高强箍筋高强混凝土梁受剪试验研究  

Experimental study on shear behavior of high-strength concrete beams with high-strength stirrups

作　　者：易伟建[1] 吕艳梅[2] 

机构地区：[1]湖南大学土木工程学院,湖南长沙410082 [2]广东省建筑设计研究院,广东广州510010

出　　处：《建筑结构学报》2009年第4期94-101,共8页Journal of Building Structures

基　　金：国家自然科学基金资助项目(50678064);湖南省重大科技计划资助项目(06FJ3003)

摘　　要：设计了一套使钢筋混凝土梁剪切破坏稳定可控的刚性试验系统,利用该试验系统,完成了19根剪跨比为3的钢筋混凝土简支梁的剪切破坏试验,得到了荷载-挠度曲线。根据试验结果,分析了混凝土强度等级、箍筋的强度和倾角、纵筋配筋率和纵向分布钢筋等因素对试验梁破坏形态、剪切延性系数和受剪承载力的影响,并将受剪承载力试验值与我国混凝土结构设计规范和美国ACI规范计算值进行了对比。结果表明:对于剪跨比等于3的梁,适当配置腹筋,可以改善其延性性能;在高强混凝土梁中应用高强箍筋,可使两种材料的强度充分发挥,不仅增加了梁的剪切延性,而且提高了梁的受剪承载力;高强箍筋高强混凝土梁的受剪承载力仍可采用我国现行混凝土结构设计规范公式进行计算,但是对于高强混凝土无腹筋梁、纵筋配筋率低的梁和配有高强箍筋的普通强度混凝土梁安全度偏低。A stiff test facility was developed for obtaining stable and controlled shear critical of reinforced concrete beams. A total of 19 reinforced concrete beams with shear span-to-depth equal to 3 were tested in the testing facility, and complete load-midspan deflection curves were obtained. Based on the data of tested beams, first, the effects of concrete strength, stirrups strength, inclined stirrup angle, the amount of longitudinal reinforcement on model of failure, shear ductility coefficient and shear capacity were analyzed. Then, the shear strength of test beams were compared with the shear design approaches of China code for design of concrete structures and America ACI code. The results indicate that when shear span-to-depth equal to 3, shear failure in the beams with appropriate web reinforcements have a definite ductility. In addition, high-strength concrete beam, reinforced with high strength stirrups, can increase greatly not only the shear ductility, but also the shear capacity. Besides, the shear capacity of beams with high-strength concrete and stirrup can be still designed by current China code, but the shear design approach in the code is unsafe for high-strength concrete beams without web reinforcements, beams with the smaller amount of longitudinal reinforcement and the normal strength concrete beams with high-strength stirrups.

关 键 词：混凝土梁 高强混凝土 高强箍筋 静力试验 受剪承载力 剪切延性 

分 类 号：TU375.1[建筑科学—结构工程] TU317.1