摘要
上海长江大桥斜拉索与索塔锚固采用结构形式新颖的钢锚箱式锚固结构,最大斜拉索索力达到1127t,钢锚箱板件数量多、构造复杂,在强大索力作用下结构的受力性能值得关注。介绍了该索塔中钢锚箱节段模型试验,得到了钢锚箱板件的应力分布,总结了钢锚箱板件间的传力机理。通过有限元数值计算结果与试验结果的对比分析,验证了数值计算方法的准确性。试验结果和数值计算结果表明:钢锚箱在强大索力作用下,板件应力分布复杂,不均匀程度严重,在1倍设计索力作用下钢锚箱处于弹性状态,但有部分位置的应力超过了规范规定的设计强度值,即使在1.7倍设计索力作用下,钢锚箱仍能继续承载,没有出现明显的变形。建议对于钢锚箱这样的结构在不过多降低结构安全储备情况下可以适当利用部分钢材的塑性。
A recently developed steel-anchor-box was adopted in the cable-pylon anchorage zone of the Shanghai Yangtze River Bridge with the largest cable-force of 1127 tons. Due to the complex fabrication and large number of plates being used, a thorough investigation on the mechanical behavior of the steel-anchor-box is required. The experimental and numerical studies are presented in this paper. The stresse distributions in the plates are obtained and the loading transmitting among the plates is determined. Comparing the FEM results with experimental results, the accuracy of the numerical method is verified. The stresse distribution in the plates is non-uniform. Under the normal design cable force, the steel-anchor-box behaves in elastic range, but the stresses at some locations of the plates are larger than the design strength prescribed by the current code. The deformation of the steel-anchor-box is small even trader loads which produce 1.7 times of the design cable force. Hence, it is suggested that partial plasticity be permitted in the steel-anchor-box, as long as the structural safety is not impaired significantly.
出处
《工程力学》
EI
CSCD
北大核心
2008年第10期126-132,共7页
Engineering Mechanics
基金
国家自然科学基金项目(50708075)
国家863计划项目(2007AA11Z105)
关键词
桥梁工程
斜拉桥
试验
索塔
钢锚箱
传力机理
数值分析
bridge engineering
cable-stayed bridge
experiments
cable-pylon
steel-anchor-box
mechanical behavior
numerical analysis
