From a reinforcement point of view, the G1-2 consists of three boundary (hidden) columns: the 450/450/250/250 ‘L’ section column a1-2, the rectangular column a1-0 with a cross section of 250/450, the 450/250 rectangular column a2-0 and the shear walls’ main bodies Sh1 and Sh2 with sections equal to 250/1200 and 1500/250 respectively.