Author: M. Stroup Gardiner

Publisher:

Published: 2003

Total Pages: 24

ISBN-13:

In 1989 the Alabama Department of Transportation (ALDOT) added a policy to their smoothness specification that enables payments made to paving contractors to be based on the level of smoothness. The contractor can receive a 5% bonus for above average or a 5% penalty for below average smoothness readings. The measurement of smoothness has been based on the manual extraction of data from profilograph traces based on a 0.2 blanking band and resolution of 0.05. ALDOT has determined that more than three-quarters of all the 0.1 mile segments tested since the implementation of the specification have fallen in the 5% bonus range without an improvement in pavement ride quality. This observation resulted in the decision to conduct a study to determine; 1) if the ProScanTM hardware and software could be used to provide a reliable method of reducing profilograph traces, and 2) to investigate the feasibility and consequences of different smoothness pay factors. The results of the study support the ProScanTM system as a quick, accurate, and replicable method of reducing the profilographs. In addition, it was concluded that ALDOT should change the blanking band to a width of 0.0 and should adopt a combined step and continuous function method of determining incentive pay factors. With these pay factors in place ALDOT would have paid only 96.8% of the bid price for paving projects that brought 102% pay under the old step-wise function.