荷载形状对钢桥面铺装力学响应的影响

针对轮胎接地形状的不规则性,构造理想传力垫层、运用三维有限元接触分析方法分析了矩形、椭圆、长圆3种简化荷载形状在具有不同单轮横向宽度及两轮中心距时铺装层的力学响应。结果表明单轮横向宽度与两轮中心距对横向拉应变有较大影响,而矩形形状荷载计算结果较椭圆和长圆形状荷载小。与实测数据的对比分析表明:以往计算采用的单轮横向宽度偏小,长圆荷载的计算结果与实测值更接近,在用简化矩形均布荷载分析钢桥面铺装力学响应时,单轮横向宽度与两轮中心距应该尽量按实际情况选取,并进行荷载形状修正。

Effects of Load Shape on Mechanical Response of Orthotropic Steel Deck Pavement

The contact shape between the tire and pavement exhibits a highly irregularity.On the basis of abundant literature,three types of simplified load shapes with variable width and center-to-center distance are put forward.3D FEM of contact analysis is established,and the pavement response under all kinds of load shapes is obtained.It is found that width and center-to-center distance of load shape is remarkable to the results,and the transverse tensile under rectangle load is smaller than those of other two shapes.Comparison between computation and test data shows that the results of round-ended rectangle shape is closer to the test data,and the load width used before is too small.So,for analyzing orthotropic steel deck pavement of super-long-span suspension bridges,if simplified rectangle load shape is used,width and center-to-center distance of the load should be adopted according to the actual dimension as far as possible,and the load shape should be corrected.