为安全经济地设计铝合金腔体复合构件，使其达到加固要求，以铝合金腔体复合构件在加固过程中的实际工况为背景，对其抗弯性能进行试验研究，并采用数值模型进行验证。通过描述试件的加载破坏过程，分析各类试件的破坏机制，得到试件的承载力、延性和抗弯刚度的增长规律。试验结果表明： 1）砂浆压碎或铝合金拉断是铝合金腔体复合构件丧失承载能力的标志； 2）砂浆材料能显著提升试件承载能力，并降低试件延性，对试件抗弯刚度贡献不大； 3）碳纤维材料能显著提升试件抗弯刚度，并有限地提升试件的延性和承载能力。

In order to design an economic and safe aluminum alloy cavity composite member to reach reinforcement requirement, the bending performance of aluminum alloy cavity composite member is studied considering the actual working conditions of aluminum alloy cavity composite members in the reinforcement process, and it is verified by numerical model. Firstly, the loading and failing process of specimens are described. And then the failure mechanism of specimens in various types is analyzed and the growth trend of bearing capacity, ductility and bending stiffness of specimens are obtained. The results show that: (1) The mortar crushing or aluminum alloy breaking is the sign that the aluminum alloy cavity composite member loses its bearing capacity. (2) The mortar material can significantly improve the bearing capacity of the specimens and reduce the ductility, but contributes little to the bending stiffness of the specimens. (3) The carbon fiber material can significantly improve the bending stiffness of the specimens and increase the ductility and bearing capacity of limitedly.