非连续级配再生粗骨料自密实混凝土梁受力性能试验研究

Experimental study on mechanical behavior of self-compacting concrete beams with discontinuous graded recycled coarse aggregate

为了研究非连续级配自密实再生混凝土梁的受力性能,设计并制作了6根非连续级配自密实再生混凝土梁试件,并对其进行静力单调加载试验,观察不同再生骨料取代率下不同强度非连续级配自密实再生混凝土梁的破坏过程及破坏形态,绘制出荷载-变形、荷载-应变等关系曲线,分析了再生粗骨料取代率对试件极限承载力的影响;采用规范公式计算试件极限承载力和刚度并与试验值进行对比分析。结果表明:非连续级配自密实再生混凝土梁与普通混凝土梁的破坏过程和形态相似;再生粗骨料取代率对于最终跨中挠度的大小并没有明显的影响;混凝土规范方法可适用于非连续级配自密实再生混凝土梁的极限承载力及短期刚度计算。

In order to reveal the mechanical behavior of self-compacting recycled concrete beams with discontinuous graded recycled coarse aggregate,6 specimens were designed for the test. And the static monotonous loading test was carried out to observe the failure process and failure modes of the non-continuous gradation self-compacted concrete beams with different intensities under different replacement rates. The load-deformation and load-strain curves were analyzed. The effect of the rate of coarse aggregate substitution on the ultimate bearing capacity of the specimen was studied. The ultimate bearing capacity and stiffness of the specimen were calculated by the canonical formula and compared with the experimental values.The results show that the failure process and mode of recycled coarse aggregate is similar to that of ordinary concrete beams.The replacement rate of recycled coarse aggregate has no obvious effect on the size of the final mid-span deflection. The current concrete method can be applied to the discontinuous gradation calculation of ultimate bearing capacity and short-term stiffness of self-compacting recycled concrete beams.