半刚性基层沥青路面层间接触临界状态值的计算方法

为了准确地模拟实际道路结构层的层间接触状态,计算荷载下道路结构层真实的应力、应变响应,采用分形理论和层间接触理论,对半刚性基层沥青路面层间接触状态进行微观分析;在此基础上建立了路面结构的层间接触模型,根据级配分形维数值的公式计算了沥青面层、半刚性基层层间接触临界值的大小.分析结果显示:在其他条件保持恒定的情况下,当层间有效接触面积大于临界值时,微观无数大小不同的接触点将处于弹性状态,宏观上路面结构表现出弹性性质;当层间有效接触面积小于临界值时,微观无数大小不同的接触点将处于塑性状态,宏观上路面开始发生塑性损伤变形.提出了依据级配计算路面结构层间接触状态值的方法,可以纠正我国道路结构设计规范里基于线弹性层状理论,假设层间接触完全连续或完全光滑与工程实践存在明显偏差情况,从而更清晰的分析路面微观结构与宏观路用性能之间关系.

Analytical method of interlayer contact fettle in semi-rigid-base bituminous pavement

In order to simulate actual road structure layers contacts state more accurately and to exactly calculate road structure layer true stress and strain response,fractal characteristics theory and interlayer contact theory were integrated to analyze the microstructure fettle in semi-rigid-base bituminous pavement.Then a pavement structure interlayer contact model was established on this analysis.Under the grading fractal dimension formula,the critical fettle numerical value was calculated between the asphalt surface and semi-rigid base.The results show that the pavement structure stays in elastic states if the interlayer contact effective area is bigger than the critical value.Contrarily,the pavement begins to effect plastic deformation damage.A fix-quantify calculation method of road interlayer non-linearity contact is also proposed.This calculation method can be used to correct the significant deviations between engineering actualities and our country's road structure design specification.The interlayer contact fettle is assumed in absolute continuity or absolute smoothness states in the design specification.The relationship between pavement microstructure and pavement performance can be analyzed more precisely by this method.