Mechanical and Thermal Properties of Insulating Sustainable Mortars with Ampelodesmos mauritanicus and Pennisetum setaceum Plants as Aggregates

Abstract

The use of natural fibers in cement composites is a widening research field as their application can enhance the mechanical and thermal behavior of cement mortars and limit their carbon footprint. In this paper, two different wild grasses, i.e., Ampelodesmos mauritanicus, also called diss, and Pennisetum setaceum, also known as crimson fountaingrass, are used as a source of natural aggregates for cement mortars. The main purpose is to assess the possibility of using the more invasive crimson fountaingrass in place of diss in cement-based vegetable concrete. The two plant fibers have been characterized by means of scanning electron microscopy (SEM), helium picnometry and thermogravimetric analysis. Moreover, the thermal conductivity of fiber panels has been measured. Mortars samples have been prepared using untreated, boiled and Polyethylene glycol 4000 (PEG) treated fibers. The mechanical characterization has been performed by means of three point bending and compression tests. Thermal conductivity and porosity have been measured to characterize physical modification induced by fibers’ treatments. The results showed better thermal and mechanical properties of diss fiber composites than fountaingrass one and that fiber treatments lead to a reduction of the thermal insulation properties.

Lemongrass Plant as Potential Sources of Reinforcement for Biocomposites: A Preliminary Experimental Comparison Between Leaf and Culm Fibers

“…Overall, natural fibers with high cellulose content and small microfibril angles, having high crystallinity index, more compact and homogeneous morphology as well as low ash and water contents are the most suitable for the manufacturing of biocomposites with good mechanical performances [58,59].…”

Valorization of Pennisetum setaceum: From Invasive Plant to Fiber Reinforcement of Injected Composites

“…Among the first use, the cultivation of these plants in wetlands built for the treatment of wastewater has been investigated [8], as well as electrogenesis mediated by the rhizosphere of the plants [9]. Regarding the second use, it stands out for potential application as a natural aggregate for cement mortars (up to 30 wt% of fiber), using treatment with hot water [10]. However, this previous work concluded that a chemical treatment was needed to improve the compatibility between the cement and the fiber.…”