不同类型地震动下RC框剪结构协同工作对比分析∗

Comparative Analysis on Cooperative Performance of RC Frameshear Wall Structures under Various Types of Ground Motions

摘要:

确保强震下双重抗侧力结构的协同工作是实现多道抗震防线的关键。基于地震动特性分析，对比了普通地震动、远场长周期地震动、近断层向前方向性地震动及近断层滑冲型地震动作用下RC 框架-剪力墙结构的协同工作性能，并分析了刚度特征值及结构周期对其的影响；最后初步提出了特殊地震动作用下RC 框架-剪力墙结构考虑内力重分配的框架剪力调整方法，并将其与规范中的调整方法进行了对比。结果表明：三类特殊地震动作用下的框架剪力分担率均大于普通地震动，尤其是远场长周期地震动，在地震动强度较小时也能使框架剪力出现较大增长；周期较大结构的中下部楼层框架剪力增大较快；结构框架剪力分担率随刚度特征值的增大而增大，但内力重分配程度逐渐减小；建议在结构抗震设计时，考虑不同类型地震动特性和刚度特征值对结构内力重分配的影响。

Abstract:

Ensuring the cooperative performance of dual lateral force-resisting systems under strongearthquakes is key to developing multiple seismic fortification lines. Based on ground motion character-istics analysis, the study compared and analyzed the cooperative performance of RC frame-shear wallstructures under various types of ground motions, including ordinary, far-field long-period, near-faultforward, and near-fault fling-step ground motions. It also evaluated the effects of stiffness eigenvaluesand structural periods on performance. Additionally, a frame shear force adjustment method consider-ing the internal force redistribution under various types of special ground motions was preliminarilyproposed and compared with the adjustment method in the current codes. The results showed that theframe shear force sharing ratio under the three types of special ground motions was higher than that un-der ordinary ground motions. Especially, far-field long-period ground motions could cause a large in-crease in frame shear force even at lower seismic intensities. The frame shear force in the middle and lower floors of structures with longer periods increased faster. With the increase in stiffness eigenval-

ue, the frame shear sharing ratio also increased, but the degree of internal force redistribution gradual-

ly decreased. It is suggested that the effects of different ground motion types and stiffness eigenvalues

on internal force redistribution within structure should be considered in seismic design.