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[Swapnil <question659526@xxxxxxxxxxxxxxxxxxxxx>]

Question #659526 on Yade changed:
https://answers.launchpad.net/yade/+question/659526

Swapnil posted a new comment:
Sorry, for using "we" before. I did not intend it to use it seriously though.
But your response was perfect Jerome. I included the deviatoric component of the script into the current code.

Earlier, I was trying it without the deviatoric part not  noticing its
significance to the initial set-up here (even more than that in a real
lab experiment  ;)). Now I can understand the functioning of the code
better.

the full script is as follows.  another question at this stage:  What
command to use in order to confine the spheres within the parallelopiped
container. The spheres are moving out during the loading with my script.
I am looking for a solution in the documentation while you answer ;)

from yade import pack,plot,qt
import math

num_spheres=10000   # number of spheres
young=3e10
compFricDegree = 30 # initial contact friction during the confining phase
finalFricDegree = 30 # contact friction during the deviatoric loading
mn,mx=Vector3(0,0,0),Vector3(0.1,0.1,0.1) # corners of the initial packing

O.materials.append(FrictMat(young=young,poisson=0.3,frictionAngle=radians(compFricDegree),density=2600,label='spheres'))
O.materials.append(FrictMat(young=young,poisson=0.5,frictionAngle=0,density=0,label='walls'))
walls=aabbWalls([mn,mx],thickness=0,material='walls')
wallIds=O.bodies.append(walls)

sp=pack.SpherePack()
sp.makeCloud(mn,mx,-1,0.5,num_spheres,False,0.40,seed=1) #"seed" make the "random" generation always the same
sp.toSimulation(material='spheres')


newton=NewtonIntegrator(damping=0.3)

O.engines=[
 ForceResetter(),
 InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Box_Aabb(),Bo1_Wall_Aabb()]),
 InteractionLoop(
  [Ig2_Sphere_Sphere_ScGeom(),Ig2_Box_Sphere_ScGeom()],
  [Ip2_FrictMat_FrictMat_FrictPhys()],
  [Law2_ScGeom_FrictPhys_CundallStrack()],label='iloop'
 ),
 TriaxialStressController(label='triax',
 maxMultiplier=1.+2e4/young, # spheres growing factor (fast growth)
 finalMaxMultiplier=1.+2e3/young, # spheres growing factor (slow growth)
 thickness = 0,
 stressMask =7,
 max_vel = 0.005,
 internalCompaction=True, # If true the confining pressure is generated by growing particles
),GlobalStiffnessTimeStepper(active=1,timeStepUpdateInterval=50,timestepSafetyCoefficient=0.8),PyRunner(iterPeriod=100,command='addPlotData()'),
 newton
]

#O.dt=0.005*PWaveTimeStep()
#strain_rate=-0.05
triax.goal1=triax.goal2=triax.goal3=-5000

#Deviatoric loading
##We move to deviatoric loading, let us turn internal compaction off to keep particles sizes constant
triax.internalCompaction=False

## Change contact friction (remember that decreasing it would generate instantaneous instabilities)
setContactFriction(radians(finalFricDegree))

##set stress control on y and z, we will impose strain rate on x
triax.stressMask = 6
##now goal2 is the target strain rate
triax.goal2=-0.01
## we define the lateral stresses during the test, here the same 10kPa as for the initial confinement.
triax.goal1=-10000
triax.goal3=-10000
##Save temporary state in live memory. This state will be reloaded from the interface with the "reload" button.
O.saveTmp()


def addPlotData():
  plot.addData(i=O.iter,Sz=-triax.stress(triax.wall_right_id)[0], Dz=-triax.strain[0])
  
plot.plots= {'Dz':('Sz')}
plot.plot()

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