Surface subsidence features of pit in pit foundation and application of stratum compensation theory in sand cobble stratum
SUN Yi
ZHANG Dingli
ZHAO Yong
Abstract："Pit in pit" is a common excavation problem,and its excavation form and different locations increase the complexity of stress and displacement field of surrounding stratums,bringing about a certain difficulty for design and construction.Based on the typical sandy cobble stratum of Beijing,deformation features of pit in pit foundation are analyzed by applying the numerical model,and three factors are compared with ground deformation,which aredistance,depth and widthof inner pit edge.Meanwhile,the adaptability of stratum compensation method in sand cobble stratum in Beijing is discussed,and suggestions for similar engineering in other fields in terms of the estimation of depth of wall lateral displacement are also provided.The results show that shape of soil mass between inner pit and outer pit mainly causes the different surface deformations of both sides.Stratum compensation methodis applicable for describing the relation ship between the ground surface deformation of pit in pit foundation and wall lateral displacement.The research achievements can provide references for monitoring measurement of pit in pit foundation and construction fine control under sand cobble stratum in Beijing and other similar areas.
Keywords：pit in pit foundationsurface subsidencewall lateral displacementstratum compensation theorysand cobble stratum
Publication Date：2018-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：11( 7-17 )