The assembly of three steel bars shown in Fig. 12.4 supports a vertical load P. It can b...

The assembly of three steel bars shown in Fig. 12.4 supports a vertical load P. It can be verified that [see Ref. 12.5], the forces in the bars AD = CD and BD are, respectively,

Using these equations, calculate the value of ultimate load Pu. Given: Each member is made of mild steel with = 250 MPa and has the same cross-sectional area A = 400 mm², and α= 40º.