Candidate:Chi Chiu Lam

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Finite Element Study of Bond-Slip Behaviour of
CFRP and GFRP Laminates on Brick Masonry

• Candidate Chi Chiu Lam
• Supervisors Prof. M. R. Valluzzi
• Dr. E. Garbin
• M. Panizza
• Department of Structural and Transportation
  Engineering
• University of Padova
• Padova, Italy

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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry

• Outline
• Experimental study of bond-slip behaviour of
  FRP-to-
• brick by Panizza et al. (2009)
• Finite element analysis of FRP laminates on brick
  masonry
• Analytical solution proposed by Yuen et al.
  (2004)
• Summary and Conclusion

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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Typical test specimen
50 mm
P/2
P/2
P
120 mm
55 mm
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Test Results
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Finite element analysis
Coarse mesh vs. Fine mesh
CFRP GFRP
Exponential bond-slip vs. Bilinear bond-slip
FRP with concentrated fiber property vs. FRP
with distributed fiber property
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Finite element model
FE program Diana (2008) FRP and Brick element
8 nodes isoparametric plane stress element
(CQ16M) Interface 33 nodes interface element
(CL12I) with bond-slip behaviour
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Finite element material properties
Carbon
Glass
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Coarse mesh vs. Fine mesh
Carbon
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Exponential vs. Bilinear bond-slip curve
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Concentrated fiber vs. Distributed fiber
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
CFRP
GFRP
Exponential
Bilinear
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Analytical solution by Yuan et al. (2004)
where
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Analytical solution by Yuan et al. (2004)
Elastic-softening-debonding stage (B-C-D)
Elastic-softening stage (A-B)
Elastic stage (O-A)
Softening-debonding stage (D-E)
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Analytical solution vs. FE results
CFRP Test average Ecfrp tcfrp 46260 N/mm
GFRP Test average Egfrp tgfrp 18673 N/mm
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Axial Strain of FRP (CFRP specimen)
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Axial Strain of FRP (CFRP specimen)
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Axial Strain of FRP (CFRP specimen)
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Axial Strain of FRP (CFRP specimen)
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Axial Strain of FRP (CFRP specimen)
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Axial Strain of FRP (CFRP specimen)
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Axial Strain of FRP (CFRP specimen)
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Interface shear stress (CFRP specimen)
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Interface shear stress (CFRP specimen)
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Interface shear stress (CFRP specimen)
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Interface shear stress (CFRP specimen)
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Interface shear stress (CFRP specimen)
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Interface shear stress (CFRP specimen)
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Interface shear stress (CFRP specimen)
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Parametric study
Bond length L 80 mm, 120 mm, 160 mm and 200
mm Width ratio of FRP-to-brick bfrp / bbrick
0.042, 0.42 and 1.00
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Effect of bond length
CFRP Test average Ecfrp tcfrp 46260 N/mm
GFRP Test average Egfrp tgfrp 18673 N/mm
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Effect of width ratio of FRP-to-brick
CFRP Test average Ecfrp tcfrp 46260 N/mm
GFRP Test average Egfrp tgfrp 18673 N/mm
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Effect of bond length and width ratio
CFRP Test average Ecfrp tcfrp 46260 N/mm
GFRP Test average Egfrp tgfrp 18673 N/mm
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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Summary and Conclusion

• Finite element analysis of bond-slip behaviour of
  CFRP and GFRP laminates on brick masonry was
  carried out.
• Finite element analysis includes (i) coarse vs.
  fine mesh, (ii) exponential bond-slip vs.
  bilinear bond-slip curve, and (iii) concentrated
  fiber property and distribution property.
• The finite element results, such as the maximum
  load and axial strain of FRP, were compared with
  the test results.
• Comparison of the finite element results to the
  analytical solution proposed by Yuan et al.
  (2004) was made.
• Parametrical study of bond-length and width ratio
  of FRP-to-brick was carried out by using the
  analytical solution.

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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Summary and Conclusion

1. With the average test stiffness of FRP assigned,
   both finite element results and analytical
   results compared well with the test results in
   term of maximum load capacity.
2. Increasing the bond length does not increase the
   maximum load capacity, however, the maximum
   deflection increases with increasing bond length.
   
3. It is shown from the analytical solution that the
   width ratio of FRP to brick does not have
   significant effect to the maximum load capacity
   and deflection, especially for specimen with
   lower stiffness of FRP.

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Finite element study of bond-slip behaviour of
CFRP and GFRP Laminates on Brick Masonry
Grazie !! Thank you !!