Effect of the Combining Use of Hydrated Lime and Shea Butter Residue as Stabilizers on the Compressed Earth Blocks Physical, Mechanical, Thermal and Hydric Properties

The use of soil as a construction material is limited due to climatic conditions such as rain and wind effects. The valorization of industrial and agricultural by-products in soil-material-based composites for construction materials is an alternative to producing eco-materials for building construction. This study evaluates the effect of Shea Butter residue (SBr) and hydrated lime (HL) as stabilizers on the performance of Compressed Earth Blocks (CEB). For the production of CEB specimens, firstly the dry mixtures were prepared using soil material and 5 wt% HL, 5% - 25% wt% SBr and secondly, the appropriate amount of water was thoroughly mixed with the dry mixtures using the result of the proctor compaction test. All the moistened mixtures were mechanically pressed into CEBs on mold size (29.5 cm × 14 cm × 9.5 cm), cured at ambient temperature in the lab for 0 - 45 days, and dried at 60？C for 7 days before being tested. The results give for the accessible porosity, bulk density, maximum dry and wet compressive strength, the respective value 31.58%; 1580 kg/cm²; 3.26 MPa and 0.75 MPa for CEB stabilized with 5 wt% lime without SBr. Moreover, the abrasion coefficient (14.49 cm²/g), the mass lost (0.08%), the surface depth (3.25 mm/h), the eroded surface (9.12 cm²), the sorptivity (0.046 g/cm²·min^1/2 the absorption by total immersion at 2 h and 24 h (4.06 and 11.94%) are best for the CEBs stabilized with 5/5 wt% HL/SSBr. However, the lower thermal properties were obtained with CEB stabilized with 25 wt% SSBr. We therefore observe the significant reaction between these industrial and agricultural by-products with the earth material, with effects particularly on the hydric, thermal and durability properties. The use of industrial and agricultural by-products such as lime and SBr at an appropriate rate of 5 wt% are suitable to improve CEBs performances.