On substituting equation(10.84) into the first set of equation (10.83), we get
which can be can be written as
where is the condensed stiffness matrix. Now internal DOFs could be eliminated from the shape assumed functions also. On substituting a , b , and c obtained from equation (10.67)into equation , we get
which could be simplified as
with
Similarly, on substituting a , b and c obtained from equation(10.84) in equation (10.86), we get
with
10.3.3 Weak Formulation of the Timoshenko Beam Element for the Dynamic Case
For dynamic case the shape functions derived in the previous section will still be valid and could take the following form