Clogging is a major geohazards risk in mechanized tunnelling through cohesive soils. Clay clogging results from the high adhesion between the clay and metal. Based on the water film theory and Reynolds fluid equation. the interfacial adhesion between metal and soil is simplified in this study as viscous hydrodynamic behavior between planes. https://www.spidertattooz.com/Chill-Pill-Zirconium/