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High performance concrete (HPC) has the characteristics of high strength, high brittleness and low toughness, so it can not be widely used in engineering field. The rubber particles themselves have good elasticity and excellent wear resistance. To this end, rubber particles were used to prepare high performance rubber concrete (HPRC) instead of fine aggregate, and compressive strength and splitting tensile strength tests were carried out according to standard test methods. These data were evaluated, and it was found that adding different mesh number (10 mesh, 20 mesh, 30 mesh) and different content (10%, 20%, 30%) of rubber particles reduced the compressive and tensile properties of high-performance rubber concrete to different degrees. The rubber particles with l size of 30 mesh and content of 10% have the least influence on the mechanical properties of high-performance rubber concrete, and the compressive strength and tensile strength of HPC 28 days only decrease by 18.19% and 5.56%, respectively. From the damage form, the addition of rubber particles makes the high performance concrete change from brittle to ductile. The research shows that recycling rubber from waste tires into concrete manufacturing is an environmentally friendly and feasible waste management strategy. These results have the potential to replace concrete in construction and promote sustainable growth.

The mechanical behavior of splitting tensile damage and the law of stress wave propagation of rock-like materials (RLM) are of great significance to further reveal the dynamic disaster mechanism of the deep rock mass. The meso-damage mechanical behavior and stress wave propagation characteristics of RLM disks under impact splitting were studied by using a large diameter split Hopkinson pressure bar (SHPB). In terms of dynamic damage, the splitting tensile stress-compression strain curves of RLM disks obviously showed three stages of mechanical behavior evolution: initial elastic-plastic deformation, pre-peak plastic damage, and post-peak brittle fracture failure. The macro-damage of RLM disks increased with the increase of strain rate. The meso-tensile fracture was the result of both the initial meso-damage and the impact splitting meso-damage. The dynamic splitting damage variable defined based on the damage fracture energy can accurately describe the damage evolution characteristics of impact splitting on RLM disks. In the aspect of stress wave propagation, the peak value of transmission stress showed an advanced effect with the increase of incident stress wave. In the early stage (0–50 μs), the transmission stress wave ratio (σT/σI) increased with the increase of strain rate, while in the later stage (82–200 μs), the transmission stress wave ratio (σT/σI) decreased with the increase of strain rate. The stress wave propagation law in the process of impact splitting on RLM disks was clearly revealed based on the stress wave propagation model established by the one-dimensional elastic stress wave theory. Finally, the dynamic mechanical mechanism of splitting damage and fracture of RLM disks under different strain rates was discussed deeply.

In this study, through a series of static mechanical tests and split Hopkinson pressure bar (SHPB) dynamic impact tests, the static and dynamic mechanical parameters of yellow sandstone are determined, and the Holmquist–Johnson–Cook model parameters of the rock are determined by the test data and theoretical calculation. The feasibility of a numerical model is verified, based on which the SHPB impact process under different axial pressure is subjected to numerical analysis. The results show that with increasing impact load, the degree of rock breakage increases, and the dynamic compressive strength and dynamic elastic modulus increase continuously. With the application and increase of axial pressure, the dynamic compressive strength and dynamic elastic modulus of the rock decrease gradually under the same impact load, and the maximum cumulative strain keeps increasing, indicating that under the influence of axial pressure, micro-cracks in the rock have initially developed and expanded. With increasing axial pressure, the rock is more vulnerable to breakage, and its weakening degree keeps increasing. The energy utilization rate of one-dimensional dynamic and static combined loading is affected by the axial compression ratio and impact load. At low axial compression ratio, the rock has high impact resistance but high energy utilization rate; at high axial compression ratio, the rock has low impact resistance but low energy utilization rate. Therefore, the combination of axial compression ratio and impact velocity can improve the crushing effect and energy utilization rate on the premise of clear crushing form requirements.