再生骨料混凝土梁抗剪性能试验研究

通过8根再生混凝土有腹筋梁和4根普通混凝土有腹筋梁的对比试验,研究了再生混凝土梁斜截面的破坏形态、斜向开裂荷载和抗剪承载力.结果表明:再生混凝土抗压强度、梁的剪跨比和配箍率等因素影响再生混凝土梁的抗剪性能,再生混凝土梁的斜向开裂荷载比普通混凝土梁低6%~20%;在配箍率相对较高的情况下,再生混凝土梁的抗剪承载力与普通混凝土梁相差不大;配箍率偏小时,抗剪承载力相差较大,幅度达23%;再生混凝土梁的抗剪承载力随着剪跨比的增大而减小.根据试验结果,拟合出再生混凝土梁斜向开裂荷载以及抗剪承载力计算表达式.

Experimental study on shear behavior of recycled aggregate concrete beams

Based on comparative tests of eight recycled aggregate concrete beams and four ordinary concrete beams with stirrups, the failure modes, inclined loads and shear bearing capacity of a diagonal section of the recycled concrete beams were investigated. The results show that the compressive strength of the recycled concrete, the shear span-to-depth ratio of the beams, and the reinforcement ratio of the stirrups all have effects on the shear behavior of the recycled concrete beams. The inclined loads of the recycled aggregate concrete beams were lower than those of natural aggregate concrete beams. The shear bearing capacity of recycled concrete beams was 6%-20% lower than those of the ordinary concrete beams. With a relatively high reinforcement ratio of the stirrups, the shear bearing capacity of the recycled concrete beams was close to that of the ordinary concrete beams; with a relatively low reinforcement ratio of the stirrups, the difference of the shear bearing capacity between them was larger, up to 23%. The shear bearing capacity of the recycled concrete beams decreases with the increase of the shear span-to-depth ratio of the beams. According to the test results, the expressions for the inclined loads and the shear bearing capacity of the recycled concrete beams with stirrups are proposed.