Mechanical Properties of Adobe Reinforced with Wheat Fibers in Iran (Persia)


Mechanical Properties of Adobe Reinforced with Wheat Fibers in Iran (Persia)

R. Nasiri, K. Ghavami, M. Kadivar, A. Maghami

Abstract. In adobe constructions, earthen blocks are made of a clayey-sandy-silt mixture with or without straw and/or additives. Based on a survey of traditional earth used in adobe constructions in Iran (Persia), the most commonly reinforcement’s fibers used are wheat straw, animal or human hair and some additives such as lime, hydrated salts, natural gum, and animal blood. In this study, the effects of some traditional amendments on the mechanical properties (Compressive, Bending and Tensile Strength) of adobes are investigated. The soil for the test samples is a mixture of sand, silt and clay which was taken from the mountain of the city of Yazd situated in center of Iran. Then the adobes were sun-dried without significant warping or cracking. Main considered variables were the percentages of the additives for establishing the best mixing trace. It has been observed that the strength of the adobe blocks increases significantly with the presence of straw and amendments. For a constant wheat fiber/soil ratio, the increase in additives increases the soil’s mechanical strengths including Compressive, Bending and Tension Strength. The optimum level of wheat fiber content was achieved with 50 percent of soil volume addition and the optimal level of lime content was achieved with 10%. However compressive, bending, and tensile strength increases with the increase in the natural gum contents.

Adobe, Natural Gum, Lime, Compressive, Bending, Tensile Strength

Published online , 10 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: R. Nasiri, K. Ghavami, M. Kadivar, A. Maghami, ‘Mechanical Properties of Adobe Reinforced with Wheat Fibers in Iran (Persia)’, Materials Research Proceedings, Vol. 7, pp 523-532, 2018


The article was published as article 50 of the book Non-Conventional Materials and Technologies

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