Tire-Pavement Contact Stress Characteristics and Critical Slip Ratio at Multiple Working Conditions

Minrui Guo,Xinglin Zhou

doi:10.1155/2019/5178516

Abstract

The contact stress distribution of tire-pavement is generally assumed to be uniformly distributed in circles or rectangles in the pavement design. This simplification can solve some common engineering problems, but it neglects two factors including magnitude and direction of the contact stress. The main purpose of this paper is to analyze the contact stress distribution between the bus tire and the pavement under different driving conditions and pinpoint and compare the critical slip ratio during braking and acceleration. First, a tire-pavement simulated contact model is constructed by ABAQUS. Next, we compare, respectively, contact stresses in the vertical, longitudinal, and transverse directions at various rolling conditions and analyze the longitudinal forces at different slip ratios during braking and acceleration. It is observed that the magnitude, direction, and nonuniform distribution of contact stress are affected by the multiple working conditions while the bus is working. Meanwhile, in the braking and acceleration conditions, the longitudinal force grows rapidly as the slip ratio increases, and then grows slowly and at last decreases when the critical slip ratio is reached. However, the critical slip ratio at the time of braking differs from that at the time of acceleration, and the former is smaller than the latter.

Highlights

Tires are the important part of vehicles in different driving conditions, which carry the load transfer between the vehicle and the ground, thereby creating various contact stresses and forces in the tire-pavement contact area [1,2,3,4]
E truck tire was modeled by Wang et al [6] to simulate the contact stress under static and different driving conditions. ey found that measured and predicted vertical contact stresses and tangential contact stresses are nonuniform. ey found that when the truck traveled at speeds of 10 km/h or 30 km/h under braking condition, the critical slip ratio at both speeds was equal to approximately 10%, and the friction force reached its maximum [7]
In this study the critical slip ratio of the accelerated state was not analyzed. e shear stress distribution characteristics of racing tires were influenced by carcass deformation, and the contact stress of tire pavement under braking condition was analyzed in detail by Gruber and Sharp [8]. e established model could be used to evaluate the shape of the contact area of the tire and the rolling radius

Summary

Introduction

Tires are the important part of vehicles in different driving conditions (free rolling, acceleration, braking, and turning), which carry the load transfer between the vehicle and the ground, thereby creating various contact stresses and forces in the tire-pavement contact area [1,2,3,4]. E shear stress distribution characteristics of racing tires were influenced by carcass deformation, and the contact stress of tire pavement under braking condition was analyzed in detail by Gruber and Sharp [8]. E three-dimensional stress distribution of heavy-duty truck tires under various rolling conditions was obtained, and it pointed out that the critical slip ratio was around 18%, the braking force reached its maximum [10], whereas the critical slip rates for acceleration and braking state were not compared. E longitudinal forces of the tire under different loads and inflation pressures were analyzed under different rolling conditions It could be obtained from the above literature analysis that the contact stress characteristics of the truck tires, racing tires, heavy-duty truck tires, and wide-base tires were analyzed. The contact stress characteristics of the bus tires under multiple

Objectives

Methods

Findings

Conclusion