civil engineering, such as structural mechanics, fluid dynamics, and material science, contribute to the design, construction, and maintenance of infrastructure? Discuss the application of principles like Euler$-$Bernoulli beam theory, Navier$-$Stokes equations, and the mechanics of materials in ensuring the safety, durability, and efficiency of civil projects. How do these theories inform decisions regarding material selection, structural design, and risk management in diverse scenarios, ranging from bridges and buildings to transportation systems and environmental engineering? Additionally, how do advancements in computational methods and modeling techniques enhance the practical implementation of these theories in modern civil engineering practice?"