型钢混凝土异形柱框架地震易损性分析

摘要

In order to evaluate seismic performance of the steel reinforced concrete frame with special-shaped columns,three frames with different spatial locations and different steel forms are selected.Base on increment dynamic analysis and vulnerability analysis method,the probability that the structure can maintain the limit value of each state of the structure by input seismic wave of three fortification levels in high intensity region is obtained.At the same time,two earthquake intensity parameters PGA and Sa (T1,ξ) are compared to evaluate the effectiveness of the structure.The results show that:Sa (T1,ξ) as the earthquake intensity parameter of the structure is more efficient than PGA;under the same axial compression ratio,the seismic capacity of steel reinforced concrete lattice middle frame with special-shaped columns is the strongest,the solid middle frame is the second,the solid edge frame is the weakest.In eight degree seismic fortification intensity region,the probability of three frame which meets the code requirement of'reparable under design based earthquake'and'no collapse under rare earthquake'is higher,but the probability which meets the Code requirement of'perfect under frequent earthquake'is lower.In nine degree seismic fortification intensity region,the probability of the three frame to meet the requirements of the three fortification level is lower.%为了评估型钢混凝土异形柱框架抗震性能,选取三榀不同空间位置、不同型钢配置形式的框架,采用增量时程分析和易损性分析方法,得到三榀框架在高烈度区三种设防水准的地震作用下,保持结构各性态水平界限值的概率.同时对比了PGA和Sa(T1,ξ)两个地震动强度参数评估该结构的有效性.结果表明:以Sa(T1,ξ)作为该结构的地震强度参数比PGA更有效;以相同轴压比为条件,型钢混凝土异形柱的空腹式中框架抗震能力最强、实腹式中框架次之、实腹式边框架最弱.在8度区,三榀框架满足我国规范提出的“中震可修、大震不倒”概率较高,但满足“小震不坏”概率较低.而9度区,三榀框架保持满足三设防水准的要求概率均较低.