Soil layer parameters.

This study investigates the impact of coupling well-point dewatering with chemical improvement slope stabilization configurations on slope stability. Targeting two slope stabilization types—toe-fixed pier and equidistant borehole configurations—the variation patterns of slope stability coefficients under different dewatering depths, pier parameters, and borehole parameters were analyzed using Geo Studio software. The results demonstrate that dewatering depth significantly enhances slope stability, with an optimal depth of 10 meters effectively reducing pore water pressure at the slip surface and improving stability. For the pier-type configuration, increasing pier height and width within a specific range notably enhances stability, though marginal benefits diminish gradually. In the borehole-type configuration, when the borehole depth is within the range of 2–4 meters, the reinforcement effect on shallow areas is particularly significant, and the slope stability coefficient can be increased by approximately 8.7%. Appropriately reducing the borehole spacing helps to further enhance stability; however, when the spacing is less than 1 meter, the improvement in slope stability is limited. These findings provide a theoretical basis and engineering guidance for optimizing slope stability designs under coastal complex geological conditions.