TY - GEN
T1 - Modifications for the smooth joint contact model in the particle flow code
AU - Mehranpour, M. H.
AU - Kulatilake, P. H.S.W.
N1 - Funding Information:
The research was funded by the National Institute for Occupational Safety, and Health (NIOSH) of the Centers for Disease Control, and Prevention (Contract No. 200-2011-39886).
Publisher Copyright:
© 2017 ARMA, American Rock Mechanics Association.
PY - 2017
Y1 - 2017
N2 - This paper deals with the following two shortcomings of the smooth joint contact model (SJCM) used in the particle flow code (PFC): (a) Use of a constant value for joint normal stiffness instead of allowing actual non-linear behavior between the joint normal deformation and joint normal stress; (b) The so called "interlocking problem". The first one is solved by imposing a linear relation between the joint normal stiffness and the normal contact stress in a new modified smooth-joint contact model (MSJCM). A good agreement obtained between the results from the experimental tests and the numerical modeling of the compression joint normal test, shows the accuracy of this new model. The second shortcoming occurs due to a lack of an updating procedure in the PFC software related to the contact conditions of the particles that lie around the intended joint plane during high shear displacements. This problem increases the shear strength of the joint when the shear displacement of the joint exceeds a specific value and creates unwanted fractures around the intended joint plane. To solve this problem a new approach termed joint side checking (JSC) is proposed. Numerical modeling of the direct shear test shows JSC can solve the interlocking problem and proves to be more consistent with the theory compared to the regular approach.
AB - This paper deals with the following two shortcomings of the smooth joint contact model (SJCM) used in the particle flow code (PFC): (a) Use of a constant value for joint normal stiffness instead of allowing actual non-linear behavior between the joint normal deformation and joint normal stress; (b) The so called "interlocking problem". The first one is solved by imposing a linear relation between the joint normal stiffness and the normal contact stress in a new modified smooth-joint contact model (MSJCM). A good agreement obtained between the results from the experimental tests and the numerical modeling of the compression joint normal test, shows the accuracy of this new model. The second shortcoming occurs due to a lack of an updating procedure in the PFC software related to the contact conditions of the particles that lie around the intended joint plane during high shear displacements. This problem increases the shear strength of the joint when the shear displacement of the joint exceeds a specific value and creates unwanted fractures around the intended joint plane. To solve this problem a new approach termed joint side checking (JSC) is proposed. Numerical modeling of the direct shear test shows JSC can solve the interlocking problem and proves to be more consistent with the theory compared to the regular approach.
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M3 - Conference contribution
AN - SCOPUS:85047770611
T3 - 51st US Rock Mechanics / Geomechanics Symposium 2017
SP - 3007
EP - 3013
BT - 51st US Rock Mechanics / Geomechanics Symposium 2017
PB - American Rock Mechanics Association (ARMA)
T2 - 51st US Rock Mechanics / Geomechanics Symposium 2017
Y2 - 25 June 2017 through 28 June 2017
ER -