task 99===What theoretical frameworks underpin civil engineering practices, shaping infrastructure design, construction methods, and risk assessment? How do principles from fields like structural mechanics, geotechnical engineering, and fluid dynamics inform the development of resilient structures and sustainable urban environments? How do theoretical models such as finite element analysis, computational fluid dynamics, and probabilistic risk assessment enhance our understanding of structural behavior, material properties, and environmental impact? Additionally, how do emerging theories in fields like smart infrastructure, resilient design, and sustainable construction influence the evolution of civil engineering methodologies, addressing challenges posed by climate change, urbanization, and technological advancements?