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APPENDIX B ANNOTATED BIBLIOGRAPHY

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APPENDIX B-ANNOTATED BIBLIOGRAPHY Abbo, E., "The Influence of Heavy Vehicle Dynamics on Rigid Pavement Response," Massachusetts Institute of Technology, 1987. The purpose of this paper is to develop a methodology to analyze rigid pavement response to moving, dynamic vehicle loads which may be used to predict pavement performance. Current models of vehicle-pavement interaction employ simplified models of vehicle loading, such as a static load. However, instantaneous dynamic vehicle loads may be considerably higher than static loads, and thus dynamic loading can have a considerable impact on rigid pavement performance. The paper investigates the influence of heavy truck vehicle dynamics on rigid pavements. In order to predict the forces at the road-tire interface, full non-linear models were used to describe the behavior of articulated vehicles traversing rigid pavements. Non-linear leaf-spring suspension and tire models were used. Following a review of rigid pavement models, we selected and modifiect PMARP (Purdue Method for Analysis of Rigid Pavements), to couple with our vehicle model. Part of the modifications made to PMARP included addition of temperature gradient and moisture gradient effects and performance submodels. The pavement failure and performance models include fatigue cracking, pumping, load transfer decay, joint faulting, slab roughness, and present serviceability index. The mode! loads a series of slabs with the dynamic tire forces of all the axles of the vehicle as it traverses the slabs. The tire force profiles are generated from the vehicle mode} for each seasonal value of pavement joint-fault magnitude, slab roughness and warping. Since the pavement experiences the effect of dynamic loading of all the axles of the vehicle, we express our damage results In terms of vehicle equivalency factors. The final part of the study discusses the effects of varying vehicle parameters on road damage. The parameters examined include suspension type, friction parameters, tire pressure, axle spacing and suspension spring constants. Al-Omari, B. and M. I. Darter, "Effects of Pavement Deterioration Types on IRI and Rehabilitation," Illinois Department of Transportation, 1993. A study of the relationships between PSR, {R} and selected pavement distress types was conducted. A predictive mode! was developed between present serviceability rating (PSR) and the International Roughness Index (IRI). Relationships between IRI ant} selected asphalt `_ , . ~ ~ . . . . .. ~ . . ~ , .. .. pavement and ~omtecl concrete pavement Distress types were developed. come ot the distress types have stronger effects on {RT than others, and the severity level of these distresses is also very important. The relationship of {RT to critical levels of rehabilitation was evaluated. It was found that as distress amounts increase in number and in severity, the TRI increases also. However, a pavement could be relatively smooth and still have a significant amount of distress. If a pavement was not rehabilitated until it became relatively rough (Iow PSR or high {RI), the B-!

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resulting rehabilitation cost might be very large. While the longitudinal profile (as measured by the {RI) may be a good indicator of the highway user acceptance of the pavement (as indicated by the correlation with user pane! ratings), it may not be a good indicator of when the pavement should be rehabilitated from a structural viewpoint and from a rehabilitation cost standpoint. Thus, it is not believed possible to develop a cost~ffective rehabilitation program for pavements relying only on the longitudinal profile (or TRI). Visible distress is an important aspect to proper selection of tiring and type of rehabilitation techniques. It is recommended that the HPMS utilize both the IR] and selected pavement distress types as trigger values for more consistent and realistic results in predicting future rehabilitation needs on the nation's highways. Al-Omari, B. and M. I. Darter, "Relationships Between TR! and PSR," Civi'Eng~neenng Shtdies, Number 69, Federal Highway Administration, 1992. This report documents the work accomplished on a study to develop relationships between the International Roughness Index (IRI) and the Present Serviceability Rating (PSR) for pavement types includes in the HEMS database (flexible, rind and composite pavement types). PSR is defined as the mean user pane} rating for rideability. Relationships between TRT and PSR were analyzed for the states of Louisiana, Michigan, New Jersey, New Mexico, and Ohio which were found in the NCHRP Project 1-23 database, plus some additional data obtainer} from Indiana. Data for all six States were entered Into a SAS data set and the foBow~ng nonlinear mode! was found to best fit the boundary conditions and the actual data: PSR= 5 ~ eta ~RI' Regression analysis was conclucted for all possible sets of data considering different States and - ~ . ~ ~ ~ =~ ~ ~ ~ a~ ~ aq it- ~ ~ - ~ ~ ~ -~ ~ ~ pavement types. it was deternuned that there was no significant difference between the models for different States, and pavement types, thus the following mode! is recommended: PSR = 5 ~ et~004~ me where IRI is in units of in/mile, or: where {RI is in units of mm/m. PSR = 5 ~ e<~26 ~ ~ Alexander, M. L., "Profile Index Requirements for Asphalt Concrete Pavements," Number CA1~-85/17, California Department of Transportation, 1985. The California profiIograph was used to evaluate pavement smoothness before and after placing subsequent layers of asphalt concrete (AC) pavement. An improvement in the profile index (Pl) can normally be expected with each layer of AC; however, the relative amount of improvement is influenced by the PI of the surface being covered. The data also indicates that pavement reinforcing fabrics can have a detrimental effect on He PI of the first layer of AC placed over the fabric. B-2

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American Association of State Highway and Transportation Officials, "Summary Results of the 1987 AASHTO Rideability Survey," Prepared by the Highway Subcommittee on Construction Washington D.C., 1987, pp. 17-87. The 1987 AASHTO Rideability Survey involved all member states is summarized in this informational report. The focus of the survey was on distinguishing between rideability specifications and bump specifications, determining the roughness measuring equipment used and to determine the use of incentives and disincentives. The results of the survey have been tabulated and a report and comments reflecting the results presented are in the report. American Concrete Pavement Association (ACPA), "ACPA Rideability Guide Specification," New ACPA Guidelines, 1988, pp. 2-88. This document is a specification for measuring the roughness of a concrete pavements using a California ProfiIograph. American Concrete Pavement Association (ACPA), "Constructing Smooth Concrete Pavements," Technical Bulletin TB-006.0-C, 1990, pp. 4-90. Many factors influence concrete pavement smoothness during design, construction and measurement. It is important to make appropriate design decisions, maintain attention to detail during construction and follow uniform profile measurement procedures to accurately determine and evaluate the overall riding quality. This technical bulletin provides guidance for the construction of smooth concrete pavements. The bulletin focuses on the Californ~a-type and the Rainhart ProfilO=~raphs comparing the two equipment. The impact of design, construction equipment and techniques on pavement smoothness or ride quality is presented in this bulletin. ARE, Inc., Technical Memorandum from Eric D. Moody, Subject: "Development of Pay Factor Tables for Arizona DOT Flexible Pavement Smoothness Specification," Project No. AZ-60, May 31, 1990. There have been many theories developed for generating nav factor tables. This memorandum of -o r --A illustrates two techniques for generating pay factor tables have been mentioned. Although the two techniques are applied in totally different manners, they are both based on the general concept of the AASHTO Guide. The first technique discussed is based on "Life Cycle Cost Analysis" of pavements that have different initial roughness levels but otherwise are identical. The second technique mentioned involves calculating the number of IS-kip ESALs the as constructed pavement can be expected to carry and comparing that number to the number of IS-kip ESALs the design pavement is expected to carry. Ashmore, S. C. and H. C. Hodges Jr., "Dynamic Force Measurement Vehicle (DFMV) and its Application to Measuring and Monitoring Road Roughness," Vehicle, Tire, Pavement Interface, ASTM STP 1164, American Society for Testing and Materials, 1992, pp. 69-96. A method for measuring He longitudinal profile of a highway or off-highway surface is given. As a paper presented at a "Vehicle, Tire Pavement Interface" meeting, this profile method is of B-3

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particular interest to those involved in the study of vehicle response, as well as pavement roughness. The advantages and uses of a wave-number spectrum presentation of road roughness is discussed. Asnani, S., K. Ksaibati, and T. I. Al-Suleiman, "Consistency of Roughness and Rut Depth Measurement Collected with 11 South Dakota Road Profilers," Transportation Research Record, Number 1410, Committee on Surface Properties-Vehicle Interaction, 1993, pp. 41-51. Pavement roughness has long been recognized as a primary indicator of pavement performance. To provide accurate and reliable roughness measurements, the South Dakota Department of Transportation (SDDOT) designed and constructed a profilometer system in 1982. This system was later improved and enhanced by adding more sensors for rut measurements. The increased interest in the road profiler resulted in the establishment in 1989 of the South Dakota Road Profiler User's Group (SDRPUG). During the Third Annual SDRPUG meeting in Minnesota in 1991, international roughness index and rut depth data were collected with 11 road profilers on 4 different pavement surfaces. These selected pavement types were concrete, bituminous, concrete-bituminous over concrete, and bituminous over concrete. Each road profiler was run three times over each test section. The collected data were then reduced and analyzed statistically. The main objective of the statistical analysis was to determine whether the differences in roughness and rut measurements obtained with the 11 road profilers were statistically significant. The experiment and the statistical analysis were described in detail. In addition, specific recommendations are provided for the need to establish calibration procedures to ensure consistency in roughness and rut depth measurements obtained nationwide. Bertrand, C. B., "Automated Versus Manual Profilograph Correlation," Transportation Research Record, Number 1410, Committee on Surface Properties-Vehicle Weight, 1993, pp. 67-79. The Texas Department of Transportation (TxDOT) has attempted to correlate the outputs of the automated Cox profilograh, the automated McCracken profilograph and a TxDOT manual McCracken profilograph. The evaluation process was precipitated by calls from construction engineers within the TxDOT highway agency and paving contractors working within Texas. Both the state and contractor personnel were requesting the use of the automated profilograph. The results of the evaluation process were as follows. The Cox automated profilograph used a filter setting number of 5, which represents the attenuation of 2.2 It (0.067 m) and less, whereas the McCracken model used a data filter cutoff frequency of 2.5 It (0.76 m). The profilograms from the TxDOT manual profilograph were reduced by two different interpreters. Both of the automated versions of the profilograph were slightly more repeatable than the interpretation of the manual profilograph. The automated profilographs showed very close correlation with the manual profilograph on the smooth, medium, and rough sections of asphalt concrete pavement and on the rough sections of continuously reinforced concrete (CRC) pavement. The automated profilographs deviated from the manual profilograph output on the smooth-section CRC pavement. This deviation was from 0.5 to 2.0 (0.789 to 3.16 cm) PI counts smoother (lower) than the output of the manual profilograph. B-4

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Bertrand, C. B., "Field Evaluation of the Auto-Read Version of the Face Dipstick as a Class ~ Profiling Device," Number 890332, University of Texas-Austin, Center for Transportation Research, 1990. The Federal Highway Administration has producect a Highway Performance Monitoring System Field Manual as a guideline for the individual States. The Field Manual includes an Appendix which describes the proper calibration and reporting procedures for pavement roughness monitoring. The individual States are required to calibrate all roughness instrumentation and to report that roughness in terms of the International Roughness Index (IRI). This paper details an evaluation effort sponsored by the Texas State Department of Highways and Public Transportation's Maintenance and Operations Division, Pavement Management Section. The evaluation concentrates on the field performance of the auto-read version of the Face Dipstick. This instrument is one of the Class ~ profiling devices identified in the Appendix mandate. All of the lower classifications of roughness monitoring instruments used by the States must be calibrated against a Class ~ device. The Dipstick was chosen by the Texas SDHPT because it was believed that it would be a cost effective and reliable substitute for the rod and level survey, which is also listed as a Class ~ profiling instrument. This paper describes concerns regarding the operation of the auto-read version of the Face Dipstick and the manufacturer's responses to those concerns. The field test sites utilized In the comparisons are described. The performances of two incliviclual Dipsticks against each over as weD as against Rod and Level surveys are described. The conclusions reached upon completion of the Dipstick evaluation are Included. The main conclusion reached is that in its present configuration, the auto-read version of the Face Dipstick is unreliable and should not be considered a Class ~ profiling device. Finally, recommendations for He Dipstick's future use based on its field performance are described. These recommendations are baser! on He use of Dipstick In the manual read mode of operation. Bertrand, C. B. and R. Harrison, "Evaluation of a High-Resolution Profiling Instrument for use in Road Roughness Calibration," Transportation Research Record, Number 1291, Transportation Research Board, 1991, pp. 93-105. Response-type roughness measuring devices, now commonly used throughout the world to monitor the condition of low volume roads, require careful calibration to ensure the accuracy of their measurements. Yet there is no consensus regarding the most appropriate instrumentation for such calibration. A recent World Bank publication, reporting the findings of a series of experiments in a number of countries, proposed a hierarchy of roughness measuring instruments, the most accurate of which (termed Class I) might be used for the calibration of response-type instruments (most of which are termed Class my. Included among these Class ~ instruments is the Face dipstick, an inexpensive high-resolution profiling devices whose features commend it for application on low-volume roads, but whose applicability for such use has not yet been properly demonstrated. By comparing two Class ~ profiling instruments for potential use in road roughness calibration, accepting the classification scheme established by the World Bank, it was found that the Face dipstick, in its manual form, is a fast, accurate, and cost-effective alternative to other methods, including the rod-and-level method. B-5

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Bertrand, C. B., R. Harrison, and B. F. McCullough, "Evaluation of FHWA Requirements for the Calibration of Pavement Roughness Instrumentation. Final Report," Number TX-91+969- 2F; Res. Rept. 969-2F, Texas University-Austin, Center for Transportation Research, 1990, 78p. The Federal Highway Administration (FHWA) has produced a Highway Performance Monitoring System Field Manual as a guide to the individual states. The Field Manual contains an Appendix J which describes and specifies the proper calibration and reporting procedures for pavement roughness measurements. The Texas State Department of Highways and Public Transportation's Maintenance and Operations Division, Pavement Management Section, was responsible for compliance with the Appendix J mandate by the State of Texas. The Center for Transportation Research (CTR) was contracted with to make certain Texas was in compliance with the FHWA's Appendix J procedures. This report details the procedures used for the selection of the nine specified calibration sites and how these sites were marked and laid out and includes details of how the Class I instrument's surface profile and the resulting IR! statistics were determined. The roughness monitoring instruments used In Texas and their outputs are described. Regression plots by wheel path for both first and second degree fits are presented for each pavement roughness monitoring instrument. A set of conclusions based on CTR's experiences and the resulting concerns over some of the procedures outlined in Appendix J are presented. Finally, recommendations and topics for possible future research are presented. These recommendations and topics are based on the findings of this evaluation effort and attempt to address areas in Appendix J where more specific instructions are needed to truly standardize the national pavement roughness calibration procedures and the resulting roughness statistics. Bester, C. J., "Effect of Pavement Type and Condition on the Fuel Consumption of Vehicles," Transportation Research Record, Number 1000, pp. 28-32. The effect of pavement type and condition (roughness) on the rolling resistance of vehicles is investigated. By means of the relation between the energy requirements and the fuel consumption of vehicles this effect is used to predict the fuel use on different pavements. It is found that, except for gravel surfaces, pavement type has a minor effect on fuel consumption. Roughness, however, correlates strongly with rolling resistance and therefore with vehicle fuel consumption. This is important for the economic justification of major road maintenance projects. Bhandari, A. S., and K. C. Sinha, "Optimal Timing for Paving Low-Volume Gravel Roads,t' Transportation Research Record, Number 702, 1979, pp. 28-32. This paper examines the economics of upgrading low volume gravel roads with particular emphasis upon construction postponement. The concept of break-even analysis is re-examined and a case presented for consideration of construction deferment in light of the opportunity cost of capital. This consideration is particularly important for developing countries where capital is scarce and the opportunity cost high. Simplified expressions are developed to determine both the break-even year and the optimal year in which to pave a given gravel road. Their application is illustrated by means of a numerical example. B-6

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Brickman, A. D. and I. C. Wambold, "An Amplitucle-Frequency Description of Road Roughness," Highway Research Board Special Reports, Number 116, 1970, pp. 53-67. This paper deals with a method for reducing roughness obtained from a continuous-output road profiIometer to a compact and useful form for highway engineers. It is assumed that a voltage signal representing vertical irregularities in the road surface as a function of distance has been recorded on magnetic tape. An analog method is describer! for processing this signal and reducing the roughness description of the road to a simple table relating roughness heights and wavelengths. Analog computer requirements are stated for the proposed signal-processing method. Results obtained by this method are presented for both ideal and actual road profile examples. The development of the surface dynamic profiIometer (SDP) has made it possible to obtain a magnetically taped record of any road surface profile in the direction of vehicle travel. For a given section of road, this record is a randomly varying analog voltage that represents true road roughness within the accuracy limitations of the SDP system. Having obtained a profile record, the highway engineer is faced with the problem of transforming this random signal into an index, graph, or set of numbers he can use to specify quantitatively the roughness of the road. This report describes a practical method for analyzing SDP records and for reducing each of these records to a simple form usable in highway operations. Brokaw, M. P., "A 5-Year Report on Evaluation of Pavement Serviceability with Several Roadmeters," Highway Research Board Special Repoffs, Number 116, 1970, pp. 80-91. This paper reports on an evaluation of results of pavement serviceability tests macle with the PCA road meter and with modifications of the original road meter developed by several states and provinces. Results of calibrations with serviceability ratings or serviceability indexes from ~ sources are shown. Repeatability tests are reported from 7 sources, along with tests by the original road meter over the same site throughout a 5-year period. The react meter ant its modifications rank with the AASHO profiIometer in ability to relate with serviceability ratings. Variations in measured roughness resulting from changes in wind velocity, air temperature, automobile speed, mechanical factors within road meters and test automobiles, and seasonal fluctuations caused by frost action are reported and discussed. Effects of wind velocity and direction, as related to direction of test car travel, and air temperature have a distinct effect, and the magnitude indicates that serviceability measurements to be used in extended studies of pavement behavior in conjunction with traffic loading should be Inane during a limited period between fuB recovery (as late as July or August) and the onset of the next winter. The simple digital counting system and unique computing method enable the PCA road meter to produce a statistic corresponding to roughness power spectrum. Data from 2 north central states are used to illustrate the usefulness of this attribute in analyzing serviceability indexes resulting from various treatments anti construction methods. Brown, D., "Evaluation of the PRORUT System," Public Roads, Vol. 53, Number 4, FHWA, March 1990, pp. 118-122. The development and evaluations which are describect of PRORUT, an inertial profiling system which can be used to measure and record various roadway characteristics, including the longitudinal profiles' ruding, and roughness levels of the two wheel tracks. Laser sensors and accelerometers are used to obtain the profile measurements In each wheel track. An IBM personal computer controls system operation and processes the data. The system was then B-7

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evaluated by the states (Georgia, Pennsylvania, Indiana), and the results are reported. The field tests demonstrated that PRORUT provided useful pavement profile information and that its output could be correlated to several response-type measurement systems. Bryden, I. E., "Development of a Specification to Control Rigid Pavement Roughness," Transportation Research Record 535, Transportation Research Board, 1975. During a recent study of factors influencing the riding quality of rigid pavements, compliance with the existing roughness specification was found not to ensure a smooth pavement. Because the 10-ft straightedge used to check the surface can detect only large bumps, the remaining undetectect roughness may result in unsatisfactory riding quality. This paper describes the development of a specification to ensure good riding quality in new pavements. The California profiIograph was selected as the measurement device because it provides detailed Information. Based on the results of a subjective pane} rating of pavement riding quality In New York State, a project average profile index of 12 inky and a daily average of 15 inky are allowed. A limit is also placed on the size of the individual bumps. These linuts ensure user satisfaction but can be met by paving contractors using current procedures and equipment. Responsibility for controlling roughness during paving is left to the contractor, and the state measures the quality of the completed pavement. To ensure compliance with the specification, the pavement received depends on the riding quality achieved. Development of the reduced payment schedule based on the cost of overlaying the pavement before the end of its clesign life is outlined. The years of service expected are related to the initial roughness by means of equations developed in the AASHO Road Test. Buchanan, I. A., and A. L. Catudal, "Standardizable Equipment for Evaluation of Road Surface Roughness " Highway Research Board Proceedings, Volume 29, Highway Research Board 1940. ~ , ~ This report considers existing methods and certain inherent characteristics of methods to measure highway surface smoothness or roughness. The standardizable equipment clescribed In this paper operates on He principle of the measurement of the vertical oscillation of a wheel suspension with respect to its supported frame. The equipment is in the form of a single-wheel semi-trailer, attachable to any towing vehicle, ant! is designed as a horizontal pendulum with the axle of the wheel placed at the center of the percussion. A special feature of the equipment is the Incorporation of a newly clesigned overrunning clutch integrator whose operating characteristics are remarkably constant. The performance characteristics and recommended standard operation procedure for the equipment are given in cletail. Many hundred nules of operation, without mechanical failure' indicate adequate mechanical design. It is easy to use and the data are obtained rapidly with it. B-8

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Budwig, J. L. "A Statistically Based Approach to Acceptance Utilizing the California Type Profilograph, California Test Method 526, and Computenzed Profilogram Reduction," Central Federal Lands Highway Division, Federal Highway Administration, Denver CO 80225, January, 1994. Since 1987, the Federal Lands Highway (FLH) Branch of the Federal Highway Administration (FHWA) has been evaluating acceptance of newly constructed bituminous pavements using California-type ProfiIograph measurements. California Test Method 526 ant! FISH T504, as well as other acceptance plans, have been employed in the evaluation. The purpose of this study was threefold. i) To determine whether operator trace reduction variability was too large for the method to be suitable for acceptance testing. ii) To decicle the type of acceptance plan to incorporate in the Standard Specification for Construction of Roads and Bridges on Federal Highway Projects (FP-921. iii) To evaluate two commercially available computer~zecl trace recluction systems. The study concludes that, when used In conjunction with statistical evaluation procedures, the test method is suitable for acceptance purposes and that computerized trace reduction is superior to manual reduction. The report also presents some fundamentals of statistical acceptance that are not widely known or understood by highway engineers. California Department of Transportation, "Operation of California Profilograph and Evaluation of Profiles," California Test 526, Division of Construction, Office of Transportation Laboratory, Sacramento, California, 1978, pp. 2~78. This document covers the operation of the California ProfiIograph. This includes procedures used for determining the Profile Alex from profiIograms of pavements and the procedure used to locate individual high points in excess of 0.3 inch are clescr~bed In three parts ~ Operation of the California ProfiIograph, Determination of the Profile Index and Determination of High Points in Excess of 0.3 inch) in this test method. California Department of Transportation, 'draining Course in Profilograph Operation, Care, and Certification," Presented at Transportation Laboratory, Division of Highways, August 9, 1973, pp. 21-73. The trairung course focused on the California ProfiIograph. The main topics covered include a detailed description of the California Profilograph, nature and purpose of test, processing and evaluation of profile information, care and maintenance of the equipment and certification of profile equipment. The California Test Method No. Calif. 526 is mentioned as a required testing method. Capper, M., "Keys to a Pavement Smoothness: A Paving Superintendentrs Viewpoint," Central Paving Corporation. The purpose of this paper is to acquaint He reader with some typical problems the construction industry must overcome to improve on pavement smoothness. The influence of certain factors on pavement smoothness such as construction practices, roadway geometry and paving equipment are cliscussect. Typical examples of modifications to paving equipment such as the redistribution of equipment weight and its impact on smoothness are also discussed. The B-9

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including a noncontact profile sensor, digital profile computation, and an array of computer software developments that will further enhance the inertial profiIometer's contribution to the pavement management process. for historical purposes Me paper also discusses the original development of the inertial profilometer at the General Motors Research Laboratories in the early 1960s and its introduction into the user community by K. J. Law Engineers, Inc. Spangler, E. B. and R. L. Rizenbergs, "Use of the Inertial Profilometer to Calibrate Kentucky Department of Highways Mays Ride Meter Systems," Transpoftation Research Record, Number 1196, Transportation Research Board, 1988, pp. 286-293. The National Institute of Standards and Technology (NIST), the Commonwealth of Kentucky Department of Transportation (DOT), and Surface Dynamics, Inc., joined in a project In the Commonwealth of Kentucky to calibrate five Kentucky DOT vehicle-mounted Mays Ride Meter (MRM) systems. In this project, a NIST-operated inertial profiIometer system was used to measure the elevation profiles of selected pavement test sections. The measured elevation profiles were used to compute the Standard Mays Ride Meter Index (SMRMI) values for each pavement test section. The computed SMRM! values were then used as reference values for the calibration of the actual Kentucky DOT MRM systems. The profiIometer was used to identify suitable pavement sections from test sites selected by the Kentucky DOT using an MRM system. The site selection process included sufficient repeat runs to establish a mean SMRM! value for each pavement and a standard deviation from that mean for the repeat runs. Six pavement test sites with the clesired SMRMI values and low standard deviations were selected. The five Kentucky DOT MRM systems were then driven over the selected test sites a number of times to determine a mean measured value and a stanciard deviation about that measured mean value for each system on each pavement test site. The test data from the profiIometer and the five Kentucky DOT MRM systems were used to develop a calibration equation and expected standard deviation for each of We MRM systems. The resulting calibration equations will be used by the Kentucky DOT to compute SMRMI values for each system. Included in the project was a correlation of the Ohio Department of Transportation inertial profiIometer with the NIST- operated inertial profilometer to establish the validity of using another identically constructed inertial profiIometer for the same calibration procedure. Spangler, E. B., R. [. Rizenbergs, I. To. Burchett, and D. C. Robinson, "Use of the Inertial Profilometer to Calibrate the Commonwealth of Kentucky Department of Highways' Mays Ride Meter Systems," Surface Characteristics of Roadways: International Research and Technologies, ASTM STP 1031, American Society for Testing and Materials, 1990, pp. 292-3020 In May 1987, a project was undertaken in Kentucky to calibrate five Kentucky Department of Highways vehicle-mounted Mays Ride Meter (MRM) systems. An inertial profiIometer operated by the National Bureau of Standards was used. Multiple elevation profiles were taken in order to evaluate the precision of the measuring method. Mean MRM Index values were computed for each MRM system. A second profiIometer was used to determine that equivalent calibrations can be expected from identical inertial profiIometers. A method was clevisec} by which real measurements by individual MRM systems can be converted into Standard MRM Index values. Additional research is neecled to determine the time stability of bow the MRM systems and the pavement sections used in calibration. B-66

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Spangler, E. B. and W. I. Kelly, "Integration of Inertial Profilometer in ODOT Pavement Management System. Final Report," Number FHWA/OH-87/005, Surface Dynamics/OH DOT/FHWA May 1987. Pavement roughness and ride quality Information, for the Ohio Department of Transportation (Ohio DOT) Pavement Management System, can be accurately computed directly from highway pavement profiles measured with the Ohio DOT Inertial Profilometer. The pavement ride quality information Includes Present Serviceability Rating (PSR) and PSR trigger values for non- routine maintenance. Pavement profiles measured with He Ohio DOT Inertial Profilometer have been used to calibrate the Ohio DOT Mays Ride Meter System, to analyze the Mays Ride Meter System performance, and to provide a link between that system and pavement roughness and ride quality information obtained from the Ohio DOT Inertial ProfiIometer. Pavement profiles measured with the Ohio DOT Inertial ProfiIometer have also been used to compute expected overlay material quantities and pavement ride quality on an Ohio DOT demonstration resurfacing project. Still, P. B. and P. G. Jordan, "Evaluation of the TRRE High-Speed Profilometer," Number TRRT [R922 Monograph, Transport & Road Research Laboratory, 1980, 45p. A high-speed laser-based profiIometer has been designed and developed at He laboratory to measure surface profiles of roads and airfield runways. This report describes the theoretical and experimental studies carried out to identify and to evaluate the factors that influence the accuracy of measurement of the profilometer. Detailed comparisons between test profiles measured by survey techniques and by the profiIometer are presented and discussecI. The factors that are of most importance in determining the profiIometer's accuracy of measurement are the imprecision in He determination of the non-colinearity of the laser transducers and In the transducers' calibration coefficients, together with the magnitude of the vertical temperature gradient across the profiIometer beam and the effect of surface texture. Phase and amplitude comparisons show good agreement between profiIometer and survey-measured profiles over the range of wavelengths that are of Interest in studies of riding quality. In operation, the profiIometer can measure road and runway profiles at speeds between 5 anct 80 kilometers per hour but with an error that Increases with speed. Facilities permit on-site analysis of the measured profiles ant! the measurement of surface texture if required. Stoffels, S. M., and R. L. [ytton, "Development of a Utility Evaluation for Nondestructive Testing Equipment Used on Asphalt Concrete Pavements," Transportation Research Record, Number 1117, Committee on Monitoring, Evaluation and Data Storage, pp. 134-142. Nondestructive testing of pavements has become a cost-effective and invaluable aid in determining the actual condition of pavement sections in a highway network. Because the number of nondestructive testing devices in use grows each year, the choice of the best method involves a complex comparison of alternatives involving the test equipment itself, the resulting data, and the available methods of analyzing the data provided. All of these factors are consiclered In a systematic way by the application of utility theory. A hierarchical weighing system is developeci using nonlinear utility curves. Each of the independent decision criteria is carefully cleaned. Weighing factors are developed using the Churchman-Ackoff technique. The analysis is performed with uncertainty obtained by using a beta probability distribution. The calculated results are expressed in terms of an expected value and a 95 percent confidence B-67

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interval. Five generic nondestructive testing devices are evaluated for use on asphalt concrete pavements for both project-level design and network-level planning. The characteristics of these devices used In the calculations were deliberately revised so that none of them represent actual commercially available equipment. The generic devices are used to demonstrate the evaluation technique. The formulated utility analysis framework can be applied to real devices. Furthermore, the analysis can be extended to other situations by appropriate modification of the criteria, weights, or utility curves. Stone, I., "Evaluation of the Teaser Road Surface Tester For Measuring Pavement Roughness and Rut Depth," Number FHWA-DP-88-072-OOX, U. S. Department of Transportation, 1988. This project was conducted to evaluate the performance of the Laser Road Surface Tester (RST) operated by Infrastructure Management Services (IMS). The work was done for Demonstration Project No. 72, "Evaluation of Equipment for Measuring Pavement Roughness and Rut Depth". The RST provides Quarter Car roughness, rut depth, and crack information. Correlations were made to the Georgia Modified Rainhart Mays Trailer (GMRMT), stringline rut depth measurements, and visual crack counts. A total of 17 test sites were selected for the correlation. These sites provided 56 Individual test sections encompassing a variety of pavement roughness levels and surface types. So far as possible, these sites were the same used In a previous study of other roughness measuring equipment, "Calibration Procedures for Roadmeters" Gil. A minimum of three repeat runs were made at each site. Each site was tested at two different times during the week for repeatability comparisons. Roughness data was obtained simultaneously with the GMRMT for comparison. String line rut depth measurements and visual crack counts were made for each flexible pavement test site for comparison to the Road Surface Tester. A good correlation was obtained for the GMRMT vs RST Quarter Car. The RST rut depth and manual string line measurements also correlated well. There was a poor correlation between visual crack counts and the RST crack count. The RST Quarter Car and rut depth readings are not speed dependent. They repeated well at speeds from 50 down to 20 mph. Suprenant, B., "Public Perception of Pavement Ride," CO DOH, July 1990. A panel of 30 to 40 people will be formed of volunteer employees from the Colorado Denartment of Hi~hwavs. Thev will be driven over a varie~tv of roads to e~tahli~h their opinions of pavement rideability. Their ratings will be correlated with smoothness measurements from a K. T. Law 8300 profiIometer, and will be used to establish categories of good, fair, and poor ride for the statewide pavement management system. Temple, W. H. and S. [. Cumbaa, "Serviceability Index Base for Acceptance of Jointed Concrete Pavements," Transportation Research Record, Number 1196, Transportation Research Board, 1988, pp. 251-256. This paper describes the techniques and relationships developed to design a Serviceability Index (SI)-based measurement system for acceptance of jointed concrete pavement construction in Louisiana. Pavement roughness statistics obtained from Mays Ride Meter equipment, a Surface B-68

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Dynamics Profilometer, and a Chioe Profilometer were regressed to establish an AASHO Road Test-based SI measurement system for concrete pavements with 20-foot joint spacings (ST ICE 20~. A 1986 pane! rating of 25 concrete pavements confirmed the validity of the model. Field testing of 50 newly constructed concrete pavement test sections provided a relationship between the ST JCP 20 mode! and profile statistics from rolling profilograph equipment and a lO-ft rolling straightedge. The research resulted in the development of a rational method of providing specification limits for profiIograph equipment that relate to pavement ricleability. Specification Omits In terms ot prone stansucs are provided to indicate the quality of paving necessary to construct a jointed concrete pavement with a Serviceability Inclex of 4.5. .. .. . . , ,. ~. .. .. . . ~. .. . .. ~. Todd, K. B. and B. T. Kulakowski, "Simple Computer Models for Predicting Ride Quality and Pavement Loading for Heavy Trucks," Transportation Research Record[, Number 1215, Transportation Research Board, 1989, pp. 137-150. ~, Increasing pavement damage caused by the increasing number of heavy trucks on today's highways has promoted concern about the dynamic pavement loads and the ride quality of trucks. So far, these concerns have been analyzed using only experimental studies and complex computer programs. This paper presents three possible simple truck models a quarter-truck, a half-single-unit truck, and a half-tractor semitrailer that can be used on personal computers to predict ride quality and pavement loading. Numerical values for the model parameters are suggested for possible standardization. Sample results are presented in the form of vertical acceleration frequency responses and root mean square vertical acceleration for ride quality and tire force frequency responses and dynamic unpact factors for pavement loading. The quarter- truck model overestimated both ride quality and pavement loading when compared to the half- single-un~t truck modele Uddin, W., W. R. Hudson, and G. Elkins, "Surface-Smoothness Evaluation and Specifications for Flexible Pavements," Surface Characteristics of Roadways: International Research and Technologies, ASTM STP 1031, American Society for Testing and Materials, 1990, pp. 224-236. The quality of smoothness of a newly constructed or overlaid pavement dictates the beginning of pavement management. Adequate acceptance testing procedures and specifications for pavement smoothness have not been available for flexible pavements. Smoothness specifications based on a lO-ft (3.05m) straightedge has a number of Mutations and is difficult to Interpret and administer. This paper describes the results of a comprehensive study of several different roughness measuring devices undertaken to select suitable device in order to develop and implement improved specifications for pavement smoothness. The candidate devices included the 690D Profilometer, Model 8300 Roughness Surveyor, Maysmeter, California Profilograph, and Rainhart Profilograph. In this study, the 690D Profilometer ranked highest in overall performance. The paper describes the benefits arid negative aspects of each type of equipment related to its use for surface- smoothness measurement and acceptance testing of newly constructed pavements and pavement overlays. The results are useful for any agency desiring to improve its smoothness measurement and acceptance testing procedures. B-69

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Vorburger, T. F., D. C. Robinson, S. E. Fick, and D. R. Flynn, "Calibration of Road Roughness Measuring Equipment. Volume I: Experimental Investigation," Number FHWA-RD-89-077, Federal Highway Administration, 1989. An extensive series of measurements was made of the performance of a particular mode! of an inertial road profiling system (IRPS), including evaluation of the noncontact height sensors, the accelerometers used to establish the inertial reference frame, the distance encoder, the associated Instrumentation, and the software used to convert the raw data into road elevation profiles. A field program was carried out which Included rod-anci-leve! surveys of several roads which were also profiled using the IRPS. The DIPS was also equipped with a commercial response-type road roughness measurement (RTRRM) system, with accelerometers to measure the vertical vibration of both the axle and the body of the vehicle, and with a linear potentiometer to measure the relative displacement between the axle and the body of the vehicle. Separate laboratory measurements were made to characterize the performance of the commercial RTRRM. Data collected with the RTRRM and with the auxiliary accelerometers and the linear potentiometer were compared with s~ngle-number ratings of road roughness as computed from He profiles measured using the TRPS. This report documents the measurements and analyses that were carrier! out In order to enable rational development of the calibration and testing procedures that are given In the companion report, FHWA-RD-89-07S, Calibration of Road Roughness Measuring Equipment, Volume H: Calibration Procedures. Vorburger, T. V., D. C. Robinson, S. E. Fick, and D. R. Flynn, "Calibration of Road Roughness Measuring Equipment. Volume Il: Calibration Procedures," Number FHWA-RD-89-078, Federal Highway Administration, 1989. A separate report (FHWA-RD-89-077, Calibration of Roact Roughness Measuring Equipment, Volume I: Experimental Investigation) documents an extensive series of measurements of the performance of a commercial inertial road profiling system PEPSI and a commercial response- type road roughness measurement (RTRRM) system. Based upon the results of these measurements and upon an analysis of the operation of such equipment, calibration and testing guides, given in the present report, were developed to assist users in assessment of DIPS and RTRRM functionality and operating performance. Walker, R. D. and W. R. Hudson, "Practical Uses of Spectral Analysis with Surface Dynamics Road Profilometer," Highway Research Record, Highway Research Board, Number 362, 1971, pp. 10~19. A brief description of spectral and coherence analyses is provided, along with some practical examples of their use. The first application is an investigation of differences between an inexpensive replacement road-foDow~ng wheel and the standard wheel that comes with the profiIometer. The second example involves construction control and identification of differences between 2 methods for laying asphaltic base materials. Both of these investigations Involved statistically designed experiments so that more reliable conclusions could be obtained and confidence limits defineci. Slope variance and roughness index statistics were examined and compared with the spectral and coherence analyses results. Extension of these methods may provide the best approach yet available for development of adequate road profile specifications and construction condor. B-70

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Walker, R. S., "Profilograph Correlation with Present Serviceability Index - Asphalt Pavements. Final Report," Number DT-FH-7188-72-TX-24; Res. Rept. 579-1 F. Texas University- Arlington, Texas State Depl. of Highways & Public Transportation, 1989, 53p. A number of States are beginning to use roughness measurements from the California and Rainhart profilographs for construction control of rigid pavements. A recent Texas study, Research Study 8-10-87-56, provided correlations between Present Serviceability Index (PSI) as obtained from profile measured by the Surface Dynamics Profilometer (SD), and profile index (Pl) obtained between these profiIographs for rigid pavements. The PI was computed using the 0.! and 0.2 inch blanking bands, which are the ones most commonly used for computing Pl. This current report provides details on similar study which investigates correlations of PS} with Rainhart and California profiIograph PI measurements for asphalt pavements and concrete pavements with asphalt overlays. Two-tenths Ale sections in six different areas of Texas were measured with these devices for the study. Additionally, as in the first stucly, the 0.1 ant! 0.2 blanking bands were used to compute the Pl. In addition to the correlations with PST, correlations are also provicled between each profiIograph with one another. Walker, R. S., "Use of the Siometer for Profile Measurement. Research Report. Final Report," FHWA/TX-89-1203-IF;Res Rept 1203-1F, Texas University/FHWA, March 1991. This project was initiated to Investigate the profile measuring capability of the Siometer or "Walker self-calibrating process" so that it might be used for various profile measuring applications. Since the Siometer is capable of providing pavement profile estimates, it was desired to determine how closely these estimates were to actual profile, or to profile measurements made by the Surface Dynamics ProfiIometer (SDP) owned by the State. For the study, profile data from the Siometer was compared to that from the SDP for the same sections. From the results of the study the self-calibrahng process does a good job of measuring the longer profile wavelengths (about eight feet and greater). The shorter wavelengths are somewhat attenuated. The Siometer has been modified to implement the acceleration only, and South Dakota processes for measuring profiles anct rutting. The acoustic sensor provides better estimates of the shorter wavelengths which could also make the unit more suitable for profile measurements. Walker, R. S. and H-T Lin, "Profilograph Correlation Study with Present Serviceability Index (PSI). Demonstration Project No. 72. Automated Pavement Data Collection. Final Report.," Number FHWA-DP-~072-002; Res. Rept. 569-lF, Texas University-Arlington, Texas State Department of Highways & Public Transportation, 1988, 71p. The report provides correlations between Present Serviceability Index (PSI), as obtained from the Surface Dynamics Profilometer (SDP), and Profile Index (Pl) from He Califor~ua and Rainhart ProfiIographs. Two tenths mile sections in three areas of Texas new and old rigid pavements were measured with these devices for the study. In acidition to the correlations with PSI, correlations are also provicled between roughness data from the Walker Roughness Device (WRD). A mathematical mode! of the two profilographs is provided and the measuring capability of He two profilographs to various road profile frequencies or wavelength components is illustratecI. Power Spectral estimates of the road profile for the various PST classes are also presented. B-71

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Walker, R. S. and H-T Lin, "Profilograph Correlation Study with Present Serviceability Index," Transportation Research Record, Number 1196, Transportation Research Board, 1988, pp. 257-275. Several states are beginning to use roughness measurements from the Rainhart and California profiIographs for construction control of rigid pavements. Texas is also considering using the profiIograph for such purposes. However, the relationship between the roughness measurements provided by these devices and Present Serviceability Index (PSI), as obtained from the Surface Dynar~ucs Profilometer (SDP), is unknown. Since the Initial PSI of pavements is currently used in estimating the life of a pavement, the relationship between measurements from the profilograph and PST is needed. The other two roughness measuring devices used by the state, He Walker Self-Calibrating Roughness Device (WRD) and the Mays Ride Meter (MRM), have been correlated to PSI. A common measure of roughness, the PSI, is needed for all roughness measuring units to maintain consistent measurements. The paper provides correlations between PSI, as obtained from the SDP, and Profile Index (PI) from the California and Rainhart Profilographs. In addition to the correlations with PSI, correlations are also provided between each profilograph with one another and between roughness data from the WRD. A mathematical model of the two profilographs is provided, and the measuring capabilities of the two profilographs to various road profile frequencies or wavelength components are illustrated. Walker, R. S. and [. T. Phung, "The Walker Roughness Device for Roughness Measurements. Final Report," FHWAJTX-87/75+479-IF;Res Rept 479-IF, Texas University/Vrexas Dept. of Hwys./FHWA, July 1987. A Self-Calibradng Road Roughness Device known as the Walker Roughness Device (WRD) or Siometer has been under study and evaluation by the Department for the last several years. This crevice looks promising as a too! to collect road roughness for He Pavement Evaluation System. There is a very definite need for an automated data collection system for road roughness to eliminate some of the cost for this operation. This project was Initiated to upgrade the WRD and develop procedures so it can be used for collecting serviceability index roughness measurements for the state. This report describes the procedures for correlating the WRD with He SDP and using the WRD for roughness measurements. v Walker, R. S. and R. Beck, "Field Implementation of Non-Contact Profiling and Road Roughness Equipment. Final Report," Number FHWA/TX-88+394-lF;Res Rept 394-1F, Texas University/FHWA, August 1988. The Surface Dynamics ProfiIometer, which has been used for several years by the Texas State Department of Highways and Public Transportation for road profile and roughness measurements, was recently updated to include non-contact or laser probes In place of the road following wheels. The upgrade also included a more up-to-date on-board computing capability. Likewise, procedures and enhancements to the Walker Roughness Device (WRD, or Siometer) was also recently completed. This current project was initiated to monitor the usage of this equipment, making any necessary improvements, etc., as the equipment was being used in actual field use. The report provides results of various applications of this equipment during the past year. The data were taken primarily by D-IO personnel. B-72

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Walker, R. S. and W. R. Hudson, "Use of Profile Wave Amplitude Estimates for Pavement Serviceability Measures," Highway Research Record, Highway Research Board, Number 471, 1973, pp. 110-117. For a number of years, engineers were interested in developing objective criteria for designing and maintaining highways on the basis of pavement performance, i.e., riding quality. The development of the serviceability performance concept by Carey and Trick provided a methoct for developing such criteria. Although this method may seem rather crude to some, it is still the best methoc] available of those that consider the subjective riding-quality measurements of highway users. Several classes of instruments have been used for obtaining the objective measurements required for this concept; one that is the sIope-variance measuring device. Serviceability index models were developed based on slope variance of road profile ciata obtained with the surface dynamics profiIometer. Subsequently, a serviceability index model was cleveloped based on profile wave amplitude estimates of the road profile clata. This latter mode} has been found to be superior to the slope variance mode} and has now been used extensively for providing measurements in Texas. This paper describes this mode! and some of the results of its uses In field operations. Wambold, }. C. and [. E. DeFrain, "State of the Art of Measurement and Analysis of Road Roughness," Transportation Research Record, Number 836, Transportation Research Board, 1981, pp. 21-29. This paper is a review of the state of the art of the measurement and analysis techniques used to evaluate road roughness. A summary of some European work is included in this review; however, the emphasis of this paper is on work done in the United States. Road roughness is defined as the deviations of a pavement surface from a true planar surface with characteristic dimensions that affect vehicle dynamics, ride quality, dynamic pavement loads, and pavement clra~nage. Road roughness is measured by two general types of equipment: profiIometers, which measure these characteristic dimensions directly, and response-type equipment, which measure surface roughness as a dynamic response of the measuring equipment to that roughness. This paper discusses (a) the characteristic of road roughness, operating characteristics, and output of each Ape of roughness measuring equipment and (by the various methods of analysis and their application to highway safety, ride comfort, dynamic pavement loading, and pavement serviceability. These methods of analysis have been categorized into two general groups: those that provide a single number of index such as root mean square, slope variance, or present serviceability index and those Mat statistically provide more detail than a single index, such as harmonic analysis or power spectral density. Finally, a summary of present research projects on new equipment and analysis methods is given. Woodstrom, I. H., "Measurements, Specifications, and Achievement of Smoothness for Pavement Construction," NCHRP Synthesis of Highway Practice, Number I, Transportation Research Board, November 1990, 40p. This synthesis wiD be of interest to construction engineers, pavement designers, contractors, and others Interested in construction of new highway pavements with smooth surfaces. Information is provided on the various devices and specifications Hat are being used to obtain smooth pavements. The public rates a pavement primarily on its smooth-riding characteristics and highway agencies recognize that constructing smooth pavements results in fewer problems later B-73

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and lower annual maintenance costs. This report of the Transportation Research Board describes the devices and specifications highway agencies use to ensure that newly constructed pavements will provide a smooth ride. Woodstrom, I. H., "The California Profilograph," ASTM Symposium on Measurement, Control, and Correction of Pavement Roughness in Construction, Phoenix, Arizona, December 8, 1982. This paper focuses on the California ProfiIograph. The equipment which is a rolling straight edge type of Profilograph and has been used by California for 25 years for evaluating and controlling pavement smoothness. Current use of the equipment In evaluating pavement profiles in accordance with Test Method No. California 526 is discussed. The determination of profile index used in the evaluation processes is discussed. Typical trigger values of profile index that may warrant correcting profile defects together with the type of repair technique are presented. The use and development of other profiIographs in California since the late 1920s is mentioned. Also mentioned in this paper are typical ProfiIograph information collected using some earlier profilograph models. Woodstrom, J. H., 'rThe California Profilograph," Transportation Research Board, 1988. After experimentation with a lO-foot model, California developed a 25-foot rolling straightedge profilograph In the early 1950's. This was followed by the development of a test procedure and specifications which became standards by 1960. These standards and the profilograph equipment, with only minor changes, have been successfully applied to approximately 15,000 lane miles of concrete pavement construction in California since that time. Yoder, E. J., "Pavement Evaluation Using Road Meters," Number ^133, Highway Research Board, 1973. This workshop brought together engineers and researchers from the United States and Canada to discuss the development and uses of the road meter. The meeting was divicled into 5 distinct phases: 2. 3. 4. 5. Concepts ant! development of the road meter; Evaluation of the road meter; Correlation of road meter data with information obtained from other instruments. Road meter correlation with rating panels and effects of variables; and Use of the road meter for mass inventories and maintenance studies. In addition to the formal sessions, a I/2-day session was devoted to field inspection of several meters. During the field inspection, the participants were permitted to observe operation of the meters and to ask questions pertinent to their performance. It is difficult to summarize in several paragraphs the results of a comprehensive extension such as this, but several points were brought up from time to time by the participants that suggest needed areas of research. It was agrees! by all attendees that the road meter offers a quick and easy too! for obtaining a large number of measurements in a short period of time. It was brought out that its greatest usefulness is probably in mass inventories and in maintenance and priorities planning. \ B-74

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The ctiscussions at several points brought out the need for establishing some type of standards against which road meters of various makes can be calibrated. Perhaps this standard can take the form of a specially instrumented car or a standard pavement section at some central locale to which the various meters could be brought for comparative purposes. Another point that came up on several occasions was the manner In which correlations between road meter data and serviceability ratings can be made. Some individuals correlate road meter data with information from the CHLOE, roughometer, or some other instrument, and they then rely on established serviceability equations previously set up for these instruments. Other individuals establish their own equations by correlating road meter data with information obtained from rating panels. This latter method is the preferred method. Throughout the meeting a great deal of discussion was centered on the accuracy of data obtained by the roac3 meter. It was recognized that the shock absorbers on the car, the type of vehicle, the temperature, and many other factors have their effect on the data obtained from the instrument. However, great advances have been made in eliminating much of the variance caused by these factors. The null-seeking device recently cleveloped is a major step In this direction. The null device accounts for shifting of the readings as the test car progresses down the road. This and other refinements in the instrument have increased its accuracy greatly. There is little question that additional research should be conducted on this method of measuring pavement condition. Nevertheless, it is apparent that a great deal of information is already on hand and that the device can be put into routine use by highway departments In all parts of the world. Zhu, I. J. and R. Nayar, "APPARE: A PC Software Package for Automated Pavement Profile Analysis and Roughness Evaluation," Number 930963, Transportation Research Board, 1993. ProfiIographs are widely used instrument for characterization, specification and quality contra! Of initial pavement roughness during highway construction. Pavement roughness is usually evaluated manually from the profilograms, which are strip charts of profile traces, using a Blanlcing Band Profile Index (BBPI) algorithm to derive a Profile Index (PI). Consensus appears to be that the manual BBPI algorithm is laborious, subjective, and prone to operator errors. Consequently, the results are highly unreliable and unrepeatable. It appears that to date the BBPI algorithm has not yet been satisfactorily automated. Moreover, it is well-known that the PI correlates poorly with other widely used roughness indexes, such as the International Roughness Index (IRI). In this paper we report a new PC software APPARE currently being developed at the Louisiana State University for Automated Pavement Profile Analysis and Roughness Evaluation (APPARE) using the profilogram and other types of digitized pavement profile data. APPARE has an interactive graphical user interface and an image processing engine capable of digitizing profilograms using commercially available, low cost desktop scanners, and evaluate the PI and other widely used roughness indexes such as IRT using digitized pavement profile data from any profiling and roughness measuring instrument. In particular, a fine tuned computer BBP! algorithm and a new statistical algorithm are developed and successfully implemented. In addition, the evaluation of a newly proposed statistical roughness index is implemented for mathematical correlation between the various commonly used roughness indexes. Future development of this software is also discussed. B-75

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on the funciamental of roughness characterization that guided the selection of the standard road roughness index. Sayers, M. W. and T. D. Gillespie, "The International Road Roughness Experiment. Establishing Correlation and a Calibration Standard for Measurements," Number HS-039-586, International Bank for Reconstruction & Development, 1986. The International Road Roughness Experiment (IRRE) covered two categories of instruments, profiIometers and response type road roughness measuring systems (RTRRMs). The analyses demonstrated a good correlation between the RTRRMs and between the RTRMMs and profilometer records, and showed that they could ah be calibrated to a single roughness scale without compromising their accuracy. Thus, all the instruments tested will give outputs which are sufficiently accurate and reproducible for comparative evaluation, but will need to be correlated to some given standard to ensure transferability and consistency over time. A large array of standard Indices were evaluated, some based purely on Me geometric characteristics of the road profile, some based on simulation of the road profile - vehicle interaction, and some based on spectral analysis of the roughness recorder output. These analyses, which also Include measurement traversing speed are described in the text, and elaborated in the Appendices. Scofield, L. A., "Profilograph Limitations, Correlations, and Calibration Criteria for Effective Performance-Based Specifications," NCHRP Project 20-7, Task 53. The purpose of this study was to assess the state-of-~e-practice In the use of profiIographs for measurement of pavement smoothness. The critical objectives were to evaluate the nature and extent of problems and to recommend research to accomplish solutions to these problems. The study conducted a survey of Me states and industry to identify problems and to determine the state-of-the-practice. A literature search was performed and a limited analysis of the automated profiIograph filters conducted. The results of this study depict the state-of-the- practice through 1992. The California style profilograph has been successfully used for over one half a century to measure pavement profiles. It has been the principal Instrument used in the acceptance of concrete pavement ride qualities. During the 19SOs, the profiIograph was automated by computerizing the data collection and trace reduction and analysis. This created concern in the industry regarding the appropriateness of the results produced by the newer version. At this same time there was increasing interest in development and use of ~ncentive-disincentive specifications which placed higher emphasis on measurement accuracy. The results of the state surveys Indicated that 90/O of the respondents believe that smoother pavements reduce life-cycle costs and that smoothness requirements will Increase in the future. Currently, the majority of the states use the profiIograph for acceptance of pavement smoothness. Approximately 25% of the profiIographs In use by the states are computerized. The five highest ranked problems cletermined by the state survey ~nclucle, from highest to lowest; comparing profilographs to other roughness measurement devices, trace reduction repeatability, effect of short wavelengths on profile index, interpretations of profiIograph traces, and production rate of testing. B-62