Research And Optimization Of The Relationship Between Project Duration And Cost Under EPC Mode Led By Design Institute

The traditional project management mode can’t meet the increasing demand of project construction and management,and the design institute with single business needs to find a new way out in the wave of integrated new ideas.In such a trend,the EPC management mode led by the design institute emerges at the historic moment,which is favored by the advantages of wide service coverage,high comprehensive benefits and reasonable resource allocation,and it doesn’t violate capital construction procedures.Project duration and cost are the two key objectives of project management,and the control of the two is in a state of relative balance.Under the EPC management mode led by the design institute,concurrent partially design and construction can help shorten the construction cycle,but also lead to the increase of extra costs.It is impossible to reduce both of them at the same time,so a relative balance can only be achieved within a certain range to ensure project benefits.At present,the research on project duration and cost is limited to the construction stage,and the global optimization are not considered from the two stages of design and construction.It is necessary to further explore the quantification and trade-off of the relationship between project duration and cost in the concurrent stage,to ensure the relative balance between the two in the whole process of project construction,to achieve the maximum of the comprehensive benefit of the project.First of all,the necessity,feasibility,as well as the existing advantages and disadvantages about the EPC management mode under the design institute led by are analyzed and determined,from the construction market environment,the adjustment about design institute business model,inter-enterprise cooperation and level of contractor project management and other aspects.Secondly,based on the theory of concurrent engineering,the organization structure and process management mechanism of this model were reorganized and optimized,and we establish Integrated Project Alliance to take charge of the operation and decision about this project.On the other hand,IDEF0 method was used to optimize the management and control of the EPC project process.Thirdly,the paper analyzes the impact of concurrent partially design and construction on project duration and cost from the global perspective.And the model of rework workload and the model of excess cost input are established based on concurrent engineering theory and crash strategy to quantifies the relationship between project duration and cost in the process of concurrent partially design and construction and analyzes the optimal starting time in the construction stage.Finally,The model of excess cost input is applied to the actual case for analysis and verification,and the concave curve of excess cost input on starting time of construction stage is determined,which proves the feasibility of model.And the relationship are analyzed by Parameter constraint estimation of partial linear variable coefficient model,which concluds dependence between design and construction,difficulty of rework,the crash strength and the optimal starting time were positively correlated,but fines are negative correlation.For super-high and complex large projects may need several unit cooperation,should guarantee the drawings of the maturity and a consortium of cooperation tacit understanding,downstream of the early start time to ensure that the benefit maximization.So as to provide quantitative decision basis for enterprise and project managers.