轮胎作用下钢-混组合梁桥面铺装动态响应

Dynamic Response of Bridge Deck Pavement Layer of Steel-Concrete Composite Continuous Beam Under Tire Loading

钢-混组合连续梁桥面铺装层受力十分复杂,桥面铺装层早期破坏与其车辆荷载的动态响应密切相关。建立了实体橡胶轮胎和三跨钢-混组合连续梁模型,轮胎采用Yeoh模型,桥面铺装材料(沥青混合料)采用广义Maxwell模型,将整车后轴悬架动态力施加于橡胶轮胎,求解桥面各铺装层垂向挠度、垂向应力、纵向应力、横向应力及位移谱,并且与移动荷载进行比较。结果表明:三跨钢-混组合梁的每跨垂向挠度比移动荷载大21.3%,4.7%,8%,纵梁垂向挠度比桥面铺装层小8.9%;上面层与水泥混凝土层应力变化趋势相似,下面层应力比较复杂;上面层位移响应频率集中于0~6 Hz范围。文中数据对桥面铺装层结构优化具有较大指导意义。

The stresses of the pavement systems of the steel-concrete composite continuous beam deck are very complicated,and the early damage of the deck pavement systems is closely related to the dynamic response under the vehicle load. A rubber tire finite element model and a three-span steel-concrete composite continuous beam model are established in this paper. The rubber tire adopts the Yeoh model,and the bridge deck pavement material(asphalt mixture)adopts the generalized Maxwell model. Moreover,the dynamic force of the rear axle suspension of the vehicle is applied to the rubber tires. The vertical deflection,vertical stress,longitudinal stress,transverse stress,and displacement spectrum of each pavement layer of the bridge deck can be solved comparing with the moving load. The results show that the vertical deflections of each span of the three-span steel-concrete composite beam are 21.3%,4.7%,and 8.0%,respectively,larger than the moving load under the action of tire rolling;the vertical deflection of the longitudinal beam is 8.9% smaller than that of the deck pavement. The stress change trend of the upper layer is similar to that of the cement concrete layer,and the stress changes of the lower layer are more complicated. The displacement response frequency of the upper layer is concentrated in the range of 0~6 Hz. The above data have great guiding significance for structural optimization of bridge deck pavement.