Blended lime plasters with biomass ash and natural fibres reinforcement

The possibility to valorise biomass combustion ash in air lime based plaster was evaluated by means of mechanical properties. The possible effect of vegetable fibres (hemp, flax) was examined as well. The biomass ash improved significantly the mechanical properties of plaster. On the other hand, the vegetable fibres are limiting the compressive strength due to lower wettability between fibres and lime. However the fibres had positive effect on bending strength, as it is expected. The surface modification of fibres seems to be necessary in order to improve their performance in the lime system.