林产工业

研究了竹-木组合空心圆柱加固圆木柱的承压承载能力，通过试验和理论分析，结果表明：组合柱经历弹性、弹塑性及塑性阶段，轴向荷载增大导致应变曲线斜率减小，组合柱失去承载能力前出现较大位移和压屈现象。套箍效应理论分析表明：当厚度t=1 mm时，出现“负套箍效应”，说明外包竹皮产生套箍效应需要一定的厚度。同时，竹-木组合空心圆柱受压组合弹性模量大于组合木材的受压弹性模量，小于外包竹皮的受压弹性模量，表明外包竹皮能够提高木柱的刚度，增强结构承载能力。在此基础上，提出考虑套箍效应的轴向承载力计算公式，并验证了其准确性和有效性。

The compressive bearing capacity of bamboo wood composite hollow circular columns was studied. Through experiments and theoretical analysis, the results showed that the composite columns went through elastic, elastoplastic, and plastic stages, and the increase in axial load led to a decrease in the slope of the strain curve, and the composite columns exhibited significant displacement and buckling before losing their bearing capacity. Theoretical analysis of the confining effect shows that a "negative confining effect" occurs when the thickness t=1 mm, indicating that a certain thickness is required for the bamboo skin to produce the confining effect. At the same time, the elastic modulus of the bamboo wood composite hollow circular columns under compression is greater than that of the composite timber and less than that of the outer bamboo skin, indicating that the outer bamboo skin can improve the stiffness of the wooden column and enhance the structural bearing capacity. On this basis, a calculation formula for axial bearing capacity considering the confining effect was proposed, and its accuracy and effectiveness were verified.