采用消能连梁的高层框架-核心筒结构减震方案分析

Damping Scheme of High-rise Frame Core Wall Structure with Energy Dissipation Coupling Beam

高层框架-核心筒结构在我国大中城市应用较多,该类建筑往往功能复杂且内部人口密集,若地震中发生严重破坏将造成严重的经济损失和人员伤亡。为了有效控制该类结构地震损伤,利用截面优化型消能连梁对其进行减震设计,通过比较多种减震方案对整体结构地震损伤控制的影响选择最优的减震设计方案。以某17层框架-核心筒结构为算例,采用MSC.MARC有限元软件建立数值模型,利用算例结构缩尺振动台试验现象以及截面优化型消能连梁拟静力试验结果,验证了该数值模型的准确性。进一步利用该数值模型对结构进行动力时程分析,通过层间位移角、损伤云图、附加阻尼比等指标综合对比各减震方案的效果。结果表明:消能连梁的刚度与原结构混凝土连梁相等,且强度略低于原结构混凝土连梁,约为0.8倍时,对整体结构的损伤控制效果最佳;当消能连梁在各楼层满布时,对结构整体的损伤控制效果最好;大震工况下,按上述满布方案设计的消能连梁可以减小结构26.3%的层间位移角,使结构的附加阻尼比达到8.73%。本研究为该类高层结构的消能减震设计提供了参考方案。

High-rise frame-core wall structure is widely used in large and medium-sized cities in China,with complex building functions and densely populated interior.If severe damage occurs in earthquake,it will cause serious economic loss and casualties.In order to control the seismic damage of this kind of structure and the damping design of the energy dissipation coupling beam with optimized section is carried out,then many design schemes are compared to choose the best one,a 17-story frame-core wall structure is taken as an example,the numerical model is established by using MSC.MARC finite element software,and the accuracy of the numerical model was verified by the results of the shaking table test of structure and the pseudo-static test results of the energy dissipation-coupling beam.Furthermore,the dynamic time history analysis of structures with various damping schemes was carried out by using the numerical model,and the comparison analysis was carried out through many indexes about drift angle,damage nephogram and additional damping ratio.The results show that the stiffness of energy dissipation beam is equal to that of the original structural concrete beam,and the strength is slightly lower than that of the original structural concrete beam,which is about 0.8 times,and the damage control effect of the whole structure is the best.The damage control effect is the best when energy-dissipating coupling are fully distributed on all stories.Under the condition of large earthquake,the energy-dissipating coupling beam designed according to the above scheme can reduce the drift angle of the structure by 26.3%and make the additional damping ratio of the structure reaches 8.73%.This study provides a scheme for the energy dissipation and shock absorption design of such structure.