Research on the bearing creep characteristics and constitutive model of gangue filling body

Abstract

Abstract The creep characteristics and potential deformation regularity of the gangue backfill material are of paramount importance in backfill mining operations. This study uses crushed gangue from the Gangue Yard in Fuxin City as the research material. Utilization of an in-house designed, large scale, tri-axial gangue compaction test system. Conducting triaxial compaction creep tests on gangue materials with varying particle size distributions. An analysis is made based on different particle sizes, stresses and confinement pressures. Investigate the creep characteristics of the gangue under different conditions and explore the underlying causes. Reveal the relationship between creep deformation of gangue materials and the passage of time. Application of mathematical methods to develop a triaxial compaction creep power law model for gangue backfill materials. The results show that the main creep deformation of gangue is volume compression. The primary cause of creep deformation is the slippage and filling of pores by the finely crushed particles produced during creep fracture. At low confining pressures, the volumetric creep deformation of gangue with different particle size distributions exceeds their axial creep deformation. The external load induces stress concentration. This process involves compression, rearrangement, stress relief, adjustment and transfer of particles, which is continuously repeated and ultimately leads to deterioration and creep of the gangue. Utilization of a power function expression to elucidate the triaxial compaction creep characteristics of gangue backfill material. The established axial creep power law constitutive model and the volumetric creep power law constitutive model in double logarithmic coordinates show high applicability.