煤矸石混凝土收缩性能的研究

Research on shrinkage performance of coal gangue concrete

通过煤矸石替代部分碎石、粉煤灰作为矿物掺合料研究其对混凝土收缩性能的影响,并通过优化设计方法确定复掺混凝土抗收缩性能最佳配合比。研究结果表明,随着煤矸石掺量在30%～50%、粉煤灰掺量在10%～30%范围内增加,混凝土的收缩值逐渐降低,且掺加煤矸石混凝土的收缩值低于未掺加煤矸石的混凝土收缩值。28 d混凝土收缩性能最优配合比为煤矸石替代碎石量55%,水胶比为0.44,粉煤灰掺量为35%,此时混凝土收缩应变值仅为245.845×10-6。

Crushed stone was partially replaced by gangue and fly ash was added as mineral admixtures, in which the shrinkage performance of concrete was investigated.The optimal design scheme of the resistance to shrinkage performance of composite admixture concrete was determined by optimizing design.The results show that,as the addition of gangue increased in amounts from 30%to 50%and fly ash increased from 10%to 30%, the shrinkage value of the concrete decreased by degrees.The shrinkage value of concrete added with gangue was lower than that without gangue.The mixture of optimal resistance to shrinkage of 28 d concrete was that the replacement of crushed stone by gangue was 55%,waterbinder ratio was 0.44,fly ash was 35% and correlated shrinkage value was 245.845 × 10-6.