Investigation on the Influence of Structural Surface Characteristics on Stress Wave Propagation Behavior

Pengxu Jing ^1,2 Haiying Wang ² Yang Wang ² Wenbo Zheng ^1* Haitao Yang ³

• ¹ Chang’an University, Xi'an, China
• ² Key Laboratory of Life Search and Rescue Technology for Earthquake and Geological Disaster, Ministry of Emergency Management, Beijing, China
• ³ College of Earth Science and Engineering, Shandong University of Science and Technology, Qingdao, Shandong Province, China

The propagation of stress waves in rock slopes is influenced by various factors, including the characteristics of structural planes (stiffness, number, spacing, thickness), sawtooth-shaped structural features (stiffness, angle), filling materials (fully or partially filled), and wave impedance, causing phenomena such as stress wave attenuation, signal delay, and reduced wave speed. Investigating the influence of structural planes on the propagation characteristics of stress waves is crucial. To thoroughly examine the impact of structural planes on stress wave propagation, this study employs a one-dimensional Hopkinson bar model to systematically analyze wave behavior under varying structural plane conditions. Key parameters such as permanent displacement, acceleration, and stress were monitored, leading to several important findings: when the structural plane stiffness exceeds a critical threshold (2.8×10⁶Pa), permanent displacement, acceleration, and stress values of the stress waves increase significantly with higher stiffness. Increased spacing between structural planes also leads to significant growth in these parameters, highlighting spacing as another key factor in stress wave propagation. Conversely, increasing the number and thickness of structural planes reduces the stress wave response parameters, reflecting the obstructive effect of denser and thicker planes on wave propagation. A larger angle in the sawtooth-shaped structural plane enhances stress wave reflection and attenuation, effectively reducing peak permanent displacement and acceleration values. This underscores the role of structural plane morphology in shaping stress wave propagation paths and energy distribution. The density of filling materials significantly affects stress wave propagation, with higher densities reducing energy dissipation and enhancing wave transmission. Significant wave impedance differences cause notable reductions in stress wave amplitude and propagation speed, emphasizing the importance of wave impedance matching. Higher damping ratios accelerate energy dissipation, significantly reducing the stress wave amplitude at the propagation endpoint. These findings offer a theoretical basis for understanding rock mass dynamics and assessing rock slope stability. The results provide valuable guidance for the engineering design and disaster prevention of geotechnical structures under complex geological conditions.