期刊名称：IOP Conference Series: Earth and Environmental Science
印刷版ISSN：1755-1307
电子版ISSN：1755-1315
出版年度：2020
卷号：570
期号：2
DOI：10.1088/1755-1315/570/2/022052
语种：English
出版社：IOP Publishing
摘要：Pit-in-pit is common in foundation pit-engineering practice. Pit-in-pit excavation disturbs the stress field in the passive zone of the foundation pit, which induces the loss of soil resistance in the passive zone and adversely affects the safety of the foundation pit. Based on a real foundation pit supported by diaphragm wall in Hohhot, this study used the finite difference software FLAC3D to establish a finite difference model of the foundation pit. At different construction steps and excavation parameters, the horizontal displacements of the diaphragm wall, the vertical displacement of the soil around the foundation pit, and the plastic zone of the model were analyzed. It was found that the excavation of the inner pit intuitively impacted the deformation of the diaphragm wall, and the asymmetry of the position of the inner pit led to the whole pit's deformation in a certain direction. Furthermore, we reported that the increase in excavation parameters h and l increased the subsidence of the soil closer to the inner pit. Moreover, excavation parameters, including L, h, and l, are proportional to the volume of the plastic area. This study provides reference value for designing foundation pits containing pit-in-pit.
