 11. Empirical/Analytical Comparison Matrix Example 

First Strain Average of 

Survey 

(Before 

Next Five 

Strain 

FEA 

Prediction 

FEA/Test 

#1 Ratio 

FEA/Tests 

#2-6 Ratio 

Nominal FEA/Test 

Ratio 

Precracking) Surveys 

BLHvM 

BLH1 

BLH4 

BRHvM 

BRH3 [Refer to Williams (1997) and Cardinal et al. (1998)] 

BRH4 

ALHvM 

ALH3 

ALH4 

To ensure sufficient crack growth for DTA model validation during the pending last segment of 

the full-scale test, it was decided that the VCF portion of the validation load schedule would be 

amplified by a factor of 2 and clipped at 55 kips. In other words, the VCF loads were increased 

to 200 percent of their original OTR values, and any cycle of the amplified input that exceeded 

55 kips was attenuated to that same value. This amplification of the VCF portion of the 

validation load schedule was in effect for the remainder of the full-scale test (100,000 spectrum 

miles). 

The logic behind the amplification amounted to a moment arm correction. As discussed 

previously, the vertical coupler actuator was approximately halfway between the seal weld and 

the fully extended coupler pulling face. Though the shear stresses in the critical regions were 

relatively unaffected by this placement, the applied moment was as little as half its extreme 
42 

potential. This was initially determined to be acceptable for DTA model validation and was 

accounted for in the preliminary analysis of the car. When it was discovered that the initial stress 

predictions were conservative by such a large degree, however, this loss of applied moment 

became more important. 

The logic driving the decision to clip the amplified VCF load spectrum was to protect the car 

from unintentional catastrophic sill damage, as well as to allow identical load application to both 

ends of the car. Clipping was justified because the most recent car design guidelines specify that 

a tank car must withstand vertical loads of 50 kips (in both directions) and the A-end actuator 

had a peak capacity of 55 kips (compared to 110 kips at the B-end). Supporting this was the 

brief coupon investigation mentioned earlier that suggested the impact of clipping on crack 

growth behavior may be small in specific variable amplitude situations. At the 55-kip clipping 

level, only 115 cycles (99 LVPU and 116 UVPU) were clipped. This represented less than 1 

percent of the total VCF cycle count. 

After this FEA/test comparison, SwRI computed NASGRO fatigue crack growth predictions 

with the amplified and clipped load schedule and the revised stress/load ratios for the critical 

regions, based on strain data from the test. A low R-ratio (load ratio) model was used to add a 

conservative degree to the predictions (a prediction of slower growth would indicate a need for 

more amplification). With a twofold increase in VCF, incremental crack growth was predicted 

to increase by a factor as large as nine. Because the crack aspect ratios were still assumed at this 

stage of the test and the stress gradients through the thickness of the material were unknown, 

however, the confidence level in these predictions was limited. 

4.4 Post-Test Analysis 

4.4.1 Final Critical Region Inspection 

At 300,000 spectrum miles, sufficient crack growth had been achieved for the validation of the 

DTA model. The test was stopped, and personnel from the General American Transportation 

Corporation and SwRI joined with TTCI in the final car inspection. In addition to the dye 

penetrant inspection typical of the entire test, a fiber optic scope was used to inspect and 

document crack measurements and geometries. The fiber optic scope was used in conjunction 

with a partial machine shutdown and some protective tarps so cracks could be inspected safely 

with a vertical load on the sills of the car. The scope proved to be quite helpful in determining 

the existence of cracks (especially in hard-to-reach locations) but difficult to use for actual 

surface length measurements. 

4.4.2 Sill Sectioning and Fractography 

At the conclusion of the full-scale test, the instrumentation was removed from the test car, and 

the car was removed from the Simuloader for sill sectioning. The car was rolled on its side, and 

each sill was flame-cut out of the tank car with a frame of tank head material about 12 inches 

wide. The regions containing both the seal weld and the flange weld (the inboard portions where 

flaws had been inserted) were then removed from these sections and sent to SwRI for post-test 

fractographic analysis. At SwRI, the pieces were further sectioned, and the fracture surfaces 

were exposed for more accurate crack length and depth measurements. The details of this 
43 

fractographic analysis and the crack growth rate behavior are contained in the companion report 

by Benac, et al. (1998). 

4.4.3 Damage Tolerance Validation 

SwRI completed the actual DTA model validation as part of the overall industry program, which 

Cardinal et al. documents (1998). In that report, a correlation analysis has been performed 

between the empirical data (both Simuloader and fractographic) and analytical data (FEA and 

NASGRO). That report includes recommendations for the SSWG, including model parameter 

adjustments. 
44 
45 

5. Results and Discussion 

This section includes discussions of the various results of the full-scale test that are not addressed 

in any of the companion reports referenced. Section 5.1 contains details concerning the surface 

crack growth measurements that were made throughout the program. Section 5.2 details the 

compliance test results and contains a few notes on the strain measurements. Section 5.3 

describes and quantifies the response of the Simuloader/vehicle system with the aid of rainflow 

cycle counting. Section 5.4 provides brief introductions and references to the companion reports. 

In this report, anything suspected to be a crack has been referred to as a crack. During the final 

inspection (with the fiber optic scope) and the fractographic analysis, a few of these cracks were 

shown to be surface aberrations, not true cracks. This is addressed to some degree here and to a 

larger degree in the companion reports. In addition, the presentation and discussion of all data is 

hereafter in accordance with the following sign conventions: 

• LCF draft: Positive 

• LCF buff: Negative 

• VCF upward: Positive 

• VCF downward: Negative 

• Stress/strain tension: Positive 

• Stress/strain compression: Negative 

• Displacement extension: Positive 

• Displacement retraction: Negative 

5.1 Spectrum Crack Growth 

5.1.1 Initial Precracking Success 

After what was eventually designated as seven cracks initiated in the car’s critical regions, the 

precracking process was terminated. Figures 20, 22, and 26 in Section 5.1.2 show sketches of 

these cracks (lettered A, B, C, D, E, F, and G). Cracks A and B extended from either side of the 

SW@FW surface flaw at the B-end left corner of the car and remained unconfirmed (possible 

scratches, rather than cracks) throughout the test. Like A and B, cracks C and D extended from 

either side of the TH@SW surface flaw at the A-end left corner of the car. Cracks E and F were 

also at the A-end left corner in the top toe of the seal weld. These cracks (E and F) were actually 

the same crack, divided into a lateral and longitudinal portion along the seal weld, respectively. 

All four of the A-end left cracks were difficult to distinguish due to the poor weld quality in that 

area. Finally, at the A-end right corner of the car, crack G extended from the outboard side of 

the SW@FW surface flaw. Interestingly, crack G apparently disappeared or was no longer 

visible on the surface at the 80,000-mile inspection. This also occurred with cracks A and B at 

the same time. The 80,000-mile inspection was the first inspection with dye penetrant and no 

vertical preload, due to safety concerns. 
46 

5.1.2 Spectrum Cracking Success 

Appendix B contains a complete log of all surface crack measurements that were made during 

this full-scale validation test. Where a crack was growing at both tips (and both were 

observable), a reference mark was scribed into the metal, and the crack was given two letter 

designations, one for each tip. This is reflected in the crack figures and in the appendix table. 

Figures 19 through 26 are schematic diagrams of all these cracks at 300,000 spectrum miles (the 

end of the test). 

Figure 19. B-End Seal Weld Cracks 

Figure 20. B-End Left Flange Weld Cracks and Preflaw 
47 

Figure 21. B-End Right Seal Weld Cracks and Preflaw 

Figure 22. A-End Left Seal Weld Cracks and Preflaw 
48 

Figure 23. A-End Left Sill Top Flange Crack 

Figure 24. A-End Right Seal Weld Cracks 
49 

Figure 25. A-End Right Sill Top Flange Cracks 

Figure 26. A-End Right Flange Weld Crack and Preflaw 

Several of the 30 cracks listed in the spectrum crack growth log occurred in weld toes. Their 

existence (or lack thereof) was only proven in the post-test fractographic efforts at SwRI. Their 

approximate measurement uncertainty ranged from ±0.01 to ±0.05 inch, depending upon the 

accessibility of the critical region. 
Three discontinuities occurred in the surface crack length measurements, reflected in the crack 

growth log by heavier dividing lines. The first of these appeared after 70,000 spectrum miles, 

when the inspection technique changed. At that point, the vertical preload was discontinued, and 

dye penetrant was added to the process. This change may have influenced the measurements in 

two conflicting ways: the crack tips were not held open (making the cracks appear shorter), and 

the dye penetrant led the crack tips (making the cracks appear longer). It was not determined 

whether these two effects cancelled each other. The second discontinuity occurred at 200,000 

miles. Because the mid-test hiatus lasted a few months, a second inspection was performed 

before testing resumed. A few of the cracks appeared to look different after the hiatus; a few of 

the previous reference marks were difficult to distinguish and were scribed into the metal again. 

The last discontinuity was at 300,000 miles, when the final inspection was performed twice. The 

second-to-last inspection was done with routine procedures at the conclusion of the test. The 

final inspection, however, was done with the aid of both a fiber optic scope and a vertical preload 

on the sills of the car. The car was positioned, and the operator was shielded to remove safety 

risks from pilot pressure hoses. 

5.1.3 Marker Banding Success Indications 

During the last leg of the test (at about 293,000 spectrum miles), a stud from the A-end VCF 

actuator broke, and the test was paused for machine repair. Upon examination of this stud, it was 

apparent that it had fractured by fatigue (as opposed to a static overload fracture), and the cracks 

had been growing through it during several previous tests. In addition, beach marks (striations) 

from the marker banding in this test were evident even on a macroscopic scale. The stud was 

sent to SwRI for further inspection and confirmation of these conclusions, which is detailed by 

Benac et al. (1998). This was significant, as it was the first indication (before the post-test 

sectioning of the car) that the marker banding techniques used during the full-scale test were 

effective. Figure 27 depicts one of the load stud fracture surfaces. 

Beach 

Marks 

Figure 27. VCF Load Stud Fracture Surface at 6.6x Magnification 

50 
51 

5.2 Carbody Compliance 

5.2.1 Compliance Test Results 

During this program, a total of nine measurements of critical region stiffness were taken with 

static strain surveys at the following intervals (in sequence): 

1. Before precracking cycles were applied to the car 

2. After the precracking process, before spectrum loading 

3. After the application of 50,000 spectrum miles 

4. After the application of 100,000 spectrum miles 

5. After the application of 150,000 spectrum miles 

6. After the application of 200,000 spectrum miles, before the hiatus 

7. After the application of 200,000 spectrum miles, after the hiatus 

8. After the application of 250,000 spectrum miles 

9. After the application of 300,000 spectrum miles, at the end of the test 

Appendix C includes the plotting for the calculated stress data from these nine surveys. For 

comparison purposes, the data was organized into the following nine major channel groups: 

1. Vertical sill deflections: VCDE, VCDW, SPE, SPW 

2. B-end sill bending stresses: BLBT, BLBB, BRBT, BRBB 

3. A-end sill bending stresses: ALBT, ALBB, ARBT, ARBB 

4. Vertical head stresses: BLH1, BLH4, BRH3, BRH4, ALH3, ALH4 

5. Von Mises head stresses: ALHvM, BLHvM, BRHvM 

6. Vertical web stresses: BLW1, BLW2, BLW3, BLW4, ALW3, ALW4 

7. A-end Von Mises web stress: ALWvM 

8. B-end longitudinal flange stresses: BRF1, BRF2, BRF3, BRF4 

9. A-end longitudinal flange stresses: ARF1, ARF2, ARF3, ARF4 

The data from these nine groups of channels was further subdivided into the three different 

compliance load cases (LCF, B-end VCF = VCFE, and A-end VCF = VCFW). In all, Appendix 

C contains 243 plots (9 channel groups, 9 strain surveys for each group, and 3 load cases for each 

survey). 

The tables in Appendix D present compliance data from the 9 strain surveys at force levels of 

500 kips LCF buff, 500 kips LCF draft, 50 kips upward VCF, and 50 kips downward VCF, as 

well as calculated principal (p1 and p2) and von Mises stress data for the four rosettes. The 

principal stress direction results (BLHang, BRHang, ALHang, and ALWang) represent the acute 

angle from the axis of gage 1 (different for each corner) to the nearest principal axis, regardless 

of whether it is the maximum or minimum principal stress axis. When positive, this angle is in 

the direction of gage numbering. When negative, this angle is in the opposite direction. The first 

four tables of Appendix D are dominated by raw strain data. The subsequent four tables are 
52 

comprised mostly of calculated stress and standard deviation data for three groupings 

(compliance test 1, tests 2 through 6, and tests 3 through 9). The stress calculations in these 

tables were performed with Young’s modulus equal to 29,000 ksi and 0.275 for Poisson’s ratio. 

5.2.2 Sill Deflections and Bending Strains 

The sill deflections and bending strains were essentially linear and repeatable for LCF and VCF 

at both ends of the car, with the exception of the A-end during the first buff strain survey (before 

precracking). This initial A-end discrepancy may have been caused by load path changes within 

the structure, strain gage break-in, or a combination of both. The initial sensitivity change 

between the first and second compliance test (before and after precracking) is also apparent in 

some of the other measurements. This change in sensitivity seemed the most pronounced in the 

case of buff, which may be a consequence of the fact that buff was the most variable load case in 

terms of load application geometry (the car and machine may have shifted relative to one another 

between strain surveys). 

An unexpected result occurred in the bending response of the test car to LCF buff. In the initial 

FEA, longitudinal tension in the top flange and compression in the bottom flange was expected. 

However, the reverse of this proved to be the case at both ends of the car. Under a buff load, the 

top flanges (at the location of the strain gages) went into longitudinal compression and the 

bottom into tension. This may have been due to a vertical reaction force (of the gross carbody 

reaction to LCF) applied just inboard of the striker, as demonstrated in Figure 28. 

Figure 28. Schematic of Potential LCF Load Path 

This polarity (compression in the top flanges and tension in the bottom) was also the case for 

upward VCF; the reverse was true for downward loading (tension in the top flanges and 

compression in the bottom). The top and bottom flanges were in tension when draft loads were 

applied to the car. Finally, the sill was forced down at all four vertical displacement 
53 

measurement locations under buff and downward loads; the sill was forced up under draft and 

upward loads. This latter observation was expected in the test car’s FEA. 

Other qualitative observations that were made concerning the sill bending strains and 

displacements include: 

• Vertical displacement magnitudes at the string potentiometers were greater for LCF buff 

than draft, yet approximately the same for upward and downward VCF. 

• Vertical displacement magnitudes at the actuators were greater for upward VCF than 

downward, yet approximately the same for LCF buff and draft. 

• Vertical displacements at the actuators were more linear and repeatable than those 

inboard at the string potentiometers. 

• Downward VCF caused the most vertical displacement at the actuators, but LCF buff 

caused the most at the string potentiometers. 

• Bending strain response magnitudes to LCF draft were greater than to buff, though 

upward and downward VCF were similar. 

• Both ends of the car had about the same compliance strain levels. 

• The highest uniaxial strain magnitudes (on these bending gages) were recorded during 

LCF draft. 

All data from all channels is plotted and tabled in Appendices C and D, respectively. The string 

potentiometers, SPE and SPW, were not used during the first strain survey (they were added 

later). In addition, the completion bridge for strain gage, ARBB, had a loose wire during the 

second survey, which was fixed shortly afterward. The data from these channels during the 

referenced surveys may be disregarded. 

5.2.3 Tank Head Gradients and Summations 

Tank head strains were measured with uniaxial gages and rosettes at three corners of the test car: 

the B-end left, the B-end right, and the A-end left. At each corner, comparisons were made 

between the pair of uniaxial strains perpendicular to the seal weld (e.g., channels BLH1 and 

BLH4) and between the calculated von Mises stresses (from each rosette). Linearity and 

repeatability varied between corners but were better under VCF than under LCF. Discrepancies 

may be primarily because of stress redistributions due to crack propagation. 

The A-end left tank head strain response to LCF buff was dissimilar from those observed at 

either the B-end left or right corners of the tank car. The vertical strain perpendicular to the seal 

weld (channel ALH3) was compressive under LCF buff, while the same response at both of the 

B-end corners was tensile. In addition, the relative magnitude of the vertical strain measuring 1 

inch outboard of the rosette (channel ALH4) was small, though the region was in tension like its 

counterparts at the B-end of the car. Surprisingly, these relative differences were observed under 

LCF buff only and not under any of the other three load types (LCF draft, upward VCF, and 

downward VCF). With this A-end exception, the strains perpendicular to the seal weld were 

tensile under LCF buff and downward VCF, and compressive under draft and upward loading. 
54 

Other qualitative observations that were made concerning the tank head strain measurements and 

stress calculations include: 

• Across the 1 inch between strain measurements perpendicular to the seal weld, vertical 

tank head sensitivity to LCF and VCF generally dropped by a factor of two (e.g., BRH4 ≈

0.5*BRH1). 

• The B-end corners of the car were more sensitive to LCF buff than to draft, with the 

reverse case at the A-end left. 

• At the B-end, upward and downward VCF caused about the same magnitudes of strain; 

upward was dominant at the A-end left. 

An interesting exercise that was briefly visited involved the calculation of the magnitudes and 

directions of the principal stresses for the three tank head rosettes at the various stages of the test. 

The relationship between this data and the incremental seal weld crack growth data, as well as an 

overall examination of the load redistribution phenomenon, has not been addressed in detail here. 

Some preliminary observations, however, were noted through these calculations and include the 

following: 

• Maximum principal stresses occurred in directions perpendicular to the seal welds for all 

load types at both B-end corners of the car; minimum principal stresses were parallel 

(longitudinal to the car). 

• Principal stress angles were similar between buff and draft, as they were between upward 

and downward loading, at the B-end. 

• Maximum principal stresses were oriented slightly inboard of vertical for VCF and 

slightly outboard for LCF at the B-end. 

• Principal stress magnitudes were similar for upward and downward VCF, but not for LCF 

buff and draft at the B-end. 

• At the B-end, VCF caused higher stress magnitudes than LCF. 

• The principal stress magnitudes and directions at the A-end left did not follow clear 

patterns, such as those at the B-end corners. 

• Upward VCF and LCF draft caused the highest stress magnitudes at the A-end left, 

contrary to the B-end corners. 

As demonstrated by these conclusions, several similarities existed between the B-end left and Bend right tank head strains. The A-end left, however, did not follow the same patterns. Benac et 

al. (1998) discussed the fractographic analysis that has been performed to date at each of these 

three corners, as well as crack growth rate behavior from the full-scale test. Of the three, the Aend left was the only strain-gaged corner of the car that had confirmed cracks growing through 

the tank head itself. In addition, recall that the workmanship at the A-end of the car was of a 

lesser quality than that of the B-end. The B-end left corner had cracks through seal weld 

material (a very porous, low-quality weld), and the B-end right corner was never opened up for 

further analysis. It is possible that this contributed to the observed stress patterns. Figures 29 

through 31 are schematic diagrams of the average relative relationships between the principal 

stresses for each of the three tank head measurements over the course of the test (these average 

values include all nine compliance strain surveys). The arrows indicate both relative magnitude 
55 

(distance from center) and whether the stresses were compressive (pointing toward the center) or 

tensile (pointing away from center); the axes indicate stress directions relative to the rosettes. 

The tables in Appendix D contain the actual calculated values for these schematics. 

Figure 29. Principal Stress Magnitudes and Directions at B-End Left Tank Head 

Figure 30. Principal Stress Magnitudes and Directions at B-End Right Tank Head
56 

Figure 31. Principal Stress Magnitudes and Directions at A-End Left Tank Head 

5.2.4 Sill Web Gradients and Summations 

A quantification of vertical sill web stress gradients was achieved with the strain gages at the Band A-end left corners of the test car. In addition, the web surface strain was measured at the Aend with a rosette. The data taken from these channels indicated that the stresses were for the 

most part linear for the test’s duration. However, repeatability appears to be poor, as the 

standard deviations between the sill web channels often had magnitudes as large as some of the 

individual measurements. This low repeatability was primarily due to the area’s low sensitivity 

to longitudinal and vertical coupler loading (the measurements taken were very small). Vertical 

strain sensitivities may have been low either because the gages were not located close enough to 

measure them or because the gages were not oriented to observe them (e.g., if the maximum 

principal strains were perpendicular to the gages and if the minimum principal strains were 

small, a vertical gradient may not have existed under the conditions tested). 

Though the measured strains were relatively small, certain patterns were distinguishable. With 

the possible exception of channel BLW1, vertical tension on the sill web was caused by LCF 

buff and downward VCF, while draft and upward loads caused vertical compression. However, 

LCF buff and upward VCF primarily caused compression on the surface at the location of the Aend left rosette, while draft and downward loads caused mostly tension. This is a direct result of 

the longitudinal orientation of the principal axes. Figure 32 provides the best illustration of these 

effects in the following schematic diagram. Like Figures 29 through 31, Figure 32 contains the 

average relative relationship between the principal stresses for all load cases at the A-end left sill 

web rosette location; the conventions used are the same. 
57 

Three qualitative observations that were made concerning the sill web strain measurements and 

stress calculations are: 

• Vertical sill web strain sensitivity to force appeared to increase as the measurement 

location moved upward toward the flange weld and outboard toward the striker. 

• Maximum principal stresses occurred in directions approximately parallel to the flange 

weld (longitudinal to the car) for all load types at the A-end left; minimum principal 

stresses were perpendicular. 

• LCF caused the highest von Mises stresses at the A-end left, though upward VCF was 

vertically dominant at the B-end left. 

Figure 32. Principal Stress Magnitudes and Directions at A-End Left Sill Web 

5.2.5 Sill Top Flange Gradients 

Much like the bending strains, the sill top flange sensitivities near the seal welds at the B- and Aend right corners of the car exhibited marked differences after the first compliance strain 

surveys. This effect was more dramatic at the A-end of the car, where the LCF buff response 

went from tensile to compressive. Again, this may result from stress redistribution within the 

structure, strain gage break-in, or a combination of both. As a result, overall linearity and 

repeatability at the A-end right was marginal, while both were good at the location of the B-end 

right flange gages. With the exception of the first strain survey, LCF buff and upward VCF 

caused longitudinal compression in the flange, while draft and downward loads caused 

longitudinal tension. 

Sill top flange qualitative observations include: 

• In general, LCF draft caused higher sill top flange longitudinal strain magnitudes than 

buff, though VCF sensitivity magnitudes were about the same, regardless of application 

direction. 
58 

• Higher longitudinal strains were observed at the flange edge (versus inboard). 

• The B-end right was more compliant than the A-end right flange. 

• Of the four load cases, draft caused the highest strain magnitudes at the A- and B- end 

right sill top flange measurements. 

Aside from the initial A-end right flange measurements, outliers of interest included channels 

BRF2 and BRF4. The strain gage BRF2 was damaged during an inspection after precracking; all 

measurements from that point on were rejected. The gage BRF4 showed a brief inconsistency 

during strain surveys at 0 and 50,000 spectrum miles. For both of these surveys, its sensitivity to 

the applied loads was about half of what it later achieved. 

5.3 System Control and Response 

As discussed in Section 3.6.1, the LCF and VCF spectra were applied to the test car in series 

without any corresponding bolster motions. The response of the actuators was collected as input 

into the DTA model. This system response data was collected at 50,000 spectrum-mile intervals, 

and rainflow cycle counted for convenience. Appendix E lists these cycle-counted forces. For 

simplicity, the histograms of Appendix E contain only two-dimensional information (force 

ranges versus number of counts) and do not contain the associated mean load levels. Over the 

course of the entire full-scale test, the mean levels were on target, and the ranges were slightly 

undershot at times. As expected, actuator transient response and ramp functions between cycles 

added many low-amplitude cycles back into the applied spectra. 

Because the actuator response spectra were used for the DTA validation, the various sources of 

differences between the inputs to and the response of the system were deemed acceptable. No 

additional time was spent further tuning the Simuloader actuators. For the DTA validation 

(Cardinal et al., 1998), the VCF response at the A-end of the test car (VCFW LVPU and UVPU) 

was used at both 150,000 and 250,000 spectrum-miles. The LCF response to the buff portion of 

the validation load schedule (LCF LLBUF and ULBUF) at 100,000 spectrum-miles was also 

used. 

5.4 Post-Test Analysis 

The final critical region inspection under a VCF preload, with the aid of a fiber optic scope, 

revealed that of the 30 suspected cracks A, B, P, U, W, and Y did not seem to exist. The other 

24 crack lengths were verified and modified, as Appendix B shows in the crack growth log. 

After the test car was removed from the Simuloader, the sills were sectioned and sent to SwRI 

for a fractographic analysis. The results of this analysis are contained in the companion report 

by Benac, et al. (1998). The fractographic evaluation included two types of assessments. The 

first was a general examination noting the fracture surface features, origin, and size. The cracks 

assessed solely in this fashion were cracks C, H, I, J, N, O, T, U, Z, AB, and the preflaws 

SW@FW-B and SW@FW-A. The second type of assessment was a more detailed evaluation of 

each fracture, including the precrack zone, marker band identification, and marker band 

measurement to determine crack growth rate. The cracks that were assessed in this fashion were 

cracks K, L, R, and the preflaw TH@SW. These latter four were chosen for detailed analyses 

because they contained the largest quantity of distinguishable fracture surface features, as 

assessed in the initial examination. 
59 

The report by Cardinal et al. (1998) discusses the actual DTA validation, along with the industry 

DTA efforts as a whole. To some extent, validation is a misnomer as the results of this test were 

used to modify the input parameters to the DTA model, in addition to validating those previously 

assumed. The following response data files (rainflow cycle-counted) were used for this effort: 

• VCFW LVPU at 150,000 and 250,000 spectrum-miles 

• VCFW UVPU at 150,000 and 250,000 spectrum-miles 

• LCF LLBUF at 100,000 spectrum-miles 

• LCF ULBUF at 100,000 spectrum-miles 
60 
61 

6. Significant Observations 

This final section summarizes key observations from the full-scale test. Other conclusions 

concerning recent cooperative efforts of the government and the tank car industry can be found 

in five additional reports. Cogburn (1995) discussed the most recent tank car OTR test 

procedures and the data that was acquired to be put into the AAR-MSRP. McKeighan et al. 

(1997) discussed the coupon tests that were performed to investigate both spectrum truncation 

and clipping. A proprietary report by Williams (1997) reviews the pre- and mid-test FEA of the 

orphan test car. The details from the full-scale damage tolerance validation test were covered in 

this document. The post-test fractographic efforts, full-scale fatigue crack growth rates, and their 

implications were documented by Benac et al. (1998) in a companion report. Cardinal et al. 

(1998) details the actual tank car DTA program and its validation, using the information from the 

full-scale test and the post-test fractography. 

6.1 OTR and Coupon Testing 

• AAR REPOS data for 100-ton tank cars now includes a combination of 1986 and 1994 

FEEST data for LCF but only 1994 data for VCF. These are the two primary load spectra 

employed by the tank car DTA program. 

• It was assumed that if the ratio of simulated mileage per spectrum pass to the total test 

mileage is small (in this case, 1/30), the test load sequence is effectively randomized for 

fatigue crack growth mechanisms, regardless of the sequence within each pass. 

• Preliminary coupon tests indicated that for common tank car steels, 4 to 5 ksi may be an 

acceptable truncation level in accelerated testing and that peak load clipping may have 

minimal effects on crack growth behavior. Additional testing is recommended. 

6.2 Orphan Tank Car NATX 22746 

• The orphan test car had neither head pads nor head braces and no previous record of 

parent metal crack repairs. Though different from most cars in service, this was deemed 

acceptable for the analytical model validations. It arrived at TTC with approximately 

300,000 miles of accumulated usage and had been in storage for approximately 8 years. 

• For the initial inspections of the stub sill critical regions, portions of the jacket were 

removed, and the seal weld areas were lightly sandblasted. The rust and scale were as 

much as 1/8-inch thick in some areas, which hindered visual inspection. 

• Despite evidence of poor workmanship in several areas on the car, initial visual 

inspections did not reveal any cracks in the critical stub sill regions highlighted by the 

SS-II database and FEA of the test car. 

6.3 Pre-Test DTA 

• In general, the FEA of the orphan test car predicted stub sill stress concentrations at the 

same locations identified by the SS-II database. 
62 

• The car’s FEA was conservative by a factor of 1 to 3, an engineering estimate based on 

36 strain and displacement measurements from 6 carbody compliance tests and a linear 

FEA of the uncracked structure. This nominal weighted-average factor, however, does 

not distinguish changes in carbody compliance as cracks progressed throughout the 

structure. This issue warrants further study. 

• The initial LEFM analysis of the car, based on the conservative FEA, predicted a 

necessary duration of about 300,000 spectrum-miles to achieve sufficient crack growth 

for model validation. Crack aspect ratios (a critical parameter) were assumed. 

6.4 Preflawing and Precracking 

• A relatively small amount of confirmed crack initiation and growth was observed at the 

mechanically inserted flaws during precracking X an unexpected result. 

• In retrospect, precracking was occurring elsewhere on the car, at stress concentrations 

that were sometimes more difficult to observe; crack E motivated the suspension of 

precracking. 

• A total of 156,500 precracking cycles were applied to the car with a maximum force of 

80 percent peak spectrum load, resulting in deep crack growth through the thickness in 

regions later sectioned for fractographic analysis. Visual surface measurements did not 

reveal this relative severity during the precracking phase of the test. 

6.5 Validation Load Schedule 

• From the 10,000-mile DTA load schedule, all cycles that caused critical region stresses 

less than or equal to 5.1 ksi (based on the FEA) were truncated for the validation drive 

files, resulting in a 97.3 percent reduction in total cycle count or 16,100 spectrum cycles 

for each 10,000 spectrum-mile pass.

• Sinusoidal drive signals for each actuator were created in an ordered random fashion. 

Ramp functions between cycles and actuator transient response caused the addition of 

many low-amplitude cycles back into the applied spectrum and increased test time.

• For the 300,000 spectrum-mile validation test, LCF was applied at 2 hertz and VCF at 5 

hertz. These frequencies were maximized during the initial system characterization.

6.6 Marker Band Application 

• Beach marks (striations) on the fracture surface of the VCF stud that failed at 293,000 

spectrum-miles indicated marker banding success. Constant-amplitude marker bands 

were applied to the car at 20,000 spectrum-mile intervals (total of 375,000 throughout the 

test) with a load ratio of 0.8 and a maximum of 90 percent peak spectrum load. 

• The marker banding techniques used proved effective for creating a periodic 

fractographic record of crack growth through the thickness of the material, in the regions 

analyzed. 
63 

6.7 Spectrum Crack Growth 

• Thirty suspected cracks were monitored throughout the test; five were from preflaws. 

• Ten suspected cracks and three preflaws (through the thickness) were given a cursory 

fractographic analysis. Three cracks and one preflaw were examined more thoroughly. 

• Two of the five suspected preflaw cracks were proven to be true fatigue cracks; these 

were C and D from the tank head preflaw (TH@SW) at the A-end left corner. 

• Visual measurements of surface crack length made during the test agreed well with the 

fractographic results from the cracks analyzed (cracks K, L, R, and preflaw TH@SW), 

including those made with dye penetrant and no preload after 70,000 spectrum-miles. 

• At all 4 corners of the car, increased crack growth rates (and some new cracks) were 

observed on the surface after the VCF amplification at 200,000 spectrum-miles; sufficient 

growth for DTA model validation was achieved by 300,000 spectrum-miles. 

• The fiber optic scope worked well for the detection and video documentation of cracks in 

otherwise unobservable locations, but it proved to be difficult to manage for the actual 

measurement of surface crack length. 

6.8 Carbody Compliance 

• A vertical reaction inside the sill near the striker may have caused the stub sills to bend 

irregularly under buff loading, rather than as they would under downward loads. This 

possibility of s-shape versus c-shape bending needs further investigation. 

• Measurement linearity and repeatability varied; this result may be a reflection of stress 

redistribution due to load path changes as cracks propagated through the structure. 

• In the areas measured, upward VCF and LCF draft were more dominant in strain 

sensitivity (these load directions caused higher strain magnitudes) than their downward 

and buff counterparts. In general, downward and buff are dominant coupler loads in 

driving crack growth, as they often result in critical region tension. 

• Either relatively poor workmanship or cracks in the A-end left tank head parent metal (in 

the upper toe of the seal weld) appeared to skew the nearby principal stress directions 

from the case at the B-end left, where the seal weld cracks were in weld metal and the 

welds were of better overall quality. 

• The B-end right stress magnitudes and directions were similar to the B-end left, but it was 

not opened for analysis. 

• The vertical tank head strains typically dropped by a factor of 2 in the 1-inch distance 

between strain gages. 

• The vertical sill web strains (at the B- and A-ends of the car) were very small; the 

principal stress axes for VCF and LCF was longitudinal along the flange weld. 

• Higher longitudinal strain magnitudes were observed at the edge of the sill top flange at 

both the B- and A-end right corners, when compared with the strains measured inboard 

on the flange surface. 
64 

• Strain channel BRF2 (B-end right sill top flange edge, nearest seal weld) was the only 

data channel lost permanently during the full-scale test. 

6.9 VCF Placement and Amplification 

• Due to actuator placement, the applied VCF moment to the seal weld was approximately 

half of the extreme OTR possibility (the applied shear was not affected). This moment 

arm reduction, as well as truncation, clipping, actuator transient response, and lack of 

bolster motions (i.e., the fact that this was not an OTR simulation), were all deemed 

acceptable simplification techniques for the DTA model validation. All of these factors 

were accounted for in the car’s analyses. 

• To encourage crack growth in the wake of the discovery that the FEA was conservative, 

the VCF inputs were amplified at 200,000 spectrum-miles by a factor of two (to correct 

for the OTR moment arm loss). Because the applied shear was doubled from the OTR 

situation, the inputs were clipped at 55 kips, based on tank car design criteria and A-end 

actuator capacity. This was done to prevent catastrophic sill failure, as well as to provide 

VCF symmetry at both ends of the car. 

6.10 DTA Validation 

• The full-scale test and corresponding DTA results, though not directly transferable to 

other stub sill tank car designs, illustrated the general applicability of the damage 

tolerance approach to tank car design and life extension. 

• Sufficient stress and crack growth results have been obtained for the DTA analytical 

model validation. 
65 

References 

Barsom, J.M., and Rolfe, S.T., 1987, Fracture and Fatigue Control in Structures, 2nd Edition, 

Prentice-Hall. 

Benac, D.J., McKeighan, P.C., and Cardinal, J.W., 1998, “Fractographic Analysis of Cracks 

Generated During a Full-Scale Railroad Tank Car Fatigue Test,” Final Report 06-8840, 

Southwest Research Institute, San Antonio, TX. 

Broek, D., 1989, The Practical Use of Fracture Mechanics, Kluwer. 

Cardinal, J.W., McKeighan, P.C., and Hudak, S.J., 1998, “Damage Tolerance Analysis of Tank 

Car Stub-Sill Cracking,” Final Report 06-6965, Southwest Research Institute, San Antonio, TX. 

Cackovic, D.L., 1993, “Tank Car Fatigue Crack Growth Test,” Technical Report 

DOT\FRA\ORD\93-10, Transportation Technology Center, Inc., Pueblo, CO. 

Cogburn, L.T., 1995, “Stub-Sill Tank Car Research Project: Results of a 15,000-Mile Over-TheRoad Test,” Technical Report FRA\ORD\95-11, Transportation Technology Center, Inc., 

Pueblo, CO. 

Damage Tolerance Assessment Handbook, Volumes I and II, 1993, DOT-VNSTC-FAA-93-13.I. 

Fatigue Design Handbook, AE-10, 1988, Society of Automotive Engineers, Warrendale, PA. 

Forman, R.G., et al., 1994, “NASA/FLAGRO Fatigue Crack Growth Computer Program Version 

2.0 Revision A,” JSC-22267A, National Aeronautics and Space Administration. 

Gallagher, J.P., et al., 1984, USAF Damage Tolerant Design Handbook, AFWAL-TR-82-3073. 

Hattery, B.K., et al., 1997, “The Minutiae of Tank Car Structural Integrity,” Proceedings, 

International Symposium on Railroad Tank Cars, Indianapolis, IN. 

Hudak, S.J., Burnside, O.H., and Chan, K.S., 1985, “Analysis of Corrosion Fatigue in Welded 

Tubular Joints,” ASME Journal of Energy Resources Technology, Volume 107. 

McKeighan, P.C., Smith, K.B., and Cardinal, J.W., 1997, “Load Interaction Effects in Coupon 

Fatigue Tests Using a Railroad Tank Car Spectrum,” Proceedings, ASME 1997 International 

Mechanical Engineering Congress and Exposition, Dallas, TX. 

Orringer, O., 1994, “Validation of Simulated Service Load Spectra for Crack Propagation 

Testing in Full-Scale Structures,” Working Paper, Volpe National Transportation Systems 

Center, Washington, DC. 

Przybylinski, P., and Halcomb, S., 1977, “Interim AAR Guidelines for Fatigue Analysis of 

Freight Cars,” Report R-245, Association of American Railroads, Pueblo, CO. 

Richmond, S., and Sneed, W.H., 1981, “Freight Equipment Environmental Sampling Tests: 

Center Plate and Side Bearing Loads for Analysis,” Proceedings, International Conference on 

Wheel/Rail Load and Displacement Measurement Techniques, Cambridge, MA. 

Sharma, V., 1990, “Freight Car Fatigue: Coal Car Simuloader Demonstration Test,” Report R747, Association of American Railroads, Pueblo, CO. 
66 

Sharma, V., and Punwani, S.K., 1984, “Freight Equipment Environmental Sampling Test 

Description and Results,” Proceedings, ASME Rail Transportation Division Spring Conference, 

Chicago, IL. 

Stub-Sill Inspection Database, SS-2, 1996, Association of American Railroads–Railway Progress 

Institute, Washington, DC. 

Stone, D.H., and Cardinal, J.W., 1997, “Application of Damage Tolerance Principles to Stub-Sill 

Tank Car Cracking,” Proceedings, 6th International Heavy Haul Conference, Cape Town, South 

Africa. 

Williams, M.R., 1997, “AMF Coiled Tank Car Damage Tolerance Analysis,” Design Report 

1415, ACF Industries, Inc., St. Charles, MO. 
67 

Acronyms 

AAR Association of American Railroads 

ARI American Railcar Industries 

CMA Chemical Manufacturers Association 

DTA damage tolerance analysis 

FEA finite element analysis 

FEEST Freight Equipment Environmental Sampling Test 

FRA Federal Railroad Administration 

GE General Electric Capital Railcar Services 

LCF longitudinal coupler force 

LLCF loaded longitudinal (coupler force), buff only 

LLDFT loaded longitudinal (coupler force), draft only 

LVPU loaded vertical (coupler force), positive is up 

OTR over-the-road 

REPOS Road Environment Percentage Occurrence System 

RPI Railway Progress Institute 

SSWG Stub-Sill Working Group 

SwRI Southwest Research Institute 

TTC Transportation Technology Center 

TTCI Transportation Technology Center, Inc. 

ULBUF unloaded longitudinal (coupler force), buff only 

ULDFT unloaded longitudinal (coupler force), draft only 

UVPU unloaded vertical (coupler force), positive is up 

VCF vertical coupler force 
68 
69 

Glossary 

Beach Mark: Beach marks are striations on the fracture surface of a fatigue crack, 

perpendicular to the direction of crack growth. In general, they result from 

variations or irregularities in the magnitudes and load ratios 

(minimum/maximum) of applied stresses that propagated the crack through 

the material. 

Clipping: During typical laboratory simulations, loads measured in the field are applied 

to the structures they were collected from/for. Due to various test rig 

limitations, dynamic loads observed in the field are not always recreated 

precisely in the laboratory. If a load magnitude is reduced during a 

simulation, it is said to be clipped. A clipped event is reduced in magnitude 

but not removed from the spectrum. 

Coherence: For linear systems, the coherence function can be interpreted as the fractional 

portion of the mean square value at the response that is contributed by the 

input at discrete frequencies. It can be used to measure the strength of the 

linear relationship between two system vibrations across a bandwidth. The 

concept behind coherence is similar to that of statistical correlation. 

Compliance: As it is used here, compliance is essentially a synonym for linear stiffness or 

the strain of an elastic body expressed as a function of the force producing the 

strain. Compliance is used to indicate structural stiffness in three-dimensional 

space at all measurement locations, rather than specifically along any one axis 

at any single location. 

Marker Band: A marker band is an intentional beach mark applied to a test specimen at 

known intervals, so that crack growth information along the fracture surface 

may be obtained after testing is completed. In the case of this program, 

periodic marker bands were applied through constant amplitude cyclic 

loading, to create features visibly different from those created during the 

variable amplitude spectrum loading. 

Precrack: The term precrack refers to the cyclic loading of a test specimen to drive 

cracks from the stress concentrations induced by a preflaw. In the case of this 

program, constant amplitude loads were used along two axes of the test 

specimen (longitudinal and vertical) to accomplish this. 

Preflaw: The term preflaw refers to the mechanical insertion of a flaw into a test 

specimen in a region of high stress. As the specimen is cyclically loaded, 

cracks are expected to grow into the material from the stress concentrations 

induced at the corners of the flaw. 

Rainflow: For highly irregular variations of load with time, cycle-counting techniques 

have been developed to isolate and define cycles so that Palmgren-Miner 

cumulative damage theory can be employed. Rainflow cycle counting has 

been preferred by the railroad industry to count the peaks and valleys of any 
70 

load history and produce fatigue spectra for use in stress- and strain-life 

calculations. 

Spectrum: A spectrum is a description of a quantity in terms of any function of 

frequency. In the case of the AAR’s Manual of Standards and Recommended 

Practices, the term fatigue spectra refers to the histograms of freight car input 

load data, which are the result of rainflow counting time history data from 

several OTR operating environment tests. 

Transient: Transient data result from short-duration nonstationary phenomena with a 

clearly defined beginning and end. Transient actuator response refers to the 

portion of the actuator response that is not commanded but is a result of its 

mechanical limitations. This error is observed as dynamic over- and undershooting of target values. 

Truncation: Spectra obtained from field measurements typically contain large numbers of 

ranges with small magnitudes. Since the number of events generally 

decreases rapidly as the range magnitude increases, test times can be reduced 

to a small fraction of full spectra requirements if the small ranges are 

excluded. This type of test compression is commonly referred to as 

truncation. 
A-1 

Appendix A. 

Relevant Portions of SwRI 10,000-Mile Tank Car Load Schedule 

A-1. Loaded Tank VCF Events 

Loaded 100-Ton Tank Car VCF 10,000-Mile Scaled DTA Load Schedule 

Positive = Upward Loading Unloaded/Loaded Ratio = 1.06 

VCF—LVPU 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

0.2011 -41.25 61.25

0.2011 -28.75 58.75

0.2011 -18.75 51.25

0.2011 -18.75 48.75

0.2011 3.75 46.25

0.2011 -1.25 46.25

0.2011 -48.75 46.25

0.2011 38.75 41.25

0.2011 -3.75 41.25

0.2011 -13.75 41.25

0.2011 33.75 38.75

0.2011 3.75 38.75

0.2011 -11.25 38.75

0.2011 -21.25 38.75

0.2011 -26.25 38.75

0.2011 -33.75 38.75

0.2011 -36.25 38.75

0.2011 -38.75 38.75

0.2011 -48.75 38.75

0.8045 33.75 36.25

0.2011 31.25 36.25

0.2011 6.25 36.25

0.2011 3.75 36.25

0.4022 -8.75 36.25

0.2011 -13.75 36.25

0.2011 -26.25 36.25

0.2011 -31.25 36.25

2.6145 31.25 33.75

0.2011 26.25 33.75

0.2011 1.25 33.75

0.2011 -1.25 33.75
A-2 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

0.4022 -3.75 33.75

0.2011 -13.75 33.75

0.2011 -18.75 33.75

0.2011 -23.75 33.75

0.2011 -41.25 33.75

1.2067 28.75 31.25

1.0056 26.25 31.25

0.4022 6.25 31.25

1.0056 3.75 31.25

0.2011 -1.25 31.25

0.4022 -3.75 31.25

0.4022 -6.25 31.25

0.2011 -11.25 31.25

0.6033 -13.75 31.25

0.4022 -16.25 31.25

0.2011 -18.75 31.25

0.2011 -23.75 31.25

0.2011 -26.25 31.25

0.2011 -28.75 31.25

0.2011 -31.25 31.25

0.6033 -33.75 31.25

0.2011 -43.75 31.25

18.3015 26.25 28.75

0.6033 23.75 28.75

0.4022 21.25 28.75

0.2011 13.75 28.75

0.2011 6.25 28.75

0.8045 3.75 28.75

0.6033 1.25 28.75

0.4022 -1.25 28.75

0.2011 -6.25 28.75

0.4022 -8.75 28.75

0.2011 -11.25 28.75

0.8045 -16.25 28.75

0.8045 -18.75 28.75

0.4022 -21.25 28.75

0.4022 -23.75 28.75
A-3 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

0.2011 -26.25 28.75 

0.4022 -28.75 28.75 

0.2011 -31.25 28.75 

0.2011 -36.25 28.75 

0.2011 -51.25 28.75 

15.687 23.75 26.25 

7.6424 21.25 26.25 

0.2011 18.75 26.25 

0.4022 13.75 26.25 

1.0056 11.25 26.25 

0.4022 8.75 26.25 

0.8045 6.25 26.25 

1.6089 3.75 26.25 

0.6033 1.25 26.25 

1.6089 -1.25 26.25 

0.8045 -3.75 26.25 

1.6089 -6.25 26.25 

1.0056 -8.75 26.25 

1.2067 -11.25 26.25 

0.8045 -13.75 26.25 

1.6089 -16.25 26.25 

0.6033 -18.75 26.25 

0.4022 -21.25 26.25 

1.0056 -23.75 26.25 

0.4022 -26.25 26.25 

0.2011 -28.75 26.25 

0.4022 -31.25 26.25 

0.2011 -33.75 26.25 

38.8153 21.25 23.75 

36.8041 18.75 23.75 

1.0056 16.25 23.75 

0.6033 13.75 23.75 

0.6033 11.25 23.75 

0.2011 8.75 23.75 

2.8156 6.25 23.75 

3.0167 3.75 23.75 

1.6089 1.25 23.75 
A-4 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

0.8045 -1.25 23.75 

0.4022 -3.75 23.75 

1.0056 -6.25 23.75 

0.8045 -8.75 23.75 

1.2067 -11.25 23.75 

1.0056 -13.75 23.75 

1.2067 -16.25 23.75 

1.2067 -18.75 23.75 

1.0056 -21.25 23.75 

0.6033 -23.75 23.75 

0.8045 -26.25 23.75 

0.4022 -28.75 23.75 

0.4022 -31.25 23.75 

0.2011 -38.75 23.75 

65.7647 18.75 21.25 

38.413 16.25 21.25 

1.2067 13.75 21.25 

5.4301 11.25 21.25 

7.6424 8.75 21.25 

4.2234 6.25 21.25 

5.229 3.75 21.25 

2.4134 1.25 21.25 

3.419 -1.25 21.25 

2.2123 -3.75 21.25 

2.0112 -6.25 21.25 

4.4245 -8.75 21.25 

2.6145 -11.25 21.25 

1.81 -13.75 21.25 

2.4134 -16.25 21.25 

3.0167 -18.75 21.25 

0.8045 -21.25 21.25 

0.8045 -23.75 21.25 

0.2011 -26.25 21.25 

0.2011 -38.75 21.25 

303.282 16.25 18.75 

16.2903 13.75 18.75 

22.9272 11.25 18.75 
A-5 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

18.9048 8.75 18.75

8.648 6.25 18.75

9.2513 3.75 18.75

11.6647 1.25 18.75

7.6424 -1.25 18.75

7.039 -3.75 18.75

6.2346 -6.25 18.75

5.4301 -8.75 18.75

3.8212 -11.25 18.75

3.0167 -13.75 18.75

2.8156 -16.25 18.75

1.6089 -18.75 18.75

0.4022 -21.25 18.75

0.8045 -23.75 18.75

0.4022 -26.25 18.75

0.6033 -28.75 18.75

0.2011 -31.25 18.75

0.2011 -33.75 18.75

0.2011 -41.25 18.75

346.5218 13.75 16.25

163.5068 11.25 16.25

46.6588 8.75 16.25

34.5918 6.25 16.25

33.3852 3.75 16.25

25.9439 1.25 16.25

25.9439 -1.25 16.25

14.0781 -3.75 16.25

21.1171 -6.25 16.25

14.2792 -8.75 16.25

10.6591 -11.25 16.25

5.8323 -13.75 16.25

9.0502 -16.25 16.25

3.6201 -18.75 16.25

2.0112 -21.25 16.25

1.4078 -23.75 16.25

2.6145 -26.25 16.25

0.6033 -28.75 16.25

0.2011 -31.25 16.25
A-6 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

0.2011 -33.75 16.25

0.2011 -41.25 16.25

441.046 11.25 13.75

407.6609 8.75 13.75

100.9599 6.25 13.75

89.4963 3.75 13.75

58.1223 1.25 13.75

49.0722 -1.25 13.75

41.4298 -3.75 13.75

33.5863 -6.25 13.75

20.916 -8.75 13.75

17.6982 -11.25 13.75

13.877 -13.75 13.75

11.4636 -16.25 13.75

6.4357 -18.75 13.75

2.8156 -21.25 13.75

2.0112 -23.75 13.75

1.0056 -26.25 13.75

0.4022 -28.75 13.75

0.2011 -38.75 13.75

814.7184 8.75 11.25

862.1816 6.25 11.25

292.0195 3.75 11.25

164.7135 1.25 11.25

147.8198 -1.25 11.25

103.1722 -3.75 11.25

85.0718 -6.25 11.25

44.4465 -8.75 11.25

30.7707 -11.25 11.25

18.1004 -13.75 11.25

10.0558 -16.25 11.25

5.4301 -18.75 11.25

3.0167 -21.25 11.25

2.0112 -23.75 11.25

0.4022 -26.25 11.25

0.2011 -28.75 11.25

0.4022 -31.25 11.25
A-7 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

0.2011 -36.25 11.25

0.2011 -38.75 11.25

7358.0073 6.25 8.75

1655.783 3.75 8.75

831.2098 1.25 8.75

552.4639 -1.25 8.75

291.4162 -3.75 8.75

194.2775 -6.25 8.75

94.122 -8.75 8.75

50.48 -11.25 8.75

31.374 -13.75 8.75

18.3015 -16.25 8.75

6.4357 -18.75 8.75

3.2178 -21.25 8.75

1.81 -23.75 8.75

1.81 -26.25 8.75

0.2011 -28.75 8.75

0.2011 -31.25 8.75

0.2011 -33.75 8.75

0.2011 -43.75 8.75

17374.3574 3.75 6.25

13971.8877 1.25 6.25

3534.2004 -1.25 6.25

1142.9387 -3.75 6.25

595.1004 -6.25 6.25

192.0652 -8.75 6.25

101.3621 -11.25 6.25

55.5078 -13.75 6.25

28.5584 -16.25 6.25

8.4468 -18.75 6.25

5.0279 -21.25 6.25

4.2234 -23.75 6.25

1.4078 -26.25 6.25

1.0056 -28.75 6.25

0.2011 -31.25 6.25

0.2011 -46.25 6.25

43753.0508 1.25 3.75

33361.2188 -1.25 3.75
A-8 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

4204.5181 -3.75 3.75

1334.1993 -6.25 3.75

375.6835 -8.75 3.75

149.2276 -11.25 3.75

76.4238 -13.75 3.75

33.3852 -16.25 3.75

16.2903 -18.75 3.75

8.4468 -21.25 3.75

1.6089 -23.75 3.75

0.4022 -26.25 3.75

0.6033 -28.75 3.75

0.2011 -31.25 3.75

0.2011 -38.75 3.75

71885.4688 -1.25 1.25

39722.0977 -3.75 1.25

3416.3469 -6.25 1.25

743.3224 -8.75 1.25

295.8407 -11.25 1.25

122.2781 -13.75 1.25

44.0443 -16.25 1.25

12.4692 -18.75 1.25

5.0279 -21.25 1.25

0.8045 -23.75 1.25

1.2067 -26.25 1.25

0.4022 -28.75 1.25

0.8045 -31.25 1.25

0.4022 -36.25 1.25

44499.3906 -3.75 -1.25

22241.3496 -6.25 -1.25

1412.031 -8.75 -1.25

439.236 -11.25 -1.25

167.1269 -13.75 -1.25

48.2677 -16.25 -1.25

13.2736 -18.75 -1.25

7.039 -21.25 -1.25

3.419 -23.75 -1.25

1.81 -26.25 -1.25

0.4022 -28.75 -1.25
A-9 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

0.4022 -36.25 -1.25 

62314.3906 -6.25 -3.75 

2115.3315 -8.75 -3.75 

561.1119 -11.25 -3.75 

222.4336 -13.75 -3.75 

44.8487 -16.25 -3.75 

18.9048 -18.75 -3.75 

6.2346 -21.25 -3.75 

1.81 -23.75 -3.75 

1.2067 -26.25 -3.75 

0.2011 -36.25 -3.75 

0.2011 -41.25 -3.75 

3547.2729 -8.75 -6.25 

878.0697 -11.25 -6.25 

179.9983 -13.75 -6.25 

46.2565 -16.25 -6.25 

11.6647 -18.75 -6.25 

3.419 -21.25 -6.25 

1.6089 -23.75 -6.25 

0.2011 -26.25 -6.25 

0.6033 -28.75 -6.25 

0.2011 -31.25 -6.25 

0.2011 -36.25 -6.25 

1031.923 -11.25 -8.75 

457.9397 -13.75 -8.75 

41.4298 -16.25 -8.75 

11.4636 -18.75 -8.75 

6.4357 -21.25 -8.75 

2.2123 -23.75 -8.75 

1.0056 -26.25 -8.75 

0.2011 -28.75 -8.75 

0.4022 -31.25 -8.75 

0.2011 -38.75 -8.75 

654.2283 -13.75 -11.25 

219.8191 -16.25 -11.25 

11.0613 -18.75 -11.25 

3.2178 -21.25 -11.25 

0.8045 -23.75 -11.25 
A-10 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

0.4022 -26.25 -11.25 

0.2011 -28.75 -11.25 

438.0293 -16.25 -13.75 

9.6535 -18.75 -13.75 

2.2123 -21.25 -13.75 

1.6089 -23.75 -13.75 

0.2011 -26.25 -13.75 

0.2011 -28.75 -13.75 

0.2011 -31.25 -13.75 

96.7365 -18.75 -16.25 

21.7205 -21.25 -16.25 

1.0056 -23.75 -16.25 

0.4022 -26.25 -16.25 

0.2011 -31.25 -16.25 

24.9383 -21.25 -18.75 

27.7539 -23.75 -18.75 

0.6033 -26.25 -18.75 

0.2011 -28.75 -18.75 

20.5138 -23.75 -21.25 

10.6591 -26.25 -21.25 

11.0613 -26.25 -23.75 

0.4022 -28.75 -23.75 

3.8212 -28.75 -26.25 

1.4078 -31.25 -26.25 

1.2067 -31.25 -28.75 

0.2011 -33.75 -28.75 

0.4022 -33.75 -31.25 

0.2011 -36.25 -31.25 

0.2011 -43.75 -31.25 

0.2011 -36.25 -33.75 

0.8045 -38.75 -36.25 

0.2011 -43.75 -41.25 

0.2011 -48.75 -46.25 
A-11 

A-II. Unloaded Tank VCF Events 

Unloaded 100-Ton Tank Car VCF 

10,000-Mile Scaled DTA Load Schedule 

Positive = Upward Loading Unloaded/Loaded Ratio = 1.06 

VCF—UVPU 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

1.2314 -33.75 33.75

1.2314 -11.25 31.25

1.2314 26.25 28.75

1.2314 23.75 28.75

1.2314 -13.75 28.75

1.2314 -18.75 28.75

1.2314 -41.25 28.75

1.2314 18.75 26.25

1.2314 3.75 26.25

2.4628 -6.25 26.25

1.2314 -8.75 26.25

1.2314 -11.25 26.25

1.2314 -13.75 26.25

1.2314 -26.25 26.25

1.2314 21.25 23.75

2.4628 18.75 23.75

1.2314 6.25 23.75

2.4628 3.75 23.75

2.4628 1.25 23.75

1.2314 -1.25 23.75

4.9256 -6.25 23.75

1.2314 -8.75 23.75

3.6942 -11.25 23.75

1.2314 -13.75 23.75

2.4628 -16.25 23.75

2.4628 -18.75 23.75

1.2314 -23.75 23.75

2.4628 16.25 21.25

1.2314 11.25 21.25

4.9256 3.75 21.25

1.2314 1.25 21.25

3.6942 -1.25 21.25

1.2314 -6.25 21.25

2.4628 -8.75 21.25
A-12 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

3.6942 -11.25 21.25 

1.2314 -13.75 21.25 

2.4628 -16.25 21.25 

1.2314 -18.75 21.25 

2.4628 -21.25 21.25 

1.2314 -26.25 21.25 

1.2314 -31.25 21.25 

2.4628 16.25 18.75 

2.4628 13.75 18.75 

2.4628 6.25 18.75 

17.2395 3.75 18.75 

7.3884 1.25 18.75 

8.6198 -1.25 18.75 

7.3884 -3.75 18.75 

6.157 -6.25 18.75 

7.3884 -8.75 18.75 

1.2314 -11.25 18.75 

2.4628 -13.75 18.75 

4.9256 -16.25 18.75 

20.9337 13.75 16.25 

61.5698 11.25 16.25 

23.3965 8.75 16.25 

11.0826 6.25 16.25 

67.7267 3.75 16.25 

23.3965 1.25 16.25 

25.8593 -1.25 16.25 

12.314 -3.75 16.25 

14.7767 -6.25 16.25 

16.0081 -8.75 16.25 

16.0081 -11.25 16.25 

9.8512 -13.75 16.25 

6.157 -16.25 16.25 

2.4628 -18.75 16.25 

2.4628 -21.25 16.25 

1.2314 -23.75 16.25 

130.5279 11.25 13.75 

41.8674 8.75 13.75 
A-13 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

35.7105 6.25 13.75

296.7662 3.75 13.75

70.1895 1.25 13.75

43.0988 -1.25 13.75

36.9419 -3.75 13.75

34.4791 -6.25 13.75

29.5535 -8.75 13.75

18.4709 -11.25 13.75

11.0826 -13.75 13.75

8.6198 -16.25 13.75

2.4628 -18.75 13.75

2.4628 -21.25 13.75

1.2314 -23.75 13.75

86.1977 8.75 11.25

385.4267 6.25 11.25

1422.2614 3.75 11.25

325.0883 1.25 11.25

167.4697 -1.25 11.25

130.5279 -3.75 11.25

64.0325 -6.25 11.25

32.0163 -8.75 11.25

32.0163 -11.25 11.25

13.5453 -13.75 11.25

12.314 -16.25 11.25

3.6942 -18.75 11.25

1.2314 -21.25 11.25

1.2314 -26.25 11.25

3029.2319 6.25 8.75

7569.3857 3.75 8.75

1428.4183 1.25 8.75

795.4812 -1.25 8.75

330.0139 -3.75 8.75

145.3046 -6.25 8.75

50.4872 -8.75 8.75

19.7023 -11.25 8.75

20.9337 -13.75 8.75

6.157 -16.25 8.75
A-14 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

2.4628 -18.75 8.75 

1.2314 -28.75 8.75 

12384.1406 3.75 6.25 

14930.665 1.25 6.25 

4094.3887 -1.25 6.25 

1036.8346 -3.75 6.25 

264.7499 -6.25 6.25 

89.8918 -8.75 6.25 

66.4953 -11.25 6.25 

18.4709 -13.75 6.25 

4.9256 -16.25 6.25 

2.4628 -18.75 6.25 

44421.3477 1.25 3.75 

21567.8848 -1.25 3.75 

3644.9294 -3.75 3.75 

662.4905 -6.25 3.75 

190.8662 -8.75 3.75 

55.4128 -11.25 3.75 

18.4709 -13.75 3.75 

6.157 -16.25 3.75

2.4628 -18.75 3.75 

1.2314 -21.25 3.75 

14385.1572 -1.25 1.25 

6490.6836 -3.75 1.25 

1006.0498 -6.25 1.25 

369.4185 -8.75 1.25 

98.5116 -11.25 1.25 

24.6279 -13.75 1.25 

4.9256 -16.25 1.25 

5357.7998 -3.75 -1.25 

3372.791 -6.25 -1.25 

810.258 -8.75 -1.25

136.6849 -11.25 -1.25 

19.7023 -13.75 -1.25 

7.3884 -16.25 -1.25

1.2314 -33.75 -1.25

3234.875 -6.25 -3.75 
A-15 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

1955.4554 -8.75 -3.75

189.6348 -11.25 -3.75

7.3884 -13.75 -3.75

4.9256 -16.25 -3.75

1225.2382 -8.75 -6.25

158.85 -11.25 -6.25

23.3965 -13.75 -6.25

8.6198 -16.25 -6.25

35.7105 -11.25 -8.75

17.2395 -13.75 -8.75

3.6942 -16.25 -8.75

11.0826 -13.75 -11.25

2.4628 -16.25 -11.25

1.2314 -21.25 -11.25

2.4628 -16.25 -13.75

1.2314 -18.75 -13.75

1.2314 -18.75 -16.25

1.2314 -23.75 -16.25
A-16 

A-III. Loaded Tank LCF Buff Events 

Loaded 100-Ton Tank Car Longitudinal Buff Coupler Force 

10,000-Mile Scaled DTA Load Schedule 

Negative = Buff Loading Unloaded/Loaded Ratio = 1.06 

LCF—LLBUF 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

0.4074 -430 0 

0.8149 -370 0 

178.4529 -50 0 

98.801 -70 0 

71.096 -90 0 

17.1119 -150 0 

0.8149 -330 0 

44.6132 -110 0 

12.6302 -170 0 

4.4817 -210 0 

2.6483 -250 0 

0.2037 -470 0 

1280.7458 -20 0 

243.4374 -40 0 

130.1728 -60 0 

11.0005 -180 0 

3.0557 -220 0 

0.2037 -460 0 

0.4074 -480 0 

12.4265 -500 0 

25.0567 -130 0 

3.2594 -270 0 

2.0371 -290 0 

51.9469 -100 0 

456.5216 -30 0 

3.8706 -230 0 

0.4074 -310 0 

0.4074 -350 0 

14.6674 -160 0 

1037.512 -10 0 

7.7411 -190 0 

0.2037 -390 0 

0.4074 -410 0 

25.0567 -140 0 
A-17 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

1.0186 -280 0 

0.4074 -380 0 

0.2037 -530 0 

0.2037 -830 0 

5.9077 -200 0 

1.6297 -240 0 

0.6111 -320 0 

94.1156 -80 0 

33.409 -120 0 

1.0186 -260 0 

0.2037 -490 0 

0.2037 -300 0 

0.4074 -340 0 

0.2037 -550 0 

0.2037 -400 0 

658.8089 -30 -10 

320.2374 -50 -10 

87.5967 -70 -10 

35.8535 -90 -10 

11.4079 -110 -10 

8.1485 -130 -10 

4.0743 -150 -10 

1.6297 -170 -10 

1.0186 -190 -10 

0.8149 -210 -10 

0.4074 -230 -10 

0.4074 -270 -10 

418.4272 -40 -20 

130.1728 -60 -20 

54.3915 -80 -20 

25.4642 -100 -20 

9.7782 -120 -20 

5.5003 -140 -20 

2.2408 -160 -20 

2.0371 -180 -20 

0.4074 -200 -20 

0.2037 -220 -20 
A-18 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

0.2037 -260 -20

0.4074 -280 -20

0.2037 -300 -20

0.8149 -500 -20

322.0708 -50 -30

133.0248 -70 -30

32.1867 -90 -30

9.982 -110 -30

3.6668 -130 -30

2.6483 -150 -30

0.4074 -170 -30

0.6111 -190 -30

0.2037 -210 -30

0.2037 -230 -30

0.2037 -250 -30

0.2037 -290 -30

0.2037 -450 -30

277.4576 -60 -40

81.4853 -80 -40

31.1681 -100 -40

13.2414 -120 -40

6.3151 -140 -40

1.6297 -160 -40

1.6297 -180 -40

0.4074 -200 -40

0.6111 -220 -40

0.8149 -240 -40

0.2037 -300 -40

0.4074 -500 -40

142.1919 -70 -50

68.6514 -90 -50

10.7968 -110 -50

6.7225 -130 -50

2.6483 -150 -50

1.0186 -170 -50

0.2037 -190 -50

0.4074 -210 -50
A-19 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

0.2037 -230 -50 

0.6111 -250 -50 

179.2677 -80 -60 

40.3352 -100 -60 

15.4822 -120 -60 

4.6854 -140 -60 

2.2408 -160 -60 

0.4074 -180 -60 

0.4074 -200 -60 

0.2037 -220 -60 

0.2037 -240 -60 

0.2037 -260 -60 

0.2037 -280 -60 

0.2037 -300 -60 

0.2037 -340 -60 

0.2037 -360 -60 

0.2037 -380 -60 

0.2037 -500 -60 

76.1888 -90 -70 

35.0387 -110 -70 

7.5374 -130 -70 

2.852 -150 -70 

1.2223 -170 -70 

0.6111 -190 -70 

0.2037 -210 -70 

0.4074 -230 -70 

0.2037 -290 -70 

102.2641 -100 -80 

23.8345 -120 -80 

4.278 -140 -80 

2.4446 -160 -80 

0.4074 -180 -80 

0.4074 -200 -80 

0.2037 -220 -80 

0.6111 -240 -80 

0.2037 -260 -80 

0.4074 -280 -80 

0.2037 -360 -80 
A-20 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

29.7421 -110 -90

14.8711 -130 -90

2.852 -150 -90

2.4446 -170 -90

1.0186 -190 -90

0.2037 -210 -90

0.2037 -230 -90

0.4074 -250 -90

41.5575 -120 -100

8.9634 -140 -100

2.0371 -160 -100

0.8149 -180 -100

0.2037 -200 -100

0.4074 -220 -100

0.2037 -260 -100

0.2037 -280 -100

0.2037 -320 -100

0.2037 -340 -100

11.8154 -130 -110

4.8891 -150 -110

2.2408 -170 -110

0.4074 -190 -110

0.2037 -210 -110

0.4074 -230 -110

0.2037 -250 -110

0.2037 -270 -110

0.2037 -310 -110

13.2414 -140 -120

3.2594 -160 -120

1.426 -180 -120

0.4074 -200 -120

1.0186 -240 -120

0.6111 -260 -120

0.4074 -280 -120

0.6111 -300 -120

0.2037 -320 -120
A-21 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

7.13 -150 -130

3.8706 -170 -130

0.2037 -190 -130

0.6111 -210 -130

0.2037 -250 -130

0.4074 -270 -130

0.2037 -290 -130

0.2037 -370 -130

6.9263 -160 -140

2.0371 -180 -140

0.8149 -200 -140

0.6111 -220 -140

0.2037 -240 -140

0.4074 -260 -140

0.6111 -280 -140

0.2037 -320 -140

0.2037 -500 -140

4.0743 -170 -150

1.0186 -190 -150

0.8149 -210 -150

0.4074 -230 -150

0.2037 -250 -150

0.2037 -290 -150

0.4074 -310 -150

4.6854 -180 -160

1.426 -200 -160

0.4074 -220 -160

0.6111 -240 -160

0.4074 -260 -160

0.4074 -280 -160

0.4074 -300 -160

0.2037 -380 -160

0.2037 -500 -160

1.2223 -190 -170

1.426 -210 -170

0.6111 -230 -170

0.2037 -250 -170

3.4631 -200 -180
A-22 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

1.426 -220 -180 

0.4074 -260 -180 

0.4074 -280 -180 

0.2037 -300 -180 

0.2037 -320 -180 

0.2037 -420 -180 

1.426 -210 -190 

1.2223 -230 -190 

1.2223 -250 -190 

0.2037 -370 -190 

0.2037 -430 -190 

3.4631 -220 -200 

0.8149 -240 -200 

0.6111 -260 -200 

0.4074 -340 -200 

0.8149 -230 -210 

0.6111 -250 -210 

0.4074 -270 -210 

0.2037 -310 -210 

0.4074 -350 -210 

3.2594 -240 -220 

1.0186 -260 -220 

0.2037 -280 -220 

0.2037 -320 -220 

0.2037 -340 -220 

0.2037 -250 -230 

0.6111 -270 -230 

0.4074 -290 -230 

2.0371 -260 -240 

0.6111 -280 -240 

0.2037 -300 -240 

0.2037 -320 -240 

0.2037 -400 -240 

0.2037 -420 -240 

1.6297 -280 -260 

0.8149 -300 -260 

0.4074 -320 -260 

0.2037 -340 -260 
A-23 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

0.2037 -380 -260 

0.2037 -290 -270 

0.2037 -370 -270 

1.6297 -300 -280 

0.8149 -320 -280 

0.2037 -360 -280 

0.2037 -380 -280 

0.6111 -310 -290 

0.6111 -320 -300 

0.6111 -340 -300 

0.2037 -360 -300 

0.2037 -330 -310 

0.2037 -350 -310 

0.2037 -340 -320 

0.4074 -360 -320 

0.2037 -380 -320 

0.4074 -400 -320 

0.2037 -390 -330 

1.0186 -360 -340 

0.2037 -380 -340 

0.2037 -400 -340 

0.2037 -420 -340 

0.4074 -380 -360 

0.2037 -400 -360 

0.2037 -420 -360 

0.2037 -440 -360 

0.4074 -400 -380 

0.4074 -420 -380 

0.2037 -460 -380 

0.2037 -420 -400 

0.4074 -500 -400 

0.2037 -440 -420 

0.2037 -460 -440 

0.2037 -480 -440 

0.4074 -480 -460 

0.6111 -500 -460 

0.2037 -500 -480 
A-24 

A-IV. Unloaded Tank LCF Buff Events 

Unloaded 100-Ton Tank Car Longitudinal Buff Coupler Force 

10,000-Mile Scaled DTA Load Schedule 

Negative = Buff Loading Unloaded/Loaded Ratio = 1.06 

LCF—ULBUF 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

1.8779 -340 0 

5.0077 -270 0 

1.2519 -450 0 

10.0153 -160 0 

4.3817 -180 0 

2.5038 -310 0 

35.0536 -120 0 

2.5038 -220 0 

9.3894 -190 0 

11.8932 -210 0 

10.6413 -230 0 

0.626 -590 0

0.626 -650 0

3.7557 -290 0 

2.5038 -350 0 

1.2519 -430 0 

14.397 -140 0 

0.626 -400 0

173.3903 -70 0 

95.1456 -90 0 

50.0766 -130 0 

31.2979 -150 0 

18.1528 -170 0 

5.6336 -250 0 

3.1298 -390 0 

307.3453 -20 0 

169.0086 -40 0 

107.6648 -60 0 

71.9852 -80 0 

56.3362 -100 0 

0.626 -200 0

0.626 -260 0

301.7117 -50 0 

59.466 -110 0 
A-25 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

878.8449 -10 0 

1.2519 -370 0 

1.8779 -410 0 

650.3703 -30 0 

3.1298 -330 0 

0.626 -320 0 

0.626 -630 0 

0.626 -240 0 

1.2519 -280 0 

1086.6628 -30 -10 

592.7821 -50 -10 

148.978 -70 -10 

66.3515 -90 -10 

30.6719 -110 -10 

11.8932 -130 -10 

6.2596 -150 -10 

3.1298 -170 -10 

6.2596 -190 -10 

3.1298 -210 -10 

1.8779 -230 -10 

0.626 -250 -10 

0.626 -290 -10 

440.0484 -40 -20 

134.581 -60 -20 

58.84 -80 -20 

23.7864 -100 -20 

8.1375 -120 -20 

0.626 -140 -20 

1.2519 -160 -20 

0.626 -180 -20 

513.2855 -50 -30 

224.7189 -70 -30 

63.2217 -90 -30 

11.2672 -110 -30 

10.0153 -130 -30 

5.6336 -150 -30 

1.8779 -170 -30 
A-26 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

1.2519 -190 -30 

1.2519 -210 -30 

0.626 -230 -30 

0.626 -250 -30 

0.626 -270 -30 

0.626 -430 -30 

299.8338 -60 -40 

67.6035 -80 -40 

16.9009 -100 -40 

8.1375 -120 -40 

0.626 -140 -40 

0.626 -180 -40 

0.626 -200 -40 

0.626 -220 -40 

214.7036 -70 -50 

105.1609 -90 -50 

19.4047 -110 -50 

12.5192 -130 -50 

2.5038 -150 -50 

3.1298 -170 -50 

3.1298 -190 -50 

0.626 -210 -50 

0.626 -230 -50 

0.626 -250 -50 

0.626 -330 -50 

0.626 -590 -50 

102.0311 -80 -60 

26.9162 -100 -60 

5.6336 -120 -60 

3.1298 -140 -60 

0.626 -160 -60 

0.626 -180 -60 

0.626 -200 -60 

60.092 -90 -70 

43.8171 -110 -70 

25.6643 -130 -70 

1.2519 -150 -70 

0.626 -170 -70 
A-27 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

1.2519 -190 -70 

0.626 -210 -70 

0.626 -290 -70 

63.2217 -100 -80 

12.5192 -120 -80 

1.8779 -140 -80 

1.2519 -160 -80 

0.626 -180 -80 

0.626 -200 -80 

0.626 -220 -80 

0.626 -280 -80 

0.626 -320 -80 

43.8171 -110 -90 

32.5498 -130 -90 

4.3817 -150 -90 

2.5038 -170 -90 

1.8779 -190 -90 

1.2519 -210 -90 

38.8094 -120 -100 

6.8855 -140 -100 

1.2519 -160 -100 

1.2519 -180 -100 

0.626 -280 -100 

21.2826 -130 -110 

10.0153 -150 -110 

0.626 -190 -110 

0.626 -210 -110 

1.8779 -230 -110 

0.626 -310 -110 

4.3817 -140 -120 

0.626 -160 -120 

1.2519 -180 -120 

1.2519 -200 -120 

1.2519 -260 -120 

5.6336 -150 -130 

5.6336 -170 -130 

1.8779 -190 -130 

1.2519 -210 -130 
A-28 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

1.2519 -230 -130 

0.626 -250 -130 

0.626 -350 -130 

2.5038 -160 -140 

1.2519 -180 -140 

0.626 -200 -140 

1.2519 -220 -140 

0.626 -260 -140 

0.626 -300 -140 

0.626 -320 -140 

3.1298 -170 -150 

3.7557 -190 -150 

1.2519 -210 -150 

1.2519 -230 -150 

0.626 -250 -150 

1.2519 -180 -160 

0.626 -200 -160 

0.626 -260 -160 

0.626 -280 -160 

2.5038 -190 -170 

5.6336 -210 -170 

0.626 -230 -170 

0.626 -270 -170 

0.626 -290 -170 

0.626 -310 -170 

0.626 -370 -170 

5.0077 -200 -180 

1.2519 -220 -180 

3.7557 -210 -190 

2.5038 -230 -190 

0.626 -250 -190 

1.2519 -270 -190 

0.626 -290 -190 

1.2519 -310 -190 

1.8779 -220 -200 

1.2519 -240 -200 

1.2519 -260 -200 

0.626 -300 -200 
A-29 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

1.2519 -230 -210 

1.2519 -250 -210 

0.626 -310 -210 

0.626 -350 -210 

1.2519 -240 -220 

0.626 -400 -220 

0.626 -250 -230 

1.2519 -270 -230 

0.626 -290 -230 

0.626 -330 -230 

0.626 -410 -230 

0.626 -260 -240 

0.626 -280 -240 

1.2519 -270 -250 

0.626 -290 -250 

1.2519 -330 -250 

0.626 -450 -250 

0.626 -280 -260 

1.2519 -300 -260 

1.2519 -290 -270 

0.626 -310 -270 

1.2519 -350 -270 

0.626 -390 -270 

1.8779 -300 -280 

0.626 -320 -280 

0.626 -340 -280 

0.626 -320 -300 

0.626 -330 -310 

0.626 -350 -310 

0.626 -340 -320 

0.626 -380 -320 

0.626 -390 -330 

0.626 -370 -350 

1.2519 -380 -360 

0.626 -400 -380 
A-30 

A-V. Loaded Tank LCF Draft Events 

Loaded 100-Ton Tank Car Longitudinal Draft Coupler Force 

10,000-Mile Scaled DTA Load Schedule 

Positive = Draft Loading Unloaded/Loaded Ratio = 1.06 

LCF—LLDFT 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

0.2037 0 410

0.2037 350 390

0.4074 350 370

0.2037 0 370

0.2037 330 350

0.2037 250 350

1.0186 0 350

0.8149 310 330

1.426 290 330

0.4074 270 330

0.6111 250 330

0.6111 230 330

0.2037 210 330

0.2037 150 330

0.2037 110 330

1.6297 0 330

3.6668 290 310

5.0928 270 310

1.0186 250 310

0.2037 230 310

0.8149 210 310

0.2037 190 310

0.2037 150 310

0.2037 130 310

0.2037 110 310

0.2037 0 310

12.0191 280 300

5.0928 260 300

2.4446 240 300

0.2037 220 300

0.4074 200 300

0.2037 180 300

0.6111 160 300
A-31 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

0.2037 100 300 

0.8149 80 300 

1.0186 60 300 

2.6483 40 300 

2.2408 20 300 

14.8711 0 300 

5.2965 270 290 

7.13 250 290 

4.278 230 290 

1.0186 210 290 

0.6111 170 290 

0.4074 150 290 

0.2037 130 290 

0.4074 110 290 

0.2037 30 290 

2.0371 0 290 

7.13 260 280 

2.2408 240 280 

0.8149 220 280 

0.2037 200 280 

0.2037 140 280 

0.2037 60 280 

0.4074 40 280 

0.2037 20 280 

1.0186 0 280 

22.6122 250 270 

14.4636 230 270 

5.5003 210 270 

3.0557 190 270 

1.0186 170 270 

0.8149 150 270 

0.4074 130 270 

1.2223 110 270 

0.4074 30 270 

0.6111 10 270 

3.8706 0 270 

4.4817 240 260 
A-32 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

1.8334 220 260 

0.6111 200 260 

0.6111 180 260 

0.2037 140 260 

0.2037 120 260 

0.2037 80 260 

0.2037 60 260 

0.2037 40 260 

1.2223 0 260 

33.0016 230 250 

36.6684 210 250 

9.982 190 250 

4.4817 170 250 

1.426 150 250 

1.6297 130 250 

2.4446 110 250 

0.8149 90 250 

0.2037 70 250 

0.6111 50 250 

0.6111 30 250 

1.0186 10 250 

6.1114 0 250 

5.704 220 240 

1.0186 200 240 

0.8149 180 240 

0.2037 120 240 

0.2037 100 240 

0.4074 60 240 

0.6111 40 240 

0.4074 20 240 

2.2408 0 240 

56.2249 210 230 

51.7432 190 230 

18.7416 170 230 

6.5188 150 230 

4.0743 130 230 

7.3337 110 230 
A-33 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

2.4446 90 230 

1.6297 70 230 

1.6297 50 230 

0.8149 30 230 

0.8149 10 230 

6.7225 0 230 

8.1485 200 220 

2.0371 180 220 

1.2223 160 220 

0.2037 140 220 

0.4074 100 220 

0.8149 60 220 

0.2037 40 220 

0.4074 20 220 

4.4817 0 220 

147.2847 190 210 

110.4126 170 210 

34.0201 150 210 

13.6488 130 210 

13.6488 110 210 

4.4817 90 210 

2.6483 70 210 

3.6668 50 210 

4.278 30 210 

1.2223 10 210 

8.3522 0 210 

9.5745 180 200 

4.4817 160 200 

1.8334 140 200 

0.2037 120 200 

0.8149 100 200 

0.6111 80 200 

0.4074 60 200 

0.2037 40 200 

0.4074 20 200 

7.7411 0 200 

283.9764 170 190 
A-34 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

254.438 150 190 

60.0954 130 190 

28.9273 110 190 

11.0005 90 190 

5.2965 70 190 

4.0743 50 190 

4.278 30 190 

3.0557 10 190 

13.6488 0 190 

15.6859 160 180 

1.6297 140 180 

2.2408 120 180 

0.8149 100 180 

1.0186 80 180 

1.0186 60 180 

0.6111 40 180 

1.2223 20 180 

11.0005 0 180 

673.0689 150 170 

549.2112 130 170 

88.2079 110 170 

16.5008 90 170 

6.1114 70 170 

6.3151 50 170 

3.6668 30 170 

4.8891 10 170 

13.4451 0 170 

22.6122 140 160 

6.1114 120 160 

2.6483 100 160 

3.0557 80 160 

1.2223 60 160 

1.8334 40 160 

1.426 20 160 

19.5565 0 160 

1309.0619 130 150 

495.0234 110 150 
A-35 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

51.3358 90 150 

10.3894 70 150 

7.5374 50 150 

8.7597 30 150 

5.5003 10 150 

24.0382 0 150 

49.5023 120 140 

16.5008 100 140 

6.9263 80 140 

5.0928 60 140 

4.6854 40 140 

0.8149 20 140 

26.4827 0 140 

810.3717 110 130 

217.1584 90 130 

36.0573 70 130 

15.4822 50 130 

16.0934 30 130 

11.6117 10 130 

28.9273 0 130 

62.54 100 120 

17.5193 80 120 

10.1857 60 120 

10.7968 40 120 

4.4817 20 120 

37.2795 0 120 

321.2559 90 110 

187.2126 70 110 

44.6132 50 110 

31.7793 30 110 

24.2419 10 110 

49.7061 0 110 

119.376 80 100 

41.9649 60 100 

28.3162 40 100 

16.0934 20 100 

74.3554 0 100 
A-36 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

382.3699 70 90 

234.0666 50 90 

87.5967 30 90 

55.2063 10 90 

90.4487 0 90 

246.4931 60 80 

81.0779 40 80 

54.5952 20 80 

124.0614 0 80 

698.3293 50 70 

551.6557 30 70 

190.472 10 70 

163.3781 0 70 

583.8424 40 60 

170.1006 20 60 

197.8057 0 60 

2044.467 30 50 

1281.7643 10 50 

209.4173 0 50 

2134.7122 20 40 

349.9795 0 40 

2415.8364 10 30 

482.5969 0 30 

1925.7021 0 20 

864.3557 0 10 
A-37 

A-VI. Unloaded Tank LCF Draft Events 

Unloaded 100-Ton Tank Car Longitudinal Draft Coupler Force 

10,000-Mile Scaled DTA Load Schedule 

Positive = Draft Loading Unloaded/Loaded Ratio = 1.06 

LCF—ULDFT 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

1.2519 280 300 

0.626 0 300 

1.2519 0 270 

1.2519 220 260 

0.626 180 260 

1.2519 0 260 

0.626 0 250 

2.5038 220 240 

0.626 60 240 

0.626 20 240 

1.2519 0 240 

3.7557 210 230 

1.8779 190 230 

0.626 170 230 

0.626 90 230 

0.626 10 230 

4.3817 0 230 

5.6336 200 220 

0.626 120 220 

0.626 0 220 

5.0077 190 210 

0.626 110 210 

1.2519 10 210 

4.3817 0 210 

6.8855 180 200 

3.7557 160 200 

1.8779 140 200 

1.2519 80 200 

3.1298 0 200 

2.5038 170 190 

1.8779 150 190 

0.626 130 190 

2.5038 110 190 
A-38 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

1.2519 90 190

1.8779 70 190

0.626 50 190

0.626 30 190

1.2519 10 190

10.0153 0 190

14.397 160 180

3.1298 140 180

1.2519 120 180

0.626 100 180

0.626 40 180

1.2519 20 180

11.8932 0 180

18.1528 150 170

6.8855 130 170

3.1298 110 170

2.5038 90 170

0.626 70 170

1.2519 50 170

1.8779 30 170

2.5038 10 170

10.0153 0 170

15.023 140 160

5.0077 120 160

1.8779 100 160

1.2519 80 160

1.8779 60 160

0.626 40 160

0.626 20 160

15.023 0 160

17.5268 130 150

23.7864 110 150

10.0153 90 150

3.1298 70 150

1.8779 50 150

2.5038 30 150

5.0077 10 150

25.6643 0 150
A-39 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

22.5345 120 140

11.2672 100 140

7.5115 80 140

3.7557 60 140

5.0077 40 140

1.2519 20 140

23.1604 0 140

78.8707 110 130

62.5958 90 130

20.0307 70 130

18.7787 50 130

13.7711 30 130

10.0153 10 130

38.8094 0 130

51.3285 100 120

20.6566 80 120

13.1451 60 120

6.8855 40 120

9.3894 20 120

36.3056 0 120

160.2452 90 110

159.6193 70 110

61.3439 50 110

38.1834 30 110

27.5421 10 110

60.7179 0 110

142.0924 80 100

52.5805 60 100

35.6796 40 100

19.4047 20 100

58.2141 0 100

349.2845 70 90

251.0091 50 90

99.5273 30 90

77.6188 10 90

92.0158 0 90

445.682 60 80

142.0924 40 80
A-40 

Fractional Cycle Count Minimum Load (kips) Maximum Load (kips) 

60.092 20 80 

103.2831 0 80 

959.5935 50 70 

575.2553 30 70 

243.4976 10 70 

142.0924 0 70 

1206.2209 40 60 

184.0316 20 60 

155.2376 0 60 

2242.1812 30 50 

1484.7722 10 50 

194.047 0 50 

1039.7161 20 40 

233.4823 0 40 

1671.3076 10 30 

299.8338 0 30 

492.0029 0 20 

1439.7032 0 10 
B-1 

Appendix B. 

Full-Scale Damage Tolerance Test Crack Indication Log 

B-I. B-End Left Crack Indications 

B-End Left Critical Region Crack Lengths 

All Measurements in Inches

Spectrum A B H I J S V Z AA AC 

Miles (BL) (BL) (BL) (BL) (BL) (BL) (BL) (BL) (BL) (BL) 

preflaw preflaw 

 

0 (after precrack) 0.14? 0.14? 

10,000 0.14? 0.14? >> 3.35* 

20,000 0.14? 0.14? 2.25* 1.50 

30,000 0.14? 0.14? 2.25* 1.50 

40,000 0.14? 0.14? 2.26* 1.50 

50,000 0.14? 0.14? 2.28* 1.50 

60,000 0.14? 0.14? 2.28* 1.50 

70,000 0.14? 0.14? 2.28* 1.50 

80,000 

100,000 -- -- 2.25* 1.46 

120,000 -- -- 1.48 

140,000 -- -- 1.48 0.20? 

160,000 -- -- 1.51 -- 

180,000 -- -- 1.52 0.20? 2.23? 

200,000 -- -- 1.52 -- 2.23? 

200,000 -- -- 2.25* 1.59 0.39 -- 2.23? 

210,000 -- -- 1.59 0.39 -- 2.23? 0.22 

220,000 -- -- 1.61 0.39 -- 2.83?~ 0.24 

230,000 -- -- 1.61 0.39 -- 2.83? 0.31 0.20 

240,000 -- -- 1.61 0.39 -- 2.83? 0.31 -- 

250,000 -- -- 1.61 0.39 -- 2.83? 0.34 -- 

260,000 -- -- 1.61 0.39 -- 2.83? 0.34 -- 0.13 

270,000 -- -- 1.61 0.39 -- 2.83? 0.34 -- 0.20 

280,000 -- -- 1.61 0.39 -- 2.83? 0.41 -- 0.20 

290,000 -- -- 1.61 0.39 -- 2.83? 0.41 -- 0.20 

300,000 -- -- 1.61 0.39 -- 2.83? 0.43 -- 0.23 

300,000 x x 2.30 1.61 0.35 0.16 2.75+ 0.33 0.30 0.29 
B-2 

Legend 

? not certain crack exists (typically in weld toe) 

* unpolished for measurement (when first found) 

-- penetrant did not pick up (measurement attempted) 

>> combined measurement (with adjacent crack) 

~ new reference mark (after a test hiatus) 

(blank) no measurement was made 

x no crack was discernable 

( ) measurement was approximated 

+ crack extends beyond measurement 

Notes 

- many cracks in weld toes, not certain of existence 

- uncertainty varies from +/- 0.01 to 0.05 inches, depending on location 

- no preload on inspection after 70,000 simulated miles 

- 3-month hiatus after 200,000 miles 

- second inspection at 300,000 miles with fiber scope and preload 

- cracks suspected from preflaws denoted by preflaw at top 

- cracks opened up for fractographic analysis denoted by fracto at top 
B-3 

B-II. B-End Right Crack Indications 

B-End Right Critical Region Crack Lengths 

All Measurements in Inches

Spectrum P Q W X Y AD 

Miles (BR) (BR) (BR) (BR) (BR) (BR) 

 

 

0 (after precrack) 

10,000 

20,000 

30,000 

40,000 

50,000 

60,000 

70,000 

80,000 

100,000 

120,000 1.00?* 

140,000 1.50?* 

160,000 1.50?* 

180,000 1.50?* 1.50? 1.30? 

200,000 1.50?* 1.50? 1.30? 

200,000 1.85?*~ 0.12* 

210,000 0.14 1.93?~ 1.32?~ 0.12* 

220,000 0.14 1.93? 1.32? 0.12* 

230,000 0.20 1.93? 1.32? 0.12* 

240,000 1.93? 1.32? 0.12* 

250,000 1.93? 1.32? 0.23?* 

260,000 1.93? 1.39? 0.23?* 0.20 

270,000 1.93? 1.39? 0.23?* 0.20 

280,000 1.93? 1.39? 0.23?* 0.45 

290,000 1.93? 1.39? 1.05?* 0.60 

300,000 1.95? 1.39? 1.10?* 0.61 

300,000 x 0.18 x 1.11 x 0.38 
B-4 

Legend 

? not certain crack exists (typically in weld toe) 

* unpolished for measurement (when first found) 

-- penetrant did not pick up (measurement attempted) 

>> combined measurement (with adjacent crack) 

~ new reference mark (after a test hiatus) 

(blank) no measurement was made 

x no crack was discernable 

( ) measurement was approximated 

+ crack extends beyond measurement 

Notes 

- many cracks in weld toes, not certain of existence 

- uncertainty varies from +/- 0.01 to 0.05 inches, depending on location 

- no preload on inspection after 70,000 simulated miles 

- 3-month hiatus after 200,000 miles 

- second inspection at 300,000 miles with fiber scope and preload 

- cracks suspected from preflaws denoted by preflaw at top 

- cracks opened up for fractographic analysis denoted by fracto at top 
B-5 

B-III. A-End Left Crack Indications 

A-End Left Critical Region Crack Lengths 

All Measurements in Inches

Spectrum C D E F K L M R 

Miles (AL) (AL) (AL) (AL) (AL) (AL) (AL) (AL) 

Preflaw preflaw 

 fracto fracto fracto 

0 (after precrack) 0.35* 0.16 1.30* << 

10,000 0.36* 0.17 1.20* << >> 1.35* 2.95?* 

20,000 0.28 0.17 1.08 << >> 1.25 2.90?* 

30,000 0.30 0.22 1.07 << >> 1.28 3.00?* 

40,000 0.30 0.22 1.07 << >> 1.29 3.00?* 

50,000 0.30 0.22 1.07 << >> 1.29 3.00?* 

60,000 0.30 0.22 1.07 << >> 1.29 3.00?* 

70,000 0.30 0.22 1.07 << >> 1.32 3.08?* 

80,000 0.23 0.18 0.98 0.87?* >> 1.85 1.00?* 

100,000 0.27 0.20 1.04 3.17?* >> 1.21 1.00?* 

120,000 0.27 0.21 -- -- >> 1.33 1.00?* 0.11* 

140,000 0.27 0.21 1.04 3.42?* 0.10 1.28 1.00?* 0.14 

160,000 0.35 0.21 1.04 -- 0.10 1.28 1.00?* 0.14 

180,000 0.35 0.21 1.04 3.42?* 0.10 1.28 1.00?* 0.14 

200,000 0.35 0.21 1.04 -- 0.10 1.28 -- 0.14 

200,000 0.35 0.21 1.07 -- 0.10 1.28 0.14 

210,000 0.35 0.21 1.07 -- 0.10 1.28 0.14 

220,000 0.35 -- 1.07 -- -- 1.28 0.14 

230,000 0.35 0.21 1.07 3.99?*~ -- 1.28 0.19 

240,000 0.35 0.21 1.07 3.99?* -- 1.28 0.19 

250,000 0.35 0.21 1.07 3.99?* -- 1.28 0.19 

260,000 0.38 0.21 1.07 3.99?* -- 1.28 0.27 

270,000 0.38 0.21 1.07 3.99?* -- 1.28 0.30 

280,000 0.38 0.21 1.07 3.99?* -- 1.28 0.31 

290,000 0.38 0.21 1.07 4.39?* -- 1.28 0.34 

300,000 0.38 0.21 1.07 4.39?* -- 1.28 0.36 

300,000 0.37 0.23 1.05 1.70 0.15 1.32 (5-3/8) 0.31 
B-6 

Legend 

? not certain crack exists (typically in weld toe) 

* unpolished for measurement (when first found) 

-- penetrant did not pick up (measurement attempted) 

>> combined measurement (with adjacent crack) 

~ new reference mark (after a test hiatus) 

(blank) no measurement was made 

X no crack was discernable 

( ) measurement was approximated 

+ crack extends beyond measurement 

Notes 

- many cracks in weld toes, not certain of existence 

- uncertainty varies from +/- 0.01 to 0.05 inches, depending on location 

- no preload on inspection after 70,000 simulated miles 

- 3-month hiatus after 200,000 miles 

- second inspection at 300,000 miles with fiber scope and preload 

- cracks suspected from preflaws denoted by preflaw at top 

- cracks opened up for fractographic analysis denoted by fracto at top 
B-7 

B-IV. A-End Right Crack Indications 

A-End Right Critical Region Crack Lengths 

All Measurements in Inches

Spectrum G N O T U AB 

Miles (AR) (AR) (AR) (AR) (AR) (AR) 

preflaw 

 

0 (after precrack) 0.12 

10,000 0.12 

20,000 0.13 0.63 0.34* 

30,000 0.13 0.41 

40,000 0.13 0.41 

50,000 0.13 0.42 

60,000 0.13 0.42 

70,000 0.13 0.44 

80,000 

100,000 -- 0.46 

120,000 -- 0.52 

140,000 -- 0.52 

160,000 -- 0.52 

180,000 -- 0.52 2.09?* 0.97?*

200,000 -- 0.52 2.09? 0.97?

200,000 -- 0.52 1.75?~ 1.50?~

210,000 -- 0.56 1.75? 1.50?

220,000 -- 0.61 1.84? 1.50?

230,000 -- 0.65 1.84? 1.50? 0.34

240,000 -- 0.65 1.84? 1.50? 0.34

250,000 -- 0.67 1.84? 1.50? 0.34

260,000 -- 0.69 1.87? 1.52? 0.34

270,000 -- 0.69 1.87? 1.52? 0.34

280,000 -- 0.72 1.87? 1.52? 0.34

290,000 -- 0.74 1.87? 1.52? 0.34

300,000 -- 0.75 1.87? 1.52? 0.34

300,000 0.12 0.63 0.78 (3-3/8) x 0.28
B-8 

Legend 

? not certain crack exists (typically in weld toe) 

* unpolished for measurement (when first found) 

-- penetrant did not pick up (measurement attempted) 

>> combined measurement (with adjacent crack) 

~ new reference mark (after a test hiatus) 

(blank) no measurement was made 

X no crack was discernable 

( ) measurement was approximated 

+ crack extends beyond measurement 

Notes 

- many cracks in weld toes, not certain of existence 

- uncertainty varies from +/- 0.01 to 0.05 inches, depending on location 

- no preload on inspection after 70,000 simulated miles 

- 3-month hiatus after 200,000 miles 

- second inspection at 300,000 miles with fiber scope and preload 

- cracks suspected from preflaws denoted by preflaw at top 

- cracks opened up for fractographic analysis denoted by fracto at top 
C-1 

Appendix C. 

Piecewise Carbody Compliance Test Data 

C-I. Vertical Sill Deflections 
C-2 
C-3 
C-4 
C-5 
C-6 
C-7 
C-8 
C-9 
C-10 

C-II. B-End Sill Bending Stresses 
C-11 
C-12 
C-13 
C-14 
C-15 
C-16 
C-17 
C-18 
C-19 

C-III. A-End Sill Bending Stresses 
C-20 
C-21 
C-22 
C-23 
C-24 
C-25 
C-26 
C-27 
C-28 

C-IV. Vertical Head Stresses (BL, BR, and AL) 
C-29 
C-30 
C-31 
C-32 
C-33 
C-34 
C-35 
C-36 
C-37 

C-V. Von Mises Head Stresses (AL, BL, and BR) 
C-38 
C-39 
C-40 
C-41 
C-42 
C-43 
C-44 
C-45 
C-46 

C-VI. Vertical Web Stresses (BL and AL) 
C-47 
C-48 
C-49 
C-50 
C-51 
C-52 
C-53 
C-54 
C-55 

C-VIII. A-End Left Von Mises Web Stress 
C-56 
C-57 
C-58 
C-59 
C-60 
C-61 
C-62 
C-63 
C-64 

C-VIII. B-End Right Longitudinal Flange Stresses 
C-65 
C-66 
C-67 
C-68 
C-69 
C-70 
C-71 
C-72 
C-73 

C-IX. A-End Right Longitudinal Flange Stresses 
C-74 
C-75 
C-76 
C-77 
C-78 
C-79 
C-80 
C-81 
C-82 
D-1 

Appendix D. 

Carbody Compliance Sensitivities 

D-I. LCF Buff Compliance Peaks 

Critical Region Compliance to 500 kips LCF Buff 

Strain Data 

 (Test 1) (Test 2) (Test 3) (Test 4) (Test 5) (Test 6) (Test 7) (Test 8) (Test 9) 

Mileage 0 0 50,000 100,000 150,000 200,000 200,000 250,000 300,000 spec mi 

LCF_D 0 0 0 0 0 0 0 0 0 kip 

LCF -502 -503 -499 -503 -500 -502 -501 -501 -500 kip 

VCFE_D 0 0 0 1 0 0 0 0 0 kip 

VCFE 0 0 0 0 0 0 -1 0 0 kip 

VCFW_D 0 0 0 0 0 0 0 0 0 kip 

VCFW 0 0 0 0 0 0 -1 2 0 kip 

SPE 0.00 -0.17 -0.15 -0.16 -0.15 -0.13 -0.14 -0.16 -0.17 in 

VCDE -0.18 -0.14 -0.16 -0.15 -0.14 -0.17 -0.14 -0.15 -0.16 in 

SPW 0.00 -0.14 -0.13 -0.17 -0.15 -0.10 -0.14 -0.15 -0.14 in 

VCDW -0.17 -0.19 -0.20 -0.20 -0.20 -0.18 -0.18 -0.18 -0.20 in 

BLH1 692 636 650 587 441 334 555 609 651 ustr 

BLH2 171 153 163 119 125 158 115 156 185 ustr 

BLH3 -66 26 46 35 38 52 42 78 88 ustr 

BLHp1 21.7 21.3 22.0 20.1 14.8 11.0 19.1 21.1 22.4 ksi 

BLHp2 3.3 5.2 5.8 4.8 4.3 4.4 4.8 6.4 7.1 ksi 

BLHang -10 -15 -16 -17 -15 -7 -18 -18 -17 deg 

BLHvM 20.3 19.2 19.7 18.2 13.2 9.6 17.2 18.8 19.8 ksi 

BLH4 459 381 388 357 359 394 341 362 392 ustr 

BLW1 314 258 178 148 210 100 153 209 196 ustr 

BLW2 406 316 226 185 261 90 177 228 207 ustr 

BLW3 192 151 101 95 89 135 81 85 101 ustr 

BLW4 253 208 160 151 143 196 128 133 148 ustr 

BRH1 -6 -38 6 -5 -14 -11 -15 9 5 ustr 

BRH2 326 237 303 271 260 300 243 293 318 ustr 

BRH3 771 639 724 682 689 728 624 714 774 ustr 

BRHp1 24.2 19.8 22.9 21.5 21.7 22.8 19.6 22.6 24.5 ksi 

BRHp2 6.4 4.2 6.3 5.6 5.3 5.8 4.8 6.3 6.7 ksi 

BRHang 4 5 5 6 6 4 5 5 5 deg 

BRHvM 21.8 18.1 20.5 19.3 19.6 20.6 17.7 20.2 21.9 ksi 

BRH4 469 396 427 402 407 446 384 416 453 ustr 

BRF1 -415 -517 -442 -459 -494 -479 -435 -441 -486 ustr 
D-2 

BRF2 -427 -806 144 1837 0 0 0 0 0 ustr 

BRF3 -663 -766 -621 -636 -712 -687 -613 -641 -711 ustr 

BRF4 -617 -335 -204 -638 -703 -679 -600 -624 -698 ustr 

ALH1 -202 79 202 212 226 175 294 213 235 ustr 

ALH2 507 402 393 339 313 200 198 191 143 ustr 

ALH3 -13 -174 -180 -206 -221 -227 -214 -257 -250 ustr 

ALHp1 9.8 8.7 10.2 9.1 8.8 5.8 8.4 6.3 6.2 ksi 

ALHp2 -18.4 -12.5 -9.3 -8.9 -8.6 -7.9 -5.2 -8.1 -6.8 ksi 

ALHang -41 37 32 29 27 24 16 21 16 deg 

ALHvM 24.8 18.5 16.8 15.6 15.1 12.0 11.9 12.5 11.2 ksi 

ALH4 332 246 219 195 185 166 134 144 149 ustr 

ALW1 -257 -453 -392 -411 -416 -347 -287 -445 -408 ustr 

ALW2 -516 -475 -419 -440 -446 -354 -313 -466 -410 ustr 

ALW3 120 50 107 87 83 193 154 51 111 ustr 

ALWp1 8.3 0.4 2.7 2.0 1.9 5.7 4.9 0.4 2.4 ksi 

ALWp2 -13.8 -16.5 -14.2 -15.0 -15.2 -11.9 -10.2 -16.2 -14.3 ksi 

ALWang 34 24 24 24 24 23 24 24 23 deg 

ALWvM 19.3 16.7 15.7 16.1 16.2 15.6 13.3 16.4 15.7 ksi 

ALW4 56 119 139 130 130 161 147 109 127 ustr 

ARF1 99 -125 -191 -165 -147 -357 -327 -168 -278 ustr 

ARF2 405 -239 -262 -246 -241 -286 -278 -233 -239 ustr 

ARF3 219 -184 -296 -260 -239 -465 -468 -262 -371 ustr 

ARF4 232 -120 -228 -191 -170 -403 -414 -192 -309 ustr 

BLBT -354 -408 -386 -391 -414 -363 -365 -361 -361 ustr 

BLBB 273 227 216 238 299 257 242 259 265 ustr 

BRBT -305 -383 -336 -356 -374 -346 -322 -346 -360 ustr 

BRBB 260 313 300 305 306 267 274 295 304 ustr 

ALBT 48 -374 -374 -394 -396 -377 -378 -418 -338 ustr 

ALBB 106 327 270 267 254 237 241 285 254 ustr 

ARBT -15 -279 -293 -299 -292 -315 -330 -309 -293 ustr 

ARBB -50 1303 193 184 176 254 237 186 205 ustr 
D-3 

Critical Region Compliance to 500 kips LCF Buff 

Stress Calculations

 

Sum Test 1-9 Std Dev Test 1 Test 2-6 Std Dev Test 7-9 Std Dev 

LCF_D 0 0 0 0 0 0 0 kip 

LCF -501 1 -502 -501 2 -501 1 kip 

VCFE_D 0 0 0 0 0 0 0 kip 

VCFE 0 0 0 0 0 0 0 kip 

VCFW_D 0 0 0 0 0 0 0 kip 

VCFW 0 1 0 0 0 0 1 kip 

SPE -0.14 0.05 0.00 -0.15 0.01 -0.16 0.02 in 

VCDE -0.15 0.01 -0.18 -0.15 0.01 -0.15 0.01 in 

SPW -0.12 0.05 0.00 -0.14 0.03 -0.14 0.01 in 

VCDW -0.19 0.01 -0.17 -0.19 0.01 -0.19 0.01 in 

BLH1 16.6 3.3 20.1 15.4 4.0 17.5 1.4 ksi 

BLH2 4.3 0.7 5.0 4.2 0.6 4.4 1.0 ksi 

BLH3 1.1 1.3 -1.9 1.1 0.3 2.0 0.7 ksi 

BLHp1 19.3 3.9 21.7 17.8 4.7 20.9 1.7 ksi 

BLHp2 5.1 1.2 3.3 4.9 0.6 6.1 1.2 ksi 

BLHang -15 4 -10 -14 4 -17 1 deg 

BLHvM 17.3 3.6 20.3 16.0 4.4 18.6 1.3 ksi 

BLH4 11.1 1.0 13.3 10.9 0.5 10.6 0.7 ksi 

BLW1 5.7 1.8 9.1 5.2 1.7 5.4 0.9 ksi 

BLW2 6.7 2.6 11.8 6.3 2.5 5.9 0.7 ksi 

BLW3 3.3 1.1 5.6 3.3 0.8 2.6 0.3 ksi 

BLW4 4.9 1.2 7.3 5.0 0.8 4.0 0.3 ksi 

BRH1 -0.2 0.4 -0.2 -0.4 0.5 0.0 0.4 ksi 

BRH2 8.2 0.9 9.5 8.0 0.8 8.3 1.1 ksi 

BRH3 20.4 1.5 22.4 20.1 1.1 20.4 2.2 ksi 

BRHp1 22.2 1.7 24.2 21.8 1.2 22.2 2.5 ksi 

BRHp2 5.7 0.8 6.4 5.4 0.8 5.9 1.0 ksi 

BRHang 5 1 4 5 1 5 0 deg 

BRHvM 20.0 1.5 21.8 19.6 1.0 19.9 2.1 ksi 

BRH4 12.2 0.8 13.6 12.1 0.6 12.1 1.0 ksi 

BRF1 -13.4 1.0 -12.0 -13.9 0.9 -13.2 0.8 ksi 

BRF2 2.4 20.9 -12.4 6.8 28.1 0.0 0.0 ksi 

BRF3 -19.5 1.5 -19.2 -19.8 1.7 -19.0 1.5 ksi 

BRF4 -16.4 5.1 -17.9 -14.8 6.6 -18.6 1.5 ksi 
D-4 

ALH1 4.6 4.3 -5.8 5.2 1.7 7.2 1.2 ksi 

ALH2 8.7 3.6 14.7 9.5 2.4 5.1 0.9 ksi 

ALH3 -5.6 2.1 -0.4 -5.8 0.7 -7.0 0.7 ksi 

ALHp1 8.2 1.6 9.8 8.5 1.6 7.0 1.2 ksi 

ALHp2 -9.5 3.9 -18.4 -9.4 1.8 -6.7 1.4 ksi 

ALHang 18 23 -41 30 5 18 3 deg 

ALHvM 15.4 4.3 24.8 15.6 2.4 11.9 0.6 ksi 

ALH4 5.7 1.8 9.6 5.9 0.9 4.1 0.2 ksi 

ALW1 -11.0 2.0 -7.4 -11.7 1.1 -11.0 2.4 ksi 

ALW2 -12.4 1.8 -15.0 -12.4 1.3 -11.5 2.2 ksi 

ALW3 3.1 1.3 3.5 3.0 1.6 3.1 1.5 ksi 

ALWp1 3.2 2.6 8.3 2.5 2.0 2.6 2.2 ksi 

ALWp2 -14.1 2.0 -13.8 -14.5 1.7 -13.6 3.1 ksi 

ALWang 25 3 34 24 1 23 1 deg 

ALWvM 16.1 1.6 19.3 16.1 0.5 15.1 1.6 ksi 

ALW4 3.6 0.9 1.6 3.9 0.5 3.7 0.5 ksi 

ARF1 -5.3 3.9 2.9 -5.7 2.7 -7.5 2.4 ksi 

ARF2 -5.2 6.4 11.7 -7.4 0.6 -7.2 0.7 ksi 

ARF3 -7.5 5.9 6.3 -8.4 3.1 -10.6 3.0 ksi 

ARF4 -5.8 5.6 6.7 -6.5 3.1 -8.8 3.2 ksi 

BLBT -11.0 0.6 -10.3 -11.4 0.6 -10.5 0.1 ksi 

BLBB 7.3 0.7 7.9 7.2 0.9 7.4 0.4 ksi 

BRBT -10.1 0.7 -8.8 -10.4 0.6 -9.9 0.5 ksi 

BRBB 8.5 0.6 7.5 8.7 0.5 8.4 0.4 ksi 

ALBT -9.7 4.2 1.4 -11.1 0.3 -11.0 1.2 ksi 

ALBB 7.2 1.7 3.1 7.9 1.0 7.5 0.7 ksi 

ARBT -7.8 2.8 -0.4 -8.6 0.4 -9.0 0.5 ksi 

ARBB 8.7 11.2 -1.4 12.2 14.3 6.1 0.7 ksi 
D-5 

D-II. LCF Draft Compliance Peaks 

Critical Region Compliance to 500 kips LCF Draft 

Strain Data

 (Test 1) (Test 2) (Test 3) (Test 4) (Test 5) (Test 6) (Test 7) (Test 8) (Test 9) 

Mileage 0 0 50,000 100,000 150,000 200,000 200,000 250,000 300,000 spec mi 

LCF_D 0 0 0 0 0 0 0 0 0 kip 

LCF 501 477 493 494 493 490 498 489 493 kip 

VCFE_D 0 0 0 2 0 0 0 0 0 kip 

VCFE 0 0 0 0 0 0 1 0 0 kip 

VCFW_D 0 0 0 0 0 0 0 0 0 kip 

VCFW 0 0 0 0 0 0 -1 3 0 kip 

SPE 0.00 0.05 0.09 0.06 0.07 0.12 0.11 0.06 0.05 in 

VCDE 0.20 0.16 0.14 0.14 0.14 0.19 0.20 0.14 0.12 in 

SPW 0.00 0.05 0.08 0.08 0.06 0.14 0.14 0.09 0.10 in 

VCDW 0.17 0.16 0.17 0.18 0.17 0.20 0.19 0.19 0.16 in 

BLH1 -620 -366 -318 -345 130 -440 -499 -363 -269 ustr 

BLH2 -118 18 63 54 83 -88 -50 24 72 ustr 

BLH3 77 92 83 76 86 14 13 44 52 ustr 

BLHp1 -2.2 0.8 1.4 1.0 5.1 -2.6 -2.4 -0.2 1.2 ksi 

BLHp2 -19.5 -11.8 -10.8 -11.8 3.5 -14.4 -17.0 -12.6 -9.8 ksi 

BLHang -12 -17 -21 -21 -24 -14 -19 -21 -24 deg 

BLHvM 18.5 12.2 11.6 12.4 4.5 13.3 15.9 12.5 10.5 ksi 

BLH4 -415 -258 -222 -234 -210 -351 -300 -234 -180 ustr 

BLW1 -64 71 -6 -38 12 -51 -8 60 56 ustr 

BLW2 -181 -67 -135 -171 -111 -180 -134 -53 -61 ustr 

BLW3 -233 -112 -125 -137 -135 -152 -126 -99 -78 ustr 

BLW4 -111 -140 -153 -172 -169 -188 -161 -131 -104 ustr 

BRH1 52 80 96 98 113 25 49 92 118 ustr 

BRH2 -237 -86 -41 -52 -17 -228 -156 -54 20 ustr 

BRH3 -688 -431 -376 -394 -343 -686 -564 -392 -283 ustr 

BRHp1 -4.1 -0.9 0.2 0.1 1.0 -4.8 -3.0 -0.1 1.8 ksi 

BRHp2 -21.3 -13.2 -11.4 -11.9 -10.3 -21.6 -17.6 -11.9 -8.4 ksi 

BRHang 6 10 11 11 12 8 9 11 14 deg 

BRHvM 19.6 12.8 11.5 12.0 10.8 19.7 16.4 11.9 9.5 ksi 

BRH4 -420 -273 -243 -256 -231 -383 -327 -253 -196 ustr 

BRF1 605 538 578 583 594 580 565 559 573 ustr 

BRF2 636 1425 3108 1837 0 0 0 0 0 ustr 

BRF3 886 760 787 781 784 788 800 774 759 ustr 

BRF4 868 342 269 795 808 815 799 779 792 ustr 
D-6 

ALH1 121 54 31 28 29 -79 -24 20 -1 ustr 

ALH2 -646 -674 -723 -753 -742 -856 -800 -714 -685 ustr 

ALH3 -140 -184 -206 -212 -206 -198 -189 -197 -166 ustr 

ALHp1 14.4 11.5 11.2 11.6 11.5 10.8 11.7 10.9 10.5 ksi 

ALHp2 -15.2 -16.7 -18.2 -19.0 -18.7 -21.9 -20.1 -18.0 -17.2 ksi 

ALHang -39 -39 -40 -40 -40 -43 -42 -40 -41 deg 

ALHvM 25.6 24.6 25.7 26.7 26.4 28.9 27.9 25.3 24.2 ksi 

ALH4 -377 -349 -363 -380 -373 -388 -384 -364 -316 ustr 

ALW1 595 460 458 465 466 524 491 450 486 ustr 

ALW2 465 451 462 473 465 551 509 446 471 ustr 

ALW3 -70 -55 -39 -45 -49 14 -22 -44 12 ustr 

ALWp1 19.4 16.2 16.4 16.7 16.6 19.4 17.9 16.0 17.4 ksi 

ALWp2 1.7 0.0 0.3 0.1 0.1 2.1 0.8 0.2 2.6 ksi 

ALWang 16 22 23 23 22 24 23 22 22 deg 

ALWvM 18.6 16.3 16.3 16.7 16.6 18.4 17.5 15.9 16.2 ksi 

ALW4 -271 -177 -174 -180 -178 -184 -183 -177 -157 ustr 

ARF1 613 488 471 465 470 477 462 459 458 ustr 

ARF2 851 186 203 201 203 271 223 195 194 ustr 

ARF3 881 599 590 576 576 655 599 549 555 ustr 

ARF4 793 586 576 565 566 625 583 553 559 ustr 

BLBT 608 521 564 586 576 588 586 551 561 ustr 

BLBB 436 354 346 333 393 373 381 398 404 ustr 

BRBT 525 461 516 542 546 547 533 482 498 ustr 

BRBB 494 509 499 502 481 494 516 540 547 ustr 

ALBT 648 548 577 571 571 666 613 580 643 ustr 

ALBB 481 425 412 419 404 433 424 447 441 ustr 

ARBT 596 475 492 489 493 565 514 499 537 ustr 

ARBB 470 604 373 368 352 407 371 374 391 ustr 
D-7 

Critical Region Compliance to 500 kips LCF Draft 

Stress Calculations

 

Sum Test 1-9 Std Dev Test 1 Test 2-6 Std Dev Test 7-9 Std Dev 

LCF_D 0 0 0 0 0 0 0 kip 

LCF 492 7 501 490 7 494 5 kip 

VCFE_D 0 1 0 0 1 0 0 kip 

VCFE 0 0 0 0 0 0 1 kip 

VCFW_D 0 0 0 0 0 0 0 kip 

VCFW 0 1 0 0 0 1 2 kip 

SPE 0.07 0.04 0.00 0.08 0.03 0.07 0.03 in 

VCDE 0.16 0.03 0.20 0.15 0.02 0.15 0.04 in 

SPW 0.08 0.04 0.00 0.08 0.03 0.11 0.03 in 

VCDW 0.18 0.01 0.17 0.18 0.02 0.18 0.02 in 

BLH1 -10.0 6.0 -18.0 -7.8 6.6 -10.9 3.4 ksi 

BLH2 0.2 2.1 -3.4 0.8 2.0 0.5 1.8 ksi 

BLH3 1.7 0.9 2.2 2.0 0.9 1.1 0.6 ksi 

BLHp1 0.2 2.4 -2.2 1.1 2.7 -0.5 1.8 ksi 

BLHp2 -11.6 6.5 -19.5 -9.1 7.2 -13.1 3.6 ksi 

BLHang -19 4 -12 -20 4 -21 3 deg 

BLHvM 12.4 3.8 18.5 10.8 3.6 13.0 2.8 ksi 

BLH4 -7.7 2.2 -12.0 -7.4 1.6 -6.9 1.7 ksi 

BLW1 0.1 1.4 -1.9 -0.1 1.4 1.0 1.1 ksi 

BLW2 -3.5 1.5 -5.2 -3.9 1.3 -2.4 1.3 ksi 

BLW3 -3.9 1.3 -6.8 -3.8 0.4 -2.9 0.7 ksi 

BLW4 -4.3 0.8 -3.2 -4.8 0.5 -3.8 0.8 ksi 

BRH1 2.3 0.9 1.5 2.4 1.0 2.5 1.0 ksi 

BRH2 -2.7 2.7 -6.9 -2.5 2.4 -1.8 2.6 ksi 

BRH3 -13.4 4.3 -19.9 -12.9 4.0 -12.0 4.1 ksi 

BRHp1 -1.1 2.3 -4.1 -0.9 2.3 -0.4 2.4 ksi 

BRHp2 -14.2 4.8 -21.3 -13.7 4.6 -12.7 4.7 ksi 

BRHang 10 2 6 10 1 11 2 deg 

BRHvM 13.8 3.8 19.6 13.4 3.6 12.6 3.5 ksi 

BRH4 -8.3 2.2 -12.2 -8.0 1.8 -7.5 1.9 ksi 

BRF1 16.7 0.6 17.5 16.7 0.6 16.4 0.2 ksi 

BRF2 22.6 32.4 18.5 36.9 38.2 0.0 0.0 ksi 

BRF3 22.9 1.1 25.7 22.6 0.3 22.5 0.6 ksi 

BRF4 20.2 6.5 25.2 17.6 8.0 22.9 0.3 ksi 
D-8 

ALH1 0.6 1.6 3.5 0.4 1.5 0.0 0.6 ksi 

ALH2 -21.2 1.9 -18.7 -21.7 1.9 -21.3 1.7 ksi 

ALH3 -5.5 0.7 -4.1 -5.8 0.3 -5.3 0.5 ksi 

ALHp1 11.6 1.1 14.4 11.3 0.3 11.0 0.6 ksi 

ALHp2 -18.3 2.0 -15.2 -18.9 1.9 -18.4 1.5 ksi 

ALHang -40 1 -39 -40 1 -41 1 deg 

ALHvM 26.1 1.5 25.6 26.5 1.6 25.8 1.9 ksi 

ALH4 -10.6 0.6 -10.9 -10.7 0.4 -10.3 1.0 ksi 

ALW1 14.2 1.3 17.3 13.8 0.8 13.8 0.7 ksi 

ALW2 13.8 1.0 13.5 13.9 1.2 13.8 0.9 ksi 

ALW3 -1.0 0.8 -2.0 -1.0 0.8 -0.5 0.8 ksi 

ALWp1 17.3 1.3 19.4 17.1 1.3 17.1 1.0 ksi 

ALWp2 0.9 1.0 1.7 0.5 0.9 1.2 1.2 ksi 

ALWang 22 2 16 23 1 22 1 deg 

ALWvM 16.9 1.0 18.6 16.9 0.9 16.5 0.9 ksi 

ALW4 -5.4 0.9 -7.9 -5.2 0.1 -5.0 0.4 ksi 

ARF1 14.1 1.4 17.8 13.8 0.3 13.3 0.1 ksi 

ARF2 8.1 6.2 24.7 6.2 1.0 5.9 0.5 ksi 

ARF3 18.0 3.0 25.6 17.4 0.9 16.5 0.8 ksi 

ARF4 17.4 2.2 23.0 16.9 0.7 16.4 0.5 ksi 

BLBT 16.6 0.7 17.6 16.4 0.8 16.4 0.5 ksi 

BLBB 11.0 0.9 12.6 10.4 0.7 11.4 0.4 ksi 

BRBT 15.0 0.9 15.2 15.1 1.1 14.6 0.8 ksi 

BRBB 14.8 0.6 14.3 14.4 0.3 15.5 0.5 ksi 

ALBT 17.5 1.2 18.8 17.0 1.3 17.8 0.9 ksi 

ALBB 12.5 0.7 13.9 12.1 0.3 12.7 0.3 ksi 

ARBT 15.0 1.2 17.3 14.6 1.0 15.0 0.6 ksi 

ARBB 12.0 2.3 13.6 12.2 3.0 11.0 0.3 ksi 
D-9 

D-III. Upward VCF Compliance Peaks 

Critical Region Compliance to 50 kips Upward VCF 

Strain Data

 (Test 1) (Test 2) (Test 3) (Test 4) (Test 5) (Test 6) (Test 7) (Test 8) (Test 9) 

Mileage 0 0 50,000 100,000 150,000 200,000 200,000 250,000 300,000 spec mi 

LCF_D 0 0 0 0 0 0 0 0 0 kip 

LCF 0 0 0 0 0 0 0 0 0 kip 

VCFE_D 0 0 0 0 0 0 0 0 0 kip 

VCFE 49 50 50 50 50 50 49 50 50 kip 

VCFW_D 0 0 0 0 0 0 0 0 0 kip 

VCFW 50 50 50 50 50 50 50 50 49 kip 

SPE 0.00 0.05 0.05 0.05 0.05 0.04 0.06 0.06 0.07 in 

VCDE 0.20 0.19 0.19 0.19 0.19 0.20 0.20 0.20 0.21 in 

SPW 0.00 0.06 0.04 0.05 0.03 0.05 0.05 0.06 0.06 in 

VCDW 0.25 0.24 0.23 0.23 0.23 0.24 0.23 0.24 0.24 in 

BLH1 -725 -720 -679 -671 -812 -813 -745 -671 -709 ustr 

BLH2 -595 -603 -569 -557 -559 -552 -551 -548 -564 ustr 

BLH3 -223 -227 -200 -193 -192 -173 -181 -167 -170 ustr 

BLHp1 -12.6 -12.6 -11.4 -11.1 -12.9 -12.3 -11.8 -10.3 -10.8 ksi 

BLHp2 -25.3 -25.3 -23.8 -23.4 -27.2 -27.1 -25.2 -23.2 -24.3 ksi 

BLHang 13 14 14 14 5 5 9 14 12 deg 

BLHvM 21.9 21.9 20.6 20.3 23.6 23.5 21.9 20.1 21.1 ksi 

BLH4 -380 -375 -356 -351 -351 -359 -353 -356 -376 ustr 

BLW1 9 -92 -119 -124 -133 -131 -118 -128 -134 ustr 

BLW2 -62 -174 -174 -183 -189 -168 -146 -173 -201 ustr 

BLW3 -76 -93 -112 -105 -114 -114 -98 -106 -102 ustr 

BLW4 -112 -125 -141 -129 -141 -133 -111 -127 -122 ustr 

BRH1 -334 -314 -308 -307 -304 -305 -309 -308 -310 ustr 

BRH2 -663 -626 -615 -609 -602 -615 -615 -615 -623 ustr 

BRH3 -765 -704 -686 -680 -672 -706 -699 -690 -718 ustr 

BRHp1 -16.4 -15.2 -14.8 -14.8 -14.6 -15.0 -15.1 -14.9 -15.3 ksi 

BRHp2 -27.5 -25.5 -24.9 -24.7 -24.5 -25.4 -25.3 -25.0 -25.8 ksi 

BRHang -14 -16 -16 -16 -16 -14 -15 -16 -14 deg 

BRHvM 24.0 22.2 21.7 21.5 21.3 22.1 22.0 21.8 22.5 ksi 

BRH4 -361 -338 -327 -323 -321 -338 -336 -332 -342 ustr 

BRF1 -376 -356 -345 -348 -340 -331 -343 -348 -354 ustr 

BRF2 -2027 -1489 -5743 -4466 0 0 0 0 0 ustr 

BRF3 -629 -603 -549 -552 -539 -503 -582 -533 -509 ustr 

BRF4 -557 -245 -113 -531 -514 -489 -523 -523 -512 ustr 
D-10 

ALH1 -346 -347 -340 -340 -342 -344 -337 -339 -332 ustr 

ALH2 -966 -938 -907 -888 -906 -849 -770 -878 -854 ustr 

ALH3 -843 -792 -782 -757 -775 -696 -636 -759 -728 ustr 

ALHp1 -13.6 -13.0 -13.1 -12.9 -13.1 -12.3 -12.2 -13.1 -12.6 ksi 

ALHp2 -34.0 -32.6 -31.8 -31.0 -31.7 -29.3 -26.8 -30.8 -29.8 ksi 

ALHang -28 -29 -29 -29 -29 -31 -31 -29 -29 deg 

ALHvM 29.6 28.4 27.7 27.0 27.6 25.5 23.2 26.8 25.9 ksi 

ALH4 -422 -387 -371 -358 -367 -343 -318 -357 -340 ustr 

ALW1 -231 -259 -255 -256 -256 -245 -243 -253 -250 ustr 

ALW2 -119 -141 -145 -153 -149 -144 -154 -150 -146 ustr 

ALW3 30 16 19 19 19 20 7 19 23 ustr 

ALWp1 -1.0 -1.7 -1.5 -1.5 -1.5 -1.4 -1.8 -1.5 -1.3 ksi 

ALWp2 -7.0 -8.0 -7.9 -8.0 -7.9 -7.6 -7.7 -7.9 -7.7 ksi 

ALWang 4 4 6 7 6 7 8 7 7 deg 

ALWvM 6.6 7.3 7.2 7.3 7.3 7.0 7.0 7.2 7.2 ksi 

ALW4 -62 -63 -58 -57 -59 -55 -53 -57 -55 ustr 

ARF1 -406 -403 -408 -406 -409 -405 -405 -398 -396 ustr 

ARF2 -1029 -820 -829 -792 -811 -788 -747 -796 -667 ustr 

ARF3 -631 -602 -613 -597 -606 -613 -632 -593 -558 ustr 

ARF4 -487 -464 -475 -466 -471 -477 -502 -462 -445 ustr 

BLBT -179 -178 -165 -181 -179 -167 -173 -179 -175 ustr 

BLBB 189 160 178 190 216 218 208 206 209 ustr 

BRBT -179 -175 -170 -173 -169 -161 -167 -177 -175 ustr 

BRBB 182 178 175 174 172 173 169 177 184 ustr 

ALBT -191 -186 -191 -189 -192 -181 -210 -189 -185 ustr 

ALBB 199 196 193 190 194 174 178 192 188 ustr 

ARBT -206 -195 -200 -195 -197 -190 -214 -195 -188 ustr 

ARBB 202 0 195 190 194 187 183 193 186 ustr 
D-11 

Critical Region Compliance to 50 kips Upward VCF 

Stress Calculations

 

Sum Test 1-9 Std Dev Test 1 Test 2-6 Std Dev Test 7-9 Std Dev 

LCF_D 0 0 0 0 0 0 0 kip 

LCF 0 0 0 0 0 0 0 kip 

VCFE_D 0 0 0 0 0 0 0 kip 

VCFE 50 0 49 50 0 50 0 kip 

VCFW_D 0 0 0 0 0 0 0 kip 

VCFW 50 0 50 50 0 50 1 kip 

SPE 0.05 0.02 0.00 0.05 0.00 0.06 0.01 in 

VCDE 0.20 0.01 0.20 0.19 0.00 0.20 0.01 in 

SPW 0.04 0.02 0.00 0.05 0.01 0.06 0.01 in 

VCDW 0.24 0.01 0.25 0.23 0.01 0.24 0.01 in 

BLH1 -21.1 1.6 -21.0 -21.4 2.0 -20.5 1.1 ksi 

BLH2 -16.4 0.6 -17.2 -16.5 0.6 -16.1 0.3 ksi 

BLH3 -5.6 0.6 -6.5 -5.7 0.6 -5.0 0.2 ksi 

BLHp1 -11.8 0.9 -12.6 -12.1 0.8 -11.0 0.8 ksi 

BLHp2 -25.0 1.5 -25.3 -25.4 1.8 -24.3 1.0 ksi 

BLHang 11 4 13 10 5 12 3 deg 

BLHvM 21.7 1.3 21.9 22.0 1.6 21.0 0.9 ksi 

BLH4 -10.5 0.3 -11.0 -10.4 0.3 -10.5 0.4 ksi 

BLW1 -3.1 1.3 0.3 -3.5 0.5 -3.7 0.2 ksi 

BLW2 -4.7 1.2 -1.8 -5.2 0.2 -5.0 0.8 ksi 

BLW3 -3.0 0.4 -2.2 -3.1 0.3 -3.0 0.1 ksi 

BLW4 -3.7 0.3 -3.2 -3.9 0.2 -3.5 0.2 ksi 

BRH1 -9.0 0.3 -9.7 -8.9 0.1 -9.0 0.0 ksi 

BRH2 -18.0 0.5 -19.2 -17.8 0.3 -17.9 0.1 ksi 

BRH3 -20.4 0.8 -22.2 -20.0 0.4 -20.4 0.4 ksi 

BRHp1 -15.1 0.5 -16.4 -14.9 0.2 -15.1 0.2 ksi 

BRHp2 -25.4 0.9 -27.5 -25.0 0.5 -25.4 0.4 ksi 

BRHang -15 1 -14 -16 1 -15 1 deg 

BRHvM 22.1 0.8 24.0 21.8 0.4 22.1 0.3 ksi 

BRH4 -9.7 0.3 -10.5 -9.6 0.2 -9.8 0.2 ksi 

BRF1 -10.1 0.4 -10.9 -10.0 0.3 -10.1 0.1 ksi 

BRF2 -44.2 63.5 -58.8 -67.8 76.4 0.0 0.0 ksi 

BRF3 -16.1 1.2 -18.2 -15.9 1.0 -15.7 1.1 ksi 

BRF4 -12.9 4.5 -16.2 -11.0 5.5 -15.1 0.2 ksi 
D-12 

ALH1 -9.9 0.1 -10.0 -9.9 0.1 -9.7 0.1 ksi 

ALH2 -25.6 1.6 -28.0 -26.0 0.9 -24.2 1.6 ksi 

ALH3 -21.8 1.7 -24.5 -22.1 1.1 -20.5 1.9 ksi 

ALHp1 -12.9 0.5 -13.6 -12.9 0.3 -12.6 0.5 ksi 

ALHp2 -30.9 2.1 -34.0 -31.3 1.2 -29.1 2.1 ksi 

ALHang -29 1 -28 -29 1 -30 1 deg 

ALHvM 26.8 1.8 29.6 27.2 1.1 25.3 1.9 ksi 

ALH4 -10.5 0.9 -12.2 -10.6 0.5 -9.8 0.6 ksi 

ALW1 -7.2 0.3 -6.7 -7.4 0.2 -7.2 0.2 ksi 

ALW2 -4.2 0.3 -3.5 -4.2 0.1 -4.3 0.1 ksi 

ALW3 0.6 0.2 0.9 0.5 0.1 0.5 0.2 ksi 

ALWp1 -1.5 0.2 -1.0 -1.5 0.1 -1.5 0.2 ksi 

ALWp2 -7.7 0.3 -7.0 -7.9 0.2 -7.8 0.1 ksi 

ALWang 6 1 4 6 1 7 1 deg 

ALWvM 7.1 0.2 6.6 7.2 0.1 7.1 0.1 ksi 

ALW4 -1.7 0.1 -1.8 -1.7 0.1 -1.6 0.1 ksi 

ARF1 -11.7 0.1 -11.8 -11.8 0.1 -11.6 0.1 ksi 

ARF2 -23.5 2.8 -29.8 -23.4 0.5 -21.4 1.9 ksi 

ARF3 -17.5 0.6 -18.3 -17.6 0.2 -17.2 1.1 ksi 

ARF4 -13.7 0.5 -14.1 -13.7 0.2 -13.6 0.8 ksi 

BLBT -5.1 0.2 -5.2 -5.1 0.2 -5.1 0.1 ksi 

BLBB 5.7 0.6 5.5 5.6 0.7 6.0 0.1 ksi 

BRBT -5.0 0.2 -5.2 -4.9 0.2 -5.0 0.1 ksi 

BRBB 5.1 0.1 5.3 5.1 0.1 5.1 0.2 ksi 

ALBT -5.5 0.2 -5.6 -5.4 0.1 -5.6 0.4 ksi 

ALBB 5.5 0.2 5.8 5.5 0.3 5.4 0.2 ksi 

ARBT -5.7 0.2 -6.0 -5.7 0.1 -5.8 0.4 ksi 

ARBB 4.9 1.9 5.9 4.4 2.5 5.4 0.2 ksi 
D-13 

D-IV. Downward VCF Compliance Peaks 

Critical Region Compliance to 50 kips Downward VCF 

Strain Data

 (Test 1) (Test 2) (Test 3) (Test 4) (Test 5) (Test 6) (Test 7) (Test 8) (Test 9) 

Mileage 0 0 50,000 100,000 150,000 200,000 200,000 250,000 300,000 spec mi 

LCF_D 0 0 0 0 0 0 0 0 0 kip 

LCF 1 0 0 0 0 1 0 0 0 kip 

VCFE_D 0 0 0 0 0 0 0 0 0 kip 

VCFE -50 -50 -50 -50 -50 -50 -49 -50 -50 kip 

VCFW_D 0 0 0 0 0 0 0 0 0 kip 

VCFW -50 -50 -50 -50 -50 -50 -52 -50 -50 kip 

SPE 0.00 -0.06 -0.07 -0.06 -0.06 -0.07 -0.07 -0.06 -0.07 in 

VCDE -0.25 -0.24 -0.24 -0.23 -0.24 -0.25 -0.23 -0.25 -0.25 in 

SPW 0.00 -0.05 -0.07 -0.08 -0.07 -0.08 -0.09 -0.08 -0.09 in 

VCDW -0.30 -0.25 -0.26 -0.26 -0.26 -0.26 -0.27 -0.27 -0.26 in 

BLH1 755 655 621 607 980 979 797 600 560 ustr 

BLH2 627 534 505 496 494 476 456 470 444 ustr 

BLH3 245 162 158 163 157 147 136 131 113 ustr 

BLHp1 26.5 22.6 21.5 21.0 32.2 32.2 26.2 20.5 19.1 ksi 

BLHp2 13.5 10.1 9.7 9.7 13.2 12.9 11.1 8.8 7.8 ksi 

BLHang 13 13 13 13 -5 -6 -1 12 13 deg 

BLHvM 22.9 19.6 18.6 18.2 28.1 28.1 22.7 17.8 16.6 ksi 

BLH4 400 337 321 308 314 309 297 316 302 ustr 

BLW1 -5 44 40 46 43 12 11 0 -4 ustr 

BLW2 95 36 4 8 5 -49 -45 -56 -77 ustr 

BLW3 73 64 73 54 62 58 52 42 46 ustr 

BLW4 114 68 70 46 54 47 40 34 38 ustr 

BRH1 360 321 318 320 321 325 320 328 326 ustr 

BRH2 700 617 608 605 611 616 599 617 617 ustr 

BRH3 799 715 708 706 716 730 711 744 740 ustr 

BRHp1 28.9 25.7 25.5 25.4 25.7 26.1 25.5 26.5 26.4 ksi 

BRHp2 17.5 15.7 15.6 15.7 15.8 16.1 15.8 16.4 16.2 ksi 

BRHang -14 -13 -13 -13 -13 -12 -12 -11 -11 deg 

BRHvM 25.2 22.5 22.2 22.2 22.4 22.8 22.3 23.2 23.1 ksi 

BRH4 376 332 327 321 327 331 323 335 335 ustr 

BRF1 372 367 355 360 359 363 357 370 363 ustr 

BRF2 759 1817 0 0 0 0 0 0 0 ustr 

BRF3 736 571 557 552 550 536 553 541 521 ustr 

BRF4 600 237 295 530 528 532 521 523 516 ustr 
D-14 

ALH1 332 465 515 543 539 605 629 598 642 ustr 

ALH2 910 339 346 270 288 152 132 198 157 ustr 

ALH3 812 239 233 196 209 157 160 181 171 ustr 

ALHp1 32.3 16.7 18.2 19.3 19.2 22.5 23.8 22.0 24.1 ksi 

ALHp2 13.5 11.5 11.7 10.2 10.7 8.0 7.8 9.1 8.5 ksi 

ALHang -27 -3 -6 -15 -14 -23 -24 -21 -23 deg 

ALHvM 28.1 14.8 16.0 16.8 16.6 19.8 21.0 19.2 21.2 ksi 

ALH4 399 119 112 82 91 34 34 52 26 ustr 

ALW1 231 253 249 246 243 240 238 252 252 ustr 

ALW2 115 167 157 149 150 152 140 153 154 ustr 

ALW3 -32 -64 -74 -87 -81 -87 -98 -86 -89 ustr 

ALWp1 7.0 7.7 7.5 7.3 7.3 7.1 6.9 7.5 7.5 ksi 

ALWp2 1.0 -0.2 -0.5 -0.9 -0.8 -1.0 -1.3 -0.8 -0.9 ksi 

ALWang 3 12 12 11 12 12 11 11 11 deg 

ALWvM 6.5 7.8 7.8 7.8 7.7 7.7 7.7 7.9 8.0 ksi 

ALW4 66 25 24 18 21 17 14 17 13 ustr 

ARF1 409 425 424 431 426 431 464 440 438 ustr 

ARF2 1124 -97 -108 -102 -107 -108 -102 -84 -50 ustr 

ARF3 660 370 348 352 343 339 374 334 318 ustr 

ARF4 506 389 373 380 371 374 417 366 348 ustr 

BLBT 177 174 192 163 176 186 172 167 172 ustr 

BLBB -190 -160 -178 -173 -201 -210 -187 -194 -201 ustr 

BRBT 175 167 171 157 163 176 165 165 166 ustr 

BRBB -216 -208 -202 -204 -201 -208 -217 -212 -204 ustr 

ALBT 179 187 182 174 168 174 172 191 159 ustr 

ALBB -186 -197 -200 -199 -199 -195 -178 -196 -204 ustr 

ARBT 191 195 185 186 178 182 189 194 173 ustr 

ARBB -204 0 -193 -197 -192 -196 -217 -197 -195 ustr 
D-15 

Critical Region Compliance to 50 kips Downward VCF 

Stress Calculations

 

Sum Test 1-9 Std Dev Test 1 Test 2-6 Std Dev Test 7-9 Std Dev 

LCF_D 0 0 0 0 0 0 0 kip 

LCF 0 0 1 0 0 0 0 kip 

VCFE_D 0 0 0 0 0 0 0 kip 

VCFE -50 0 -50 -50 0 -50 0 kip 

VCFW_D 0 0 0 0 0 0 0 kip 

VCFW -50 1 -50 -50 0 -51 1 kip 

SPE -0.06 0.02 0.00 -0.06 0.01 -0.07 0.01 in 

VCDE -0.24 0.01 -0.25 -0.24 0.01 -0.24 0.01 in 

SPW -0.07 0.03 0.00 -0.07 0.01 -0.09 0.01 in 

VCDW -0.27 0.01 -0.30 -0.26 0.00 -0.27 0.01 in 

BLH1 21.1 4.7 21.9 22.3 5.6 18.9 3.7 ksi 

BLH2 14.5 1.6 18.2 14.5 0.6 13.2 0.4 ksi 

BLH3 4.6 1.1 7.1 4.6 0.2 3.7 0.3 ksi 

BLHp1 24.6 4.9 26.5 25.9 5.8 21.9 3.8 ksi 

BLHp2 10.8 2.0 13.5 11.1 1.8 9.3 1.7 ksi 

BLHang 7 9 13 6 10 8 8 deg 

BLHvM 21.4 4.3 22.9 22.5 5.1 19.0 3.3 ksi 

BLH4 9.4 0.9 11.6 9.2 0.3 8.8 0.3 ksi 

BLW1 0.6 0.6 -0.1 1.1 0.4 0.1 0.2 ksi 

BLW2 -0.3 1.6 2.8 0.0 0.9 -1.7 0.5 ksi 

BLW3 1.7 0.3 2.1 1.8 0.2 1.4 0.1 ksi 

BLW4 1.6 0.7 3.3 1.7 0.3 1.1 0.1 ksi 

BRH1 9.5 0.4 10.4 9.3 0.1 9.4 0.1 ksi 

BRH2 18.0 0.9 20.3 17.7 0.1 17.7 0.3 ksi 

BRH3 21.2 0.9 23.2 20.7 0.3 21.2 0.5 ksi 

BRHp1 26.2 1.1 28.9 25.7 0.3 26.1 0.6 ksi 

BRHp2 16.1 0.6 17.5 15.8 0.2 16.1 0.3 ksi 

BRHang -12 1 -14 -13 1 -11 0 deg 

BRHvM 22.9 0.9 25.2 22.4 0.2 22.8 0.5 ksi 

BRH4 9.7 0.5 10.9 9.5 0.1 9.6 0.2 ksi 

BRF1 10.5 0.2 10.8 10.5 0.1 10.5 0.2 ksi 

BRF2 8.3 18.2 22.0 10.5 23.6 0.0 0.0 ksi 

BRF3 16.5 1.9 21.4 16.0 0.4 15.6 0.5 ksi 

BRF4 13.8 3.5 17.4 12.3 4.2 15.1 0.1 ksi 
D-16 

ALH1 15.7 2.8 9.6 15.5 1.5 18.1 0.7 ksi 

ALH2 9.0 6.9 26.4 8.1 2.3 4.7 1.0 ksi 

ALH3 7.6 6.0 23.5 6.0 1.0 5.0 0.3 ksi 

ALHp1 22.0 4.6 32.3 19.2 2.1 23.3 1.1 ksi 

ALHp2 10.1 1.9 13.5 10.4 1.5 8.5 0.7 ksi 

ALHang -17 9 -27 -12 8 -23 1 deg 

ALHvM 19.3 4.0 28.1 16.8 1.8 20.4 1.1 ksi 

ALH4 3.1 3.4 11.6 2.5 1.0 1.1 0.4 ksi 

ALW1 7.1 0.2 6.7 7.1 0.1 7.2 0.2 ksi 

ALW2 4.3 0.4 3.3 4.5 0.2 4.3 0.2 ksi 

ALW3 -2.2 0.6 -0.9 -2.3 0.3 -2.6 0.2 ksi 

ALWp1 7.3 0.3 7.0 7.4 0.2 7.3 0.3 ksi 

ALWp2 -0.6 0.7 1.0 -0.7 0.3 -1.0 0.3 ksi 

ALWang 11 3 3 12 0 11 0 deg 

ALWvM 7.7 0.4 6.5 7.8 0.1 7.9 0.2 ksi 

ALW4 0.7 0.5 1.9 0.6 0.1 0.4 0.1 ksi 

ARF1 12.5 0.4 11.9 12.4 0.1 13.0 0.4 ksi 

ARF2 1.2 11.8 32.6 -3.0 0.1 -2.3 0.8 ksi 

ARF3 11.1 3.1 19.1 10.2 0.3 9.9 0.8 ksi 

ARF4 11.4 1.4 14.7 10.9 0.2 10.9 1.0 ksi 

BLBT 5.1 0.3 5.1 5.2 0.3 4.9 0.1 ksi 

BLBB -5.5 0.5 -5.5 -5.4 0.6 -5.6 0.2 ksi 

BRBT 4.8 0.2 5.1 4.8 0.2 4.8 0.0 ksi 

BRBB -6.0 0.2 -6.3 -5.9 0.1 -6.1 0.2 ksi 

ALBT 5.1 0.3 5.2 5.1 0.2 5.0 0.5 ksi 

ALBB -5.7 0.2 -5.4 -5.7 0.1 -5.6 0.4 ksi 

ARBT 5.4 0.2 5.5 5.4 0.2 5.4 0.3 ksi 

ARBB -5.1 1.9 -5.9 -4.5 2.5 -5.9 0.3 ksi 
E-1 

Appendix E. 

Rainflow Cycle-Counted Drive and Response Data 

E-1. VCF Response 
E-2 
E-3 

E-II. LCF Response 
E-4