泡沫混凝土填充圆钢管的轴压力学性能

采用试验和有限元模拟方法，研究泡沫混凝土填充圆钢管构件在轴压荷载作用下的力学性能. 通过轴压试验，分析短柱构件的耗能能力和长柱构件的轴压承载力，短柱构件发生叠缩破坏变形模式，耗能能力随着泡沫混凝土密度的提高而显著增强，长柱构件发生整体失稳破坏，稳定承载力随着泡沫混凝土密度的增大而增大. 基于ABAQUS的Explicit求解器，建立泡沫混凝土填充圆钢管构件的数值模型，获得的模拟结果与试验结果吻合良好. 开展参数分析，讨论径厚比、长细比及填充泡沫混凝土密度等因素对长柱构件承载能力的影响. 研究结果表明：长柱构件的稳定承载力随着长细比和径厚比的增大而减小，随着填充的泡沫混凝土密度的增大而增大. 基于Perry-Robertson公式，推导了泡沫混凝土填充圆钢管长柱构件的稳定承载力公式. 预测结果表明，该公式能够很好地预测长柱构件的稳定承载力.

Mechanical properties of circular steel tube filled withfoam concrete under axial loads

The mechanical property of circular steel tube filled with foam concrete under axially compressive loads was analyzed with both experimental and numerical methods. The energy dissipation capacity of short column members and the axial load bearing capacity of long column members were analyzed by axial compressive experiments. Results showed that short column members failed with progressive folding and energy dissipation increased with the increase of foam concrete density. In the case of long column members, the overall instability failure occured, and the stable bearing capacity increased with the increase of foam concrete density. A numerical model based on ABAQUS Explicit solver was proposed, and the simulation results agreed well with the experimental results. The effects of foam concrete density, diameter-to-thickness ratio and slenderness ratio to specimen’s bearing capacity were analyzed. Results showed that the bearing capacity of long column members decreased with the increase of the diameter-to-thickness ratio and slenderness ratio, while increased with the increase of density of the filled foam concrete. A formula of stability capacity of long column members was derived based on the Perry-Robertson formula. The calculation results of the formula show that this formula can predict the axial load bearing capacity of long column members well.