CRB550级箍筋混凝土梁的抗震性能对比试验

为揭示CRB550级箍筋混凝土梁的抗震性能,按等强度准则设计了18个不同纵筋配筋率、箍筋强度等级、箍筋直径的钢筋混凝土梁构件,并对其进行低周反复作用下的拟静力试验,分组对比分析骨架曲线、延性和耗能性能.结果表明：a.在箍筋强度相等的前提下,较小直径CRB550配箍的混凝土梁试件与满足规范最小直径的HPB235配箍的混凝土梁试件相比,在纵向筋配筋率中等和偏大情况下延性要好,在纵向配筋率偏小的情况下延性稍弱但相差不大,两者承载力相差不大;b.在能量耗散方面,各对比组中按等强原则采用较小直径CRB550配箍的混凝土梁试件与对应的HPB235,HPB335配箍的混凝土梁试件的等效黏滞阻尼系数基本相同,归一化总滞回耗能也相差无几,都具有很好的耗能能力.

Comparative experimental research on earthquake-resistant behavior of reinforced concrete beams with CRB550 stirrups

In order to reveal the seismic performance of concrete beam of CRB550 level stirrups,18 reinforced concrete beams which constitute from different reinforcements,different intensity levels and diameters of stirrups were designed and carried out quasi-static experiment under low cyclic loading.The skeleton curve,ductility and energy dissipation were compared.Under the same strength,the RC(reinforced conctrte) beam of smaller diameter CRB550 stirrups were compared with the RC beam of HPB235 stirrups,in the case of medium and larger longitudinal reinforcement ratio,and the results show that,ductility of beams with CRB550 stirrups were better than beams with HPB235 stirrups,and in the case of lower longitudinal reinforcement ratio,both ductile and capacity have little difference.In terms of energy dissipation,the CRB550 level concrete beam specimens of a smaller diameter were compared with the corresponding HPB235,HPB335 stirrups concrete beam specimen,and the equivalent viscous damping coefficients are basically the same,normalized total hysteretic energy is also similar,and both have good energy dissipation capacity.