Long-term dynamic characteristics and cumulative strain prediction modeling of round gravel foundation under cyclic subway loading

Description

Haijun Huang and colleagues shake rounded gravel under repeated subway-like loading in a large laboratory press, in a 2026 geotechnical study. Metro tunnels increasingly pass through round gravel layers in Chinese cities, and years of train vibration can settle the ground unevenly. Using saturated samples in a dynamic triaxial machine, the team varied packing density, confining pressure, and shaking strength to watch stiffness and permanent strain evolve.

Looser, shallow gravel under strong shaking accumulated deformation that could endanger shallow tunnels, while deeper burial looked safer. Packing the gravel denser and raising confining pressure stiffened it, cut permanent and elastic strain, lowered water pressure buildup, and strengthened resistance to liquefaction. Drawing on time-hardening theory, the authors fitted a prediction model joining all three factors, aimed at design checks and long-term settlement forecasts for subway foundations.

Catalog record

Source: https://europepmc.org/article/MED/PMC13549959