STRUCTURAL ANALYSIS AND DESIGN OF A PSC FLAT SLAB BRIDGE DECK FOR URBAN OVERPASSES

Abstract

As modern urban landscapes become increasingly congested, the demand for infrastructure that balances structural integrity with geometric efficiency has never been higher. This thesis explores the structural analysis and design of a Prestressed Concrete (PSC) flat slab bridge deck, a specialized system that supports the concrete deck directly on columns or piers without the aid of intermediate longitudinal or transverse beams. The research highlights the transition toward flat slab bridges driven by several critical engineering factors. By eliminating bulky girders, the construction depth is minimized, which subsequently reduces the required height of approach embankments and overall project costs. Furthermore, the use of pre-stressing technology allows for thinner sections and longer spans, effectively reducing the dead load of the structure while maintaining structural efficiency. From a logistical standpoint, the flat soffit simplifies the formwork and shuttering process, enabling faster construction cycles a necessity for minimizing The core of this study focuses on the complex two-way slab action inherent in these structures, where loads are transferred in multiple directions to support points. This necessitates a sophisticated application of plate theory and an in-depth understanding of shear distribution. This research assesses the structural reliability and serviceability of a bridge under various load conditions. The analysis recorded a maximum deflection of 24.207 mm, satisfying the IRC:112 limit of 25 mm. Findings indicate that utilizing panel drops optimizes load transfer, significantly reducing stress compared to standard flat slabs. While mid-span vehicle positioning governs deflection, support zones dictate shear and negative moment design. High reinforcement needs are met through a 1.07% ratio using 20 mm bundled bars. Finite element modelling confirms the design is safe, stiff, and compliant with all engineering standards