FOREWORD

This report documents analysis ofthe continuously reinforced concrete (CRC) pavement test

sections under study in the General Pavement Studies 5 (GPS-5) experiment ofthe Long Term

Pavement Performance Program. Limitations ofthe data available when this work was

undertaken precluded the production of definitive findings. However, the work does show that

CRe pavements can perform well.

-7£~ T. Paul Teng, P.E. (I \

Director

Office oflnfms.tructure

Research and Devdopmz;nt

NOTICE

This document is disseminated under the sponsorship ofthe Department of Transportation in the

interest ofinformation exchange. The United States Government assumes no liability for its

contents or use thereof. This report does not constitute a standard, specification, or regulation.

The United States Government does not endorse products or manufacturers. Trademarks or

manufacturers' names appear herein only because they are considered essential to the object of

this document.

PROTECTED UNDER INTERNATIONAL COPYRIGHT

ALL RIGHTS RESERVED.

NATIONAL TECHNICAL INFORMATION SERVICE

U.S. DEPARTMENT OF COMMERCE
Technical Report Documentation Page \1 1. Report No.

1

1.'1~'lll' 1111111'''\1\ 11\'" 11\ I 3. Recipient's Catalog No.

FHWA-RD-99-086 P'd99 -162 77H

4. Title and Subtitle 5. Report Date

PRELIMINARY EVALUATION OF LTPP Julv 1999

CONTINUOUSLY REINFORCED CONCRETE (CRC) 6. Performing Organization Code

PAVEMENT TEST SECTIONS

7. Author(s) 8. Performing Organization Report No.

Shiraz D. Tayabji, Olga Selezneva, and Y. Jane Jiang

9. Performing Organization Name and Address 10. Work Unit No. (TRAIS)

ERES Consultants, Inc. C6B

9030 Red Branch Road, Suite 210 11. Contract or Grant No.

Columbia, Maryland 21045 DTFH61-95-C-00028

12. Sponsoring Agency Name and Address 13. Type of Report and Period Covered

Office of Infrastructure Research & Development Final Report

Federal Highway Administration Feb. 1995 - Oct 1998

6300 Georgetown Pike

14. Sponsoring Agency Code McLean, Virginia 22101-2296

15. Supplementary Notes

Contracting Officer's Technical Representative (COTR): Cheryl Allen Richter

Consultant: Dr. Dan G. Zollinger, P.E. served as technical consultant

16. Abstract

As part of the study reported here, analysis of data from the LTPP GPS-5 test sections was

conducted to identify factors that influence long-term crack spacing in continuously reinforced

concrete (CRe) pavements and to determine the effect of crack spacing on pavement performance.

Data from the 85 test sections from the GPS-5 experiment were analyzed.

Due to the limitations of the available data and the lack of certain key data, the study was not able

to produce definitive findings on factors that affect long-term crack spacing and CRC pavement

performance. Lack of early-age cracking due to ambient weather conditions at the time of

construction will continue to limit the value of GPS-5 to produce meaningful data on factors

affecting early-age cracking. Continued monitoring of GPS-5 sites and subsequent data analysis

should yield information on how CRC pavement cracking and performance changes with time,

loading, and other factors. It is expected that as additional data from the GPS-5 experiment become

available, it will be possible to perform more in-depth analysis of the test data to derive definitive

results. Results to date, as presented in this report, do indicate that CRC pavements have the

potential to provide long-term, low-maintenance service life as evidenced by the many wellperforming sections in the LTPP GPS-5 experiment.

17. Key Words 18. Distribution Statement

Concrete pavements, continuously reinforced No restrictions. This document is available to

concrete pavement, CRCP, LTPP, pavement the public through the National Technical

distress, pavement performance, pavement testing, Information Service, Springfield, VA 22161.

punchouts.

19. Security Classification (of this report) 20. Security Classification (of this page) 21. No. of Pages 22. Price

Unclassified Unclassified 61

Form DOT F 1700.7 (8-72) Reproduction of completed page authorized
• I •

APPROXIMATE CONVERSIONS TO SI UNITS APPROXIMATE CONVERSIONS F

Symbol When You Know Multiply By To Find Symbol Symbol When You Know MUltiply By 

LENGTH LENGTH

in inches 25.4 millimeters mm mm millimeters 0.039 

ft feet 0.305 meters m m meters 3.28 

yd yards 0.914 meters m m meters 1.09 

mi miles 1.61 kilometers km km kilometers 0.621 

AREA AREA

in2 square inches 645.2 square millimeters mm2 mm2 square millimeters 0.0016 

ft2 square feet 0.093 square meters m2 m2 square meters 10.764 

yd2 square yards 0.836 square meters m2 m2 square meters 1.195 

ac acres 0.405 hectares ha ha hectares 2.47 

mi2 square miles 2.59 square kilometers km2 km2 square kilometers 0.386 

VOLUME VOLUME

fI oz fluidounces 29.57 milliliters mL mL milliliters 0.034 

_.

III gal gallons 3.785 liters L L liters 0.264 

_.

ft" cubic feet 0.028 cubic meters m3 m3 cubic meters 35.71 

yd3 cubic yards 0.765 cubic meters m3 m3 cubic meters 1.307 

NOTE: Volumes greater than 1000 I shall be shown in m3•

MASS MASS

oz ounces 28.35 grams g g grams 0.035 

Ib pounds 0.454 kilograms kg kg kilograms 2.202 

T short tons (2000 Ib) 0.907 megagrams Mg Mg megagrams 1.103 

(or "metric ton") (or "to) (or "to) (or "metric ton")

TEMPERATURE (exact) TEMPERATURE (exa

of Fahrenheit 5(F-32)/9 Celcius °C °C Celcius 1.8C + 32 

temperature or (F-32)/1.8 temperature temperature 

ILLUMINATION ILLUMINATION

fc foot-candles 10.76 lux Ix Ix lux 0.0929 

fI foot-Lamberts 3.426 candelalm2 cdlm2 cdlm2 candelalm2 0.2919 

FORCE and PRESSURE or STRESS FORCE and PRESSURE or 

Ibf poundforce 4.45 newtons N N newtons 0.225 

Ibflin2 poundforce per 6.89 kilopascals kPa kPa kilopascals 0.145 

square inch 

• SI is the symbol for the International System of Units. Appropriate 

rounding should be made to comply with Section 4 of ASTM E380.
TABLE OF CONTENTS

CHAPTER 1. INTRODUCTION 1

Scope of Work 2

Report Organization 2

CHAPTER 2. GPS-5 DATA CHARACTERISTICS 3

Inventory and Monitoring Data Summary 7

Climatic Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Traffic Data 18

Summary 24

CHAPTER 3. EVALUATION OF CRACK SPACING DATA 25

Introduction 25

Bi-Variate Plots 25

Effect ofCracking on Ride 33

Effect ofCrack Spacing on Deflections 34

Summary 34

CHAPTER 4. ANALYSIS OF WELL AND POORLY PERFORMING SECTIONS 37

Summary 51

CHAPTER 5. SUMMARY AND RECOMMENDATIONS 53

REFERENCES 55

111
LIST OF FIGURES

Fieure Paee

1 Age as oflatest distress survey 14

2 Age as ofDecember 31, 1997 14

3 Design slab thickness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

4 Design percent longitudinal steel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

5 Depth to longitudinal reinforcement 16

6 Longitudinal bar spacing 16

7 Transverse bar spacing 17

8 Annual freezing index summary 19

9 Annual precipitation summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

10 Average daily temperature range 20

11 Cumulative ESAL summary 21

12 Average IRI summary 21

13 Average crack spacing 23

14 Typical crack spacing distribution plot for a CRC pavement 26

15 Typical plot ofASCFC for a CRC pavement 26

16 Crack spacing versus age 27

17 Crack spacing versus cumulative ESALs 28

18 Crack spacing versus slab thickness 28

19 Crack spacing versus concrete modulus of elasticity, Es1ab ••••••••••••••••••••••• 29

20 Crack spacing versus percent longitudinal steel 29

21 Crack spacing versus percent longitudinal steel (age < 10 years) 30

22 Crack spacing versus percent longitudinal steel (age> 10 years) 30

23 Crack spacing versus depth to longitudinal reinforcement 31

24 Crack spacing versus annual air freezing index 31

25 Crack spacing versus annual precipitation 32

26 Crack spacing versus average daily temperature range 32

27 Crack spacing versus longitudinal bar spacing 33

28 Effect of crack spacing on IRI 34

29 Average load transfer efficiency at cracks versus crack spacing 35

30 Ratio ofmaximum edge and interior deflections versus crack spacing 35

31 Comparison of design percent longitudinal steel. 41

32 Comparison of depth to reinforcement. 41

33 Comparison oflongitudinal bar spacing 42

34 Comparison oftransverse bar spacing 42

35 Comparison ofslab thickness 43

36 Comparison of concrete modulus of elasticity as tested, Es1ab ••••••••••••••••••••• 43

37 Comparison of base thickness. . 44

38 Comparison of base modulus of elasticity, Ebase, as backcalculated 44

39 Comparison ofsubgrade k-value as backcalculated. . 45

IV
LIST OF FIGURES (Continued)

Fie;ure Pae;e

40 Comparison of annual air freeze index. . 45

41 Comparison of annual precipitation. . 46

42 Comparison of daily temperature range 46

43 Comparison of crack spacing 47

44 Comparison ofIRI values 47

45 Comparison of age. . 48

46 Effect of climatic region. . 48

47 Effect ofreinforcement placementtype 49

48 Effect of base type 49

49 Effect ofsubgrade type. . 50

50 Effect ofshoulder type. . 50

v
LIST OF TABLES

1 Distribution of GPS-5 sections by climatic regions 3

2 Distribution of GPS-5 sections by state. . 4

3 List of sections 5

4 List of overlaid sections. . 7

5 GPS-5 data summary 8

6 Percentage distribution ofAASHTO subgrade types for GPS-5 sections 18

7 Severity oftransverse cracking 22

8 Criteria for identification of well and poorly performing sections 37

9 Lists of well performing sections and complementary data for sections 39

10 Lists of poorly performing sections and complementary data for sections 40

VI
CHAPTER 1. INTRODUCTION

A continuously reinforced concrete (CRC) pavement is a portland cement concrete (PCC)

pavement with continuous longitudinal steel reinforcement and no intermediate expansion or

contraction joints. The continuous joint-free length ofCRC pavement can extend to several

miles (kilometers), with breaks provided only at structures. CRC pavements develop a transverse

cracking pattern, with cracks generally spaced at about 0.6 to 1.8 m (2 to 6 ft). The cracking

pattern is governed by the environmental conditions at the time of construction, the amount of

steel reinforcement, and concrete strength. The steel reinforcement restrains the opening ofthe

cracks. Also, the higher the amount ofsteel reinforcement used, the more closely spaced the

cracks will be. Most ofthe cracks develop shortly after concrete placement; however, additional

cracking may develop over several years as a result of continued drying shrinkage of concrete,

temperature variations, and traffic loading.

A major concern with CRC pavement is punchout distress. The definition of punchout

distress is the area enclosed by two closely spaced (usually less than 0.6 m [2 ftD transverse

cracks, a short longitudinal crack, and the edge ofthe pavement or a longitudinal joint. It also

includes "Y" cracks that exhibit spalling, breakup, and faulting. The punchout distress is related

to crack spacing, pavement thickness, poor foundation support, and heavy truck loadings. The

repair of punchout distress typically consists offull-depth PCC patches. With time and as the

number offull-depth patches increases, the pavement may be resurfaced with asphalt concrete

(AC) or PCC, or it may be reconstructed. It should be noted that CRC pavements with smaller

crack spacing (e.g., 0.6 m [2 ftD do exhibit good performance provided the support condition is

very good. Other distresses associated with punchouts include spalling along transverse cracks

and faulting at cracks. Other leading causes ofCRC failure are wide (and spalled) transverse

cracks due to steel rupture and spalling of concrete due to steel corrosion in the presence of heavy

deicing salt applications in the northern states.

Over the years, many studies have been conducted to explore the behavior and

performance ofCRC pavements. Many ofthese studies have focused on the mechanism of

transverse crack development. Mechanistic procedures have been developed to predict crack

spacing (e.g., CRCP-7(1»); however, these procedures require a fairly accurate knowledge of

ambient climatic conditions and concrete's early-age properties. Other studies have focused on

understanding the mechanism of punchout development. For this case also, mechanistic

procedures have been proposed (e.g., Zollinger and Barenberg(2»). However, these mechanisticbased procedures require a fairly detailed knowledge oftraffic loading (by specific axle loading)

and climatic conditions (for computing curling and warping stresses and changes in the shape of

the pavement as a result oftemperature variation within the concrete), especially climatic

(ambient) conditions during the first few days after concrete placement.

The availability ofthe General Pavement Studies (GPS)-5 CRC pavement test sections in

the Long Term Pavement Performance (LTPP) program provides an opportunity to evaluate

factors affecting the cracking ofCRC pavements and to identify how the cracking pattern and

other CRC pavement attributes affect CRC pavement behavior under traffic loading. As part of a

Federal Highway Administration (FHWA)-sponsored project, work was undertaken to use test

1
data from the LTPP program to study the transverse cracking pattern at the GPS-5 test sections

and to evaluate the structural behavior ofthese sections.

As part ofthe LTPP program, an extensive data collection effort has been underway since

about 1989. These data types are classified within the LTPP program as follows:

1. Inventory

2. Materials Testing

3. Climatic

4. Monitoring

5. Traffic

6. Seasonal

In addition, as appropriate, maintenance, rehabilitation, and construction data are also

collected.

Scope of Work

The overall objective ofthe study reported here was to evaluate key factors affecting the

development of crack spacing in CRC pavements and to determine the effect, if any, ofthe crack

spacing on the structural response as well as the performance ofthe pavements. Because oflack

of construction-time ambient condition data, no attempt was made to verify/validate mechanisticbased crack spacing development models such as CRCP-7 and TTICRCP. As part ofthe study,

an attempt was also made to evaluate the structural performance ofthe CRC pavements using

procedures developed by Professor Dan Zollinger ofthe Texas Transportation Institute (TTl).

Report Organization

Chapter 1 provides the background for the study. Chapter 2 provides a summary ofthe

GPS-5 test section characteristics. Chapter 3 provides an evaluation ofthe crack spacing data.

Chapter 4 presents an analysis ofwell and poorly performing test sections and chapter 5 presents

a summary offindings and provides a discussion on improvements needed to be made to further

advance the CRC pavement technology using LTPP data.

2
CHAPTER 2. GPS-5 DATA CHARACTERISTICS

The LTPP data used in this report were obtained initially from the Information

Management System (IMS) during February 1996 (IMS Release 6.0 data). These data were

subsequently supplemented using DataPave97, version 1.0. The total number of GPS-5 sections

available through DataPave97 was 85, with sections located in 4 climatic regions and 29 different

states, as presented in tables 1 and 2. Texas has the largest number oftest sections, which

constitute 22 percent of all GPS-5 sections. A list ofthe 85 test sections is given in table 3. Each

test section is also identified with a reference number (from 1 to 85) to facilitate the plotting of

charts presented later. In subsequent discussion and in tables and charts, the test sections are

identified by these reference numbers. At the time ofDataPave97's release (data as of October

1997), 9 ofthe 85 sections were overlaid, as indicated in table 4. For the overlaid sections, only

data for the period prior to overlay were used in this study.

The LTPP database for the GPS-5 sections consists ofthe following modules: inventory,

environment, material testing, monitoring, and traffic. Each module contains data collected and

stored at different times for different sections. The monitoring data used in the analysis are from

the latest measurements available for each section for each data type.

Table 1. Distribution of GPS-5 sections by climatic regions.

Climatic Region No. of Sections

Wet-Freeze Region 40

Wet-No Freeze Region 35

Dry-Freeze Region 6

Dry-No Freeze Region 4

Total 85

3
Table 2. Distribution of GPS-5 sections by state.

State State ID Number of GPS-5 Sections

AL 01 2

AZ 04 1

AR 05 2

CA 06 1

CT 09 1

DE 10 2

GA 13 1

ID 16 1

IL 17 8

IN 18 3

IA 19 3

MD 24 1

MI 26 1

MN 27 1

MS 28 5

MO 29 1

NE 31 1

NC 37 3

ND 38 1

OH 39 2

OK 40 3

OR 41 6

PA 42 3

SC 45 3

SD 46 3

TX 48 19

VA 51 4

WV 54 1

WI 55 2

TOTAL 29 States 85 Sections

4
Table 3. List ofsections.

Reference No. Section Current Status. Climatic Region.. Open-to-Traffic Date

1 013998 WNF 03/01174

2 015008 WNF 12/01177

3 047079 08/01189

4 055803 WNF 07/01173

5 055805 WNF 11101175

6 067455 ONF 12/01171

7 095001 WF 11/01181

8 105004 WF 06/01177

9 105005 WF 06/01171

10 135023 WNF 06/01174

11 165025 OF 09/01172

12 175020 WF 10101/86

13 175151 78 10101166

14 175843 WF 09/01182

15 175849 WF 11101171

16 175854 WF 01101182

17 175869 WF 12/01179

18 175908 WF 04/01171

19 179267 WF 10101/66

20 185022 78 WF 01101172

21 185043 WF 01101/69

22 185518 78 WF 12/01170

23 195042 WF 12/01175

24 195046 WF 11101175

25 199116 78 WF 08/01172

26 245807 WF 06101/90

27 265363 WF 12/01176

28 275076 78 WF 10/01170

29 283099 78 WNF 11101170

30 285006 WNF 04/01179

31 285025 WNF 07/01177

32 285803 WF 09/01179

33 285805 WNF 06101175

34 295047 WF 07/01172

35 315052 WF 12/01/69

36 375037 WNF 10101172

37 375826 78 WF 06101177

38 375827 WF 03/01173

39 385002 WF 11/01173

40 395003 WF 09/01/88

41 395010 78 WF 07/01175

42 404158 WF 06101189

43 404166 WNF 06101190

44 405021 WF 10101187

45 415005 WNF 10101185

5
Table 3. List ofsections (continued).

Reference No. Section Current Status. Climatic Region.. Open-to-Traffic Date

46 415006 DF 06/01173

47 415008 DF 06/01172

48 415021 WNF 07/01186

49 415022 WNF 10/01184

50 417081 DF 09/01188

51 421598 WF 01101/75

52 421617 7B WF 06/01172

53 425020 WF 05/01180

54 455017 WNF 03/01/79

55 455034 WNF 06/01/75

56 455035 WNF 11101/75

57 465020 DF 08/01/73

58 465025 DF 11101/74

59 465040 WF 07/01163

60 483719 WNF 01101165

61 483779 DNF 06/01/78

62 485024 WNF 01101182

63 485026 WNF 06/01188

64 485035 WNF 09/01/79

65 485154 WNF 08/01/71

66 485274 WNF 03/01/73

67 485278 DNF 06/01/75

68 485283 WNF 04/01188

69 485284 WNF 03/01188

70 485287 WNF 08/01/73

71 485301 WNF 02/01/82

72 485310 WNF 07/01187

73 485317 WNF 04/01/82

74 485323 WF 10/01180

75 485328 WNF 09/01/75

76 485334 WF 04/01/70

77 485335 WF 10/01180

78 485336 WF 12/01186

79 512564 WNF 02/01169

80 515008 WNF 08/01177

81 515009 WNF 06/01/80

82 515010 WNF 10/01188

83 545007 taken out ofstudy WF 06/01/77

84 555037 WF 11/01/73

85 555040 WF 11101/80

••

Note:

7B = GPS Experiment 7B

WF = wet-freeze region, WNF = wet-no freeze region, DF = dry-freeze region, DNF =

dry-no freeze region.

Data as of October 1997.

6
Table 4. List of overlaid sections.

State State ID SHRPID Year Constructed Current Status Year Overlaid

IL 17 5151 1966 GPS-7B Section 1990

IN 18 5022 1972 GPS-7B Section 1993

IN 18 5518 1970 GPS-7B Section 1993

IA 19 9116 1972 GPS-7B Section 1989

MN 27 5076 1970 GPS-7B Section 1990

MS 28 3099 1970 GPS-7B Section 1992

NC 37 5826 1977 GPS-7B Section 1995

OH 39 5010 1975 GPS-7B Section 1990

PA 42 1617 1972 GPS-7B Section 1991

Inventory and Monitoring Data Summary

The inventory and monitoring data available for GPS-5 sections are summarized in table

5. The characteristics ofthe key data are discussed next.

Age

The age for the GPS-5 sections was determined as the difference between the date ofthe

last crack survey and the traffic opening date. Based on this calculation, the age ofthe test

sections ranged from 1 to 30 years. The age summary is given in figure 1. Also, another age

calculation was made as ofDecember 31, 1997, as presented in figure 2. As ofDecember 31,

1997, there were 59 sections that were 15 years of age or older and 42 ofthese sections were 20

years of age or older. With respect to the age at the time ofthe last distress survey, there were 23

sections that were 20 years of age or older.

Slab Design Data

The pavement slab design data include mean slab thickness, design percent oflongitudinal

steel, depth to reinforcement, spacing oflongitudinal and transverse reinforcing bars, and

reinforcement placement method. Design parameter summaries are given in table 5 and presented

in figures 3 through 7. The following observations are made:

1. Fifty sections had 203-mm-thick slabs, 18 sections had 228-mm-thick slabs, and

10 sections had 254-mm-thick slabs. Only five sections had slabs thicker than 270

mm and only three sections had slabs thinner than 200 mm. This represents a very

biased sample.

7
00

Table 5. GPS-5 data summary.

Least

Average

Crack

Spacing

from Date

Manual Manual PADIAS PADIAS Manual Tested for

Manual Total High Average PADIAS Total High Average and Least 

Manual Total Severity Crack PADIAS Total Severity Crack PADIAS Average Open-to- A

Section Current Climatic Survey Trans. Trans. Spacing, Survey Trans. Trans. Spacing, surveys, Crack Traffic T

No. Section ID Status Region Date Crack No. Crack No. m Date Crack No. Crack No. m m Spacing Date 

1 01-3998 WN 04/16/90 61 0 2.50 2.50 04/16/90 03/01174 

2 01-5008 WN 02112190 118 0 1.29 1.29 02/12/90 12101177 

304-7079 DN 01115/91 83 0 1.84 1.84 01/15/91 08/01/89 

4 05-5803 WN 11129/94 159 0 0.96 02127/91 153 0 1.00 0.96 11/29/94 07/01173 

505-5805 WN 11/28/94 213 0 0.72 11/14/89 123 0 1.24 0.72 11/28/94 11/01175 

6 06-7455 DN 12117/91 221 0 0.69 0.69 12/17/91 12101171 

7 09-5001 WF 04/09/96 115 1 1.33 09/04/90 99 0 1.54 1.33 04/09/96 11/01/81 

8 10-5004 WF 03/16/93 113 0 1.35 03/21/91 52 0 2.93 1.35 03/16/93 06/01177 

9 10-5005 WF 03/21/91 99 0 1.54 1.54 03/21/91 06/01171 

10 13-5023 WN 10/27/94 80 0 1.91 02109/91 66 0 2.31 1.91 10/27/94 06/01174 

11 16-5025 DF 08/01/95 182 0 0.84 09/20/89 121 0 1.26 0.84 08/01/95 09/01172 

12 17-5020 WF 07/15/91 19 0 8.03 05/13/91 134 0 1.14 1.14 05/13/91 10/01/86 

13 17-5151 78/1990 WF 10/01/66 

14 17-5843 WF 08/02188 76 0 2.01 10/15/90 64 1 2.38 2.01 08/02188 09/01/82 

15 17-5849 WF 08/04/88 215 0 0.71 06/24/89 231 O. 0.66 0.66 06/24/89 11/01171 

16 17-5854 WF 08/04/88 125 0 1.22 06/24/89 127 0 1.20 1.20 06/24/89 01/01/82 

17 17-5869 WF 08/04/88 107 0 1.43 06/24/89 96 0 1.59 1.43 08/04/88 12101179 

18 17-5908 WF 03/24/93 86 0 1.77 05/10/91 82 0 1.86 1.77 03/24/93 04/01171 

19 17-9267 WF 07/07/89 212 0 0.72 05/07/90 184 0 0.83 0.72 07/07/89 10/01/66 

20 18-5022 78/1993 WF 07/13/88 77 0 1.98 09/25/89 75 2 2.03 1.98 07/13/88 01/01172 

21 18-5043 WF 05/09/91 119 0 1.28 1.28 05/09/91 01/01/69 

22 18-5518 78/1993 WF 12101/89 165 0 0.92 0.92 12/01/89 12101170 

23 19-5042 WF 09/07/89 140 0 1.09 05/18/91 132 0 1.16 1.09 09/07/89 12101175 

24 19-5046 WF 08/30/94 81 0 1.88 05/18/91 15 1 10.17 1.88 08/30/94 11/01175 

25 19-9116 78/1989 WF 07/28/89 210 0 0.73 0.73 07/28/89 08/01172 

26 24-5807 WF 10/11/89 13 0 11.73 10/11/89 06/01/90 

27 26-5363 WF OS/21/93 162 0 0.94 07/18/90 67 0 2.28 0.94 OS/21/93 12101176 

28 27-5076 78/1990 WF 06/09/89 227 0 0.67 0.67 06/09/89 10/01170 

29 28-3099 78/1992 WN 03/07/91 238 0 0.64 02114/91 0 0.64 03/07/91 11/01170 

30 28-5006 WN 03/04/91 172 0 0.89 03/03/91 132 0 1.16 0.89 03/04/91 04/01179 

31 28-5025 WN 07/13/93 129 0 1.18 01/14/91 116 0 1.31 1.18 07/13/93 07/01177 

3228-5803 WF 11/29/95 124 0 1.23 01/10/90 80 0 1.91 1.23 11/29/95 09/01179 

33 28-5805 WN 03/07/91 154 0 0.99 01/15/91 143 0 1.07 0.99 03107/91 06/01175 

34 29-5047 WF 08/19/88 99 0 1.54 06/20/90 88 0 1.73 1.54 08/19/88 07/01172 

35 31-5052 WF 04/19/93 118 0 1.29 05/15/89 127 0 1.20 1.20 05/15/89 12101/69 

36 37-5037 WN 01/29/96 120 0 1.27 03/10/91 96 0 1.59 1.27 01/29/96 10/01172 

37 37-5826 78/1995 WF 03/11/91 107 0 1.43 1.43 03/11/91 06/01177 

38 37-5827 WF 12117/96 82 0 1.86 03/19/91 66 0 2.31 1.86 12117/96 03/01173 

39 38-5002 WF 12106/90 228 0 0.67 0.67 12106/90 11/01173 

4039-5003 WF 07/13/94 161 0 0.95 10/03/90 0 0.95 07/13/94 09/01/88 

41 39-5010 78/1990 WF 11/29/88 141 0 1.08 1.08 11/29/88 07/01175 

4240-4158 WN 11/04/92 90 0 1.69 03/14/91 67 0 2.28 1.69 11/04/92 06/01/89 

4340-4166 WN 11/01/94 144 0 1.06 10/30/90 26 0 5.87 1.06 11/01/94 06/01/90 
'"

Table 5. GPS-5 data summary (continued).

Least

Average

Crack

Spacing

from Date

Manual Manual PADIAS PADlAS Manual Tested for

Manual Total High Average PADIAS Total High Average and Least 

Manual Total Severity Crack PADIAS Total Severity Crack PADIAS Average Open-to- 

Section Current Climatic Survey Trans. Trans. Spacing, Survey Trans. Trans. Spacing, surveys, Crack Traffic 

No. Section ID Status Region Date Crack No. Crack No. m Date Crack No. Crack No. m m Spacing Date 

44 40-5021 WF 11/01/94 132 0 1.16 10/30/90 83 0 1.84 1.16 11/01/94 10/01/87 

45 41-5005 DF 09/18/89 33 0 4.62 09/18/89 10/01/85 

46 41-5006 DF 04/30/96 137 16 1.11 09/18/89 112 67 1.36 1.11 04/30/96 06/01173 

47 41-5008 DF 04/29/96 166 0 0.92 09/18/89 178 0 0.86 0.86 09/18/89 06/01172 

48 41-5021 WN 06/27/94 226 1 0.67 07/26/89 148 0 1.03 0.67 06/27/94 07/01/86 

49 41-5022 WN 05/23/96 137 0 1.11 09/08/89 93 0 1.64 1.11 05/23/96 10/01/84 

50 41-7081 DF 09/18/89 3 0 09/01/88 

51 42-1598 WF 07/27/95 82 0 1.86 03/25/90 79 0 1.93 1.86 07/27/95 01/01175 

52 42-1617 7B/1991 WF 06/01172 

53 42-5020 WF 09/12190 104 0 1.47 1.47 09/12190 05/01/80 

54 45-5017 WN 06/07/93 101 0 1.51 03/05/91 88 0 1.73 1.51 06/07/93 03/01179 

55 45-5034 WN 03/17192 101 0 1.51 03/05/91 100 0 1.53 1.51 03/17192 06/01175 

56 45-5035 WN 06/08/93 224 0 0.68 06/05/90 160 0 0.95 0.68 06/08/93 11/01175 

57 46-5020 DF 10/05/93 249 0 0.61 12111190 226 0 0.67 0.61 10/05/93 08/01173 

58 46-5025 DF 05/02189 246 0 0.62 12117/90 236 0 0.65 0.62 05/02189 11/01174 

59 46-5040 WF 12115/90 330 0 0.46 0.46 12115/90 07/01/63 

60 48-3719 WN 06/08/95 125 1 1.22 02127191 95 1 1.61 1.22 06/08/95 01/01/65 

61 48-3779 DN 11/07/95 131 0 1.16 09/11/90 112 0 1.36 1.16 11/07/95 06/01178 

62 48-5024 WN 07/10/95 129 2 1.18 10/12190 83 8 1.84 1.18 07/10/95 01/01/82 

63 48-5026 WN 06/06/95 144 0 1.06 02126191 94 0 1.62 1.06 06/06/95 06/01/88 

64 48-5035 WN 06/30/95 139 0 1.10 10/27/90 86 0 1.77 1.10 06/30/95 09/01179 

65 48-5154 WN 07/10/95 108 0 1.41 10/12190 94 0 1.62 1.41 07/10/95 08/01171 

66 48-5274 WN 02111/97 75 0 2.03 10/29/90 60 0 2.54 2.03 02111197 03/01173 

67 48-5278 DN 06/05/95 176 0 0.87 01/24/91 156 0 0.98 0.87 06/05/95 06/01175 

68 48-5283 WN 02113/97 117 0 1.30 10/27/90 45 0 3.39 1.30 02113/97 04/01/88 

69 48-5284 WN 02113/97 83 0 1.84 10/27/90 21 0 7.26 1.84 02113/97 03/01/88 

7048-5287 WN 02114/97 143 0 1.07 10/27/90 101 0 1.51 1.07 02114/97 08/01173 

71 48-5301 WN 02113/97 123 6 1.24 10/27/90 89 0 1.71 1.24 02/13/97 02101182 

7248-5310 WN 02111/97 86 0 1.77 03/11/91 55 0 2.77 1.77 02111197 07/01/87 

7348-5317 WN 02111/97 74 0 2.06 03/21/89 58 0 2.63 2.06 02111197 04/01/82 

7448-5323 WF 08/10/95 235 1 0.65 04/24/89 190 0 0.80 0.65 08/10/95 10/01/80 

7548-5328 WN 08/05/93 133 0 1.15 03/11/91 104 0 1.47 1.15 08/05/93 09/01175 

7648-5334 WF 08/11/95 219 0 0.70 04/25/89 215 0 0.71 0.70 08/11/95 04/01170 

77 48-5335 WF 08/10/95 209 0 0.73 04/24/89 184 0 0.83 0.73 08/10/95 10/01/80 

7848-5336 WF 08/08/95 162 0 0.94 01/11/90 87 0 1.75 0.94 08/08/95 12101186 

7951-2564 WN 03/20/91 166 0 0.92 0.92 03/20/91 02101169 

80 51-5008 WN 03/20/91 156 0 0.98 0.98 03/20/91 08/01177 

81 51-5009 WN 12118/96 128 2 1.19 03/20/91 79 0 1.93 1.19 12118196 06/01/80 

8251-5010 WN 03/20/91 25 0 6.10 03/20/91 10/01/88 

83 54-5007 WF 05/01/91 212 2 0.72 0.72 05/01/91 06/01177 

84 55-5037 WF 08/24/88 85 0 1.79 10/19/90 109 0 1.40 1.40 10/19/90 11/01173 

85 55-5040 WF 11/07/94 118 0 1.29 09/12189 90 0 1.69 1.29 11/07/94 11/01/80 
.....

o

Table 5. GPS-5 data summary (continued).

Average

Depth Reinfor- Mean Split

Design % Reinfor- Long. Bar Trans. Bar cement Slab Average Tensile E Lab ESlab Base 

Section AvglRI, Long. cement, Spacing, Spacing, Place Thick, Compressive Strength, Tested, Backcalc., Thickness, 

No. Section 10 IRI Date mlkm Steel mm mm mm Method mm Strength, MPa MPa GPa GPa mm 

1 01-3998 05/04/90 1.32 0.59 76 168 762 Chairs 203 57.7 6.2 46.3 58.0 152 

2 01-5008 12110/90 0.94 0.68 114 185 965 Chairs 229 55.8 152 

304-7079 03/23/90 1.03 0.57 114 152 864 Chairs 229 4.7 27.2 102 

405-5803 09/23/94 1.45 0.61 102 102 406 Chairs 203 152 

505-5805 09/23/94 1.32 0.61 89 160 762 Chairs 203 53.7 178 

606-7455 05/01/91 1.23 0.56 102 165 1524 Chairs 213 4.8 32.0 54.0 137 

7 09-5001 04/12196 1.80 0.60 102 160 864 Chairs 203 62.9 4.6 36.7 44.9 254 

·8 10-5004 10/17193 1.18 0.60 97 152 Chairs 229 42.2 4.2 21.9 30.4 102 

9 10-5005 06/19/91 1.07 0.60 97 152 Chairs 203 34.5 4.8 18.6 36.6 102 

10 13-5023 05/17/94 1.26 0.60 99 152 Mech 216 49.9 5.3 33.2 43.2 152 

11 16-5025 09112194 2.39 0.61 64 229 Other 203 3.5 29.6 32.0 102 

12 17-5020 03/06/91 1.22 0.73 76 193 1219 Chairs 203 48.1 4.7 23.6 37.4 102 

13 17-5151 03/11/95 1.15 0.69 76 165 1219 Chairs 203 4.1 33.6 102 

14 17-5843 06/12190 1.18 0.71 58 185 1219 Mech 254 65.1 4.5 40.7 28.9 102 

15 17-5849 03/12190 1.58 0.70 Other 178 55.8 4.6 27.6 48.7 102 

16 17-5854 04/09/90 2.13 0.61 94 127 Mech 254 55.9 4.6 34.3 53.6 102 

17 17-5869 04/10/90 1.70 0.72 89 147 Mech 229 64.6 5.4 40.3 29.1 102 

18 17-5908 10/06/92 2.02 0.57 76 165 1219 Chairs 203 52.5 3.5 23.1 42.5 102 

19 17-9267 04/08/90 1.10 76 165 1219 Chairs 203 60.7 4.7 42.9 43.3 102 

20 18-5022 03/18/95 0.94 0.60 Mech 229 50.9 3.7 40.5 45.3 102 

21 18-5043 06113/91 2.41 0.60 Chairs 185 54.8 35.8 37.6 203 

22 18-5518 07/25/90 1.32 0.61 Chairs 229 44.9 4.9 33.2 38.1 152 

23 19-5042 06/19/90 1.70 0.65 89 216 Mech 203 56.2 4.3 30.0 50.3 102 

24 19-5046 09/16/94 1.55 0.65 89 216 Mech 203 51.7 31.2 45.5 102 

25 19-9116 04/08/90 0.84 0.65 76 216 Mech 203 48.2 3.4 33.8 45.7 102 

26 24-5807 12104/95 1.48 0.53 109 241 1372 Chairs 229 40.7 4.5 30.6 51.0 152 

27 26-5363 04/22193 1.83 0.70 102 165 Other 229 52.2 30.1 37.1 102 

28 27-5076 OS/22190 0.77 Other 229 62.2 5.2 37.2 42.5 152 

29 28-3099 10/09/91 1.47 0.61 102 165 1067 Chairs 203 68.6 5.6 39.1 32.8 152 

30 28-5006 12105/90 1.45 0.59 97 165 914 Chairs 203 64.8 5.2 34.6 32.0 152 

31 28-5025 08/01/95 1.41 0.59 97 165 914 Chairs 203 47.8 102 

32 28-5803 01/27/94 1.55 0.59 97 165 914 Mech 203 53.7 4.9 31.5 28.5 152 

33 28-5805 06/04/90 1.30 0.59 76 165 762 Chairs 203 70.2 102 

34 29-5047 03/19/90 1.59 0.60 89 152 1219 BTW 203 47.0 5.0 34.8 55.5 102 

35 31-5052 11/20/89 1.05 0.75 64 152 914 Chairs 203 40.1 4.2 25.7 62.2 76 

36 37-5037 11/16/94 1.07 0.60 102 762 305 Chairs 203 55.6 4.9 21.4 34.6 102 

37 37-5826 03/26/91 1.22 0.65 76 152 762 Other 203 55.5 4.7 28.4 40.7 38 

38 37-5827 04/25/96 0.99 0.60 76 152 762 Other 203 44.9 3.7 22.2 38.8 102 

39 38·5002 10/25/89 1.26 0.60 102 165 1219 Mech 203 41.5 51 

40 39·5003 04/04/94 1.15 0.96 102 160 762 Chairs 254 51.7 5.4 26.2 41.2 102 

41 39-5010 09/28/89 1.84 Other 203 102 

42 40-4158 08/28/91 1.03 0.61 127 185 1118 Mech 262 40.0 114 

43 40-4166 11/17/93 0.95 0.72 127 185 1118 Mech 259 56.3 4.5 33.4 45.3 102 
......

......

Table 5. GPS-5 data summary (continued).

Average

Depth Reintor- Mean Split

Design % Reintor- Long. Bar Trans. Bar cement Slab Average Tensile E Lab ESlab Base 

Section Avg IRI, Long. cement, Spacing, Spacing, Place Thick, Compressive Strength, Tested, Backcalc., Thickness, 

No. Section 10 IRI Date mlkm Steel mm mm mm Method mm Strength, MPa MPa GPa GPa mm 

44 40-5021 09/16/93 0.94 0.59 114 147 1118 Mech 229 48.7 89 

45 41-5005 11/17/89 1.32 0.51 122 147 1524 Chairs 279 5.8 31.5 60.4 165 

46 41-5006 OS/20/97 1.43 0.51 102 165 1524 Chairs 203 3.6 28.4 73.7 152 

47 41-5008 10/20/89 0.93 0.51 102 165 1524 Chairs 203 3.3 31.3 37.8 102 

48 41-5021 03/31/93 1.09 0.51 109 165 1524 Mech 274 5.3 22.9 41.5 229 

49 41-5022 11/18/89 0.94 0.51 76 122 1524 Chairs 305 5.5 24.3 33.3 508 

50 41-7081 OS/20/97 0.82 0.70 109 165 914 Chairs 254 5.1 26.0 51.0 203 

51 42-1598 11/08/95 1.81 0.65 89 147 864 Chairs 229 65.0 4.4 43.1 36.9 203 

52 42-1617 11/10/95 0.84 0.64 89 152 864 Chairs 229 41.3 5.5 40.0 38.2 203 

53 42-5020 05/16/90 1.81 0.65 89 203 864 Chairs 229 48.6 4.2 43.8 59.3 152 

54 45-5017 04/29/92 2.05 0.57 99 152 762 Chairs 229 44.8 5.9 20.8 35.2 152 

55 45-5034 04/29/92 1.42 0.64 89 152 762 Chairs 203 47.4 3.8 21.5 36.0 127 

56 45-5035 04/10/94 1.22 0.64 89 152 762 Chairs 203 50.7 3.6 24.3 40.8 127 

57 46-5020 06/16/93 0.97 0.59 64 165 1219 Chairs 203 54.0 4.5 27.6 34.5 51 

58 46-5025 11/18/89 1.31 0.59 64 165 1219 Chairs 203 56.8 5.0 29.8 45.6 76 

59 46-5040 11/13/89 1.99 0.65 64 152 1118 Chairs 203 73.4 5.6 33.2 39.4 76 

60 48-3719 02103/95 2.29 0.51 102 191 610 Chairs 203 51.9 4.3 44.1 46.5 102 

61 48-3779 10/13/94 2.23 0.51 102 191 914 Chairs 203 35.5 51 

62 48-5024 01/31/95 2.32 0.60 127 185 914 Chairs 254 65.1 102 

63 48-5026 02101/95 1.72 0.56 127 198 610 Mech 254 62.7 5.7 37.7 48.7 152 

64 48-5035 12107/94 1.86 0.61 102 160 914 Chairs 203 36.0 152 

6548-5154 01/30/95 1.66 0.52 102 191 914 Chairs 203 66.9 102 

66 48-5274 12108/94 1.66 0.51 102 191 914 Chairs 203 36.6 102 

67 48-5278 11/16/94 1.67 0.61 76 216 914 Chairs 152 59.9 102 

6848-5283 12107/94 1.18 0.52 127 216 610 Chairs 254 38.6 51 

6948-5284 12107/94 2.43 0.50 140 203 610 Chairs 279 39.0 51 

7048-5287 12106/94 2.02 0.51 102 191 914 Chairs 203 29.0 102 

71 48-5301 12105/94 1.69 0.60 127 185 914 Chairs 254 46.6 51 

72 48-5310 12/06/94 2.01 0.50 140 203 610 Chairs 279 34.6 102 

7348-5317 12112194 2.34 0.51 102 191 914 Chairs 203 51.7 51 

7448-5323 11/22194 1.79 0.61 114 203 914 Mech 229 57.0 4.1 29.3 38.1 152 

7548-5328 04/21/93 1.59 0.61 102 160 914 Chairs 206 45.1 109 

7648-5334 01/12195 1.10 0.51 97 191 762 Other 203 47.4 4.8 35.0 37.5 102 

77 48-5335 11/22194 2.01 0.61 114 203 914 Mech 229 63.9 4.9 35.0 28.9 152 

7848-5336 11/21/94 1.42 0.61 114 203 914 Mech 229 43.9 152 

79 51-2564 06/21/91 0.97 0.60 89 152 Mech 203 51.6 4.4 24.8 29.6 152 

8051-5008 06/21/91 2.07 0.60 89 152 Mech 203 45.2 5.0 25.1 36.3 127 

81 51-5009 12113/95 2.17 0.60 89 152 Mech 203 50.2 4.3 25.3 53.7 152 

82 51-5010 12107/89 1.55 0.65 102 191 Mech 229 39.0 4.6 31.0 53.3 203 

8354-5007 11/15/91 2.35 0.65 76 Chairs 203 57.7 5.2 21.9 24.0 152 

84 55-5037 09/17/95 1.14 0.61 76 229 Mech 203 59.4 5.8 34.6 49.4 152 

85 55-5040 07/14/94 2.39 0.65 76 216 Other 203 54.9 5.4 42.7 43.3 152 
......

N

Table 5. GPS-5 data summary (continued).

Average

Annual Average

Freeze Daily

k-value AASHTO Outside Index, Annual Temp.

Section Backcalc., Soil Soil Type Shoulder degrees C precip., Range, KESAL_

No. Section ID Bond MPalmm Classif. Coarse/Fine Type days mm degrees C 18k Total

1 01-3998 1.0 91 A-2-4 C PCC (JPCP) 30 1423 13.6 6912

201-5008 1.0 44 A-5 F PCC (JPCP) 41 1345 13.8 8840

304-7079 A-6 F PCC (JPCP) 0 706

405-5803 A-4 F AC 69 1336 11.9 1820

505-5805 1.0 159 PCC(JPCP) 73 1298 11.9 2723

606-7455 1.0 42 A-6 F AC 1 270 15.1 8971

709-5001 1.0 33 A-2-4 C AC 397 1243 12.2 15646

8 10-5004 0.0 36 A-1-b C AC 197 1094 10.5 40312

9 10-5005 1.0 78 A-4 F PCC (JRCP) 125 1160 11.6 5976

10 13-5023 1.0 69 A-3 C AC 2 1266 11.2 21332

11 16-5025 1.0 103 A-1-a C AC 543 370 17.0 14502

12 17-5020 0.0 48 A-6 F PCC (JPCP) 196 1036 12.1 321

13 17-5151 A-4 C PCC (JRCP) 17451

14 17-5843 1.0 57 A-6 F AC 548 820 11.4 4897

15 17-5849 1.0 65 A-4 F AC 468 1000 11.8 10250

16 17-5854 0.0 51 A-6 F AC 462 968 11.9 708

17 17-5869 1.0 78 A-4 F AC 506 979 11.6 1136

18 17-5908 1.0 58 A-1-b C AC 255 58 12.4 2465

19 17-9267 1.0 82 A-1-b C PCC(JRCP) 565 925 10.7 16311

20 18-5022 1.0 73 A-4 F AC 393 1055 11.6 63112

21 18-5043 1.0 70 A-7-6 F AC 202 1160 11.3 326

22 18-5518 1.0 73 A-2-4 C AC 442 935 11.1 68028

23 19-5042 1.0 57 A-4 F AC 823 828 12.0 5923

24 19-5046 1.0 83 A-2-4 C AC 814 820 11.9 8451

25 19-9116 1.0 58 A-6 F AC 933 821 11.4 6894

26 24-5807 1.0 69 A-4 F PCC(JPCP) 131 1075 11.0

27 26-5363 1.0 59 A-2-4 C AC 483 860 10.6 3989

28 27-5076 1.0 46 A-4 F AC 943 798 11.1 5488

29 28-3099 1.0 44 A-7-6 F PCC(JRCP) 18 1570 14.0 2490

30 28-5006 1.0 120 A-7-6 F AC 57 1387 12.8 2369

31 28-5025 0.0 103 A-2-4 C PCC (JRCP) 24 1561 13.5 1502

32 28-5803 1.0 61 A-2-4 C AC 97 1441 12.7 5115

33 28-5805 1.0 57 A-3 C AC 4 1655 10.5 11144

34 29-5047 1.0 42 A-6 F PCC(JRCP) 305 958 12.3 5397

35 31-5052 1.0 43 A-7-6 F AC 574 734 11.5 5263

3637-5037 1.0 55 A-5 C AC 83 1175 13.4 12365

3737-5826 1.0 34 A-4 F AC 95 1150 13.7 8239

38 37-5827 1.0 31 A-l-b C AC 89 1163 12.3 3117

39 38-5002 1.0 32 A-7-6 F PCC(JPCP) 1299 510 12.0 4977

40 39-5003 1.0 125 A-4 F PCC(JPCP) 364 952 10.8 822

41 39-5010 A-4 F AC 429 980 12.6 2272

4240-4158 1.0 84 A-2-4 C PCC (JPCP) 80 1072 13.6 9229

4340-4166 1.0 106 A-6 F PCC(JPCP) 55 1686 12.3 10481
V.l

-

Table 5. GPS-5 data summary (continued).

Average

Annual Average

Freeze Daily

k-value AASHTO Outside Index, Annual Temp.

Section Backcalc., Soil Soil Type Shoulder degrees C precip., Range, KESAl_

No. Section ID Bond MPalmm Classif. Coarse/Fine Type days mm degrees C 18k Total

44 40-5021 1.0 75 A-6 F PCC (JPCP) 141 1065 12.9 6739

45 41-5005 0.0 67 A-6 C AC 12 377 11.7 11026

46 41-5006 1.0 38 A-7-6 F AC 210 426 13.5 13754

47 41-5008 1.0 145 A-2-6 C AC 212 428 13.4 9958

48 41-5021 1.0 71 A-4 F AC 27 1117 12.7 11588

49 41-5022 1.0 50 A-6 F AC 26 1128 12.3 16927

50 41-7081 0.0 97 A-1-b C AC 124 176 11.8 1466

51 42-1598 1.0 107 A-2-4 C PCC(JRCP) 240 1033 10.5 22826

52 42-1617 1.0 99 C AC 202 1132 11.3 6381

53 42-5020 1.0 51 A-4 F AC 216 1116 11.5 5118

54 45-5017 1.0 164 A-2-4 C AC 20 1175 12.9 8299

55 45-5034 1.0 120 A-2-4 C AC 16 1147 13.3 4972

56 45-5035 0.0 74 A-2-4 C AC 15 1138 13.0 6039

57 46-5020 1.0 125 A-2-4 C AC 620 451 15.8 947

58 46-5025 1.0 39 A-7-6 F AC 576 400 15.0 555

59 46-5040 1.0 39 A-6 F AC 910 606 12.5 1343

60 48-3719 1.0 47 A-7-6 F PCC (JRCP) 3 1518 10.5 9199

61 48-3779 1.0 48 AC 11 264 16.1 9325

62 48-5024 1.0 85 A-2-6 C PCC (JPCP) 15 999 14.1 1522

63 48-5026 1.0 53 A-7-6 F PCC (JPCP) 9 1123 9.8 239

64 48-5035 1.0 209 PCC (JPCP) 35 934 12.0 9492

65 48-5154 1.0 130 A-2-7 C AC 8 953 12.2 10317

66 48-5274 1.0 75 A-2-7 C AC 38 861 12.4 5929

67 48-5278 1.0 168 A-2-4 C AC 33 404 15.2 1189

68 48-5283 1.0 102 A-2-6 C PCC (JPCP) 48 965 12.5 1551

69 48-5284 1.0 84 A-2-6 C PCC (JPCP) 48 969 12.6 1019

70 48-5287 0.0 66 A-5 F AC 37 864 12.6 4538

71 48-5301 1.0 129 A-6 F PCC (JPCP) 52 838 12.9 1765

72 48-5310 1.0 95 A-7-6 F PCC (JRCP) 44 946 13.6 2238

7348-5317 0.0 47 A-2-7 C PCC (JRCP) 38 888 12.5 4426

7448-5323 1.0 61 A-6 F PCC (JPCP) 139 566 15.3 9748

75 48-5328 1.0 62 A-5 F PCC (JRCP) 55 859 12.7 7292

7648-5334 1.0 102 A-4 F PCC(JRCP) 133 574 15.0 11754

77 48-5335 1.0 61 A-6 F PCC (JPCP) 130 584 15.3 8914

7848-5336 1.0 79 A-7-5 F PCC (JPCP) 135 526 15.9 1486

79 51-2564 0.0 90 A-4 F AC 45 1178 10.2 11755

80 51-5008 0.0 85 A-4 F AC 48 1159 9.7 10505

81 51-5009 0.0 87 A-2-4 C AC 76 1077 12.2 2207

82 51-5010 0.0 101 A-7-6 F PCC (JPCP) 71 1092 12.2 381

8354-5007 0.0 50 A-4 F AC 313 1219 13.0 1751

84 55-5037 1.0 78 A-1-b C AC 1086 811 12.9 2627

85 55-5040 1.0 49 A-7-S F PCC (JPCP) 523 845 9.3 9118
32

28

24

20

ro

Q)

>.

Q)- 16 C>

oct:

12

8

4

0

Section Reference Number

Figure 1. Age as oflatest distress survey.

I--

35

30

25

20

ro

Q)

>.

15

oct:

10

5

0

..... LO Ol N w ffi 00

Section Reference Number

Figure 2. Age as ofDecember 31, 1997.

14
Figure 4. Design percent longitudinal steel.

15
150.00

135.00

120.00

E 105.00 E

...

c:

Ql 90.00 E

Ql

.e 75.00 c:

.iii

c:: 60.00 0

.-

..c:

.-

0- 45.00

30.00

15.00

0.00

m N M ID $

Section Reference Number

Figure 5. Depth to longitudinal reinforcement.

250.00,- -,

E

200.00

E

Ol

c:

'0

ro 150.00

0-

W

...

ro

aJ

(i'j 100.00 c:

:a

::J

.-'5>

c:

0

-oJ 50.00

0.00

Section Reference Number

Figure 6. Longitudinal bar spacing.

16
w $ 00

Section Reference Number

400.00

600.00

800.00 -I-Hf--III------

1400.00 +----1:..-------------

1200.00 -/----1--

1600.00 r-------------------------------.

200.00

0.00

E

E

1000.00 -/----1--

'0

co

coo

Figure 7. Transverse bar spacing.

2. Most sections have 0.62 percent or less longitudinal steel. Only 10 sections had

steel equal to or greater than 0.7 percent. Fifteen sections had steel equal to or less

than 0.5 percent.

3. Depth oflongitudinal reinforcement was generally greater than 75 rom.

4. Spacing oflongitudinal bars was generally more than 150 rom.

5. Where transverse bars were used, bar spacing was generally greater than 600 rom.

Base and Subgrade Inventory Data

Base material was characterized by material type as presented in table 5. The material type

codes used in table 5 are as follows:

G

SC

ACM

CAM

LC

LT

CT

PAM

Gravel

Soil Cement

Dense-Graded, Hot-Laid, Central-Plant AC Mix

Cement-Aggregate Mixture

Lean Concrete

Lime-Treated Subgrade Soil

Cement-Treated Subgrade Soil

Pozzolanic-Aggregate Mixture

17
Data for the subgrade includes American Association of State Highway and Transportation

Officials (AASHTO) soil classification and classification by soil particle size as coarse-grained

(C) and fine-grained (F) (given in table 5). The subgrade type for 43 percent ofthe GPS-5

sections was identified as coarse-grained and 57 percent were identified as fine-grained based on

the inventory data. The actual percentage distribution for subgrade types according to AASHTO

classification (based on field sampling and laboratory testing) is given in table 6.

Table 6. Percentage distribution ofAASHTO subgrade types for GPS-5 sections.

AASHTO Classification No. of Sections Percent Distribution

A-l-a 1 1.2

A-l-b 6 7.1

A-2-4 15 17.6

A-2-6 4 4.7

A-2-7 3 3.5

A-3 2 2.4

A-4 18 21.2

A-5 4 4.7

A-6 15 17.6

A-7-5 1 1.2

A-7-6 12 14.1

Not Known 4 4.7

Shoulder Type

Information on outside shoulder type is given in table 5. Forty percent ofthe GPS-5

sections have concrete shoulders and 60 percent ofthe sections have AC shoulders. The concrete

shoulders are typically plain jointed concrete. However, there are a few jointed reinforced

concrete shoulders. There are no CRC shoulders.

Climatic Data

Climatic data for GPS-5 sections include climatic region type, average annual freezing

index, average annual precipitation, and average daily temperature range. The key climatic data

for GPS-5 sections are given in table 5 and are presented in figures 8 through 10. The climatic

data are based on values averaged over the years that each section has been in service.

Traffic Data

The cumulative 80-kN equivalent single-axle load (ESAL) was used to characterize traffic

loading. The cumulative 80-kN ESALs to the date ofthe distress survey were evaluated by

summing the estimated annual 80-kN ESALs over the years the sections were in service up to the

time ofthe latest distress survey. In the cases where some ESAL values were missing for a few

years, regression analysis was used to estimate the annual total ESALs for these years.

18
Figure 9. Annual precipitation summary.

19
18.00

16.00

()

0

a) 14.00

0

c::

12.00

i:5

::l 10.00 +oJ

£!!

Q)

a.

E 8.00

'(6 6.00

0

Q)

C)

£!! 4.00

2.00

0.00

.... LO 0> N M w w

Section Reference Number

Figure 10. Average daily temperature range.

Section 24-5807 had no traffic data and was therefore not considered in subsequent analyses. A

summary ofthe ESAL data is given in figure 11.

Profile Data

International Roughness Index (IRI) is one ofthe indices used in the LTPP program for

characterization of pavement section roughness. IRI values determined at different test times over

the years are available in the database. Values at times that correspond to the latest distress survey

dates were used for characterization of profile condition ofpavement sections. A summary ofIRI

data is given in table 5 and figure 12. The IRI values for GPS-5 sections ranged from about 0.7 to

2.4 m/km, with a large number ofsections exhibiting IRI values less than 1.8 m/km. Considering

the service lives ofthe CRC sections in the GPS-5 experiment, the CRC pavements are exhibiting

good ride characteristics.

Crack Spacing Data

The CRC pavement distress data under the LTPP program are available from two types of

condition surveys: the manual distress survey and the photographic survey using the PADIAS

system. For the purposes ofthe analysis presented in this report, the following guidelines were

used:

20
70000.00.-- --,

60000.00 +------+-1---------------------1

8' 50000.00 +------+-1-----------------------1

o

....

L

40000.00 +---.----+-1-----------------------1

C/)

w

!!o! 30000.00 +----+---+-1---------------------1

:;

§ 20000.00 +---+-1---+-1-------------+------------\ U

10000.00 -l----II---II--I--tc--H----I---------I------I----=JI0.00

..... LO en

Section Reference Number

Figure 11. Cumulative ESAL summary.

2.50

2.00

E

1.50 -E

Q;

Q)

C)

1.00

0.50

l- i0.00

LO en N w m

Section Reference Number

Figure 12. Average IRI summary.

21
1. If data from several survey dates were available, the information from the latest

survey was used.

2. Ifthe manual and PADIAS surveys indicated a different number of cracks or local

failures for the same section, the survey that recorded the maximum number of

cracks was used.

Average transverse crack spacing was calculated by dividing the length ofthe section by

the total number of cracks. The total number oflocalized failures was found as a summation of

the total number ofrigid and flexible patches and punchouts. Table 5 gives a summary of GPS-5

distress survey data. Generally, PADlAS surveys predicted larger crack spacings compared to the

manual survey, as shown in figure 13. The crack spacing shown in figure 13 is based on the most

recent surveys listed in table 5. Overall, the average crack spacing for the GPS-5 test sections was

found to be about 1.2 m (4 ft) based on manual surveys. It appears that the photographic

procedure fails to adequately identify all low-severity transverse cracking.

Out of 85 sections, there were 2 sections without both manual survey data and PADIAS

survey data (sections 17-5151 and 42-1617). These two sections were excluded from transverse

cracking analysis. There were four other sections with unreasonably large crack spacing

calculated from the PADIAS distress survey (sections 24-5807, 41-5005, 41-7081, and 51-5010).

These four sections did not have manual surveys. These four sections were also excluded from

the transverse cracking analysis.

Both manual and automatic surveys indicate a very small percentage ofhigh-severity

transverse cracking and a moderate amount ofmedium-severity cracking in all the sections, as

summarized in table 7.

Table 7. Severity oftransverse cracking.

Percentage ofCracking

Survey Type Low-Severity Cracks Medium-Severity Cracks High-Severity Cracks

Manual 78.91 21.74 0.26

PADIAS 63.14 36.27 0.59

Note: Based on total amount of cracking.

Punchout and Patching Data

The total number of punchouts and patches for each section is given in table 5. It is seen

that localized failures have not been a serious problem to date at the GPS-5 sections. There were

16 sections exhibiting localized failure, as summarized below:

22
12.00

10.00

E

d)

c:::: 8.00 .~

0-

W

.:Jt:. 6.00 u

l!!

(J

Q)

4.00

2.00

0.00

I

11~~n~~111 In~ ,. II~~ Iln~~ '" I ~~~ f--

I~nnl I~ Inn

... II) en ('I")

... N re m

Section Reference Number

• PADIAS 0 M6.NUAL

Figure 13. Average crack spacing.

Total Number of Failures

1

2

3

4

5

6

Number of Sections

5

5

3

1

o

2

One section reportedly exhibited 23 punchouts/patches. This is considered an error in

interpretation ofthe distress data. Twenty-three localized failures over a length of 152.4 m would

equate to a rate of about 150 localized failures per kilometer. It is unlikely that any highway

agency would permit such a high amount oflocalized failures to remain on a public highway.

It should be noted that, as shown in table 5, none ofthe nine sections that have been

overlaid and the one section that was taken out ofthe study exhibited no localized failures. Also,

eight ofthe nine overlaid sections had IRI values less than 1.5 m/km. The section that was taken

out ofthe study had an IRI value of2.35 m/km at the time ofthe last profile survey. It thus

appears that the appropriate overall pavement projects are performing far worse than the overlaid

test sections. It further appears that performance evaluation ofCRC pavements should

incorporate longer lengths of pavement to ensure that representative failure conditions in the

pavement are reliably obtained. Thus, the visual condition survey should include a survey of 5- to

23
8-km lengths ofthe CRC pavement in addition to a detailed survey ofthe 152.4-m (500-ft)

monitoring length ofthe test section. The longer visual condition survey should record at least the

number and severity of punchouts, patches, and other localized failures.

Summary

The small amount oflocalized failures observed at the GPS-5 test sections limits the type

of analysis that can be carried out to evaluate the performance ofCRC pavements. It appears that

most ofthe CRC pavements are performing well, or rather, exceptionally well. This observation

is also supported by the low lRI values determined for the GPS-5 test sections.

24
CHAPTER3. EVALUATION OF CRACK SPACING DATA

Introduction

It is well established that transverse crack spacing in CRC pavements is influenced by the

percent oflongitudinal reinforcement, concrete strength, and slab/base interface friction. Recent

efforts have also shown that the transverse crack spacing pattern is influenced significantly by the

ambient weather conditions at the time of concrete placement and a few days thereafter. As such,

the long-term crack spacing pattern is influenced by the conditions during the first few days after

concrete placement. The LTPP database contains no data on ambient weather conditions during

time of concrete placement. In addition, data on specific dates of construction ofthe test section

portion ofthe roadways are not available. Thus, analysis ofthe crack spacing patterns for the

GPS-5 sections have to rely on other attributes that relate to the properties ofthe CRC pavement

and general climatic data.

Another data type that is currently not available is the data on individual crack spacing.

Without this data, analysis ofthe characteristics ofthe crack spacing pattern is not possible.

Previous studies have shown that frequency distribution curves for crack spacing and plots of

"average spacing ofthec1osest five cracks" (ASCFC) can be useful in understanding the behavior

ofCRC pavements and in determining potential areas offuture localized failures. The ASCFC

plots can identify poor crack spacing patterns within a section ofCRC pavements. Cluster

cracking areas and areas with large' crack spacings can be easily identified. Wide crack spacing

can result in premature crack spalling and "companion" punchouts at the location of wide cracks.

Typical frequency distribution curves and the plots of ASCFC are shown in figures 14 and 15. It

is believed that in the future, the interpretation of distress data will also include data on individual

crack spacing along the 152.4-m length of each GPS-5 test section. Future analysis oftheCRC

pavements will also benefit if actual distress survey maps are made available to the analysts.

Then it would be possible to relate the locations ofthe failures to crack spacing characteristics at

these locations.

Another data type that is missing from the LTPP database is the crack width data. No

attempt has been made to date to measure crack width at the GPS-5 test sections. Crack width

data are needed to study the correctness of applying various crack width criteria as part ofthe

design ofCRC pavements.

Bi-Variate Plots

The following independent variables were selected to analyze their effect on crack

spacing:

• Age at the time of distress survey.

• Cumulative ESALs.

• Slab thickness.

• Elastic modulus ofthe concrete.

• Design percent steel.

25

• Depth to the reinforcement.

• Freeze index.

• Annual precipitation.

• Daily temperature range.
o ..,_........,----.. -.- ._.-' -- ..........-., .,.,.."""" "...-.-- ..-- ...",.,..-",. ..--_..--- ...... ",,:" ;,," .. '- ""...- .... " .... " ';" .. ". "".... ,. .. I' "

,'

. I' ' "" .... / ' .. ..

I' " "" • "" / : / ,- "

/ .. ",,-

/ ,'~" .",- -" -IL-1 /. '

,'//

r--

/ " ""/ -'-'IL-2

/ .' "".. ..... ·IL-3

I :'/'.;"

., . --IL-4 l ,.,/ r--

I .'. - -- IL-5 I • / ' ." I' I • I.'

I .// J /

iF ~.

'I/ l / .. '"

1ft=O.:n; I' •

I~' / /.

flo""

100

ro

0

CD 00

>+:l

ca

"S

E

:::J 40

()

20

o

o 1 2 3 4 5 6 7 8 9 10 11 12 15 20

Figure 14. Typical crack spacing distribution plot for a CRC pavemenf.

Crack Spacing for IL-2

1200

Average

1 ft =0.305 m

600 800 1000

Acceptable

Range

200 400

12 ,--------------------------------,

11

10

9

8

7

6-+---++:-----:--r------"""*"~-->OO'd____r__t:_-_tV_'lrt_"_Tf_+_----__t

5

4HLHKH-H-tor+--\f-T-ft~fPr;:r_71r_+-+_t_-_+__f-..l.M_ll----_t_- ---t

3-+At-~-----l~lHt---'I-'_+_--''_t_1I_'t1I---~t__JfI_-.L.-----;?4_----__t

2

1

o+-----f--------+-----+-----+------+-----j

o

Location Within Site, ft

Figure 15. Typical plot ofASCFC for a CRC pavemenf.

26
The bi-variate plots oftransverse crack spacing with respect to the above-listed independent

variables are presented as follows:

Figure 16 - Crack spacing versus age.

Figure 17 - Crack spacing versus cumulative ESALs.

Figure 18 - Crack spacing versus slab thickness.

Figure 19 - Crack spacing versus concrete modulus of elasticity.

Figure 20 - Crack spacing versus percent longitudinal steel.

Figure 21 - Crack spacing versus percent longitudinal steel (age < 10 years).

Figure 22 - Crack spacing versus percent longitudinal steel (age> 10 years).

Figure 23 - Crack spacing versus depth to longitudinal reinforcement.

Figure 24 - Crack spacing versus annual air freezing index.

Figure 25 - Crack spacing versus annual precipitation.

Figure 26 - Crack spacing versus average daily temperature range.

Figure 27 - Crack spacing versus longitudinal bar spacing.

.... • • •

•* • • •

• • • ....

.--.

· •

• • •

• • • • • • •

* • • •• • • •

• ••• • • • • •

• • • • • • •

• • • • •

• • • *••: .

• • •

•

3.00

2.50

E

c'i 2.00

c:

'0

1i

C/)

1.50 0

e

u

Q)

C)

e 1.00

0.50

0.00

o 4 8 12 16

Age, years

20 24 28 32

Figure 16. Crack spacing versus age.

27
10000.00 20000.00 30000.00 40000.00 50000.00 60000.00 70000.00 80000.00

Cum ulative ESAL (*1000)

...

•• 'If

•• •

• •

..

•••••

•

• 1 ~. .

•

:....... •

.. -. • • •

.+: ••*..# •

•

2.50

3.00

0.50

0.00

0.00

E

ci 2.00 c:

'0

1lI

0-

en

13 1.50

e

(,)

CI)

Cl

e 1.00

Figure 17. Crack spacing versus cumulative ESALs.

*

• • • • * • •

•

• I

• • • ••

I • •

•

• •• a •

--.

3.00

2.50

E

ci 2.00 c:

'0

1lI

0-

en

13 1.50

l!!

(,)

CI)

Cl

e 1.00

0.50

0.00

100.00 150.00 200.00 250.00 300.00 350.00

Slab Thickness, mm

Figure 18. Crack spacing versus slab thickness.

28
• --.- • • • • •

• .......... •

• • • •

•• • •• •

.. • •

•• • • • •

•••

•

•

• • •

• • • • • • • • •

•• •

•

3.00

2.50

E

Ci 2.00 t::

'0

Cll

Co

en

1.50

l!!

U

CD

Cl

l!! 1.00

0.50

0.00

15.00 20.00 25.00 30.00 35.00 40.00 45.00 50.00

Figure 19. Crack spacing versus concrete modulus of elasticity, Es1ab'

•

: : i •

• ..... • ....

• • , •

• ,I• • • I • •

• • •

;1. • •

•

• • ••t •• •

•

3.00

2.50

E

Ci 2.00

c

'lj

Cll

Co

en

is 1.50

l!!

U

CD

Cl

l!! 1.00

0.50

0.00

0.45 0.50 0.55 0.60 0.65 0.70 0.75 0.80 0.85 0.90 0.95 1.00

% Steel

Figure 20. Crack spacing versus percent longitudinal steel.

29
3.00

2.50

E.2.00

Cl

c

'u

ClI

Q.

(J)

is 1.50

I.!

o

Q)

Cl i 1.00

C(

0.50

....

: •

•

• •

•

• • • • •

• •

•

0.00

0.45 0.55 0.65 0.75

% Steel

0.85 0.95

Figure 21. Crack spacing versus percent longitudinal steel (age < 10 years).

•

i • • .... • ....

• • •

I .'. • • •

•

·'1 • •

• • •• a •• •

•

3.0q

2.50

E

c)

c 2.00

'0

ClI

coo

0 1.50

I.!

u

Q)

C)

I.! 1.00

0.50

0.00

0.45 0.50 0.55 0.60 0.65

% Steel

0.70 0.75 0.80

Figure 22. Crack spacing versus percent longitudinal steel (age> 10 years).

30
80.00 90.00 100.00 110.00 120.00 130.00 140.00 150.00

Depth to reinforcement. nm

70.00

*

• • • • : • •

• ......

• • • •

• I • • I • • •• •

,

• •

• : •

• •

• • • • • •

• •

•

3.00

0.00

50.00 60.00

2.50

E 2.00 .~U

«l

Q.

Cf)

u 1.50

b

t

Ql 1.00 >

<

0.50

Figure 23. Crack spacing versus depth to longitudinal reinforcement.

*

: . ....

• •

• • .... • •

• • • • • ~~..

, • •

•• • •• • •

• •

.~. • • • • • •

•• \ • • •

• •

•• •

•

3.00

2.50

E 2.00 di

.S;

Cf)

1.50

Ql

til

f!!

Ql 1.00 >

<

0.50

0.00

0.00 200.00 400.00 600.00 800.00 1000.00 1200.00 1400.00

Freezing .,dex. °Cdays

Figure 24. Crack spacing versus annual air freezing index.

31
......

• .... •

•• • • • •

• ......

• .. .... I . ... • •

• • •••# • ••

• .~ •• t •

• • - .... •• ... ...

• ., •• • • .. • •

•• •

•

3.00

2.50

E

oj 2.00 c

'uIII

Q.

en

0 1.50 III

0

Q)

Cl

III

...

Q) 1.00 >

«

0.50

0.00

0.00 200.00 400.00 600.00 800.00 1000.00 1200.00 1400.00 1600.00 1800.00

Annual A"ecipitation, mn

Figure 25. Crack spacing versus annual precipitation.

.... i .... • • •••

• •

•

• • .........

• ...... •

• • •• •• • • +;.. :: ,. •

• t. ... •••• • •

....

• • • •

.t • ~: •

•

3.00

2.50

E

oj 2.00

.

0

III

Q.

en

1.50 0

III

0

Q)

Cl

III

...

Q) 1.00

>

«

0.50

0.00

5.00 7.00 9.00 11.00 13.00 15.00 17.00 19.00

Daily Terrperature Range, OC

Figure 26. Crack spacing versus average daily temperature range.

32
*

•• : •

• •

•

•• • • • • •

,*. •

•• •• *, ••• •

• ; ·1 • • •

• •• • • • •

•

3.00

2.50

E

ci 2.00 c:

'0

III

a.

(J)

.:JI:. 1.50 0

e!

u

Q)

C)

...

III 1.00

0.50

0.00

50.00 75.00 100.00 125.00 150.00 175.00 200.00 225.00 250.00

Longitudinal Bar Spacing, mm

Figure 27. Crack spacing versus longitudinal bar spacing.

It is seen from a review offigures 16 through 27 that no clear trends are evident on the

basis ofbi-variate analysis ofthe data. The long-term crack spacing pattern, as represented by

average crack spacing, is dependent on the interactions of possibly all ofthe independent variables

considered together with the ambient conditions during the first few days of construction. As

such, an understanding ofthe effect ofthe variables noted would have to consider the interactions

and the confounding effects of each ofthe variables. One method to account for these effects is to

use multiple regression analysis. A limited effort was made to determine ifrobust explanatory

models could be developed for crack spacing using linear regression analysis. However, the

results were not promising (low coefficient of correlations) and no further effort was devoted to

this activity. Use of empirical analysis was not part ofthe scope ofthe study and the results are

therefore not reported here.

Effect of Cracking on Ride

The effect oftransverse cracking on ride is shown in figure 28. No clear trends are

apparent. This is possibly due to not considering the influence ofinitial roughness. It should be

noted that previous studies have indicated that initially smooth (as-constructed) CRC pavements

generally remain smooth, and rough (as-constructed) CRC pavements tend to become rougher

with time.

33
.... .. • •

•• • • • • • •

• .... • ....

••• ...

• • .. • • • • ••

• ..... l ... # •

•• • .. • • • •

•• •... • • •

• • • •

•

3.00

2.50

2.00

E

o!!!:

E 1.50

1.00

0.50

0.00

0.00 0.50 1.00 1.50

Average Crack Spacing, m

2.00 2.50 3.00

Figure 28. Effect of crack spacing on JR!.

Effect of Crack Spacing on Deflections

To determine the relationship between crack spacing and deflections as measured by the

falling-weight deflectometer (FWD), average crack spacing was plotted versus load transfer

efficiency and the ratio ofthe edge deflection and the corresponding interior deflection for

sections having FWD data in the database, as shown in figures 29 and 30, respectively. No clear

trends in the data can be observed. It is seen that most ofthe sections exhibited load transfer

efficiency at cracks of 90 percent or more. The ratios ofthe edge deflection and the

corresponding interior deflection ranged from 1 to about 2. The variability within the range is

possibly due to the time oftesting (curling effects), slab warping effects, and the type ofshoulder.

Summary

CRC pavement behavior is characterized by crack spacing (average crack spacing and other

crack spacing-related statistics) and CRC pavement performance is characterized by the number

oflocalized failures (patches and punchouts), ride quality, and structural capacity (as determined

by FWD testing). For the GPS-5 experiment, it appears that cracking data must be obtained by

manual surveys and actual crack mapping must be done to allow appropriate crack spacing

statistics to be determined. Also, the GPS-5 monitoring plan must include a visual survey of 5- to

8-km lengths ofthe project to allow reliable determination ofthe number oflocalized failures per

kilometer. Crack width data are also important and should be collected over a representative

subsection ofthe monitored length.

34
: ~<> ~. v V <> <>

<> <> <> <>

<> <>¢¢ <>

<> <> <> <> <> <> 6

<> <> <> <> <>

<> <>

<>

<>

<>

<>

0.9

0.5 1.0 1.5 2.0 2.5 3.0

0.8

0.0

III

o

iii

ij' 0.95 I::

.!I!

.\,1

iIi

...

Q)

-

VI

I::

III

16 0.85

.3

Q)

Cl

III

...

Q)

>

«

Crack Spacing, m

Figure 29. Average load transfer efficiency at cracks versus crack spacing.

5

<>

<>

<> v <> ~<>

<9<> <> <> <D <> <>

<><> <><> <><>

<> <>

(l¢ ¢O A~ <> <> <>

o

0.0 0.5 1.0 1.5 2.0 2.5 3.0

Crack Spacing, m

Figure 30. Ratio ofmaximum edge and interior deflections versus crack spacing.

35

CHAPTER 4. ANALYSIS OF WELL AND POORLY PERFORMING SECTIONS

In order to further understand the performance characteristics of CRC pavements, analysis

was conducted of "exceptionally" well and poorly performing CRC test sections. It was expected

that such an analysis would help identify some ofthe key design and site factors that affect the

long-term performance of CRC pavements. To conduct this analysis, two groups ofsections were

formed using data from the GPS-5 experiment. These groups were called "Well Performing

Sections" and "Poorly Performing Sections." The set of criteria used to define well and poorly

performing sections is given in table 8.

Table 8. Criteria for identification of well and poorly performing sections.

Criterion Well Performing Sections Poorly Performing Sections

Years in Service 20 or more 15 or less

IRI, m/km < 1.5 Not Considered

Severe Cracking None Yes

Punchouts & Patches None Yes

Using the above criteria, the 85 CRC pavement sections were tested. Ten sections were

identified as Well Performing Sections and 13 sections were identified as Poorly Performing

Sections. To find common characteristics among well or poorly performing sections, the

following factors were considered as possibly affecting CRC pavement performance:

• Design parameters

- Design percent longitudinal steel

- Depth to reinforcement

- Longitudinal bar spacing

- Transverse bar spacing

- Reinforcement placement method

- Mean slab thickness

- Slab elastic modulus

- Base type

- Base thickness

- Base elastic modulus

- Subgrade type (coarse/fine)

- Soil k-value

- Outside shoulder type

• Climatic conditions

- Climatic region

- Average annual freeze index

37
- Annual precipitation

- Average daily temperature range

• Traffic loading data

- Traffic opening date (age as tested)

- Cumulative 80-kN ESAL

• Distress data

- Average crack spacing from manual and PADIAS crack surveys

- Average IRI

- Load transfer efficiency

Tables 9 and 10 present lists ofwell and poorly performing sections together with the key

complementary data. The key data were compared on a case-by-case basis for the well and poorly

performing sections and for all sections ofthe GPS-5 experiment. The results, as plotted, are

given in the following figures:

Figure 29 - Comparison of design percent longitudinal steel.

Figure 30 - Comparison of depth to reinforcement.

Figure 31 - Comparison oflongitudinal bar spacing.

Figure 32 - Comparison oftransverse bar spacing.

Figure 33 - Comparison ofslab thickness.

Figure 34 - Comparison of concrete modulus of elasticity as tested.

Figure 35 - Comparison of base thickness.

Figure 36 - Comparison of base modulus of elasticity as backcalculated.

Figure 37 - Comparison ofsubgrade k-value as backcalculated.

Figure 38 - Comparison of annual air freezing index.

Figure 39 - Comparison of annual precipitation.

Figure 40 - Comparison of daily temperature range.

Figure 41 - Comparison of crack spacing.

Figure 42 - Comparison ofIRI values.

Figure 43 - Comparison of age.

Figure 44 - Effect of climatic condition.

Figure 45 - Effect ofreinforcement placement.

Figure 46 - Effect of base type.

Figure 47 - Effect ofsubgrade type.

Figure 48 - Effect ofshoulder type.

No clear trends are readily apparent for well and poorly performing pavements. For the

numerical parameters discussed above, the two-sample t-test (with unequal variances assumption)

was utilized to determine ifthe group means for the parameters in question for well and poorly

performing groups were significantly different. The results indicated that the slab thickness and

the concrete modulus of elasticity were significantly different at a level ofsignificance of 0.05.

38
w

\0

Table 9. Lists ofwell performing sections and complementary data for sections

Section Design % Depth to Longitudinal Transverse Reinforcement Mean Slab E Slab E Slab Base Base 

ID Longitudinal Reinforcement, Bar Spacing, Bar Placement Thickness, Tested, Backcalculated, Type Thic

Steel mm mm Spacing, Method mm GPa GPa Treated! mm 

mm Granular

05-5803 0.61 101.60 101.60 406.40 Chairs 203.20 TB 

06-7455 0.56 101.60 165.10 1524.00 Chairs 213.36 32.04 54.00 GB 

10-5005 0.60 96.52 152.40 Mech 203.20 18.60 36.60 TB 

13-5023 0.60 99.06 152.40 Chairs 215.90 33.24 43.20 TB 

17-9267 76.20 165.10 1219.20 Chairs 203.20 42.89 43.30 TB 

31-5052 0.75 63.50 152.40 914.40 Chairs 203.20 25.67 62.20 TB 

37-5037 0.60 101.60 762.00 304.80 Mech 203.20 21.36 34.60 TB 

46-5020 0.59 63.50 165.10 1219.20 Chairs 203.20 27.56 34.50 TB 

48-5334 0.51 96.52 190.50 762.00 Chairs 203.20 34.97 37.50 TB 

51-2564 0.60 88.90 152.40 Other 203.20 24.80 29.60 TB 

Table 9. Lists ofwell performing sections and complementary data for sections (continued)

Section Subgrade k-value Outside Climatic Average Annual Average Age as ESAL Ave

ID Type Coarse/ Backcalculated, Shoulder Region Annual Precipitation, Daily Tested, Total Crac

Fine MPa/mm Type Freeze mm Temperature year (*1000) Spac

Index,oC- Range, °C

days

05-5803 C AC WNF 68.61 1336.00 11.88 21 1820 

06-7455 C 42.28 AC DNF 0.53 270.00 15.13 20 8971 

10-5005 C 78.31 AC WF 125.00 1160.00 11.64 20 5976 

13-5023 F 69.43 AC WNF 1.81 1266.00 11.24 20 21332 

17-9267 F 82.32 AC WF 564.89 925.00 10.65 23 16311 

31-5052 F 43.06 AC WF 573.94 734.00 11.47 20 5263 

37-5037 F 54.74 AC WNF 83.10 1175.00 13.43 24 12365 

46-5020 C 124.76 PCC(JRCP) DF 619.59 451.00 15.82 20 947 

48-5334 F 102.34 PCC(JRCP) WF 133.47 574.00 14.97 25 11754 

51-2564 F 90.31 PCC(JRCP) WNF 45.13 1178.00 10.23 22 11755 

LTE = load transfer effiCIency
+:-

o

Table 10. Lists ofpoorly performing sections and complementary data for sections.

Section Design % Depth to Longitudinal Transverse Reinforcement Mean Slab E Slab E Slab Base Bas

ID Longitudinal Reinforcement, Bar Spacing, Bar Placement Thickness, Tested Backcalculated, Type Thi

Steel mm mm Spacing, Method mm , GPa GPa Treated! mm 

mm Granular

09-5001 0.60 101.60 160.02 863.60 Chairs 203.20 36.69 44.90 GB 

17-5843 0.71 58.42 185.42 1219.20 Chairs 254.00 40.65 28.90 TB 

37-5826 0.65 76.20 152.40 762.00 Mech 203.20 28.42 40.70 TB 

39-5010 Mech 203.20 0.00 TB 

41-5021 0.51 109.22 165.10 1524.00 Other 274.32 22.91 41.50 TB 

48-5024 0.60 127.00 185.42 914.40 Other 254.00 0.00 65.10 TB 

48-5284 0.50 139.70 203.20 609.60 Chairs 279.40 0.00 39.00 TB 

48-5301 0.60 127.00 185.42 914.40 Chairs 254.00 0.00 46.60 TB 

48-5310 0.50 139.70 203.20 609.60 Chairs 279.40 0.00 34.60 TB 

48-5317 0.51 101.60 190.50 914.40 Mech 203.20 0.00 51.70 TB 

48-5323 0.61 114.30 203.20 914.40 Mech 228.60 29.28 38.10 TB 

48-5335 0.61 114.30 203.20 914.40 Chairs 228.60 34.97 28.90 TB 

54-5007 0.65 76.20 Chairs 203.20 21.88 24.00 TB 

Table 10. Lists of poorly performing sections and complementary data for sections (continue

Section Subgrade k-value Outside Climatic Average Annual Average Age as KESAL Ave

ID Type Backcalculated, Shoulder Region Annual Freeze Precipitation, Daily Tested, Total Cra

Coarse/Fine MPa/mm Type Index, °C-days rom Temperature years Spa

Range, °C

09-5001 C 33.40 AC WF 397.32 1243.00 12.18 15 15646 

17-5843 F 56.72 AC WF 547.61 820.00 11.42 6 4897 

37-5826 F 34.16 AC WF 95.08 1150.00 13.69 14 8239 

39-5010 F AC WF 428.82 980.00 12.58 13 2272 

41-5021 F 70.51 AC WN 27.22 1117.00 12.67 8 11588 

48-5024 F 85.31 AC WN 14.88 999.00 14.06 13 1522 

48-5284 C 83.95 PCC (JPCP) WN 47.59 969.00 12.58 9 1019 

48-5301 C 128.84 PCC (JPCP) WN 51.54 838.00 12.91 15 1765 

48-5310 F 94.68 PCC JPCP WN 44.44 946.00 13.57 10 2238 

48-5317 F 47.33 PCC JPCP WN 37.59 888.00 12.54 15 4426 

48-5323 F 61.15 PCC JPCP WF 139.09 566.00 15.26 15 9748 

48-5335 C 61.01 PCC(JPCP) WF 129.54 584.00 15.31 15 8914 

54-5007 F 50.01 PCC(JPCP) WF 312.86 1219.00 12.97 14 1751 
Poorly Performing All Sections

Sections

Well Performing

Sections

0.4 -1---

0.5 -1--

Q) 0.7 ,---------- -, Q)

enro 0.6 +---

c:

'5

:J

:t:

C>

c:

o

....J

'#. 0.3 +--- c:

.2>(/) 0.2 +--~

0.1 +---

9l O.O-J--- «

Figure 31. Comparison of design percent longitudinal steel.

E 120.0

E

c: 100.0 Q)

E

Q)

80.0

.Q

c: 'w

c::: 60.0

0

....

.l::

.... 40.0

a.

Q)

Cl

Q) 20.0

C>

9l 0.0 «

Well Performing Poorly Performing

Sections Sections

All Sections

Figure 32. Comparison of depth to reinforcement.

41
Poorly Performing All Sections

Sections

250.0 -.-------------------------,

di

.~ 200.0 ro +---

0.

00

ffi 150.0 +-- aJ

ro

c:

'5 100. 0 +--------j ::l

C)

c: .:l 50.0 +-----j

Q)

C)

0.0 +-~

« Well Performing

Sections

Figure 33. Comparison oflongitudinal bar spacing.

All Sections

-~-----------------------,

Poorly Performing

Sections

Well Performing

Sections

0.0 -

200.0

400.0

600.0

r-------------------~---------

I 1200.0 -,-----------------------,

I g> 1000.0 _

.[

Cf) 800.0

_________________________ _._J

Figure 34. Comparison oftransverse bar spacing.

42
E 250.0

E

ui 200.0 - m

c

..:.::

0 150.0 -

.0

m

Ci5 100.0

c

m

Q)

50.0 - Q)

C>

0.0 -

Well Performing

Sections

Poorly Performing

Sections

All Sections

Figure 35. Comparison ofslab thickness.

-----~-_._--_.. _------ .- --_.-._--_.._-------.._-- -----~~~~~~~~~~~---,

35 -r-------------------------,

-----------_.._--- ...-----------~~~~~~-----I

-1-~~~~~---------_.._.._--------------------I

m

a.. 30 C.9

"t:J 25 - Q)

+-'

Ul

20 Ul

m

J:J 15 - u;'" L1J 10 - Q)

Cl

5

«

0

Well Performing

Sections

Poorly Performing

Sections

All Sections

Figure 36. Comparison of concrete modulus of elasticity, Es1ab, as tested.

43
140

E 120 E

iii

III 100

Q)

c:

..lo::

u 80

Q) 60 III

ro

co 40 Q)

Cl

20

«

0

Well Performing Poorly Performing

Sections Sections

All Sections

Figure 37. Comparison of base thickness.

Poorly Performing All Sections

Sections

ro0. 7 ,-- ---,

C.9

-0Q) 6 .

iii

:; 5 u

ro

u

..lo::

u

ro

co

III

ro

2-- I'll

.c

W

Q)

Cl

0 -1----

« Well Performing

Sections

Figure 38. Comparison of base modulus of elasticity, Ebase, as backcalculated.

44
Poorly Performing All Sections

Sections

Well Performing

Sections

90.0 -r-----------------------,

80.0 +-~~~~~~~~~~~~ __~~~~~~_I

70.0 +--

60.04----

50.0 -

40.04----

30.0 -f-----~

20.0 +--

10.0 -

0.0 -

Figure 39. Comparison ofsubgrade k-value as backcalculated.

Poorly Performing All Sections

Sections

Well Performing

Sections

0+---

50 --\---,

150 --\---

100 +---

en 250 ,----------- -,

'i'

uo

200 --\---

'0

.£

Ql

LL

ro:::J

c:

c:

<{

Ql

C)

!!!

Figure 40. Comparison of annual air freeze index.

45
E 1000

E 900 c:-

0 800

+:i

+'

ro 700

"6..

°

0 600

0- 500

ro 400 :::J

c:

c: 300

«

Q) 200 C>

e:! 100

« 0

Well Performing

Sections

Poorly Performing

Sections

All Sections

----~~-~-~-~------------_-----!

Figure 41. Comparison of annual precipitation.

,--------~------ - - ---- -------------------------- - - -------------~~--~-------~-----------.

u0 14 -

ai

Cl

c: 12

ro

0:: 10 :::J

+'

e:! 8

Q)

a.

E 6

4 °ffi

Cl

Q) 2 Cl

e:!

0-

« Well Performing

Sections

Poorly Performing

Sections

All Sections

------------------------------ ----------------------~

Figure 42. Comparison of daily temperature range.

46
1.4 -.-- -----,

E 1.2 +----------

d)

r::: 1.0-1---_ .[

C/) 0.8 -1--

o 0.6-1---- 5

Q) 0.4-1----

0.2-1----

O.O+--

Well Performing

Sections

Poorly Performing

Sections

All Sections

Figure 43. Comparison of crack spacing.

~------------------- -------..._----------------

2.0 ...,.------------------------,

1.8-1---

1.6 +----------

~1.4+----------­

E 1.2 +----------

it 1.0 -1--

0.8

0.6-1----

« 0.4-1----

0.2-1--

0.0 -+--

Well Performing

Sections

Poorly Performing

Sections

All Sections

Figure 44. Comparison ofIRI values.

47
25.0

20.0 "-co

Q)

>.

-g 15.0 +J

10.0

l/l

co

Q)

C> « 5.0

0.0

Well Perfonning

Sections

Poorly Perfonning

Sections

All Sections

Figure 45. Comparison of age.

60

--------------------------~

-------------------------------~~-

-1-__-,--------,..-__-------1

30 -I~--------------------__I

20 -

O+----'------,----'------r---'--

50 o

en

§ 40

1:5

Q)

C/)

-

o

C

Q)

cf. 10

Dry-Freeze Dry-No Freeze Wet-Freeze Wet-No Freeze

oWell Performing Sections • Poorly Performing Sections

Figure 46. Effect of climatic region.

48
80 -,------------------------,

70 +---~-___,r_____---.-------.-.--- ---

en 60

c::

2 50

()

40

30

c::

20

rf. 10

o -1-----1--

Chairs fv1echanically Other

o Well Performing Sections II Poorly Performing Sections

Figure 47. Effect ofreinforcement placement type.

100 ,--------------------------,

90 +-------------------jr----

80 -t----------------I

70 +--.----------------1

o

13 60 +--.----------------1

50 +--.----------------1

b 40 +--.---------------1

C

Q) 30+--------------------1

20+--------------------1

a.. 10+-----r-----.====---------I

o -\------&.---

Granular Base Treated Base

lowell Performing Sections II Poorly Performing Sections I

Figure 48. Effect of base type.

49
80 .--------------------'-----------,

70 -1----------------------

~60 -1-------------------..---

ui

c

~50 -1----------------

~40 +------,---...,.-----------l

-o

C 30 -1--------1

CD

20 -1--------1

a..

10 -1--------1

o -1----'''-----

Coarse Grained Subgrade Fine Grained Subgrade

o Well Performing Sections II Poorly Performing Sections

Figure 49. Effect ofsubgrade type.

80 ,....------------------------,

70 +--_--~~----------------l

tJ) 60 +----1

C

50 -1-----1

U

40 +----1

-

Co 30 +----1

CD

20 -1---1

CD

a.. 10 -/-__-1

o -1-_---1. _

AC Shoulder PCC Shoulder

[0 Well Performing Sections III Poorly Performing Sections I

Figure 50. Effect ofshoulder type.

50
This indicates that for the GPS-5 sample analyzed, the sections with relatively thinner concrete

slabs and stiffer concrete may result in better performance. The observation related to slab

thickness appears to contradict expectations. This may possibly be due to the confounding effects

oftraffic loading.

Summary

Although the statistical analysis was inconclusive overall, there is evidence among poorly

performing sections that have developed high-severity cracking and punchouts early in their

service life that these sections also had the following common characteristics:

• Larger crack spacing.

• Greater depth to reinforcement.

• High value ofmean slab thickness.

• Low values of elastic moduli for slab and base layer.

• Low k-value for subgrade.

Similarly, well performing sections appear to have the following common characteristics:

• Smaller crack spacing.

• Lower IRI (selection criteria).

• Shallow depth to reinforcement.

• Thinner and stronger slab.

• Stiffer base and subgrade layers.

51

CHAPTER 5. SUMMARY AND RECOMMENDATIONS

The study reported here was conducted to determine if currently available data from the

LTPP GPS-5 experiment can be used to understand the development of crack spacing in CRC

pavements and to analyze the effect of crack spacing and other design and site parameters on CRC

pavement performance. The report has presented the characteristics ofthe GPS-5 data and has

presented the results ofvarious analyses conducted to identify the key factors that affect the

performance ofCRC pavements.

Overall, the study has not resulted in any conclusive findings on cause and effect

relationships between key design and site parameters and performance attributes. As indicated

previously, there exist several major constraints for performing conclusive analysis of

performance ofCRC pavements. These constraints include the following:

1. Lack of data on ambient weather conditions during the first few days after concrete

placement.

2. Lack ofreliable traffic loading data for each test section from the day of opening to

traffic.

3. Lack ofindividual crack spacing data and distress maps.

4. Lack of data on concrete coefficient ofthermal expansion and crack width.

5. Lack ofsignificant distresses at the test sections. Very few sections exhibited

localized failures and high-severity cracking. Also, most ofthe sections that were

overlaid did not exhibit localized failure or poor ride. Thus, it is difficult to relate

failure ofthe overlaid sections to specific attributes ofthe test sections.

6. Previous studies have indicated that there is a strong relationship between crack

spacing, concrete strength, and percent steel. No such relationship was apparent

for the GPS-5 sections. It is very likely that this is due to the biased sampling with

respect to slab thickness and percent ofsteel used.

The analysis ofthe "exceptionally" well and poorly performing test sections also failed to

provide definitive information regarding long-term performance ofCRC pavements, although

some general observations could be identified.

Previous analysis and data presented in the report have indicated that CRC pavements

generally provide a good ride even after many years ofservice. The ride, as measured by the IR!,

was generally smooth (lR! less than 1.5, typically) for most ofthe GPS-5 test sections.

Previous studies have also indicated that development of early crack cracking patterns in

CRC pavements is significantly affected by ambient weather conditions at the time of

construction. As such, design variables such as percent steel reinforcement, concrete strength, and

subbase type appear to be secondary in nature. These studies have also shown that long-term

53
cracking appears to be affected by percent steel, age, traffic loading, and concrete strength. The

cracking development slows (stabilizes) after about 3 to 4 years after construction.

In order to make the GPS-5 test data more useful, it is strongly recommended that future

distress surveys include a survey of 5 to 8 km ofthe pavement ofthe appropriate project to

identify the amount oflocalized failure. The 152-m lengths ofthe GPS-5 test sections are

considered too small to provide reliable data on localized failures.

CRC pavements have the potential to provide long-term low-maintenance service life as

evidenced by the many well performing sections in the GPS-5 experiment. It is expected that as

additional data become available, it will be possible to identify the specific factors and

mechanisms that affect the performance ofCRC pavement. This will allow improvements in the

design and construction practices for CRC pavement.

54
REFERENCES

1. Suh, YC., Hankins, K., and McCullough, B.F., Early-Age Behavior ofContinuously

Reinforced Concrete Pavements and Calibration ofthe Failure Prediction Model in the

CRCP-7 Program, Report No. 1244-3, Center for Transportation Research, University of

Texas at Austin, 1992.

2. Zollinger, D.G., and Barenberg, E.J., Continuously Reinforced Concrete PavementsPunchouts and Other Distresses and Implicationsfor Design, Report No. FHWA/IL/UI227, Federal Highway Administration, Washington, DC, 1990.

3. Tayabji, S.D., Zollinger, D.G., and Gagnon, 1.S., Performance ofCRC Pavement:

Volume III- Analysis and Evaluation ofField Test Data, Report No. FHWA-RD-94-180,

Federal Highway Administration, McLean, VA, 1998.

55