Exploring foundational theories in civil engineering involves scrutinizing principles like structural mechanics, materials science, and fluid dynamics. These theories underpin the design and construction of infrastructure, ensuring safety, durability, and functionality. From Euler's buckling theory to Navier$-$Stokes equations, each contributes to understanding the behavior of structures under various loads and environmental conditions. Such theoretical frameworks guide engineers in optimizing designs and mitigating risks, essential for the advancement and sustainability of civil engineering practices.