煤矿中瓦斯突出与瓦斯爆炸是危害矿业生产的“杀手”,深孔预裂爆破技术在瓦斯抽采中应用广泛,但其机理目前尚未有统一的认识。本文利用二维离散元软件中的fish语言建立了UDEC (Universal Distinct Element Code)岩体爆破模型,数值模拟计算了距爆源不同距离处岩体质点爆炸应力波的变化规律。数值模拟与理论推导结果表明:用二维离散元软件UDEC计算得到的岩体中爆炸应力波衰减规律与理论公式计算结果基本符合,误差在爆破工程应用许可的范围之内,因此UDEC适合用于数值模拟爆炸荷载下岩体的动态响应。验证了UDEC动力模块在爆炸计算中的有效性。
通过GENERATE命令划分有限差分网格,BOUNDARY xvisc和BOUNDARY yvisc设置边界条件,DAMP命令确定Rayleigh阻尼参数中的最小中心频率和最小临界阻尼比,选用高斯脉冲函数作为动力激励输入爆炸动力荷载,利用fish语言定义煤体爆破损伤本构模型,建立了UDEC煤体深孔预裂控制爆破损伤模型,得出以下结论:
1、数值计算表明煤体中爆炸应力波随径向裂隙的扩展而呈非线性衰减规律,通过曲线回归求得煤体中爆炸应力波符合指数衰减...
【英文摘要】
The coal mine gas outburst and gas explosion is damaged to the mining production. Deep hole pre-splitting blasting technology is widely used in gas extraction, but its mechanism has not been unified understanding. A dynamic numerical calculation UDEC model was set up by fish. The attenuation law of explosion stress wave in rock is simulated by the discrete element program UDEC. It is observed that numerical modeling results, on the whole, agree well with the calculated results of the deduced theoretical for...