Research On Construction Risk Of Railway Bridge In Collapsible Loess Area

The construction of railway-bridge is long with much investment and many factorswhich is not in the scope of controlling. From shifting materials to site to completion ofacceptance every section has a lot of risks which will bring loss. The uncertainty decidesnecessity of risk management. In the west collapsed loess area, construction risk is differentbetween west collapsed loess area and other areas, so risk management should be emphasizedand give suggestion about risk management in this area now and in the future. The mainresearch on construction risk management of railway-bridge in collapsed loess as follows:(1)Identification about the construction risks of railway-bridge which maybe occurredwas studied. Summarize characteristics of railway-bridge construction projects andparticularity of risk in collapsed loess. According to risk management procedure recognizingconstruction risk factors in this area and then build3layers index system. The first layer istarget layer that is construction risk management of railway-bridge in collapsed loess area.The second layer is criterion layer which include technical risk, management risk,environmental risk, political and legal risk, economic risk. Through choosing risk factorsstrictly, the third layer is divided into15indexes that is loess foundation treatment, pierconstruction method, upper bridge construction method, vibration isolation measures, qualityrisk, duration risk, cost risk, contract risk, loess and collapsible degree, earthquake, otherunpredictable weather, laws and regulations change, tendency of local polity, inflation risk,interest rate and exchange rate risk.(2) Apply gray theory to construction risk of railway-bridge. Use grey matrix albino andgrey clustering as risk assessment method based on comparing risk evaluation methods. Givecoping strategies and measures to construction risk of railway-bridge.(3) Applying gray theory into risk management with the case Lan Yu Railway YangJiawan Bridge. Consulting Interim Provisions for Risk Assessment and Management forRailway Tunnel and The Highway Bridge and Tunnel Engineering Safety Risk AssessmentGuide, the risk is divided into4degrees: low, moderate, high, very high. Ascertain riskfactors by feedback information of questionnaires. Combine grey theory to evaluate Lan YuRailway Yang Jiawan Bridge. The conclusion is that gray degree is second degree and risk degree is moderate. Rank the risk factors comprehensively to confirm the important factorsand give coping measures to them.