System Dynamics-based Project Cost Risk Accession Control Modeling

In recent years, with the rapid development of project investment, "three excesses" problems (that is "the design budget exceeds the investment estimation", "diagram budget exceeds design budget", "settlement exceeds diagram budget") are serious, which brings tremendous loss to country economic construction. This paper uses system dynamics method to analyze existing influencing factors of "three exceeds" problems and their risks basing on the understanding of engineering costs and risks in different stages. As for the problems in project pricing process, this paper makes a deep research on external environment, built process, and the project's related parties and etc. to find the existing influencing factors in the three cost excesses subsystems. According to risk causal feedback figure, the paper establishes a dynamics model and makes a quantitative evaluation of the risk factors. Aiming to make recommendations to effective control of the "Three excesses" risks in project construction, this paper has a certain reference value to improve investment efficiency.