【摘要】 寻求合理高效的方法求得构件材料阻尼特性不同结构的地震作用及其效应是工程抗震界最为关注的问题之一。近年来提出的反应谱CCQC法(Complex Complete Quadratic Combination)使问题得到了基本令人满意的解决,该法是基于黏性阻尼假定得到的,但黏性阻尼假定存在能量耗散与激振频率有关的缺陷,导致结构高频模态地震作用效应偏小。复阻尼假定避免了黏性阻尼假定的不足,但通常求得的地震作用效应为复数,不便于工程上应用。采用虚拟激励法推导出新的适合复阻尼假定和平稳随机地震动反应谱CCQC法原始表达式(Original Complex Complete Quadratic Combination,OCCQC)和传统简化表达式(Traditional Complex Complete Quadratic Combination,TCCQC),两个表达式计算结果均为实数,易于工程上应用。与平稳随机振动分析结果相比,OCCQC计算结果较接近,TCCQC计算结果偏小,说明OCCQC比TCCQC更为合理。此外,还借助模态有效质量系数提出模态截断控制方法。更多还原

【Abstract】 One of the most concerned problems in seismic engineering is to seek reasonable and efficient method to obtain earthquake action and its effects on structures of different material damping characteristics in components.In recent years,a method called response spectrum CCQC(Complex Complete Quadratic Combination) based on viscous damping assumption has been put forward and proved to be in general a satisfactory method to solve the above problem.But viscous damping assumption has disadvantages,e.g.,the energy dissipation is related to excitation frequencies,so that earthquake effects of high frequencies may be less than reality.Complex damping assumption can avoid the disadvantages of the viscous damping assumption,but usually it brings out complex form results which may be inconvenient to use.Based on assumptions of complex damping and stationary random excitation process,a pseudo-excitation method was used to acquire a new expression of complex complete quadratic combination method(OCCQC) and its simplified form according to the traditional approach(TCCQC).Results of both expressions are in real format,and can be easily used in engineering.Comparing with the results of stationary random vibration analysis,the results of OCCQC were in good agreement,while the results of TCCQC are much less,which shows that OCCQC is more rational than TCCQC.Futhermore,practical method for truncation of modes was also put forth by way of modal effective mass factor.更多还原