斜交板沿横坡的下滑与平面内转动的成因分析

通过建立斜交板在缓慢外爬过程中的几个典型受力模型,并根据前一阶段受力模型的变位及受力结果,给定后一阶段受力模型的边界条件,尝试找到斜交板在间歇性荷载及自重沿横桥向分力的作用下不断外爬,并在平面内转动的成因,发现利用盖梁形成的横坡造成斜板面内的下滑,由下滑导致斜交板沿桥轴向两边约束产生差异,进而诱发斜交板的面内转动。最终模型的变位结果与塘河大桥实桥出现的问题相一致,表明通过建立典型受力模型逐次迭代锁定最终受力状态的方法对于确定斜交板爬移成因是有效的。

Analysis of Causes of Oblique Slab's Slide and Rotation within Surface

By building several typical mechanics models of oblique slab, this paper tries to find the causes of oblique slab's slide and rotation within surface when it is under the component force along the direction of the cross-fall and generated by the intermittence load. It showes that coping's cross-fall caused oblique slab's slide; the slide made boundary condition of two terminal along the bridge's axis different from each other and going step further to induced slab's rotation within surface. The displacements result of the last model are in good agreement with the problems presented by Tanghe Bridge, it demonstrates that, on the base of building typical mechanics models, the method of varied step and gradual iteration is an efficient method to lock the last mechanics model of oblique slab.