Characterization and comparison of hygric properties of rape straw concrete and hemp concrete

The use of plant particles as aggregates in construction materials provide a very good hygric performance, and offers a real contribution to sustainable buildings. This paper focuses on the hygric properties of a new bio-based material called “rape straw lime concrete” in comparison with a “hemp lime concrete” which is used to validate the experimental protocol of this work. The tests are conducted on the sorption isotherm, the water vapor permeability, the capillary water absorption and the moisture buffer capacity which is estimated from the moisture buffer value determined under equilibrium condition. The results showed that the materials have very interesting hygric properties and exhibit an excellent moisture buffer capacity.