Effect of flax shives content and size on the hygrothermal and mechanical properties of flax concrete

This paper presents an experimental investigation of the hygrothermal and mechanical properties of green concrete containing different content and size of flax shives. This allows it to respond to different applications in the building domain. Results of microscopic observations by using scanning electron microscopy show that the flax shives have a very complex and porous microstructure. The latter allowed for good hydric and thermal behaviour with a high moisture buffer capacity of which the minimum and maximum were 2.03 and 2.82, respectively. This allows it to be classified as an excellent moisture regulator. Flax concrete with a mass composition of 14.5% of flax shives in bulk, 35% of binder (tradical PF70) and a water-to-binder ratio of 1.45 gave a bio-based material with an average compressive strength of 0.8 MPa; it is, therefore, used as an insulation and filling material in buildings. (C) 2020 Elsevier Ltd. All rights reserved.