超重载作用下沥青路面结构设计研究

Research on Design of Asphalt Pavement Structure Under Over-load

针对城际铁路车辆段场区路面荷载的特殊性,为考虑超重载车辆对路面结构稳定性的瞬时影响,首先通过分析超重载车辆的轴载分布特点,得出该类车辆的轴载参数;其次根据弹性层状体系理论,提出了超重载车辆通行场区路面结构设计指标与方法;最后对拟定路面结构进行标准轴载条件和超重载条件下的路面结构验算,从而验证了路面结构方案的合理性。研究结果表明,当道路有超重载车辆通行时,路面结构设计应补充分析超重载车辆作用下的半刚性基层层底拉应力、沥青层剪应力,通过调整路面结构组合,确保这2项指标分别小于半刚性基层材料劈裂强度与沥青层材料60℃抗剪强度,避免路面过早出现结构性破坏。该研究成果为城际铁路车辆段超重载车辆通行场区的路面结构设计优化提供了借鉴。

In view of the particularity of the road load in the depot area of the intercity railway,the axle load parameters of over-load vehicles are obtained by analyzing the distribution characteristics of the axle load of over-load vehicles to consider the instantaneous impact of over-load vehicles on the structural stability of the road;Secondly,the design indicators and methods for the pavement structure of over-load vehicle traffic areas are proposed by elastic layered systems theory;Finally,under the standard axle load and over-load,the proposed pavement structure calculation was conducted to verify the rationality of the pavement structure scheme.The research results indicate that when overloaded vehicles pass on the road,the pavement structure design should supplement the analysis of the tensile stress at the bottom of the semi rigid base layer and the shear stress of the asphalt layer under the action of overloaded vehicles.By adjusting the pavement structure combination,it is ensured that the distribution of these two indicators is smaller than the splitting strength of the semi rigid base layer material and the 60℃shear strength of the asphalt layer material,respectively.The structural damage is avoided.This research achievement provides reference for the optimization of pavement structure design in the area of over-load vehicles passing through the intercity railway depot.