高强箍筋高强混凝土柱抗震性能试验研究

通过6根复合箍筋约束高强混凝土柱在高轴压力低周往复荷载作用下的加载试验,研究了其破坏过程、破坏形态、滞回特性、延性性能及耗能性能,分析了箍筋的应力水平。高强箍筋试件与普通箍筋试件的对比分析结果表明:提高箍筋强度不能提高试件水平承载力,但可以显著提高其变形能力和耗能能力;试件达到极限位移时,高强箍筋约束核心混凝土未见明显压碎,箍筋未屈服,依然对核心混凝土有较高的约束作用;在同等配箍率下,密配细直径箍筋比疏配粗直径箍筋对提高构件抗震性能更为有效。

EXPERIMENTAL STUDY ON SEISMIC BEHAVIOR OF HIGH-STRENGTH CONCRETE COLUMNS WITH HIGH-STRENGTH STIRRUPS

The experiments of six high-strength concrete columns confined with composite stirrups were performed under high axial compression forces and low cyclic reversed loading. The failure process,failure modes,hysteresis characteristics, ductility and energy dissipation are investigated, and the stress level of the transverse reinforcement is evaluated. The results of the comparison between high-strength stirrup columns and normal-strength stirrup columns indicates that increasing stirrup strength is not helpful to the increase in the lateral bearing capacity of specimens, however, it can improve the ductility and energy dissipation of specimens significantly. At the ultimate displacement, the core concrete confined with high-strength stirrups was not crushed obviously, furthermore, stirrups did not reach the yield strength and could supply efficient confinement to the core concrete. At a given stirrup ratio, the aseismic behavior of columns with small stirrup spacing and stirrup diameter is better than those with large stirrup spacing and stirrup diameter.