粉对再生机制砂混凝土收缩和强度性能的影响研究

Study on the Influence of Stone Powder on the Shrinkage and Strength of Recycled Machine-Made Sand Concrete

废旧混凝土再生机制砂制备混凝土具有显著的经济、环保效益。本文从强度和收缩性能方面研究了石粉含量对废旧混凝土再生机制砂混凝土性能影响。结果表明:石粉含量<9%对混凝土工作性能有改善作用,并提高了混凝土抗压强度,9%石粉掺量提高混凝土抗压强度约10%。适量的石粉会降低混凝土早期自收缩,但3 d混凝土的自收缩与石粉含量之间没有明显的关联。石粉含量<6%时可抑制再生机制砂混凝土干燥收缩,研究结论对于废旧混凝土再生机制砂混凝土应用提供了借鉴。

The recycled machine-made sand concrete has significant economic and environmental benefits.In this paper,the influence of stone powder content on strength and shrinkage performance of the recycled machine-made sand concrete is studied.The results showed that the stone powder can improve the working performance and increase the compressive strength of concrete when its content is less than 9%,and 9% stone powder can increase the compressive strength of concrete by about 10%.An appropriate amount of stone powder can reduce the early self-shrinkage of concrete,but there is no obvious correlation between the self-shrinkage of 3 days concrete and the content of stone powder.When the content of stone powder is less than 6%,the dry shrinkage of recycled machine-made sand concrete can be inhibited.The research conclusions provide references for the application of recycled sand concrete.