预应力锚索围护桩支护方案可行性有限元分析

FEA on Feasibility of the Supporting by Enclosing Piles with Pre-stressed Anchor

在岩土及地下结构工程中 ,预应力锚索、围护桩等地下结构在一定的受力条件下既可能与其相互接触的土体产生开裂又可能产生错动滑移现象。为了较真实地反映接触面间的这种受力特性 ,通过引入一种可以模拟开裂和错动滑移现象的接触面单元 ,对预应力锚索和围护桩与土体间的相互作用进行模拟 ,提出了预应力锚索施工过程的简化模拟方法 ,并运用同济曙光岩土及地下工程设计与分析软件对某基坑预应力锚索围护桩支护方案进行了基坑动态施工全过程模拟 ,计算得到了该基坑施工过程地表位移、临近建筑物基底沉降、围护桩位移、受力和预应力锚索轴力 。

In geotechnical and underground structural engineering, under some loading conditions the soil body in contact with the prestressed anchor and enclosing piles may be cracked or slip. In order to express such loading character of the contact area, the contact area element capable to simulate the cracking and slipping is introduced in this paper and the interaction between prestressed anchor and enclosing piles with the soil body was simulated. A simplified method to simulate the operation process for prestressed anchor is suggested. For the supporting scheme of certain foundation pit by prestressed anchor and enclosing piles, the dynamic construction process of the pit is simulated with Tongji Shuangguang Design and Analysis software for geotechnical and underground engineering. The ground surface displacement, settlement of foundation base of the building nearby, displacement and loading of enclosing piles, axial force of pre stressed anchor have been obtained. Based on the results obtained, the feasibility of the supporting scheme was analyzed.