目的 为提高工程防护结构的动态弯曲性能，提出一种利用泡沫混凝土作为芯层材料的填充薄壁方管结构形式。方法 对填充不同密度的泡沫混凝土薄壁方管进行准静态和动态低速冲击三点弯曲实验，研究填充结构的弯曲行为。通过数值模拟分析管壁厚度、芯层长度以及冲击速度对填充结构弯曲性能的影响，探讨芯层与管壁二者间的相互作用以及协同变形机理。结果 相比空管结构，准静态和动态弯曲下泡沫混凝土填充管的平均压溃载荷可分别提高88.26%和80.04%。结论 准静态下填充管结构的弯曲性能由局部失稳凹陷和全局弯曲共同决定，而动态下的弯曲性能则由局部坍塌变形主导。

In order to improve the dynamic bending properties of engineering protective structures, the work aims to propose a thin-walled square tube structure with foam concrete as the core layer. The quasi-static and dynamic low-speed impact three-point bending experiments were carried out to study the bending behavior of the thin-walled square tubes filled with different densities of foam concrete. The effects of tube wall thickness, core layer length and impact velocity on the bending properties of the filled structure were analyzed by numerical simulation, and the interaction and co-deformation mechanism between the core layer and the tube wall were discussed. Compared with empty tube structure, the average crushing load of foam concrete-filled tube under quasi-static bending and dynamic bending increased by 88.26% and 80.04%, respectively. The bending properties of filled tube structures under quasi-static conditions are determined by local buckling and global bending, while the bending properties under dynamic conditions are dominated by local collapsing deformation.