To systematically reveal the influence of laws of microwave radiation parameters (power, time) on the degradation of the mechanical properties of iron ore and the energy dissipation mechanism, and to improve the crushing efficiency of iron ore, this iron ore from Sishanling in Liaoning Province is the research object. By adopting a method combining microwave pretreatment, multi-scale mechanical tests, and microscopic tests, this thesis conducts static and dynamic impact tests as well as XRD tests on iron ore samples under different microwave actions. By analyzing the mechanical properties of iron ore subjected to various microwave treatments and utilizing the principles of energy conservation, this study elucidates the damage evolution characteristics and the laws governing energy evolution of iron ore under the coupled action of microwave and mechanical forces. The research results show that: (1) With an increase in microwave power and irradiation time, the sample mass decreases slightly, and the longitudinal wave velocity, uniaxial compressive strength, and elastic modulus exhibit a linear degradation trend. Microscopic tests have confirmed that the damage is caused by thermal stress cracking, rather than a change in composition. (2) The analysis of energy evolution indicates that microwave pretreatment diminishes the total input energy density of the sample, reduces the proportion of elastic energy, and elevates the proportion of dissipated energy. This phenomenon suggests a deterioration in the ore’s storage capacity and a transition toward plastic yielding. (3) Dynamic impact tests show that an increase in microwave damage leads to a 45.58% increase in reflected energy, a 16.12% decrease in transmitted energy, and an increase in energy dissipation to 37.49%.

This study aims to analyze the damage evolution law of the surrounding rock mass in an ultra-deep shaft under blasting load. To achieve this, a numerical simulation method is adopted based on the blasting construction practice of Xiling Auxiliary Shaft in Sanshandao Gold Mine. The simulation utilizes a restart technology based on ANSYS/LS-DYNA and adopts the equivalent explosion load method according to the blasting design scheme. The surrounding rock mass damage of the ultra-deep shaft is calculated under four different ground stresses(15 MPa, 30 MPa, 45 MPa, and 60 MPa) and four different side pressure coefficients(1.0, 1.25, 1.5, and 2.0). Furthermore, this study analyzes the damage effect on the shaft's surrounding rock mass and investigates how ground stress and side pressure coefficient influence the extent of damage to the surrounding rock. The numerical results demonstrate that as ground stress increases from 15 MPa to 60 MPa, there is a significant inhibition in the damage area with a decrease in radius from 5.75 m to 3.4 m. Additionally, it is observed that with an increase in lateral pressure coefficient, there is anisotropy in terms of blasting damage area distribution where greater ground stress leads to concentrated damage areas.

Researching blasting similar simulation materials for ultra-deep shaft surrounding rock and conducting physical model tests are the basis for studying the dynamic response law of ultra-deep shaft surrounding rock under blasting. This paper used the monzonitic granite in Xiling subsidiary shaft of Sanshandao gold mine as the simulation object to prepare similar granite materials. The iron ore powder and barite powder were selected as fine aggregates, the quartz sand was selected as coarse aggregate, the rosin alcohol solution was selected as binding material, and the gypsum was selected as adjusting material. The orthogonal design method was used to prepare the simulation materials. The mechanical parameters of similar materials with different proportions were determined, and the sensitivity analysis of each influencing factor and the blasting test of the simulated materials were carried out. The results show that the selected proportion can meet the requirements of indoor blasting model tests based on the specimen's density, unaxial compressive strength and elastic modulus. The proportion of fine aggregate in the total aggregate significantly affects the density of the simulated materials. The binder concentration significantly affects the compressive strength, tensile strength, elastic modulus and cohesion of the simulated materials. The proportion of gypsum significantly affects the internal friction angle of the simulated materials. The peak strain value in the model test block under high confining pressure is more significant as a whole, and the attenuation rate of the peak strain gradually decreases with the distance increase.