Multicriteria analysis of hemp particles’ impact on physical and thermo-mechanical performances of hemp concrete

Abstract

The hemp concrete is considered as an eco-material due to its environmental assets. Its constituents are mainly the hemp particles, binder and water to which admixtures are added eventually. The quality of hemp particles is very sensitive to the nature of soil where it is produced and also to its transformation process, which results in properties variability of hemp particles. And this may be a barrier to development of hemp concrete industry. The herein study aims to evaluate scientifically the impact of this variability on hemp concrete performances. This study is carried out through two main steps: (1) predicting the impact of hemp particles on the hemp concrete, (2) hemp concrete characterization. In the first step, a multicriteria analysis (particle size distributions, etc.) highlights the significant variability of the hemp particles and allowed to classify them into three groups. In the second step, the tests carried out on hemp concrete resulted in low, medium and high mechanical performances as predicted. A factor close to 10 is observed between the minimum and maximum compressive strengths. However, the density and the thermal conductivity are of low variability. The performed analysis show that the interaction between the hemp particles and the binder is likely to contribute to the mechanical response.