正交异性钢桥面沥青混凝土铺装层荷载图式研究

Research on the Loading Pattern of Asphalt Pavement on Orthotropic Steel Deck

钢桥面铺装荷载图式是钢桥面铺装力学分析的基础。利用三维有限元方法对265/70R19.5(11.00R20)轮胎与正交异性钢桥面铺装的接触过程进行了模拟,计算出了轮胎与铺装接触的平面分布以及接触区域内应力的分布特性。研究结果表明:轮胎与铺装接触区域的平面形状以及接触区域垂直应力分布等都随着汽车荷载的变化而变化;当汽车轴载超过100kN时,轮胎与铺装接触区域的平面形状近似为矩形;当轮胎作用于正交异性钢桥面U形加劲肋腹板顶面时,轮胎与铺装层接触区域的垂直应力横向分布接近于"凸"形,当轮胎作用域正交异性钢桥面板U加劲肋腹板之同时,接触区域的垂直应力横向分布接近于马鞍形。在钢桥面铺装力学分析时选用双矩形荷载能够较好的模拟轮胎与铺装接触平面的实际状况,而轮胎荷载的横向分布应该综合考虑轮胎作用最不利位置之后决定。

Loading pattern is the basis of mechanical analysis of steel deck pavement.In this paper,3-D FEM was used to simulate the contact process between tire(265/70R19.5)and deck pavement.The characteristic of contact area and stress distribution was stud- ied.The results show that the contact area and stress between tire and pavement vary with the vehicle axle loading.When axle load- ing reaches 100kN,the contour of contact area is approximately rectangle;and when the tire is above the web of U stiffeners,the distribution of uprightness stress in the contact area is near peak type,and when the tire is on the pavement between webs of stiffen- ers,the distribution of uprightness stress is near concave type.Therefore,double rectangles loading pattern can simulate the contact between tire and pavement better than others,and the loading density should be chosen after the unfavorable position of the tire is considered properly.