结构用冷弯空心型钢（GB/T6728—1986）(1)尺寸规格见表1一表3表1方形空心钢的尺寸规格A一边长t一壁厚R一外圆弧半径边长／mm尺寸允许偏差／mm壁厚t／mm理论质量／(kg／m)截面面积/cm2边长/mm尺寸允许偏差壁厚t/mm理论质量／(kg／m)截面面积／cm2A普通精度较高精度A普通精度较高精度25±O.60±0.301.20.8671.10580±1.40±O.703.07.0719.0081.51.06l1.3524.09.22211.7471.751.2151.5485.O11.20914.3562.01.3631.73690±1.50±0.75...
