Analysis of failure of coal under tri-axial compression and inversion of its shear strength parameters
HAO Xianjie
YUAN Liang
WANG Fei
ZHAO Yixin
LU Zhiguo
REN Bo
Abstract：Based on the concept of the equivalent rupture angle,according to the orthogonal analysis theory,the shear deformation and failure rules and its main influence factors of coal samples were analyzed.The results show that there are four failure modes for coal samples.Along with the decrease of the internal friction angle and the confining pressure,the order of them that easily occurred is from single shear failure,conjugate failure,shear-tension failure to ductile failure.The failure angle decreases with the increase of the internal friction angle and the confining pressure and increases with the increase of the dilatancy angle.When the friction angle is 45°,single shear damage always happen and when it is 15°,ductile failure is appeared.The method of the inversion of the cohesive force and the internal friction angle of coal samples can used to obtain mechanical parameter of a single coal sample via the peak strength、the equivalent damage angle、the peak value of axial strain and the peak value of circumferential strain.The results are in conformity with the measured values and could better reflect the disperse characteristics of coal samples.
Keywords：Tri-axial compressioncoalshear strength parametersfailure angle
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 730-738 )