C80高强混凝土柱在反复荷载作用下的抗剪性能

通过1根C40普通混凝土柱与4根C80高强混凝土柱在竖向轴压力和水平反复荷载作用下的抗剪性能试验,深入研究了混凝土强度等级、剪跨比、轴压比和配箍率等因素对柱的破坏形态、滞回性能、位移延性及受剪承载力的影响.分别采用中国规范GB50010—2010、美国规范ACI318—08、加拿大规范CSA—04及桁架-拱模型对钢筋混凝土柱的受剪承载力进行计算,并与试验值进行对比分析.结果表明:对于小剪跨比钢筋混凝土柱,上述规范受剪承载力计算公式均偏于保守;由于考虑了拱效应,桁架-拱模型较其他规范对钢筋混凝土柱受剪承载力的预测更为准确.

Shear Behavior of C80 High Strength Concrete Columns Under Cyclic Loading

Experimental observations on one normal strength concrete column of C40 and four high strength concrete columns of C80 under vertical axial loading and horizontal cyclic loading were presented. The influences of concrete strength, shear span ratio, axial load ratio and transverse reinforcement ratio on hysteretic behavior,displacement ductility and shear strength of reinforced concrete( RC) columns were analyzed. Furthermore,the measured shear strength was compared with the calculated values by GB50010—2010,ACI318—08,CSA—04 and truss-arch model for shear strength.Results show that the calculated strength by the truss-arch model is consistent with the experimental observed strength of shear-critical RC columns.