Geotechnical Engineering and Soil Mechanics: Delve into the theoretical framework of geotechnical engineering and soil mechanics, addressing concepts such as soil formation, classification, and behavior under loading. Explore fundamental soil properties like grain size distribution, porosity, and shear strength, and discuss how these properties influence the stability and deformation of soil masses. Investigate theoretical models for analyzing slope stability, bearing capacity, and settlement of foundations, considering factors such as soil$-$structure interaction, groundwater effects, and geotechnical hazards. Furthermore, examine theoretical approaches to soil improvement techniques such as compaction, stabilization, and reinforcement, and their applications in geotechnical engineering practice.