Evaluating the Effect LRB Isolators in Retrofitting a Truss Bridge
Subject Areas : Structural Mechanics
majid moradi
1
*
,
sepide rahimi
2
,
Sadegh Rezaei
3
,
nima ranjbar
4
1 - Assistant Professor, University of Science and Technology of Mazandaran
2 - Department of Civil Engineering, No.C., Azad University, Noor, Iran
3 - Assistant Professor, University of Science and Technology of Mazandaran
4 - Department of Civil Engineering, No.C., Azad University, Noor, Iran
Keywords: Truss bridge, seismic isolator, seismic performance, fragility curve, retrofitting,
Abstract :
One of the things used to equip and strengthen bridges is the addition of a seismic isolator. In this study, the seismic performance of a truss bridge equipped with a seismic isolator has been evaluated. Thus, two structural models of a truss bridge have been modeled nonlinearly in the Perform software. One is the initial and main model and the other has a seismic isolator. Initially, using incremental dynamic analysis, seismic parameters such as the horizontal displacement of the superstructure, the hysteresis curve and the time history of the moment applied to the column, the horizontal displacement of the column head and the hysteresis curve of the models have been investigated. Finally, the incremental dynamic curves and the fragility of the structures have been investigated and compared using twenty earthquake records. The results show that the use of an isolator reduces the horizontal displacement of the bridge column and reduces the probability of its collapse at different accelerations and different performance levels.
[1] Hosseinlou, F., Moradi, M., Sadrianzade, M., & Jalali, P. (2025). An energy-based method for calculating the fragility curve of bridges: a case study. Iranian Journal of Science and Technology, Transactions of Civil Engineering, 1-26.
[2] Moradi, M., & Tavakoli, H. (2020). Proposal of an energy based assessment of robustness index of steel moment frames under the seismic progressive collapse. Civil Engineering Infrastructures Journal, 53(2), 277-293.
[3] Azizinamini, A., Full scale testing of old steel truss bridge. Journal of constructional steel research, 2002. 58(5-8): p. 843-858.
[4] Mousavi, A.A., et al., Structural damage localization and quantification based on a CEEMDAN Hilbert transform neural network approach: a model steel truss bridge case study. Sensors, 2020. 20(5): p. 1271.
[5] Zhou, X., et al., Vibration-based Bayesian model updating of an actual steel truss bridge subjected to incremental damage. Engineering Structures, 2022. 260: p. 114226.
[6] Pham, N.V., et al., Seismic Retrofit of Diagonal Tension Members in Steel Deck-Truss Bridges Using CFRP Sheets. Journal of Composites for Construction, 2023. 27(3): p. 04023023.
[7] Chen, X., et al., Performance-Based Retrofits of Long-Span Truss Bridges Based on the Alternate Load Path Redundancy Analysis. Journal of Bridge Engineering, 2023. 28(2): p. 04022141.
[8] Sosorburam, P. and E. Yamaguchi, Seismic retrofit of steel truss bridge using buckling restrained damper. Applied Sciences, 2019. 9(14): p. 2791.
[9] Hanai, T., T. Tamura, and Y. Hirayama, Seismic retrofit of truss bridge for highway and railway, in Maintenance, Safety, Risk, Management and Life-Cycle Performance of Bridges. 2018, CRC Press. p. 1944-1950.
[10] Li, S., et al., Performance-based seismic loss assessment of isolated simply-supported highway bridges retrofitted with different shape memory alloy cable restrainers in a life-cycle context. Journal of Intelligent Material Systems and Structures, 2020. 31(8): p. 1053-1075.
[11] Deb, S.K., Seismic base isolation–An overview. Current Science, 2004: p. 1426-1430.
[12] Yang, Y., L. Lu, and J. Yau, Structure and equipment isolation, in Vibration and Shock Handbook. 2005, CRC Press. p. 22.
[13] Moradi, M., Tavakoli, H., & Abdollahzadeh, G. R. (2022). Collapse probability assessment of a 4-Story RC frame under post-earthquake fire scenario. Civil Engineering Infrastructures Journal, 55(1), 121-137.
[14] Kulicki, J.M. Past, Present, and Future of Load and Resistance Factor Design- AASHTO LRFD Bridge Design Specifications. in 6 th International Bridge Engineering Conference. 2005.
[15] Bridges, S.o., S. Staff, and T.O.S.o. Bridges, Guide specifications for seismic isolation design. 2010: AASHTO.
[16] Mojiri, S., W.W. El-Dakhakhni, and M.J. Tait, Seismic fragility evaluation of lightly reinforced concrete-block shear walls for probabilistic risk assessment. Journal of Structural Engineering, 2015. 141(4): p. 04014116.
[17] Moradi, M. and M. Abdolmohammadi, Seismic fragility evaluation of a diagrid structure based on energy method. Journal of Constructional Steel Research, 2020. 174: p. 106311.
[18] Moradi, M., Tavakoli, H., & Abdollahzade, G. (2024). Probabilistic evaluation of failure time of reinforced concrete frame in post‐earthquake fire scenario. Structural Concrete, 25(5), 3487-3504.
[19] Goodarzi, M. J., Moradi, M., Jalali, P., Abdolmohammadi, M., & Hasheminejad, S. M. (2023). Fragility assessment of an outrigger structure system based on energy method. The Structural Design of Tall and Special Buildings, 32(11-12), e2017..
[20] Moradi, M., H. Tavakoli, and G. AbdollahZade, Sensitivity analysis of the failure time of reinforcement concrete frame under postearthquake fire loading. Structural Concrete, 2020. 21(2): p. 625-641.
[21] Tavakoli, H. and M.M. Afrapoli, Robustness analysis of steel structures with various lateral load resisting systems under the seismic progressive collapse. Engineering Failure Analysis, 2018. 83: p. 88-101.
[23] Li, S. Q., Liu, H. B., Farsangi, E. N., & Du, K. (2025). Seismic fragility estimation considering field inspection of reinforced concrete girder bridges. Structure and Infrastructure Engineering, 21(2), 302-318.
[24] de Silva, D., Miano, A., De Rosa, G., Di Meglio, F., Prota, A., & Nigro, E. (2025). Analitycal fire fragility assessment for bridges considering fire scenarios variability. Engineering Structures, 325, 119442.
[25] Lian, Q., Chen, L., Dang, X., Zhuo, W., & Li, C. (2025). Dynamic response and fragility of mountain bridges under the coupled effects of transverse earthquakes and landslides. Soil Dynamics and Earthquake Engineering, 188, 109079.
[26] Yan, B., Lai, J., Wu, S., Feng, S., & Meng, X. (2025). Seismic fragility assessment of UHPC ribbed arch bridges. Soil Dynamics and Earthquake Engineering, 190, 109199.
[27] Kumar, V., Singh, V., & Shekhar, S. (2025). Mainshock-Aftershock Ground Motion Sequences Selection and its Implication on Bridge Seismic Fragility. Journal of Earthquake Engineering, 1-24.