The growing importance of environmental efficiency in reducing carbon emissions has prompted scientists around the world to intensify their efforts to prevent the destructive effects of a changing climate and a warming planet. Global carbon emissions rose by more than 40% in 2021, leading to significant variations in the planet’s weather patterns. Nevertheless, a significant proportion of natural resources continue to be exploited. To prepare for this challenge, it is essential to implement a sustainable approach in the construction industry. Biobased materials are made primarily from renewable raw materials like hemp, straw, miscanthus, and jute. These new materials provide excellent thermal and acoustic performance and make optimum use of local natural resources such as agricultural waste. Nowadays, cement is one of the most important construction materials. In an attempt to meet this exciting challenge, biobased materials with low-carbon binders are one of the proposed solutions to create a more insulating and less polluting material. The aim of this review is to investigate and to analyze the impact of the incorporation of different types of biobased materials on the mechanical, thermal, and hygric performance of a mix using different types of binder.

Alfa plant (Stipatenacissima L.) and wheat straw fibers were investigated as reinforcement in cementitious matrix. The fibers were used separately in three states: raw, wet (by immersion in water) and alkali treated. A reference mortar without fibers and mortars with 1% and 1.5% by volume of the two different bio-fibers were used. The mechanical and physical properties of mortar specimens were studied as well as the morphological analysis was carried out after 28 days of curing. The results exhibit that both Alfa and Straw fibre addition changed the mechanical performance of mortars in comparison to the reference mortar. A higher porosity and water absorption were observed after the addition of raw and wetted fibers. The alkali treatment caused morphological changes that were proved more efficient. This treatment provided a good result in terms of mechanical and physical properties. Furthermore, the addition of 1% by volume of alkali treated fibers affords both mechanical and physical properties better than the control mortar. SEM micrographs confirmed the good fibers/matrix adhesion of the alkali treated fibers.

Alfa plants are endemic to the Maghreb, where they cover great areas and are of prime socio-economic interest. This study investigated use of the alfa plant in a fibre-reinforced cement composite for facade panels. Alfa fibres were ground in a knife mill, sieved through a 2 mm sieve and added to the mixture in different addition ratios (1, 2 and 3 vol%). The results showed that the incorporation of ground alfa fibres did not significantly influence the fresh properties of the mortar. Compared with a control mortar, there was a decrease of 4% in the workability of the mortar reinforced with 2 vol% of alfa fibres. An enhancement in flexural strength was observed for all three addition ratios, with the evolution of flexural strength linearly related to the increase of the fibre addition ratio. However, the compressive strength of the composites decreased with the addition of fibres, mainly due to the high porosity inside the matrix. This was confirmed by a capillary test, which showed that a high addition ratio led to high water absorption by capillary motion.