Triplet Shear Tests on Retrofitted Brickwork Masonry Walls

Authors: Berna Istegun, Erkan Celebi

Abstract:

The main objective of this experimental study is to assess the shear strength and the crack behavior of the triplets built of perforated brickwork masonry elements. In order to observe the influence of shear resistance and energy dissipating before and after retrofitting applications by using the reinforcing system, static-cyclic shear tests were employed in the structural mechanics laboratory of Sakarya University. The reinforcing system is composed of hybrid multiaxial seismic fabric consisting of alkali resistant glass and polypropylene fibers. The plaster as bonding material used in the specimen’s retrofitting consists of expanded glass granular. In order to acquire exact measuring data about the failure behavior of the two mortar joints under shear stressing, vertical load-controlled cylinder having force capacity of 50 kN and loading rate of 1.5 mm/min. with an internal inductive displacement transducers is carried out perpendicular to the triplet specimens. In this study, a total of six triplet specimens with textile reinforcement were prepared for these shear bond tests. The three of them were produced as single-sided reinforced triplets with seismic fabric, while the others were strengthened on both sides. In addition, three triplet specimens without retrofitting and plaster were also tested as reference samples. The obtained test results were given in the manner of force-displacement relationships, ductility coefficients and shear strength parameters comparatively. It is concluded that two-side seismic textile applications on masonry elements with relevant plaster have considerably increased the sheer force resistance and the ductility capacity.

Keywords: Triplet shears tests, retrofitting, seismic fabric, perforated brickwork, expanded glass granular.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1132170

References:

[1] Wallner C., “Erdbebengerechtes Verstärken von Mauerwerk durch Faserverbundwerkstoffe Experimentelle und Numerische Untersuchungen”, Ph. D. Thesis, Karlsruhe Institute of Technology, Karlsruhe, Germany, (2008).
[2] Korany Y. and Drysdale R., "Rehabilitation of masonry walls using unobtrusive FRP techniques for enhanced out-of-plane seismic resistance." Journal of Composites for Construction 10.3 (2006): 213-222.
[3] Rizzo, S., “Triplet Shear Tests on Pumice Blocks BLG19 with and without the Seismic Retrofitting System Röfix SismaCalce”, Final Report, Karlsruhe Institute of Technology, Department Reinforced Concrete, Karlsruhe, Germany, (2015).
[4] Beattie, G., Molyneaux T.C.K., Gilbert M. and Burnett, S., “Masonry Shear Strength Under Impact Loading”, 9th Canadian Masonry Symposium, Fredericton, NB, Canada, (2001).
[5] Corradi M., Borri A. and Vignoli A., "Experimental evaluation of in-plane shear behaviour of masonry walls retrofitted using conventional and innovative methods." Masonry International 21.1 (2008): 29.
[6] Lourenço P. B., Barros J. O. and Oliveira J. T., “Shear Testing of Stack Bonded Masonry”, Construction and Building Materials, 18, p.125-132 (2004).
[7] Alcaino P. and Santa-Maria H., "Experimental response of externally retrofitted masonry walls subjected to shear loading." Journal of composites for construction 12.5 (2008): 489-498.
[8] Oliveira, D.V.C., “Experimental and Numerical Analysis of Blocky Masonry Structures Under Cyclic Loading”, Ph. D Thesis, University of Minho, Portugal, 19-25 (2003).
[9] Münich J. C., “Hybride Multidirektionaltextilien zur Erdbebenverstarkerung von Mauerwerk; Experimente und Numerische Untersuchungen mittels eines erweiterten Makromodells”, Ph. D. Thesis, Karlsruhe Institute of Technology, Karlsruhe, Germany, (2010).
[10] Anglada, X. R., “Shear Tests on Masonry Triplets with Different Soft Layer Membranes”, B.Sc. Thesis, Swiss Federal Institute of Technology, Zürich, Swiss, 9-15 (2014).
[11] Magenes, G., P. Morandi, and A. Penna. "Enhanced safety and efficient construction of masonry structures in europe–d 7.1 c test results on the behaviour of masonry under static cyclic in plane lateral loads." Report ESECMaSE D s7 (2008).
[12] EN 1052-3, European norms for methods of test for masonry–Part 3: Determination of initial shear strength., 1996.