Hypothetical Numerical Evaluation of 10-Year Household Pumping-Induced Settlement Across Representative Soils in Cabanatuan City

This study presents a comparative numerical evaluation of hypothetical household pumping-induced settlement across eleven representative soil profiles in Cabanatuan City, Philippines. Using PLAXIS 3D (2025.1), three household-demand scenarios of 600, 800, and 1000 L/day were represented through proportional phreatic-level reductions over a modeled 10-year period. The scenarios were imposed as relative groundwater-stress conditions only and were not derived from hydrogeologically calibrated field drawdown. Default Mohr-Coulomb material parameters were applied uniformly to isolate comparative soil-response trends. Results showed a consistent increase in modeled settlement with stronger imposed groundwater-stress scenarios across all soil profiles. Brown Sandy Silt exhibited the highest settlement, increasing from 29.50 mm at 600 L/day to 57.18 mm at 1000 L/day, while Hard Brown Clayey Silt showed the lowest response, ranging from 0.6024 mm to 1.093 mm. The findings indicate that silty and sandy soils generally experienced greater relative deformation than denser or more cohesive profiles under the adopted assumptions. The study provides a preliminary comparative framework for geotechnical screening, while emphasizing that the results are not site-specific field predictions.