The calculation cycle in PFC2D
is a time-stepping algorithm, and the contact force is updated by the force-displacement law.
According to the references given above, the difficulty of screening out a proper set of microparameters can be classified into three categories: (1) The subjectivity of calibrating the microparameters: the calibration process should be more objective and should not depend on the experiments or the experimenter; (2) the hard work of calibrating the microparameters: during the calibration process, the microparameters must be changed by hand for each calibration step, which is time-consuming and tedious; (3) the limited use of the microparameters calibration method: the calibration method should be applied to different kinds of numerical models in both PFC2D
and PFC3D software.
 Itasca Consulting Group, PFC2D
(Particle Flow Code in 2 Dimensions) Fish in PFC2D
, Itasca Consulting Group, Minneapolis, Minn, USA, 2008.
Chi, "The method of particle flow and PFC2D
code," Rock and Soil Mechanics, vol.
All components of SHPB system in experiment were simulated by PFC2D
. In order to reduce the amount of calculation, the CB model was assigned on the transmitted bar, incident bar, and striker.
Yang and Huang  constructed a model for Brazilian disc splitting test using PFC2D
, and then it was used to simulate Brazilian splitting test for jointed rock mass specimens and specimen containing a central straight notch, and the influences of joint angles on tensile strength and failure modes were analyzed.
, there are two kinds of failure modes between particles, that is, the shear failure and the tension failure.
Brief Introduction to PFC2D
. In PFC, rock or rocklike material is presented as a collection of particles with certain thickness.
 combined similar material testing and discrete element numerical method (PFC2D
) to study the peak strength and failure characteristics of rock-like materials with multifissures.
(particle flow code in 2 dimensions)  is the general-purpose code based on discrete element method (DEM) put forward by Cundall , which simulates movement and interaction of granular media, confirming particle's location and velocity in every moment according to the motion equation of translator motion and rotation.
Chu, "Simulation of Rock Grain Breakage Using PFC2D
," Journal of Engineering Geology, vol.
The particle flow code in two dimensions (PFC2D
) program is adopted, and the parallel bond model is introduced to study the crack coalescence modes and the specimen failure process .