Analysis And Design of Curved Steel Tub Girder Bridge

Abstract

Now a days, the frequency of use of steel bridges has increased in practice. Composite steel concrete plate girder and box girder are commonly used in curved bridges, ramps and interchanges. Composite steel tub girder is particularly strong in torsion and efficiently resist the large torsional demands created by the horizontally curved bridge and vehicular centrifugal forces. Some of the advantages of tub girder structural shape that have to lead to increased utilization include improved aesthetic, maintenance and structural benefits. A real time problem from the industry was taken wherein the steel plate girder arrangement has been adopted. The same problem was analysed and designed with steel box girder. This work was carried out as per AASHTO 2010 specification. The analysis of the steel tub girder bridge is done by using professionally available MIDAS Civil software for construction stage analysis, static load analysis and moving load analysis. The curved bridge is more prone to overturning effect. It is necessary to check the bridge superstructure against overturning. The table and graph of Cumulative Reaction of Bearing at Each Construction Stages prove that the tub girder bridge is stable against overturning in all construction stage. The steel tub girder is designed as per AASHTO specification. Wherein all the specification are clearly mentioned. The considered tub section is checked for all the limit state. The steel tub girder design and their performance ratio are within the permissible limit in all limit state such as constructibility limit state, service limit state and strength limit state. The splice connection and intermediate K bracing is designed as per IRC 24:2010. The deck slab is designed as per IRC 112:2019. The shear connector is designed as per IRC 22:2015. The cost analysis of the bridge has been carried out after estimating the superstructure of the steel tub girder and steel plate girder bridge.