Tangshan Urban Underground Pipe Gallery One Phase Of The Foundation Pit Supporting Research And Analysis

The current with the constantly emerging of the high-rise building and underground space project,deep foundation pit support is an indispensable part of construction engineering.In the urban center area,the surrounding area is often accompanied by adjacent buildings,structures and various underground pipelines.The surrounding conditions of foundation pit support are becoming more and more complicated,the problem of deep foundation pit engineering is becoming more and more.For the actual situation,how to choose the economy,reasonable support system,the proper construction method and process become the key of foundation pit support project.This paper mainly focuses on the foundation pit of the underground tunnel of Tangshan city.The project is located in the center of Tangshan city,Adjacent to buildings and structures,underground complex pipelines are densely distributed,adverse factors such as poor construction conditions.For the characteristics of this project,detailed understanding of the engineering geology and hydrogeology of the first phase of the underground complex in Tangshan city,the stability factors affecting the surrounding structure of deep foundation pit are analyzed.Such as foundation pit depth,distribution of underground soil layer,groundwater depth and type,ground load,construction season and so on.The foundation pit support is designed.The corresponding construction method is selected.And the foundation pit monitoring scheme is prepared.The main content includes the following aspects:(1)Reference is given to the information and literature about deep foundation pit support,the present situation and development trend of deep foundation pit are reviewed.(2)The theoretical calculation formula of foundation pit support design is expounded.The common types and scope of deep foundation pit support are summarized.(3)Design of foundation pit support for the proposed project,choose the foundation pit support system supported by the slope pile.The structure of foundation pit supporting structure is analyzed by using the finite element software of the deep foundation pit,theoretical study on stability of foundation pit support system is carried out.(4)The deformation data of foundation pit measured on site are compared with those calculated by finite element analysis,it is found that the measured deformation of foundation pit is less than theoretical calculated deformation.Prove that the foundation pit support design is in line with the actual field,the plan is workable.