Variability Assessment of the Compressive and Tensile Strength of Fibred Earthen Composites

Abstract:

Earthen composites (rammed earth, cob, adobe, daub, CEB...) are experiencing renewed interest from builders due to the many advantages of these building materials, and in particular their eco-friendliness. Nevertheless, the widespreading of these materials, as certified materials and conforming to construction standards, comes against the lack of data concerning their mechanical properties. Indeed, the literature generally gives the average values of the properties without indicating the number of specimens tested neither the distribution of the data. Yet, the mean value of the compressive strength is not enough to assess the reliability of a given earthen composite to build a wall and it would be better to indicate the value of a defined percentile (characteristic value just like with concrete composites). The aim of this paper is to analyze the data about the mechanical properties (tensile and compressive strength) obtained on different formulations of cob including natural fibres or not. The tests performed allowed to determine the probability density function and the average values, the standard deviation and the percentiles, for the various properties.

• Periodical: Construction Technologies and Architecture (Volume 1)
• Pages: 612-619
• DOI: https://doi.org/10.4028/www.scientific.net/CTA.1.612
• Online since: January 2022
• Authors: Philippe Poullain*, Mircea Barnaure, Stéphanie Bonnet
• Keywords: Compressive Strength, Earthen Composites, Fibre, Probability Density Function, Standard Deviation, Tensile Strength

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