中文摘要：

为研究摇摆柱海洋平台结构的摇摆柱构造形式,研究制作了10个组合型钢管混凝土构件,采用圆钢管、圆钢管-工字钢、圆钢管-圆筒、方钢管、方钢管-工字钢、方钢管-圆筒6种截面形式进行三点弯曲试验.研究了不同形状、截面形式的组合型钢管混凝土在三点弯曲试验过程中的破坏过程,包括破坏形态、承载能力和变形能力;并且通过局部横纵比和局部应变分析加载后试件内部变化和受力特征.试验结果表明：试件在加载过程中,钢管与混凝土以及钢管混凝土中内置的型钢在不同阶段有着不同的受力特征和协同工作机理;圆钢管混凝土更有利于钢管对混凝土发挥套箍作用,从而提高构件承载能力和变形能力;内置圆筒的双圆筒截面形式构件抗剪性能最好.

英文摘要：

To study the internal structure of rocking column used in offshore platform, 10 Concrete Filled Steel Tubular （ CFST） column specimens subjected to three-point bending test were tested, including concrete filled round steel tube, concrete filled round steel tube with inner I-cross section, concrete filled round steel tube with inner circular cross section, concrete filled square steel pipe, concrete filled square steel tube with inner I-cross section, concrete filled square steel tubes with inner cylindrical cross section. Failure process, failure modes, the bearing capacity and deformation capacity of CFST columns were studied considering different shapes and different section forms, and the internal changes and mechanical characteristics of specimens were analyzed which were loaded by local transverse-longitudinal ratio and the local strain. The test results show that when specimens are in the process of loading, steel tubular and concrete as well as internal different cross-section steel have different mechanical characteristics and collaborative work mechanisms at different loading stages. Circular CFSTs have better＆amp;nbsp;ferrule effects which can enhance the bearing capacity and deformation capacity of specimens;the CFSTs with two cylindrical cross sections have the best shear performances.