研究方形薄壁型钢管/多层竹胶板组合空芯柱(Square, thin-walled steel tube/multi-layered bamboo plywood composite hollow column,SBCC)的轴心抗压性能,揭示其受力破坏机理,为其工程应用提供试验和理论基础。考虑试件的截面尺寸、空心率及长细比对SBCC抗压承载力的影响,设计制作了15根轴心抗压试件,通过SBCC的抗压性能测试,考察测试过程中的破坏形态和变形特征,分析各因素对试件轴心抗压力学性能的影响规律。试验结果表明:SBCC轴心抗压失效主要有竹胶合板材料破坏、基体胶结面开胶破坏以及整体失稳破坏3种形态,总体上胶结面间的胶粘强度及长细比是决定破坏模式的主要因素。SBCC的轴心抗压承载力随组合柱竹净截面面积、空心率的增大而显著提高,随长细比的增大而降低。通过试验数据的非线性回归分析,建立了SBCC的轴心抗压承载力计算公式,公式估算结果与试验测试结果的误差在20%以内。该研究结果表明SBCC是一种轴心抗压性能较优异的钢/竹组合结构单元,可实现“以竹代木”,作为工程结构用材的应用前景广阔。
The development of laminated-bamboo has broadened the application range of bamboo material in the field of structural engineering. A new type of steel/laminated bamboo composite column was developed based on the existing bamboo composite element for constructing multi-story, pre-fabricated, column-supported, and bamboo-framed buildings, and named as square thin-walled steel tube/multi-layered bamboo plywood composite hollow column (SBCC). The core of the SBCC is a square thin-walled steel tube, and the exterior column consists of several high-strength bamboo plywood pieces (such as bamboo mat plywood) that are bonded together using a structural adhesive to form a composite hollow column. SBCCs are a new type of steel/bamboo composite with excellent physical and mechanical properties. Multi-layered high-strength bamboo plywood forms the primary body in the SBCC that is subjected to compressive forces, and the square thin-walled steel tube only serves as a liner. Large numbers of bamboo are used, which reduce the manufacturing cost of the composite columns and result in a relatively high load-bearing capacity. A steel tube section is used in the column core to increase the cross-sectional size of the column, thereby reducing the slenderness ratio and effectively regulating the instability and failure of the columns under pressure. The composite has a simple cross-section, can be manufactured and processed simply, and is suitable for industrial production. This study aimed to study the axial compression performance of SBCCs, and explore its failure mechanism under axial loads in order to provide valuable information for its engineering applications. The influence of factors including bamboo-plywood net sectional dimension area, hollow ratio, and slenderness ratio on the mechanical performance and axial compression properties was investigated using 15 composite column specimens. The failure modes and deformation behavior of specimens were also analyzed in an axial compression test. Results showed that the com