Bridge Structural System Operators Risk Assessment Method

The surrounding of bridge construction is so complex that there are lots of risk factors that would have an adverse impact on bridge even make it break down. Therefore, it is necessary to make risk assessment to it with fast development of bridge construction. Relatively speaking, the research of risk assessment to bridge starts later, so that the theoretical system and calculation method of it have not formed. This disquisition mainly research for calculation method of risk assessment to bridge, and the main content is showed as the follows:(1) The uncertain Analytic Hierarchy Process is applied to the process of risk assessment to bridge on the basis of analyzing and comprehending kinds of methods about risk assessment. This kind of method of risk assessment is mainly applied to integrative assessment to all risk factors, so the scale of them can be calculated in this method.(2) The group decision-making and the principle of set-valued statistics are applied to the risk assessment to bridge with the uncertain Analytic Hierarchy Process. The influence of the subjective factors can be maximally reduced with using these theories integratively, so it could make the scale more external.(3) Bridge's disaster events of domestic and foreign are aggregated on the basis of beforehand research. The system of risk identification is constituted. The risk factors can be filtered according to it, and the subordinate of risk factors that influence the bridges slightly can be deleted, so the workload of risk assessment could be reduced mostly.(4) The definite method of risk consequence rank is studied. The theory of structural reliability is applied to confirm rank of the risk consequence according to correlative criterions. In this process, risk factors are converted to the form of loading of the bridge structure, and then the software of finite element method is applied to calculate the distributing chart of internal force and find the section that is likely to be disabled as control section. According to the theory of structural reliability, the value of structural reliability is calculated by the influence of this risk factor, and then the rank of the risk consequence can be confirmed by the value of structural reliability.The method of risk assessment to bridge is studied on the basis of these researching and applied to practical project. It gropes for the theoretical system of risk assessment to bridge.