The intrinsic cohesion of granular materials

An exact solution to the rigid-plastic equations is presented, which contai ns inertial terms, together with a nonzero (intrinsic) cohesion, S-0. Match ing the mass flow from this exact solution to that predicted in Beverloo-ty pe equations, identifies S-0 as equal to about rho gd/2, where d is a chara cteristic particle diameter. This cohesion suggests the presence of dead re gions about orifice boundaries, and of arching in narrow orifices. The solu tion is only defined beneath an elliptical arch above the outlet of the hop per orifice. (C) 1999 Elsevier Science S.A. All rights reserved.