Experimental study on characteristics of acoustic emission for coal containing gas damaged evolution under loading

Abstract

An information collection system of coal containing gas under uniaxial compression was built, dates' change of acoustic emission and mechanical parameters while coal samples loaded were tested, and damaged evolution model of coal and rock and characteristic of acoustic emission were studied deeply. The research results show that there are acoustic emission signals produced during loaded process for coal containing gas. The number of acoustic emission singles is less at early stage and more at later stage, while achieves the maximum value when the load reaches peak value. The change trend of pulse number and energy of acoustic emission is consistent with the load value, which can reflect damage degree of coal containing gas well. Based on the coal damaged evolution model of acoustic emission characteristics parameters, change trend of damage value calculated from the acoustic emission pulse number and energy and the actual measured value are basical identical. As a precursor information, the acoustic emission signal can represent damage evolution laws of coal and rock and reflect damage state under loaded state. The research result would provide reference for monitoring and preventing of gas dynamic disaster of coal and rock in coal mine.

Keywords

• coal containing gas
• loaded damage
• acoustic emission characteristics
• evolution law
• mechanical parameter
• monitoring and warning