Research On Influencing Factors And Control Measures Of Expressway Construction Cost Overrun In Fujian Province

With the rapid development of economy and the deepening of urbanization,the expressway in China has become one of the essential transportation infrastructures for social and economic development and production and life because of its great convenience.The number and scale of expressways in Fujian Province are constantly expanding,coming with the large scale of construction funds.The expressway in Fujian Province is mostly mountainous.Its characteristics of complex terrain and geological conditions,high proportion of bridge and tunnel structures in the total length of the route lead to the phenomenon that the construction cost of expressway engineering is out of control.In order to reduce the risk of expressway construction cost overruns,it is necessary to identify and analyze the influencing factors of expressway construction cost overruns in Fujian Province and take effective cost control measures.Firstly,through literature research and questionnaire survey,facing the different construction subjects of expressway projects,the influencing factors of expressway construction cost overrun in Fujian Province are collected,and the preliminary index set of influencing factors of expressway construction cost overrun in Fujian Province is constructed.Secondly,DEMATEL-ISM method is formed by coupling Decision-making Trial and Evaluation Laboratory(DEMATEL)and Interpretive Structural Modeling Method(ISM).This paper uses DEMATEL-ISM method to identify the key factors of expressway construction cost overruns in Fujian Province,and constructs a hierarchical structure model and determines the system boundary.Thirdly,by means of System Dynamics(SD)method,the construction cost control model of expressway in Fujian Province is established,and the relationship among the factors is analyzed.The single-factor and multi-factor simulation of the identified influencing factors is carried out to analyze the degree and effect of the influence on the cost overrun of expressway construction in Fujian Province.Finally,based on the results of the analysis,the paper puts forward some suggestions and countermeasures for the construction cost control of Fujian Province expressway from different stakeholders.The hierarchical structure model based on DEMATEL-ISM method shows that the factors with the most node degree are construction design scheme,design change,bidding competitive price,material control,inferior subcontractors and suppliers,unpredictable site conditions,and professional quality of contractor management personnel,which need to be paid more attention to.SD method combined with the actual engineering case simulation analysis,the study shows the six key factors that lead to the Fujian Province highway project construction cost overrun,including the contractor management level,bidding competition price,land acquisition and relocation time,bridge-tunnel ratio,design change frequency and contractor coordination,multi-factor analysis shows that the contractor has the biggest impact on the Fujian Province highway construction cost overrun.In this paper,DEMATEL-ISM method is proposed by coupling DEMATEL and ISM,and SD simulation model is constructed,which can reflect the dynamic change process of key factors of expressway construction cost overrun in Fujian Province and verify the effectiveness of this method to some extent.The research conclusion can provide reference for the construction cost control of expressway project.