post-tensioned simply supported prestressed concrete (PC) I-girder bridges are
widely used bridge system for short to medium span (20m to 50m) highway bridges due to its moderate self-weight, structural efficiency, ease of fabrication, low maintenance etc.

In order to compete with steel bridge systems, the design of PC I-girder Bridge system must lead to the most economical use of materials. In this paper, the cost optimization approach of a post-tensioned PC I-girder bridge system is presented. The objective is to minimize the total cost in the design process of the bridge system considering the cost of materials, fabrication and installation. For a particular girder span and bridge width, the design variables considered for the cost minimization of the bridge system, are girder spacing, various cross-sectional dimensions of the girder, number of strands per tendon, number of tendons, tendons configuration, slab thickness and ordinary reinforcement for deck slab and girder.