Experimental estimation of time variant system reliability of vibrating structures based on subset simulation with Markov chain splitting

•New test method to estimate time variant reliability of vibrating systems.•Sampling variance reduction via subset simulation and MCMC sampling.•Illustrative studies on a nonlinear building frame under bi-axial earthquake load. The study investigates the application of ideas from variance reduction schemes, developed in the area of computational structural reliability modelling, to the problems of experimental estimation of time variant reliability of randomly excited vibrating structures. The study considers series/parallel system reliability of vibrating systems under multi-component random excitations. An experimental protocol, based on subset simulation with Markov chain splitting, is proposed to estimate probabilities of failure as low as 10−5 to 10−4 with a relatively smaller number of samples and hence with reduced test times. Illustrative examples consist of earthquake shake table studies on a three-storied bending-torsion coupled building frame under bi-axial nonstationary, random earthquake support motions.