长期荷载作用下钢-竹组合柱的力学性能

Mechanical Properties of Steel-Bamboo Composite Columns under Long-Term Loading

为研究钢-竹组合工字形柱(以下简称组合柱)在长期荷载作用下的力学性能,设计制作了18个组合柱试件,依次对其实施一次加载试验、长期加载试验与二次加载试验,观测并分析试件的蠕变过程,研究组合柱承载力与形变的影响因素及其变化规律.结果表明:组合柱有良好的整体性与承载能力,加载至60 d时蠕变变形已达蠕变总量的90%,Burger模型可以准确地描述组合柱的蠕变过程;长期荷载作用后,组合柱的延性与极限应变明显提高,极限承载力受长期荷载作用影响较小,承载力与延性随着含钢率的增加显著提升.

To investigate the mechanical properties of steel-bamboo Ⅰ-section composite column under long-term loading, 18 specimens were designed and manufactured. Static loading test, long-term loading test and secondary static loading test were carried out successively, in which the creep process were measured and analyzed, influencing factors of bearing capacity and deformation and their variation rule were studied. Results show that the steel-bamboo Ⅰ-section composite column has high integrity and bearing capacity, the creep deformation reached 90% of the total creep when loaded for 60 days, the Burger model can accurately describe the creep process of the composite column. The ductility and ultimate strain are significantly increased after long-term loading, while the ultimate bearing capacity is not greatly affected, the bearing capacity and ductility are improved with the increasement of steel ratio.