Sensitivity Analysis of Various Cost Elements in Flexible Pavement Design

This paper presents a method for predicting the optimum initial service life and optimum periods of resurfacing for flexible pavements. The method is based on consideration of total pavement costs including the cost of initial construction, routine maintenance and major maintenance and increased road user costs resulting from the maintenance operations. Standard economic analyses techniques were used for determining the average annual cost of alternate designs. A modification of the Radzikowski model was used for estimating routine maintenance cost of flexible highway pavements. The pavement design method developed by the Corps of Engineers was utilized in estimating initial design as well as required major maintenance (resurfacing) . A method was developed which presented an estimation of road user cost due to maintenance and resurfacing operations. Variables evaluated in this paper included (1) subgrade type, (2) initial traffic volume, (3) rate of traffic growth, and (4) rate of interest on the investment. Solutions were made for both 2-lane and divided 4-lane highways. The results of the study are presented in the form of graphs which indicate the initial design period which results in least cost for combinations of the variables given.