Developing new shotcretes

喷射混凝土是一种混凝土应用方法，在过去的30年里，无论是在混凝土修复行业还是在采矿/地面支护领域，它的使用都呈指数级增长。这种增加主要与它是一种快速干预方法有关，主要是因为它需要很少或不需要模板，并且可以应用于难以到达的区域。在维修行业，完成喷射混凝土几乎任何形状和纹理的能力也是其选择的一个重要因素。这种普及的副作用是对所生产的喷射混凝土的质量和耐久性提出了新的更严格的要求。本CRD项目的目标是研究当今喷射混凝土最敏感的一些方面，即控制和降低开裂潜力，提高特定配合比设计的绿色价值，了解和减少回弹以及超高性能喷射混凝土的发展。

Shotcrete is a concrete application method which usage has grown exponentially over the last 3 decades, both in the concrete repair industry as well as the mining/ground support field. This increase is mainly related to the fact that it is a rapid intervention method, mostly because of the fact that it requires very little or no formwork and can be applied to difficult to reach area. In the repair industry, the capacity to finish the shotcrete to nearly any kind of shape and texture has also been an important factor in its selection. The side effect of such popularity is that it has brought new and more stringent requirements on the quality and durability of the shotcrete produced. The goal of this CRD project is investigate some of the most sensitive aspects of shotcrete today, namely the control and reduction of the cracking potential, the improvement of the green value of specific mix design, the understanding and reduction of rebound and the development of ultra-high performance shotcrete. The expected outcome of the research is significant, both in terms of marketable deliverables and personnel training. The results of the project will rapidly benefit owners and Canadian society as a whole by contributing to the greater life expectancy of repaired concrete structures and cleaner and safer mining operations. Furthermore, based on these results, Canadian manufacturers of concrete construction products could optimize their existing products and develop new ones, thereby maintaining their competitiveness and strengthening their position on the international market. The proposed research venture will help prepare many highly qualified concrete engineers and scientists for an industry that is in need of a polyvalent and well-educated workforce.