摘要
为进一步改善煤体爆破效果,在岩石爆破理论基础上分析了煤体爆破作用特点与原理,确定了煤体爆破损伤断裂准则。试验结果表明:煤体中爆炸应力波一般包含两段波形,爆炸应力波的衰减速度较一般岩石更快,爆炸应力波的主要作用是形成少量新裂隙、激活原生裂隙并打破瓦斯气体的平衡状态;煤体爆破损伤包含爆炸波作用的初始阶段和爆生气体与瓦斯气体作用的后期阶段,在近区,爆破损伤以爆炸波的衰减速度迅速减小;中远区在准静态爆生气体和瓦斯气体压力作用下爆破损伤缓慢减小。LS-DYNA数值模拟结果表明,瓦斯对煤体爆破具有积极作用,瓦斯压力可以增大应力波作用时间和应力峰值。煤体爆破是爆炸应力波、爆生气体和瓦斯气体共同作用的结果。
In order to improve the coal blast effect,the anthors analyzed the coal blast characteristics,and mechanism and selected the blast fracture criteria based on the rock blast theory.The simulation experimental results show that the stress wave contains two or more waveforms,and its decay rate is faster than it in general rock.The main effect of blast stress wave is forming a small number of new cracks,activating the native fracture,and breaking the balance of coal mine gas.The blast damage includes the initial phase of blast waves and the later stage of the detonation gas and coal mine gas,near the blast area,the damage decreases rapidly,but in the moderate or far area,the main reason of damage is detonation gas and coal mine gas,the damage decreases slowly.The numerical simulation results show the coal mine gas has a positive role in the process of coal blast.The coal blast broken is the result of the roles of the blast stress wave,detonation gas and coal mine gas.
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2011年第9期1451-1456,共6页
Journal of China Coal Society
基金
国家自然科学基金资助项目(50874039
40638040)
河南省教育厅自然基金资助项目(2010B410001)
关键词
爆破机理
断裂准则
模拟试验
blast mechanism
fracture criteria
simulation experiment
