荷载接触形式对路面结构力学指标的影响分析  

Influence of Contact Form of Load on Mechanical Index of Pavement Structure

作　　者：颜可珍[1] 赵晓文[1] 石挺巍 刘俊[1] 

机构地区：[1]湖南大学土木工程学院,湖南长沙410082

出　　处：《重庆交通大学学报（自然科学版）》2017年第4期23-29,共7页Journal of Chongqing Jiaotong University(Natural Science)

基　　金：国家自然科学基金资助项目(50808077;51278188)

摘　　要：传统沥青路面结构力学模型通常将车辆荷载假定为圆形、椭圆形、矩形,与实际路面结构在非均布荷载作用下的真实受力状态有一定的区别。应用3D-Move Analysis有限层软件,建立黏弹性材料特性下力学响应模型,对比分析了静载和动载情况下,不同荷载接触形式对路面结构剪应力、路表弯沉、面层底部拉应力、土基顶部压应变最大值及位置的影响;分析了水平力系数和轴载变化时,各指标最大值的变化规律。结果表明:不同荷载状态、荷载接触形式作用下,各力学指标最大值及位置有较大的区别;汽车匀速行驶时,按照传统静载计算结果进行力学指标设计是偏于安全的;汽车制启动时,计算结果比静载偏大,并随着水平力系数的增加持续增大,仍按传统静载结果设计容易导致车辙、疲劳开裂等早期损坏现象;不同荷载接触形式,各力学指标均随轴载的增加而增大。In traditional asphalt pavement structure mechanical model,the vehicle load was usually assumed as round,oval,rectangular,which had a certain difference with the actual pavement structure under non-uniform load of the real stress.Finite layer software 3D-Move Analysis was applied to set up the mechanical response model with viscoelastic material properties.Influence of different load contact forms on the shear stress of pavement structure,the road surface deflection,the tensile stress at the bottom of surface and the maximum compressive strain and position of subgrade top was comprised and analyzed under static load and dynamic load.The variation rule of the maximum value of each index was analyzed,when the horizontal force coefficient and axial load was changed.The results show that the maximum value and position of each mechanical index is quite different under different load state and contact form of load.When the vehicle drives at a constant speed,the mechanical index design in accordance with the traditional static load calculation is inclined to be safe.When vehicle brakes and starts up,the calculation result is larger than that with static load,and it continuously increases with the increase of horizontal force coefficient.Therefore,the design still according to the traditional static load results easily causes early damage phenomena such as rutting and fatigue crack.With different contact form of load,all mechanical indexes increase with the increase of axle load.

关 键 词：道路工程 荷载接触形式 有限层方法 力学指标 

分 类 号：U416.01[交通运输工程—道路与铁道工程]