Study On Risk Assessment Of Underwater Shield Tunnel With Small Cross-Section

The theme of this article mainly developed a risk analysis and evaluates system of the building under-water tunnel; the research engineering background is Nantan river shield tunnel.The first step of the research is collection risk elements which contained in the process of the under-water shield tunnel, we need a large number of risk elements to figure out the regular that can show how the risk elements work together and finally led to the risk accident. Then, the paper rely on make some progresses in the region of existed risk analysis and evaluate methods to put forward a ease practical and more appropriate calculation methods about the risk probability and the risk contribution. When finish the former two research works and get the research results, the author combined with the background that the tunnel engineer construction investment is gradually supported by some another funds. In this trend, the result is the investor must consider their anticipated profit. So, in order to make the research results could more better use in the tunnel construction risk analysis and evaluation and more precise calculation, the author come up with a new concept of the analysis and evaluate of tunnel construction:the wealth of risk lose, this concept take the economy concept into the region of the risk analysis and evaluate tunnel engineer. Finally, the paper take a summaries and put up with a new tunnel risk analysis and evaluate method:R=P×V theory, the theory is a foundation of the tunnel constriction risk analysis and evaluates system which raised in this article.When finish the former all researches, the article eventually formed a complete set of the tunnel constriction risk analysis and evaluate system, which contained theory, methods and report.