The application of Karhunen–Loéve, or principal component analysis method, to study the non‐linear seismic response of structures

The Karhunen-Loeve (K-L) method is used to interpret dynamic response data obtained from shaking table and pseudodynamic tests conducted on civil engineering structures subjected to earthquake loading. It is shown how the K-L method can be used to monitor on-line, or a posteriori, the structural response of non-linear dynamical systems. Results from these analyses make it possible to quantitatively verify the number and participation factors of non-linear modes and how they correspond to physical behaviour of the structure, Comments are made regarding the use of this technique in various fields including numerical calculations, experiments and control.