Technical Reports

FRATE, Volume I: User's Manual

  • 01
  • Sep
  • 1978
AUTHOR: G. Kachadourian, N. W. Sussman, J. R. Anderes
SUBJECT: Facilities & Test Equipment
KEYWORDS: Freight Car Response Analysis and Test Evaluation, Freight Car Vibration Analysis, TOFC, Dynamic Response, Computer Program
ABSTRACT: FRATE (Freight Car Response Analysis and Test Evaluation) is the name of a digital computer program which numerically solves the structural dynamic equations of motion of a single railroad freight car excited by wheel/rail interface motions. The Federal Railroad Administration (FRA) has sponsored its development for the purpose of applying it to freight car analysis and test problems. This manual has been written with the objective of providing the user with all of the detailed information needed as concisely and accessibly as possible. To this end the manual has been divided into two volumes: Volume I is a User's Manual containing basic user related information, Volume II is a Technical Manual containing more detailed technical information. FRATE is written to allow the simulation of a broad range of freight cars by only simple input data changes. A Trailer-on-Flatcar (TOFC) configuration is simulated in this manual. FRATE solves the equations of motion in the time domain and includes the following features; (1) nonlinearities which presently include separations, bilinear springs and no small angle assumptions, (2) five degree-of- freedom coordinate coupling (longitudinal motions have been omitted), (3) normal mode structural flexibility and (4) frequency response from simulated sweep testing. Although it has not been included in this report coulomb damping has been included and used in a trial version of FRATE.