大跨度斜拉桥钢锚箱锚固区试验与计算分析

以某大跨度斜拉桥钢锚箱式索梁锚固结构为研究对象,通过比选确定正确的计算单元组合和合理的计算梁段长度,此外全面分析构造细节如风嘴等对锚固区应力分布的影响程度,从而建立索梁锚固区局部结构的空间非线性仿真计算模型。选择该桥最不利的索梁锚固段进行静载模型试验,其中钢锚箱结构采用足尺试件模型,在保证模拟边界条件的真实、有效性的基础上对主梁结构都进行了适当的简化。通过数值分析和静载试验研究的对比验证,表明本文所提出的有限元数值模拟是合理的,并具有较好精度;采用空间有限元分析和足尺模型试验相结合的方法是研究索梁锚固区应力分布的有效手段。

Model Test and Calculating Analysis of Steel-anchor-box Anchorage Zone for Long-Span Cable-Stayed Bridge

A steel anchor box in cable-girder anchorage zone of a long-span cable-stayed bridge has been studied.Correct element combination and rational length of the cable-girder anchorage zone have been confirmed though analyses.Influence of the structural details,such as the fairing has been considered too.A 3-dimensional nonlinear analysis model of the steel anchor box in the cable-girder anchorage zone was thus established.And the worst zone of the long-span cable-stayed bridge was selected as the test object under static load.A full-scale steel-anchor-box model was used in the test.The main girder model was simplified on the basis that the simulation boundary is rational and efficient.Comparison to the data of finite-element analysis to the test result shows that the proposed finite-element analysis is logical and precise.Combination the finite-element analysis with model test is an effective method to study cable-girder anchorage zone.