Prestressed Concrete Box Girder Bridge with Corrugated Steel Webs

Abstract

The history of the development of the bridges is closely associated with the history of human civilization. The bridge engineers has always a desire to build new type of bridges, either new in concept or new in technique of construction. The hybrid prestressed concrete bridges with corrugated steel webs was originally developed in France in the 1980’s and later introduced to Japan in the 1990’s. In this types of bridge the concrete webs are replaced with trapezoidally corrugated steel plates to reduce the dead load of the structure. It also helps in improving the prestress efficiency, reducing the construction work, and cost. Moreover corrugated webs avoids stiffeners usually needed in flat plate webs. The project delat with analysis and deisgn of 2 span continuous prestressed concrete box-girder bridges with corrugated steel webs. Analysis of the conventional bridge and bridge with corrugated webs subjected to dead load, superimposed load and moving load (Class AA tracked, class AA wheeled and class A train of vehicle as per IRC loading) are carried out using Staad Pro Software. Design of 2 span continuous prestressed concrete bridge with rectangular box girder is carried out as per IRC 18:2000 while prestressed concrete bridge with trapezoidally corrugated steel webs has been carried out as per IRC 22:2008. It is necessary to design the webs without buckling at the ultimate limit state. Stresses has been calculated for these three buckling modes local, global, interactive shear buckling. Lateral torsional buckling capacity has been also calculated. Cost comparison among the conventional PC box girder bridge with corrugated steel webs box Girder Bridge are also worked out. Unit weight comparison between the conventional PC box girder bridge with corrugated steel webs box Girder Bridge is carried out. Economy mainly depends on various factors like span and superstructure cross sectional dimensions. The present study includes parametric study on PC box girder with corrugated steel webs for two lane Road Bridge by changing span to depth ratio and changing depth of web to depth of corrugation in such a way that it become most economical box girder. Parametric study was done for calculation of most economical L/D ratio and hw/d ratio for 40m, 45m and 50m.For this all costing was done with quantity analysis and rate analysis as per current market rates.