Energy absorption capacity of concrete-filled tube member (CFT) in CFT rock shed

• Impact resistance of CFT member in CFT rock shed was investigated. • Drop weight test with 1:5 scale specimens and FE analysis was performed. • Horseshoe-shaped CFT members showed good impact resistance performance. • Energy absorption capacity of CFT member can be evaluated by static nonlinear FE analysis. • Decreasing D/t ratio and increasing f y significantly enhanced energy absorption capacity. A rock shed is a rockfall protection facility installed in areas where large-scale rockfalls are expected, or where the installation of other rockfall protection facilities is not feasible. To increase the rockfall energy absorption capacity of rock sheds, the concrete-filled tube (CFT) rock shed was proposed. In this study, we evaluated the impact resistance and energy absorption capacity of the main CFT member in the CFT rock shed through experimental and numerical approaches. A series of drop-weight tests was conducted on small-scale CFT members in the proposed rock shed. Subsequently, the finite element analysis model was verified by comparison with the test results, and the energy absorption capacity of the main CFT member was evaluated. Furthermore, a parametric study was conducted to identify the effects of the diameter-to-thickness ratio, steel tube yield stress, and concrete infill compressive strength on the energy absorption capacity of the main CFT member.