SBIR Phase II: Controlled Foam Injection for the Fracturing of Rock and Concrete

这个小型企业创新研究第二阶段项目旨在研究和改进新的非爆炸性岩石挖掘和混凝土拆除方法。该方法包括将高压泡沫注入岩石或混凝土中的预钻孔中，通过结合新的孔底密封方法的桶进行破碎。泡沫的高粘度（与气体相比）与其储能特性（与液体相比）相结合导致非常受控的破裂。第一阶段的计划表明，该方法可以始终打破岩石或混凝土的压力一个数量级低于爆炸或推进剂为基础的方法。气爆和飞石被减少到非常良性的水平，允许该方法以连续的方式应用，并用于城市和其他敏感环境。该方法的增量中断与所需硬件的简单性相结合，使得该方法高度适合于自动化。第二阶段项目将研究泡沫配方，以进一步提高该方法的效率，改进封孔方法，实现钻孔和破碎周期的自动化，并将该技术与其他采矿和隧道作业（如出渣和地面控制）相结合。 用于岩石破碎的受控泡沫注入方法可以在基础设施开发和维护中有许多应用。该方法对于在现有街道和建筑物下开发公用事业隧道，为现有地铁系统提供通道隧道或竖井，修改隧道掘进机产生的圆孔或为建筑物挖掘地下空间是理想的。在混凝土破碎和剥离领域，当排除爆炸方法或需要建筑物或结构部件的抢救和回收时，该方法可用于拆除混凝土结构。

This Small Business Innovation Research Phase II project is directed towards the study and refinement of anew non-explosive rock excavation and concrete demolition method. The method involves injecting high-pressure foam into pre-drilled holes in the rock or concrete to be broken through a barrel incorporating a new hole bottom sealing method. The high viscosity of the foam (as compared to a gas) combined with its stored energy characteristics (as compared to a liquid) result in very controlled breakage. The Phase I program demonstrated that the method can consistently break rock or concrete at pressures an order of magnitude less than in explosive or propellant based methods. Airblast and flyrock are reduced to very benign levels allowing the method to be applied in a continuous manner and to be used in urban and other sensitive environments. The incremental breakage of the method combined with the simplicity of the requisite hardware make the method highly amenable to automation. The Phase II project will investigate foam formulations to further improve the efficiency of the method, improved hole sealing methods, automation of the drill and break cycle, and integration of the technology with other mining and tunneling operations, such as mucking and ground control. The controlled foam injection method for rock breakage could have many applications in infrastructure development and maintenance. The method would be ideal for developing utility tunnels under existing streets and buildings, providing access tunnels or shafts to existing subway systems, modifying the round bores produced by tunnel boring machines or excavating underground space for buildings. In the area of concrete breakage and stripping the method would be useful for demolishing concrete structures when explosive methods were precluded or where salvage and recycling of building or structure components are desirable.