工程经验表明:任意的围护结构变形形式均可近似利用正向转动、反向转动及挠曲等3种基本变形模式进行拟合,且通过对基坑开挖过程的有限元数值模拟可知,当围护结构发生上述3种基本变形模式时,坑外深层土体沉降存在较为明显的分布规律。利用3种基本变形模式对围护结构的侧移曲线进行拟合,求得所对应的最大位移值,然后根据3种基本模式所对应的坑外深层土体沉降曲线分布,求得每一基本模式所对应的坑外深层土体沉降分量,并进行叠加,从而求得坑外深层任意点的沉降值。 The engineering experience shows that any deformation pattern of the envelope can be approximated by using three basic deformation modes: forward rotation, reverse rotation and deflection. Through the numerical simulation of the excavation process of the foundation pit, When the above three kinds of basic deformation modes occur in the envelope structure, the settlement of deep soil outside the pit has obvious distribution rules. Three kinds of basic deformation modes are used to fit the lateral displacement curve of the envelope and the corresponding maximum displacement value is obtained. Based on the distribution of the settlement curves of the deep soil outside the pit corresponding to the three basic patterns, Model corresponding to deep subsoil settlement component, and superimposed, so as to obtain any point of deep settlement outside the pit value.