花岗岩在微波照射下的损伤研究

基于采用微波能量预先弱化岩石的方法可以有效的降低岩石强度这一理论。本文先通过对花岗岩试件进行一定条件下的微波照射及劈裂试验,再利用ANSYS软件建立简化的二相岩石模型,模拟不同功率密度和照射时间下模型内部的温度分布和应力分布。结果表明：一定功率下,随着微波照射时间的增加,花岗岩试件抗拉强度逐渐降低,降低速度先快后慢,存在一个最佳照射时间范围。而采用高功率密度和短时间的微波照射时,模型内部的温度梯度增大,更易产生较高的温度应力,造成岩石损伤。模拟结果与试结果基本吻合,为微波辅助机械破岩技术提供一定的参考价值。

Research on Damage of Granite Induced by Microwave Irradiation

Based on the theory that rock strength can be effectively reduced by the method of pre-weakening the rock by microwave energy. In this paper, the microwave irradiation and splitting experiment of granite specimen under certain conditions are carried out firstly, then ANSYS software was used to build a simplified two-phase rock model, to simulated Temperature distribution and stress distribution in the model under different power density and irradiation time. With the increase of the time of microwave irradiation, The results showed that : tensile strength of granite specimens decreased gradually, whose decreasing velocity is fast at first then slow, there is an optimal range of irradiation time. While using high power density and short time of microwave irradiation, temperature gradients increase in the model, which is easier to produce higher temperature stress and cause damage to rock. The experimental results coincide with numerical simulation results, providing some reference value for microwave-assisted mechanical rock breaking method.