高速铁路复杂箱形截面预应力混凝土梁疲劳性能试验研究

Experimental Analysis of Bending Fatigue Behavior of Prestressed Concrete Girders with Complex Box-type Section Used in High-speed Railway

以武广高铁武汉站36 m跨复杂箱形截面预应力混凝土简支梁为原型,制作4个1/6缩尺模型,其中1个模型加入13%的高分子聚合物胶乳,通过静力试验和疲劳试验,考察了复杂箱梁在正常使用和超过设计值的循环荷载作用下的疲劳性能,以及聚合物对箱梁疲劳性能的影响。试验结果表明,根据运营阶段箱梁控制截面底部的最大和最小应力值确定的加载幅值作用下,200万次加载后表明模型的疲劳寿命满足要求,并且对后期高幅值加载下的疲劳性能没有影响,聚合物的加入对模型的疲劳性能没有负面影响。

Based on a prestressed concrete girder with complex box-type section of 36m span,four models of 1/6 scale are made,and one of them is mixed with a kind of polymer latex.Experiments with monotonically and cyclically loading are carried out on the models to study bending fatigue behavior of the girder in service and under cyclic load exceeding the designed value,as well as the impact of polymer on fatigue performance of the girder.The results show that,under the cyclic load of value determined by the maximum and minimum stress at the key part of the girder in service,the fatigue performance is satisfactory and the fatigue behavior under a subsequent larger cyclic load is similar with that one under the same big cyclic load.Besides,the polymer has no negative effect on fatigue behavior of the model.