Table 1: Elastomeric Bearings : Limit states and threshold values
(R): limit state definition based on soa ,(E): Experimental, (S): Simulation or analysis
| Engineering Demand Parameter: Shear deformation γ (%) | |||
|---|---|---|---|
| Reference | Limit State | Shear deformation (γ) | Description |
| . (E) Mori, A., Moss, P.J., Carr, A. J., Cooke, N. (1997) https://dx.doi.org/10.12989/sem.1997.5.4.451 | LS1 | 150% | Yielding of steel plates |
| LS4 | 300% | Bearing failure | |
| . (E) Bousias, E., Palios, X., Alexakis Ch., Strepelias, E., Fardis, M., Raptopoulos, S. (2008) | LS3 | 150% | Detachment of elastomers and steel plates |
| . (R) Cardone, D. (2013) https://doi.org/10.1002/eqe.2396 | LS1 | 150%, bolted pads γ(dfr), slipping unbolted pads γ(dpad/3), rolling-over unbolted pads | Slipping between neoprene pads and concrete surfaces |
| LS2 | 200%, bolted pads γ(dfr+1/3(dpad-dfr)), slipping unbolted pads γ(dpad/2), rolling-over unbolted pads | Shear deformation limit for linear viscoelasticbehvior of bolted neoprene pads | |
| LS3 | 300%, bolted pads γ(dpad), slipping unbolted pads γ(dpad), rolling-over unbolted pads | Rubber shear failure (bolted pads), slipping between neoprene concrete surface and roll-over (unbolted pads) | |
| LS4 | duns | Unseating | |
| . (E) Konstantinidis et al. (2008) | LS3 | 150%-225% | Roll-over |
| . (E) LaFave et al. (2013) | LS1 | 53-85% | Tension/shear failure of anchors |
| LS2 | 100-200% | Initiation of slipping | |
| LS4 | 400% | Unseating | |
| . (E) Mori, A., Moss, P.J., Cooke, N., Carr, A. J. (1999) https://doi.org/10.1193%2F1.1586038 | LS3 | 200% | Bearing Uplift |
| . (E) Mori, A., Moss, P.J., Carr, A. J., Cooke, N. (1997) https://dx.doi.org/10.12989/sem.1997.5.4.451 | LS2 | 106-150% | Yielding of steel plates |
| . Moschonas, I. F., Kappos, A. J., Panetsos, P., Papadopoulos, V., Makarios, T., Thanopoulos, P. (2009) https://doi.org/10.1007/s10518-008-9077-2 | LS1 | 20% | Minor damage |
| LS2 | 150% | Moderate damage | |
| LS3 | 200% | Major damage | |
| LS4 | 500% | Stability failure (toppling) | |
| . (E) Nielson, B. (2005) | LS1 | γ(Δ=30 mm), long. & transv. | Deformation of slight damage |
| LS2 | γ(Δ=100 mm), long. & transv. | Possible dowel fracture | |
| LS3 | γ(Δ=150 mm), long. & transv. | Dowel fracture, repair requirement | |
| LS4 | γ(Δ=255 mm), long. & transv. | Unseating | |
| . (S) Stefanidou S. & Kappos A.(2017) https://doi.org/10.1002/eqe.2774 | LS1 | 20% | Initiation of nonlinear behaviour (yielding displacement of piers), potential yielding of anchor bolts and cracking of pedestals. |
| LS2 | 100% | Visible damage to the bearing; yield of steel shims | |
| LS3 | 200% | Lift off at the edge of the bearing, uplift and rocking; may cause delamination, bonding failure between rubber layers and steel shim plates | |
| LS4 | 300% | Lift-off, rotation; unseating, failure of bearings. | |
| . (S+R) Zhang, J. and Huo, Y. (2009) https://doi.org/10.1016/j.engstruct.2009.02.017 | LS1 | 100% | Slight damage (strain limit for linear behavior of rubber) |
| LS2 | 150% | Moderate damage | |
| LS3 | 200% | Extensive damage (Initiation of hardening of elastomeric material) | |
| LS4 | 250% | Complete damage (significant pounding or unseating) | |
References
- Aviram, A., Mackie, K. R., Stojadinovic, B. (2008). Effect of abutment modeling on the seismic response of bridge structures, Earthquake Engineering and Engineering Vibration, Vol. 7, No. 4, pp 395 – 402, DOI: https://doi.org/10.1007/s11803-008-1008-3.
- Bousias, E., Palios, X., Alexakis, C., Strepelias, I., Fardis, M., Raptopoulos, S. (2008). Experimental and analytical study of seismically isolated bridges with or without additional damping, 3rd Hellenic Conference on Earthquake Engineering and Engineering Seismology, November 5-7, 2008 (in Greek).
- Cardone, D. (2013). Displacement limits and performance displacement profiles in support of direct displacement-based seismic assessment of bridges, Earthquake Engineering & Structural Dynamics, DOI: http://dx.doi.org/10.1002/eqe.2396.
- Konstantinidis, D., J.M. Kelly, and N. Makris. (2008). Experimental Investigations on the Seismic Response of Bridge Bearings, Earthquake Engineering Research Center, Report No. EERC 2008-02, College of Engineering, University of California, Berkeley, CA.
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- Mori, A., Moss, P. J., Cooke, N., Carr, A. J. (1999). The Behavior of Bearings Used for Seismic Isolation under Shear and Axial Load, Earthquake Spectra, Vol. 15, No. 2, pp 199-224, https://doi.org/10.1193%2F1.1586038.
- Mori, A., Moss, P. J., Carr, A. J., Cooke, N. (1997). Behaviour of laminated elastomeric bearings, Structural Engineering and Mechanics, Vol. 5, No. 4, pp 451-469, DOI: http://dx.doi.org/10.12989/sem.1997.5.4.451.
- Moschonas, I. F., Kappos, A. J., Panetsos, P., Papadopoulos, V., Makarios, T., Thanopoulos, P. (2009). Seismic fragility curves for Greek bridges: methodology and case studies, Bulletin of Earthquake Engineering, Vol. 7, pp 439-368, https://doi.org/10.1007/s10518-008-9077-2.
- Nielson, B. G. (2005). Analytical Fragility Curves for Highway Bridges in Moderate Seismic Zones, PhD Thesis, Georgia Institute of Technology, December, 2005.
- Stefanidou, S. & Kappos A. (2017). Methodology for the development of bridge-specific fragility curves, Earthquake Engineering and Structural Dynamics, vol. 46, pp 73-93, https://doi.org/10.1002/eqe.2774.
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