精确延时爆破控制破碎块度机理研究

本项目针对露天矿开采中爆破质量控制问题，通过理论分析、模型试验、数值模拟及现场试验等方法，系统研究利用毫秒级精确延时控制岩石破碎块度机理。基于逐孔起爆条件下台阶单孔爆破岩石的楔形破碎理论，深入开展逐孔起爆精确延时起爆的岩石破碎理论研究；借助数字图像相关方法等试验手段开展室内台阶爆破模型试验，通过分析孔间应力波传播、爆生裂纹扩展速度和裂纹扩张形态，提出逐孔起爆岩石破碎理论模型和精确延时间隔计算方法；结合有限元和流行元等数值模拟研究，进一步探索毫秒延时爆破岩石破碎块度的分布规律，建立不同岩性的精确延时逐孔起爆岩石破碎块度预测模型。通过现场爆破试验验证上述计算方法和块度预测模型，为改善露天台阶爆破质量和优化台阶爆破设计提供科学依据。

The project is aiming at controlling blasting quality in open pit mining, through theoretical analysis, model test, numerical simulation , field test, and other methods, systematic research on mechanism of utilizing millisecond precision time delay to control rock fragmentation size. On account of single hole blasting wedge theory of rock fragmentation in hole-by-hole initiation, carry out rock fragmentation theory research of per-hole initiation of precise time delay in a deep-going way. With the aid of digital image correlation method and other test means carrying out indoor bench blasting model test, by analyzing the stress wave propagation, blasting crack propagation rate and crack expansion form between the hole, present theory model of rock fragmentation and calculation method of precise time delay interval in hole-by-hole initiation. Combined with finite element and popular element numerical simulation, etc, Further exploration of rock fragmentation distribution regularity of millisecond delay blasting, establish different lithology rock fragmentation prediction model of precision time delay in hole-by-hole initiation. Through the field blasting test validates the above calculation method and prediction model, for improving the quality of the open-air bench blasting and the optimization of bench blasting design to provide the scientific basis.