MECHANICS OF STRAW BALES FOR BUILDING APPLICATIONS

Author(s): T. Lecompte, A. Le Duigou
Paper category: Proceedings
Book title: ICBBM 2017 Proceedings of the 2nd International Conference on Bio-Based Building Materials
Editor(s): Sofiane AMZIANE and Mohammed SONEBI
e-ISBN: 978-2-35158-192-6
Publisher: RILEM Publications SARL
Publication year: 2017
Pages: 317-324
Total Pages: 8
Language : English

Abstract: During the last decades, straw bales have seen an increasing interest for building insulation and even for the construction of small load-bearing straw houses, especially in view of the need to seek low environmental footprints. Up to present, very few studies are available concerning the mechanical behaviour of straw bales in buildings. Nowadays hybrid timber and straw methods are taking over from simple load bearing structures. There is a lack of knowledge about the mechanical contribution of straw in such structures, as in load bearing configuration. This study aims at investigating the mechanics of straw bales by carrying out experiments on batches of substantial numbers of bales and observing their anisotropic behaviour. Compression models are proposed to estimate their behaviour in a load-bearing wall, which lead to some recommendations in terms of bale densities. The cross-comparison of experimental results shows that, in the density range 90-110 kg/m3, the elastic and strength characteristics are similar whatever the position of the bales (laid flat or on their edge). The mechanical behaviour of the straw bales is found to be influenced by the arrangement of straw and strings. When laid flat, the bales exhibit a particular type of deformation under single compression leading to a constant perimeter. In this position, the mechanical properties are controlled by two factors: (1) the packing density, induced by the machine during the baling process, and the elasticity and creep of the links; (2) the solid volume fraction of straw wisps, conditioned by the agronomic parameters and the pressure level in the baler.

Online publication : 2017
Publication type : full_text
Public price (Euros) : 0.00