Fillers can improve the tensile performance of ductile tubes. Mechanical analyses of tensile tubes with filler have generally focused on experimental and numerical studies on concrete-filled steel tube (CFST) components, while mechanical performance of tensile tubes with flexible supporting fillers has rarely been investigated. In the current research, we have proposed a “steel tube+pre-stressed flexible internal support” structure. Meanwhile, strengthening of tensile thin-walled tubes with internal supports was studied in terms of stress and deformation. The trends of yield strength and ultimate strength of tensile tubes were determined and calculation equations of yield strength and normal ultimate strength of tensile tubes with internal support were derived. Strengthening coefficient variations as functions of radius-thickness ratios of steel tubes and elastic moduli of internal supports as well the optimized internal support p corresponding to maximum increment of tensile performance of tubes were also determined. It was experimentally verified that the initial supporting pre-stress of internal support on steel tubes could be achieved by cold shrink fitting technique. Experimental results revealed that the developed composite structure significantly enhanced the mechanical performance, fracture toughness, and energy consumption characteristics of tensile tubes. Hence, the proposed structure was confirmed to have promising applications.

填料可以提高韧性管的拉伸性能。带有填料的拉伸管的力学分析通常集中在钢管混凝土 (CFST) 组件的实验和数值研究上，而很少研究带有柔性支撑填料的拉伸管的力学性能。在目前的研究中，我们提出了“钢管+预应力柔性内支撑”的结构。同时，从应力和变形方面研究了带内支撑的拉伸薄壁管的强化。确定了抗拉管屈服强度和极限强度的变化趋势，推导出了内支撑抗拉管屈服强度和法向极限强度的计算方程。还确定了对应于管材拉伸性能最大增量的p。经实验验证，钢管内支撑的初始支撑预应力可以通过冷缩配合技术实现。实验结果表明，所开发的复合结构显着提高了拉伸管的力学性能、断裂韧性和能耗特性。因此，所提出的结构被证实具有有希望的应用。