机制砂掺量对混凝土力学性能和体积稳定性的影响研究

Effects of manufactured sand on the mechanical properties and volume stability of concrete

通过混凝土工作性能、抗压强度、弹性模量、弯曲韧性、早期塑性开裂、干缩和徐变等试验,研究了机制砂掺量对混凝土力学性能和体积稳定性的影响。结果表明:混凝土的流变性随机制砂掺量的增加呈现减小的趋势;机制砂掺量为70%时,混凝土的力学性能和弯曲韧性最好;机制砂取代河砂有利于提高混凝土的早期抗裂性能,但是会增大干缩;机制砂掺量在40%以内对混凝土的徐变有抑制作用,掺量超过40%会增大混凝土的徐变。

Effects of manufactured sand content on the mechanical properties and volume stability of concrete were studied by testing the working performance, compressive strength,elastic modulus,flexural toughness,early age elastic crack,drying shrinkage and creep. Results show that the workability of concrete decreases with the increase of the manufactured sand dosage. Concrete with manufactured sand dosage of 70% is observed to have the optimal mechanical property and flexural toughness. The replace- ment of river sand with manufactured sand can improve the early age anti-crack ability,but increase the drying shrinkage. Within 40% replacement, inhibition effects of manufactured sand creep could be observed. When the dosage reaches above 40%,the creep is enhanced instead.