NCHRP 17-09(2) [Completed]
Impacts of Resurfacing Projects With and Without Additional Safety Improvements
| Project Data
Design standards are considered essential to highway safety and the application of the highest design standard is thought to maximize safety. Safety needs to be considered in making decisions on resurfacing projects because a smoother pavement often results in higher speeds on a facility. Further, attempts to stretch limited resurfacing funds often reduce the type and scope of additional safety improvements. Limited research has been done to determine the safety impact of resurfacing projects with and without additional safety improvements. It is desirable to determine the safety impacts to provide information to decision makers on the importance of safety improvements associated with resurfacing projects. The project is critical because of the great number of resurfacing projects, the lack of specific guidance for the design engineer (particularly in state and local agencies), and the continuing pressure on agencies to optimize the use of limited resources for transportation improvements. Huaer, Terry, and Griffith (1994) examined the accident effect of resurfacing alone and resurfacing in combination with a certain set of safety improvements for the state of New York. The empirical Bayesian analysis methodology employed in that study may be applicable to this project. It is necessary, however, to cover more improvement packages and to extend its scope nationwide. In addition, the analysis methodology should explicitly consider that the roadway condition prior to resurfacing may display a wide variety of needs from a safety standpoint.
The objectives of this research were (1) to identify the major categories of safety improvements implemented in conjunction with the resurfacing of two-lane roads; (2) to document, relative to the conditions before the project, the accident impact of resurfacing and of resurfacing in conjunction with the major categories of safety improvements; and (3) to present data comparing pre- and post-improvement accident experience for the various improvement categories. To accomplish the above objectives, the following tasks were conducted: (1) Critically review the New York State study conducted by Huaer, Terry, and Griffith. Review other research related to the safety effects after the resurfacing of two-lane roads. Contact state and local agencies to identify the nature and extent of their policies and programs associated with two-lane road resurfacing. (2) Develop a draft experimental plan for an in-depth analysis of the safety impacts associated with resurfacing two-lane roads that focuses on the impact of categories of improvements that may be associated with resurfacing projects stratified by ADT. (3) Contact agencies having the necessary data resources and solicit the cooperation of agencies in a minimum of seven states to participate in the study. (4) Prepare an interim report which describes the relevant research, summarizes agency practices, details the final experimental plan, identifies the candidate agencies to be included in the study, and presents examples of how the results may be presented. (5) Collect data in accordance with the experimental plan. (6) Perform the appropriate statistical analysis of the data in accordance with the experimental plan. Identify the impacts of specific categories of improvements on safety after resurfacing in the analyses and including appropriate measures of confidence. (7) Prepare a brief informational summary of the findings of this study for use by decision makers. (8) Prepare a final report documenting the efforts, analyses, database, interpretations, and conclusions of the research.
Status: The project has been completed.
Product Availability: NCHRP Research Results Digest 255, which summarizes the results of this project, is available from the NCHRP.