Mechanical Compression and Crushing Properties of a Straw-Lime Material

Parmo Parmo (1) , Jean-Luc Hanus (2) , Naima Belayachi (1) , Patrice Bailly (2)

1 GC - Génie Civil
2 MMP - Mécanique des Matériaux et Procédés

The aim of this study was to determine the compressive mechanical properties and the energy absorption characteristics of a bio-composite material based on lime, wheat straw, and additives (protein and entraining agent). The selected samples with fiber to binder ratio of 30% were subjected to compression tests at different strain rates (1 mm/min, 10 mm/min, and 100 mm/min), in the perpendicular and parallel directions to fiber orientation. Image analysis supported with Digital Image Correlation (DIC) method is performed to follow longitudinal and lateral deformations, thus making it possible to evaluate elastic properties. The results show that the highest density and compressive strength in the parallel direction are ~349 kg/m 3 and ~0.101 MPa, respectively. The perpendicular specimens at 100 mm/min of speed test showed the highest values of densification strain, stress plateau, energy efficiency, and absorbed-energy of 47.27%, 0.32 MPa, 16.98 %, and 13.84 kJ/m 2 , respectively. The values of Young’s modulus identified with DIC are significantly different from those determined by the slope of the linear part of the stress-strain curve. A slight influence of strain rate on mechanical properties is observed.

Mots clés: Wheat straw; mechanical behavior; Poisson's ratio; Young's modulus; strain rate; compressive strength; energy absorption

Domaines: Génie civil

Parmo Parmo, Jean-Luc Hanus, Naima Belayachi, Patrice Bailly. Mechanical Compression and Crushing Properties of a Straw-Lime Material. Construction Technologies and Architecture, 2022, pp.227-233. ⟨10.4028/www.scientific.net/CTA.1.227⟩. ⟨hal-03807094⟩