Research On Cost Management Of Jacking Frame Bridge Under Existing Railway

The jacking frame bridge under the existing railway has the advantages of good structural integrity,high stiffness,low cost and little impact on the operation of the existing railway,so it is widely used in the horizontal to vertical engineering.In recent years,with the continuous advancement of urbanization,the number of jacking frame bridge projects is gradually increasing,and the construction scale and construction technology level are significantly improved.The jacking frame bridge project involves a wide range of fields,the construction process involves many parties,and the construction cost is complex.Due to the imperfection of the index system of the current estimate and estimate,the concrete cost control measures in the design stage,and the separation of cost management and design process,the construction cost of the jacking frame bridge project increases obviously,and the phenomenon of "Three Excesses" occurs frequently.It seriously hinders the further promotion and application of jacking frame bridge construction.In view of this,combined with the actual project,taking the design stage as the core,this paper makes an in-depth study on the prophase cost management of the jacking frame bridge project,and analyzes the factors influencing the construction cost of the jacking frame bridge based on the cost results of the actual project design stage.The main research contents are as follows:Firstly,this paper analyzes the development and status quo of the current project cost management research,and points out the problems in the process of the jacking frame bridge project cost management.Investment estimation is an important reference for quota design in the design stage.In order to improve the accuracy of investment estimation,based on the characteristics of the cost composition of the jacking frame bridge under the existing railway,an investment estimation method combining fuzzy theory with analytic hierarchy process(AHP)is proposed,and the application steps of fuzzy analytic hierarchy process(FAHP)are summarized,and the bottom element is the sub project of jacking frame bridge project The hierarchical structure model is applied to an example.Secondly,it analyzes the content of cost management in the design stage,and points out the corresponding cost management measures.Based on the actual project,the method of combining qualitative analysis with quantitative analysis is used to manage the cost of jacking frame bridge in the design stage.Based on the quota design theory,the cost control of the design process is carried out,and the value engineering theory is used to evaluate and optimize the important or controversial design schemes.On the basis of the completion of the design work,the FAHP is used again to construct the hierarchical structure model of the sub project with the bottom element as the sub project.Based on the estimation results in the investment decision-making stage,the cost overrun design scheme is mainly analyzed or adjusted,so as to realize the targeted cost control in the project planning and design stage and form the estimation control budget estimate Cost management system.Finally,combined with the actual engineering construction drawing budget results,the paper analyzes the main factors influencing the project cost in the design stage from the two angles of "quantity" and "price",and summarizes the influence degree and trend of a certain extent change of a major factor on the construction cost of the jacking frame bridge.From the angle of "quantity",this paper analyzes the influence of the number of holes,the number of spans,the number of tracks and the sine of intersection angle on the square meters of the top surface of the frame bridge and the amount of reinforcement and concrete in the main body.From the perspective of "price",this paper analyzes the influence of the unit price of reinforcement,concrete and labor on the total cost of jacking frame bridge within the specified maximum range of variation.