Cost effectiveness evaluation of rigid and composite highway pavement routine maintenance.

摘要

This dissertation deals with the evaluation of three issues related to routine maintenance of highway pavements. These are: (1) whether and how much routine maintenance has an impact on the pavement's serviceability and/or expected service life; (2) whether seal coating practice is cost-effective, and what is the optimal timing for this activity; and (3) what directions, principles and criteria should be used for chip and sand seal coating activities on Indiana state highway system.;The first issue was evaluated using before/after statistical comparisons; the means of indicators for groups of roadway sections receiving maintenance and groups not receiving maintenance were compared to determine if the differences in the means were statistically significant. The results were subjected to engineering judgement in order to verify if the conclusions are justifiable or not. General linear regression models were then used to quantify the impacts. The second issue was evaluated by using a life cycle costing approach. The costs included in the evaluation covered annual routine maintenance costs, seal coating costs, and resurfacing costs at the end of lifecycle. The third issue was dealt with utilizing a number of techniques: an expert opinion survey, a comparative evaluation of practices in other jurisdictions, and telephone interviews and focused group discussions.;Testing of significance yielded three groups of findings: the first group contained activities that demonstrated a "definitely significant" impact on either roughness measurements, pavement serviceability ratings, or both; the second group, activities that demonstrated a "marginally significant" impact on the condition indicators listed above; and the third, activities that could not be confirmed either way.;Life cycle costing illustrated that seal coating is more of a stop-gap measure allowing greater flexibility in capital spending than a cost-effective solution to problems.;The developed policy guidelines included a general statement on when and where seal coating should be applied; a set of principles that defined which types of roads should receive priority; and a decision tree to assist in making decisions on specific projects.;The study recommended a three finger strategy for the improved definition of the effectiveness of maintenance activities. A component of this strategy is the undertaking of a series of controlled experiments whose design was provided.