Probability Evaluation Method for Cable Safety of Long Span Suspension Bridges under Extreme Wind Load

Abstract

The cable is the main load-bearing component of suspension bridge and its safety assessment under extreme wind load is a key issue to the structure. Take a long-span suspension bridge in the East Sea China as an example, the standard of extreme wind load for structural safety evaluation is established; the wire’s strength model is established by the type I extreme value distribution; cable’s safety assessment function under wind load is established and the Monte Carlo method is used to get the cable’s reliability and reliable indicators. The bridge’s re-service term is taken for 90 years as an example, the results indicate that the wire’s serial effects can’t be ignored, the cable’s reliable indicator decreases as the number of broken wires increases in approximately the linear attenuation relations, the critical percentage of broken wires is about 10%.