Using lignocellulosic aggregates for preparing concrete
Résumé
The use of natural lignocellulosic aggregates like wood or plant fibers instead of mineral ones for preparing concrete is hampered by several factors, mainly the facts that natural aggregates are competing with cement for water, that they have lower mechanical properties and that the highly alkaline cement-water mixture is degrading the natural fillers, releasing sugars which are retarding cement hydration. All these three factors are leading to difficulties for preparing such concrete and are strongly decreasing their mechanical resistance. After reviewing the different treatments which have been proposed in literature, we will show that it is possible to prepare plant stem fragment reinforced concrete with suitable mechanical properties with and without pre-treatments when properly taking into account the release of sugars during the cement setting process, the effect of plant genotype and the role of cement composition.