|The Laws of Differential Settlement in Top-Down Construction Method of Deep Foundation Pit Analyzed with Numerical Simulation
|中文关键词: 差异沉降 逆作法 深基坑 有限元分析
|英文关键词: Differential settlement Top-Down method deep foundation pit simulation analysis
| 地连墙和柱作为最重要的基坑支护结构，在深基坑开挖施工过程中，地连墙与柱的差异沉降将直接影响到整个深基坑的安全。本文采用MIDAS/GTS有限元分析软件模拟分析了基坑的整个逆作法开挖过程，分析了地连墙与立柱的沉降规律。研究表明：地连墙与柱之间的最大差异沉降大于相邻柱之间的沉降，地连墙与柱之间最大沉降差异值为4.09 mm，小于规范20 mm以及1/400柱距；随着开挖的进行地连墙与柱是先隆起再沉降。计算结果对基坑施工中地连墙与立柱的沉降控制提供了宝贵的依据，有助于提高整个基坑施工的安全。
| The diaphragm wall and upright column are considered as the most important supporting structures of foundation pit, and the safety of deep foundation pit was directly influenced by the different settlement among diaphragm wall and upright column during the pit excavation. Finite element software MIDAS/GTS has been applied to conduct a simulation analysis of the pit excavation with Top-Down method and to research the settlement laws of diaphragm wall and upright column. Analysis shows that the maximum differential settlement between diaphragm wall and upright column has been larger than the one between columns. The maximum differential settlement was 4.09mm, which is smaller than 20mm or 1/400 column spacing in the code, and the diaphragm wall and columns are first uplift and then settled as the excavation proceeds. The results provides a valuable basis for the control of settlement of the diaphragm wall and upright column and can help to improve the security in the construction of foundation pit.