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[Zhipeng Huang <question686871@xxxxxxxxxxxxxxxxxxxxx>]

New question #686871 on Yade:
https://answers.launchpad.net/yade/+question/686871

Hello：）
I found an example code of triaxial test. It uses 'aabbwalls’ and 'triaxialstresscontroller' to apply confining pressure.After applying confining pressure, I want to add an angular velocity of 0.1m/s of the top wall to simulate the situation of rotation shear.But the wall didn't rotate.here is the code.Can anyone help me ,thank you!

from yade import pack
############################################
###   DEFINING VARIABLES AND MATERIALS   ###
############################################

# The following 5 lines will be used later for batch execution
nRead=readParamsFromTable(
	num_spheres=1000,# number of spheres
	compFricDegree = 30, # contact friction during the confining phase
	key='_triax_base_', # put you simulation's name here
	unknownOk=True
)
from yade.params import table

num_spheres=table.num_spheres# number of spheres
key=table.key
targetPorosity = 0.43 #the porosity we want for the packing
compFricDegree = table.compFricDegree # initial contact friction during the confining phase (will be decreased during the REFD compaction process)
finalFricDegree = 30 # contact friction during the deviatoric loading
rate=-0.02 # loading rate (strain rate)
damp=0.2 # damping coefficient
stabilityThreshold=0.01 # we test unbalancedForce against this value in different loops (see below)
young=5e6 # contact stiffness
mn,mx=Vector3(0,0,0),Vector3(1,1,1) # corners of the initial packing


## create materials for spheres and plates
O.materials.append(FrictMat(young=young,poisson=0.5,frictionAngle=radians(compFricDegree),density=2600,label='spheres'))
O.materials.append(FrictMat(young=young,poisson=0.5,frictionAngle=0,density=0,label='walls'))

## create walls around the packing
walls=aabbWalls([mn,mx],thickness=0,material='walls')
wallIds=O.bodies.append(walls)

## use a SpherePack object to generate a random loose particles packing
sp=pack.SpherePack()


clumps=False #turn this true for the same example with clumps
if clumps:
 ## approximate mean rad of the futur dense packing for latter use
 volume = (mx[0]-mn[0])*(mx[1]-mn[1])*(mx[2]-mn[2])
 mean_rad = pow(0.09*volume/num_spheres,0.3333)
 ## define a unique clump type (we could have many, see clumpCloud documentation)
 c1=pack.SpherePack([((-0.2*mean_rad,0,0),0.5*mean_rad),((0.2*mean_rad,0,0),0.5*mean_rad)])
 ## generate positions and input them in the simulation
 sp.makeClumpCloud(mn,mx,[c1],periodic=False)
 sp.toSimulation(material='spheres')
 O.bodies.updateClumpProperties()#get more accurate clump masses/volumes/inertia
else:
 sp.makeCloud(mn,mx,-1,0.3333,num_spheres,False, 0.95,seed=1) #"seed" make the "random" generation always the same
 O.bodies.append([sphere(center,rad,material='spheres') for center,rad in sp])
 #or alternatively (higher level function doing exactly the same):
 #sp.toSimulation(material='spheres')

############################
###   DEFINING ENGINES   ###
############################

triax=TriaxialStressController(
	## TriaxialStressController will be used to control stress and strain. It controls particles size and plates positions.
	## this control of boundary conditions was used for instance in http://dx.doi.org/10.1016/j.ijengsci.2008.07.002
	maxMultiplier=1.+2e4/young, # spheres growing factor (fast growth)
	finalMaxMultiplier=1.+2e3/young, # spheres growing factor (slow growth)
	thickness = 0,
	## switch stress/strain control using a bitmask. What is a bitmask, huh?!
	## Say x=1 if stess is controlled on x, else x=0. Same for for y and z, which are 1 or 0.
	## Then an integer uniquely defining the combination of all these tests is: mask = x*1 + y*2 + z*4
	## to put it differently, the mask is the integer whose binary representation is xyz, i.e.
	## "100" (1) means "x", "110" (3) means "x and y", "111" (7) means "x and y and z", etc.
	stressMask = 7,
	internalCompaction=True, # If true the confining pressure is generated by growing particles
)

newton=NewtonIntegrator(damping=damp)

O.engines=[
	ForceResetter(),
	InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Box_Aabb()]),
	InteractionLoop(
		[Ig2_Sphere_Sphere_ScGeom(),Ig2_Box_Sphere_ScGeom()],
		[Ip2_FrictMat_FrictMat_FrictPhys()],
		[Law2_ScGeom_FrictPhys_CundallStrack()]
	),
	## We will use the global stiffness of each body to determine an optimal timestep (see https://yade-dem.org/w/images/1/1b/Chareyre&Villard2005_licensed.pdf)
	GlobalStiffnessTimeStepper(active=1,timeStepUpdateInterval=100,timestepSafetyCoefficient=0.8),
	triax,
	TriaxialStateRecorder(iterPeriod=100,file='WallStresses'+table.key),
	newton
]

#Display spheres with 2 colors for seeing rotations better
Gl1_Sphere.stripes=0
if nRead==0: yade.qt.Controller(), yade.qt.View()

## UNCOMMENT THE FOLLOWING SECTIONS ONE BY ONE
## DEPENDING ON YOUR EDITOR, IT COULD BE DONE
## BY SELECTING THE CODE BLOCKS BETWEEN THE SUBTITLES
## AND PRESSING CTRL+SHIFT+D

#######################################
###   APPLYING CONFINING PRESSURE   ###
#######################################

#the value of (isotropic) confining stress defines the target stress to be applied in all three directions
triax.goal1=triax.goal2=triax.goal3=-10000

#######################################
###   APPLYING angular velocity   ###
#######################################
angvel=O.bodies[0].state.angVel
angvel[0]=0.1



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