Predicting the Hygro-Mechanical Behaviour of Stabilized Compressed Earth Bricks

This study evaluates the influence of water content on the mechanical performances of stabilized compressed earth bricks (CEBs). Two clayey-rich materials were stabilized with 10% and 20% of lime-rich calcium carbide residue (0-20CCR). The stabilized CEBs were produced with the optimum moisture content of each mixture and cured for 45 days in ambient conditions. After the curing and drying, the CEBs were tested. Firstly, the water content was increased gradually, at an average step size of 5%, to evaluate the absorption kinetics and lately its effect on the physico-mechanical properties of CEBs. The CEBs showed rapid absorption kinetics from the first 20 to 30 min, before reaching a relative saturation of the CEBs. The increase in water content decreased the compressive strength. This evolution of the compressive strength with water content was fitted using a model proposed in the literature. By combining the water absorption kinetic with the hydro-compressive strength equations of CEBs, the evolution of the compressive strength was expressed with the time of bulk immersion in water. These results can allow us to predict the evolution of the bulk strength with respect to the rainfall time or other water absorption phenomena.