箍筋间距对RC梁剪切破坏及尺寸效应的影响研究  

Effect of Stirrups Spacing on Shear Failure and Size Effect of RC Bseams

作　　者：金浏[1] 王涛[1] 杜修力[1] 蒋轩昂 夏海 JIN Liu;WANG Tao;DU Xiuli;JIANG Xuanang;XIA Hai(The key laboratory of Urban Security and Disaster Engineering,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学城市减灾与防灾防护教育部重点实验室,北京100124

出　　处：《防灾减灾工程学报》2021年第6期1157-1166,共10页Journal of Disaster Prevention and Mitigation Engineering

基　　金：国家重点研发计划项目(2018YFC1504302);国家自然科学基金项目(51822801,51421005)资助。

摘　　要：箍筋间距对钢筋混凝土梁的裂缝开展及剪切延性有重要影响,但对其抗剪强度及尺寸效应的影响研究较少。采用三维细观数值模拟方法,建立了钢筋混凝土梁剪切破坏力学分析模型,研究了箍筋间距及配箍率对钢筋混凝土梁剪切破坏及尺寸效应的影响机制与规律,并重点分析了箍筋间距对钢筋混凝土梁剪切延性及尺寸效应的影响。研究结果表明:箍筋间距对剪切破坏模式及抗剪强度的影响不大,主要影响钢筋混凝土梁的剪切延性;减小箍筋间距可以有效抑制梁的脆性行为;箍筋增大梁的抗剪承载能力,同时削弱梁抗剪强度尺寸效应。此外,将模拟结果与所提抗剪强度尺寸效应理论公式进行对比分析,验证了所提公式的适用性与准确性。Stirrup spacing has an important influence on the crack development and shear ductility of reinforced concrete(RC)beams,but its influence on shear strength and size effect is seldom studied.A mechanical analysis model for shear failure of RC beams was established by using 3 D meso-scale numerical simulation method. The mechanism and regularity of the influence of stirrup spacing and stirrup ratio on shear failure and size effect of RC beams were studied. The influence of stirrup spacing on shear ductility and size effect of RC beams was emphatically analyzed. The results showed that the stirrup spacing has little effect on the shear failure mode and shear strength,mainly on the shear ductility of RC beams;reducing the stirrup spacing can effectively restrain the brittle behavior of beams;stirrups increase the shear capacity of beams while weakening the size effect of shear strength. In addition,the simulation results were compared with the theoretical formula of shear strength size effect,which verified the applicability and accuracy of the proposed formula.

关 键 词：钢筋混凝土悬臂梁 箍筋间距 配箍率 剪切破坏 尺寸效应 

分 类 号：TU443[建筑科学—岩土工程]