| In recent years,with the rapid development of China’s economy,people’s living standard has been improved by leaps,followed by the plight is a serious problem of urban congestion.Rapid pace of life and congestion of the traffic situation have become the key problems to be solved in the city.In order to solve this problem,more and more cities begin to develop urban rail transit system to alleviate the serious problem.Since the 90 s of last century,China’s urban rail transit began a rapid development.China has become the world’s largest urban rail transit construction,and the construction of the city’s largest country.Therefore,the construction safety of the depot and cover property has become a hot spot in the subway construction.How to ensure the safety of the subway construction,especially the control of the construction of the depot and its cover property,has become a problem that cannot be ignored in the construction of the subway.In this paper,taking the dynamic impact process of the foundation deformation settlement which caused by the construction of the main section of depot and its cover property of a coastal city Metro Line 3 as the research object,and using finite difference program FLAC3 D for the numerical simulation of the main section of the depot and its cover property construction,the subsidence and deformation characteristics of lead in the construction process of formation were studied as well.For the deformation phenomenon in the process of subway construction,the paper put forward the deformation monitoring and early warning methods of the subway construction foundation based on the BP neural network.The main contents of this paper are as follows:First,this paper introduces the research status of the typical environmental impact and safety of subway depot construction at home and abroad,especially from the following five aspects: the research status of subway depot construction,the research status of typical environmental impact factors,the research status of the section safety analysis,the research status of the subway depot construction on the typical environmental impact and the main research methods of the strata deformation caused by the subway construction.Second,the basic theory of strata deformation in subway construction is introduced,which is mainly from the following three aspects: soil constitutive relation and consolidation settlement theory,surface subsidence law and numerical simulation theory.Third,changes in the displacement of the soil transfer to the building(structure),will change the role of the building(structure)soil and water pressure,the size of the ground reaction and distribution,forcing the building response,such as local longitudinal vertical and horizontal displacement or cause the building(structure)deformation of the building.The deformation of the building(structure)caused a certain degree of damage to the structure and function of the building.In this paper,the construction simulation of the depot and the cover property of the subway line 3 in Shenzhen are carried out.The finite element differential simulation software FLAC3 D is used to simulate the construction,and the deformation of the strata caused by the building construction is analyzed and studied based on the energy transfer theory.Forth,the construction of the subway depot and its cover property has a wide range of risks for itself and the surrounding environment,and the risk is extremely high.In the context of a large-scale subway construction in a coastal urban area,there is an urgent need to study the construction safety problems of the subway facilities and the construction of the cap.This project intends to select the influence of the construction of the depot of Shenzhen Metro Line 3 as the research object,and systematically study the displacement of the foundation caused by the construction of the depot Shenzhen Metro Line 3,so as to provide a reliable basis when optimize the construction plan and put forward Safety control measures.Fifth,taking the FLAC3 D simulation model of the dynamic construction of the cover property,the detailed analysis of the deformation displacement of the roof strata of the construction section of the construction project is carried out in detail.The engineering survey data is from the field investigation and construction area.At the same time,the engineering analogy method is used to analyze the parameter safety of the strata deformation value,forecast the safety and reliability of the construction of the cap property,and put forward the safety precaution measure.Sixth,this paper introduced the basic theory of BP neural network model,and put forward the method of deformation monitoring based on BP neural network.Then established the analysis model based on BP neural network module,as well as forecasted and predicted the actual monitoring data.The main innovations of this paper:First,the vehicle model maintenance workshop is chosen as the representative structure of the building,and the dynamic model of the foundation and the foundation beam structure is carried out,and then the deformation displacement and the risk prediction are innovated.Second,through the simulation of the cover property-construction,the deformation displacement and the risk prediction of the roof strata caused by the construction of each step are innovative.Third,a method of deformation monitoring and early warning of subway construction foundation based on BP neural network is proposed. |
