基础隔震结构考虑摆动的振动控制研究

Study on vibration-control of base isolated structures with swing

在基础隔震结构中,当上部结构层间刚度相对较小、垂直荷载较大,且采用的叠层橡胶垫的橡胶总厚度较大时,隔震支座不仅要产生水平变形,同时也会产生竖向变形,导致上部结构产生摆动.文中推导了基础隔震结构考虑摆动的运动和控制方程,分析研究了摆动对基础隔震结构的振动控制影响.研究结果表明:基础隔震结构的摆动对控制有一定影响;隔震层转动刚度、阻尼和上部结构垂直荷载对基础隔震结构考虑摆动的振动控制有明显影响.

Upper story rigidity of base isolated structures is smaller,and the isolated structure bears a bigger vertical load,a multi-story rubber pad is adopted,the total thickness of the rubber bearing is bigger and it has not only an obvious horizontal but also vertical displacements.It causes the upper storys to produce swing.The vibrations and the control equations of a base isolated structure with swing are derived,analyzes the swing＇s influences to the vibration-control of the base isolated structure are analyzed.The conclusions obtained from above analysis suggest that the swing may have some influences to the vibration-control of the isolated structures.The rotation rigidity and damping ratio of the base isolated structure and superstructural vertical load obviously influence the vibration-control of the base isolated structures with swing.