沈阳东森深基坑工程三维有限元分析

沈阳东森商务广场深基坑工程位置毗邻沈阳市政府和市区主要交通干线,基坑平面形状复杂,开挖深度大。为了进一步研究沈阳地区深基坑开挖对土体变形和应力影响规律,控制基坑侧壁与支护结构变形,采用现场原位测试获得的土体参数,应用有限元软件ADINA建立三维模型,对施工过程进行了动态模拟分析。并对支护结构水平位移进行了现场监测,监测结果与数值模拟结果基本吻合,验证了模型的可行性和模拟结果的可靠性。分析结果表明,基坑侧壁的最大水平位移发生在顶部,坑底隆起值越靠近基坑中心越大,向坑壁方向逐渐减小。锚索轴向应力在锚固段顶点有应力集中现象,反映出锚固段的锚固效果较好。在坑底坡脚位置土体主应力集中,该区域为土体塑性破坏区,建议对该处进行加固处理。

3D finite element analysis of Dongsen deep excavation in Shenyang

A deep excavation of Dongsen central business district is adjacent to Shenyang government building and major traffic lines.Its planform is complicated and the excavation depth is high.For further study on the influence of deep excavation on soil deformation and stress in Shenyang area and for control of the deformation of foundation pit wall and retaining structure,soil parameters were obtained by in-situ tests,3D analysis model was established using finite element software ADINA,and dynamic simulation and 3D finite element analysis are carried out for the entire process of excavation and supporting with the horizontal displacement of the supporting structure monitored.Numerical simulation results are basically consistent with the monitoring results,which verifies the feasibility of the model and the reliability of the simulation results.The results show that the maximum horizontal displacement of the sidewall occurs at the top;that the foundation heave increases towards the center of the foundation pit but decreases gradually towards the sidewall.Axial stress concentration occurs in the anchorage section of anchor cable,which reflects a better anchoring effect.Stress concentration appears at the bottom of the foundation pit,which indicates a plastic zone of soil,and reinforcement treatment is recommended.