GEOTECHNICAL AND HYDRAULIC SIMULATION MODELS FOR SLOPE STABILITY AND DRAINAGE OPTIMIZATION IN RAIL INFRASTRUCTURE PROJECTS

Abstract

Rail earthworks often experience rainfall-driven pore-pressure increases and drainage bottlenecks that produce recurring wet spots, deformation, and higher instability risk, yet quantitative evidence linking simulation effectiveness to improved drainage and slope outcomes remains limited. This study tested a coupled geo-hydraulic performance model to quantify predictive relationships among Geotechnical Simulation Effectiveness (GSE), Hydraulic–Hydrologic Simulation Effectiveness (HSE), Drainage Optimization Outcomes (DOO), and Slope Stability Performance (SSP) in an enterprise rail-corridor case context. Using a quantitative cross-sectional, case-based design, data were collected through a structured 5-point Likert questionnaire from N = 210 rail-infrastructure professionals representing geotechnical, hydraulic/drainage, construction, and maintenance functions with direct exposure to simulation-informed decisions and field results. Composite variables were computed as item-mean indices, and analysis included descriptive statistics, reliability testing, Pearson correlation, and staged regression aligned to hypotheses, including an optional mediation path (HSE → DOO → SSP). Measurement reliability was strong (α = 0.87–0.90). Mean scores were above the midpoint (GSE 3.84 ± 0.58; HSE 3.76 ± 0.62; DOO 3.69 ± 0.60; SSP 3.73 ± 0.57). Correlations supported the model (GSE–SSP r = 0.61; HSE–DOO r = 0.67; DOO–SSP r = 0.55; all p < .001). The combined regression predicting SSP was significant (F(3,206) = 62.84, p < .001; R² = 0.48), with unique effects for GSE (β = 0.31), DOO (β = 0.24), and HSE (β = 0.16, p = 0.012). Reduced HSE influence after adding DOO suggested partial mediation, indicating hydraulic modelling improves stability partly via drainage.