提高钢筋混凝土剪力墙抗震性能的思想与方法

钢筋混凝土剪力墙是高层结构的主要抗侧力构件之一.位于结构底部的剪力墙承受较大的轴力、剪力和弯矩.高轴压下的剪力墙在强震作用下易发生剪切或压溃破坏,震后难以修复.如何提高底部剪力墙的抗震性能,是高层结构抗震设计的关键问题之一.从2010年智利地震和2011年新西兰地震中剪力墙震害现象出发,分析了可能引起剪力墙破坏的主要原因,详细介绍了改善剪力墙抗震性能的思想与常用设计方法.同时,针对目前超高层结构中采用的内置钢板组合剪力墙,利用数值模拟进行了参数化分析.研究表明,内置的钢板可以有效地改善剪力墙构件的受压行为,可以明显提高构件的承载力、延性和耗能能力,能有效地改善钢筋混凝土剪力墙的抗震性能.

Concepts and Measures for Improving Seismic Performance of Reinforced Concrete Shear Wall

In tall buildings the reinforced concrete (RC) shear wall is one of the predominant structural components used to resist earthquakes. Because shear walls located on the bottom zone of high-rise buildings are subjected to large axial load, shear force and moment during severe earthquakes, the shear failure or crushing of concrete usually occurs in the bottom zone of walls, and such failure mode is irreparable. Therefore, the improvement of seismic performance of RC walls at the bottom is one of the key issues of seismic design of high-rise building structures. The observed damage of RC walls in Chile earthquake (2010) and New Zealand (2011) are firstly introduced in the paper, and correlated factors which likely result in the failure of walls are analyzed. Based on the detailed assessment of seismic behavior of RC walls, concepts and measures for improving the seismic performance of RC walls are then suggested. Meanwhile, due to the increasing use of the steel plate-reinforced concrete composite shear wall (SPRCW) in super tall buildings currently, the parametric analyses of this novel structural member are carried out by numerical analysis. The numerical results indicate that, compared with the conventional RC shear walls, the embedded steel plate can efficiently improve the behavior bearing the compressive force, the load carrying capacity, ductility and energy dissipation capacity, resulting in the significant improvement of the seismic performance of RC walls.