悬索桥锚碇结构2D有限元数值模拟与分析  

2D-Finite Element Numerical Modelling and Analysis of an Anchorage of Suspension Bridge

作　　者：李文胜 赖允瑾[2,3] 吴昌将[2,3] 

机构地区：[1]赣州赣康高速公路有限责任公司,江西赣州341000 [2]同济大学岩土及地下工程教育部重点实验室,上海200092 [3]同济大学地下建筑与工程系,上海200092

出　　处：《地下空间与工程学报》2009年第A02期1768-1775,共8页Chinese Journal of Underground Space and Engineering

基　　金：江西省交通厅资助项目(082139)

摘　　要：悬索桥锚碇是平衡悬索桥主缆力的重要构件。锚碇必须具有足够的抗滑稳定性和抗倾覆稳定性,即在主缆力作用下,锚碇的水平位移和垂直位移必须控制在允许的范围内。江西赣州赣江大桥为主跨408米的地锚式悬索桥,其锚碇座落在弱风化粉砂质泥岩层面,这种岩层属于软岩,在饱和状态下强度下降极快。为此,为了满足不同控制水位下大桥安全,锚碇基础面设计了齿坎结构以增加其稳定性。本文采用大型有限元Marc程序对西锚碇基础和地基进行了二维有限元数值模拟分析,得到了锚碇在运营阶段荷载作用下周围介质的水平位移和竖向位移分布规律,以及锚碇基础底部应力分布规律、齿坎接触面的应力分布规律以及周围地层的塑性区发展趋势。计算表明,齿坎对于减少锚碇水平位移和提高锚碇安全度上是有很大帮助的。Anchorage is one of the most important components to balance the cable load of suspension bridge, and shall be designed with enough safety against sliding and overtuming. That ＇ s to say, the horizontal and vertical displacement shall be lower than allowable. Ganzhou Ganjiang Bridge of Jiangxi province is a suspension bridge with a main span of 408m, and has two gravity anchor blocks on each bank. The two anchor blocks are all located on the weak - weathered silty mudstone bedrock which is classified as soft rock with sharply dropped strength in saturation. Therefore , a bench - shape surface structure is designed for the anchor block bottom to improve its safety at utmost water level. This paper presents restdts of 2d - finite element numerical analysis of west anchor block using Mare soft- ware package. These restths include the distribution of horizontal and vertical displacement of surrounding bedrock of anchorage under traffic operation, stress distribution of anchorage bottom and bench - shape surface of bedrock, as well as the development of plastic zone of surrounding bedrock of anchor. The results show that adoption of bench - shape surface is of great benefit to decrease the displacement and improve the safety of anchorage.

关 键 词：悬索桥 地锚式锚碇 齿坎 2D-有限元 数值模拟 

分 类 号：U443.24[建筑科学—桥梁与隧道工程]