Long-span Constinuous Bridges Risk Management Research

Risk arises from the uncertainty of reality and the limitation ofsubjective awareness. It can be found everywhere and every moment.Generally speaking, its uncertainty can be revealed as benefits andopportunities gained from it, what’s more, it can also be expressed as lossand damage gotten. Naturally, we all tend to favor the benefits and avoid thedamage. Risk events are occasional but they appear everywhere. After adetailed observation of them, it is found that their appearance is regular;therefore, it is necessary that researches should be done to deduce properanti-risk measures which help lower risk to the lowest level.Bridge engineering plays an important role in the development ofhuman civilization, and in some way it can even be said that bridgeconstruction capacity represents the comprehensive traffic standard of ourcountry. As far as extremely large bridge engineering is concerned, structureis the weakest in the construction process for its complex technology;therefore, the risk is uncertain, complex and unavoidable. With thedevelopment of scientific technology, the bridge construction technology isimproved; in the meantime, the risks in the construction process are alsodiversified. Therefore, it is of great significance that a risk managementsystem which knows well the risks in the bridge construction process shouldbe built to control and reduce risk effectively.Based on the actual needs of continuous beam bridge, this thesisconducts an analysis of the risks in the construction process. To put it intodetail, the qualification of index weight is guided by fuzzy mathematics;moreover, analytic hierarchy process and fuzzy synthetic evaluation arecombined to carry out a multi-level fuzzy comprehensive evaluation. Thisanalysis not only summarizes and studies risk resources during theconstruction process, it also builds a risk factors bank which does a comprehensive study of all kinds of risk factors in the construction phase ofcontinuous beam bridges. To put it into detail, the risk factor bank concludesrisks in foundation and superstructure construction in Continuous BeamBridge, besides, the risk control in the construction phase is also studiedfrom man-made risk control, and some relevant suggestions and measuresare put forward.Based on the Fuhe extremely large bridge, this thesis identifies the riskfactors in the construction phase of long-span continuous beam bridge indetail, and analytic hierarchy process is also used to analyze and rank themain risk factors, and then some relevant preventive measures and strategiesare also provided.