高台阶抛掷爆破机理及抛掷堆积规律研究

Height bench cast blasting is a blasting stripping method by which rocks can be thrown into the gob directly using the blasting energy without second transit. In recent years, the technique of cast blasting is widely used in dragline program, and made significant economic benefits. In the situation of study at home and abroad, the research about technique of deep-hole high bench cast blasting is not much in China, neither is theory, how to carry out effective of cast blasting, how to carry on the blasting effects forecast is short of the corresponding theoretical guidance.Project will be based on the test of casting blast, theoretical analysis, high speed photography and data statistics calculation, to analyze the affect rule for the cast blasting effects about bench height, powder factor, burden, spacing、slope angle and denseness coefficient, to study the theory of high bench cast blasting.based on the theory of dimensional analysis, based on the model test, combined with the observation of the high-speed photography to study the high bench cast blasting the distribution pattern of the velocity field of the the stepped surface rock action. With ANSYS (LS-DYNA) software on the high bench casting blast calculation and simulation of three-dimensional numerical calculation model to study the distribution and variation of the rock mass in the stress field in the high bench cast blasting.The eventual establishment of the high bench cast blasting mechanical model, to provided the theoretical basis and guidance in high bench cast blasting for the design and the effects prediction.

高台阶抛掷爆破就是利用爆破能量将剥离物直接抛掷到采空区而不需要二次搬运的爆破剥离方法。近年来，抛掷爆破技术广泛应用于倒堆剥离工艺，取得巨大的经济效益，然而，国内外关于高台阶深孔抛掷爆破机理和抛掷堆积规律研究较少，对于如何实施有效的高台阶抛掷爆破、如何进行高台阶抛掷爆破效果预测缺少相应的理论指导，本项目将依托于现场高台阶抛掷爆破试验，研究台阶高度，炸药单耗，最小抵抗线，孔距，排距、台阶坡面角及炮孔密集系数对高台阶抛掷爆破效果的影响规律，揭示高台阶抛掷爆破机理；基于量纲分析理论，以模型试验为基础，结合高速摄影的观测，研究高台阶抛掷爆破作用下台阶面岩体的速度场分布规律，借助ANSYS(LS-DYNA)软件对高台阶抛掷爆破三维数值计算模型的计算与模拟，研究在高台阶抛掷爆破作用下岩体中应力场的分布和变化规律，并最终建立高台阶抛掷爆破的力学模型，为高台阶抛掷爆破设计和效果预测提供理论依据和指导。

项目研究依托于黑岱沟露天煤矿高台阶抛掷爆破的生产实际展开，项目在量纲分析理论和相似准则指导下，建立5组共15个爆破漏斗相似模型，通过试验确定了相似材料配比，在此基础上建立相似比为1/50的高台抛掷爆破模型24个，分别研究了：炸药单耗，最小抵抗线，孔距，排距、台阶坡面角及炮孔密集系数对高台阶抛掷爆破效果的影响规律，模型试验爆破过程辅以高速摄影观测和炮孔周围应力波监测，研究高台阶抛掷爆破作用下台阶面岩体鼓包变化及速度场分布规律，建立了高台阶抛掷爆破爆堆形态预测模型，揭示了高台阶抛掷爆破机理；借助NSYS(LS-DYNA)软件对高台阶抛掷爆破三维数值计算模型的计算与模拟，研究在高台阶抛掷爆破作用下岩体中应力场的分布和变化规律，项目研究成果为高台阶抛掷爆破设计和效果预测提供了理论依据和指导。