Multi-objective optimization-driven design of steel-concrete composite bridges for high-speed railway infrastructure

Abstract

High-Speed Railways (HSR) stand as a transformative force in modern transportation, offering swift and efficient alternative to traditional rail systems. Bridges play an essential role in HSR infrastructure. Conventional bridge design would not suffice for the requirements of high-speed railways due to the dynamic effects associated with them and the stringent codal design limits. While conventional bridges primarily utilize prestressed concrete and steel girders, there has been a growing global preference for Steel-Concrete Composite (SCC) girders in recent years. This shift is largely attributed to their exceptional ability to meet the stringent demands posed by high-speed trains. However, designing bridges for HSR is a complex endeavour, requiring a delicate balance between economic efficiency and structural performance. This study introduces an optimization-driven approach to the design of steel-concrete composite HSR bridges, with a particular focus on the twin I-girder and trapezoidal box girder configurations. These bridge designs, specifically tailored for Japanese high-speed trains and compliant with IRC 22: 2015 standards, are optimized using a multi-objective evolutionary algorithm. The present research demonstrates that the trapezoidal box girder offers greater flexibility in meeting structural requirements. On the other hand, the twin I-girder, while exhibiting a similar weight variation to the trapezoidal box girder, shows a more restricted deflection range, indicating a constrained design. This study underscores the importance of selecting an appropriate girder configuration based on specific design objectives, paving the way for more refined, efficient, and effective bridge solutions in high-speed railway systems.