Research On Influencing Factors Of Construction Cost Management Of Metro General Contracting Project

China’s national economy continues to develop rapidly,urbanization and urbanization process accelerate significantly,the scale of urban rail transit construction and operation is growing rapidly,and the number of new rail transit cities is increasing.As a tool to solve urban public transportation,the subway has the characteristics of strong transportation capacity,fast speed,high punctuality rate and convenient ride,which can optimize urban layout and alleviate traffic congestion,which is of great significance for improving residents’ living standards and promoting economic and social development.With the increasing advantages of the EPC model,subway construction projects have gradually transformed into general contracting,which has prompted metro general contracting enterprises to seek more effective cost control methods to obtain higher economic returns to ensure the sustainable development of enterprises.For the general contractor,it is necessary to pay attention to whether the subway construction project can generate benefits,and the project cost management will directly affect the realization of the expected economic benefits.Based on this,this paper deeply explores the influencing factors of cost management of metro EPC projects,analyzes their influencing relationship and internal mechanism,and is conducive to the control of subway construction costs by metro EPC general contractors.Firstly,the relevant concepts and cost management related theories of metro EPC projects are analyzed,the concepts related to metro EPC projects and cost management are fully understood,and the content and control process of metro project cost management are sorted out.Secondly,according to the existing literature research,metro EPC cases and expert interview corrections,the influencing factors of construction cost management of 34 metro EPC projects were preliminarily identified,and the factors with low importance were screened out by questionnaire survey method,and the final influencing list containing 27 factors was determined for further research.Thirdly,the Social Network Analysis(SNA)model and Interpretative Structural Modeling Method(ISM)for the evaluation of the influencing factors of construction cost management of metro general contracting projects are constructed.Finally,based on the identified influencing factors and the constructed evaluation model,the two-station and twointerval project of the EPC project of GZ Metro Line 18 is selected as a case study,and the social network analysis method is used to analyze the relationship between the influencing factors from the two dimensions of the overall network and the individual network,and the five indicators of network density,block model,degree centrality,intermediate centrality and intermediary are selected to measure the close relationship between the influencing factors,quantify the influence and conductivity of the influencing factors,and excavate 10 key influencing factors.ISM is used to construct a hierarchical structure model of key influencing factors of construction cost management of metro EPC projects,analyze the hierarchical structure of each influencing factor,and put forward relevant countermeasures and suggestions for the factors that play an important influencing role.The results show that the key influencing factors of cost management of metro EPC projects include project planning and cost pre-control,EPC general contractor management level,subway EPC construction drawing design level,subway engineering construction organization design optimization,owner’s intervention degree and requirements,climate,geology and hydrological conditions along the metro line,project organization structure and cost control system,project information management,application of new technologies and new processes,traffic facilitation and pipeline relocation along the metro line.The key influencing factors are located in the middle layer of the structure,which is not only constrained by the lower factors,but also affects the upper factors.The lower influencing factors can affect the top-level factors through the accumulation of influence transmission,which in turn affects the economic benefits of the project.