抽、灌水作用下上海土层变形特征的探讨

Investigation of the Deformation characteristics of Various Soil Staata under the Influence of Pumping out & back of Ground Water in Shanghai

本文在总结分析以往大量的野外实测资料和室内试验资料的基础上,阐明了地下水位的升降变化是导致上海地面沉降的主要原因。文中论证了第一、二压缩层的流变性质,并指出含水砂层的变形在上海地面沉降中的主要作用。通过对各土层单位变形量的分析,将各土层的实测变形量根据水位变幅予以规格化,以便判断各土层的回升与沉降情况,文中还运用了“胀缩比”的概念,分析了上海各土层的残余变形特征。

Based on analysing a large quantity of data obtained from in-situ observation and laboratory experiments, it is explored that the main causes offthe land subsidence in Shanghai are the cyclic variation of the ground water table. The reological properties of the 1st and 2nd compressible strata are discussed. The important contribution of the compression of the aqueou sand stratum to the land subsidence in Shanghai is mentioned. In calculating the values of storage coefficient of various soil strata, the rule of rebound and settlement can be readily evaluated by norma-li zing the observed deformation of different soil strata according to the range of variation of the ground water table. The conception of the ratio between rebound and compression is used to study the characteristice of residual deformation of various soil strata in Shanghai.