Impact of a Smoothness Incentive-Disincentive on Hot-mix Asphalt Maintenance Resurfacing Costs

About the report:

Smoothness, the absence of bumps and dips in the riding surface of a pavement, improves the quality of the ride and is believed to prolong the life of the pavement. This research addressed the impact of potential pay adjustments for smoothness on maintenance contract prices for hot-mix asphalt. In addition to the construction costs associated with potential incentives/disincentives for smoothness, the research examined the financial value of the resulting product (presumably smoother pavements). The analysis included maintenance cost savings for the owner/agency, as well as any reduction in delay and operating costs for the motoring public. A detailed statistical analysis of 5 years of Virginia's plant mix resurfacing schedules found no statistically definitive impact on bid price as a result of the Virginia Department of Transportation's (VDOT) special provision for rideability for asphalt pavements. A similar analysis on a more focused data set, however, did document a lifetime reduction in the International Roughness Index (IRI) of almost 9 in/mi. This reduction in roughness (increase in smoothness) implies an increase in pavement service life, which translates into reduced annual maintenance costs. Although the analysis supports as much as 7 years in additional functional life, an example calculation demonstrates that just a 2-year life extension will supply approximately $1,295 (about 6% of material costs) in owner/agency savings for every lane-mile of highway that is resurfaced under the special provision for rideability. If VDOT continues to employ the special provision with the frequency it has averaged over the past 4 years (1,033 lane-miles per year), using the special provision will save on the order of $1.3 million per year. The lifetime decrease in roughness can lead to even more dramatic user cost savings. One real example provided in the report demonstrates a fuel cost savings (for trucks alone) of $160,000 over a 10-year period for each lane mile of highway that is resurfaced under the special provision for rideability.

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