Aspects of analysis of simply supported bridge decks

Abstract

Bridge analysis is a process in which one determines the responses of structures due to load effects. The responses usually constitute of deflections, torsions, support reactions, bending moments and shear forces. The analysis can be done based on the types of decks and the characteristic behaviours of the bridge structure itself. There are several types of analysis that can be used to analyze the bridge deck structure. However, it is difficult in terms of the suitability to select the method that is most appropriate for a particular problem. This study is conducted in order to evaluate the common methods of bridge deck analysis and to compare the performance between each type of analysis either by using the manual calculation or software analysis. The focus of this study is on the grillage method of analysis and the finite element method of analysis. Subsequently, the method of analysis that can yields suitable and better results is proposed. One structural form of bridge deck in varying skewness and simply supported has been chosen as the case study. This deck is analyzed using the commercially available software called LUSAS. The results show that the finite element method yields lower values than the grillage method. On the other hand, the values of responses whether deflection, bending moment, shear force, support reaction and torsion decrease as the skewness of the bridge deck increases. Based on these findings, it can be concluded that the finite element method can offer better and suitable results especially with the advent of software and computer technology nowadays.