Consideration of pavement roughness effects on vehicle-pavement interaction

Abstract

Paper presented at the 20th Annual South African Transport Conference 16 - 20 July 2001 "Meeting the transport challenges in Southern Africa", CSIR International Convention Centre, Pretoria, South Africa. ABSTRACT: Current mechanistic pavement design and analysis techniques use several simplifications to enable the process to be practical and cost-effective. These include equivalent vehicle loads, linear elastic analysis and static vehicle load and pavement response analysis. These simplifications allow the process of pavement design and analysis to be applied by the majority of engineers, but cause the process to be less related to real life. In a project performed at CSIR Transportek an investigation was done to establish the effects of incorporation of moving dynamic traffic loads in pavement design and analysis. The objective of this study was to identify parameters to be included in vehicle-pavement interaction analyses and to establish the expected effects of such analyses. In previous papers the background and major findings of this study were reported. In this paper the focus is on quantification of the pavement roughness effects on the calculated structural pavement life and the effects of surfacing maintenance on the moving dynamic tyre loads generated by vehicles. A simplified method for calculating the moving dynamic tyre load population is used together with standard pavement response analysis methods to quantify the effects of pavement surfacing maintenance on roughness and structural pavement life. This method can be used as a pavement management system tool to enable quantified decisions regarding different surfacing maintenance options. The aim of this paper is to present some of the results of the vehicle-pavement interaction project, mainly in terms of the expected effects of pavement roughness on the moving dynamic effects in pavement analysis and design. Background is provided of the study and previous reported results. This is followed by a summary of the important vehicle and pavement parameters to be included in the analysis. Examples of the model where these parameters are included are provided. Finally, conclusions and recommendations around the effects of pavement roughness on moving dynamic load effects in pavement analysis and design are provided.