本文主要利用ABAQUS軟體分析探討雙鋼管混凝土柱(DS-CFT)受到純彎矩、純軸壓以及固定軸壓下施加純彎矩的行為，並將分析結果與國家地震中心實驗數據比較，藉此可以瞭解混凝土在這些載重作用下的DS-CFT中可能產生之圍壓(Fl)效果、混凝土軟化參數(K3)以及混凝土強度折減係數(K4)，如此將可得知混凝土在DS-CFT中所能產生之效益，以及推算材料參數用的經驗公式。

由分析的結果可知，在純彎矩作用下，雖然因缺乏軸壓而無法讓混凝土之耐壓特性充分發揮，因而強度相較於其他試體相對的低，但是DS-CFT仍然能提供一定程度的圍壓，整體而言DS-CFT所能提供的圍壓比CFT要來的大上許多。

同時也發現，CFT的經驗公式以及K2不適用於DS-CFT的試體，CFT試體使用的K2值會造成試體應變過大而偏軟，因此本文做了反覆的多次嘗試，歸納出新的K2後，重新進行分析而找出了每根試體所適用的材料參數與經驗公式。

This paper use ABAQUS software to analyse the Double-Skin Concrete Filled Tubes (DS-CFT) that subject to axial compression and bending moment, then compare the analysis results with experimental data of national earthquake center. By the way, we can find the Fl, K3, and K4 of a DS-DFT subject to such loads, understand the benefit that concrete can produce in DS-CFT so, and calculate the experience formulas used for material parameters.

By the result analysing, we can find that the specimen under pure bending can’t let the concrete keep its compressive resistibility because of lacking the axial compression, therefore the strength of such specimen is less than others, but DS-CFT can still offer a certain Fl that is much stronger than CFT.

Besides, we find the experience formula and K2 of CFT are not suitable for DS-CFT specimens, K2 value of CFT will lead to a strain that is too large. so this paper repeated trying for many times, induct new values of K2, and find out the suitable material parameters and experience formulas again.

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