钢管桩码头地震易损性分析的单自由度模型

Single-degree-of-freedom model for seismic fragility analysis of steel pipe pile-supported wharves

结构地震易损性分析的关键是确定结构在不同地震动强度下的反应值。由于需要考虑地震动的不确定性,须对大量地震动记录进行统计分析,特别是直接对码头结构进行抗震分析的情况下,计算量很大。为降低钢管桩码头易损性分析的复杂程度,提出一种可用于码头易损性分析的单自由度模型,该模型采用曲线型骨架线和Masing准则模拟钢管桩码头的恢复力特性。为验证该模型的合理性和有效性,将一个钢管桩码头结构等效为单自由度模型,并基于云图法分别对原型结构和单自由度模型进行了易损性分析,结果表明二者的易损性曲线吻合良好。

The key of seismic fragility analysis for structure is to ascertain the structure response values under various earthquake ground motion levels.Due to the uncertainty of ground motions,a large number of ground motion records need to be statistically analyzed.The computation cost will be huge,especially when the seismic analyses are directly performed on wharf structures.In order to reduce the complexity of fragility analysis of steel pipe pile wharf,we proposed a single-degree-of-freedom(SDOF)model for seismic fragility analysis of steel pipe pile-supported wharves,which utilizes curvilinear backbone curve and Masing rule to mimic the restoring force characteristics.In order to verify the rationality and effectiveness of the proposed model,a steel pipe pile wharf structure is equivalent to the single degree of freedom model,and the fragility analysis of the prototype structure and the single degree of freedom model is carried out based on the cloud diagram method.The results show that the fragility curves of the two models are in good agreement.