Evaluation index of bursting liability of coal based on energy transfer efficiency

Abstract

The accumulation and release of energy in coal are closely linked to rock burst, with energy transfer being a key parameter for evaluating bursting liability. This study constructs an energy transfer model under energy source disturbance conditions, where we establish a relationship between impact energy index and elastic energy index, propose the proportion of energy φ, introduce the concept of energy transfer efficiency β based on an energy dissipation model during the transfer process, develop an evaluation method for bursting liability by multiplying two efficiency parameters η=βφ. We conducted experiments to identify bursting liability of 11 coal layers from 3 pairs of coal mines, whose reliability was verified by referencing results from 79 layered impact tendency identifications in other coal mines. Results show that 1)the proportion of energy release φ has boundary conditions with physical significance for ground pressure; 2)there is negative correlation between the efficiency β and Poisson's ratio which can model boundary conditions; 3)calculation results of the energy transfer index η show high consistency(88.61 %)with bursting liability identification results, reflecting the bursting liability of coal bodies. It can serve as a basis for evaluating "*" outcomes and is an effective indicator suitable for existing systems used to evaluate bursting liability.

Keywords

• identification of bursting liability
• energy release ratio
• energy transfer efficiency
• energy transfer index
• rock burst