摘要
悬索桥桥基边坡由锚碇和桥墩构成复杂的的结构体系,其变形特点与天然边坡有很大区别。为深入研究水位下降对桥基边坡稳定性的影响,以某拟建悬索桥桥基边坡为例,采用有限元强度折减法计算了锚碇与桥墩耦合作用下水位下降不同高度边坡的位移、塑性点和安全系数变化规律。结果表明:随着河道水位逐渐下降,边坡发生主要水平位移的部位也随之下移,锚碇附近岩体位移受降水前期影响大;坡体内部塑性点主要分布在锚碇附近,分布范围随水位降低先增加后减少并最终趋于稳定;边坡安全系数随水位的下降先减小后增加,水位下降40 m后安全系数稳定在1.28;通过分析桥基边坡潜在滑裂面,确定了锚碇受拉是桥基边坡稳定性大小的控制性因素。计算成果可为大桥修建过程中边坡的稳定性评估提供参考。
Suspension bridge foundation slope is a complex structure system with anchor and pier,the deformation characteristics are very different from the natural slope. For further study of the stability of the bridge foundation slope under drawdown condition,a proposed suspension bridge foundation slope is simulated by finite element strength reduction method to analyze the slope displacement,plastic zones and safety coefficient when the anchorage and pier coupling. The results show that with the water level decreasing gradually,the position of main horizontal displacement section of slope is also decreased,and the displacement over anchorage is affected by early drawdown seriously; the plastic points mainly of slope is distributed in the vicinity of the anchorage,ranges increasing firstly and then decrease and finally tends to be stable along with the drawdown; the slope safety coefficient decreases firstly and then increases,stable at 1. 28 after the level decreases 40m; and anchor tension is the key factor of the bridge foundation slope stability by analysis of potential slipping surface. The conclusions can provide some reference for the stability evaluation of the slope during the bridge construction.
出处
《灾害学》
CSCD
2016年第4期134-138,共5页
Journal of Catastrophology
基金
国家科技支撑计划(2014BAL05B01)
西华大学流体及动力机械教育部重点实验室(重点研究基地)开放课题(szjj2015-039)
西部之光青年学者计划A类
中国科学院科技服务网络计划(STS计划)(KFJ-EW-STS-094)
关键词
悬索桥
水位下降
锚碇
位移
安全系数
suspension bridge
drawdown
anchorage
displacement
safety factor
