FEABAS A user friendly software for prediction of bridge approach settlement (FHWA-OK-95-03) 2188

Abstract

Bridge approach settlement is a major problem in highway design as well as maintenance. It creates an unsafe and uncomfortable riding surface. This report presents the details of a software that was developed at the University of Oklahoma, through a project funded jointly by the Oklahoma Department of Transportation (ODOT) and the Federal Highway Administration (FHW A). The objective of the software was to analyze the settlement characteristics of the problematic bridge approach sites in Oklahoma. To this end, a nonlinear Finite Element (FE) analysis procedure was developed for predicting the consolidation settlement of the foundation soil at a bridge approach due to the surcharge of embankment construction, as well as the settlement of the embankment itself due to the vehicular traffic loads. The software package , called FEABAS, is divided into a number of different modules: Preprocessor, Data Converter, FE Main Program, and Postprocessor. FEABAS works completely in the Windows operating environment in IBM compatible PC's. The interactive nature of the software makes it user-friendly; especially the graphical interface of the preprocessor enhances the data input operation. Existing data files can also be modified or edited using the preprocessor. The preprocessor is written in Actor 4.0 , which is a complete development environment and programming language that make it easy to develop stand-alone applications for Microsoft Windows Version 3.0 or later. This report presents an overview of the steps involved in analyzing bridge approach settlement using the software package. The software package - FEABAS is a very useful tool for conducting parametric studies of a problematic bridge approach site to identify some of the important causative factors and their relative significance, that are expected to be helpful in finding appropriate remedial measures to the problem. The bridge approach settlement at a site in Oklahoma was predicted using FEABAS for illustration and application. The various capabilities of the software including graphical output are illustrated.