Influence Of Tunnel Pile Construction On The Settlement Of Surrounding Buildings And Optimization Of Schemes

With the rapid development of China’s economy,the result is the redistribution of economic resources.The enrichment of various urban resources makes the urban population more dense.There had be 10 cities with a population of more than 10 million and 30 cities with a population of more than 8 millionin in China,especially the super-large metropolises such as population of more than 18 million Bei,Shang,Guang and Shen.Therefore,this requires people to develop a new living space,urban underground space.More and more underground shopping malls,subways and other projects are being built,especially a subway engineering,which plays an irreplaceable role in urban transportation.In areas with dense buildings,heavy traffic or dense pipelines,the construction of underground subway excavation stations is very strict on ground settlement control and building deformation control.The PBA method has its unique advantages in these respects.The PBA method had solved the problems of large-section excavation in loose and weak strata,especially the northern part of China.This paper studies the influence of the excavation sequence of small and medium-sized tunnels on the surface deformation,station structure deformation and building deformation in the PBA method through the Dongba Zhongjie subway station.This paper uses Midas GTSNX to build a 3D model for finite element simulation.specifically The following aspects specifically are mainly studied:1.According to the engineering geological conditions of Dongba Zhongjie Station,a 3D geological model is established in the Midas GTSNX software.We simulate the real construction plan,and obtain the deformation data of the soil,station structure and building points,and compare and analyze with the field measured data.2.According to the simulation results,we can analyze the law of ground settlement,station structure deformation and building deformation of the main four construction stages of small guide tunnel excavation,pile-column system construction,buckle arch construction and station platform excavation.3.The paper simulates the different excavation sequences of the oriented holes,and analyzes the seven schemes formulated,optimize the construction scheme for striving to achieve the minimum impact of the construction process on surface settlement,station structure deformation and building deformation.