Study on the Interaction Between Surrounding Rock and Support in High-Stress Soft Rock Roadways Based on Rock Rheological Properties

Viscoelastic solution for reinforcing tunnels with rock bolts under the coupling effect of strata rheology and stress release

During tunnel construction in weak strata, the coupled effects of ground rheological behavior and stress release significantly influence both construction progress and safety. As a critical support measure in tunneling engineering, the time-dependent mechanical interaction between rock bolts and the surrounding rock under such complex conditions remains insufficiently understood. To elucidate the time-dependent interaction mechanism between rock bolts and surrounding rock under these challenging engineering conditions, this study develops an analytical solution for bolted tunnels that explicitly couples tunnel excavation-induced stress release and ground rheology. The rheological behavior of the ground is characterized using classical Maxwell and Kelvin-Voigt creep models, while the stress release effect is represented through the virtual support pressure method. A closed-form analytical solution is ultimately derived via integral transforms. The solution accounts for two types of rock bolts: end-anchored rock bolts and fully grouted rock bolts, which are distinguished by modifying the contact conditions at the boltrock interface. Numerical simulations verify the validity and engineering applicability of the proposed analytical method. Furthermore, parametric studies are conducted to examine the influence of bolt parameters and stress release parameters on surrounding rock deformation. The proposed analytical approach provides researchers and engineers with an improved theoretical understanding of the interaction between rock bolts and tunnel surrounding rock in weak strata.

Study on Four-Dimensional Coupling Evaluation and Graded Dynamic Support Methods for Surrounding Rock Softening in High-Stress Soft Rock Roadways of Kilometer-Deep Mines

Deformation failure mechanism of deep high-stress fractured soft rock roadways and active-passive full-space collaborative control technology.

Controlling the stability of deep high-stress fractured soft rock roadways is a key scientific issue in mining engineering. Using the south wing return-air roadway at the - 650 level of Yangcheng Coal Mine as the engineering background, this study performed mechanical property tests, mineral composition analysis, and in-situ stress tests on the surrounding rock. It further investigated the failure mechanisms and control strategies from the perspectives of lithology and stress environment. The results indicate that the main causes of large deformation in the roadway are: high in-situ stress, high clay mineral content (> 50%) in the soft surrounding rock, superimposed mining-induced stress, and the lack of coupling between the support structure and the surrounding rock. We proposed an active-passive full-space collaborative control technology consisting of concrete-filled steel tubular supports, bolt-mesh-shotcrete, and surrounding rock grouting. Using similar simulation, we investigated the stress distribution of the surrounding rock, deformation characteristics of support structures, load-strain response of supports, and displacement evolution of the surrounding rock under coupled static-dynamic loading. The results demonstrate the excellent bearing performance of concrete-filled steel tubular supports under high static loads and strong disturbances. Field monitoring results show that the maximum roof subsidence was 51 mm, floor heave 106 mm, and side convergence 77 mm. These data indicate that the deformation and failure of the surrounding rock have been effectively controlled. This study provides a theoretical basis and technical support for surrounding rock control in deep, high-stress, fractured soft rock roadways.

Mechanism and control of toppling instability in anti-dip rock slopes reinforced by negative Poisson’s ratio anchor cables under mining-induced unloading

Creep characteristics and nonlinear creep modeling of water-bearing sandy mudstone under triaxial loading conditions

Study on stability assessment of buckling failure and rainfall-induced instability mechanism for steeply inclined rock slope

To address challenges associated with the stability assessment and engineering control of buckling failure in steeply inclined rock slopes, this study takes the southern slope of the Longyu Open-Pit Mine as a case study and adopts an integrated approach combining theoretical modeling, field monitoring, and numerical simulation. First, under the assumptions of coordinated deformation and small strain, a differential equation governing the behavior of the surface rock layer is derived. This leads to the formulation of a safety factor defined as the ratio of the critical to the actual slope length. The analysis indicates that the slope remains stable when the thickness of the rock layer exceeds 10 m and the elastic modulus is greater than 32 GPa, thereby establishing a robust mechanical model for buckling failure. Second, based on field monitoring data of displacement and strain, orthogonal testing and factor sensitivity analyses are conducted. The results reveal the following ranking of influential factors: rock layer thickness ( R = 0.38+39.8 %) is an exceptionally sensitive positive factor; cohesion ( R = 0.25) is a highly sensitive positive factor; unit weight and groundwater level are significantly sensitive negative factors; whereas the influence of elastic modulus is negligible ( R = 0.03). These insights provide a clear priority hierarchy for monitoring and stability control measures. Finally, by incorporating real-time rainfall intensity data, FLAC3D simulations demonstrate a strong negative correlation between rainfall intensity and slope stability. Heavy rainfall is identified as a critical threshold triggering stability failure. Under such conditions, the maximum slope displacement increases by 175 %, reaching 5.5 m, and the shear strain increment develops into an arc-shaped sliding surface. The slope interval between 1360-1390 m is identified as the core risk zone, while the interval from 1290-1310 m acts as a key shear outlet. This clarifies the evolutionary pathway and key focus areas for preventing rainfall-induced instability. The findings of this study offer a solid theoretical foundation and practical technical support for the monitoring, risk warning, and engineering management of similar steeply inclined slopes.