钢支撑预加轴力调整对围护墙剪力与变形的影响

Effect of Steel Bracing Pre-axial Force on Shear Force and Deformation of Enclosure Wall

基于温州市域铁路老殿后河段深基坑工程,采用数值模拟的方法,对施加钢支撑预加轴力对围护墙剪力与变形的影响作出了研究。结果表明:竖直方向上,1道钢支撑预加轴力增大必然导致该处围护墙剪力增大,围护墙的最大水平位移减小,其中浅层钢支撑预加轴力调整对围护墙剪力与变形的影响大于深层钢支撑,越早增大预加轴力对围护墙的变形控制效果就越好;对浅层钢支撑施加较大的预加轴力可以弥补因开挖和深层钢支撑安装造成的预应力损失。所得结论也可为基坑支护结构设计和施工提供理论依据和参考。

Based on the deep foundation pit engineering of Laodianhou River of Wenzhou Railway,the effect of preaxial force of steel bracing on shear force and deformation of enclosure wall is studied by numerical simulation.The results show that pre-axial force increase of steel support inevitably causes the shear force to increase and the maximum horizontal displacement of the enclosure wall reduce in vertical direction.The effect of pre-axial force adjusting of steel bracing in shallow layer on shear force and deformation of the enclosure wall is greater than that in deep layer.The sooner increasing the pre-axial force,the better the deformation control of enclosure wall;The prestress loss caused by excavation and installation of steel bracing in deep layer can be compensated by applying larger preaxial force of steel bracing in shallow layer.The conclusion provides theoretical basis and reference for the design and construction of foundation pit supporting structure.