Incorporating Increased Road User Costs into Pavement Management Modeling: A Case Study of Two-Lane Rural Highways

The impact of increased road user costs on optimal pavement rehabilitation plans has been investigated using a simplified pavement management model. The increased road user costs include elevated vehicle operating costs (VOCs) due to work-zone lane closures and traveling on severely deteriorated pavements. A model is proposed for estimating the VOC for work-zone lane closures on two-lane rural highways, considering both stopping and idling costs. Another model for approximating the increased VOC associated with driving on poor/bad pavements is suggested as a function of the relevant VOC rate and a proportionality factor. Sample results are presented for a two-lane rural pavement network comprising 54.2 lane-kilometers. The sample optimal rehabilitation plans derived, excluding increased VOC, are associated with substantially higher VOC due to driving on severely deteriorated pavements. The inclusion of increased VOC because of badly damaged pavements has resulted in an improved pavement network without incurring extra expenses for highway agencies. The annual budget required to eliminate the VOC resulting from severely damaged pavements is $2.5 million while neglecting increased VOC, which decreases to $1.5 million when accounting for increased VOC. The incorporation of increased VOC has shifted fund allocation more towards substandard pavements. The optimal rehabilitation plan is associated with a $1.0 million annual budget, yielding a maximum road user saving of $0.411 million.