Debonding Limit of the Externally Glued FRP Reinforcements Applied on Clay Brick Substrate: Statistical Assessment of a Design Formula

Abstract:

The present contribution aims to statistically assess a design procedure to estimate the bond resistance of composite fabrics externally glued on clay brick masonry substrates. Based on recent experimental campaigns a database of bond test results between fiber reinforced polymer and clay bricks is collected and an alternative formula is proposed starting from theoretical and experimental evidence. Then, its characteristic value is evaluated following the "Design Assisted by Testing Approach" suggested in the Eurocode 0. The capabilities of the proposed method are statistically evaluated and the advantages with respect to existing formulas are discussed.

• Periodical: Key Engineering Materials (Volume 624)
• Pages: 486-493
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.624.486
• Online since: September 2014
• Authors: Pietro Carrara*, Francesco Freddi
• Keywords: Debonding Resistance, FRP, Masonry Reinforcement, Statistical Assessment

References

[1] Italian ministry for cultural heritage and activities, Guidelines for evaluation and mitigation of seismic risk to cultural heritage. (ISBN: 978-88-492-1269-3), Gangemi ed., Rome, Italy, (2007).

[2] CNR, DT 200-R1/2013 - Guide for the design and construction of externally bonded FRP systems for strengthening existing structures, National Research Council. Rome, Italy, (2013).

[3] ACI Committee 440, 440. 7R-10 - Guide for the design and construction of externally bonded fiber-reinforced polymer systems for strengthening unreinforced masonry structures, American Concrete Institute. Farmington Hills, Michigan: American Concrete Institute, (2010).

DOI: 10.14359/51663675

[4] P. Carrara, D. Ferretti, F. Freddi, Debonding behavior of ancient masonry elements strengthened with CFRP sheets, Compos. Part B Eng., 45, (1), (2013) 800–810.

DOI: 10.1016/j.compositesb.2012.04.029

[5] P. Carrara, D. Ferretti, F. Freddi, and G. Rosati, Shear tests of carbon fiber plates bonded to concrete with control of snap-back, Eng. Fract. Mech., 78, (15), (2011), 2663–2678.

DOI: 10.1016/j.engfracmech.2011.07.003

[6] L. De Lorenzis, B. Miller, A. Nanni, Bond of FRP laminates to concrete, ACI Mater. J., 98, (3), (2001), 256–264.

[7] C. Carloni, K. V. Subramaniam, M. Savoia, and C. Mazzotti, Experimental determination of FRP–concrete cohesive interface properties under fatigue loading, Compos. Struct., 94, (4), (2012), 1288–1296.

DOI: 10.1016/j.compstruct.2011.10.026

[8] P. Carrara, D. Ferretti, A finite-difference model with mixed interface laws for shear tests of FRP plates bonded to concrete, Compos. Part B Eng., 54, (2013), 329–342.

DOI: 10.1016/j.compositesb.2013.05.030

[9] F. Ceroni, A. Garofano, M. Pecce, Modelling of the bond behaviour of tuff elements externally bonded with FRP sheets, Compos. Part B Eng., vol. 59, p.248–259, Mar. (2014).

DOI: 10.1016/j.compositesb.2013.12.007

[10] F. Ceroni, B. Ferracuti, M. Pecce, M. Savoia, Assessment of a bond strength model for FRP reinforcement externally bonded over masonry blocks, Compos. Part B Eng., 61, (2014) 147–161.

DOI: 10.1016/j.compositesb.2014.01.028

[11] P. Carrara, F. Freddi, Statistical assessment of a design formula for the debonding resistance of FRP reinforcements externally glued on masonry units, Compos. Part B Eng., (2014).

DOI: 10.1016/j.compositesb.2014.04.032

[12] E. Grande, M. Imbimbo, E. Sacco, Bond Behavior of Historical Clay Bricks Strengthened with Steel Reinforced Polymers (SRP), Materials 4, (3), (2011), 585-600.

DOI: 10.3390/ma4030585

[13] German Commitee for Reinforced Concrete, DafStb Guideline. On the reinforcement of concrete parts with adhesive bonding (Draft 2012), Deutscher Ausschuss fur Stahlbeton e. V., DAfStb, Berlin-Tiergarten, Germany, (2012).

[14] European Committee for Standardization, BS EN 1990: 2002 - Eurocode 0: Basis of structural design, in: Eurocode 0, Vol. 1, UNI-EN, Bruxelles, Belgium, (2002).

DOI: 10.3403/03202162

[15] K. V. Subramaniam, C. Carloni, L. Nobile, An Understanding of the Width Effect in FRP-Concrete Debonding, Strain, 47, (2), (2011), 127–137.

DOI: 10.1111/j.1475-1305.2008.00481.x

[16] E. Grande, M. Imbimbo, E. Sacco, Bond behaviour of CFRP laminates glued on clay bricks: Experimental and numerical study, Compos Part B -Eng, 42, (2), (2011), 330-340.

DOI: 10.1016/j.compositesb.2010.09.020

[17] M. R. Valluzzi, D. V. Oliveira, A. Caratelli, et al., Round Robin Test for composite-to-brick shear bond characterization, Mater Struct, 45, (12), (2012), 1761-1791.

DOI: 10.1617/s11527-012-9883-5

[18] R. Capozucca, Effects of mortar layers in the delamination of GFRP bonded to historic masonry, Compos Part B - Eng, 44, (1), (2013), 639-649.

DOI: 10.1016/j.compositesb.2012.02.012

[19] M. Panizza, E. Garbin, M. R. Valluzzi, C. Modena, Bond behaviour of CFRP and GFRP laminates on brick masonry, Proc. of the 6th SAHC Conference, (2008).

DOI: 10.1201/9781439828229.ch86

[20] R. Capozucca, Experimental FRP/SRP historic masonry delamination, Compos Struct, 92, (4), (2010), 891-903.

DOI: 10.1016/j.compstruct.2009.09.029

[21] R. Capozucca, Behavior of CFRP sheets bonded to historical masonry, Proc. of the APFIS Conference, Hong Kong, China, (2007), 723-728.

[22] C. Carloni, K. V. Subramaniam, FRP-Masonry Debonding: Numerical and Experimental Study of the Role of Mortar Joints, J Compos Constr, 16, (5), (2012), 581-589.

DOI: 10.1061/(asce)cc.1943-5614.0000282

[23] C. Mazzotti, B. Ferracuti, A. Bellini, Experimental bond tests on masonry panels strengthening by FRP, Proc. of 6th CICE Int. Conference, Rome, Italy, (2012).

DOI: 10.1016/j.compositesb.2015.05.019

[24] C. Faella, G. Camorani, E. Martinelli, S. O. Paciello, F. Perri, Bond behaviour of FRP strips glued on masonry: Experimental investigation and empirical formulation, Constr Build Mater, 31, (2012), 353-363.

DOI: 10.1016/j.conbuildmat.2011.12.100