Safety Analyses of Vehicle Travelling on High-speed Railway Bridge Excited by Pulse-like Near-fault and Non-pulse Ground Motions

AbstractTo explore the effect of canyon topography on the seismic response of railway irregular bridge–track system that crosses a V-shaped canyon, seismic ground motions of the horizontal site and V-shaped canyon site were simulated through theoretical analysis with 12 earthquake records selected from the Pacific Earthquake Engineering Research Center (PEER) Strong Ground Motion Database matching the site condition of the bridge. Nonlinear seismic response analyses of an existing 11-span irregular simply supported railway bridge–track system were performed under the simulated spatially varying ground motions. The effects of the V-shaped canyon topography on the peak ground acceleration at bridge foundations and seismic responses of the bridge–track system were analyzed. Comparisons between the results of horizontal and V-shaped canyon sites show that the top relative displacement between adjacent piers at the junction of the incident side and the back side of the V-shaped site is almost two times that of the horizontal site, which also determines the seismic response of the fastener. The maximum displacement of the fastener occurs in the V-shaped canyon site and is 1.4 times larger than that in the horizontal site. Neglecting the effect of V-shaped canyon leads to the inappropriate assessment of the maximum seismic response of the irregular high-speed railway bridge–track system. Moreover, engineers should focus on the girder end to the left or right of the two fasteners within the distance of track seismic damage.

Download Full-text

The Seismic Response of High-Speed Railway Bridges Subjected to Near-Fault Forward Directivity Ground Motions Using a Vehicle-Track-Bridge Element

Shock and Vibration ◽

10.1155/2014/985602 ◽

2014 ◽

Vol 2014 ◽

pp. 1-17 ◽

Cited By ~ 3

Author(s):

Chen Ling-kun ◽

Jiang Li-zhong ◽

Guo Wei ◽

Liu Wen-shuo ◽

Zeng Zhi-ping ◽

...

Keyword(s):

High Speed ◽

Ground Motions ◽

Element Model ◽

Railway Vehicle ◽

Vertical Acceleration ◽

High Speed Railway ◽

Near Fault ◽

Pulse Effect ◽

Short Period ◽

Track Bridge

Based on the Next Generation Attenuation (NGA) project ground motion library, the finite element model of the high-speed railway vehicle-bridge system is established. The model was specifically developed for such system that is subjected to near-fault ground motions. In addition, it accounted for the influence of the rail irregularities. The vehicle-track-bridge (VTB) element is presented to simulate the interaction between train and bridge, in which a train can be modeled as a series of sprung masses concentrated at the axle positions. For the short period railway bridge, the results from the case study demonstrate that directivity pulse effect tends to increase the seismic responses of the bridge compared with far-fault ground motions or nonpulse-like motions and the directivity pulse effect and high values of the vertical acceleration component can notably influence the hysteretic behaviour of piers.

Download Full-text

Nonlinear seismic assessment of isolated high-speed railway bridge subjected to near-fault earthquake scenarios

Structure and Infrastructure Engineering ◽

10.1080/15732479.2019.1639775 ◽

2019 ◽

Vol 15 (11) ◽

pp. 1529-1547 ◽

Cited By ~ 1

Author(s):

Ling-kun Chen ◽

Li-zhong Jiang ◽

Hong-xi Qin ◽

Nan Zhang ◽

Liang Ling ◽

...

Keyword(s):

High Speed ◽

Seismic Assessment ◽

Railway Bridge ◽

High Speed Railway ◽

Earthquake Scenarios ◽

Near Fault

Download Full-text

Seismic damage features of high-speed railway simply supported bridge–track system under near-fault earthquake

Advances in Structural Engineering ◽

10.1177/1369433219896166 ◽

2020 ◽

Vol 23 (8) ◽

pp. 1573-1586 ◽

Cited By ~ 5

Author(s):

Wei Guo ◽

Xia Gao ◽

Ping Hu ◽

Yao Hu ◽

Zhipeng Zhai ◽

...

Keyword(s):

High Frequency ◽

High Speed ◽

Seismic Damage ◽

Railway Bridge ◽

High Speed Railway ◽

Railway Bridges ◽

Simply Supported ◽

Near Fault ◽

Track System ◽

Pulse Type

Seismic loads pose a potential threat to the high-speed railway bridges in China, which have been rapidly developing in recent years, especially for those subjected to the near-fault earthquakes. The previous researches on high-speed railway bridges usually concern the far-field earthquake, and the damage of high-speed railway bridge–track system subjected to the near-fault earthquake has not been well studied. In this article, a seven-span high-speed railway simply supported bridge–track system is selected to explore the seismic damage features under the excitation of near-fault earthquake which possesses characteristics of obvious velocity pulse and high-frequency vibration. First, a detailed finite element model of the selected bridge–track system is established and calibrated by the experimental data and design code. Then the low-frequency pulse-type portion and the high-frequency background portion are separated from the selected eight original near-fault records, and a series of nonlinear dynamic analysis is conducted. The results show that the background portion leads to more serious damage of the bridge–track system than the pulse-type portion. Due to the high stiffness of high-speed railway bridge–track system, the background portion with high-frequency vibration characteristic produces the main part of seismic response of system. As for the damage part of system, the weakest component of the bridge–track system is the sliding layer, followed by the shear alveolar.

Download Full-text