Influence of rubber aggregates from the recycled tires on the physico-mechanical and durability properties of compressed earth blocks

To meet sustainable development goals, global policies are strongly oriented toward valorizing alternative resources such as local materials and waste from different sectors of activity. This study aims to evaluate the influence of adding rubber aggregates from used/recycled tires (GPU) on the physico-mechanical and durability properties of compressed earth bricks (CEB). The CEB were made with an earthen matrix containing 8% cement, and 0 to 2% mass of GPU. The CEB were cured under ambient conditions (30±5°C) for 28 days. The results showed a real improvement in physical and mechanical performance and durability indicators of CEB with increasing GPU content. The apparent density changed slightly from 1697 kg/m3 to 1733 kg/m3. Total water absorption decreased from 21% to 19% with a slight decrease in water-accessible porosity from 35.7% to 33.1%. The capillary absorption coefficient at 10 minutes also decreased from 14 g/cm2.min1/2 to 10 g/cm2.min1/2 The increase of 29% was noted on the compressive strength in the dry state ranging from 3.5 to 4.5 MPa and of 60% on the compressive strength in the wet state ranging from 1.1 MPa to 1.7 MPa. This resulted in the improvement of the structural efficiency coefficient by 27% ranging from 2080 to 2651 Pa.m3/kg. Abrasion resistance coefficient increased more than 50% ranging from 10.8 to 16.9 cm2/g. By comparing the results to the normative references, the CEB containing GPU can be classified as CEB usable in load-bearing walls in a dry environment and resistant to abrasion.