322 / 2022-03-12 15:37:42

Research on energy dissipation and electromagnetic radiation response of fractured sandstone under static and dynamic loads

Crack dip angle,Stress waves,Energy dissipation,EMR,Frequency analysis,Damage variable

（6）职业安全与健康 > 4. 矿山动力灾害防控

In order to study the energy dissipation and electromagnetic radiation (EMR) response law of fractured sandstone under dynamic and static loads, the impact dynamics experiment based on EMR test was carried out to analyze the sandstone energy dissipation and EMR change law during the failure process, and to deeply discuss the crack angle and impact velocity. The influence of the energy consumption of sample rupture and the generation mechanism of EMR. The results show that as the energy of the stress wave increases, the dissipated energy density and damage variables of the sample gradually increase, and the EMR energy also increases. With the increase of the crack inclination angle, the dissipated energy density of the sample first decreases and then increasing trend, while the damage variable and EMR energy show a trend of first increasing and then decreasing. In the process of impact damage, the main frequency of EMR is 0~5kHz. As the energy of the stress wave increases, the dominant frequency band of the main frequency expands from low frequency to high frequency, and the amplitude signal gradually increases, and α=45°specimen frequency domain relatively widest, the amplitude is also relatively largest. The inclination angle of the crack changes the failure state of the sample, resulting in a significant change in the energy dissipation of the sample and the response law of electromagnetic radiation. The electromagnetic radiation signal mainly comes from the piezoelectric effect, crack propagation and friction effect.