29 Jun 2020
I am studying the connection point of the GEBT which is explained in the journal "GEBT A general-purpose ..." by W. Yu.
Is there any missing point in my understanding? Please help.
According to the paper, if one wants to add a revolute joint with a prescribed rotation at a connection point,
18N+12+3(moment at the connection) degrees of freedom will be the unknown vector.
For example, if the connection point is in between element i and j;
( element i ) - ( C ) - ( element j )
Then, the equilibrium equation for the adjacent element will be
(f_psi_i+) + (f_psi_j-) - M_C_hat = 0
-> (f_psi_i+) - M_C_hat = 0 because element j will freely rotate ?
corresponding compatibility equation is:
(f_M_i+) + theta_C_hat = 0, (f_M_j-) - theta_C_hat = 0,
-> (f_M_i+) + theta_C_hat = 0
where the second equation would vanish.