基于MCFT理论的配斜筋RC梁抗剪承载力计算  

Calculation of Shear Capacity of RC Beam with Diagonal Reinforcement Based on Modified Compression Field Theory

作　　者：张建仁[1] 孙乐坤[1] 马亚飞[1] 王磊[1] 刘彬[1] 

机构地区：[1]长沙理工大学桥梁工程安全控制省部共建教育部重点实验室,湖南长沙410114

出　　处：《公路交通科技》2012年第9期58-63,共6页Journal of Highway and Transportation Research and Development

基　　金：国家自然科学基金项目(50878031)

摘　　要：针对桥梁工程中常用的配斜筋钢筋混凝土梁剪压破坏的情况,视梁截面的剪力由剪压区混凝土、箍筋和斜筋共同承担,以修正压力场(MCFT)理论为基础,考虑斜筋对裂缝处应力的影响,通过建立平均应力和斜裂缝处局部应力平衡方程,结合混凝土的变形协调条件和材料的本构关系,分别对受压区和受拉区混凝土抗剪承载力做出计算,提出了极限抗剪承载力的计算方法,并与2根实验室自制配斜筋RC梁的抗剪承载力试验结果进行了对比。研究结果表明理论值与试验值吻合较好,验证了该方法的有效性,可为相关承载力计算提供参考。For the compression-shear failure of reinforced concrete bridge beam with diagonal reinforcement, the calculation method of ultimate shear capacity was proposed based on the modified compression field theory （MCFT）. Regarded the shear of beam section as shared by concrete, stirrups and diagonal reinforcements at shear compression zone, considered the effect of diagonal reinforcement on stress of diagonal cracks, the new balance equation between the average stress and the internal force of cracked concrete was established. Combined with constitutive relations of materials and the deformation compatibility of concrete, the shear capacities of concrete in tensile and compression areas were calculated respectively. The theoretical shear capacity predicted by MCFT was validated by a comparison with the experimental result of two homemade reinforced concrete beams with diagonal reinforcement, which provides a reference for the capacity calculation of reinforced concrete beam.

关 键 词：桥梁工程 钢筋混凝土梁 抗剪承载力 修正压力场理论 斜筋 

分 类 号：U448.34[建筑科学—桥梁与隧道工程]