铜丝电爆炸载荷下红砂岩破裂行为实验

Fracture behavior of red sandstone under copper wire electric explosion

金属丝电爆炸破碎岩石是一种环保且有前景的爆破技术。为进一步认识岩石在金属丝电爆炸载荷下的破裂行为,基于高压脉冲放电实验平台,开展了直铜丝电爆炸破碎红砂岩的模型实验研究。借助超高速相机观测了试件表面裂纹的起裂和扩展过程,探讨了放电电压和爆源位置等因素对岩石破裂效果的影响,具有一定的创新性。结果表明,随着放电电压增加,岩石破裂程度变得更加严重。30 kV电压下,金属丝发生电爆炸,但并未有效破裂岩石;40 kV电压下,试件出现数条宏观裂纹,红砂岩破裂成碎块状。此外,爆源到试件表面的距离越近,试件表面的裂纹越发育,试件的破碎程度越严重。

Wire electric explosion for breaking rock is a kind of environmental and promising technology.To understand the fracture behavior of rocks under wire electric explosion,this study carried out model experiments of copper wire electric explosion for breaking red sandstone by using a high voltage pulse discharges apparatus.The process of crack initiation and propagation on the surface of the specimen was observed by using an ultra-high speed camera.The effects of discharge voltage and explosion source location on the rock fracturing were analyzed.This experimental study is innovative.The experimental results show that the fracture behavior was related to the discharge voltage.Under the discharging voltage of 30 kV,the electric explosion of metal wire did not effectively break the red sandstone.However,under the discharging voltage of 40 kV,there are several macroscopic cracks in the red sandstone,and the specimen was broken into fragments.In addition,as the distance between the explosion source and the surface of the specimen decreases,the cracks on the surface become more developed and the fracture degree of red sandstone becomes more serious.