There are two different constitution forms for the square tubes with ribs in the test specimens, one consists of two welded channels with stiffening lips (channel tubes), stiffening lips (angle tubes).

• 根据无肋、单向设置斜肋和双向设置斜肋3种截面形式、2种截面尺寸的18个薄壁钢管混凝土轴压短柱试验结果，比较和分析了各试件的试验现象、破坏模式及荷载－位移曲线等。