Research On Risk Assessment Of Bridge Construction Across Sea

Construction stage is the key to decide the success of a bridge project. Because bridge engineering is usually operated under the complex social and natural environment and it have the characteristics of complex internal structure,external connections, large scale and long construction period, etc, so all above shows that the bridge engineering construction stage inevitably exist many uncertain factors. These uncertain factors means that risk is always exists in the whole process of bridge construction. If the risk cannot be avoided or eliminated, it will produce immeasurable damage to the bridge in the construction stage or operation stage and at last threat the safety of the bridge.With the sustainable development of our country economy, the number of cross-sea bridges in the coastal areas is arising. The special geographical position, complex terrain, wind, tidal bore pressure and the soft soil foundation of deep sea are bad for bridge engineering construction and bridge stress, so research on the risk of bridge construction stage has important social significance and economic significance. Under the background of the above, in this paper, coastal bridge as the main object of study, conducted risk assessment studies for its construction phase. The main contents are as follows:① Realizing the significance of bridge construction risk assessment and the present situation of the bridge construction risk assessment both domestic and overseas. The necessary of coastal areas bridge construction risk assessment is exposited by the objective need, the uncertainty of construction and the particularity of the coastal area.② Bridge construction risk is explained by the basic definition, characteristics and classification. And bridge construction risk is recognized by brainstorming method, Delphi method, scenarios analysis method, fault tree analysis method and table-manipulation method. And fuzzy analytic hierarchy process method can discern the risk source of bridge construction.③ According to the risk assessment of bridge construction method, combined with the overall risk assessment, the special risk assessment and major risk source estimate, a corresponding risk acceptance criteria are set up and risk source control measures are suggested.④ This paper uses Yueqingwan no.2 bridge as the support project, analysis the constructions which have some technical difficulty and risks such as floating pier construction, the group of pile construction, and construction of the cable tower construction cantilever construction, the upper structure construction, etc. According to the risk level evaluation standard, the construction risk level was evaluated, and risk control measures are suggested to provide important reference for the construction of the same kind of bridge.