Seismic Reliability Analysis of Long-Span Single-Pylon Suspension Bridge Subject to Nonstationary Ground Motions

To efficiently and accurately evaluate the critical seismic response extreme value distribution (EVD) and seismic reliability analysis (SRA) of complex non-linear structures under nonstationary ground motions, a novel method for obtaining fractional moments via unequal weights combined improved correlation-reduced Latin hypercube sampling method (ICLHS) was proposed in this investigation. First, the basic theoretical methods of SRA were presented including dimension reduction simulation of nonstationary ground motions, single-loop maximum entropy theory of fractional moments, along with ICLHS for abtaining the fractional moments. Then, an effective structural seismic reliability assessment framework of complex nonlinear structures under nonstationary ground motions was built considering the double uncertainties of structural variables and seismic ground motions. and a three-story nonlinear shear frame structure was employed to verify the effectiveness of the proposed method. Finally, Based on the proprosed method and OpenSees finite element platform, the SRA of a typical long-span single-pylon suspension bridge was carried out and some critical conclusions were drawn.