Axial compressive behavior of twining-bamboo-confined thin-walled steel tubular columns

摘要

To study the axial compressive behavior of twining-bamboo-confined thin-walled steel tubular (TBCST) columns, eight specimens were subjected to axial compressive tests. The effects of the diameter/thickness ratio of the steel tube, thickness and angle of the twining bamboo, and cross-sectional shape on axial compressive behavior were investigated using the verified finite-element (FE) model. Finally, the ultimate bearing capacities of circular and square composite columns were estimated through prediction equations. The results demonstrate that the failure modes of the TBCST columns are the steel tube partially denting inward and partially bulging outward at a certain distance from the end and the twining bamboo in the corresponding area rupturing. The ultimate load and ductility coefficient increase with an increase in the diameter/thickness ratio of the steel tube. A thickness of 10 mm and twining angle of 75 are the optimal parameters for the twining bamboo. Circular and square composite columns are respectively suitable for the conditions based on the bearing capacity and ductility as the main design basis. The results of the prediction equations are in good agreement with the test and FE results.