Laboratory study on the dynamic response of rock under blast loading with active confining pressure
Laboratory study on the dynamic response of rock under blast loading with active confining pressure
复制标题
主动围压爆炸荷载作用下岩石动力响应室内研究
DOI：
10.1016/j.ijrmms.2018.01.011
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发表时间：
2018-02-01
影响因子：
7.2
通讯作者：
Yu, Qi
中科院分区：
文献类型：
--
作者：
He, Chenglong;Yang, Jun;Yu, Qi
近年来，钻爆法在深部采矿和地下结构作业中得到了广泛的应用。与地表岩石不同，地下岩石具有高地应力、高温和高孔隙压力状态。例如，在1000 m深度处，垂直原地应力可高达27 MPa，水平原地应力可约为13.5 MPa。已有的研究表明，高地应力对岩石在爆炸荷载作用下的破坏强度和动态裂纹扩展有很大的影响。1、2在围压和爆炸荷载的共同作用下，岩石的动力响应变得更加复杂，并受多种因素的控制，特别是不同K值的围压（围压的水平部分和垂直部分之比）。本文研究了柱状装药爆炸荷载的衰减过程，以及炸药、岩石材料和耦合介质的性质对岩石在爆炸荷载作用下的动力响应的影响。爆炸荷载一般由冲击波和爆炸气体组成，两者对岩石的动力响应都有重要影响。3、4最初产生高冲击波，并迅速传播到孔壁，在极高压力下因剪切带互连而出现微裂纹，导致靠近炮孔的区域被压碎和粉化。然后，周向拉伸应力随后是压缩应力波在现有缺陷中发展或产生新的径向裂纹。损伤在边界区通过反射波进一步扩展。最后由于后续的爆炸气体流入裂纹中，原始裂纹贯穿试件。五、六、七、八、九、十、十一、十二
In recent years, the method of drilling and blasting has been widely used in deep mining and underground structure operations. Unlike surface rock, underground rock has high in-situ stress, high temperature and high pore pressure state. For instance, the vertical in-situ stress can be as high 27 MPa at a depth of 1000 m, and the horizontal in-situ stress can be approximately 13.5 MPa. Previous research has indicated that high in-situ stress has a strongly effects on the failure strength and dynamic crack propagation of rock under blast loading. 1, 2 With the combined effect of confining pressures and blast loading, the dynamic response of rock becomes more complicated and is controlled by many factors, especially the confining pressure with different K (the ratio of the horizontal and vertical parts of the confining pressure). Consequently, studying the dynamic behavior of rock under in-situ stress and blasting is essential.The attenuation process of blast loading from cylindrical charges has been investigated, and the properties of the explosive, rock materials and coupling media influence the dynamic response of rock subjected to blast loading. Generally, the explosion loading consists of shock waves and explosion gases, both of which contribute significantly to the dynamic response of rock. 3, 4 High shock waves are generated initially and quickly spread to the borehole wall, and micro cracks appear due to shear band interconnection under extremely high pressures; as a result, the zone close to the blast hole is crushed and pulverized. Then, circumferential tensile stress followed by a compressive stress wave develops in the existing flaws or creates new radial cracks. The damage further extends by reflected waves in the boundary zone. Finally original cracks run through the specimen due to the subsequent explosion gas flow into cracks. 5, 6, 7, 8, 9, 10, 11, 12