考虑纵筋率及加载面边长比影响的板受冲切承载力试验研究  

Experimental study on the punching shear capacity of slabs considering the influences of tension reinforcement and column aspect ratios

作　　者：黄小坤[1] 刘立渠[1] 陶学康[1] 

机构地区：[1]中国建筑科学研究院,北京100013

出　　处：《土木工程学报》2008年第7期21-26,共6页China Civil Engineering Journal

基　　金：中国建筑科学研究院标准规范研究基金(407-0411003-3)

摘　　要：纵筋率及冲切加载面边长比是影响混凝土板受冲切承载力的重要因素。对12块钢筋混凝土板试件进行了竖向冲切承载力试验研究,板尺寸为2200mm×2200mm×200mm,混凝土立方体抗压强度为39～46.9MPa,板底纵筋率有0.5%和1.3%两种,加载面边长比分别为1.0、2.0和4.0。试验结果表明:配置纵向受拉钢筋可显著提高板的受冲切承载力,但纵筋率高于2.5%时,提高作用已不明显;随着加载面边长比的增大,板的抗冲切承载能力有所降低。根据试验结果得出了试验板的荷载-挠度曲线、冲切破坏面及裂缝分布等;根据试验结果及相关文献的数据,研究分析了纵筋率及加载面边长比对板抗冲切性能的影响,得到板受冲切承载力的近似计算公式,该公式的计算值与试验值符合良好。研究结果可为我国相关规范的修订提供参考。The tension reinforcement ratio and the aspect ratio of the loading area are two important factors that influence the punching capacity of concrete slabs. Twelve reinforced concrete slabs were tested under vertical punching loads. The slabs dimension is 2200 mm×2200 mm×200 mm, with concrete cubic compressive strength of 39-46.9 MPa, tension reinforcement ratios of 0.5% and 1.3%, column aspect ratios of 1.0, 2.0 and 4.0. Experimental results reveal that increase in the flexural reinforcement ratio could enhance the punching shear strength, but the enhancement is insignificant when the reinforcement ratio is greater than 2.5%. Increasing the column aspect ratio could decrease the punching shear strength. Based on the test results, the load-deflection curves, the punching failure surfaces and crack distributions of the slabs are presented. According to the test results and the collected reference test data, the effects of the tension reinforcement and column aspect ratios on the punching failure are studied, and the formula for punching shear capacity is proposed. The calculated results agree well with the test results. The results could provide a reference for revision of the relevant national standards.

关 键 词：试验研究 钢筋混凝土板 纵筋率 加载面边长比 受冲切承载力 

分 类 号：TU375.2[建筑科学—结构工程]