Pore Pressure Sensor-Based Early Warning System for Slope Stability

Quick clay landslides are frequent events that can cause catastrophic consequences. They can result in loss of human life, economic losses, and environmental damage. These landslides exhibit retrogressive characteristics and high mobility, primarily triggered by human interventions that affect in-situ pore pressure or slope geometry. In Norway, a significant portion of the population lives in areas at risk of quick clay landslides, necessitating the development and implementation of effective hazard assessment and management strategies. To address this need, this study proposes a framework for an early warning system by monitoring the increase in pore pressure due to human intervention. The proposed framework is implemented on two slopes with poor stability conditions. The slopes were examined using pore pressure sensors installed at various locations and depths. Slope stability analyses were conducted using a limit-equilibrium-based model. The DSHANSEP method was employed to correlate increases in pore pressure with reductions in undrained shear strength, within the context of the Mohr-Coulomb failure criteria. A four-stage warning level identification is proposed based on the required safety level by Norwegian standards and guidelines. The proposed methodology for pore pressure sensor-based early warning system is found a reasonable approach for mitigating the risks associated with pore pressure increase on quick clay slopes.