Title: Experimental investigations on the initial shear strength of masonry with earth mortars

Authors: Patrick Fontana; Lorenzo Miccoli; Ulf Grünberg

Addresses: Division Building Materials, Bundesanstalt für Materialforschung und –prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany ' Division Building Materials, Bundesanstalt für Materialforschung und –prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany ' Division Building Materials, Bundesanstalt für Materialforschung und –prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany

Abstract: In this paper, a comparative study on the initial shear strength of masonry with earth mortars is presented. Triplet tests were carried out to characterise the shear bond strength of five different types of earth mortar, three purely mineral and two with vegetable additives (wood and straw chaff), using calcium silicate blocks. In spite of their lower bulk densities, mortars with chaffs reached a value of compressive strength comparable to the values shown by the purely mineral mortars. The characteristic initial shear strengths of all the tested earth mortars were between two and five times higher than the minimum values for initial shear strengths required by standards. To assess the influence of blocks pre-wetting, a comparison between calcium silicate blocks and earth blocks was performed to evaluate the results obtained from the standard test procedure compared to the more common practice of using earth mortars in combination with earthen blocks.

Keywords: earth mortar; sand-lime block; earth block; initial shear strength; shear bond test.

DOI: 10.1504/IJMRI.2018.089051

International Journal of Masonry Research and Innovation, 2018 Vol.3 No.1, pp.34 - 49

Received: 24 Mar 2017
Accepted: 13 Jun 2017
Published online: 04 Jan 2018 *

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