The Texas Department of Transportation has been experiencing budget fluctuations in the recent past. These budget fluctuations can have a pronounced effect in the agency’s highway maintenance operations if key maintenance activities must be delayed due to budget constraints. The methodology proposed in this research project aims at reducing the impact of budget fluctuations on highway maintenance by identifying and ranking maintenance activities based on a set of identified maintenance objectives. With the help of maintenance experts from the highway agency, four maintenance objectives were identified and considered for this research project: include Aesthetics, Safety, System Operations and System Preservation. A similar process was conducted to identify the most relevant maintenance activities from a list of over 120 different maintenance functions used by the Texas Department of Transportation. The original list of maintenance functions was reduced by combining similar sub-categories. Ultimately, 16 maintenance functions were identified and included in this research project, representing an average of over 75 percent of the agencies maintenance expenditures between fiscal years 2008 – 2010. These four maintenance objectives and sixteen maintenance functions were then evaluated by maintenance experts from different geographic locations of the state using the Analytical Hierarchy Process to produce an Overall Relative Weight for each maintenance function. This process allowed each evaluator’s judgments and preferences to influence the final weight values and rankings of the maintenance functions. The Overall Relative Weight corresponds to each maintenance sub-category’s component from each maintenance objective and can be defined as the performance risk of not carrying out the maintenance activity. This information can be used by maintenance engineers and administrators, when faced with budget shortfalls, to suspend or reduce maintenance activities that have a lower performance risk in favor of performing activities that have a higher one. This will dampen the impact of budget fluctuations on highway maintenance operations by performing critical maintenance treatments at the expense of less critical. / text

As is the case for most of the Departments of Transportation in the U.S., the Texas Department of Transportation has been experiencing fluctuations of budget for maintaining and preserving its highway infrastructure over the recent years. If the maintenance budget shortfall lasts for an extended period of time, the condition of the highway network would be harmed directly or indirectly since some maintenance work would be deferred or cancelled. Thus, in order to control and minimize the risk caused by maintenance budget reductions, it is important for highway agencies to adjust their maintenance and rehabilitation policies to accommodate budget fluctuations. This thesis presents a methodological framework that helps highway agencies quantify the risks to highway networks, and revise the highway routine maintenance work plans to minimize the impact of budget fluctuations. The proposed methodology aims to assist highway agencies in prioritizing and selecting maintenance functions according to the risk of not performing a specific maintenance activity. Also, this methodology considers the subjective nature of decision makers’ assessments, allowing different levels of confidence and different attitudes toward risk to be captured as the uncertainty and imprecision involved in the decision making process. In the case study, the proposed methodology is tested with a set of data obtained from the Texas Department of Transportation. The result is compared with the outcome obtained from the crisp Analytical Hierarchy Process using the same set of data. The outcomes from the two methodologies are very close, validating the effectiveness of prioritizing highway maintenance functions using Multi-Attribute Analysis with Fuzzy Pairwise Comparison. / text

The concept of involving the public in the development of transportation solutions was built in the Federal-Aid Highway Act of 1956, the legislation that authorized the construction of the Interstate Highway System. Better plans, transparent process, and public support are some of the benefits that road managers can obtain by educating and involving the general public. During the last two decades the volume of research performed related to the topic of customer-driven highway maintenance suggests an increasing level of interest in the field. Most research concentrates on gathering information from road users to assess the performance level of highways. However, public opinion can also be collected for measuring the quality of the service delivered by maintenance units. Assessing product and service delivery performance is important for determining the overall performance of highway maintenance programs. The present study examines the relationship between road users' overall perceptions of the quality of highway maintenance services and the variables that define the highway maintenance service quality domain. The results of the study indicate that two service dimensions, Safety and Reliability, explain about half of the variance in overall perceptions of highway maintenance service quality. The procedures developed for the study provide an initial step for further improvement of the highway maintenance service quality measurement. / Ph. D.

The transportation system is vital to the nation’s economic growth and stability, as it provides mobility for commuters while supporting the United States’ ability to compete in an increasingly competitive global economy. State Transportation Agencies across the country continue to face many challenges to repair and enhance highway infrastructure to meet the rapid increasing transportation needs. One of these challenges is maintaining an adequate and efficient agency staff. In order to effectively plan for future staffing levels, State Transportation Agencies need a method for forecasting long term staffing requirements. However, current methods in use cannot function without well-defined projects and therefore making long term forecasts is difficult. This dissertation seeks to develop a dynamic model which captures the feedback mechanisms within the system that determines highway staffing requirements. The system dynamics modeling methodology was used to build the forecasting model. The formal model was based on dynamic hypotheses derived from literature review and interviews with transportation experts. Both qualitative and quantitative data from literature, federal and state database were used to support the values and equations in the model. The model integrates State Transportation Agencies’ strategic plans, funding situations and workforce management strategies while determining future workforce requirements, and will hopefully fill the absence of long-term staffing level forecasting tools at State Transportation Agencies. By performing sensitivity simulations and statistical screening on possible drivers of the system behavior, the dynamic impacts of desired highway pavement performance level, availability of road fund and bridge fund on the required numbers of Engineers and Technicians throughout a 25-year simulation period were closely examined. Staffing strategies such as recruiting options (in-house vs. consultants) and hiring levels (entry level vs. senior level) were tested. Finally the model was calibrated using input data specific to Kentucky to simulate an expected retirement wave and search for solutions to address temporary staffing shortage.

Many highway maintenance agencies are facing an increased pressure to utilize their limited resources while still achieving the optimum winter highway maintenance outcome. Also there is a tendency to privatize maintenance operation, in order to improve the road user's satisfaction by bringing more competition to winter maintenance operations. Given this context the purpose of this research is to develop an effective performance measurement system that can evaluate how well agencies have conducted winter maintenance activities to meet the road user's expectations of safety and mobility. Though there have been performance measurement studies conducted in the winter maintenance area, few of them are comprehensive enough to evaluate winter maintenance outcomes, while at the same time taking storm severity, road system characteristics, and maintenance effort together into consideration. To address this deficiency, several particular challenges must be considered: first, how to evaluate the storm severity for individual storms; second, how to evaluate maintenance outcomes using a series of quantitative measures; and third, what are the appropriate targets that maintenance outcomes can be compared with, considering outcomes are sensitive to maintenance input, weather severity, road classifications, and traffic specifications. To address these questions: A storm severity index is developed; studies on effects of weather were quantitatively synthesized by meta-analysis; effects of weather and maintenance on road surface conditions are estimated by MLR; SEM (Structural Equation Modeling) is applied to estimate the direct and indirect effects of maintenance on mobility and Multiple Classification Analysis (MCA) was applied to estimate the contribution of winter maintenance to safety. The final result of this research is an applicable winter maintenance performance measurement system. It informs maintenance agencies where they excel at and where improvements are needed for the specified goals. Further, the developed road surface condition prediction model can be used as a predictive tool to allow agencies to conduct "what if" experiments that will lead to optimization of maintenance practice over time. The relative magnitudes of the effects of different maintenance methods on mobility and safety that is estimated by the models will enable agencies to assign priorities, and to compare maintenance outcomes based on the input resources.

The Texas Department of Transportation has been experiencing maintenance budget fluctuations recently. The shortage of budget has a negative impact on the agency’s maintenance strategies and results in the undesirable deterioration of highway conditions increasing the risk towards both road users and the agency. This paper aims at developing a methodology to minimize the impact of budget fluctuation by quantifying the risk of not performing a maintenance activity and identifying the priority of maintenance activities based on the quantified risk. With the help of maintenance experts from TxDOT, four maintenance objectives and 16 maintenance function groups were identified and a hierarchy structure was developed based on the objectives and function groups. Four pilot districts were selected to represent the different demographic and climatic regions in Texas and maintenance experts were selected from the four districts to participate in the workshop. The Overall Relative Weights of 16 maintenance function groups were determined based on the individual evaluator’s judgments using the Analytical Hierarchy Process. To determine if the four pilot districts give different relative importance to the four defined objectives and different priority to the 16 maintenance groups, statistical analyses were conducted with the four sets of values, one for each of the four pilot districts, using Kruskal-Wallis test. At last, a web-based prototype system was developed to assist users in generating the list of maintenance projects under budget constraints. Exposure factors, ADT and truck volume, were applied in the system to factor in the impact of traffic to the maintenance strategy. Users of this system can choose to use the weights and parameter values from one of the pilot districts which they think is most comparable to their own district or the state average values that has been proved to be applicable to all the districts in Texas. / text

Performance goals for a highway system are an indication of the desired system condition, and the level of service to be provided to its users. Setting the appropriate performance goals has a significant impact on the way highway agencies conduct business. With growing needs and limited resources, the consequences of setting different levels of performance goals should be examined and compared to optimize the highway infrastructure needs at the network level. Three interacting sets of costs are typically considered for a complete economic appraisal of highway projects: construction, maintenance and road use costs. Due to the shift in focus from design-and-build mode to the repair-and-maintain mode, this study focuses on maintenance related costs and the road user cost aspects only. Maintenance and rehabilitation activities on pavement infrastructure are ongoing processes that are required for the entire road network. This suggests that for long planning horizons and geographically extensive networks, their application usually results in significant financial needs. Typically, highway agencies have based their policy decisions such as the target condition levels for the system on the budget needs for maintenance and rehabilitation actions. Since in most cases, the funding needs exceed the available budget, the required preventive and routine maintenance activities suffer or are overlooked completely. Failure to timely apply these maintenance actions cause the pavements to deteriorate more rapidly into condition states that require for more expensive rehabilitation actions during the life cycle of the pavement. Over time, a vicious cycle is instigated in which the maintenance and rehabilitation needs of the network keep increasing each year. Although most highway administrators acknowledge the fact that pavement preservation is perhaps the most effective way of using the limited budgets available, the costs associated with deferring maintenance actions is oftentimes overlooked when establishing performance goals for the system. Road user costs in the form of costs for vehicle operation have been recognized as another large component of the total transportation related costs. These costs are then arguably the most important to consider for a complete economic appraisal. Ironically, they are also often disregarded while making important policy decisions. Other road user costs such as those related to the impact of traffic congestion and detours caused by construction and maintenance activities are difficult to quantify and were not accounted for in this study. Although it is widely accepted that establishing suitable performance goal is critical for system maintenance and preservation, a framework that considers the inter-relationship between conflicting objectives of minimum maintenance and rehabilitation costs, deferred maintenance costs, and vehicle operating costs to the users does not exist. This thesis proposes a methodological framework that is aimed at assisting highway agencies with the problem of objectively analyzing policy decisions in terms of the performance goals for their highway networks that would minimize the total transport costs to the society. In a case study of the proposed framework, the highway network managed by the Texas Department of Transportation was examined for different performance goals. The results from the case study indicate that setting lower performance goals lead to savings in the M&R needs, but at the same time, they also significantly increase the exogenous costs such as deferred maintenance costs and the vehicle operating costs. / text

Highly deteriorated U.S. road infrastructure, major budgetary restrictions and the significant growth in traffic have led to an emerging need for improving efficiency and effectiveness of highway maintenance practices that preserve the road infrastructure so as to better support society's needs. Effectiveness and efficiency are relative terms in which the performance of a production unit or decision making unit (DMU) is compared with a benchmark (best practice). Constructing the benchmark requires making a choice between an "estimation approach" based on observed best practices (i.e., using data from input and output variables corresponding to observed production units (DMUs) to estimate the benchmark with no elaboration on the details of the production process inside the black box) or an "engineering approach" to find the superior blueprint (i.e., focusing on the transformation process inside the black box for a better understanding of the sources of inefficiencies). This research discusses: (i) the application of the estimation approach (non-parametric approach) for evaluating and comparing the performance of different highway maintenance contracting strategies (performance-based contracting versus traditional contracting) and proposes a five-stage meta-frontier and bootstrapping analytical approach to account for the heterogeneity in the DMUs, the resulting bias in the estimated efficiency scores, and the effect of uncontrollable variables; (ii) the application of the engineering approach by developing a dynamic micro-level simulation model for the highway deterioration and renewal processes and its coupling with calibration and optimization to find optimum maintenance policies that can be used as a benchmark for evaluating performance of road authorities. This research also recognizes and discusses the fact that utilization of the maintenance budget and treatments that are performed in a road section in a specific year directly affect the road condition and required maintenance operations in consecutive years. Given this dynamic nature of highway maintenance operations, any "static" efficiency measurement framework that ignores the inter-temporal effects of inputs and managerial decisions in future streams of outputs (i.e., future road conditions) is likely to be inaccurate. This research discusses the importance of developing a dynamic performance measurement framework that takes into account the time interdependence between the input utilization and output realization of a road authority in consecutive periods. Finally, this research provides an overview of the most relevant studies in the literature with respect to evaluating dynamic performance and proposes a classification taxonomy for dynamic performance measurement frameworks according to five issues. These issues account for major sources of the inter-temporal dependence between input and output levels over different time periods and include the following: (i) material and information delays; (ii) inventories; (iii) capital or generally quasi-fixed factors and the related topic of embodied technological change; (iv) adjustment costs; and (v) incremental improvement and learning models (disembodied technological change). In the long-term, this line of research could contribute to a more efficient use of societal resources, greater level of maintenance services, and a highway and roadway system that is not only safe and reliable, but also efficient. / Ph. D.

Performance based contracting in the transportation arena is a rather recently implemented concept which has a few number of applications in the United States up to date. Nonetheless, the US Department of Transportation has vigorously promoted (by issuing memorandums to be distributed to the Highway Agencies and State Departments of Transportation) the conversion of traditional contracts to performance based contracts to reach a goal of 80% of the service contracts and actions being performance based by the end of fiscal year 2004 (Tomanelli 2003.) Virginia Department of Transportation (VDOT) has been one of the first state agencies that took the initiative of using a performance based contract for the maintenance of a portion of its interstate highway system. This initiative resulted in the establishment of the 'Comprehensive Agreement for Interstate Highway Asset Management Services' between VDOT and a private contractor in 1996 which resulted in the privatization of highway maintenance services. One of the important aspects of this contract related to this research is that it does not encompass any warranty clauses. In other words, the contractor does not provide any warranty to the VDOT for the services it is obligated to undertake. The contract is mute in this subject, making the contractor incur no liability for the underperformance of the maintenance activities. According to this research, this might lead to some cases which VDOT would not be willing to encounter. Just like performance based contracting, the use of warranties in highway contracts in the United States is a quite new concept which mainly dates back to 1995. There are different views possessed by different parties about the possible outcomes of implementing warranties in highway contracts. Nonetheless, this research proposes that the incorporation of warranty clauses into the VDOT issued performance based road maintenance contracts is vital to ensure the quality and durability of the work after the project completion. According to this research, warranty clauses, if developed carefully, give the contractor the motivation to implement superior maintenance practices to improve the overall conditions of the assets during the contract period. This is done in order to lengthen the life of each asset item and achieve the long term performance. Ultimately, the incorporation of warranty clauses is believed to reduce the risk imposed upon VDOT. Within the context of the discussion presented above, this research first illustrates that the complete satisfaction of one of the parties (VDOT) may be in question due to the absence of the warranty clauses within the contract, then lists and explores the benefits that would/may be gained by the incorporation of warranty clauses into the contract, and finally develops a warranty clause template and proposes it to be used in the future performance based road maintenance contracts issued by VDOT. At the bottom line, this study aspires to help the party in question (VDOT) to reduce the risk imposed upon it and to improve the future performance based road maintenance contracts it will issue. This research uses the VDOT contract as a baseline to define the problem and to propose a solution (i.e. the developed warranty clause template) for that. Nonetheless, some of the principles and approaches used during the development of the warranty clause template can also be referred to for the development of warranty clauses for the performance based road maintenance contracts issued by the other state DOTs. / Master of Science

Highway clients are increasingly concerned with the environmental consequences and sustainability implications of their highway maintenance service. This is because the service consumes a significant amount of natural resources, is financial and energy-intensive and is a large Greenhouse gas (GHG) emitter responsible for global warming and climate change. This has placed the highway maintenance sector, including its supply chain under increasing pressure to deliver well-maintained low-carbon maintenance service, whilst addressing its climate change impacts. The highway stakeholders increasing focus on carbon footprinting is a direct response to the legal obligation presented by the enactment of the UK s Climate Change Act (2008) and the Carbon Reduction Commitments. Investment decisions on highway infrastructure must now account for carbon and financial costs in a balanced manner. Highway clients now require their supply chains to demonstrate the capacity to reduce both direct and indirect carbon, and provide carbon footprint information relating to the work done or being tendered for. This is driving the sector to re-think its business operations within environmental, economic and social limits, which inherently presents risks and opportunities poorly understood by the stakeholders. It requires an in-depth understanding of the business operations, inputs and outputs. These business requirements are compounded given the lack of an agreed industrial methodology standard focusing on carbon footprinting, the knowledge and skill gaps, system boundary definitions, credible industrial data and their collection approach. The aim of this study is to develop a project-focused and process-based carbon footprinting methodology that includes a decision-support and carbon management tool to assist carbon management decision-making in highway maintenance planning and operation. This study then explored how the PAS2050 protocol can enhance the highway maintenance service delivery carbon footprinting and identify opportunities for reduction. It briefly reviews carbon emissions performance and the UK s highway maintenance sector, and developed a methodological framework that includes a carbon evaluation tool (the sponsor s business focus tool) based on the PAS2050 protocol. The framework developed is specific to highway maintenance planning and operation. It offers a carbon Life Cycle Assessment (LCA) tool that can identify emission hotspots across the process value chain, and inform a carbon reduction hierarchy. The implementation of the PAS2050-compliant methodology framework and the carbon evaluation tool for core highway maintenance processes (for example, pavement resurfacing, pavement marking, bulk lamp replacement and grass cutting), in addition to carbon footprinting across different site locations (urban, semi-urban and rural) are presented. The results indicate that materials production and their delivery to site (embodied carbon) are areas of carbon hotspots. This represents an important decision point for highway designers, managers and maintainers in order to deliver low-carbon service. These carbon hotspots suggest a less energy-intensive or green materials manufacturing process, responsible sourcing, use of recycled and secondary materials sourced locally (closer to sites) and delivered in bulk. The step-by-step carbon footprinting approach presented in this study is unique. It can be used by other sectors within the built environment as a pragmatic means of identifying and prioritising areas of potential carbon reduction through informed decision-making.