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RT-Frame2D: A Computational Platform for the Real-Time Hybrid Simulation of Dynamically-excited Steel Frame Structures

RT-Frame2D: A Computational Platform for the Real-Time Hybrid Simulation of Dynamically-excited Steel Frame Structures

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Version 1.0 - published on 30 Jul 2012

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A newly-developed computational tool RT-Frame2D for performing real-time hybrid simulation of seismically-excited nonlinear steel frame structures is introduced. RT-Frame2D is proposed as one of the main components of a small-scale real-time hybrid simulation (RTHS) platform recently developed in the Intelligent Infrastructure Systems Laboratory (IISL) at Purdue University. The tool is developed and implemented within the context of a MATLAB /Simulink environment with a MATLAB/Embedded subset function format (The Mathworks, 2009) to enable both its easy integration with remaining RTHS components and execution under a real-time kernel platform. Several modeling features required to capture the nonlinear behavior usually observed in steel frames when subjected to ground motion are available in RT-Frame2D. Mass is modeled with a concentrated-lumped scheme. Damping can be represented with either a mass/stiffness proportional damping or a Rayleigh damping modeling options. Linear and nonlinear beam-column elements with optional transverse shear effects are available. Nonlinear beam-column elements can be represented by two schemes. A moment-curvature type nonlinear element that represents material nonlinearity either with a spread plasticity model (SPM) or a concentrated plasticity model (CPM). Additionally, a moment-rotation type linear elastic beam-column element with nonlinear connections is also available. Bilinear and tri-linear steel material models with kinematic hardening can be selected. Panel zone effects are accounted by a new model proposed by Hjelmstad and Haikal (Hjelmstad, 2006). Two versions are currently available: a rigid-body version and a linear version with bidirectional tension/compression and shear distortion effect. Global second order effects (P-Delta effects) are accounted by the geometric stiffness matrix approach. Two integration schemes are available for solving the equation of motion and evaluate the nonlinear dynamic response; the explicit-unconditionally stable Chen-Ricles (CR) algorithm (Chen and Ricles, 2008) and the implicit-unconditionally stable Newmark-Beta method with constant acceleration (Newmark, 1959).



The RT-Frame2D software has been extensively evaluated through comparison with well-known simulation platforms for nonlinear analysis of frame structures, and validated when subjected to several real-time hybrid simulations scenarios. However, the software is provided "AS IS", without warranty of any kind, express or implied, on the accuracy or performance under certain modeling assumptions or experimental conditions. The user is responsible for understanding the limitations and theoretical background associated with each of the modeling capabilities prior to use.


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Nestor Castaneda

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Financial support for these efforts has been provided in part by the National Science Foundation under grants CMMI-1011534 (NEESR) and CNS-1028668 (MRI), as well as Purdue University's Cyber Center Special Incentive Research Grant (SIRG).


Castaneda, N (2012). Development and Validation of a Real-time Computational Framework for Hybrid Simulation  of Dynamically-excited Steel Frame Structures. Ph.D. Dissertation. School of Civil Engineering, Purdue University

Chen, W. F. and Kishi, N. (1989). Semi-rigid steel beam-to-column connections: Database and modeling. J. Struct. Engng. ASCE, 115(1), pp. 105-119.

Chen, C. and Ricles, J. M. (2008). Development of Direct Integration Algorithms for Structural Dynamics using Discrete Control Theory. Journal of Engineering Mechanics. 134, no. 8: 676-683.

ETABS User's Manual, Computers and Structures Inc., Berkeley, CA. 1988.

El-Tawil, S.,Vidarsson E., Mikesell, T. and Kunnath, K. (1999). "Inelastic behavior and design of steel panel zones". Journal of Structural Engineering, 125, 2, Feb. 1999, pages 183-193.

Galambos, T. V. (1988). "Guide to Stability Design Criteria for Metal Structures". 4th Ed., John Wiley & Sons, New York, NY, USA.

Geschwindner, L. F. (1994). "A practical approach to the ‘leaning’ column." Eng. J., 31_4_, 141–149.

Giberson, M.F. (1967). The response of nonlinear multistory structures subjected to earthquake excitation. Ph.D. Dissertation, Caltech.

Hilmy, S. I., and Abel, J. F. (1985). ‘‘A strain-hardening concentrated plasticity model for nonlinear dynamic analysis of steel buildings.’’ Proc., NUMETA85, Numerical Methods in Engineering, Theory and Applications, 1, 303–314.

Hjelmstad, K.D. and Haikal, G. (2006). "Analysis of Steel Moment Frames with Deformable Panel Zones". Steel Structures, 2006, pages 129-140

Iwan, W.D. (1961). "The Dynamic Response of Bilinear Hysteretic Systems". California Institute of Technology Reports (No longer available)

Kanaan, A. E. and Powell, G.H. (1973), "DRAIN-2D A General Purpose Compute Program for Dynamic Analysis of Inelastic Plane Structures", Reports No. UCB/EERC/73/06 and 73/22. University of California, Berkeley.

Kunnath, S. K., Reinhorn, A. M., and Lobo, R. F. (1992). "IDARC Version 3.0: A Program for the Inelastic Damage Analysis of Reinforced Concrete Structures". Report No. NCEER-92-0022, National Center for Earthquake Engineering Research, State University of New York at Buffalo.

Lobo, R.F. (1994). Inelastic Dynamic Analysis of Reinforced Concrete Structures in Three Dimensions. Ph.D. Dissertation, Dept. of Civil Engrg. New York State University at Buffalo.

Mckenna, F. and Fenves, G.L. (2002). " The OpenSees command language primer". Department of Civil and Environmental Engineering, University of California, Berkeley, CA.

Mckenna, F., Fenves, G.L. and Scott, M.H. (2002). "Open system for earth-quake enginnering simulation, http:/". Pacific Earthquake Engineering Research Center, University of California, Berkeley, CA. 

Newmark, N.M. (1959) "A method of computation for structural dynamics" Journal of Engineering Mechanics Division, ASCE, Vol. 85, pp.67–94.

George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES)

Ohtori, Y. and Spencer, B.F., Jr. (1999). "A MATLAB-Based Tool for Nonlinear Structural Analysis", In the Proceedings of the 13th ASCE Engineering Mechanics Division Specialty Conference, Johns Hopkins University, Baltimore, June 13-16.

Ohtori, Y., Christenson, R.E., Spencer, B.F. and Dyke, S.J. (2004). "Nonlinear Benchmark Control Problem for Seismically Excited Buildings". ASCE Journal of Engineering Mechanics, 130(4), pp.366-385,2004


Park, Y. J., Reinhorn, A. M., and Kunnath, S. K. (1987), IDARC: Inelastic Damage Analysis of Reinforced Concrete Frame - Shear-Wall Structures, Technical Report NCEER-87-0008, State University of New York at Buffalo.

Spacone, E., Filippou, F. C., and Taucer, F. F. (1996a). ‘‘Fiber beam-column model for nonlinear analysis of R/C frames. Part I: Formulation.’’ Earthquake Eng. Struct. Dyn., 25~7, 711–742.

Spacone, E., Filippou, F. C., and Taucer, F. F. (1996b). ‘‘Fiber beam column model for nonlinear analysis of R/C frams. Part II: Application.’’ Earthquake Eng. Struct. Dyn., 25~7, 728-742.

Scott, M.H. and G.L. Fenves. "Plastic Hinge Integration Methods for Force-Based Beam-Column Elements", Journal of Structural Engineering, ASCE, 132(2):244-252, February 2006.

Subbaraj, K. and Dokainish, M.A. (1989). "A Survey of Direct Time-Integration Methods in Computational Structural Dynamics - II. Implicit Method." Computers and Structures, Vol.32, No.6, pp.1387–1401.

The MathWorks. (2009):

Valles, R.E., Reinhorn, A.M., Kunnath, S.K., Li, C. and Madan, A. (1996). "IDARC2D Version4.0: A Computer Program for the Inelastic Damage Analysis of the Buildings." Technical Report NCEER-96-0010, Nat. Ctr. for Earthquake Engrg. Res., Buffalo, New York.  

Wilson, E.L. and Habibullah, A. (1987). "Static and Dynamic Analysis of Multi-story Buildings including P-Delta Effects," Earthquake Spectra Journal, EERI, Vol. 3, No.2, pp.289-298.


Castaneda, N (2012). Development and Validation of a Real-time Computational Framework for Hybrid Simulation of Dynamically-excited Steel Frame Structures. Ph.D. Dissertation. School of Civil Engineering, Purdue University

Cite this work

Researchers should cite this work as follows:

  • Nestor Eduardo Castaneda-Aguilar; Xiuyu Gao; Shirley Dyke (2012), "RT-Frame2D: A Computational Platform for the Real-Time Hybrid Simulation of Dynamically-excited Steel Frame Structures,"

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