Response Analysis Of Cement Concrete Pavement Under Dynamic Load In Heavy Traffic

Cement concrete pavement is the main form of highway pavement structure in our country. As our comprehensive national strength further enhanced, basic construction has made new achievement, especially transportation industry is developing rapidly. At the same time, there are many problems in our country traffic situation. First, the pavement indicators of Chinese current specification are static loads, but in the actual situation, the vehicle drives on the road at a constant speed. The value and position of dynamic loads exerted on the rode change with time. The actual stress state of the road and the stress state under static load exist certain differences. Second, in the transport vehicles, which the proportion of heavy-duty vehicle and super heavy-duty vehicle takes is increasing, vehicle overloads problem has been increasingly outstanding, and the early damage of cement concrete pavement is serious. So the dynamics analysis of overloaded traffic pavement structure has important theoretical significance and application value.In this paper, according to the characteristics of heavy traffic, basing on generalizing research results at home and abroad, by using finite element analysis theory, the cement concrete pavement structure modeling as an elastic system, and establishing threedimensional finite element analysis model with ANSYS software, the vehicle load simulating the steady-state sinusoidal moving loads, at different overload rates, to analysis the response under the case of traveling load under the state of uniform motion, acceleration motion and braking deceleration motion which considering horizontal loads, obtaining the time history curve of deflection, longitudinal stress, vertical normal stress, horizontal shearing stress in each layer pavement. And by comparing the results, to determine the overload influence on accelerating load damage.The results show, maximum deflection, maximum longitudinal compressive stress, maximum transverse compressive stress, maximum vertical normal stress and maximum horizontal shearing stress, are appeared in the road surface, but maximum longitudinal tensile stress and the maximum transverse tensile stress are appeared in the pavement board. And with the overloading rate increasing, the pavement structure stress and deflection are constantly increasing. And with the increase of the overload ration, the pavement stress and deflection are increasing. Visibly, the phenomenon of overloading trucks in overloaded road is important reason of pavement structure damage.