钢箱梁斜拉桥索梁锚固区极限承载力分析

为了掌握索梁锚固区在索力作用下的应力分布和极限承载力，以青岛海湾大桥红岛通航孔斜拉桥为工程背景，应用等效板厚法近似模拟钢锚箱承压板与锚垫板之间的接触非线性问题；采用板壳单元和梁单元建立了索梁锚固结构的有限元模型，对索梁锚固区在最不利荷载组合作用下的受力性能进行了研究；并考虑几何非线性和材料非线性对锚固区及钢箱主梁进行极限承载力分析。结果表明：在最不利荷载组合作用下钢锚箱与主梁腹板的连接区域应力集中，超过了材料的屈服强度；索梁锚固区的极限承载力为设计荷载的3．07倍，有一定的安全储备。在上述分析的基础上，提出了改善索梁锚固区受力性能的构造措施。

Analysis of ultimate bearing capacity on cable-girder anchorage zone of cable-stayed bridge with steel box girder

To know the stress distribution and ultimate bearing capacity of cable-girder anchorage zone under cable forces,taking Hongdao cable-stayed bridge located at Qingdao bay as an example,the equivalent plate thickness method was adopted to simulate the non-leaner contact problem between setting plate and anchorage frame.The finite element model with shell element and beam element was established,the mechanical behavior of anchorage zone under the most unfavorable load was analyzed.Taking geometric non-linearity and material non-linearity into account,the ultimate bearing capacity was analyzed.The results indicate that: the stress concentration appears on the joint zone between anchor housing and webs of girder;the maximal stress is higher than yield stress under the most unfavorable load;the ultimate bearing capacity of anchorage zone attains 3.07 times as much as its designed load.At last,the configuration measures for amending the mechanical behavior of anchorage zone were proposed.16 figs,11 refs.