Analysis of Test Results - Memorial University of …hmarzouk/Slab test.pdf · Analysis of Test...
Transcript of Analysis of Test Results - Memorial University of …hmarzouk/Slab test.pdf · Analysis of Test...
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Analysis of Test Results
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What we’ll have to do:
• Load-Deflection curve.
• Load Vs Strain curve for steel and concrete
• Find yield load (εs = 0.002) for flexural rebar and strain at failure load for concrete and rebar.
• First yield load for flexural reinforcement.
• Ductility of the slab.
• Energy absorption.
• Deflection profile.
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• Calculate flexural strength and Punching shear capacity of the slab.
• Compare test result with predicted result.
• Show a photograph depicting the crack pattern at failure.
• Make comment on the mode of failure of the slab.
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Tension Reinforcement and Strain gauges arrangement
T1(1050,845);T2(1260,1020);T3(1460,845);T4(1590,1020);T5(810,1080)
T1
T2
T3
T4T5
1900
1900
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Compression Reinforcement and Strain gauges arrangement
C9
C8
C7C6
C6(820,770); C7(1090,820); C8(820,580); C9(820,400)
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Concrete Strain gauge locations
5
4
3
2
1
30, 70, 100, 100
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Load-Deflection curve
Load vs Central Deflection
0.0
50.0
100.0
150.0
200.0
250.0
-40.0 -30.0 -20.0 -10.0 0.0 10.0 20.0 30.0 40.0
Deflection (mm)
Load
(KN
)
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Load-Deflection curve
Load vs Central Deflection
0.0
50.0
100.0
150.0
200.0
250.0
0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0
Deflection (mm)
Load
(NK
)
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Load-Deflection curveLoad vs Central deflection
0.0
50.0
100.0
150.0
200.0
250.0
0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0
Deflection (mm)
Load
(KN
)
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Load vs Strain curve for steel and concreteLoad vs Strain in Steel (T2)
0.0
50.0
100.0
150.0
200.0
250.0
-500 0 500 1000 1500 2000 2500
Micro-Strain
Load
(KN
)
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Load vs Strain curve for steel and concrete
Load vs Strain in steel (T2)
0.0
50.0
100.0
150.0
200.0
250.0
-500 0 500 1000 1500 2000 2500
Micro-Strain
Load
(KN
)
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Load vs Strain curve for steel and concrete
Load vs Strain in steer (T2)
0.0
50.0
100.0
150.0
200.0
250.0
-500 0 500 1000 1500 2000 2500
Mocro-Strain
Load
(KN
)
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Load vs Strain curve for steel and concreteLoad vs Strain in Concrete(3)
0.0
50.0
100.0
150.0
200.0
250.0
-2500 -2000 -1500 -1000 -500 0
Mocro-strain
Load
(KN
)
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Load vs Strain curve for steel and concrete
Load vs Strain in Concrete (3)
0.0
50.0
100.0
150.0
200.0
250.0
-2500 -2000 -1500 -1000 -500 0
Micro-Strain
Load
(KN
)
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Load vs Strain curve for steel and concreteLoad vs Strain in Concrete (3)
0.0
50.0
100.0
150.0
200.0
250.0
-2500 -2000 -1500 -1000 -500 0
Micro-Strain
Load
(KN
)
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Steel Strain Distribution
100 KN
150 KN
200 KN
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Concrete Strain Distribution
50 KN
100 KN
150 KN
200 KN
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• Find yield load (εs = 0.002) for flexural rebar and strain at failure load for concrete and rebar.
• First yield load for flexural reinforcement.
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Ductility and Energy Absorption of the Slab
Ductility = Ratio of the deflection at 25% of maximum load (after reaching the maximum load) to the deflection at the first yielding of flexural reinforcement.
Energy Absorption = Area under the load deflection curve up to 25 % maximum load (after reaching the maximum load)
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Ductility and Energy Absorption of the Slab
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Deflection Profile
1 division = 0.01 mm
1 cycle = 1 mm
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Calculation of Flexural strength
( )( )cyyo
oflex
ffdfMca
sK
KMP
'2 /59.01
172.08
ρρ −=
⎟⎠⎞
⎜⎝⎛ −−
=
=
tesrcylinderfromfmmd
MPafor
c
y
__120
4000.15.0
' =
=
==ρ
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Calculation of Punching Shear Capacity
( )dccbdbfV
o
occu
224.0
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'
++=
= λφ
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Compare Test result with Predicted result
Pflex Pv Ppred. Ptest Ptest/Ppred.
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Show a photograph depicting the crack pattern at failure and Make
comment on the mode of failure of the slab
flex
test
PP
=φ If φ ≥ 1 , Flexural failure
If φ < 1 , Punching Shear failure→
→ From crack pattern
Make comment on mode of failure