基于试验数据的带端柱或翼缘钢筋混凝土剪力墙抗剪承载力评估和分析

Evaluation and analysis of shear capacity of barbell-shaped or flanged reinforced concrete walls based on experimental data

建立了一个包含305个带端柱或翼缘钢筋混凝土剪力墙试验数据库。根据有无腹筋、加载方式、破坏类型将数据筛选分成7类,将数据库与《高层建筑混凝土结构技术规程》(JGJ 3—2010)中对应的抗剪承载力公式计算结果进行对比。结果表明,对于带端柱或翼缘钢筋混凝土剪力墙,抗剪承载力实测值与各抗剪承载力公式计算值比值的离散性均较大,对于永久、短暂设计状况下剪压公式,其钢筋部分抗剪公式不准确导致整个剪压公式不准确,而对于地震设计状况下剪压公式,混凝土部分抗剪公式不准确使得整个剪压公式计算结果的准确度降低。基于试验数据库,对永久、短暂设计状况下剪压公式的钢筋部分抗剪公式,地震设计状况下剪压公式的混凝土部分抗剪公式以及剪跨比不大于2.5斜压公式进行修正,使计算结果符合试验规律。给出适应于计算带端柱或翼缘钢筋混凝土剪力墙的抗剪承载力修正公式,将修正公式的计算值与实测值对比,结果表明,修正公式的准确性较高。

An experimental database was established containing 305 barbell-shaped or flanged reinforced concrete walls.According to the web reinforcement,loading mode and failure type,the data were screened and divided into seven categories.The results of the database were compared with those of the corresponding shear capacity formula in the Technical specification for concrete structures of tall buildings(JGJ 3—2010).The results show that for barbell-shaped or flanged reinforced concrete walls,the ratios of the measured shear capacity to the calculated shear capacity by shear capacity formula are discrete.For diagonal tension failure formulas under permanent and transient design conditions,the shear capacity formula of steel bar part are inaccurate,which results in the whole diagonal tension failure formula.While for diagonal tension failure formulas under seismic design conditions,shear capacity formula of concrete part are inaccurate,which results in the decreased inaccurate calculation results of the whole diagonal tension failure formula.Based on the experimental database,three kinds of formulas were revised to make the calculation results conform to the experimental law,including the shear capacity formula of steel bar part under permanent and transient design conditions,shear capacity formula of concrete part under seismic design conditions and diagonal compression formula of components with shear-span ratio of no more than 2.5.A revised formula for calculating the shear capacity of barbell-shaped or flanged reinforced concrete walls was given.The comparison between the calculated and measured values shows that the revised formula is accurate.