Rock breaking using conical picks is a complex process affected by several factors; its performance is directly related to the excavation rate of rock tunnels, which is important in terms of the economic benefits and social impact of a project. This study investigates the effects of cutting depth and water pressure on rock breaking performance using a conical pick assisted by an abrasive water jet (AWJ). To measure the weakening effect of the AWJ on rock strength and evaluate the practical application of this approach, further analyses of a secondary cut of rock with a fracture pit and rock breaking economy are included in this study. The results show that a conical pick can efficiently break hard rock when assisted by the strong impact of an AWJ; the cutting resistance and specific energy (SE) decrease with the use of the AWJ. With a fracture pit and surrounding tiny cracks, the cutting resistance during the secondary cut is further reduced and rock fragments become smaller. In addition, with a decrease in cutting depth and an increase in water pressure, the stability of the cutting resistance is improved, reducing conical pick costs resulting from impact fracture and wear. According to the rock breaking economy analysis of the proposed approach, there is an optimal cutting depth under certain conditions that can provide a reference for practical application.

中文翻译：

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磨料水射流辅助锥形镐破碎硬岩试验研究

使用锥形镐进行岩石破碎是一个受多种因素影响的复杂过程；其性能直接关系到岩石隧道的开挖速度，对项目的经济效益和社会影响具有重要意义。本研究使用由磨料水射流 (AWJ) 辅助的锥形截齿来研究切削深度和水压对岩石破碎性能的影响。为了测量 AWJ 对岩石强度的削弱作用并评估该方法的实际应用，本研究包括对具有裂隙坑和岩石破碎经济性的岩石二次切割的进一步分析。结果表明，在 AWJ 强力冲击的辅助下，锥形镐可以有效地破碎坚硬的岩石；使用 AWJ 时，切削阻力和比能 (SE) 会降低。裂缝坑和周围的细小裂缝，二次切削时的切削阻力进一步降低，岩石碎片变小。此外，随着切削深度的减小和水压的增加，切削阻力的稳定性得到提高，降低了因冲击断裂和磨损而导致的圆锥截齿成本。根据所提方法的破岩经济性分析，存在一定条件下的最佳切削深度，可为实际应用提供参考。减少因冲击断裂和磨损而导致的锥形截齿成本。根据所提方法的破岩经济性分析，存在一定条件下的最佳切削深度，可为实际应用提供参考。减少因冲击断裂和磨损而导致的锥形截齿成本。根据所提方法的破岩经济性分析，存在一定条件下的最佳切削深度，可为实际应用提供参考。