1. The problem statement, all variables and given/known data For the KAb and KCD , they are connected by the same method ... At B and C , we can see that they are connected by the same method , although i am not sure it's fixed or pinned . 2. Relevant equations 3. The attempt at a solution I assume they are fixed at B and C , so i agree that KAB is 4EI / L for far end fixed case . So , i think KCD should be 4EI / L as well .