The Determination And Control Research Of The Expressway's Total Risk Cost

Advanced and scientific theories and methods of the construction cost management is to ensure that projects achieve the overall objective of effectively. And the cost determination and control is the core of the cost management. Since mid-1990's last century, Total Cost Management (TCM) is the new research subject in the field of international construction cost management. The TCM includes four elements which are the whole process cost management, the integrated object cost management, the total risk cost management and the whole team cost management. Among the elements, the integrated cost management and the total risk cost management are more difficult and important.In addition to the general characteristics of civil engineering projects, the expressway projects also has many special characteristics such as a long construction period, large amount of investment, significantly influenced by the construction environment as well as many participating partners. Expressway's construction and development not only represents the technological strength and the economic capability of a region or a country, but also reflects the level of the construction management. Many issues such as the excessive budget, irregular bidding market, malicious competition and even the poor quality production for lowering the construction cost occurred during the highway construction process. The cause of those problems is the construction cost management on the point of economic feature.In a long time, persons have made a progress by making a great deal of research about the mode, the theory and the method of the construction cost management. But there are still large gaps between US, Britain and our country. Furthermore, the study of the cost management in the field of highway field is weaker than in the field of building and estate where the study launched widely and deeply. So the paper makes a study of the expressway construction cost. The contents and results of the study in connection with the risk and integrated object cost are as follows:Firstly, the paper analyzed the issues and the development trends of the existing cost calculation mode. The cost estimate method basing on the artificial intelligent theory was studied. The BP neural network model is established to estimate expressway construction costs. And the model is optimized by using the theories of Fuzzy, Genetic Algorithm (GA), network integration and so on in order to enhance the stability and popularity of the model. The optimized model is verified in some examples and is proved suitable for the rapid estimation of expressway construction costs. And then, the risk factors of the expressway construction cost are analyzed. The identification, evaluation and the probability distribution discipline of the risk factors are studied deeply.Secondly, the paper studied the construction risk cost of the expressway on the comprehensive point of integrated object. The GERT (Graphical Evaluation & Review Technique) is used to analyze the relation of the time and the cost. The quantitative analysis model is built to optimize the time-cost using the analytic and simulation method. The reasonable quality determination and control method is studied on the base of TQM (Total Quality Management) theory.Thirdly, optimization analysis according to the multi objects such as time, cost and quality was done. The optimization analysis model adopting the NSGA-II (Non-dominated Sorting Genetic Algorithms) calculation method was built. The examples verified the model's feasibility of the three-objective optimization.