Geotechnically Informed Monitoring-Data Fusion and Gradient-Boosted Regression for Instrumented Driven Piles

Long-term monitoring can test whether pile-design assumptions remain appropriate as consolidation and soil-pile load transfer develop after construction. This study combines records from three Ontario transportation projects: Ramsayville, Locha Creek, and Nash Road. The database contains 53,218 weekly movement records, 152 sensor channels, 1714 axial-load profiles, and ten instrumented piles. Baseline-referenced axial-force changes were interpreted together with pore pressure, ground and pile movement, soil-test results, pile geometry, load tests, and construction history. Conventional total-stress and effective-stress calculations were retained as engineering baselines, while gradient-boosted models were used to examine nonlinear residuals and the relative influence of measured inputs. A bounded cross-site mobilization relation achieved an in-sample RMSE of 100.0 kN ($R^2=0.71$) and a leave-one-site-out RMSE of 110.2 kN. In a separate Ramsayville daily forecasting analysis, a seven-day moving average outperformed LightGBM and CatBoost, showing that greater model complexity did not improve short-term prediction. The confirmed cost of the full Ramsayville research monitoring program is CAD 678,700: CAD 267,200 for the test-pile program and CAD 411,500 for the production-pile program. A reduced regional seed-site program is estimated at CAD 225,700. At Locha Creek, the project reference exceeded the conditional 95% screening value by 7.9%, equivalent in cost to 2.30 m of installed pile length, or about CAD 919 per representative 29 m pile at CAD 400/m. The corrected break-even scale is approximately 246 similar piles. No screened reduction was supported at Ramsayville or Nash Road. The results define a monitoring-to-design framework that can identify both conservative and unconservative assumptions. Any design modification must still satisfy the governing geotechnical, structural, serviceability, drivability, group, founding, durability, and reliability requirements.