Composite materials have gained considerable attention in bridge engineering due to their perfect corrosion resistance, strength-toweight ratio, and durability. However, the relatively high cost of composite materials necessitates the development of structures with optimized material distribution to minimize both cost and weight.  In structural engineering, topology optimization is a complex tool. It serves to optimize material distribution within a prescribed design space. Its primary objective is to achieve the highest attainable material performance while adhering to a set of constraints. We employ a Tailor Processing Technique (TPT) to transform these optimization results into
feasible designs, addressing this challenge. Utilizing this technique, a unit-model bridge deck is meticulously designed through topology optimization. Subsequently, composite materials are incorporated, and their performance is evaluated. The main purpose of this work is to perform topology optimization to design the unit model deck as light as possible while keeping important parameters like load-bearing capacity, stiffness, and constraint. The refinement process achieves this by using composite materials instead of concrete. A comparative analysis is conducted between a composite bridge deck designed using TPT and a traditional reinforced concrete unit model bridge deck. This comparison highlights the significant advantages offered by this innovative design approach, notably its exceptional stiffness,enhanced corrosion
resistance,strength-to-weight ratio, and superior fatigue resistance. A TPT-designed deck achieves a remarkable weight reduction of 88% compared to the traditional deck and 13% compared to published GFRP decks. Additionally, a novel deck cross-section is introduced.