Deformation Behavior Study On The Enclosure Structure Of Pits In Foundation Pit

In recent decades, a great deal of engineering is under construction and reviews in many cities. With a large scale of underground space development, the building nu- mber and volume of excavation engineering is increasing, and complexity structural type of pits in foundation pit appears. Based on the research of deep excavation and excavation bracing home and abroad, new exploration of deep excavation and excavation bracing which is a traditional topic in rock and soil engineering is explored in this article. Combined with practical projects, this article analyzed and discussed the the ongoing more and more experiments of pits in foundation pit.Guangzhou Haixinsha metro foundation pit engineering is a typical case of deep and large pits in foundation pit, and its scale and depth is rare in the district of China. Combined with Guangzhou Haixinsha metro engineering, the correlative research and analysis is explored in this article. Firstly, in-site experimental study was conducted f- or excavation engineering, and this testing data was summarized. Secondly, non-linear finite element analyze was conducted for pits in foundation pit of Haixinsha metro ex- cavation engineering, and analysis result inosculated the measured data very well. On this basis, the infection of deformation behavior of pits in foundation pit was further analyzed and discussed.This article has completed a few tasks and made several conclusions.They are as the followings:In-site experimental study was conducted for pits in foundation pit in Haixinsha metro excavation engineering.By analyzing accurate records about internal force and distortion of excavated pile and deep distortion of soil mass, mechanic properties of bracing system and infection of surrounding environment are probed when the pits in foundation pit excavated. On the basis of these information, received the change law of bracing system and surrounding soil about pits in foundation pit.Non-linear finite element analysis was conducted for pits in foundation pit of Ha- ixinsha metro excavation engineering.This model regarded the system of the soil, ret- aining pile, steel support as plane, and internal force and distortion of bracing system in every woring condition was calculated. It worked out the isopleth of excavation ve- rtical and horizontal movement. Secondly, it educed the vertical displacement curve of enclosure structure. The illustrative calculating results reveal the distribution rules of earth mass displacement and sedimentation, soil press- ure and major principal stress comprehensively.Finally, basis on finite element model, the comparative analysis was carried out on pits in foundation pit under different over loading, different displacement, different excavation depth, different characteristic of retaining pile and soft soil, change law of pits in foundation pit under changed the parameters was probed through finite element calculation.