碱矿渣陶砂砂浆砌筑的砌体轴心受拉性能试验

Axial tensile performance of masonry with alkali-activated slag mortar with pottery sand

为考察碱激发矿渣陶砂砂浆砌筑的砌体轴心抗拉性能,本文完成了强度等级介于Mb20~Mb65碱激发矿渣陶砂砂浆砌筑的60个空心砌块砌体试件的轴心抗拉试验。通过在墙片端孔灌注混凝土并对锚固于端孔混凝土的水平钢筋施加轴心拉力,考察了水灰比、砂灰比、Na2O含量、水玻璃模数和碱激发矿渣陶砂砂浆抗压强度对空心砌块砌体轴心抗拉强度的影响。试验结果表明:碱激发矿渣陶砂砂浆砌筑的空心砌块砌体轴心抗拉强度随着砂浆抗压强度的增大而增大,但小于用水泥砂浆和混合砂浆砌筑的空心砌块砌体的轴心抗拉强度。基于试验结果,建立了以水灰比(介于0.44~0.53)、砂灰比(介于1.76~2.50)、Na2O含量(介于4.4%~9.3%)、水玻璃模数(介于0~1.26)和碱激发矿渣陶砂砂浆抗压强度(介于20.9~65.0MPa)为变量的空心砌块砌体轴心抗拉强度的计算公式。

The axial tensile strength of 60 hollow block masonry specimens containing Mb20-Mb65 alkali-activated slag mortar with pottery sand was investigated. Concrete was poured into the end holes of wall sheets,and axial tensile force was applied by using horizontal reinforcements anchored in the concrete of end holes. The effects of water-to-cementitous material ratio,sand-to- cementitous material ratio,Na 2O content,silicate modulus,and the compressive strength of alkali-activated slag mortar containing pottery sand on the axial tensile strength of hollow block masonry were investigated. Experimental results showed that the axial tensile strength of hollow block masonry constructed with alkali-activated slag mortar containing pottery sand increased as the compressive strength of mortar increased and was lower than that of hollow block masonry prepared with cement mortar and mixed mortar. The water-to-cementitous material ratio was between 0.44 and 0.53,the sand-to-cementitous material ratio ranged from 1.76 to 2.50,Na 2O content was between 4.4% and 9.3%,the silicate modulus was in the range of 0 and 1.26,and the compressive strength of alkali-activated slag mortar with pottery sand was between 20.9 and 65.0 MPa. The formula for the calculation of the axial tensile strength of hollow block masonry was established on the basis of the experimental results and five independent variables.