Key Technical Research On The Construction Of Super-deep Foundation Pits With The Complex Geological Conditions

With the rapid development of the construction industry in our country,large and medium-sized cities have seen a large number of supertall buildings.Supertall buildings are built in urban areas and most of them are landmarks,it is inevitable that the excavation of the excavation will cause many difficulties.First of all,the tall building is mostly landmarks is very strict to the time limit for a project,under the condition of uncertainty factors not rule out to try to speed up the construction progress to ensure timely completion of construction tasks;Secondly,the ultra-high base pit depth is deep and the construction site is smaller and the surrounding population is dense,unable to adopt the method of slope construction;Thirdly,the construction area of the supertall foundation pit is close to the commercial area and residential area.The requirements of subsidence on the ground surface of the foundation pit are very high in construction.Finally,supertall buildings are usually adjacent to roads,with large traffic and the dynamic load of the vehicle has an important effect on the underground municipal pipeline surrounding the foundation pit.This paper discusses the construction difficulties of the above construction of the civil rights gate of the civil rights gate of subway no.6 in tianjin,tianjin.The details are as follows:1、In view of the strict time limit for a project and construction site more restricted problem,according to the field of construction experience and the actual situation of innovation adopted ring plate of the inverse-center island suitable to do construc;2、Based on the problem of subsidence of ground subsidence in the foundation pit,the surface subsidence simulation and excavation monitoring technique of foundation pit are adopted.Through numerical simulation and monitoring data collect mastered the excavation process of underground continuous wall and the change of the surrounding ground settlement,can be found hazards and respond in a timely manner;3、In view of the influence of the vehicle load on the municipal pipeline around the foundation pit,the underground pipeline protection technique was adopted.The post-grouting can protect the underground pipeline;In this paper,the research to ensure the safety of deep foundation pit construction has the special significance,and to the excavation construction of the similar project in tianjin region and surrounding buildings protection is of practical reference value.