Energy evolution and mechanical properties of modified magnesium slag-based backfill materials at different curing temperatures

To study the mechanical properties and failure characteristics of all-solid waste cementitious materials prepared in the intense geothermal environment of deep mines. Uniaxial compression, acoustic emission (AE), SEM and other tests were adopted to characterize the energy and deformation failure of backfill materials from different temperatures (20 degrees C, 30 degrees C, 40 degrees C). The results show that the temperature has a promoting effect on the development of modified magnesium slag-fly ash cemented paste backfill (MFPB) strength. The elastic strain energy and the dissipated energy corresponding to the peak stress increase as the curing temperature increases. The high frequency phase of the energy scatter plot is accompanied by a rapid increase in the cumulative ringing count and cumulative energy. Tensile cracks increase with the increase of curing temperature. The temperature effectively promotes the hydration process of MFPB. The decrease of strength in the later stage of curing temperature 40 degrees C is due to the harmful thermal stress within the backfill. The results provide theoretical guidance for the practical application of MFPB.