Reuse of livestock waste for the reinforcement of rammed-earth materials: investigation on mechanical performances

Agricultural wastes as an additive within raw earth materials could improve the mechanical and physical properties of new sustainable construction materials and enhance waste management from a circular economy perspective. This study intends to fill the lack of knowledge considering the mechanical effects of animal fibres on rammed-earth materials. The effects of livestock waste, i.e., sheep wool fibre (SWF), as a reinforcing element in building components produced using raw earth and lime-free mortars have been evaluated. The samples were made by varying the wool content (0.25% or 0.50% weight) and the length of the fibres (from 10 mm to 40 mm). Linear shrinkage, flexural strength, compressive strength, and frac- ture energy were evaluated on samples incorporating SWF, to assess the effects of this waste addition on the mechanical performances of new bio-composite material. The best result of the flexural strength was 1.06 MPa, exhibited by samples made with the longest and highest percentage of fibres, 40 mm, and 0.50%, respectively. The average compression strength was about 3.00 MPa. The average energy fracture of the composite was 806.38 (N/mm).