高层隔震结构等效模型研究

Research on equivalent model of high-rise isolated structure

为研究高层隔震结构的动力性能,尝试用隔震层上部子结构前两阶频率和前两阶振型与悬臂等截面直杆剪切相似且考虑上部结构总质量不变的准则推导高层隔震结构3质点等效模型.所推导的上部子结构2质点模型和全结构3质点模型较好地考虑了高阶振型的影响,分别较好地等效了剪切型高层抗震结构和隔震结构,同时发现高层隔震结构的振型质量参与系数无法体现计算振型数目的有效性;3质点模型对弯剪型高层隔震结构的等效程度虽不如对剪切型高层隔震结构的高,但其计算结果与原高层隔震结构也很接近,具有较高的等效精度.

To study the dynamic properties of high - rise isolated structure, three - particle equivalent model of high - rise isolated structure is deduced according to the rules that the first two frequency and vibration mode of the sub - structure which is upper the isolation layer and whose total mass is constant is similar to free vibration of the cantilever uniform section bar. The two - particle model of the upper sub - structure and the three - particle model whole structure which well consider the impact of higher order modes, are respectively equivalent to the shearing high - rise isolated structure and it is also found that the modal mass participation factor of high - rise isolated structure can not reflect the validity of the number of modes. The equivalent degree of the three - particle model of storey bending - shearing high - rise isolated structure is not as high as storey shearing high - rise isolated structure, but the results of which is also very close to the high - rise isolated structure and has high precision.