Shear Strengthening of Concrete Structures with the Use of Mineral-Based Composites
Publication: Journal of Composites for Construction
Volume 13, Issue 1
Abstract
Rehabilitation and strengthening of concrete structures have become more common during the last , partly due to a large stock of old structures and partly due to concrete deterioration. Also factors such as lack of understanding and the consequences of chloride attack affect the need for rehabilitation. In addition, more traffic and heavier loads lead to the need for upgrading. Existing externally bonded strengthening systems using fiber-reinforced polymers (FRP) and epoxy as bonding agents have been proven to be a good approach to repair and strengthen concrete structures. However, the use of epoxy bonding agents has some disadvantages in the form of incompatibilities with the base concrete. It is, therefore, of interest to substitute epoxy with systems that have better compatibility properties with the base concrete, for example, cementitious bonding agents. This paper presents a study on reinforced concrete beams strengthened in shear with the use of cementitious bonding agents and carbon fiber grids, denoted as mineral-based composites (MBC). In this study it is shown that the MBC system has a strengthening effect corresponding to that of strengthening systems using epoxy bonding agents and carbon fiber sheets. Different designs and material properties of the MBC system have been tested. An extensive monitoring setup has been carried out using traditional strain gauges and photometric strain measurements to obtain strains in steel reinforcement, in FRP, and strain fields on the strengthened surface. It has been shown that the use of MBC reduces strains in the steel stirrups and surface cracks even for low load steps as compared to a nonstrengthened concrete beam.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The research presented in this paper has been funded by several organizations. The Swedish National Road Administration, The Development Fund of the Swedish Construction Industry, Skanska AB, and Sto Scandinavia are acknowledged.
References
BBK. (2004). Boverkets handbook about concrete structures BBK 04, Boverket, Sweden (in Swedish).
Becker, D. (2003). “Concrete slabs strengthened with carbon fiber composites.” Master's thesis, Luleå Univ. of Technology, Luleå, Sweden, 1402-1617 (in Swedish).
Blanksvärd, T. (2007). “Strengthening of concrete structures by the use of mineral based composites.” Licentiate thesis, Luleå Univ. of Technology, Luleå, Sweden.
Brückner, A., Ortlepp, R., and Curbach, M. (2006). “Textile reinforced concrete for strengthening in bending and shear.” Mater. Struct., 39, 741–748.
Carlsvärd, J. (2006). “Shrinkage cracking of steel fibre reinforced self compacting concrete overlays—Test methods and theoretical modelling.” Doctoral thesis, Luleå Univ. of Technology, Luleå, Sweden.
Carolin, A., Olofsson, T., and Täljsten, B. (2004). “Photographic strain monitoring for civil engineering.” Proc., FRP Composites in Civil Engineering, CICE 2004, Adelaide, Australia, 593–600.
Carolin, A., and Täljsten, B. (2003). “Theoretical study of strengthening for increased shear bearing capacity.” J. Compos. Constr., 9(6), 497–506.
Comité Européen de Normalisation (CEN). (2004). “Eurocode 2: Design of concrete structures—Part 1: Common rules for building and civil engineering structures.” prEN 1992-1, European Committee for Standardization, EC 2-1, Central Secretariat, Brussels, Belgium.
Courard, L. (2005). “Adhesion of repair systems to concrete: Influence of interfacial topography and transport phenomena.” Mag. Concrete Res., 57(5), 273–282.
Dilthey, U., Schleser, M., Möller, M., and Weichold, O. (2006). “Application of polymers in textile reinforced concrete—From the interface to construction elements.” Proc., 1st Int. RILEM Symp. Textile Reinforced Concrete, RILEM, Aachen, Germany, 55–66.
DIN EN. (2005). “Methods of testing cement—Part 1: Determination of strength”. DIN EN 196-1, Deutches Institut Fur Normung.
Monti, G., and Liotta, M. A. (2007). “Tests and design equations for FRP-strengthening in shear.” Constr. Build. Mater., 21, 799–809.
Nordin, H. (2003). “Fibre reinforced polymers in civil engineering.” Licentiate thesis, Luleå Univ. of Technology, Luleå, Sweden.
Nordin, H., and Täljsten, B. (2006). “Concrete beams strengthened with prestressed near surface mounted CFRP.” J. Compos. Constr., 10(1), 60–68.
Oehlers, D. J., Rashid, R., and Seracino, R. (2007). “IC debonding resistance of groups of FRP NSM strips in reinforced concrete beams.” J. Constr. Build. Mater., 22, 1574–1582.
Peled, A., and Bentur, A. (2003). “Fabric structure and its reinforcing efficiency in textile reinforced cement composites.” Composites, Part A, 34, 107–118.
Peled, A., Bentur, A., and Yankelevsky, D. (1998). “Effects of woven fabric geometry on the bonding performance of cementitious composites.” Adv. Cem. Based Mater., 7, 20–27.
Popov, E. P. (1999). Engineering mechanics of solids, Prentice-Hall, Upper Saddle River, N.J., 430–432.
Raupach, M., Orlowsky, J., Büttner, T., Dilthey, U., and Schleser, M. (2006). “Epoxy impregnated textiles in concrete—Load bearing capacity and durability.” Proc., 1st Int. RILEM Symp.: Textile Reinforced Concrete, RILEM, Aachen, 55–66.
Svanbro, A. (2004). “Speckle interferometry and correlation applied to large-displacement fields.” Doctoral thesis, Luleå Unive. of Technology, Luleå, Sweden.
Täljsten, B., and Blanksvärd, T. (2007). “Mineral based bonding of carbon FRP to strengthen concrete structures.” J. Compos. Constr., 11(2), 120–128.
Täljsten, B., Carolin, A., and Nordin, H. (2003). “Concrete structures strengthened with near surface mounted reinforcement of CFRP.” Adv. Struct. Eng., 6(3), 201–213.
Teng, J. G., Yuan, H., and Chen, J. F. (2006). “FRP to concrete interfaces between two adjacent cracks: Theoretical model for debonding failure.” J. Solids Struct., 43, 5750–5778.
Triantafillou, T. C., and Papanicolaou, C. G. (2006). “Shear strengthening of reinforced concrete members with textile reinforced mortar (TRM) jackets.” Mater. Struct., 39, 85–93.
Wiberg, A. (2003). “Strengthening of concrete beams using cementitious carbon fibre composites.” Doctoral thesis, Royal Institute of Technology, Stockholm, Sweden.
Information & Authors
Information
Published In
Copyright
© 2009 ASCE.
History
Received: Dec 13, 2007
Accepted: Jun 20, 2008
Published online: Feb 1, 2009
Published in print: Feb 2009
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.