The relationship between storage-dissipation-release of coal energy and intensity of induced charge

Abstract

Using uniaxial compression experiments, the evolution characteristics between energy and induced charge in each stage of coal deformation and failure are studied. Further, the relationship of energy conversion in the process of coal failure is analyzed. The calculation methods of energy storage, dissipation, and release of coal are proposed. The relationships between induced charge intensity and factors, including storage of elastic strain energy, increment of elastic strain energy, increment of dissipated energy, released energy, accumulated dissipated-released energy, are studied. A theoretical model of induced charge based on dissipated energy and released energy is established. The monitoring test of induced charge under the mine is conduced. The results show that the induced charge intensity is not related to the accumulation of elastic strain energy, but positively correlated to the dissipation and release of elastic strain energy. The induced charge intensity is not significantly correlated with the cumulative dissipated-released energy, but is significantly correlated with the slope of the cumulative dissipated-released energy curve and its variations. Especially when the escalation effect shows, the induced charge intensity accordingly increases in an abrupt manner. When the increment of dissipated energy rises to a certain degree, the intensity of induced charge suddenly increases. When the released energy suddenly increases, if the major part converts into the kinetic energy of coal chips and particles, a violent ejection phenomenon occurs, the induced charge intensity suddenly increases. The induced charge intensity is positively correlated with the increment of dissipated energy and the sudden increase of released energy. The higher the stress concentration degree and the greater the influence of mining for coal-rock, the larger amount of energy is dissipated and released, and thus the greater intensity of induced charge is monitored. The study can provide a theoretical basis for the monitoring and early warning of coal-rock dynamic disaster.