The buckling and sudden capacity loss of the compression member can be prevented using a proposed tube in tube force limiting device (TTFLD). In this way, the brittle post-buckling behavior of the compression member can be converted into an elasto-plastic behavior. The TTFLD consists of two tubes with unequal diameter, one of which is placed into the other tube. The outer tube operates as a casing for the inner compression tube and the flexural stiffness of the outer tube restrains the buckling of the inner tube. The present study has experimentally investigated and evaluated a number of experimental specimens. Next, numerical analysis of these specimens has been done using finite element software. Further, the behavior of the tube in tube force limiting device have been investigated under important parameters such as the gap between the inner and outer tubes (gap), the inner tube or main member slenderness ratio (λ), and the ratio of outer tube length to inner tube length \(\left( {L_{2} /L_{1} } \right)\), by extending the numerical studies to further examples. Using this TTFLD is an effective, simple and economical method to prevent the buckling of compression member and can lead to a favorable increase in the bearing and deformability capacity of the compression members with different values of slenderness ratio. The compressive strength of the member will increase significantly, if the gap size is less than about 43% of the inner tube’s gyration radius, and the length ratio is greater than about 55%.

中文翻译：

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管限力装置中管的实验与数值研究

使用提出的管中管力限制装置（TTFLD）可以防止压缩构件的屈曲和突然的容量损失。以这种方式，压缩构件的脆性后屈曲行为可以转化为弹塑性行为。TTFLD由两根直径不相等的管组成，其中一根放置在另一根管中。外管用作内压缩管的外壳，并且外管的抗弯刚度限制了内管的屈曲。本研究通过实验研究和评估了许多实验标本。接下来，使用有限元软件对这些样本进行了数值分析。进一步，\（\ left（{L_ {2} / L_ {1}} \ right）\），通过将数值研究扩展到其他示例。使用这种TTFLD是防止压缩构件弯曲的有效，简单且经济的方法，并且可以导致具有不同的细长比的压缩构件的轴承和变形能力的有利增加。如果间隙尺寸小于内管回转半径的约43％，且长度比大于约55％，则构件的抗压强度将显着提高。