User:Eml4500.f08.ramrod.c/9-12-08

Lecture Notes for 9/12/08
In compact notation:


 * [kij] 6x6 {dj} 6x1 = {Fi} 6x1
 * (more generally, the matrices are nxn)

$$\sum_{j=1}^{6}{ K_{ij}d_j }\! = F_i$$,    i = 1, 2, 3, ...., 6

The three matrices used are shown below: 


 * K nxn = [Kij]nxn = global stiffness matrix


 * d nxn = {dj}nxn = global displacement matrix


 * F nxn = {Fi}nxn = global force matrix

Recall the element force-displacement relation
 * k (e)4x4 d (e)4x1= f (e)4x1


 * k n4x4 = [kij(e)] = element stiffness matrix


 * d nxn = {dj(e)} = element displacement matrix


 * F nxn = {fi(e)} = elementforce matrix