Abstract:To mitigate disaster caused by the impact of debris flow boulders, a concrete filled steel tubular crib dam was proposed. Solid impact tests were carried out to study the impact dynamic response of the structure, and the response modes of the structure were summarized. The numerical simulation of the test process was performed, and the results were consistent with the test. The parameter analysis of the structure was carried out to study the influence of confinement coefficient of the piles, radius-thickness ratio of the braces, and stiffness ratio of piles and braces on the dynamic response of the structure. Results showed that the typical response modes of the structure included slight damage of member, bending failure of member, and joint failure. The structure performed good overall energy dissipation ability when the pile tube was impacted, while overall energy dissipation was not obvious when the brace tube was impacted. The influence of confinement coefficient of the piles, radius-thickness ratio of the braces, and stiffness ratio of piles and braces on the dynamic response of the structure was constrained by the single-factor variation of the diameter and thickness of piles and braces. These findings suggest that the concrete filled steel tubular crib dam provides good impact resistance.