An I-Section with the sectional dimensions d = 325.8 mm, b f =309.8 mm , t f = 19.3 mm (b f and t f are the same for both flanges) and t w = 15.

An I-Section with the sectional dimensions d = 325.8 mm, bf=309.8 mm , tf = 19.3 mm (bf and tf are the same for both flanges) and tw = 15.0 mm, is subject to the permanent and imposed tensile actions of 621 kN and 1476 kN respectively. The I-Section is connected to 30 mm thick plates on both top and bottom flanges by M20 bolts. Assume the bolt setup is identical on both flanges and fy = 300 MPa and fu = 420 MPa. If a = 54 mm, b = 53 mm, design check the I-Section member (using the load case combination: 1.2x(permanent action) + 1.5x(imposed action)) and calculate the following for online submission:

1. The design axial tensile force (1 mark) (Unit: kN)
2. The gross cross sectional area of the I-Section (ignore the rounded corners) (1 mark) (Unit: mm2)
3. The net cross sectional area of the I-Section (4 marks) (Unit: mm2)
4. The section capacity of the I-Section member (4 marks) (Unit: kN)