Finite Element Analysis of MR Elastomers in Steel Structures as Dampers with Seismic Loading

During the Northridge earthquake of 1994, many steel structures collapsed as a result of the connection failures in the structure. After investigation, it was concluded that the connections in the steel structure, including the column base connection, have to be made stronger and to be able to dissipate energy during seismic motion. To facilitate that, a new kind of damper system having Magnetorheological Elastomers (MRE) as the damping material is proposed here. MRE was taken because of its ability to dissipate energy and provide extra stiffness when needed. The damper system along with the column base connection was then modelled, and modal, harmonic and transient analyses were performed on the model using Finite Element Analysis in ANSYS. The results showed that MRE successfully decreased the moment reaction at the connection, making it more reliable during strong earthquakes. The analyses were performed with prescribed loading by SAC, and El Centro ground motion, and in both the cases the designed damper system showed its capability of dissipating energy. It was also seen that with MRE as damper, the natural frequency of the connection can also be controlled, which can prove useful in certain cases. A parametric study was then conducted to see how the effect varies with different material and physical parameters of MRE.

[1]  John Matthew Ginder,et al.  Magnetorheological elastomers in tunable vibration absorbers , 2001, SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring.

[2]  Michel Bruneau,et al.  Performance of steel structures during the 1994 Northridge earthquake , 1995 .

[3]  T. T. Soong,et al.  Seismic response of steel frame structures with added viscoelastic dampers , 1989 .

[4]  Mehdi Setareh,et al.  Pendulum Tuned Mass Dampers for Floor Vibration Control , 2006 .

[5]  Akshay Gupta,et al.  Dynamic P-Delta Effects for Flexible Inelastic Steel Structures , 2000 .

[6]  Tak-Ming Chan,et al.  Seismic performance of beam–column joints with SMA tendons strengthened by steel angles , 2015 .

[7]  R. Li,et al.  Dynamic viscoelastic modeling of magnetorheological elastomers , 2014 .

[8]  J. Carlson,et al.  A model of the behaviour of magnetorheological materials , 1996 .

[9]  S. K. Dwivedy,et al.  Multi-frequency excitation of magnetorheological elastomer-based sandwich beam with conductive skins , 2012 .

[10]  Nong Zhang,et al.  Semi-active variable stiffness vibration control of vehicle seat suspension using an MR elastomer isolator , 2011 .

[11]  Holger Böse,et al.  Soft magnetorheological elastomers as new actuators for valves , 2012 .

[12]  DAvm M. BooR.  Bulletin of the Seismological Society of America , 2005 .

[13]  Weihua Li,et al.  Development of a force sensor working with MR elastomers , 2009, 2009 IEEE/ASME International Conference on Advanced Intelligent Mechatronics.

[14]  A. Bower.  Applied Mechanics of Solids , 2009 .

[15]  Tomi Lindroos,et al.  Dynamic compression testing of a tunable spring element consisting of a magnetorheological elastomer , 2007 .

[16]  H. Du,et al.  A dynamic absorber with a soft magnetorheological elastomer for powertrain vibration suppression , 2009 .

[17]  Larry Dean Elie,et al.  Controllable-stiffness components based on magnetorheological elastomers , 2000, Smart Structures.

[18]  S. W. Park,et al.  Methods of interconversion between linear viscoelastic material functions. Part I-a numerical method based on Prony series , 1999 .

[19]  Xinglong Gong,et al.  Development of a real-time tunable stiffness and damping vibration isolator based on magnetorheological elastomer , 2012 .

[20]  Huaxia Deng,et al.  Development of an adaptive tuned vibration absorber with magnetorheological elastomer , 2006 .

[21]  Amit Kanvinde,et al.  Column Base Connections for Hollow Steel Sections: Seismic Performance and Strength Models , 2015 .

[22]  Zhao-Dong Xu,et al.  Experimental and Modeling Study on Magnetorheological Elastomers with Different Matrices , 2013 .

[23]  Billie F. Spencer,et al.  “Smart” Base Isolation Strategies Employing Magnetorheological Dampers , 2002 .

[24]  Xinglong Gong,et al.  An effective permeability model to predict field-dependent modulus of magnetorheological elastomers , 2006 .

[25]  R. Ogden.  Non-Linear Elastic Deformations , 1984 .