Humidity effects of two-dimensional granular column collapse

The characteristics of wet granular materials is of great research value; however, current research lacks a unified theoretical framework to systematically explain the influence of cohesive forces on the macroscopic failure behavior of granular materials. In contrast to dry granular materials, the mechanical behavior and kinematic characteristics of wet granular materials are more intricate due to the presence of interstitial fluids. The present study investigates the collapse of a wet granular column with different moisture content. The collapse mode, the duration of exercise, the shape of the deposit, the particle diffusion distance, and the height of the deposit after the collapse are analyzed. Scaling law analyses are also performed to characterize the effects of water content, particle size, and initial aspect ratio on the collapse of the granular column. Power law relationships were derived for diffusion distance and deposition height vs initial aspect ratio, and a new scaling law was developed to predict the collapse behavior of wet granular columns in the funicular state.