Space miner blast5/16/2023 ![]() The rapid expansions of gases in the hole can create pressures reaching a maximum of 100,000 atmospheres and occurs within milliseconds (USACE 1972). This process is fairly complicated but can be broken into three main components: initial pressure buildup, wave transmission and air blast (USACE 1972). The basic principle behind rock blasting is the release of energy from a chemical compound, the explosive, in the form of expansive gases and heat inside a hole drilled into a relatively concentrated part of the rock mass. Finally, the damages associated with blasting will be summarized before the specific case histories are evaluated. Additionally, the typical terms and components of a blast will be outlined. The mechanics of rock blasting and the uses of blasting, some of which were listed previously, will be discussed. Therefore, preceding the discussion on blast mitigation is a general overview of surface blasting. Understanding of the damages resulting from blasting must stem from knowledge of blasting itself. As the use of blasting progressed, however, how to blast became better documented in manuals and textbooks to move blasting away from rules of thumb into a more scientific method, and with this progression, ways to limit the extent of damage by using certain techniques, such as presplit and smooth blasting. ![]() Like many procedures that are centuries old, blasting was once simply done by intuition and experience. Damages can be considered loss of strength to the remaining rock mass in which the blasting occurs. ![]() For the extent of this paper, the discussion of damages will be limited to a general sense and two specific case histories, the Ekati Mine in Canada and the excavation of high rock slopes in China. Rock blasting has been used in mining for hundreds of years and continues up to this day, but other uses, like excavation of rock slopes for highways through mountains or the preparation of rock for the foundations of buildings, has grown considerably within the last century.Īs blasting has become more extensive, the damages caused have grown as well. Blasting, however, utilizes explosives in a constructive way by focusing the vast energy produced by the explosion towards breaking rock masses into more manageable fragment sizes, while simultaneously mitigating the damages caused by the explosions to other structures or permanent rock masses. Explosives have been used by humans as an effective tool since ancient times, typically in the art of war. ![]()
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