多孔混凝土的配合比设计方法及其抗冻性能

The Mixture’s Proportion Design Method and Frost Resistance of Porous Concrete

摘要: 多孔混凝土配合比设计目前没有统一的方法，针对此本文提出适合于多孔混凝土的配合比设计方法——集料逐级振实填充基础上的体积计算法；通过试验验证了实测孔隙率与目标孔隙率之间的关系；同时结合呼伦贝尔高寒的地区特点，测试了多孔混凝土的抗冻性能。研究结果表明，在确定好集料掺配比例的基础上，采用体积设计法，以目标孔隙率、集料体积、水泥浆体积三者之间的体积关系可以比较准确地对多孔混凝土的孔隙率进行设计；多孔混凝土的实测孔隙率与目标孔隙率差值仅为0.8%~2.3%，两者存在很好的线性关系。多孔混凝土的抗冻性能与实测孔隙率之间也有着良好的相关性，随着实测孔隙率的增大，其冻融循环次数在显著减小。因此，在寒冷地区，使用多孔混凝土时一定要关注其抗冻性能。

Abstract: As there is no unified method to design the mixture’s proportion of porous concrete currently, this paper brings forward the volume calculation method, which is suitable for the design method of mixture’s proportion of porous concrete based on the aggregate gradually filling. The relationships between the measured porosity and the target porosity are verified by the tests. Combined with the alpine regional characteristics in Hulunbuir, the tests of frost resistance of porous concrete are tested at the same time. The research results show that on the basis of determining the mixing proportion of aggregate, the porosity of porous concrete can be designed accurately by the volume method with the volume relationship among the target porosity, aggregates volume and cement slurry volume. The differences between the measured porosity of the porous concrete and the target porosity are only 0.8%~2.3%, and there exist a good correlation between both. Moreover, the frost resistance of porous concrete also has a positive correlation with the measured porosity. The freeze-thaw cycles significantly decreases with the increase of the measured porosity. Therefore, the frost resistance should be attention when using the porous concrete in clod area.