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[Fu zuoguang <question234879@xxxxxxxxxxxxxxxxxxxxx>]

New question #234879 on Yade:
https://answers.launchpad.net/yade/+question/234879

Dear Bruno Chareyre and all users:
      Thanks for giving me such help last time about the rolling resistence in YADE, I have known from your suggestions that there is nothing different Fundamentally about the rolling resistence algorithm in YADE from that Cundall, Oda & Iwashita mentioned in their papers and in YADE, if the constant relative rolling coefficient is determined, the relative rolling moment may increase linearly with the relative rolling angle's increasing. But as I know from some other papers, this basic method can just only  be considered as a roughness way for concerning the rolling effects for that there is little mechanism validation for providing the standard of relative rolling coefficient determination. It is my work to do that write my own codes in YADE for giving some new models for concerning rolling resistence but not now because my tasks of mechanism validation by experiments are not finished now. Today my questions are just about the structure configure of consolidation in my 2D simulation with clumps.

 The ciumps generation at the beginning of my simulation can be finished sucessfully and the state can be shown as:
(1). http://i.imgur.com/KI0cPLv.png     
(2). http://i.imgur.com/fOoecpf.png

And I have employed these commands for starting the consolidation, which can be described as :

###############################################################################
triax01=TriaxialStressController(
	wall_bottom_id=wallids[2],wall_top_id=wallids[3],
	wall_left_id=wallids[0],wall_right_id=wallids[1],
	wall_back_id=wallids[4],wall_front_id=wallids[5],
	wall_front_activated = False,wall_back_activated = False,
	internalCompaction=False, 
	stressMask=7,
        goal1=10000,
        goal2=10000,
        goal3=10000,
        max_vel=2,
)
#############################################################################
After the consolidation finishing, the structure configure is just like that
http://i.imgur.com/tv24Ymu.png

The length versus width of this specimen is 2:1 but that is much more than that value after consolidation finishing. I can find 
nothing wrong in my script but this state is much different from that of the experiments. Please tells me why and how can I do for getting a correct state of consolidation.

Extension of my points above,  as my understanding of biaxial compression test, the most important purpose of consolidation is to get the target volume of specimen ( in DEM, porosity can be used for defination this target
volume when the initial size of specimen is known ). It is obviously  noticed in accordance with the relationship between 
confining pressure and volume change that the final volume of specimen can be determined by  just only one confining pressure when the material properties are known. So it is very difficult to predetermine the confining pressure for prviding this target volume before the consolidation starting. That is no need for experiments but necessary for DEM. It is just like my codes above, I can not ensure that 10000pa confining pressure can sucessfully give the very volume of this specimen.
Please tell me how to solve my problems. Seeking for your help!  


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