Montmorillonite is an important layered phyllosilicate material with many useful physicochemical and mechanical properties, which is widely used in medicine, environmental protection, construction industry, and other fields. In order to a get better understanding of the behavior of montmorillonite under high pressure, we studied its atomic structure, electronic and mechanical properties using density functional theory (DFT), including dispersion corrections, as function of the interlayer Na and Mg cations. At ideal condition, the calculations of lattice constants, bond length, band structure, and elastic modulus of Na- and Mg-montmorillonite are in good agreement with the experimental values. Under high pressure, the lattice constants and major bond lengths decreased with increasing pressure. The calculated electronic properties and band structure show only a slight change under 20 GPa, indicating that the effect of pressure on the electronic properties of Na- and Mg-montmorillonite is weak. The bulk modulus, shear modulus, Young’s modulus, shear wave velocity and compression wave velocity of Na- and Mg-montmorillonite are positively correlated with the external pressure, and the other mechanical parameters have a little change. The calculated studies will be useful to explore experiments in the future from a purely scientific point of view.

Anchor cable failures due to dynamic loads are common in rock engineering. Traditional cables could be invalid to accommodate large displacement and deformation in geomaterials. Cable body failure often occurs due to limitations in mechanical characteristics and small deformation of traditional anchor cables. The new Negative Poisson’s ratio (NPR) cable has the mechanical properties of high strength, toughness, and impact resistance due to its special structure. This study investigated the response of NPR cable anchorage systems under dynamic loading through laboratory tests and numerical modeling. The dynamic pull-out tests on NPR cable under drop hammer loading were conducted to examine the behavior of dynamic perturbation mitigation. To investigate the intricate NPR cable-rock interaction, a coupled model utilizing the distinct element method (DEM) and the finite difference method (FDM) was established. The NPR cable was encircled by grouted concrete and sandstone modeled with discretized particles using the distinct element method. The numerical results and the NPR cable-rock interaction under dynamic loading were carefully analyzed and discussed. The NPR cable-rock interaction, including the relative sliding displacement between the cone and the pipe, the accumulated relative sliding displacement between the cone and the pipe, the radial displacement of the pipe, and the contact forces of concrete and rock, were carefully studied through numerical simulation. Furthermore, a microscopic analysis was conducted to investigate the failure modes exhibited by the grouting material and the surrounding rock. Finally, NPR cables are utilized to reinforce the slope stability in open-pit mines. Their applications demonstrate that NPR cables can mitigate slope failures and play a crucial role in anticipating and providing timely warnings of slope instability, alongside a comprehensive slope stability monitoring system. This study offers valuable insights that can contribute to predicting and enhancing the performance of NPR cables in mitigating the effects of dynamic disasters.

A “random-type” sand–concrete interface shear test was developed based on the sand cone method, with a focus on the most commonly encountered triangular contact surface morphology. A “regular-type” triangular interface, matched in roughness to the “random-type”, was meticulously designed. This “regular-type” interface features five distinct triangular groove inclinations: 18°, 33°, 50°, 70°, and 90°. A series of sand–concrete interface direct shear tests were conducted under consistent compaction conditions to investigate the impact of varying compaction densities and triangular groove inclinations on the shear strength at the interface. Particle flow simulations were utilized to examine the morphology of the shear band and the characteristics of particle migration influenced by the triangular contact surface. This analysis is aimed at elucidating the influence of the inclination of the triangular groove on the shear failure mechanism at the sand–concrete interface. The findings indicate that: (1) The morphology of the interface significantly impacts the shear strength of the sand–concrete interface, while the shape of the stress-displacement curve experiences minimal alteration. (2) At smaller inclination angles, particle contact forces are arranged in a wave-like configuration around the sawtooth tip, resulting in a non-uniform stress distribution along the sawtooth slope. However, as the inclination angle grows, the stress concentration at the sawtooth tip diminishes, and the stress distribution across the sawtooth slope becomes more consistent. (3) Particle migration is significantly influenced by the sawtooth’s inclination angle. At lower angles, particles climb the structure’s tip through sliding and rolling. As the angle increases, particle motion shifts to shear, accompanied by a transition in friction from surface friction to internal shear friction. This leads to the formation of a wider shear band and an increase in shear strength.