预应力空心板在我国公路桥梁中有广泛应用,本文通过30m跨径实桥空心板的反复加载试验发现纵向裂缝一般首先出现在构件有缺陷的部位,试验数据表明在荷载和裂缝宽度较小的裂缝开展初期,纵向裂缝宽度发展受循环加载荷载及次数的影响不明显;而当荷载和裂缝宽度增大到一定程度时,纵向裂缝宽度随荷载水平的增加而明显增加。研究结论对于掌握空心板桥梁在反复荷载作用下的纵向裂缝开裂行为及其损伤累积规律、对于认识桥梁性能变化过程有重要参考意义。 Prestressed hollow slabs are widely used in highway bridges in our country. In this paper, the longitudinal cracks are generally found in the defective parts of the slab at the first time through repeated loading tests on the hollow slab with 30m span. The experimental data show that in the case of small load and crack width In the initial period of crack initiation, the development of longitudinal crack width was not affected obviously by the cyclic loading load and the number of times. When the load and crack width increased to a certain extent, the longitudinal crack width increased obviously with the increase of load level. The conclusions of the study are of important reference for understanding the longitudinal crack initiation behavior and damage accumulation of hollow slab bridges under repeated loading.