NOTE : How do theories serve as foundational frameworks in civil engineering, influencing design, construction, and maintenance practices? Explore the pivotal role of theories in shaping structural analysis, materials science, geotechnical engineering, and fluid mechanics within the field. Discuss the iterative process of theory development, validation through experimentation, and application in real$-$world scenarios. Consider prominent theories like elasticity theory, finite element analysis, and soil mechanics principles, elucidating their impact on infrastructure development and sustainability. Investigate how theoretical frameworks inform decision$-$making processes, risk assessment, and innovative solutions in addressing contemporary challenges such as climate change resilience, urbanization, and infrastructure aging.