Study on the electrical impedance response and conductivity mechanism of coal mass rupture under impact load

Abstract

Studying the dynamic properties of coal is essential for safe production. This paper carries out SHPB impact load tests on coal at different velocities, innovatively realizes real-time monitoring of the impedance mode, analyses the mechanical properties and impedance mode, and finally reveals the impedance module mechanism of coal under loading. The impedance module of coal has a similar response during the rupture damage under static and dynamic loading. The increase in stress leads to enhanced electron mobility and greater electron cloud overlap between molecules, ultimately leading to a reduction in the impedance module. An abrupt increase in impedance mode results from the large self-potential generated by the massive fragmentation of the specimen. This study plays a crucial role in comprehending the damage and dynamic destruction of coal and rock under pressure, carrying significant theoretical and practical value in utilizing electrical exploration technology to predict and forecast the rock burst.