预加轴力动态补偿对基坑变形的影响研究

Study on the influence of compensating dynamically prestress on foundation pit deformation

为探讨动态施加预加轴力的变形控制效果,以厦门市地铁三号线创业桥站基坑工程为研究对象,基于基坑支撑拆除阶段实测数据及有限元分析结果,文章分析了预加轴力动态补偿对基坑形变的影响规律。结果表明:钢支撑的拆除容易导致围护水平结构的侧移量突变,对基坑本身以及周边环境造成不利的影响,支撑进行预加轴力动态补偿能够有效地控制最大水平侧移量;对支撑补偿30%轴力设计值的方案3是最经济高效的,使基坑最大水平侧移量减小了42%。

In order to explore the deformation control effect of compensating dynamically prestress,the foundation pit project of the Chuangyeqiao Station of Xiamen Metro Line 3 is taken as the research object.And the effect of compensating dynamically prestress on foundation pit deformation is analyzed,based on the measured data of support demolished stage and finite element analysis results.The results show that the demolition of steel support can easily lead to the sudden change in lateral displacement of the retaining horizontal structure,which has adverse effects on the foundation pit itself and the surrounding environment.Compensating dynamically prestress of support can effectively control the maximum horizontal lateral displacement.Adopting the scheme 3 whose support has been compensated dynamically of 30%prestress designed is the most economical and efficient,which reduces the maximum lateral displacement of the foundation pit by 42%.