短语词组短语box corner column 箱形角柱box steel column 箱形钢柱box type column [建]方立柱concrete box pier column 混凝土箱形墩柱box -column to I-beam connection 箱型柱box x column 箱形柱welded box cross column 箱型组合截面box shape steel column 箱形钢柱 返回 box column