A high-precision and user-friendly triaxial apparatus for the measurement of permeability of gassy coal

Abstract

The calculation method of coal seam gas permeability is the key starting point for studying a series of mine safety issues. However, the existing apparatuses are complex in operation, inconvenient in sample replacement, single in function, inaccurate in deformation measurement and poor in sealing effect. In this paper, a high-precision and user-friendly triaxial apparatus is developed. The apparatus consists of triaxial pressure and deformation measurement unit, gas filling and control unit, hydraulic loading unit and flow control and acquisition unit. The apparatus has excellent sealing performance and can accurately measure the axial and circumferential deformation of the sample simultaneously. In addition, the apparatus is user-friendly and integrated with the rapid replacement of the sample module. The permeability test of gassy coal in the whole process of deformation and failure is carried out and the results are consistent with previous research results, which proves the validity and reliability of the apparatus.