"How do changes in soil composition and moisture content impact the stability and load$-$bearing capacity of shallow foundations in civil engineering projects? Consider factors such as soil type, compaction methods, and environmental conditions. Discuss the theoretical frameworks and mathematical models used to analyze these effects, including methods for determining bearing capacity, settlement prediction, and safety factors. Explore how variations in soil properties, such as cohesion and angle of internal friction, influence the behavior of foundations under different loading conditions. Additionally, examine the role of groundwater flow and its interaction with soil mechanics in determining foundation performance. Finally, discuss strategies for mitigating potential risks associated with soil variability and environmental factors, focusing on theoretical principles rather than specific case studies."