Distribution Factors:
As the supports A and D are fixed, the distribution factor in the members AB and DC are both zero, (DF)AB = (DF)DC = 0.
At joint B, the relative stiffnesses of the members are
KBA =I/6 and KBC =2I/6 =I/3
∴ (DF )BA = (I/6)/(I/6)+(I/3) = 1/3 and (DF)BC =2/3
At joint C, the relative stiffnesses of members are
KCB = 2I/6 =I/3 and KCD = I/3
(DF)CB = (I/3)/(I/3)+(I/3) =1/2 and (DF)CD =1/2
The moment distribution with the above assumed moments are given in the table below :
![2295_Distribution Factors1.png](https://www.expertsmind.com/CMSImages/2295_Distribution%20Factors1.png)
where K is an unknown multiplying factor.