爆炸冲击作用下岩石损伤规律及对爆破效果影响的研究

发布时间：2018-06-15 02:08

本文选题：爆炸冲击 + 损伤　；参考：《西南科技大学》2015年硕士论文

【摘要】：随着社会经济发展的需要和工业原材料的需求,矿产资源已经成为不可或缺的物质基础,并且伴随着需求量的日益增加,矿产资源的需求量也随之大幅增涨。采矿业为国民经济做出了巨大贡献,但目前矿山工程爆破方面仍面临着较大的压力和挑战,矿山爆破生产中亟需提高爆破质量和爆破效果,因此通过理论和试验研究爆破效果的改善和优化具有重大的意义。本文首先通过对不同抵抗线的岩石试件进行不堵塞爆炸试验,利用声波测试及CT成像技术,研究了岩石在爆炸冲击荷载作用下的损伤规律。试验结果表明,岩石径向爆炸冲击损伤以炮孔为中心向四周衰减,衰减率随岩石到爆点中心的距离增加呈非线性降低,距炮孔中心位置3倍孔径内岩石损伤降低迅速,3倍孔径外损伤降低缓慢;炮孔轴向损伤随岩石距装药中心位置距离增加呈降低的趋势,刚开始降低梯度较大,后随着距离增大梯度趋于平缓;不同抵抗线距离起爆的岩石试件炮孔轴向和径向受到的爆炸冲击损伤存在着差异。其次通过不同损伤度岩石试件的单轴抗压试验,研究了损伤岩石的力学性能,得出岩石峰值应力随损伤度的增加而降低,且降低率随损伤度增加逐渐增大;对损伤岩石峰值前应力应变曲线采用多项式进行拟合,并在此基础上得出了岩石损伤本构关系表达式。最后进行了岩石在不同损伤状况下的爆破试验,研究了岩石爆炸冲击损伤对爆破效果的影响规律。试验得出,不同抵抗线距离起爆的岩石试件受到的爆炸冲击损伤不同,抵抗线小的岩石试件受到的爆炸冲击损伤较大,爆破效果更好。本研究得出了岩石在爆炸冲击作用下的损伤规律,得出了爆炸冲击作用下岩石损伤本构关系,得到了岩石爆炸冲击损伤对爆破效果的影响规律,为优化矿山爆破参数、改善爆破效果和提高爆破质量提供了参考。
[Abstract]:With the development of social economy and the demand of industrial raw materials, mineral resources have become an indispensable material basis, and with the increasing demand, the demand for mineral resources has also increased substantially. The mining industry has made great contributions to the national economy, but at present, the mine engineering blasting is still faced with great pressure and challenge. It is urgent to improve the blasting quality and blasting effect in the mine blasting production. Therefore, it is of great significance to study the improvement and optimization of blasting effect through theory and experiment. In this paper, the damage law of rock subjected to blast shock loading is studied by means of acoustic wave test and CT imaging technique by means of non-clogging explosion test of rock specimens with different resistance lines. The experimental results show that the radial blast impact damage of rock attenuates around the center of the hole, and the attenuation rate decreases with the increase of the distance between the rock and the center of the blasting point. The damage of rock decreases rapidly by 3 times pore diameter from the center of the hole and decreases slowly with the increase of the distance from the center of the hole to the center of the charge, and the gradient is larger at the beginning of the decrease of the axial damage of the hole with the increase of the distance from the center of the rock to the charge center. The gradient tends to be gentle with the increase of distance, and there are differences in the axial and radial impact damage of the blasting holes of rock specimens with different resistance line distances. Secondly, through uniaxial compression test of rock specimens with different damage degree, the mechanical properties of damaged rock are studied. It is concluded that the peak stress of rock decreases with the increase of damage degree, and the decreasing rate increases gradually with the increase of damage degree. The stress-strain curve before peak value of damaged rock is fitted by polynomial, and the constitutive expression of rock damage is obtained. Finally, the blasting test of rock under different damage conditions was carried out, and the effect of rock blast impact damage on blasting effect was studied. The experimental results show that rock specimens with different distance of resistance line are affected by different blast impact damage, and rock specimens with small resistance line are damaged more by explosion impact, and the blasting effect is better than that of rock specimen with small resistance line. In this study, the damage law of rock under explosion shock is obtained, the constitutive relation of rock damage under explosion shock is obtained, and the influence law of rock explosion impact damage on blasting effect is obtained, so as to optimize the blasting parameters of mine. A reference is provided to improve the blasting effect and the blasting quality.
【学位授予单位】：西南科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD235

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