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1 ODOT Research Executive Summary Report Ohio Department of Transportation Office of Statewide Planning & Research Research Section 1980 West Broad Street, Mail Stop 3280 Columbus, OH PCR Evaluation FHWA Report Number: FHWA/OH-2013/8 Report Publication Date: July 2013 ODOT Project Duration: 15 months Start Date: April 13, 2012 Completion Date: July 15, 2013 Total Project Funding: $325, Research Agency: Applied Research Associates, Inc. Researchers: William Vavrik, Lynn Evans, Shad Sargand, Joe Stefanski ODOT Technical Liaisons: Aric Morse, Adam Au, Patrick Bierl, Rich Jones, Roger Green For copies of this final report visit PROJECT BACKGROUND The Ohio Department of Transportation (ODOT) is assessing the potential benefits and limitations associated with transitioning from a manual windshield-based pavement condition rating (PCR) to a more automated state-of-the practice process of collecting pavement condition data. Since 1985, ODOT technicians have traversed the State identifying pavement distresses, severities, and extents for use in pavement performance modeling, repair, and maintenance strategy selection, as well as planning and budgeting. As a result, the quality of these distress ratings and the Pavement Condition Rating (PCR) derived from ODOT raters serves a critical role in ODOT s pavement management activities. Therefore, ODOT is concerned that such a transition may reduce the completeness, accuracy, and continuity of their pavement distress data, which would render established models, predictions, and planning tools inaccurate, at least, or possibly unusable. This research was conducted to investigate that concern.

2 Ohio DOT Research Executive Summary Page 2 of 5 Several factors including safety, efficiency, workforce reductions, and changing reporting requirements provide impetus for considering a transition to more automated methods of collection and processing. A primary concern is the safety of ODOT raters. Although no accidents have been reported to date, increases in traffic on ODOT roadways, expanded roadway urbanization, and the potential for rater distraction and fatigue underscore the need to engineer increased safety through a more automated data collection process. Automated pavement distress data collection systems collect data at highway speeds, thus allowing the operator to concentrate on driving rather than driving and assessing the pavement condition at the same time. Also, automated systems eliminate the current need for raters to slowly drive the shoulder or stop alongside the road, resulting in increased rater safety. Finally, new reporting requirements of the Highway Pavement Management System (HPMS), including percent cracking and rutting, as well as the accountability requirements anticipated from the MAP-21 legislation (Moving Ahead for Progress in the 21 st Century), demand a level of distress reporting not easily attained using manual methods. STUDY OBJECTIVES The practical objective of this research is to evaluate the capabilities of current automated collection and semi-automated processing of ODOT pavement distress and PCR data. This investigation focused on determining if the state-of-the-practice collection systems and distress rating methods are a suitable replacement for ODOT s current manual approach. Thus, the three major objectives of this applied research project can be summarized as: 1. Identify the quality of vendor-collected data and its consistency with current ODOT PCR practices and results. 2. Determine the relative monetary, productivity, benefits, limitations, staffing requirements, and additional activities associated with each option. 3. Develop recommendations for implementing automated PCR data collection and processing that meets ODOT s needs, should ODOT choose to pursue this transition. DESCRIPTION OF WORK Three vendors collected digital 3-dimensional (3D) pavement images from 44 test sites representative of a range of pavement types and distresses common to ODOT roadways. Using manual, semi-automated, and automated approaches, they provided the distress, severity, and extent ratings for each site, following ODOT s PCR System Manual. Additionally, two experienced ODOT technicians individually rated the sites before and after vendor collection. The results provided comparisons of the vendors abilities to accurately match more than 350 ODOT distress, severity, and extent rating occurrences. To identify means to further improve correlations, ODOT raters conducted detailed interviews and image reviews with vendors. Surveys of six vendors and 18 State agencies revealed the unique properties and capabilities of vendor systems, productivity rates, costs, and approaches to ensuring high data quality. An

3 Ohio DOT Research Executive Summary Page 3 of 5 implementation plan was designed, effects of implementation were evaluated, and supporting information was prepared for developing equipment and services requests for proposals. RESEARCH FINDINGS AND CONCLUSIONS The data quality, cost, productivity, benefits, and requirements review indicate the potential for a successful transition from manual to state-of-the-practice automated data collection and semi-automated analysis of pavement distress data. However, because vendors have not demonstrated the ability to match the presence, severity, and extent of all 44 of ODOT s pavement condition rating distresses, several additional activities will be necessary to implement this system. These activities include working with a vendor to optimize the ability to mirror the PCR; changes to the PCR where the vendor cannot identify the distress, severity, or extent; changes to the pavement performance prediction equations; and changes to the pavement management system (PMS) decision trees. Participating vendors (Fugro-Roadware Inc.; Mandli Communications, Inc.; and Pathway Services, Inc.) were only able to match ODOT distress, severity, and extent ratings in 14 percent of the noted occurrences. Nevertheless, they achieved an average of 35 percent match of ODOT distress and severity ratings and displayed the ability to recognize the presence of nearly 75 percent of distresses identified by ODOT raters. No vendor stood out as providing optimal results. Subsequent detailed reviews of images and interviews with vendors revealed the causes and resolutions for a majority of these discrepancies. If these resolutions are implemented, and final field calibration of a selected vendor s ratings is conducted, it is anticipated that a high correlation will be achieved for 16 of the 44 distresses, with their severities and extents. No significant change to the ODOT reporting methods and data continuity of these distresses is anticipated. After final field calibration, vendors are expected to match the ODOT distress, severity, and extent ratings for 14 pavement distresses at only a moderate level (50 to 75 percent). This limitation suggests that reporting requirements of these distresses will need to be modified. These modifications should provide representative data for each distress but will report that data within the abilities of the technology and the semi-automated distress identification systems. For eight or nine distresses, calibrated vendor ratings are not expected to match ODOT ratings at a moderate or high level. These distresses include pumping, pressure damage, corner breaks, punchouts, and shattered slabs on asphalt concrete (AC) overlays of Portland cement concrete (PCC) pavements; pumping, low-severity surface deterioration and settlement on PCC pavements; and possible edge cracking on AC pavements. Transition to more automated data collection is expected to require that most or all of these distresses be revised, removed, or replaced in the ODOT distress manual. Vendor results could possibly be accepted at a lower quality level, but this would extend the transition time and increase data variability. These limitations will require additional ODOT efforts to adjust and calibrate the Pavement

4 Ohio DOT Research Executive Summary Page 4 of 5 Management System (PMS). The efforts to adjust the PCR and PMS systems will be in addition to the effort and cost to procure the new technology. Table 1 provides estimated equivalent uniform annual costs (EUAC) for several options available to ODOT for purchasing a system, collecting and evaluating the data in-house, or procuring vendor services. This table also includes the cost associated with ODOT s current distress collection procedures. To continue ODOT s annual review schedule, option 1 would require the employment and training of two additional technicians; one additional technician would be necessary for options 2 and 3. Vendors vary in estimated costs, and the estimates for options 1 through 4 include transitional training by the vendors. Vendors indicate their ability to complete option 4 in 28 weeks. Although automated system costs greatly exceed those of current ODOT manual data collection, these increased costs are partially offset by the benefits associated with increased rater safety, correlation with Federal reporting requirements, and the advantages of 3D technology. Table 1. Estimated EUAC of collection and processing options. Option Description EUAC 1 ODOT purchases system, collects, and processes data. $1,056,000 2 ODOT purchases system and collects data. Vendor processes data. $1,787,000 3 Vendor collects data. ODOT processes data. $1,472,000 4 Vendor collects and processes data. $2,135,000 5 ODOT collects and processes data according to current procedures. $386,000 Because ODOT currently operates pavement data collection equipment in the Technical Services group, a variation on option 1 or 2 could be implemented at a lower cost, leveraging the work across ODOT and realizing economies of scale. Additional ODOT efforts required for the transition include the estimated hours shown in Table 2. Of particular note are items 6 through 9. Because vendors are unable to adequately match ODOT distress, severity, and extent ratings for all distresses, ODOT will be required to modify the PMS decision trees from which decisions regarding the appropriate maintenance or rehabilitation and district budget needs are determined. Models to estimate the rate of change expected with each distress must also be updated for certain distresses, along with the methods employed for weighting distress, severities, and extents. The effect of missing distresses must also be accounted for in ODOT s revised PCR overall pavement performance index. Updates to ODOT s Deighton PMS software will also be required. To ensure continuity between the current PCR and PMS results and those ensuing from the modified set of reported distresses, it is suggested that dual collection using the current and revised system be conducted on the pavements from at least two districts for two to three years. That information will then be evaluated to develop correlations between manual and semi-automated distress data and resulting management processes.

5 Ohio DOT Research Executive Summary Page 5 of 5 Table 2. Estimated ODOT person hours associated with additional transition activities. Item Description ODOT hours 1 Vendor procurement 80 2 Vendor distress identification optimization Revisions to distress ratings and update of the Distress Manual Establishment of QC/QA program Maintenance of annual QC/QA program (annually) Modification of Pavement Management System decision trees Updates of PMS performance models 1,000 8 Dual collection of distress data by vendor and ODOT raters (annually) Development of correlations between manual and semi-automated 240 IMPLEMENTATION RECOMMENDATIONS If ODOT moves forward with transitioning from manual to semi-automated pavement distress data collection and processing, expected completion of all aspects of this transition will take approximately two to four years. The following implementation activities are recommended. 1. Select a vendor or vendors for further evaluation and implementation. 2. Optimize the vendors ability to match agency distress, severity, and extent ratings. 3. Reevaluate/reconsider the transitioning based on actual optimized results. 4. Adjust pavement distress reporting methods and distress index to account for limited vendor distress, severity, and extent identification. 5. Establish QC/QA program to ensure optimized data collection levels. 6. Implement staged or full-scale distress collection and processing systems and procedures. 7. Modify Pavement Management System decision trees and performance models. 8. Develop correlations between manual and semi-automated distresses, severities, extents, and indices to provide data continuity. The technology increases in automated data collection and analysis are accelerating, State DOTs are evaluating and implementing the new technology, and the FHWA is evaluating which automated performance measures can be expected in the future. ODOT has a solid PCR method, years of historic data, a mature PMS, and a culture of performance metrics. The path to implementing new technology will require careful consideration, pushing technology to meet ODOT s needs, and some changes to ODOT s current systems, including the use of a dual system for a few years. This project indicates that a transition to state-of-the practice technology is feasible. It also reveals that leveraging ODOT s extensive expertise and modern collection system capabilities can serve to establish ODOT with a top-notch pavement management system effectively poised to deal with ODOT s future needs.