This study investigates the efficacy of cemented stone columns and encased cemented stone columns for enhancing settlement and bearing capacity in soft soils through numerical simulation and experimental validation. Utilizing PLAXIS 3D software, the Mohr–Coulomb model was employed to simulate the behavior of stone column materials and soft clay soils. Experimental work focused on columns constructed with various proportions of demolition aggregate and natural aggregate: 100% Natural, 25% Demolition +75% Natural, 50% Demolition +50% Natural, 75% Demolition +25% Natural, and 100% Demolition aggregate. The study further explored the effects of bamboo encasement and varying length-to-diameter (L/D) ratios (4, 6, and 8) on performance. Results indicated that the optimal load-carrying capacity was achieved with the 75% Demolition aggregate and 25% Natural aggregate combination, which demonstrated approximately 75–80% of the load-bearing capacity, compared to columns with 100% Natural aggregate. Comparison between experimental and numerical results revealed minor deviations. Notably, single stone columns reduced settlement by 1% to 5%, while groups of stone columns reduced settlement by up to 46% in soft soil conditions. The findings underscore the effectiveness of using cemented stone columns and bamboo encasements in improving the load-bearing capacity and reducing settlement in soft soils, providing valuable insights for practical applications in geotechnical engineering.