The Earthquake Engineering Online Archive

Dynamic analysis of nonlinear structures using state-space formulation and partitioned integration schemes

Inaudi, Jose A.; Llera, Juan Carlos de la

UCB/EERC-92/18, Earthquake Engineering Research Center, University of California, Berkeley, 1992-11, 96 pages (555.3/I53/1993)

This report is divided into four chapters and three appendices. Chapter 2 develops the mathematical model used for representing dynamic systems, i.e., the transition between the second-order differential equations of motion and the first-order state space equations, as well as the numerical integration strategy employed to solve the equations of motion of the system. Chapter 3 presents an analysis of the stability of the integration method proposed. The boundaries of stability of the method are studied and briefly compared with the Newmark integration procedure. Chapter 4 presents a prototype-program implementation of the approach developed in Chapter 2; emphasis is more on the generality of the approach--shown through several examples--than on the program itself. Since the program has been implemented as a set of subroutines in MATLAB, it is mainly intended for education and research and not for the solution of large practical structures. Appendix A contains a brief User Manual for the program. Appendix B describes the mechanical elements that have been incorporated into the program, and Appendix C summarizes some mathematical derivations used in Chapter 2 that are not readily available in the literature.

Available online: http://nisee.berkeley.edu/documents/EERC/EERC-92-18.pdf (5 MB)