An Investigation on In-situ Strength and Bonding Strength of Polymer Modified Concretes (PMC) as Repair Overlays on Conventional Concrete Substrate

Document Type : Regular Paper

Authors

1 Associate Professor, Faculty of Engineering, University of Guilan, Rasht, Iran

2 Ph.D. Candidate, Faculty of Engineering, University of Guilan, Rasht, Iran

Abstract

Polymer modified concrete (PMC) consists of Portland cement concrete with a polymer modifier. Its advantages are proper bonding strength to substrate concrete, high tensile and flexural strength and low amount of shrinkage and permeability. Using PMC overlays can be considered as a method for preservation of damaged concrete structures due to their suitable performance and durability. In this research, 24 mix designs of polymer modified concrete as the repair overlay containing two different types of modifier polymers (Styrene butadiene rubber (SBR)-based and Acrylic-based polymers) with different replacement percentages and various amounts of silica fume was considered to investigate the effect of type and amount of polymers and also presence of silica fume. The in-situ strengths are obtained by the Pull-off Method in different conditions of presence of cores and without cores on cubic samples and without cores on repair overlays. The bonding strength of repair overlays to the substrate is also assessed and a formula is presented for prediction of bonding strength and in-situ strength by consideration mechanical properties.In both polymer modifiers, maximum bonding occurred in the presence of polymer with 20% of cement weight. SBR-based PMC showed stronger bonding compared to the Acrylic-based PMC.

Keywords

Main Subjects


[1] Barluenga, G.Hernandez, F. (2004),"SBR latex modified mortar rheology and mechanical behaviour", Cement and Concrete Research 34(3), pp. 527–535.
[2] Diab, A.M., Elyamany, H.E.Ali, A.H. (2014),"The participation ratios of cement matrix and latex network in latex cement co-matrix strength", Alexandria Engineering Journal 53, pp. 309-317.
[3]        Manson, J.A. (1976),"Modifications of Concretes with Polymers", Materials Science and Engineering,25, pp. 41-52.
[4]        Beushausen, H.Gillmer, M. (2014),"The use of superabsorbent polymers to reduce cracking of bonded mortar overlays", Cement & Concrete Composites,52, pp. 1-8.
[5]        Beushausen, H., Gillmer, M.Alexander, M. (2014),"The influence of superabsorbent polymers on strength and durability properties of blended cement mortars", Cement & Concrete Composites,52, pp. 73-88.
[6]        Rossignolo, J.A.Agnesini, M.V.C. (2002),"Mechanical properties of polymer-modified lightweight aggregate concrete", Cement and Concrete Research 32(3), pp. 329–334.
[7]        Rossignolo, J.A.Agnesini, M.V.C. (2004),"Durability of polymer-modified lightweight aggregate concrete", Cement & Concrete Composites 26(4), pp. 375–380.
[8]        Shaker, F.A., El-Dieb, A.S.Reda, M.M. (1997),"Durability of Styrene-Butadiene latex modified concrete", Cement and Concrete Research,27(5), pp. 711-720.
[9]        Dogan, M.Bideci, A. (2016),"Effect of Styrene Butadiene Copolymer (SBR) admixture on high strength concrete", Construction and Building Materials,112, pp. 378–385.
[10]      Momayez, A., Ehsani, M.R., Ramezanianpour, A.A.Rajaie, H. (2005),"Comparison of methods for evaluating bond strength between concrete substrate and repair materials", Cement and Concrete Research 35 pp. 748–757.
[11]      Brien, J.V..Mahboub, K.C. (2007),"Influence of polymer type on adhesion performance of a blended cement mortar", International Journal of Adhesion & Adhesives, pp. 7-13.
[12]      Courard, L., Piotrowski, T.Garbacz, A. (2014),"Near-to-surface properties affecting bond strength in concrete repair", Cement & Concrete Composites pp. 73–80.
[13]      Espeche, A.D.León, J. (2011),"Estimation of bond strength envelopes for old-to-new concrete interfaces based on a cylinder splitting test", Construction and Building Materials pp. 1222–1235.
[14]      Julio, E.N.B.S., Branco, F.A.B.Silva, V.D. (2004),"Concrete-to-concrete bond strength. Influence of the roughness of the substrate surface", Construction and building materials,18, pp. 675-681.
[15]      Julio, E.N.B.S., Branco, F.A.B., Silva, V.D.Lourenco, J.F. (2006),"Influence of added concrete compressive strength on adhesion to an existing concrete substrate", Building and Environment, pp. 1934–1939.
[16]      Mohammadi, M., Moghtadaei, R.M.Saman, N.A. (2014),"Influence of silica fume and metakaolin with two different types of interfacial adhesives on the bond strength of repaired concrete", Construction and Building Materials pp. 141-150.
[17]      Talbot, C., Pigeon, M., Beaupre, D.Morgan, D. (1994),"Influence of surface preparation on long-term bonding of shotcrete", ACI Mater J, pp. 560-6.
[18]      Saldanha, R., Jlio, E., Dias-da-Costa, D.Santos, P. (2013),"A modified slant shear test designed to enforce adhesive failure", Construction and Building Materials pp. 673–680.
[19]      Momayez, A., Ehsani, M.R., Ramezanianpour, A.A.Rajaie, H. (2005),"Comparison of methods for evaluating bond strength between concrete substrate and repair materials", Cement and Concrete Research,35(4), pp. 748-757.
[20]      Ghavidel, R., Madandoust, R.Ranjbar, M.M. (2015),"Reliability of pull-off test for steel fiber reinforced self compacting concrete", Measurement,73, pp. 628-639.
[21]      Sun, Z.Dillard, D.A. (2010),"Three-dimensional finite element analysis of fracture modes for the pull-off test of a thin film from a stiff substrate", Thin Solid Films,518(14), pp. 3837-3843.
[22]      ASTM,(2016) C33 / C33M-16 : Standard Specification for Concrete Aggregates., ASTM International.
[23]      Fowler, D.W. (1999),"Polymers in concrete: a vision for the 21st century", Cement & Concrete Composites, pp. 449-452.
[24]      Ohama, Y., (1995), Handbook of Polymer Modified Concrete and Mortars. William Andrew /NOYES PUBLICATIONS:  NY, USA,
[25]      ASTM,(2012) D7234 - 12 : Standard Test Method for Pull-Off Adhesion Strength of Coatings on Concrete Using Portable Pull-Off Adhesion Testers., ASTM International.