【摘要】 多点输入计算中,在考虑所有耦合项的完全二次项(CQC)组合法基础上,给出忽略相关耦合项的平方和平方根(SRSS)近似算法,并针对两点支承结构的特殊性,提出该类型结构拟静力响应的简化计算方法。以典型的两种两点支承结构为算例,分析SRSS近似算法的精度。计算结果表明,对于两点支承结构而言,SRSS算法的误差主要是因为忽略拟静力和相对动力耦合项所致,而忽略振型耦合项的误差较小;行波效应越强,近似算法的误差越大;但从实际工程结构的计算结果来看,在常见的波速范围内,两种近似算法的位移、内力的计算误差都分别在10%、15%以内。因此采用SRSS近似方法用于此类结构多点输入地震响应的计算是可行的。更多还原

【Abstract】 On the base of response spectrum CQC method considering all the coupling items,an approximate SRSS algorithm ignoring relevant coupling terms was given. Due to the specialty of structures with two supports,a simplified algorithm for analysing quasi-static response of this type of structures was put forward. Taking a typical two supports structure as example,the accuracy of the approximate algorithm of SRSS was analyzed. The results show that the error of SRSS method mainly comes from ignoring quasi-static and relative dynamic coupling terms,but not modal coupling terms.The stronger the traveling-wave effect is,the bigger the error of the approximate algorithm will be. But according to the calculation results of actual engineering structures,within the range of the common wave velocity,the computation errors of displacement and internal force of the two approximate algorithms keep within 10% and 15% respectively. So it is feasible to use approximate algorithm of SRSS for seismic response analysis of two supports structures under multi-support excitation.更多还原