Distribution Factors:
Joints A and D are fixed therefore, there will not be any distribution of moments there and (DF) AB = 0 and (DF) DC = 0.
At joint B, there are two members BA and BC meeting. Their relative stiffnesses are K BA = I/3, and K BC = 2I/6 = I/3
∴ (DF )BA =(I/3)/(I/3)+(I/3) =0.5 and (DF)BC = 0.5
Similarly, at joint C we have (DF)CB = 0.5 and (DF)CD = 0.5.
A moment distribution is made joint-wise and member-wise as shown below:
