Volume 2 - Issue 3, May - June 2026

Transportation infrastructure plays a significant role in the economic and social development of a country. Underpass bridges are essential components of modern transportation systems as they facilitate uninterrupted traffic movement at road intersections, railway crossings, and highways. Due to increasing urbanization and traffic density, RCC box-type underpass bridges are increasingly preferred because of their rigidity, durability, and ability to resist heavy loading conditions. The present study investigates the structural behaviour of RCC box-type underpass bridges subjected to vehicular and seismic loading conditions. Three-dimensional numerical models with span lengths of 5 m, 10 m, and 15 m were developed and analysed using structural analysis software in accordance with IRC and IS 1893:2016 provisions. Static and dynamic analyses were carried out to evaluate displacement, base shear, natural time period, frequency response, acceleration response, and maximum stress. The study also compares the seismic performance of conventional pier-supported bridge systems and RCC box bridge systems. Results indicate that the RCC box bridge configuration exhibits improved rigidity and better seismic resistance with lower displacement response. The 10 m span bridge demonstrated optimum structural performance with minimum displacement and stable dynamic behaviour. The study concludes that moderate-span RCC box-type underpass bridges are structurally efficient and suitable for seismicprone regions.

Mr.Abdul Zareef Abdul Zarrar, Ishant Dahat,"Review on Comparative Study of Dynamic Behavior of Pre-Engineered and Conventional Steel Industrial Structure" International Journal of Advanced Multidisciplinary Research and Educational Development, V2(3): Page(240-246) May-June 2026. ISSN: 3107-6513. www.ijamred.com. Published by Scientific and Academic Research Publishing.