One-Step FE Model Updating Using Local Correspondence and Mode Shape Orthogonality

Figure 1

Plot of the structure of the matrix from equation (15). Only a limited number of FE mode shapes around the frequency of the test mode shape are used in LC. This means that the matrix will have nonzero entries in a narrow band only, illustrated by black circles. If the mode actually contributes to the expansion in this experiment, the circle is filled. Thus in this experiment, we use a 5-dimensional subspace for expansion and use anywhere from one to all five modes in the expansion, corresponding to columns of .