Figure 2a shows a symmetrically reinforced concrete column with the total of 10-N16 bars. i. If the column at the balanced failure condition, calculate the axial load Nub and bending moment Mub in the major axis of bending. (You may use the M-N chart given in Figure 2b or calculate the first principles.) (12 Marks) ii. What is the maximum design axial force N", this column can carry when there is no external moment applied (considering only the minimum eccentricity as per AS3600)? (8 Marks) iii. If this column need to be designed for a combined design axial force N = 1000KN and design bending moment M* = 150kNm (about the major axis), what is the required steel area for this section (assume a similar reinforcement arrangement on 2 faces as shown in Figure 2a)? (10 Marks) 50 450 5-N16 5-N16 400 inlo SECTION Figure 2a Refer to question 2 20 - 10 f = 40 MPa 10 Fig 2a Important Notes In Figure 2b the p is given as As bD Where As is the Total steel area CHART 6.12 Rectangular 40 MPa g-0.9 2