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Pavement management SyStemS: Putting Data to Work Pavement management systems are recognized as important tools to help transportation agencies opti- mize the use of available funding, better communicate funding needs, and more objectively manage their pavement network. Pavement management systems are now required for managing the National Highway System under the Moving Ahead for Progress in the 21st Century (or MAP-21) and the Fixing Americaâs Surface Transportation (or FAST) acts. There are many examples of state departments of transportation (DOTs), local agencies, toll authorities, and other public agencies that have been using pavement management tools for decades. The maturity of these systems varies, as does the extent to which the data are integrated into the agencyâs decision processes. The objective of this synthesis study is to document current pavement management practices in state and provincial transportation agencies to determine the extent that pavement management data are being used to support agency decisions. The synthesis focuses on the use of pavement management analysis results for resource allocation, determining treatment cost-effectiveness, program develop- ment, and communication with stakeholders. The information contained in this synthesis was obtained using three sources. First, a litera- ture review was conducted to provide background information about the state of the practice and recent developments that have taken place in the use of pavement management data. Sec- ond, a web-based survey was distributed to pavement management engineers in each of the 52 state transportation agencies (including Puerto Rico and the District of Columbia) and the 10 Canadian provincial ministries of transportation (MOTs) asking for information on their current practices in pavement management. Forty state DOTs (80%) and eight provincial MOTs (80%) responded to the survey. The state totals presented in the synthesis also include a responses from Puerto Rico. Finally, representatives from five agencies were interviewed by telephone to obtain more specific information about innovative uses of pavement management data. The agencies that were selected to participate in these interviews were identified based on their responses to a survey question asking about innovative uses of their data. These case examples illustrate how pavement management data has been used to improve data quality, evaluate treatment effectiveness, expand the use of pavement management data within a DOT, improve agency performance measures, and establish performance measures for highway concession agreements. The literature search results indicate that there has been a significant progression in pavement management since its inception in the 1960s. Initially, pavement management data were used pri- marily to document pavement conditions and estimate funding needs. Today, there is evidence that pavement management data are also used to assess performance trends, calibrate design models, evaluate the cost-effectiveness of different treatment strategies, and recommend candidate projects for a preservation program. Because of the increased importance of pavement management to support current performance-based legislation at the federal level, state transportation agencies are required to have pavement management processes in place to determine budget needs and to evaluate the cost-effectiveness of alternate investment strategies. State transportation agencies are also required to have a Data Quality Management Program to ensure the reliability of the data used to report pave- ment condition metrics to FHWA. Summary
2 Pavement management continues to evolve as researchers and practitioners explore the appli- cability of using pavement data to address safety and environmental impacts, identify and assess risks, set performance targets, and monitor contractor performance under highway concession and long-term performance-based contracts. At a recent international pavement management conference, practitioners demonstrated sophisticated uses of pavement management data for multi-objective analysis, asset valuation, and integration with sustainability-rating tools. Conference participants also discussed the use of pavement management data in response to natural disasters; demonstrating the consideration of risk in agency investments and the importance of integrating pavement manage- ment with other agency data sources. Further insights into current pavement management practices were provided from the survey distributed to pavement management practitioners in state DOTs and Canadian MOTs. The results indicated that of the 49 agencies that responded to the survey, 49% of the state DOTs and 38% of the MOTs have customized, proprietary pavement management software in place. An equal number of agencies (16%) are using software that was developed in house or software that was provided by a vendor and modified in house. Five agencies (10%) reported that they have no formal pavement management software in place and four (8%) are using a vendor-supplied program that has been modified or is used in conjunction with other software programs. Inventory and condition information on the high-volume highway networks is available in all but one of the responding agencies (98%). There are fewer U.S. agencies that have inventory (93%) and condition information (90%) for the non-National Highway System state-maintained systems and a significant drop in the number of U.S. and Canadian agencies that have this information for front- age roads, shoulders, entrance and exit ramps, and high-occupancy vehicle lanes or bus lanes. For example, only 42% of the responding agencies indicated that they have a frontage road inventory and 27% that they have condition data for their frontage roads. According to the survey, pavement distress data are collected in both directions on divided highways by 90% of the responding agencies. Distress data are collected in both directions less often on nondivided highways; only 33% of the responding agencies noted that they collect data in this manner. Fifty-nine percent of the responding agencies collect distress data on nondivided highways in one lane and in one direction. In addition to pavement condition information, the most common data available in a pavement management database include (percentages based on 48 responses): â¢ Individual distress values (92%). â¢ Traffic data (90%). â¢ Composite indices (85%). â¢ Individual indices (83%). â¢ Treatment history (77%). â¢ Treatment costs (77%). Fewer agencies reported that their databases contain information on routine maintenance activi- ties (42%), remaining service life (31%), materials or construction data (23%), detailed performance data (13%), or drainage information (2%). The survey investigated the methods used to develop pavement deterioration models and treatment rules and explored the types of analyses that are conducted with the available data. The results indicated that of the 48 agencies that responded to this question, most (69%) develop customized models using agency data. Family models, which reflect pavement deterioration rates for pavements with similar characteristics, are used in 56% of the agencies. The responses indicated that 48% of the agencies model performance indices rather than individual distresses (38%). Five agencies (10%) reported that their system does not predict pavement performance and three (6%) that they use default models. The agen- cies that have developed customized models use variables such as pavement type (94%), pavement functional condition (75%), highway system (72%), treatment history (69%), and traffic data (63%). These models are updated by most agencies at least every 3 years (94%).
3 Questions explored various features of the pavement selection capabilities of pavement man- agement systems. Of the 48 responding agencies, there was not a lot of variation in the types of treatments recommended by the software. For instance, 33% agencies indicated that their pavement management system generates treatment categories, 29% provide specific treatment recommenda- tions, and 25% offer both. In the 46 agencies that responded to a question about pavement preser- vation treatments, nearly all (83%) indicated that their pavement management systems consider pavement preservation treatments in their analysis. Feasible treatment options are identified using variables such as pavement condition (96%), pavement type (87%), traffic volumes or loads (78%), pavement age (70%), highway system (63%), and last treatment (59%). According to the 46 agencies that responded to the question, the most common analysis capabili- ties provided by pavement management systems are: â¢ Forecast expected conditions under different funding scenarios (85%). â¢ Prioritize project recommendations under constrained funding (80%). â¢ Estimate funding required to achieve performance targets (80%). â¢ Contribute to the development of a transportation asset management plan (74%). â¢ Evaluate the cost-effectiveness of different treatments (74%). â¢ Set program budget allocations (72%). â¢ Allocate funding to regions based on needs (70%). â¢ Set performance targets for portions of the network (70%). â¢ Analyze gaps between current and desired performance (61%). â¢ Prepare Highway Performance Monitoring System submittals for FHWA (48%). However, there are only three types of analyses that have been performed by more than half of the 49 agencies that responded to the survey. These include the following traditional applications (percentages based on 42 total responses): â¢ Forecast expected conditions under different funding scenarios (83%). â¢ Estimate funding required to achieve performance targets (74%). â¢ Prioritize project recommendations under constrained funding (64%). Most agencies (77% of 47 total responses) reported that their pavement management recommen- dations match the projects in their improvement programs at least 40% of the time. Only four agen- cies (9%) noted that the match exists less than 40% of the time, indicating that political influences, local conditions, insufficient funds, and district independence impact the final project selection. Several questions were presented to learn more about the processes in place to keep the pave- ment management current, the documentation of these processes, and the degree to which pavement management is integrated with other programs. Forty-eight agencies responded to the question about existing processes. The results indicated that agencies have processes to update historical work activ- ities (81%), verify the quality of data collected (79%), update pavement surface type based on work activities (73%), and update the database with actual project costs (42%). Pavement management systems are most commonly integrated with an agencyâs geographic information system (44% of 48 responding agencies) and the centralized roadway database (27%). Twenty-nine percent of these agencies reported that their pavement management system operates independently. Pavement management models are documented in most agencies, with pavement condition survey procedures (81% based on 47 total responses), treatment rules (62%), and performance model equa- tions (57%) being most common. Thirty-six percent of agencies report having documented their quality assurance procedures and an equal percent have documented pavement roles and responsibilities. A number of different types of pavement management information are shared with stakeholder groups. Based on the 41 responses by U.S. agencies, the most common information shared with elected and appointed officials is information about current (68%) and forecasted (54%) pavement conditions, as well as future funding needs (51%). Agency decision makers in the United States
4 are provided with the same information, but also receive information on candidate projects (76%), funded projects (66%), and expected future funding levels (56%). There have been a number of different enhancements that have been made or will be made to pavement management systems in the next 2 years. Among the responses from 41 U.S. agencies, the two most common changes expected in the next 2 years relate to improving procedures for data qual- ity management (63%) and updating pavement management software (61%). Changes to pavement condition surveys have also been completed in recent years, with many agencies reporting that they have moved to continuous surveys rather than use a sampling approach (71%) and are now using automated data collection equipment (59%). Over the next 2 years, many agencies plan on analyzing investment needs across asset types (51%) and incorporating risk into investment decisions (37%). Several agencies indicated that they would like to collect pavement structural condition (six), pave- ment friction data (three), pavement material data (six), and improved cracking data using automated equipment (three) to improve their practices. Interviews were conducted with five agencies to explore innovations in the use of pavement man- agement information. At least two important findings can be extracted from the examples. First, the availability of reliable construction history records, a consistent location referencing system across databases, and dependable performance data were recognized as important contributors to the use of pavement management data to evaluate treatment effectiveness, prioritize investments based on cost-effectiveness, and monitor contractor performance under a publicâprivate partnership agree- ment. Second, collaboration across agency silos can be beneficial, as demonstrated by the Maryland DOTâs use of pavement management data to identify high-risk curve locations in a statewide effort to reduce the number of crashes in and around curves. The following research suggestions are provided as a means to improve the way pavement man- agement systems are used. â¢ The development of guidelines for analyzing risk, optimizing the use of available funding, setting performance targets, allocating budgets, and evaluating network-level structural condition to support the broader consideration of these factors in pavement management. Improved information on pavement structure and materials data to support their pavement management analyses would be helpful to pavement management practitioners. The survey responses indicated that data are largely available on the Interstate and National Highway Sys- tem, but less so on the remainder of the system. Network-level structural condition surveys and stronger links to construction and materials databases were identified by several respondents as desired data. In addition, the survey results noted that pavement management is largely being used to dem- onstrate the impacts on network conditions associated with different funding levels, esti- mate funding needed to achieve performance targets, and prioritize recommendations under constrained funding. However, fewer than 20 of the 41 state DOTs and only four of the seven Canadian MOTs that responded to the survey are using their pavement management systems for other types of analyses, including setting performance targets and evaluating the cost-effectiveness of investment spending, even though their software provides these capabili- ties. In terms of enhancements, 21 agencies expressed an interest in enhancing their ability to analyze investments across asset types over the next 2 years and 15 agencies expressed interest in incorporating risk into their investment decisions during that timeframe. â¢ The development of a framework for using pavement management data to support the whole-life costing analysis and other capabilities required for the development of a Trans- portation Asset Management Plan (TAMP). There are still several states that do not have pavement management software that will satisfy the minimum requirements outlined in the Notice of Proposed Rulemaking for developing a TAMP. The development of a framework for using pavement management data to support the development of a TAMP, including the conduct of a whole-life cost analysis, would allow agencies to use their pavement management data to better evaluate the long-term cost-effectiveness of different investment strategies and more fully support their agencyâs asset management efforts.
5 â¢ The development of electronic templates that practitioners could use to document pave- ment management treatment rules, performance models, roles, and responsibilities. A number of agencies document their pavement condition survey procedures, their treatment rules, and their performance models; however, there is less evidence that documentation exists for data quality procedures or pavement management roles and responsibilities. The absence of this type of documentation leaves an agency at risk if pavement management personnel retire or change positions. The development of electronic templates would simplify and standardize the documentation process for practitioners. â¢ The conduct of technology transfer and outreach activities that showcase best practices in pavement management and highlight the use of pavement management data for non- traditional uses. As noted earlier, pavement management systems are not being fully utilized at the present time. In addition, the results indicated that pavement management systems are not largely integrated with other management systems and databases, which could limit the feasibility of using pavement management data for nontraditional purposes. The conduct of technology transfer and outreach activities (such as training courses, web conferences, and peer exchanges) provides an opportunity for practitioners to learn about strategies for improving practices from their peers. â¢ The establishment of guidelines for mining pavement management data so it can be used in developing performance measures for warranty contracts and other types of publicâprivate partnerships. The results of the survey indicated that only two agencies are using pavement management data to develop performance measures for warranty contracts and other publicâ private partnerships. As this contracting method becomes more common in the United States, transportation agencies will benefit from the availability of guidance on using pavement man- agement data to establish effective performance measures to monitor contractor performance.