Pre-Processor for Finite Element Analysis of Highway Bridges

Abstract

Historically, the lack of interactive pre-processors to setup tedious finite element problem descriptions has hindered the use of the finite element method for bridge analysis. The work performed in the present study mitigates this problem via the use of highspeed engineering workstations. This report presents an interactive, graphically based pre-processor for the analysis of highway bridges with the finite element method. With the pre- processor, bridge design engineers can use both keyboard and mouse styles of interaction to describe bridge geometries. The UNIX tool YACC has been used to create a command language for describing and manipulating of structural geometries, material types, loads, and boundary conditions. The pre-processor was successfully used to create input files in a format acceptable to the finite element analysis program ANSYS. In fact, less than 20 minutes was needed to create a finite element model of the prototype bridge tested at the Turner-Fairbanks Laboratory in Langley, Virginia, in a joint FHWA-AISI project. This report describes the development of the pre-processor in words that can hopefully be understood by civil engineers and computer scientists alike.