塑性铰区中纤维增强混凝土的抗震性能研究

Seismic Behavior of Fiber Reinforced Concrete in Plastic Hinge Zone

为了提高钢筋混凝土柱的抗震性能,考虑在潜在的塑性铰区中通过纤维增强混凝土(FRC)代替普通混凝土。设计了6个钢筋混凝土柱试样,其柱中的剪跨比为3,且箍筋较少。其中,有5个试样在潜在的塑性铰区中使用了FRC。通过改变FRC区的高度、强度以及柱的轴向压缩比,观察了低水平荷载作用下试件的裂纹发展和破坏过程,以及试件的滞后特性、变形能力与承载力。结果表明,钢筋混凝土柱的塑性铰区采用FRC,其破坏模式为纵向应力增强屈服后的剪切破坏,具有更好的变形能力和损伤承受能力;局部使用FRC可以减少约束箍筋和剪切箍筋的数量。

In order to improve the seismic performance of reinforced concrete columns, fiber reinforced concrete(FRC) is considered to replace ordinary concrete in the potential plastic hinge area. Six reinforced concrete column samples are designed, the shear span ratio is 3, and the stirrups are less. Among them, 5 specimens used FRC in potential plastic hinge area. By changing the height, strength and axial compression ratio of the FRC zone, the crack development and failure process, as well as the hysteretic characteristics, deformation capacity and bearing capacity of the specimens under low horizontal load are observed. The results show that the plastic hinge zone of reinforced concrete column adopts FRC, and its failure mode is shear failure after longitudinal stress enhanced yield, which has better deformation capacity and damage tolerance. Local use of FRC can reduce the number of restrained stirrups and shear stirrups.