预应力混凝土箱梁锚下局部应力分析

在结构构件的端部和其他布置锚具的地方,巨大的预压力将通过锚具及其下面积不大的垫板传递给混凝土。从而造成锚具下的混凝土将承受着很大的局部应力,因此有必要对锚具下的混凝土进行局部承压强度和抗裂性计算。该文通过对珠江特大桥张拉预应力过程中局部应力变化的模拟分析与现场测试,验证其是否满足局部承载能力要求,以及探讨如何建立合理的有限元模型来对结构进行局部仿真分析。

Analysis of Partial Stress under Anchorage of Prestressed Concrete Box Beam

At the end of structural member and in the other places where anchorages are arranged large pre-compressed force will be transferred to concrete by anchorage and sole plates with not large area under the anchorage so as to cause that the concrete under the anchorage will bear very large partial stress, therefore, it is necessary to calculate the partial bearing strength and crack resistance of concrete under anchorage. The paper tests and verifies whether it meets the requirement of the partial bearing capacity through the simulate analysis of the partial stress change and the testing in the site in the course of stretching the prestressed force of Zhujiang Extra Large Bridge. The paper also approaches how to establish the reasonable finite element model is in order to make the partial imitation analysis of the structure.