Speed choice behaviour-based methodology for evaluating the effects of pavement roughness on travel time cost and discomfort cost

ABSTRACT

Evaluating the effects of pavement roughness on the travel time cost (TTC) and the discomfort cost (DCC) is essential for user cost estimation in road maintenance planning and for benefit assessment of investments on maintenance. However, existing related studies are quite limited. The main obstacles are the lack of well-defined mechanisms to (i) understand the riders’ speed choice behaviour and (ii) quantify the riding discomfort cost. To narrow this gap, a new method is developed in this study to evaluate the incremental TTC and DCC caused by roughness increasing. By representing the ride quality and the roughness with ‘jolt’ and the international roughness index (IRI), respectively, a ride quality indifference curve (RQIC) is developed. Then, using the RQIC and the traffic flow fundamental diagrams before and after an IRI increase, the riders’ speed choice behaviour is modelled. The selected speed after the IRI change is explained as the balancing result between efficiency and comfort that satisfies the proposed marginal principle. Applying this principle, the procedures to calculate the TTC and DCC increments are designed. Finally, a application example of the method is presented. The method proposed herein mainly contributes to the user cost estimation in the post-evaluation of the road maintenance.

KEYWORDS:

• Pavement roughness
• vehicle speed
• travel time cost
• discomfort cost
• speed choice behaviour
• ride quality indifference curve

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [grant number 51208379] and the Scientific Research Program of Shanghai Municipal Science and Technology Commission [grant number 16DZ1203602].