【摘要】 为研究钢-玻璃纤维复合筋(SGFCB)作为纵向受拉筋时混凝土梁的受剪性能,进行了集中荷载作用下SGFCB混凝土梁的受剪承载力试验.试验参数为纵筋种类、构件剪跨比和纵筋配筋率.分析总结了SGFCB混凝土梁受剪破坏形态、受剪承载力和斜裂缝宽度发展随上述试验参数的变化规律.试验结果表明:SGFCB试件梁的剪切破坏形态有斜压破坏、剪压破坏和非典型的剪压破坏3种,与钢筋混凝土梁的受剪破坏形态相似.剪跨比、配筋率和配箍率相同时,SGFCB混凝土梁受剪承载力和刚度均小于钢筋混凝土梁,斜裂缝最大宽度大于钢筋混凝土梁.在试验承载力结果基础上,拟合了SGFCB混凝土梁受剪承载力-剪跨比关系曲线.最后,提出了可用于设计的集中荷载作用下SGFCB混凝土梁受剪承载力计算公式,该公式具有较高的安全保证率.更多还原

【Abstract】 To study the shear behavior of concrete beams with steel-glass fiber composite bar(SGFCB) as longitudinal tensile reinforcements, the shearing experiments of SGFCB concrete beams under the concentrated load were conducted.The experimental parameters include the types of longitudinal reinforcement, shear span ratio and longitudinal reinforcement ratio. The changing rules of failure pattern, shear bearing capacity and the development of the width of diagonal crack width of the SGFCB concrete beams under above experimental parameters were analyzed and summarized.The experimental results show that the failure patterns of the SGFCB beams include diagonal-compression, shear-compression, and atypical shear-compression failures, and all the failure patterns are similar to the failure patterns of ordinary reinforced concrete(RC) beams. When the shear span ratio, reinforcement ratio and hoop ratio are the same, the shear bearing capacity and shear stiffness of the SGFCB concrete beams are smaller than those of ordinary RC beams, the crack widths of the SGFCB concrete beams are greater than that of ordinary RC beams. On the basis of the experimental results, the curve of shear bearing capacity versus shear span ratio of the SGFCB concrete beams is fitted. Finally, the design formula of shear capacity of SGFCB concrete beams under the concentrated load is proposed. The formula guarantees a high security rate.更多还原