@inproceedings{scholars11701, journal = {IOP Conference Series: Earth and Environmental Science}, publisher = {Institute of Physics Publishing}, year = {2019}, title = {Nonlinear System Identification of Structures Subject to Stochastic Loadings}, number = {1}, note = {cited By 0; Conference of 2nd National Colloquium on Wind and Earthquake Engineering, NCWE 2018 ; Conference Date: 17 August 2018 Through 18 August 2018; Conference Code:146114}, volume = {244}, doi = {10.1088/1755-1315/244/1/012029}, author = {Lim, E. S. and Liew, M. S.}, issn = {17551307}, abstract = {This paper intends to explore the application of the Reverse Multiple Input Multiple Output (R-MISO) technique in the system identification of nonlinear structural behaviour. This paper introduces two concepts in improving the identification estimates of multiple inputs and nonlinear systems, which is the conditioned spectral estimation technique and the inversion of the frequency response function formulas. In this paper, a linear equation of motion with a nonlinear Duffing oscillator is modelled and tested using this technique in order to model the typical nonlinear stiffness characteristics of materials and their design limit. The results indicate a good fit between the predicted physical parameters and the model properties. The nonlinearities were successfully isolated in a non-iterative procedure and the parameters were correctly identified. Multiple coherency was used as a tool to describe the various contributions of the inputs to the system outputs. {\^A}{\copyright} 2019 Published under licence by IOP Publishing Ltd.}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85063517310&doi=10.1088\%2f1755-1315\%2f244\%2f1\%2f012029&partnerID=40&md5=91341d913e4e5ba088568d1518997286}, keywords = {Communication channels (information theory); Earthquake engineering; Engineering geology; Equations of motion; Frequency estimation; Frequency response; Geophysics; Iterative methods; MIMO systems; Nonlinear systems; Religious buildings; Spectrum analysis; Stochastic systems, Duffing oscillator; Equation of motion; Frequency response functions; Non-linear stiffness; Non-linear structural behaviours; Non-linear system identification; Physical parameters; Spectral estimation techniques, Nonlinear equations} }