Risk analysis for decision support system of risk management in building projects

This paper presents the risk analysis for decision support system of risk management from the viewpoints of site managers in Japan. In the past decade, both inside and outside of Japan, a lot of studies and researches have been done oil the problems concerning the risk management process, the contract relation, and the development of risk analysis technique. However, there are very few studies discussing the project risk from the viewpoints of jobsite engineers (Tsai et al., 2001). Especially risk management, which has been usually processed in the empiricism, is not considered very much oil the construction sites in Japan. Moreover, the studies about risk management are still in a qualitative discussion concerning the reasonable relationship and responsibility allocation among the related stakeholders in the contract. However, it is necessary to understand the quantitative mechanism of project risk as much as possible to proceed risk management in the construction site properly, and set tip the risk strategies by trade-off of risk and cost to reduce the project risk (Tsai et al., 2001). This study started with a discussion about the concept and the description of project risk with 40 site managers by brainstorming. And, 650 risk occurrence causes in very concrete description are emerged. The 105 risk categories (see Table 1) and 251 risk occurrence causes are classified in abstraction description based on these 650 risk occurrence causes. In the questionnaire survey, the quantitative and qualitative data of about 251 risk occurrence causes were collected from 22 construction projects in Kansai area of Japan. These data are analyzed from multiple dimensions to search the co-relationship among risk causes, risk strategies, project phases, and risk results. Finally, the framework of analysis model and the decision support system of risk management in the construction phase of construction projects are developed. Also, other risk occurrence causes which relate to these risk results can be displayed according to user's requirement In addition, the scenario of the trade-off of the risk in the project is simulated from the relations among the risk of each risk occurrence cause, the cost of the forecast damage, the risk strategies, and the strategies cost, etc. by the selection in a dialogue mode. In other words, a primary/qualitative analysis concerning each risk occurrence cause in the project risk is proceeded according to historical data.