This study was conducted to develop methodologies for appropriately determining the monetary values of I/D rates of highway construction projects in Indiana. In this study, a comprehensive literature review was performed to identify possible effective methodologies for work zone effects, construction impacts, and contract time optimization. The highway production rates were developed in a previous study. The production rates were validated and adjusted with the help from INDOT field engineers. The weighin- motion (WIM) collected traffic data were obtained, processed, and analyzed to provide input data for user cost calculations at highway work zones. Construction data were obtained and processed to develop the relationship between the construction cost and construction time. With the traffic and construction data, the methods for user cost calculations were developed as the basis of determining appropriate I/D rates. User costs resulting from traffic delays at Indiana highway work zones were analyzed. A series of equations for estimating user costs at work zones were developed. User cost calculation sheets using MS Excel were developed based on the traffic data on Indiana highway network. Finally, a method was developed to determine I/D rates based on the relationship between construction cost and construction time in combination with the estimated user costs at given work zones. Guidelines for developing A+B bidding and I/D provisions were provided.

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Highway construction, incentive/disincentive, A+B bidding, contract time, user costs., SPR-3080

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Performing Organization

Joint Transportation Research Program

Publisher Place

West Lafayette, Indiana

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