The Study Of Bridge Engineering Insurance Rate Based On Reliability

As the key of the transportation system, the bridge engineering has great significance for developing national economy and improving the living standard. Tremendous loss in economy and other calamities will be brought about due to the damage of bridge systems in the accidence and natural disasters. Therefore, the essential problem is how to ensure the gathering of the funds used in bridge repairment and renovation with high priority. According to the practice of the developed market economy, bridge engineering should also resort to the insurance. The insured can shift most of its construction risks threatening benefits of the project to a professional risk-bearer-insurance company, because the insurance is one of the effective means of distributing and shifting risks and compensating for economic loss.The risk of bridge engineering project is complicated. There are variations in risk levels for two projects with same structure because of the differences in their locations, construction methods and so on. This brings about the special charater of bridge engineering insurance, which suggests that bridge engineering insurance has no fixed premiem rate and the rate level depends on the level of risk of each project. At present, the domestic method of calculating the engineering insurance rate is not appropriate, for it lacks the individual risk analysis. To solve this problem, the author proposes a method, which is based on structural system reliability and combines the bridge system theory with the engineering risk analytic theory, calculating the rate in a creative way. And we can get the insurance rate in operational stage base on time-varying structural reliability.After studying the caculation of bridge engineering system reliability and the common principle of engineering insurance, the author brings forward the method of pursuing the bridge engineering insurance rate. According to this method, knowledge of probability are used to calculate the basic rate which reflects the common character of all bridge engineering projects. Futhermore, a reliability model of reinforced concrete beam bridge is built. The system reliability is obtained by combining reliability of structure components. According to expected loss of bridge system, the author deduces the formula of caculating insurance rate. A case is domenstrated to prove the feasibility of this method, furtherly showing the inappropriation of the current engineering insurance rate.