Anti-slip Safety Design of Gravity Anchorage of Suspension Bridges with Over-2 000-meter Main Spans
Design specifications for bridges are not applicable to over-2 000-m-long suspension bridges.The traditional design method with overall factors of safety reflects the safety margin of the bridge using average or standard values,and the failure probability calculated by resistance and load effects cannot be considered in the method.In this study,the statistical characteristics and variability of the load,resistance,and design parameters of the anchorage are discussed.Based on a reliability analysis,a limit state equation was established for the sliding of the gravity-type anchorage(GTA)of suspension bridges.Given the target reliability index,partial factors of resistance were discussed,and the expression of the equivalent factor of safety was deduced.Considering the world's longest suspension bridge spanning 2 300 m as an example,design equations with partial factors were established for the sliding resistance of the GTA of super-long-span suspension bridges,and a comparison was performed with the traditional design method with the overall factors of safety.The results show that the equivalent factors of safety considering the sliding of GT As are significantly decreased by the limit state design method with partial factors.This design method is highly scientific and cost-effective.It also provides a theoretical basis and technical support for the design specifications of over-2 000-m-long suspension bridges.
bridge engineeringover-2 000 m-long suspension bridgedesign methodanchoragesafety margin of anti-slipreliability
万方数据
