The global force relationship is given by the equation F = K D {\displaystyle F=KD} , where F {\displaystyle F} is the resultant force matrix, K {\displaystyle K} is the global stiffness matrix, and D {\displaystyle D} is the global displacement matrix.
In matrix format,
k e = k e [ ( l e ) 2 ( l e m e ) − ( l e ) 2 − ( l e m e ) ( l e m e ) ( m e ) 2 − ( l e m e ) − ( m e ) 2 − ( l e ) 2 − ( l e m e ) ( l e ) 2 ( l e m e ) − ( l e m e ) − ( m e ) 2 ( l e m e ) ( m e ) 2 ] {\displaystyle k^{e}=k^{e}{\begin{bmatrix}(l^{e})^{2}&(l^{e}m^{e})&-(l^{e})^{2}&-(l^{e}m^{e})\\(l^{e}m^{e})&(m^{e})^{2}&-(l^{e}m^{e})&-(m^{e})^{2}\\-(l^{e})^{2}&-(l^{e}m^{e})&(l^{e})^{2}&(l^{e}m^{e})\\-(l^{e}m^{e})&-(m^{e})^{2}&(l^{e}m^{e})&(m^{e})^{2}\end{bmatrix}}}
