Artificial Cost Simulation Study Of Subway Project In Shield Construction

Subway is the main form of urban rail transit.Subway can relieve the pressure of urban traffic and promote urban construction,so it develops vigorously in various cities.However,the huge investment in the subway system and the high construction cost have increased the economic burden of all parties involved.In recent years,the number of labor force has decreased sharply,making the labor cost increase year by year.How to accurately predict the labor cost of shield tunneling subway project has become the key point of labor cost management and control.In this paper,based on system dynamics theory knowledge,with the aid of Vensim-ple software,established can reflect the subway shield construction project change rule and trend of development of the artificial cost system dynamics model of subway in xiamen adjacent north station ~ peng CAI shield interval adjacent station as an example,this subway shield construction project cost of artificial simulated prediction.At the same time,scenario analysis is carried out by changing different parameter values or combinations.The main research results of this paper are as follows:(1)By comparing and analyzing the quota and using the rules of labor cost composition,the subsystem division of labor cost of shield construction subway project was carried out to identify the main influencing factors of labor cost.According to the composition of the current labor cost,after studied all kinds of shield project quota,combined with the survey method,observation method,the method of literature study method and experience summary method,in line with concise,two necessary principle,artificial subway shield construction project cost according to the process of construction process is divided into shield machine hoisting hanging down the cost of artificial cost,frame installation dismantled,shield tunneling of the labor cost,etc.7 subsystems.According to the constitutive factors of labor cost(labor unit price and labor day consumption),the main influencing factors of labor cost in shield construction subway project are analyzed and identified.(2)By analyzing the influencing factors of the labor cost of shield tunneling subway project,a simulation model of the labor cost of shield tunneling subway project was established using the system dynamics principle.Based on system dynamics system after learning,the combination of shield construction of subway project related theory knowledge,establish the system goal is under the influence of many variables and constraints,explore the subway shield construction project change law and tendency of the development of artificial cost.After defining the system boundary of clear,to shield construction of subway project construction process each subsystem factors analysis,considering the relationship between various factors,draw the causality diagram.Based on the causal diagram,the system flow diagram is drawn after considering the attributes of variables(i.e.state variables,rate variables,auxiliary variables and constants).The equation is established in accordance with the actual situation.In order to determine the role of the model,the model test was carried out.(3)Take the shield interval of xiamen subway from pengcuo north station to caicuo station as an example for empirical study,and draw some conclusions.In xiamen city rail transit line 4 4 standard 3 work area adjacent north station ~ peng CAI adjacent station shield interval for empirical research,combined with the project construction organization design and construction of the quota,the values of model parameters.Through the operation of the model,the labor cost of the subway project during shield construction in this section is predicted.The results showed that the total labor cost in the shield section was 21.8783 million yuan,accounting for about 8.98% of the total cost of the project.Combined with the length of the interval,the average labor cost per ductile of shield interval is 5004.76 yuan.After comparing the cost of each subsystem,the ranking is carried out,among which the labor cost of prefabricated pipe piece accounts for more than half of the labor cost of shield construction subway project,which needs to be controlled emphatically.A number of subproject simulations have been carried out with little difference from the actual comparison.The situation analysis is carried out by changing the assignment of different parameters in the model.The results show that the labor cost of subway projects under shield construction is affected by the non-linear factors such as labor unit price,shield tunneling speed and cutter diameter.