Technical gazette, Vol. 23 No. 2, 2016.
Original scientific paper
https://doi.org/10.17559/TV-20151208071236
Analysis of a high-pier railway bridge under spatial stochastic stationary and non-stationary earthquake excitations
Jin Zhang
; School of Civil Engineering, Southwest Jiaotong University, No. 111, North 1st Section of Second Ring Road, Jinniu District, 610031, Chengdu City, Sichuan Province, China
Hongyu Jia
; (1) Department of Civil Engineering, Southwest Jiaotong University, Emei Campus, No. 1, Jingqu road, 614202 Emei, Sichuan Province, China; (2) College of Architecture & Civil Engineering, Beijing University of Technology, 100124, Beijing, China
Shixiong Zheng
; School of Civil Engineering, Southwest Jiaotong University, No. 111, North 1st Section of Second Ring Road, Jinniu District, 610031 Chengdu City, Sichuan Province, China
Shiqiang Qin
; School of Civil Engineering and Architecture, Wuhan University of Technology, No. 122, Luoshi road, 430070 Wuhan, Hubei Province, China
Keyue Zhang
; Department of Civil Engineering, Southwest Jiaotong University, Emei Campus, No. 1, Jingqu road, 614202 Emei, Sichuan Province, China
Abstract
The objectives of this paper are to perform a comparative analysis of the large-scale system of a high-pier railway bridge subjected to stationary and non-stationary spatially varying earthquake excitations using the pseudo-excitation method (PEM), and to estimate whether or not the non-stationary stochastic analysis of the high-pier railway bridges under tri-directional spatial ground motions can be simplified into a stationary random analysis to avoid excessive computation. Based on the finite element software ANSYS, the stationary and non-stationary stochastic excitations analyses of a high-pier bridge were transformed into harmonic analyses and deterministic transient analyses in the study, respectively, by using PEM. The wave-passage effect and the incoherence effect were modelled as the key factors, a total of twelve cases were considered to investigate the wave-passage effect and incoherence effect on the seismic response of a high-pier railway bridge under stationary and non-stationary earthquake excitations. Results show that structural responses under stationary excitation are larger than those under non-stationary by considering either the wave-passage effect or the incoherence effect. Through comparing structural responses under stationary excitation with those under non-stationary one, all the growth rates are less than 25 %, which is acceptable in engineering, meaning that a non-stationary stochastic analysis of high-pier railway bridges under tri-directional spatial ground motions can be simplified into a stationary analysis to avoid excessive computation.
Keywords
high-pier railway bridge; incoherence effect; non-stationary stochastic excitation; pseudo-excitation method; wave-passage effect
Hrčak ID:
156836
URI
Publication date:
27.4.2016.
Visits: 2.329 *