Performance of Alfa fibres in cementitious materials exposed to diverse surface treatments
Résumé
Alfa plant presents a great ecological and socio-economic interest in the Maghreb countries. It is used in several fields of applications such as craft production and paper industry. However, a few research work has been realized on the valorisation of Alfa fibres in the construction sector. The main objective of this work is to develop an Alfa fibre-reinforced mortar with significant mechanical properties for the facade panel’s manufacturing. It was highlighted that Alfa fibres enhance the flexural strength of reinforced mortars. Therefore, a decrease in the flexural strength of the composite after 90 days of curing. In addition, the incorporation of Alfa fibres reduced the compressive strength of the composite. In this regard, to enhance the mechanical properties of the composite, various treatments were explored: alkaline treatment with sodium hydroxide, hydrothermal treatment by water boiling, and coating with sulfoaluminate cement. It was noted that the treatments could provide a partial elimination of the non-cellulosic components and enhance the Alfa fibre roughness. Raw and treated Alfa fibres were incorporated into cement mortars at different lengths of the (10 and 20 mm) with an addition ratio of 1 %vol.. Compared to untreated fibres, fibres treated chemically provide an improvement of 38 % of the flexural strength at 28 days for both fibres length. Unlike the coated fibres, the efficiency of treatment was noted at 90 days of curing. Otherwise, a slight increase in compressive strength was observed compared to the untreated fibres mortar. These results were approved by porosity accessible to water and calorimetric tests.