Research On Risk Management Of TBM Construction Progress Of Metro Tunnels

As a kind of urban public transportation,subway is more and more favored by people due to its advantages such as fast,safe,comfortable,large volume,and environmental protection,and it has gradually become the preferred way for people to travel in the 21 st century.As an important part of the entire subway project,the subway tunnel is vital to the construction of the entire subway project.However,the subway tunnel has a long construction period,a lot of resources,and staff to participate in the construction.The construction process often faces complex and changeable hydrogeological conditions and the surrounding environment.It is often accompanied by difficult construction and technical complexity.Risk factors will affect the realization of the economic and social benefits of the metro project on time.therefore it is very necessary to carry out management research on the risk of subway tunnel construction progress.Compared with developed countries,the research on TBM construction schedule risk management of subway tunnels in China is still in the exploratory stage,the theoretical and practical guidance of TBM construction schedule management of subway tunnels has not yet been formed.Based on the TBM construction process of the subway tunnel,this article is based on the TBM construction process of subway tunnels,starting from the theory of schedule wind management,based on the perspective of the contractor.This paper makes a detailed study on the theory and practice of TBM construction schedule risk management of metro tunnel.First,it introduced the theory of project risk management and project schedule risk management and analyzed the characteristics of TBM construction of subway tunnels and the construction process which lays a theoretical foundation for subsequent research.Then,by reading the existing literature about the research results of risk management in the field of metro tunnel engineering,referring to the relevant standards and specifications of metro engineering,and combining the methods of risk identification such as expert interviews,66 risk factors affecting the construction progress of metro tunnel TBM are preliminarily obtained.Then,the risk factors are summed up from six levels,such as people,construction equipment,construction materials,construction and installation,environment,organization and management,to form the initial index of risk assessment.Then,the influence degree of the initial risk factors that affect the construction progress of metro tunnel is scored through questionnaire survey,and the risk factors are screened and reorganized through factor analysis.finally,the risk evaluation index system of the construction progress of metro tunnel TBM is constructed,which is composed of six first level indexes and 29 second level indexes.Secondly,comparing and analyzing the advantages and disadvantages of commonly used weight calculation methods and evaluation methods.at the same time,considering the characteristics of expert evaluation information with ambiguity and uncertainty,calculations based on "expert consulting method" and "triangular fuzzy number hierarchy analysis method" are proposed.The index weights of the TBM construction progress risk assessment system for subway tunnels;then,based on the grey ambiguity of the TBM construction progress risk assessment system for subway tunnels,the grey system theory is introduced to construct a grey cluster of subway tunnel TBM construction progress risks based on the central point triangle whitening weight function Class evaluation model.Finally,taking the tunnel project from Taidong Station to Haiboqiao Station of Qingdao Metro Line 1 as an example,combined with the actual collected data,and evaluated by a gray cluster evaluation model,by calculating the overall clustering index of the overall evaluation index.It was obtained that the risk level of the construction progress of the tunnel project from Taidong Station to Haiboqiao Station is at a relatively high level.The evaluation results are consistent with the actual construction progress,which verifies the accuracy and practicability of the model.In addition,according to the results of the risk assessment,some feasible measures and suggestions are proposed for some key risk factors in the project,which can provide a certain reference for the progress risk management of similar subway tunnel projects.