Investigation of impact of wheel wander on pavement performance

Abstract

The procedures in Mechanistic-Empirical Pavement Design Guide (MEPDG) and Caltrans software program using Mechanistic-Empirical (CalME) methodologies to address wheel wander are relatively simple and based on dividing the wheel wander distribution into a number of segments (say five) of equal areas. Such approaches suffer from a major limitation that the selection of equal segments is arbitrary, and can, therefore, lead to biased results relative to realistic transverse wheel wander distribution. The proposed Monte-Carlo simulation scheme provided cumulative distribution functions for all the critical responses and they in turn were used to estimate pavement performance (or life). The investigation covered a variety of pavement factors that significantly affect pavement performance or life. The factors included are: (1) pavement layer configuration (thin and thick); (2) pavement material properties (unmodified and polymer-modified asphalt mixture); and (3) tyre configurations (dual and wide-base). In this paper, the focus has been on the description of the proposed approach and its application in two of the important modes of failure in asphalt concrete pavements: fatigue cracking (top-down and bottom-up) and rutting. The required traffic-induced pavement strain database needed in the pavement performance investigations was developed using the 3D-Move analysis software. The proposed approach is more appealing than current procedures (e.g. MEPDG and CalME) since the pavement response distributions were derived statistically. The pavement design information presented are in the form of data sets that the pavement engineers and researchers can readily use to assess the impact of wheel wander in terms of many important factors such as pavement layer configuration, non-uniform tyre contact distribution, vehicle speed, etc., that affect long-term pavement performance.

Keywords:

• Monte-Carlo simulation
• flexible pavement
• viscoelastic modelling
• probability distribution functions of response
• pavement life

Disclosure statement

No potential conflict of interest was reported by the authors.