ABSTRACT
Bond breakage occurs when either the normal or shear component of the contact force exceeds its corresponding bond strength. The calculation cycle in PFC2D consists of the repeated application of the law of motion to each particle, a force-displacement law to each contact with a constant updating of wall positions. At the start of time step, the set of contacts are updated from the known particle and wall positions. Then the force-displacement law is applied to each contact to update the contact forces based on the relative motion of the two contacting bodies (particle-particle or particle-wall) and the applied contact constitutive model. Next, the law of motion is applied to each particle to update its position and velocity according to the contact forces and/or any body forces.The reader is referred to Itasca Consulting Group (2004) for further information on PFC2D.
