高架快速路沥青桥面铺装结构力学分析

Structural Mechanical Analysis of Asphalt Bridge Deck Pavement of Expressway

摘要:

城市高架快速路沥青桥面铺装具有特殊的使用条件与受力变形特点，易导致剪切破坏、开裂、坑槽及修补、表面变形等病害。为了提升铺装结构安全和耐久性能，建立了高架快速路沥青桥面铺装的三维有限元模型，研究荷载、水平力、铺装层厚度与模量变化对桥面铺装力学响应的影响。研究结果表明：随荷载增大，铺装结构层内应力应变均线性增大，可能导致铺装层开裂、层底开裂、车辙等病害；水平力的增大会使铺装层剪应力大幅增大，易导致滑移和失稳性车辙；推荐桥面铺装沥青层厚度范围为6～10 cm；疲劳开裂、层间滑移是桥面铺装结构的主要病害，可采用表面拉应力和层间剪应力作为设计指标进行控制。

Abstract:

The asphalt bridge deck pavement of urban elevated expressway has the special service conditions and stress deformation characteristics, which can easily lead to shear failure, cracking, pothole and repair, surface deformation and other diseases. In order to improve the safety and durability of pavement structure, a three-dimensional finite element model of asphalt bridge deck pavement of elevated expressway is established to study the effects of load, horizontal force, pavement thickness and modulus on the mechanical response of bridge deck pavement. The results show that with the increase of load, the stress and strain in the pavement structural layer increase linearly, which may lead to pavement cracking, layer bottom cracking, rutting and other diseases. The increase of the horizontal force will greatly increase the shear stress of the pavement layer, which will easily lead to slip and unstable rutting. The recommended thickness range of the asphalt bridge deck pavement is 6~10 cm. Fatigue cracking and interlayer slip are the main diseases of bridge deck pavement structure, which can be controlled by surface tensile stress and interlayer shear stress as design indexes.