冲击碾压改建水泥混凝土路面时基层的受力特性研究  

Mechanical characteristics of pavement base under impact compacted load

作　　者：胡昌斌[1] 阙云[1] 

机构地区：[1]福州大学土木工程学院,福建福州350108

出　　处：《福州大学学报（自然科学版）》2009年第5期742-747,共6页Journal of Fuzhou University(Natural Science Edition)

基　　金：国家自然科学基金资助项目(50908056);福建省自然科学基金资助项目(2009J01249);福建省高等学校新世纪优秀人才计划资助项目(TW2006-27)

摘　　要：基于三维动力弹塑性有限元分析方法,对冲击压路机沿面板纵向中线及板边两种行驶路线,冲击碾压破碎旧水泥混凝土板时,路面板下基层的变形、受力及破坏特征等力学响应进行了分析.研究发现,冲击碾压施工时基层对于路基有应力扩散作用,基层整体上与路面板一起处于纵、横弯曲状态,变形特点与面板一致,不利于面板破碎.沿边线路的基层竖向变形明显大于板中线路,基层顶面水平应力基本为压应力,底部为拉应力.两种线路下基层底面均出现塑性破坏,呈底部弯拉破坏模式,表面应力变形最大值位于板角或板边缘下方.随着冲击遍数的增加,底部塑性破坏区域逐渐增大.冲击初期基层先于面板破坏,从而使面板逐渐破碎,同时路基受到更大压实功.建议在冲击能量较小和基层较刚时,先沿板边冲击破坏基层,然后逐步沿中部移动,将可获得更高的施工效率.The deformation,stress and failure characteristics of pavement base under two impact loading routes were analyzed based on three dimensional elastic-plastic dynamic FEM.The results indicate that pavement base plays the role of stress dispersion.Pavement base and pavement slab were in bending state and deformation characteristics of pavement base consistent with pavement slab.So,it is adverse for pavement slab to be cracked.Vertical deformation of pavement base along route of slab edge is larger than that along route of slab edge. Top surface of pavement base is in compression state and bottom surface of pavement base is in tension state. Plastic zone will appear at bottom of pavement base in two routes and pavement base appear to bending - tensile failure. The maximum stress and deformation are located at inferior section of the corner of slab and the edge of slab. Plastic zone of pavement base increases gradually with the increasing times of impact compaction. In the initial stage of impact compaction, the failure of pavement base is precede to that of pavement slab. Subsequently, pavement slab tends to be cracked gradually. In order to obtain more higher construction efficiency, it is reasonable to impact edge of pavement slab at the initial period and the route of impact compation should move gradually to the center of slab.

关 键 词：冲击碾压 水泥混凝土路面 基层 动力有限元 

分 类 号：U416.216[交通运输工程—道路与铁道工程]