SKEW GIRDER BRIDGE ANALYSIS

Abstract

This dissertation mainly deals with the study of arplication and suitability of Harmonics Method(Modified Hendry-Jaeger Method) for analyzing skew or right Girder Bridges. This has been achieved through a typical example of a 4-Girder Skew Bridge having skew'span 19.4m, skew angle 40° and carriage width 7.5 m, wherein the main girders of;the bridge have been analyzed in detail for Dead. Load Mooents and Live Load Moments under the two typical configurations of IRO class A loading. With the help of computations carried out, it has been demonstrated that the method is quite effective and efficient for analyzing girder bridges. Attempts have also been made herein, to bring out quite lucidly the basic principles involved in the theoretical formu-lation of this method. The study of this theoretical part leads to a clear understanding of the structural behaviour of girder bridges. The limitations and difficulties associated with the application of the computer based methods such as Finite Element Method and other conventional methods such as Courbon's method and Guyon's method to the analysis of girder bridges have been briefly indicated. The mathematical model for Design coefficientFalong with girder moment expressions for different loading cases have been discussed so as to back up the various steps of systematic computation Procedure developed with theoretical reasoning. iv The significance of various dimensionless structural parameters in the distribution of imposed loading amongst the girders has been briefly explained. For the applicability of moment expressions, the imposed loads'on the deck have been converted into equivalent system of loads on all the girders of the bridge deck.