Effect of filling material on dynamic response and energy dissipation in sandstone with double weak interlayers

作者：Yanzhe Li, Chuanxin Rong, Zhensen Wang, Yang Wang · 发表于：Results in Engineering · 年份：2025 · DOI：10.1016/j.rineng.2025.106965 · 被引用次数：2 · 研究领域：Geophysical Methods and Applications、Rock Mechanics and Modeling、Grouting, Rheology, and Soil Mechanics

With the extension of China's transportation infrastructure into the complex geological areas in the west, the presence of numerous weak interlayers in the geology has posed significant challenges to the construction of tunnel transportation. This study investigates the dynamic response and energy dissipation mechanisms of sandstone specimens with double weak interlayers under impact loading using split Hopkinson pressure bar (SHPB) tests. Three filling materials—gypsum, cement-gypsum mortar, and epoxy resin—were tested at varying impact velocities (4.77–6.66 m/s). Results indicate that the dynamic compressive strength and energy dissipation capacity depend significantly on the filler’s strength and plasticity. Epoxy resin, with superior strength and ductility, exhibited the highest peak stress (38 MPa) and energy dissipation, followed by cement-gypsum mortar (29 MPa) and gypsum (23 MPa). Crack propagation analysis revealed distinct failure modes: shear failure in gypsum-filled specimens and compressive-shear failure in epoxy and mortar samples. Energy evolution analysis demonstrated that absorbed and dissipated energies increased quadratically with impact velocity. Damage variables, derived from energy dissipation, linearly correlated with velocity. These findings provide critical insights into optimizing engineering designs for rock masses with weak interlayers under dynamic loads.