Evaluation of Nonlinear Structural Dynamic Responses Using a Fast-Running Spring-Mass Formulation
It has been a fond desire of structural analysts to be able to calculate the dynamic responses of very large, highly nonlinear systems without expending a year’s allocation of computer funds with every run. In today’s world, accurate finite-element simulations of large nonlinear systems may require meshes composed of hundreds of thousands of degrees of freedom. Even with today’s fast computers and the promise of ever-faster ones in the future, central processing unit (CPU) expenditures for such problems could be measured in days. Many contemporary engineering problems, such as those found in risk assessment, probabilistic structural analysis, and structural design optimization, cannot tolerate the cost or turnaround time for such CPU-intensive analyses, because these applications require a large number of cases to be run with different inputs. For many risk assessment applications, analysts would prefer running times to be measurable in minutes. There is therefore a need for approximation methods which can solve such problems far more efficiently than the very detailed methods and yet maintain an acceptable degree of accuracy. For this purpose, we have been working on two methods of approximation: neural networks and spring-mass models.
KeywordsFoam Strain Hardening Flange
Unable to display preview. Download preview PDF.
- A. S. Benjamin and B. S. Altman, Spring-mass Transient Response Evaluation for Structural Systems (STRESS), Users Manual, Sandia National Laboratories, Albuquerque, NM, report to be published.Google Scholar
- P3/PATRAN User Manual, Publ. No. 903000, PDA Engineering PATRAN Division, Costa Mesa, CA, 1992.Google Scholar
- V. K. Gabrielson and R. T. Reese, SHOCK Code User’s Manual, A Computer Code to Solve the Dynamic Response of Lumped-Mass Systems, Report SCL-DR-69–98, Sandia National Laboratories, Albuquerque, NM, 1969.Google Scholar
- W. C. Mills-Curran, A. P. Gilkey, and D. P. Flanagan, EXODUS: A Finite Element File Format for Pre- and Postprocessing, Report SAND87–2997, Sandia National Laboratories, Albuquerque, NM, 1992.Google Scholar
- G. D. Sjaardema, Overview of the Sandia National Laboratories Engineering Analysis Code Access System, Report SAND92–2292, Sandia National Laboratories, Albuquerque, NM, 1993.Google Scholar
- A. P. Gilkey and J. H. Glick, BLOT — A Mesh and Curve Plot Program for the Output of a Finite Element Analysis, Report SAND88–1432, Sandia National Laboratories, Albuquerque, NM, 1989.Google Scholar
- J. D. Gruda, The Dynamic Response of a Weapon’s Internal Components to a High Speed Impact, ASME/JSME Pressure Vessel and Piping Conference, Honolulu, HI, July 1995.Google Scholar