Dynamic Structural Flexible-Beam Response to a Moving Barge Train Impact Force Time-History Using Impact-Beam.

摘要

To design simply-supported, flexible impact beams spanning between cells or bents for lock approach walls, a dynamic structural analysis of the beam under impact time-history loads for design- specific barge trains is required. At several locks, this flexible structural feature is the primary structural member resisting the glancing-blow impact event of a barge train as it aligns itself with a lock. This technical report describes an engineering methodology used to conduct this dynamic structural analysis and visualize the resulting deflections, moments, and shears. This engineering methodology is implemented with a PC-based FORTRAN program and visual modeler named Impact- Beam. The engineering formulation for Impact-Beam uses time-history force data that are scaled for design specific barge trains to perform a dynamic structural response analysis for either a single degree of freedom system or a modal timehistory analysis for the simply supported beam subjected to a impact load that is travelling along the beam. Time-history force data has been collected from the interpretation of the results from the 1997 full-scale barge train impact prototype experiments conducted at Old Lock and Dam 2 just north of Pittsburgh, PA, and of the 2008 full-scale barge train impact experiments conducted at Winfield Lock and Dam, Winfield, WV. This database of pulse time- history can be scaled for site specific design barge trains with approach angle and velocity using the companion software Impact-Force. It is also possible to use force time-histories from other impact simulation software (e.g., dBEAS). The engineering formulation for Impact-Beam is verified against the original Winfield experiments using modal time-history analysis and dBEAS simulations using single degree of freedom analysis.