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| 1.1. | Report of the Strategic Transportation Research Study. | |
| 1.2. | The 1986 Strategic Highway Research Program Research Plans. | |
| 2.1. | The four LTPP regions and current regional offices. | |
| 2.2. | Structure of the LTPP organization during the SHRP-LTPP years (1987–92). | |
| 2.3. | SHRP-LTPP and FHWA-LTPP staff members during the LTPP program transition. | |
| 2.4. | LTPP within the FHWA Turner-Fairbank Highway Research Center organizational structure (2012). | |
| 2.5. | General structure of the LTPP organization during the FHWA-LTPP years (1992–present). | |
| 2.6. | LTPP Committee meeting held in Washington, DC, on October 29, 2013. | |
| 2.7. | Connecticut Department of Transportation (CT DOT) staff meet with the LTPP program and regional support contractor staff. | |
| 2.8. | LTPP program staff and core contractors meet to discuss the status of different program activities. | |
| 3.1. | Memorandum of Understanding for the recruitment of LTPP SPS test sections. | |
| 3.2. | Reports of the winning papers from the 2001–2002 and 2003–2004 international data analysis contests. | |
| 4.1. | LTPP funding in fiscal years 1987–2014. | |
| 5.1. | Example of the research matrices used to plan the General Pavement Study experiments. | |
| 5.2. | Designated layout for GPS test sites. | |
| 5.3. | Sampling template and cell identification numbers for GPS-1 (Asphalt Concrete on Granular Base). | |
| 5.4. | Example of the research design matrices created for the Specific Pavement Study experiments. | |
| 5.5. | Test section layout for SPS-1 and SPS-2 projects (Strategic Studies of Structural Factors for Flexible and Rigid Pavements, respectively). | |
| 5.6. | Locations of the 2,509 pavement test sections across the United States, Puerto Rico, and Canada. | |
| 6.1. | LTPP data collection categories. | |
| 6.2. | Complete automated weather station installation with protective fencing. | |
| 6.3. | Prototype automated weather station used by the LTPP regional support contractors for in-house training of staff and to calibrate equipment components. | |
| 6.4. | A virtual weather station (VWS). | |
| 6.5. | Van-towed falling weight deflectometer equipment used in the LTPP program. | |
| 6.6. | Falling weight deflectometer equipment at the first LTPP “thump-off.” | |
| 6.7. | The cover of the FWD maintenance manual, used to keep the units operating at peak performance. | |
| 6.8. | An FWD being calibrated at the PennDOT regional calibration center early in the LTPP program. | |
| 6.9. | Mobile equipment used to photograph pavement distress. | |
| 6.10. | Sample of a computer-generated distress map from PADIAS 4.2 software. | |
| 6.11. | Film Motion Analyzer. | |
| 6.12. | Example of the multipage forms used to record distresses observed during LTPP manual distress surveys. | |
| 6.13. | Participants in a field review of distresses at an LTPP distress accreditation workshop. | |
| 6.14. | Screen shot from DiVA software showing a time-series chart of a pavement distress along with the table for all distresses for a test section. | |
| 6.15. | Edge drain inspection using videography. | |
| 6.16. | Locked-wheel skid tester currently in use for collecting friction data. | |
| 6.17. | The first (DNC 690) Profilometers used in the LTPP program. | |
| 6.18. | The T6600 Profilometer, in use from 1996 to 2002. | |
| 6.19. | ICC Profiler MDR 4086L3 (Ford E350 van), in use from 2002 to 2013. | |
| 6.20. | Ames Profiler in Ford E150 van, acquired in 2013. | |
| 6.21. | Manual Face® Dipstick® used to collect profile data in the LTPP program. | |
| 6.22. | Profile coordinators with four ICC profilers and the last K. J. Law Profilometer, gathered for a rodeo at MnROAD in 2007. | |
| 6.23. | Profile coordinators gather in College Station, TX, in 2013 to receive training from the LTPP program on the new Ames profiler units. | |
| 6.24. | Measuring rut depth with the 4-ft straightedge. | |
| 6.25. | Diagrams of the PASCO/CGH ROADRECON-75 showing (a) the transverse surface profiler system mounted in a vehicle; and (b) the geometric relations between the system’s optical bar and camera. | |
| 6.26. | Translating photographs produced by the automatic profilers into digital format. | |
| 6.27. | Normalization of transverse profiler measurements to lane edges. | |
| 6.28. | Three Face® Dipstick® profile measuring devices with carrying cases. | |
| 6.29. | A sample data transmittal form used by the highway agency to submit historical traffic data to the LTPP regional support contractor. | |
| 6.30. | A sample data transmittal form used by the highway agency to submit traffic estimates to the LTPP regional support contractor. | |
| 7.1. | Distribution of instrumented sites in the LTPP Seasonal Monitoring Program. | |
| 7.2. | A piezometer monitoring well and cap, used to determine ground water levels. | |
| 7.3. | Mobile monitoring equipment for downloading data collected at seasonal monitoring sites. | |
| 7.4. | The moisture probe designed at the FHWA highway research center. | |
| 7.5. | Schematic of the moisture probe that was used to obtain moisture content in unbound base and subgrade materials in the SMP, designed at the FHWA highway research center. | |
| 7.6. | SMP Phase II seasonal monitoring equipment installation at the Lake Ontario State Parkway site on SR 947A in western New York. | |
| 7.7. | Traffic ETG members who provided technical guidance and direction to the traffic pooled-fund study. | |
| 7.8. | Participating States in the LTPP SPS Traffic Data Collection Pooled-Fund Study. | |
| 7.9. | Load cell WIM installation. | |
| 7.10. | Staggered bending plate WIM sensors installed in concrete pavement. | |
| 7.11. | Installation of quartz piezoelectric WIM sensor spanning a full lane. | |
| 7.12. | Screen shot from LTPP Traffic Analysis Software showing loadings of Class 9 traffic. | |
| 7.13. | LTPP regional support contractor staff use the dynamic core penetrometer to determine the strength and density of the subgrade at the SPS site in Minnesota. | |
| 7.14. | Workers prepare a trench for forensic investigation of an SPS-5 site in Arizona. | |
| 8.1. | The LTPP Information Management System. | |
| 8.2. | Overview of the initial SHRP-LTPP database process, data flow, and releases circa 1989 to 1994. | |
| 8.3. | Functional diagram of LTPP data processing flow circa 1995 to 1999. | |
| 8.4. | Functional diagram of LTPP data processing flow circa 2000 to 2011. | |
| 8.5. | Functional diagram of LTPP data processing flow circa 2011 to present. | |
| 8.6. | DEC MicroVAX 3900 computer running the UNIX® operating system, used as the first LTPP National Information Management System (NIMS) server from 1989 to 1993. | |
| 8.7. | The LTPP DEC Alpha 3000 AXP 400 S computer system running the UNIX® operating system, used for NIMs server functions from 1993 to 1997. | |
| 8.8. | Compaq® ProLiant 1500 server running Windows® NT 16-bit operating system, used for the central database server 1997 to 2001. | |
| 8.9. | Dell™ PowerEdge™ 2900III installed in May 2009 at FHWA’s Turner-Fairbank Highway Research Center to serve as the secure central repository for LTPP electronic data into the future. | |
| 8.10. | Historical changes in the number of FWD data sets contained in LTPP data releases. | |
| 8.11. | Growth in number of FWD basin and load transfer measurements contained in the LTPP database since 2002. | |
| 8.12. | Growth in number of longitudinal pavement profile measurements. | |
| 8.13. | History of LTPP pavement surface distress surveys. | |
| 8.14. | Increase in transverse profile measurements since 1996. | |
| 8.15. | Growth in number of hourly climate data measurements collected by the LTPP program as part of the Seasonal Monitoring Program and automated weather station data collection efforts. | |
| 8.16. | Increase in total number of records in the materials test module starting in 1996. | |
| 8.17. | Growth in materials data for resilient modulus (Mr), creep compliance, and indirect tensile strength (IDT) using the P07 version 2 test protocol. | |
| 8.18. | Home page of the LTPP InfoPave™ Web site. | |
| 8.19. | LTPP InfoPave’s interactive map feature, showing the locations of LTPP test sections. | |
| 9.1. | Data collection guidelines published as manuals for falling weight deflectometer measurements, distress identification, and profile measurements and processing. | |
| 9.2. | Distress raters evaluate a pavement surface in an LTPP accreditation workshop. | |
| 9.3. | Profiler rodeo held at the Minnesota Road Research Project (MnROAD) site in Albertville. | |
| 9.4. | ProQual software, used to evaluate the acceptability of profile data. | |
| 9.5. | The Traffic Monitoring Guide. | |
| 9.6. | A distress-versus-time graph produced by the DiVA software. | |
| 9.7. | LTPP Data Analysis/Operations Feedback Report, used to provide feedback to the program regarding data that require investigation or correction. | |
| 10.1. | Introduction to the original LTPP Strategic Plan for Long-Term Pavement Performance Data Analysis, page 1, as adopted in 1999. | |
| 10.2. | Graphical compilation of the 1999 LTPP Strategic Plan for Long-Term Pavement Performance Data Analysis, its strategic objectives and product priorities. | |
| 10.3. | Illustration of the expanded strategic plan for LTPP data analysis, showing the extent and complexity of the plan as it has evolved since 1999. | |
| 10.4. | Excerpt of the expanded strategic plan for LTPP data analysis, showing analysis outcomes, supporting projects, and problem statements for Strategic Objective 1: Traffic Characterization and Prediction. | |
| 10.5. | Excerpt of the expanded strategic plan for LTPP data analysis, showing analysis outcomes, supporting projects, and problem statements for Strategic Objective 6: Maintenance and Rehabilitation Strategy Selection and Performance Prediction. | |
| 10.6. | MnROAD low-volume road and mainline test roadways owned and operated by the Minnesota Department of Transportation. | |
| 10.7. | Daniel Franta, a graduate student at the University of Minnesota, receives the 2012 ASCE-LTPP Data Analysis Contest Winner award. | |
| 10.8. | LTPP Product table from the 2001 LTPP Product Plan showing how existing and planned LTPP products address national pavement needs. | |
| 10.9. | LTPP Dynamic Modulus Prediction software, available from the LTPP program. | |
| 10.10. | Distress Identification Guide, Asphalt Concrete Pavements. | |
| 10.11. | Participating States in the LTPP SPS Traffic Data Collection Pooled-Fund Study. | |
