矿物掺合料在喷射混凝土中的应用研究

Application research of mineral admixture used in shotcrete

为研究矿物掺合料在喷射混凝土中的应用效果,通过文献调研,分析了粉煤灰、硅粉、凝灰岩粉等矿物掺合料的性能特点、对混凝土性能的影响及其在喷射混凝土中的应用,并通过不同配合比的喷射混凝土试验研究,分析了凝灰岩粉对喷射混凝土性能的影响。结果表明:粉煤灰、硅粉、凝灰岩粉的掺量分别在30%,10%和15%以内时,所配制混凝土能够满足工程施工性能及强度等级要求,并可改善喷射混凝土的和易性、降低喷射回弹、细化内部孔隙结构、提升耐久性能等;复掺凝灰岩粉与粉煤灰的技术方案优于单掺,其可充分发挥两种掺合料的各自优势,综合提升喷射混凝土的施工性能与技术效果;将矿物掺合料掺入喷射混凝土中,是改善混凝土性能、降低工程成本及地缘性材料资源化利用的有效途径。研究成果可为矿物掺合料在喷射混凝土中的应用以及地缘性矿物掺合料的推广提供参考。

In order to research the application of mineral admixture used in shotcrete,through literature research,this paper analyzed the performance characteristics of mineral admixtures such as fly ash,silica fume,tuff powder,etc.,their influence on the concrete performance and their application in shotcrete.By the experiment of shotcrete with different mix proportion,The influence of tuff powder on the performance of shotcrete was studied.The results showed that when the content of fly ash,silica fume and tuff powder was within 30%,10%and 15%respectively,the engineering construction performance and strength requirements could be meet,the workability of shotcrete could be improved,the rebound of shotcrete could be reduced,the internal pore structure could be refined and the durability of the shotcrete would be improved.The technical scheme of composite admixture of tuff powder and fly ash was better than that of single admixture,which could give full play to the respective advantages of the two admixtures and comprehensively improved the construction performance and technical effect of shotcrete.The incorporation of mineral admixtures into shotcrete was an effective way to improve the performance of concrete to reduce the engineering cost and to utilize geomaterials.The research results can provide references for the application of mineral admixtures in shotcrete and the promotion of geo-mineral admixtures.