Dynamics of large and rapid landslides with long travel distances under dense gas expanding power

This paper mechanistically investigates the dynamics of large and rapid landslides with long travel distance. In addition to many existing theories for friction reduction, the paper puts forward a new cause and mechanism of dense natural gas expanding and its governing equations and numerical results. The dense gas can have a huge amount of time-dependent expansion energy and pressure to deform, suddenly rupture and push the above rock and soil mass. Under gravity, the expanding dense gas and the broken rock and soil debris can rapidly flow, fly, and/or slide over and down the slope. The continued gas expanding and its almost zero shear strength beneath and within the debris solids carry them to powerfully move and travel to much longer distance.