高强钢筋和剪跨比对混凝土构件直剪性能的影响  

Effects of the HRB500 Steel Rebar and Shear Span Ratio on the Direct Shear Performance of Reinforced Concrete Members

作　　者：卢海霞[1] 林峰[1] 李彤煜[1] 

机构地区：[1]同济大学建筑工程系,上海200092

出　　处：《结构工程师》2013年第2期146-152,共7页Structural Engineers

基　　金：上海市浦江人才计划(07pj14084)

摘　　要：配置高强钢筋是否可提高钢筋混凝土构件的直剪承载力，以及在何剪跨比范围内可能发生直剪破坏，目前的认识仍不清楚。设计8个配置HRB400和HRB500钢筋的Z形直剪试件。配筋率0．48％～1．10％，通过对比试验，研究钢筋种类对直剪性能的影响。设计4个牛腿形试件，剪跨比0．21，0.43，0．74和0．87，试验研究破坏形态转变规律及直剪破坏范围。结果表明，与配置HRB400钢筋相比．配置HRB500钢筋试件的直剪承载力可提高2％-8％；随着剪跨比的增大，试件的破坏形态经历了从直剪到斜压，最后到弯曲的转变；当剪跨比小于0．3时易发生直剪破坏。Up to now, it is not clearly understood 1 ） whether the steel bar with high strength （HRB500） af- fects the direct shear performance of reinforced concrete members, and 2） in which scope of the shear span ra- tio the direct shear failure is prone to occur. To explore these aspects, eight Z type specimens reinforced with steel bars HRB400 and HRBS00 were casted, with the reinforcement ratio varying from 0.48% to 1.10%. The influences of steel bar with high strength on the direct shear performance of reinforced concrete members were studied by comparison . Meanwhile, four corbel type specimens were casted, with their shear span ratios of 0.21, 0.43, 0.74 and 0.87, respectively. Tests were also conducted to understand the transformation of failure patterns as the shear span ratio increases. It was found that the direct shear bearing capacity of speci- mens reinforced with HRB500 is 2% --8% higher than those with HRB400. With the increase of shear span ra- tio, the failure patterns of the specimens switch from direct shear to diagonal compression, and finally to flexure. Direct shear failure is prone to occur when the shear span ratio is less than 0.3 for the cases in this study.

关 键 词：直剪 剪切摩擦 HRB500钢筋 剪跨比 

分 类 号：TU375[建筑科学—结构工程]