Soil improvement is the systematic application of engineering principles and techniques to modify the physical, chemical, or biological properties of a soil mass, enhancing its performance and suitability for specific engineering, agricultural, or environmental purposes. As an academic concept and research field, it investigates the characterization of problematic soils, the mechanisms underlying property modification, and the efficacy of various treatment methodologies, holding significance for sustainable infrastructure development, optimized agricultural productivity, and environmental remediation by transforming unsuitable ground conditions into viable substrates.