Extracting shear force by Fix store/force

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1

Hi everyone,

In order to monitor the load transfer between two CNT, I extracted the shear force during the pull-out process by command fix store/force. The inner CNT is fixed and the outer one is pull out by command fix move. Part of input file is given as follows:

velocity inner set 0 0 0 units box

velocity outer set 0 0 0 units box

delete_bonds all multi

fix 4 inner store/force

fix 5 outer store/force

compute f1 inner reduce sum f_4[1]

compute f2 outer reduce sum f_5[1]

variable F3 equal c_f1

variable F4 equal c_f2

fix 1 inner move linear 0 0 2 units box

fix 2 outer setforce 0.0 0.0 0.0

fix 3 outer nve

However, the calculated shear force is different from that given in other references. I want to know is it right to utilize fix move for pull-out test and fix store/force for calculating shear force?

Kind regards,

MC.

2

If you read the doc page for fix store/force it simply stores the
pair style forces before additional constraints are added. Whether
that is the correct force you want is up to you. I suggest you
build a static geometry where there is a shear force, dump the
forces to a file, sum them, and check whether everything is consistent.

Steve