Abstract: The damage condition of existing obliques slab bridge demonstrates that most of them would de and rotate within the surface.Based on the damage features of Tanghe Bridge and the existing computational theory of oblique slab bridge，the glide force along cross direction and unbalance moment were found as the damage's cause．Then,several suggestions are presented for future's design and construction.

Key words: oblique slab, ghde, rotation with in surface, blunt angle region, acute angle region

摘要： 现役斜交板桥的损伤状况表明，大多数简易支座斜交板桥存在缓慢下滑及平面内的转动现象．基于塘河大桥 的破坏特征，根据现有斜交板桥计算理论，找出造成其下滑和转动的原因是横向下滑力及平面内不平衡力矩，并据 此提出今后进行斜交板桥设计和施工的几点建议．

关键词: 斜交板, 下滑, 平面内转动, 钝角区, 锐角区