Fiber Reinforcement Concrete

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orodzarrin
Posts: 16
Joined: Sun Mar 17, 2013 3:26 am
Location: Eastern Mediterranean University

Fiber Reinforcement Concrete

Post by orodzarrin » Sat Mar 15, 2014 10:55 pm

Hello,
I want to model a concrete beam with fiber.The length of the beam is 2 m and has got 2 pint load in each (2/3) 0.6667 m.
I used 2 bars at the bottom of beam its diameter is 20 mm
I think my analysis didn't correct.
1- how can I use fiber in concrete?
2- how can I get Moment-Curvature diagram?
3- how can I get Strain-Stress diagram?
4- I used (eleLoad -ele 1 2 -type beamPoint 500 0.6667 1.3334) commend for imply 2 pint load, is it correct?

I put all my file here.
Please help me.




# Units: kn, m
# Define model builder
# --------------------
model BasicBuilder -ndm 2 -ndf 3
# Define materials for nonlinear columns
# ------------------------------------------
# CONCRETE tag f'c ec0 f'cu ecu
puts "ok 1"
# Core concrete (confined)
uniaxialMaterial Concrete01 1 30000 -0.004 -5.0 -0.014

# Cover concrete (unconfined)
uniaxialMaterial Concrete01 2 30000 -0.004 -5.0 -0.014
puts "ok 2"

# STEEL
# Reinforcing steel
set fy 240000; # Yield stress
set E 200000000; # Young's modulus
# tag fy E0 b

puts "ok 3"

uniaxialMaterial Steel01 3 $fy $E 0.01

puts "ok 4"

# Define cross-section for nonlinear columns
# ------------------------------------------
# set some parameters
set bWidth 0.2
set bDepth 0.1
set cover 0.02
set As 0.000314; # area of no. 20 mm

puts "ok 5"

# some variables derived from the parameters
set by1 [expr $bDepth/2.0]
set bz1 [expr $bWidth/2.0]

puts "ok 6"

section Fiber 1 {
# Create the concrete core fibers
patch rect 1 10 1 [expr $cover-$by1] [expr $cover-$bz1] [expr $cover-$by1] [expr $bz1-$cover] [expr $by1-$cover] [expr $bz1-$cover] [expr $by1-$cover] [expr $cover-$bz1]

# Create the concrete cover fibers (top, bottom, left, right)
patch rect 2 10 1 [expr $by1-$cover] -$bz1 [expr $by1-$cover] $bz1 $by1 $bz1 $by1 -$bz1
patch rect 2 10 1 [expr $cover-$by1] -$bz1 [expr $cover-$by1] [expr $cover-$bz1] [expr $by1-$cover] [expr $cover-$bz1] [expr $by1-$cover] -$bz1
patch rect 2 2 1 -$by1 -$bz1 -$by1 $bz1 [expr $cover-$by1] $bz1 [expr $cover-$by1] -$bz1
patch rect 2 2 1 [expr $cover-$by1] [expr $bz1-$cover] [expr $cover-$by1] $bz1 [expr $by1-$cover] $bz1 [expr $by1-$cover] [expr $bz1-$cover];

puts "ok 7"

# Create the reinforcing fibers (left, middle, right)
layer straight 3 2 $As [expr $cover-$by1] [expr $cover-$bz1] [expr $cover-$by1] [expr $bz1-$cover] # -0.08 -.1 0.08 0.1
}

puts "ok 8"

# Estimate yield curvature
# (Assuming no axial load and only top and bottom steel)
set d [expr $bDepth-$cover] ; # d -- from cover to rebar
set epsy [expr $fy/$E] ; # steel yield strain
set Ky [expr $epsy/(0.7*$d)]

# Print estimate to standard output
puts "Estimated yield curvature: $Ky"

puts "ok 9"


# Define two nodes at (0,0)
node 1 0.0 0.0
node 2 2.0 0.0

puts "ok 10"

# Fix all degrees of freedom except axial and bending at node 2

fix 1 1 1 0
fix 2 1 1 0

puts "ok 11"

geomTransf Linear 2

puts "ok 12"

# Define element
element nonlinearBeamColumn 1 1 2 5 1 2
#element zeroLengthSection 1 1 2 1

puts "ok 13"

# Create recorder
recorder Node -file section.out -time -node 2 -dof 3 disp

puts "ok 14"

# Define constant axial load
pattern Plain 1 Constant {
eleLoad -ele 1 2 -type beamPoint 500 0.6667 1.3334
}

puts "ok 15"
# Define analysis parameters
integrator LoadControl 0.1
system BandGeneral
test NormUnbalance 1.0e-6 25
numberer RCM
constraints Transformation
algorithm Newton
analysis Static

# Do one analysis for constant axial load
analyze 10

puts "ok 16"

orodzarrin
Posts: 16
Joined: Sun Mar 17, 2013 3:26 am
Location: Eastern Mediterranean University

Re: Fiber Reinforcement Concrete

Post by orodzarrin » Sun Mar 23, 2014 9:14 am

Please help me.

orodzarrin
Posts: 16
Joined: Sun Mar 17, 2013 3:26 am
Location: Eastern Mediterranean University

Re: Fiber Reinforcement Concrete

Post by orodzarrin » Sun Mar 30, 2014 9:35 pm

There is n't anybody to help me?

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