QUESTION 5. (13 marks) a. Draw the axial load -moment- interaction curve for the column cross section shown in Figure 3(a). Include the squash load, transition point, balance point and flexural failure point. (9 marks) b. The 600 mm x 400 mm column cross section in Figure 3(a) is used to construct the 2.1 m column with pinned ends shown in Figure 3(b) and which is subjected to a 2000 kN axial load that remains unchanged over the column height. Using the column interaction diagrams in Figure 4 as well as the column interaction diagram drawn in in Q5 (a), determine the quantity of reinforcement required if the column is subjected to an axial load of 2000kN at an eccentricity about the x-axis of ex = 450 mm and ey = Omm as in Figure 3(c). (4 marks) For all calculations ignore capacity reduction factors. (b) (c) 2000 KN (a) e = 450 mmk e = 450 mm 75 mm 75 mm y T f. = 32 MPa f = 500 MPa = 200 GPa O 600mm 525mm 210 mm 600mm 525mm 400mm 32 mm diameter 400mm ex = 450 mm Figure 3 column cross sections elevations 16000 0, 14928 14000 0, 12828 12000 0, 10728 10000 reinforcement ratio: 1% 2% 3% 0,8628 N (KN) 8000 1155, 8517 946, 7587 737,6657 528, 5727 6000 4% 4000 897, 2496 2000 1343, 2376 1788, 2256 2136, 2234 0 501,0 500 1431, 0 967,0 1000 M (kNm) 1937,0 2000 0 1500 2500 Figure 4: column interaction diagram bending about the x-axis QUESTION 5. (13 marks) a. Draw the axial load -moment- interaction curve for the column cross section shown in Figure 3(a). Include the squash load, transition point, balance point and flexural failure point. (9 marks) b. The 600 mm x 400 mm column cross section in Figure 3(a) is used to construct the 2.1 m column with pinned ends shown in Figure 3(b) and which is subjected to a 2000 kN axial load that remains unchanged over the column height. Using the column interaction diagrams in Figure 4 as well as the column interaction diagram drawn in in Q5 (a), determine the quantity of reinforcement required if the column is subjected to an axial load of 2000kN at an eccentricity about the x-axis of ex = 450 mm and ey = Omm as in Figure 3(c). (4 marks) For all calculations ignore capacity reduction factors. (b) (c) 2000 KN (a) e = 450 mmk e = 450 mm 75 mm 75 mm y T f. = 32 MPa f = 500 MPa = 200 GPa O 600mm 525mm 210 mm 600mm 525mm 400mm 32 mm diameter 400mm ex = 450 mm Figure 3 column cross sections elevations 16000 0, 14928 14000 0, 12828 12000 0, 10728 10000 reinforcement ratio: 1% 2% 3% 0,8628 N (KN) 8000 1155, 8517 946, 7587 737,6657 528, 5727 6000 4% 4000 897, 2496 2000 1343, 2376 1788, 2256 2136, 2234 0 501,0 500 1431, 0 967,0 1000 M (kNm) 1937,0 2000 0 1500 2500 Figure 4: column interaction diagram bending about the x-axis