The performance of reverse path methods applied to identify the underlying linear model of
base-isolated structures is investigated. The nonlinear rubber bearings are considered as nonlinear components
attached to an underlying linear model. The advantage of reverse path formulation is that it can separate the
linearity and nonlinearity of the structure, extract the nonlinearity and identify the underlying linear structure.
The difficulty lies in selecting the nonlinearity function of the hysteretic force due to its multi-valued property
and path-dependence. In the thesis, the hysteretic force is approximated by the polynomial series of displacement
and velocity. The reverse path formulation is solved by Nonlinear Identification through Feedback of Output
(NIFO) methods using least-square solution. Numerical simulation is carried out to investigate the identification