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Effects of shear panel dampers on seismic response mitigation of high-speed railway simply supported bridge-track system under far-field and near-field ground motions

Jiang Liqiang, Yu Kai, Jiang Lizhong, Wen Tianxing, Hu Yi, Pang Lin

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 2

art. no. e93, 2023

EN

High-speed railway lines always have to cross the seismic zone with great earthquake risks leading to serious consequences. A replaceable steel panel damper (SPD) is proposed as an energy-dissipation device to mitigate the structural seismic responses. It is simulated as a simplified nonlinear spring embedded in structural system with the force-displacement behavior derived by plate-beam theory. To investigate the effect of SPD, a typical 5-span high-speed railway simply supported bridge-track system (HSRSBTS) validated by a shaking table test is established by ANSYS. A novel damage measure, the system relative damage ratio (γSRD), is proposed to quantify the effect of SPD in the system and consider the potential component-level damage modes of both bending and shear. The structural system is investigated undergoing two ground motions suites in DBE- and MCE-level intensity, including both far-field and near-field records in transverse direction. The result indicates that a significant reduce (roughly 50%) of seismic response in rail and girder are contributed by SPD, while the system damage decreases about 10-15%, especially for near-field pulse-like ground motions with high intensity. The energy-dissipation capacity of SPDs with various configurations is examined to optimize the properties of SPD. It generally decreases with the increase in the elastic stiffness ratio r of the SPD to the fixed support, and the r = 2-2.5 are recommended in engineering practice. SPD is an effective and efficient device of structure to be adopted as an energy-dissipation component and the first defense line under far-field and near-field ground motions.

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Cyclic performance and shear resistance design of asymmetric diagonal stiffened beam-only-connected corrugated steel plate shear walls

Zheng Hong, Zhang Zhibin, Jiang Liqiang, Hu Yi, Wang Wei

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 4

art. no. e183, 2022

EN

The corrugated plate steel shear walls (CSPWs) are widely used as lateral force resistant members in high-rise buildings. However, buckling failure still easily occurred on corrugated steel plates subjected to earthquake loads, which is not good for the energy dissipation of structures. In this paper, the asymmetric diagonal stiffened beam-only-connected corrugated steel plate shear wall (ASW) is proposed. A test-validated FE modeling method is used to investigate the seismic performance of ASW, and the results are compared with the results of unstiffened corrugated steel plate shear wall (USW). Then parametric studies on the height-to-thickness ratio, wavelength, wave height of the corrugated plate and width-to-thickness ratio of the stiffeners are performed to investigate their effects on the seismic performance of ASW. Finally, a simplified theoretical model is developed to calculate the shear resistance of ASW, and the results are validated by tests and FE results. The results show that: (1) compared to the USW, the yield load and ultimate load of ASW increase 11.7% and 13.2%, respectively; (2) the theoretical calculation results are basically consistent with the FE and test results, and the errors between them are within ± 15%. These results can be used for seismic enhancement of CSPWs and seismic design of ASW.

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Seismic behavior and damage assessment of mid-rise cold-formed steel-framed buildings with normal and reinforced beam-column joints

Jiang Liqiang, Zhang Xingshuo, Ye Jihong, Jiang Lizhong, Zhou Lingyu

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 3

675--690

EN

This paper investigated the effects of normal and reinforced beam–column joints on seismic behavior and damages of mid-rise cold-formed steel (CFS) framed buildings, where the reinforced beam–column joint is strengthened by a pair of steel blocks and a gusset plate. Shaking table tests were conducted on a 5-story CFS frame building with normal beam-column joint (CFSM-NJ) and a 5-story CFS frame building with same configurations but with reinforced beam–column joint (CFSM-RJ). Formulae fitted from four damage models were used to assess the seismic damage indexes of these test buildings, and the assessed results were validated by the damage indexes observed from tests. The results show the following: (1) the CFSM-NJ failed due to plastic hinges formed at the column bases and large separate deformation at the beam-column joints; however, the weaken-story failure mode was appeared on the CFSM-RJ; (2) the peak inter-story displacement of the building was reduced about 10–30% due to the reinforced beam-column joints; (3) the Park-Ang model is more appropriate for seismic damage assessment of column bases, but all the damage models overestimates the seismic damages of CFS beams. Finally, the authors comment on the difference between the assessed seismic damage indexes and the observed results, and the maximum damage indexes obtained from the simplified formulae are recommended as the preliminary assessed damages for mid-rise CFS buildings.