钢筋混凝土矩形空心墩受剪承载力研究

Research on shear strength of rectangular hollow reinforced concrete piers

为准确计算钢筋混凝土矩形空心墩受剪承载力,验证实心墩计算模型的适用性,本文基于桁架-拱模型建立了考虑位移延性需求的矩形空心墩受剪承载力计算模型。通过从国内外文献中收集的共22组矩形空心墩受剪试验数据,对比分析了已有模型与本文提出模型的适用性、有效性和准确性。结果表明:Priestley模型、Aschheim模型和Sezen模型均高估了矩形空心墩的受剪承载力;Kowalsky模型和JTG/T 2231-01-2020模型计算结果偏于保守;Shin模型计算高强混凝土矩形空心墩受剪承载力时偏于不安全,不同箍筋强度下计算结果离散性较大;本文所提出模型能较为准确地计算不同混凝土强度等级和不同箍筋强度等级矩形空心墩的受剪承载力,计算结果与试验结果吻合较好且离散性小。

In this study,a shear strength model for rectangular hollow reinforced concrete piers(RHRCPs)was proposed,which accounted for displacement ductility demands based on the truss-arch model,to accurately calculate the shear strength and to verify the applicability of shear models of rectangular solid reinforced concrete piers for RHRCPs.The applicability,validity,and accuracy of existing shear strength models and the proposed model were compared and verified via twenty-two groups of RHRCP shear test data taken from domestic and foreign literature.The results indicated that the Priestley model,Aschheim model,and Sezen model overestimate the shear strength of RHRCPs,while the Kowalsky model and JGT/T 2231-01-2020 model were more conservative.The Shin model was determined to be unsafe for calculating the shear strength of RHRCPs with high-strength concrete,and large errors from RHRCPs with stirrups of different strength grades.The proposed model provided relatively precise results for RHRCPs with different strength grades of concrete strength and stirrups,and the theoretical results were in good agreement with experimental results,with relatively small errors.