In order to study the stability of the high and steep slope of an open-pit mine under deep bench blasting vibration, a mine in Inner Mongolia is taken as the engineering background, and the mechanical parameters of rock samples were determined based on uniaxial and triaxial instruments. The stability of the high and steep slope of the open-pit mine under static and dynamic loads was analyzed by using field vibration monitoring and numerical simulation methods. The results show that the vibration range of the vibration wave is -1.25–1.25 cm/s, and the vibration wave shows a gradual attenuation trend. The Sadovsky regression equation was used to analyze and fit the monitoring data and the corresponding regression equations in each direction were obtained. Under static action, the safety factor of the high and steep slope is 1.20, and the displacement of the sliding zone passing through the slope is small, so the slope stability is good. Under the action of dynamic blasting load, the overall displacement of the slope is small, and the change of displacement decreases with the decrease of the vibration wave.

The modifying effects of polymer on bitumen low-temperature performance are substantially compromised by the thermal breakdown of styrene–butadiene rubber (SBR) polymer during bitumen mixture production operations. The efficacy of the utilization of Sasobit/waste cooking oil (Sasobit/WCO) as a warm-mix additive has been demonstrated in mitigating the adverse consequences of thermal aging on SBR-modified bitumen binder (SB) while preserving the binder’s original performance characteristics. However, few studies have been conducted to further investigate the rheological properties and aging resistance of SB modified with Sasobit/WCO compounds. In this work, three additives—Sasobit, WCO, and Sasobit/WCO composite—were selected, and their effects on the physical and rheological characteristics of SB as well as the temperatures at which the mixtures were prepared were assessed. In addition, by using dynamic shear rheometers (DSR) and bending beam rheometers (BBR), the effects of this innovative warm-mix addition on the performance grade (PG) and aging resistances of SB were evaluated. According to the results, Sasobit/WCO composites outperform Sasobit and WCO in lowering the mixture preparation temperature. Sasobit/WCO also improves both the high- and low-temperature performance of SB simultaneously. Compared to hot-mix asphalt mixtures, the addition of Sasobit/WCO reduces the preparation temperature of the bitumen mixtures by 19 °C, which in turn helps to minimize the negative effects of temperature aging on the functioning of the SB. Additionally, the Sasobit/WCO composite addition can improve the SB mixture’s resistance to thermal cracking. After the introduction of Sasobit/WCO, the high-temperature PG of SB was raised by two levels, regardless of whether the warm-mix impact was taken into account. With the addition of Sasobit/WCO, SB’s resilience to short-term aging was enhanced.

The strip structure filling mining technology is suggested in response to the environmental issues such as surface subsidence and landslides brought on by the mining of 11,071 working faces in a mine in Guizhou. The mining technology system is studied through indoor testing, numerical simulation, and engineering monitoring. According to theoretical study, the filling strip can be steadily loaded and its value doesn't exceed 10 m when the width of the filling strip and the width of the filling interval are set to be equal. According to laboratory testing, fly ash can replace some of the cement in the cement mixture as a binder to maintain strength while cutting costs. The degree of crystallization gradually distributed into the network in the filling paste of various ages corresponds to its strength when combined with the findings of scanning electron microscopy; The numerical simulation results show that the maximum subsidence of the immediate roof is reduced from 340 to 3 mm from the filling rate of 0 to 100%, the filling effect is remarkable, and the shape of the settlement curve is changed from 'U' to 'basin', then to 'W'; during the local filling mining, the settlement curve of the immediate roof presents a 'wave' shape, and the stress curve of the immediate roof in the middle of the stope is also changed. The peak tension of the coal wall falls synchronously with filling spacing on both sides of the stope. The overall vertical stress below the mountain is larger, and the vertical stress at the top of the filling body eventually shifts from a "saddle" shape to a "inverted U" shape without zero support stress. In conjunction with the plastic zone, it is discovered that the stable bearing of the "filling strip-direct roof" composite structure increases with decreasing tensile and shear damage range of the hollow roof area and both sides of the top of the "filling 3 m interval 3 m" scheme; engineering measurement also reveals that the higher the position of the survey line is, the smaller the displacement is. However, the overall displacement of the strata directly above is negligible, and the greatest displacement is only 10.9 mm, which is consistent with the numerical simulation. At the same time, the displacement beneath the mountain area is too great.

In order to explore the mechanical response characteristics of fractured sandstone under true triaxial different medium principal stresses, matdem particle flow software was used to study the mechanical response characteristics, fracture mechanism and damage evolution characteristics of sandstone specimens under the conditions of 30 MPa, 40 MPa and 50 MPa respectively. The simulation results are verified by true triaxial test. The results show that under true triaxial stress, the increase of medium principal stress is beneficial to increase the strength of sandstone. The fracture degree of the specimen increases with the increase of the intermediate principal stress, and finally the interlacing macroscopic cracks are formed. When the intermediate principal stress is perpendicular to the fracture strike, the fracture mode of sandstone is that the macroscopic fracture plane is perpendicular to the fracture strike, and the fracture mechanism of sandstone under true triaxial compression is mainly shear failure, accompanied by tensile failure. With the increasing of the intermediate principal stress, the fractal dimension of the fracture of sandstone specimen increases significantly and the degree of fracture deepens. Combined with the true triaxial test results, the rationality of particle flow simulation test is proved.

According to the characteristics that the dynamic tension of rock material is elastic brittle and the dynamic compression is elastic plastic, based on previous studies, the influence of initial damage is considered in the established compression damage model, and the calculation formula of the damage threshold used to evaluate whether the surrounding rock is affected by blasting is given. According to the classic rock impact dynamic damage model and statistical damage mechanics theory, a rock compressive and tensile statistical damage constitutive model and impact damage model under blasting load is proposed. Based on the proposed damage model and the classic dynamic tensile damage model, the numerical simulation of blasting damage was carried out, and the numerical calculation results were compared with the field measurement results. Based on the established damage model, to further clarify the damage evolution characteristics of rock under blasting load, fractal dimension theory was introduced to analyze the rock damage under blasting loads with different blasting hole network parameters. The results show that compared with the axial direction of the blast hole, the direction of blast hole diameter is the main direction of blasting fracture extension. Tensile fracture mainly occurs along the hole diameter direction, and compression fracture mainly occurs below the hole bottom. Compared with the numerical calculation results based on the classical dynamic tensile damage model, the blasting fracture range obtained according to the damage model, especially the fracture depth below the bottom of the hole, was not much different from the measured value and was closest to the measured value. The crack density of 1 us, 90 aperture, and 130 aperture was larger than that of the other working conditions. Among them, the crack density of 130 aperture was the largest, followed by 90 aperture. At 2~3 us after initiation, cracks between two blast holes, radial cracks and circumferential cracks around two blast holes, and obvious cracks were formed around blastholes; at 4~5 us after initiation, the shock wave front decreased rapidly and propagated outward in the form of the compression wave. The crack propagation velocity was much smaller than that at 1~3 us after initiation. In summary, the proposed damage model is reasonable and has certain engineering practicability.

In high-stress deep mines prone to rock bursts, the significant deformation of roadway surrounding rock remains a critical scientific issue that urgently requires resolution. In this study, through theoretical analysis and numerical simulations, the failure mechanisms of different roadway sections are investigated, and the “force-center theory” is proposed. This hypothesis is validated by industrial experiments, yielding several key findings: (1) For any cross-sectional shape of the roadway, a unique peripheral circle will be formed, and the damaged area of the roadway section is mainly oriented towards the center of the peripheral circle. (2) During roadway excavation, the stress at any point on the perimeter can be decomposed into a normal stress directed towards the center and a tangential shear stress along the perimeter. The direction of the normal stress plays a crucial role in roadway failure. (3) The effectiveness of roadway reinforcement support lies in the strategic placement of anchor rods and cables along the direction of “external circular stress”. (4) When the external circular method was applied in the high-stress environment of the third soft coal seam in Zhongheng Coal Mine, remarkable results were achieved. The roof-to-floor convergence decreased by 80.34%, and the daily convergence rate decreased by 83.81% accordingly. Additionally, the side convergence decreased by 59.96%, with a 67.50% reduction in the daily rate. This hypothesis provides precise theoretical underpinnings and practical guidance for addressing crucial issues such as the optimal design of roadway sections, the limitations of bolt support schemes (especially in terms of bolt installation angles), and the strategic layout of reinforcement holes.