影响基坑变形的实质性状态变量分析

ANALYSIS OF SUBSTANTIAL STATE VARAIABLES INFLUENCING DEFORMATION OF FOUNDATION PIT

深基坑变形控制设计中 ,要考虑影响基坑变形的因素非常多 ,各因素又很复杂。用非线性数值分析方法进行基坑变形分析的工作量相当大 ,时间很长。为了快速准确地分析基坑变形的规律 ,必须筛选出主要的因素。为此视基坑数值分析范围为一个系统 ,基坑周边沉降、支护结构位移和坑底隆起为系统输出量 ,降水、开挖和支护施工各工况中变化的因素为系统输入量。通过多个基坑实测沉降、位移、隆起量时序数据的关联维数和实质性状态变量个数即基坑变形主要影响因素个数计算 ,结果其个数大为减少 ,极大地减少了数值分析的工作量 ,对指导变形控制设计和施工具有重要的理论和实践意义。

In deformation control design of deep foundation pit, many complicated factors influencing foundation pit deformation need to be considered. Analyzing these factors with nonlinear numerical method need long time. To rapidly and accurately analyze deformation law of foundation pit, the number of main factors must be determined. Regarding foundation-pit scope of numerical analysis as a system; settlement of foundation-pit boundary, displacement of retaining structure and swell of foundation-pit bottom as output of the system; factors during construction of draining water, earth excavation and retaining structure as input of the system. Relevant dimension and the number of substantial state variables which are main factors influencing foundation-pit deformation, are calculated with measured time-sequence data of the settlement, the displacement of several foundation-pits, the number of substantial state variables is far less than that of the factors influencing foundation-pit deformation, the work of nonlinear numerical analyses is greatly reduced, it is of important theoretical and practical significance in guiding design and construction of deformation control.