Drainage‐Pressure Relief for Anti‐Uplift Performance in Expansive Clay: A Low‐Carbon Alternative to Conventional Anchors

Extreme weather can cause urban groundwater levels (GWLs) to rise sharply, making anti-uplift performance critical for underground structures. We present a drainage-pressure relief anti-uplift technique (DPRAT) that integrates the Dupuit circular island model, the Thiem equation, and GWL distribution assumptions into an intelligent control system. The system activates automatically when the measured water head exceeds a design threshold, draining groundwater to relieve hydrostatic pressure on buried structures. Tests and simulations in Chengdu's expansive soil areas confirm that anti-uplift failure results primarily from buoyant forces and soil expansion. To ensure adequate safety margins, the target drainage level is calibrated to maintain system inactivity approximately 80% of the time under normal conditions. Four years of field monitoring demonstrate that DPRAT effectively maintains GWLs below the design datum during extreme rainfall events. A 50-year life cycle assessment reveals that DPRAT reduces cradle-to-grave carbon emissions by up to 97.5% compared with conventional uplift anchors, representing a substantial shift from high-energy construction methods to low-carbon alternatives.