U.S. Department of 

Transportation

Federal Railroad 

Administration

800,000-Pound Quasi-Static End-Load Test of 

Crash Energy Management Equipped Car, Test 2

Office of Research

and Development

Washington, DC 20590

DOT/FRA/ORD-13/04 Final Report

February 2013
NOTICE

This document is disseminated under the sponsorship of the 

Department of Transportation in the interest of information 

exchange. The United States Government assumes no liability for 

its contents or use thereof. Any opinions, findings and 

conclusions, or recommendations expressed in this material do not 

necessarily reflect the views or policies of the United States 

Government, nor does mention of trade names, commercial 

products, or organizations imply endorsement by the United States 

Government. The United States Government assumes no liability 

for the content or use of the material contained in this document.

NOTICE

The United States Government does not endorse products or 

manufacturers. Trade or manufacturers’ names appear herein 

solely because they are considered essential to the objective of this 

report.
i

REPORT DOCUMENTATION PAGE Form Approved

OMB No. 0704-0188

Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302, and to the Office of Management and Budget, Paperwork Reduction Project (0704-0188), Washington, DC 20503.

1. AGENCY USE ONLY (Leave blank) 2. REPORT DATE

February 2013

3. REPORT TYPE AND DATES COVERED

Technical Report

4. TITLE AND SUBTITLE

800,000-Pound Quasi-Static End Load Test of Crash Energy Management Equipped Car,

Test 2

5. FUNDING NUMBERS

DTFR-53-00-0012

6. AUTHOR(S) and FRA COTM Task Order 235

Robert H. Fries, Lucy Tunna, Satima Anankitpaiboon, and Luis Maal

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

Transportation Technology Center, Inc.

55500 DOT Road

Pueblo, Colorado 81001

8. PERFORMING ORGANIZATION 

REPORT NUMBER

9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)

U.S. Department of Transportation 

Federal Railroad Administration

Office of Research and Development

Washington, DC 20590

10. SPONSORING/MONITORING

AGENCY REPORT NUMBER

DOT/FRA/ORD-13/04

11. SUPPLEMENTARY NOTES

Program Manager: Luis Maal

12a. DISTRIBUTION/AVAILABILITY STATEMENT

This document is available to the public through the FRA Web site at http://www.fra.dot.gov.

12b. DISTRIBUTION CODE

13. ABSTRACT (Maximum 200 words)

This report summarizes compressive end-load Test 2 on Budd Pioneer Car 244. The quasi-static compressive end-load test at 

800,000 pounds was conducted on January 19, 2011. The test vehicle has been modified to include a crash energy management

system and has been assessed in full-scale tests six times previously. Test 2 results indicate Car 244 is suitable for an additional 

test. 

14. SUBJECT TERMS

Quasi-static test

15. NUMBER OF PAGES

37

16. PRICE CODE

17. SECURITY CLASSIFICATION

OF REPORT

Unclassified

18. SECURITY CLASSIFICATION

OF THIS PAGE

Unclassified

19. SECURITY CLASSIFICATION

OF ABSTRACT

Unclassified

20. LIMITATION OF ABSTRACT

NSN 7540-01-280-5500 Standard Form 298 (Rev. 2-89)

Prescribed by ANSI Std. 239-18

298-102
ii

METRIC/ENGLISH CONVERSION FACTORS

ENGLISH TO METRIC METRIC TO ENGLISH

LENGTH (APPROXIMATE) LENGTH (APPROXIMATE)

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 3 4 5

Inches

Centimeters 0 1 2 3 4 5 6 7 8 9 10 11 12 13

QUICK FAHRENHEIT - CELSIUS TEMPERATURE CONVERSIO

 -40° -22° -4° 14° 32° 50° 68° 86° 104° 122° 140° 158° 176° 194° 212°

 

°F

 °C -40° -30° -20° -10° 0° 10° 20° 30° 40° 50° 60° 70° 80° 90° 100°

For more exact and or other conversion factors, see NIST Miscellaneous Publication 286, Units of Weights and 

Measures. Price $2.50 SD Catalog No. C13 10286 Updated 6/17/98
iii

Contents

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

1. Introduction............................................................................................................................ 2

2. Test Requirements and Method ............................................................................................. 4

2.1 Car Preparation ................................................................................................................ 4

2.2 Pass/Fail Criteria.............................................................................................................. 5

2.3 Test Setup......................................................................................................................... 5

3. Instrumentation and Video..................................................................................................... 8

3.1 Definition of Coordinate Axes......................................................................................... 8

3.2 Longitudinal Strain Gage Locations................................................................................ 8

3.3 Load Cell........................................................................................................................ 10

3.4 String Potentiometer Measurements.............................................................................. 11

3.5 Supplemental Measurements......................................................................................... 14

3.6 Real-Time Photography................................................................................................. 14

3.7 Data Acquisition and Processing ................................................................................... 14

4. Test Results.......................................................................................................................... 16

4.1 Overall Length Criterion................................................................................................ 19

4.2 Strain Offset Criterion.................................................................................................... 21

5. Conclusions and Recommendations.................................................................................... 25

6. References............................................................................................................................ 26

Appendix A. Patch Details........................................................................................................... 27

Appendix B. String Potentiometer Locations, Polarities, and Exposed String Lengths............. 28

Abbreviations and Acronyms ....................................................................................................... 30
iv

Illustrations

Figure 1. Budd Pioneer Car 244 in Test Fixture............................................................................ 2

Figure 2. Fatigue Cracks in Side Sill ............................................................................................. 4

Figure 3. Cover Plate ..................................................................................................................... 5

Figure 4. Hydraulic Actuator at Load Application End................................................................. 6

Figure 5. Restraint System at Load Reaction End ......................................................................... 6

Figure 6. Target Load History ....................................................................................................... 7

Figure 7. Longitudinal Strain Gage Cross Section Locations........................................................ 9

Figure 8. Strain Gage Application Locations at Cross Sections 1 through 5 ................................ 9

Figure 9. Load Cell ...................................................................................................................... 11

Figure 10. VLL String Potentiometers at End/Center of Car ...................................................... 11

Figure 11. VLL String Potentiometers at Side Sills and Center Sill ........................................... 12

Figure 12. Camera Setup.............................................................................................................. 14

Figure 13. Load History during 800,000-Pound Load Cycle ...................................................... 16

Figure 14. Test Car under 800,000-Pound Compressive Load.................................................... 17

Figure 15. Peak Strains vs. Height on Car during the 800,000-Pound Load Cycle..................... 18

Figure 16. Location of Gage S2BRL Inside the Test Car............................................................ 19

Figure 17. Car 244 Length Reduction vs. Applied Load............................................................. 20

Figure 18. Car 244 Length Reduction on Expanded Scales ........................................................ 21

Figure 19. Temperature-Induced Strain Change of Unstrained Sample...................................... 22

Figure 20. Strain Offset vs. Temperature-Corrected Limits in Test 2......................................... 23

Figure 21. Non-Temperature-Corrected Strain Offsets in Test 1 ................................................ 23
v

Tables

Table 1. Test 1 Instrumentation Summary..................................................................................... 8

Table 2. Longitudinal Strain Gage Names at Cross Section 1..................................................... 10

Table 3. Longitudinal Strain Gage Names at Cross Section 6..................................................... 10

Table 4. String Potentiometers and Load Cell............................................................................. 13

Table 5. Additional Channel Descriptions................................................................................... 13

Table 6. Thermocouples............................................................................................................... 14

Table 7. Video Cameras and Views............................................................................................. 14
1

Executive Summary

The Federal Railroad Administration (FRA) has contracted with Transportation Technology 

Center, Inc. (TTCI) to perform a series of full-scale impact tests to provide the technical basis for 

rulemaking that will lead to improved crashworthiness and occupant protection for passenger 

railroad equipment. The series comprises the following: 

1. A quasi-static compressive end-load test at 800,000 pounds (lb), in accordance with 49 

CFR 238.203, using loads applied on the line of draft.

2. A repeat of Test 1 above to determine test vehicle readiness for Test 3. Preexisting 

fatigue cracks were discovered in Car 244 after Test 1. The fatigue cracks were repaired,

and Test 1 was repeated to ensure the integrity of the car. The test vehicle, Budd Pioneer 

Car 244, was determined to be suitable for Test 3.

3. A crippling load test to determine the ultimate strength of the car using loads applied 

through the crash energy management (CEM) system load paths.

This report summarizes Test 2, a quasi-static compressive end-load test at 800,000 lb conducted 

on January 19, 2011. The test was performed on Budd Pioneer Car 244, which has been 

modified to include a CEM system and has been assessed in full-scale impact tests six times 

previously. Test 2 results indicate that Car 244 is suitable for an additional test.
2

1. Introduction

FRA has a continuing applied research program to provide the technical basis for rulemaking 

that will lead to improved crashworthiness and occupant protection for passenger railroad 

equipment. The program includes both conventional equipment and innovative equipment that is 

being introduced more frequently into U.S. service. FRA has contracted with TTCI for support 

of full-scale test planning, test implementation, and processing of test data for this program. 

The present test, Test 2, is a repeat of Test 1. Before Test 2, the fatigue cracks that were 

discovered in Car 244 after Test 1 were repaired. Test 2 is being conducted to ensure that the car 

is acceptable for Test 3. The three-test series now planned for this car includes Tests 1 and 2, 

which have been conducted, and Test 3, which is scheduled for later in 2011.

1. Test 1. A static end-load test at 800,000 lb in accordance with 49 CFR 238.203 using 

loads applied on the line of draft.

2. Test 2. A repeat of Test 1 with repaired side sill cracks.

3. Test 3. A crippling-load test to determine the ultimate strength of the car using loads 

applied through the CEM system load paths.

The FRA program is currently focused on investigating alternative methods to assess the 

occupant volume strength of new rail cars, many of which contain CEM systems.

1

 A series of 

tests is to be performed on Budd Pioneer Car 244. This car has been modified to include a CEM 

system, and it has been tested in full-scale tests six times previously. In January 2010, this car 

was subjected to an 800,000-pound quasi-static end-load test, Test 1, similar to the present test.

2

Figure 1 shows Car 244 in the test fixture during Test 2.

Figure 1. Budd Pioneer Car 244 in Test Fixture
3

During the Car 244 inspection before Test 1, a small impact deformation was noted in the 

decorative trim covering the right side sill. The decorative trim was removed to permit the 

installation of strain gages for Test 1, but it was not noted that the side sill contained a 

deformation from the same impact that had dented the decorative trim. Nor was it observed that 

the side sill contained two fatigue cracks that had been covered by the decorative trim. The 

fatigue cracks were located in weld-heat-affected zones where brackets had been welded to the 

side sill to support under-car equipment.

During Test 1, the side-sill deformation was discovered, and it was observed to enlarge during 

the test. The enlargement was attributed to the aforementioned preexisting deformation, so it 

was not considered a test failure of the vehicle.

The fatigue cracks were not discovered until after Test 1. The fatigue cracks were loaded in 

compression during Test 1, so they had no effect on the test outcome.

After Test 1, the impact deformation was straightened and patches were welded in place over the 

fatigue cracks. Then Car 244 was retested in Test 2 to assure it was suitable for the higher 

compressive side-sill loads expected in Test 3. 

Companion computational work performed by the John A. Volpe National Transportation 

Systems Center (Volpe Center) for the three-test series has provided predictions of the vehicle’s 

response in the tests and substantial information that has been essential in test planning and 

preparation.1

This report summarizes Test 2, the static compressive end-load test at 800,000 lb, conducted 

January 19, 2011.
4

2. Test Requirements and Method

FRA provided the test requirements document for the subject test.

3 Test requirements were

developed jointly by FRA, Volpe Center, and TTCI.

2.1 Car Preparation

Two fatigue cracks were discovered in the right side sill (as viewed looking at the A-end from 

the B-end) after Test 1. Both cracks were adjacent to locations where supports had been welded 

to the inside of the sill. A patch was attached to keep the side sill in line during compression. 

Identical patches were applied to both sides of the car to maintain stiffness symmetry. Figure 2

shows the cracks on the side sill, and Figure 3 shows the patch in place over the cracks prior to 

welding. Appendix A contains a detailed drawing of the patch.

Figure 2. Fatigue Cracks in Side Sill
5

Figure 3. Cover Plate

The small impact deformation observed in the right side sill during Test 1 was straightened 

before Test 2.

2.2 Pass/Fail Criteria

As part of the planning activities for Test 2, Volpe Center and TTCI recommended three pass/fail 

criteria to assess the test results. The criteria are as follows:

1. The measurement of the overall length of the car shall return to within 0.050 inch (in) for 

the 800,000-pound load cycle.

2. Measured strain offsets shall remain below 1 percent, corrected for temperature.

3. There shall be no visible change in the car structure

2.3 Test Setup

Test 2 was conducted according to the load cycle and other requirements set forth in the Test 

Implementation Plan for 800,000-Pound Quasi-Static End Load Test, CEM Equipped Car, Test 

2, dated January 3, 2011. A hydraulic actuator applied the longitudinal test load to one end of 

the car (Figure 4), and a block reacted the load at the passive end of the vehicle (Figure 5).
6

Figure 4. Hydraulic Actuator at Load Application End

Figure 5. Restraint System at Load Reaction End

The test load was applied incrementally, as Figure 6 illustrates. A dwell period preceded and 

followed each target load and gave test personnel time to approach and inspect the car, examine 

data, or change hydraulic power units between cycles, if necessary. After the dwell period at the 

700,000-pound load, the load was reduced to slightly below 2,000 lb. After the 2,000-pound 

dwell period, the final 800,000-pound load cycle concluded the test sequence, as shown in Figure 

Hydraulic 

actuator
7

6. A single deviation from the Test Implementation Plan caused the load application rate for 

load cycles 3 through 5 to be greater than the anticipated 0.25 in/minute. The hydraulic power 

supply was changed between load cycles 2 and 3 because it was not producing the expected flow 

rate. As a result, the flow rate of the backup power supply produced a substantially higher load 

application rate. 

Figure 6. Target Load History
8

3. Instrumentation and Video

The car was extensively instrumented in this test. A load cell was placed between the actuator 

and the test car to measure the applied longitudinal load. Strain gages at 65 locations on 

longitudinal strength members provided information that indicated whether material elastic limits 

were exceeded during the test. Twenty-seven string potentiometers measured vehicle vertical, 

lateral, and longitudinal (VLL) deflections. Four high-definition video cameras and still video 

photography were used to document the pretest and posttest conditions of the vehicle and the 

conduct of the test. Table 1 summarizes the instrumentation count and types.

Table 1. Test 1 Instrumentation Summary

Type of Instrumentation Channel Count

Strain Gages (Longitudinal) 65

Load Cell 1

String Potentiometers 27

Thermocouples 3

Total Data Channels 92

Digital Video 4

3.1 Definition of Coordinate Axes

Positive x direction is longitudinal from the B-end toward the A-end of Car 244. Positive y

direction is left when the car was viewed from the B-end toward the A-end, and positive z is up. 

The origin of the reference frame is defined by x = 0 at the centerline of the B-end bolster, y = 0 

at car centerline, and z = 0 at top of rail (TOR) (see Figure 7). Locations of strain gages and 

string potentiometers were measured relative to these coordinate axes.

3.2 Longitudinal Strain Gage Locations

Longitudinal single-element strain gages were installed at six car cross sections. The cross

sections are numbered 1 through 6 starting near the center of the B-end bolster. Figure 7 shows 

the locations of the cross sections.

Figure 8 shows how the gages were applied at cross sections 1 through 5. At cross section 6,

only the belt line and side sill gages were applied.
9

Figure 7. Longitudinal Strain Gage Cross Section Locations

Figure 8. Strain Gage Application Locations at Cross Sections 1 through 5

B-End

X

Z

3 4 5 6

A-End

1 2

Top of Rail

Centerline of 

B-end Bolster

49”

177.9”

356.8”

535.6”

608.0”

694.2”
10

Table 2 contains the names and descriptions of strain gages mounted on longitudinal strength 

members at cross section 1. Strain gage names are similar at the remaining cross sections using 

numbers 2 through 5. For example, Gage S2SSL is located at cross section 2, side sill left. 

Table 2 also shows the gage heights above TOR.

Table 2. Longitudinal Strain Gage Names at Cross Section 1

Channel Name Sensor Description

Sensor Height 

from Top of Rail

(inches)

S1SSL Cross Section 1, Side Sill Left 47.6

S1BRL Cross Section 1, Belt Rail Left 78.0

S1RRL Cross Section 1, Roof Rail Left 111.5

S1PL Cross Section 1, Perlin Left 149.8

S1PR Cross Section 1, Perlin Right 149.8

S1RRR Cross Section 1, Roof Rail Right 111.5

S1BRR Cross Section 1, Belt Rail Right 78.0

S1SSR Cross Section 1, Side Sill Right 47.6

S1CSBL Cross Section 1, Center Sill Bottom Left 40.5

S1CSTL Cross Section 1, Center Sill Top Left 45.0

S1CSTR Cross Section 1, Center Sill Top Right 45.0

S1CSBR Cross Section 1, Center Sill Bottom Right 40.5

Cross section 6 is located 694.2 in from the B-end bolster centerline. At this location, 

longitudinal gages were installed on left and right side sills and the left and right belt rails only. 

Table 3 contains the names of the gages at cross section 6 and their heights above TOR.

Table 3. Longitudinal Strain Gage Names at Cross Section 6

Channel Name Sensor Description

Sensor Height 

from Top of Rail

(inches)

S6SSL Cross Section 6, Side Sill Left 47.6

S6BRL Cross Section 6, Belt Rail Left 78.0

S6BRR Cross Section 6, Belt Rail Right 78.0

S6SSR Cross Section 6, Side Sill Right 47.6

3.3 Load Cell

A 1,000,000-pound capacity load cell (Figure 9) was mounted at the actuator end of the car to 

measure applied load. The channel name of this load cell was LC1.
11

Figure 9. Load Cell

3.4 String Potentiometer Measurements

VLL string potentiometer arrays were used to measure displacements at nine locations on the 

car. Each VLL array was attached to the car at the same point. 

Two VLL arrays were installed at the loading location on the live end and the reaction location 

on the fixed end, as Figure 10 shows. This required a total of six string potentiometers.

Figure 10. VLL String Potentiometers at End/Center of Car

Four VLL arrays were installed at both ends on both side sills, as Figure 11 shows. This required 

12 string potentiometers. Three VLL arrays were installed on the center sill, as Figure 11 shows, 

and required nine string potentiometers. Table 4 contains the names of the string potentiometers 

and the load cell. After the Test Implementation Plan had been approved, the test team added 

several thermocouples and a strain gage to the vehicle’s instrumentation to assist in determining 
12

the effects of ambient temperature changes on strain gage readings. Table 5 contains the names 

and descriptions of the added channels.

Exposed string length of all string potentiometers was recorded before the test (Appendix B), and 

still photos of the attachments were taken. Positions of the sensors were recorded using the 

coordinate system in this report.

Figure 11. VLL String Potentiometers at Side Sills and Center Sill
13

Table 4. String Potentiometers and Load Cell

Channel Name Sensor Description

SPAX Loading End/Center – Longitudinal

SPAY Loading End/Center – Lateral

SPAZ Loading End/Center – Vertical

SPBX Reaction End/Center – Longitudinal

SPBY Reaction End/Center – Lateral

SPBZ Reaction End/Center – Vertical

SPSSALX Side Sill/Loading End/Left – Longitudinal

SPSSALY Side Sill/Loading End/Left – Lateral

SPSSALZ Side Sill/Loading End/Left – Vertical

SPSSARX Side Sill/Loading End/Right – Longitudinal

SPSSARY Side Sill/Loading End/Right – Lateral

SPSSARZ Side Sill/Loading End/Right – Vertical

SPSSBLX Side Sill/Reaction End/Left – Longitudinal

SPSSBLY Side Sill/Reaction End/Left – Lateral

SPSSBLZ Side Sill/Reaction End/Left – Vertical

SPSSBRX Side Sill/Reaction End/Right – Longitudinal

SPSSBRY Side Sill/Reaction End/Right – Lateral

SPSSBRZ Side Sill/Reaction End/Right – Vertical

SPCSAX Center Sill/Loading End – Longitudinal

SPCSAY Center Sill/Loading End – Lateral

SPCSAZ Center Sill/Loading End – Vertical

SPCSCX Center Sill/Center – Longitudinal

SPCSCY Center Sill/Center – Lateral

SPCSCZ Center Sill/Center – Vertical

SPCSBX Center Sill/Reaction End – Longitudinal

SPCSBY Center Sill/Reaction End – Lateral

SPCSBZ Center Sill/ Reaction End – Vertical

LC1 Load Cell

Additional channels are as follows:

Table 5. Additional Channel Descriptions

Channel Name Sensor Description

PR1 Pressure

THIGH Temperature on the car in high position

TLOW Temperature on the car in low position

TSPEC Temperature on the specimen

TAMB Temperature on the car in an ambient position

SSPEC Strain on the specimen
14

3.5 Supplemental Measurements

Thermocouples were installed on the roof, the side sill, and under the test car. Before the test, 

TTCI monitored strain gage and thermocouple responses on the unloaded car to determine strain 

gage response to temperature changes. Table 6 provides the names of the thermocouples.

Table 6. Thermocouples

Camera Location

TC1 Roof near S1PL

TC2 Side sill near S6SSR

TC3 Under test car

3.6 Real-Time Photography

Four high-definition video cameras recorded the test conduct. Table 7 provides the camera 

names and views.

Table 7. Video Cameras and Views

Camera View

HD camera 1 Isometric view of loading end

HD camera 2 Longitudinal view of car side to show camber deflection

HD camera 3 Isometric view of reaction end

HD camera 4 Side view of entire car

Figure 12 shows a schematic of the camera setup. 

Figure 12. Camera Setup

3.7 Data Acquisition and Processing

A MEGADAC 5414AC Data Acquisition System provided the analog to digital conversion, 

recording capability, and signal conditioning needed for the load cell, strains, and displacement 

transducers. The MEGADAC is a 16-bit system with user defined sample rates; the signal 

conditioning provides anti-aliasing filters, differential inputs, and resister calibrations to verify 

data integrity before and after testing.
15

Data was anti-alias filtered at 10 hertz (Hz) and recorded at 64 Hz. An uninterruptable power 

system was used in the event of power failure to ensure data integrity during the test. Strain gage 

channels were zeroed prior to initial load application.

All channels of data recorded by the MEGADAC acquisition system were decimated by a factor 

of 8 in postprocessing to reduce file size. The decimation resulted in an effective sample rate of 

8 Hz. Postprocessed data was stored digitally in engineering units and provided to FRA and

Volpe Center on external USB hard drives.

All recorded video files were transferred to external hard drives and provided to FRA and Volpe

Center. Video data was supplied in native uncompressed formats. The high-speed cameras used

.cine format. The high-definition video cameras used proprietary Sony® .m2t format. In 

addition to native formats, high-speed camera videos were converted to .avi format, and highdefinition videos were converted to .wmv format. One USB hard drive was provided to FRA 

and one to Volpe Center.
16

4. Test Results

Figure 13 shows the load history during the 800,000-pound cycle, which included a 4-minute 

dwell period. The maximum recorded load was approximately 820,000 lb. The load relaxed 

slightly and stabilized at approximately 800,000 lb toward the end of the dwell period.

Figure 13. Load History during 800,000-Pound Load Cycle

Figure 14 shows the test car during the dwell period at 800,000 lb. The camber of the car under 

load shows clearly relative to the red reference line. Waves that formed in the skin of the car are 

apparent in the photograph. The waves appear as the alternating light and dark vertical bands 

under the windows.
17

Figure 14. Test Car under 800,000-Pound Compressive Load

When the car was loaded in compression, strains in the center sill and other lower areas of the 

car were compressive. Strains in the roof perlins were tensile. To visualize the strain variations 

in the car from bottom (compression) to top (tension), TTCI engineers plotted the maximum 

values of strains in all the carbody gages versus percentage of car height, where the zero height 

datum is at the lowest gages on the center sill. Figure 15 shows peak strains during the 800,000-

pound load cycle. The peak strains cluster fairly well along a straight line, except for those at 

belt rail, where the scatter is substantial. The linear approximation crosses the zero-strain axis 

near the roof rail, where all strain gages registered small values.

The strain plotted in Figure 15 for gage S2BRL having a value of approximately –3,100 

microstrain shows as the outlying brown square at cross section 2. Becausee Figure 15 shows 

data from all the carbody strain gages during the peak loading cycle, it is clear that all other peak 

strains are substantially smaller. 
18

Figure 15. Peak Strains versus Height on Car during the 800,000-Pound Load Cycle

The –3,100 microstrain corresponds to a stress of approximately –90,000 pounds per square inch 

(psi), which TTCI understands to be below the minimum yield strength of the stainless steel belt 

rail material. The strain readings from gage S2BRL were substantially higher than other strains 

recorded during the test. Gage S2BRL is on the belt rail adjacent to a section that is bent inward 

toward the center of the car. When the car compresses under load, that section deflects inward 

and puts the gage into additional compression. Figure 16 shows the strain gage inside the car. 

(Note: The gage label shows the name from a previous designation. The photograph shows 

gage S2BRL covered with black protective material). The mounting location of this strain gage 

near a bent section on the belt rail accounts for the uncharacteristically high strain readings.
19

Figure 16. Location of Gage S2BRL inside the Test Car

The following subsections discuss test results in relation to the pass/fail criteria in 

subsection 2.2.

4.1 Overall Length Criterion

Figure 17 shows car-length reduction versus applied load for load cycles 1 and 5, the 200,000-

and 800,000-pound load cycles. In load cycle 5, substantial hysteresis separates the loading and 

unloading portions of the cycle. At the beginning of the unloading cycle, the order of 

20,000 lb of load change occurs before appreciable change in car length occurs. Both the 

hysteresis and the varying slope of the length versus load curves constitute nonlinear behavior of 

the load-elongation response of the car. 
20

-100 0 100 200 300 400 500 600 700 800 900

-0.5

0

0.5

1

1.5

2

2.5

Load (kip)

Overall Length Reduction (inch)

Load Cycle 1

Load Cycle 5

Figure 17. Car 244 Length Reduction versus Applied Load

The overall length criterion was evaluated for the entire test period rather than for the 800,000-

pound load cycle, as required by criterion 1. The load at the beginning of the 800,000-pound 

load cycle was not the same as the load at the end of the cycle, so any change in length would 

have partially resulted from the change in load. 

The test duration includes the zero load condition before application of the first load cycle 

through the zero load condition after conclusion of the load cycle 5. Figure 18 shows another 

view of Figure 17 with expanded scales near the origin. In Figure 18, it is clear that the overall 

change in car length is less than 0.05 in. The recorded value of car-length reduction over the test 

is 0.0045 in, which is well within the pass/fail criterion.

In Test 1, on January 20, 2010, the car-length reduction was 0.011 in, which is also within the 

overall length pass/fail criterion limit.

In Figure 18, the nonconstant slopes of the load-elongation curves are apparent. Car 244 emitted 

sounds that could be described as creeks, groans, and pops during both loading and unloading. 

The acoustic emissions are consistent with localized stick-slip behavior within the car structure. 

The car structure includes both welded and riveted connections. 
21

0 50 100 150 200

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Load (kip)

Overall Length Reduction (inch)

Load Cycle 1

Load Cycle 5

Figure 18. Car 244 Length Reduction on Expanded Scales

4.2 Strain Offset Criterion

Pass/fail criterion No. 2 requires the readings of all strain gages to exhibit no greater indicated 

strain change than 1 percent of the yield strain of the materials on which the gages are installed 

from the beginning to the end of the test. The beginning to the end of the test is taken to include 

the zero load condition before application of the first load cycle through the zero load condition 

after conclusion of the fifth load cycle.

All structural materials on Car 244 have a yield strength of at least 75,000 psi. The yield strain 

in a tensile test is related to the yield stress by

E

y

y

σ

ε =

For 75,000 psi yield strength and 29 × 106 psi elastic modulus, the yield strain is

6

6 2,600 10

29 10

75,000 − ≅ ×

×

ε y =

So, 1 percent of the yield strain is approximately 26 microstrain. Figure 19 shows the 

temperature-induced changes of indicated strain on an unstressed sample of side sill material 

suspended under the center of the car during the test. The temperature of the sample dropped by 

approximately 2 oF during the test.
22

The total change in indicated strain between the beginning of the first load cycle and the end of 

the last load cycle was –9 microstrain. The lower limit of strain offset is therefore 

microstrain. The upper limit of strain offset is microstrain.

Figure 20 shows offsets for all 64 strain channels during Test 2. Nearly half the strain offsets fall 

below the lower limit of 1 percent, corrected for temperature. The minimum strain offset is 

–66 microstrain. This strain offset occurred on channel 20, S2BRR. The name code translates to 

strain at cross section 2, belt rail, and right side of car as described in the Test Implementation 

Plan. The maximum magnitude strain was approximately –1,400 microstrain, which corresponds 

to a compressive stress of approximately 42,000 psi, well below the minimum yield strength of 

instrumented members. The –66 microstrain offset corresponds to a compressive stress of 

approximately 1,900 psi. The belt rail has a cross-sectional area of approximately 0.25 in2

, so 

the corresponding compressive force is approximately 500 lb if the strain is uniform.

For comparison purposes, Figure 21 shows strain offsets for the same 64 strain channels during 

Test 1, which was conducted a year earlier. These strain offsets are not temperature 

compensated because the zero-strain material reference sample was not used in that test. 

Ambient temperature increased during Test 1 by approximately 5 oF. Test 1 strain offsets meet a 

strain offset criterion set at 4 percent of yield strain without temperature compensation. 

Temperature compensation is important when judgments are being made based on small changes 

in strain levels because indicated strain levels change with both ambient temperature and actual 

strain. 

0 50 100 150 200 250 300 350 400 450

-10

-8

-6

-4

-2

0

2

4

Time (s)

Strain Change (microstrain)

Load Cycle 1

Load Cycle 5

Figure 19. Temperature-Induced Strain Change of Unstrained Sample
23

0 10 20 30 40 50 60 70

-80

-60

-40

-20

0

20

40

60

80

100

Strain Channel Number

Total Strain Offsets over Test

Red lines are limits based on 1% of yield strain

Figure 20. Strain Offset versus Temperature-Corrected Limits in Test 2

0 10 20 30 40 50 60 70

-80

-60

-40

-20

0

20

40

60

80

100

Strain Channel Number

Total Strain Offsets over Test

Figure 21. Non-Temperature-Corrected Strain Offsets in Test 1
24

4.3 Visual Observation Criterion

Car 244 was inspected visually at the test site immediately after the test and again the following 

day when the car was positioned over a pit to facilitate inspection of the center sill and side sills. 

No permanent deformation was observed. 
25

5. Conclusions and Recommendations

Car 244 passed the overall length and visual inspection criteria established prior to Test 2. It did 

not pass the strain offset criterion. The maximum strain reading on the strain gage having the 

greatest strain offset shows that the corresponding stress was below the yield stress of the belt 

rail material.

Test data shows that strain offsets observed in the test do not correlate well with the magnitude 

of strain for a given strain gage location. Strain offsets over each load cycle do not correlate well 

with the magnitude of the applied loads.

Based upon these test results, TTCI recommends the following:

• The overall length criterion of 0.05-inch change in car length demonstrated that the car 

had a negligibly small change in length over both Test 1 and Test 2. The overall length 

criterion should be retained. For general use, the allowable length change should be 

expressed as a percentage of car length.

• Visual inspection of the car revealed no changes in car structure. Visual inspection is 

important because not all areas on the car are monitored by instrumentation. The visual 

inspection criterion should be retained.

• The strain offset criterion did not prove to be effective when applied to Test 1 or Test 2. 

Instead, it is recommended that the yield criterion require the maximum magnitude of 

measured strain to be less than the yield strain of the material. It is noted that this 

criterion already appears in Option A of the occupant volume integrity compliance 

criteria discussed in the September 2010 Draft Rail Safety Advisory Committee Report

titled Technical Criteria and Procedures for Evaluating the Crashworthiness and 

Occupant Protection Performance of Alternatively Designed Passenger Rail Equipment 

for Use in Tier I Service.

4

• When the maximum strain criterion above replaces the strain offset criterion, Car 244 

passes the acceptance criteria. TTCI concludes that the vehicle is acceptable for the 

crippling load test, Test 3.
26

6. References

1. Carolan, M., and Muhlanger, M. P. “Strategy for alternative occupant volume testing.” In 

proceedings of the ASME 2009 Rail Transportation Division Fall Conference. 20–21 Oct. 

2009, Fort Worth, TX. New York, NY: American Society of Mechanical Engineers.

2. Fries, R. H., and Anankitpaiboon, S. “800,000-Pound quasi-static end-load test of crash 

energy management equipped car, test 1.” U.S. Department of Transportation Report No. 

DOT/FRA/ORD-10/12. 2010 Nov. Washington, DC: Office of Railroad Policy and 

Development, Federal Railroad Administration. 

http://www.fra.dot.gov/rpd/downloads/TR_800K_pound_test_102910.pdf.

3. Muhlanger, M., and Carolan, M. “Test requirements: 800 kip Occupant Volume Strength 

Tests.” Prepared for Federal Railroad Administration Equipment Safety Research Program. 

2009 Oct. and revisions. Washington, DC: U.S. Department of Transportation.

4. Carolan, M., Llana, P., and Tyrell, D. “Technical criteria and procedures for evaluating the 

crashworthiness and occupant protection performance of alternatively designed passenger 

rail equipment for use in tier I service.” DOT/FRA/ORD draft report. 2010 Sept. 16. 

Washington, DC: Railroad Safety Advisory Committee/Passenger Safety Working 

Group/Engineering Task Force. U.S. Department of Transportation, Federal Railroad 

Administration, Office of Research and Development.
27

Appendix A. 

Patch Details
28

Appendix B.

String Potentiometer Locations, Polarities, and 

Exposed String Lengths

A-end

B-end
29

String Potentiometer Sign Conventions

Location String 

Potentiometer

Exposed String 

Length (inches)

1 Vertical 28 1/2

1 Lateral 38 3/16

1 Longitudinal 47 13/16

2 Vertical 15 1/8

2 Lateral 54

2 Longitudinal 56 3/8

3 Vertical 29 1/2

3 Lateral 39 5/8

3 Longitudinal 56 1/4

4 Vertical 16 1/2

4 Lateral 82 3/16

4 Longitudinal 48 3/16

5 Vertical 15 1/16

5 Lateral 80 3/8

5 Longitudinal 64 13/16

6 Vertical 20 13/16

6 Lateral 81 9/16

6 Longitudinal 53 1/8

7 Vertical 33 1/8

7 Lateral 36 15/16

7 Longitudinal 42 3/8

8 Vertical 18 15/16

8 Lateral 60 1/2

8 Longitudinal 22 3/8

9 Vertical 32 7/16

9 Lateral 40 1/8

9 Longitudinal 46 3/16
30

Abbreviations and Acronyms

oF

CEM

degrees Fahrenheit

crash energy management

FRA Federal Railroad Administration

TOR top of rail

TTCI Transportation Technology Center, Inc.

VLL vertical, lateral, and longitudinal