再生粗骨料对再生混凝土性能的影响

Influence of recycled coarse aggregate on recycled concrete performance

为了研究再生粗骨料在再生混凝土中的骨架增强作用和其对再生混凝土性能的影响规律,采用试验分析的方法,通过配制不同强度的再生混凝土,分析了再生粗骨料不同的取代率和最大粒径对混凝土强度、坍落度、抗压强度和抗折强度等性能的影响。结果表明:随着再生粗骨料用量的减少,再生混凝土的抗压强度逐渐提高,抗折强度趋于增加,且抗折强度随着再生粗骨料最大粒径的增大而降低,再生粗骨料的最佳粒径为9.5mm;随着再生粗骨料掺量的增加,再生混凝土的坍落度提高。在保持混凝土配合比中的单位用水量不变的前提下,随着再生混凝土中水泥用量的减少,再生混凝土砂浆的强度也随之减小。

In order to study the skeleton improving activity of the recycled coarse aggregate in recycled concrete and the influencing laws of recycled coarse aggregate on the recycled concrete performance, experimental analysis method was adopted. Recycled concrete with different strength were prepared, and the influences of different replace quantity and maximum particle size of recycled coarse aggregate on concrete strength, slump, compressive strength and bending strength were studied. Results show that as the decrease of the content of the recycled coarse aggregate, the compressive strength of recycled concrete improves gradually, the bending strength of the recycled concrete tends to increase and reduces with the increase of the maximum particle size of recycled coarse aggregate. The best particle size of recycled coarse aggregates is 9.5mm. Along with the increase of the content of recycled aggregate, the slump of recycled concrete increases. Given the unit water use in concrete mixture ratio, the mortar strength decreases with the reduction of the cement content in recycled concrete.