QUANTITIES FOR 914mm X COLUMN. SPIRAL WEIGHT = (211,473mm X kg/m) X 2 COLS. = 420 kg SPIRAL LENGTH = 84 X [(914mm 113mm) ]ÿ+ (75mm)ÿ= 211,473mmc. BAR NO. SIZE TYPE LENGTH WEIGHT * * THE SP1 SPIRAL REINFORCING STEEL SHALL BE W20 OR D20 COLD DRAWN WIRE OR #13 PLAIN OR DEFORMED BAR.