I cannot get stress and strain of ElasticIsotropic material?

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michaelshu
Posts: 7
Joined: Mon Oct 30, 2006 5:24 am
Location: zhe jiang university

I cannot get stress and strain of ElasticIsotropic material?

Post by michaelshu »

Hi everyone, I encountered a problem about ElasticIsotropic material,that is ,the material cannot output stresses and strain.Whether the material or my script caused the problem?
Thank you in advance!!

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#SI units (m, s, KN, ton)
#              
#               
#         4      
#         ------- 3
#         |     |
#         |     |
#         |     |
#        1-------2   (nodes 1 and 2 fixed)
#         ^     ^
#          <--> input motion: sinusoidal acceleration at base
wipe
#
#some user defined variables
# 
set accMul   2          ;# acceleration multiplier
set massDen  1.0      ;# solid mass density
set fluidDen 0.0        ;# fluid mass density
set massProportionalDamping   0.0 ;
set stiffnessProportionalDamping 0.001 ;
set fangle 31.40         ;#friction angle
set ptangle 26.50        ;#phase transformation angle
set E      90000.0      ;#shear modulus
set poisson 0.40 ;
set G [expr $E/(2*(1+$poisson))] ;
set B [expr $E/(3*(1-2*$poisson))] ;
set press   0.0 ;# isotropic consolidation pressure on quad element(s)
set deltaT   0.010   ;# time step for analysis
set numSteps 2000   ;# Number of analysis steps
set gamma1  0.5
set gamma    0.600    ;# Newmark integration parameter
set period   1      ;# Period of applied sinusoidal load
set pi 3.1415926535     ;
set inclination 0       ;
set unitWeightX [expr  ($massDen-$fluidDen)*9.81*sin($inclination/180.0*$pi)] ;# unit weight in X direction
set unitWeightY [expr -($massDen-$fluidDen)*9.81*cos($inclination/180.0*$pi)] ;# unit weight in Y direction
#############################################################

#create the ModelBuilder
model basic -ndm 2 -ndf 2

 nDMaterial ElasticIsotropic 1 10000 0.4 6.75 ; #: 质量块用线弹性模型模拟  
# nDMaterial J2Plasticity 1 10000 5000 20000 400000 0.5 0.8 
# define the nodes
node 1   0.0D0 0.0D0 
node 2   1.0D0 0.0D0 
node 3   1.0D0 1.0D0 
node 4   0.0D0 1.0D0

# define the element      thick  material      maTag   press    mDensity   gravity 
element quad  1  1 2 3 4  1.0   "PlaneStrain"     1   $press      0.       $unitWeightX  $unitWeightY  

# fix the base
fix 1 1 1 
fix 2 1 1

#tie nodes 3 and 4
# equalDOF 3 4   1 2    
 #:---------------------------------------------
#############################################################
# GRAVITY APPLICATION (elastic behavior)
# create the SOE, ConstraintHandler, Integrator, Algorithm and Numberer
system ProfileSPD
test NormDispIncr 1.D-12 25 0
constraints Transformation
integrator LoadControl 0.1 
algorithm Newton 
numberer RCM

# create the Analysis
analysis Static
recorder Node -file disp21_g.out   -time  -node 3 -dof 1  -dT  0.1 disp
recorder Node -file reaction21_g.out   -time  -node 1 2 -dof 1 2  -dT  0.1 reaction
recorder Element -ele 1 -file strain_g3.out -time material 3 strain -dT 0.1
recorder Element -ele 1 -file stress_g3.out -time material 3 stress -dT 0.1
#analyze 

analyze 2


wipeAnalysis

# create a LoadPattern with a Linear time series
pattern Plain 10 "Linear" {
    load 3 10 0.0    ;#load applied in x direction
}

recorder Element -ele 1 -time -file stress3.out material 3 stress -dT 0.01
recorder Element -ele 1 -time -file strain3.out material 3 strain -dT 0.01


# create the Analysis
constraints Transformation;  # Penalty 1.0e18 1.0e18  ;# 
test NormDispIncr 1.e-12 25 0
algorithm Newton 
numberer RCM
system ProfileSPD
integrator Newmark $gamma  [expr pow($gamma+0.5, 2)/4]  \
	$massProportionalDamping 0.0 $stiffnessProportionalDamping 0.0
analysis VariableTransient 

#analyze 
set startT [clock seconds]
analyze $numSteps $deltaT [expr $deltaT/100] $deltaT 10
set endT [clock seconds]
puts "Execution time: [expr $endT-$startT] seconds."

wipe  #flush ouput stream
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