500MPa细晶粒箍筋混凝土梁的斜裂缝宽度试验研究

Experimental Study on Shearing Diagonal Crack Widths of Reinforced Concrete Beams with 500MPa Hot Rolled Bars of Fine Grains

通过对16根配置500MPa细晶粒箍筋、一根配置HRB400箍筋以及一根配置HRB600箍筋的混凝土梁在集中荷载下的受剪试验,分析了混凝土强度等级、配箍率、剪跨比、截面形式以及箍筋强度对配置高强箍筋混凝土梁斜裂缝宽度的影响。短期加载试验结果表明:将500MPa细晶粒钢筋的抗拉强度设计值取为420MPa,当斜裂缝长期荷载影响系数为1.25时,则混凝土梁斜裂缝宽度可以满足正常使用阶段斜裂缝宽度为0.2mm的限值要求。

Experimental study on the shear capacity of 16 simply supported beams with 500MPa hot rolled bars of fine grains as stirrup,2 simply supported beams with HRB400 and HRB600 as stirrup respectively was made,under the concentrated loads,the effects of the concrete strength,stirrup ratio,loading form,cross-section and stirrup strength on the diagonal crack of the reinforced concrete beam with the high-strength stirrup are analyzed.The testing results indicate that if the tensile design strength of the 500MPa hot rolled bars of fine grains is taken as 420MPa,and the influence coefficient of long term sustained loading is taken as 1.25,0.2mm requirement of diagonal crack width for reinforced concrete beams can be satisfied during the limit state of serviceability.