Numerical study on the end rotation effect of elastomeric bearings on their mechanical behavior in flexible bridges

Document Type : Research Article


1 Associate Prof.

2 MSc, Dept. of Civill Engg, Amirkabir University Tehran, Iran


When elastomeric bearings support the deck of long-spans or tall pier bridges, they experience end rotation and it can change the seismic performance of the whole isolated system. So far, the behavior of these bearings has been numerically modeled under individual actions (compression, shear, or bending) or combined compression and shear load. However, the effect of end rotation on the response of elastomeric bearings and its numerical model in combination with different load actions have not been considered well. In the current study, we used a two-dimensional mechanical model of elastomeric bearings that simulate the effect of end rotation in the combined action of pressure, shear and end rotation. The test results indicate that bearing rotational stiffness increases with the increasing vertical load but decreases with increasing shear deformation. Further, end rotation does not affect the critical displacement appreciably, but it significantly influences the critical shear force.


Main Subjects

[1] I.G. Buckle, J.M. Kelly, Properties of slender elastomeric isolation bearings during shake table studies of a large-scale model bridge deck, Special Publication, 94 (1986) 247-270.
[2] I.G. Buckle, H. Liu, Stability of elastomeric seismic isolation systems, in:  Proc. of Seminar on Seismic Isolation, Passive Energy Dissipation and Control, 1993, Applied Technology Council, 1993.
 [3] J. Sanchez, A. Masroor, G. Mosqueda, K. Ryan, Static and dynamic stability of elastomeric bearings for seismic protection of structures, Journal of structural engineering, 139(7) (2012) 1149-1159.
[4] P. Hakimian, T. Taghikhany, Master Thesis, Verification of High Damping Rubber Bearing Assembled in Iran with Finite Element Simulation, Amirkabir University of Technology, Tehran, Iran, (2017) . 
[5] A.P. Crowder, T.C. Becker, NDM-518: Effects of Non-Traditional Isolator Placement For Seismic Retrofit,  (2016).
[6] A. Karbakhsh Ravari, I. Bin Othman, Z. Binti Ibrahim, K. Ab-Malek, P-Δ and end rotation effects on the influence of mechanical properties of elastomeric isolation bearings, Journal of Structural Engineering, 138(6) (2012) 669-675.
[7] Z. Xu, X. Zhu, C. Deng, End Rotation Effects of Horizontal Mechanical Properties of Rubber Bearings, DEStech Transactions on Engineering and Technology Research, (icaenm) (2017).
[8] S.R. Moghadam, D. Konstantinidis, Ph.D, Thesis, Effect of Support Conditions on the Behavior of Elastomeric Bearings, McMaster University, McMaster University, Hamilton, Ontario, Canada, (2017).
[9] S.R. Moghadam, D. Konstantinidis, Finite element study of the effect of support rotation on the horizontal behavior of elastomeric bearings, Composite Structures (2017) 163, 474-490
[10] SR Moghadam, D Konstantinidis, Simple mechanical models for the horizontal behavior of elastomeric bearings including the effect of support rotation Engineering Structures (2017) 150, 996-1012
[11] S.R. Moghadam, D. Konstantinidis, Experimental and Analytical Studies on the Horizontal Behavior of Elastomeric Bearings under Support Rotation, Journal of Structural Engineering,( 2021), 147 (4),
 [12] C.G. Koh, J.M. Kelly, A simple mechanical model for elastomeric bearings used in base isolation, International journal of mechanical sciences, 30(12) (1988) 933-943.
[13] M. Iizuka, A macroscopic model for predicting large-deformation behaviors of laminated rubber bearings, Engineering structures, 22(4) (2000) 323-334.
 [14] S. Yamamoto, M. Kikuchi, M. Ueda, I.D. Aiken, A mechanical model for elastomeric seismic isolation bearings including the influence of axial load, Earthquake Engineering & Structural Dynamics, 38(2) (2009) 157-180.
 [15] K. Ishii, M. Kikuchi, T. Nishimura, C.J. Black, Coupling behavior of shear deformation and end rotation of elastomeric seismic isolation bearings, Earthquake engineering & structural dynamics, 46(4) (2017) 677-694.