The valorization of Senegalese attapulgite clay in concrete, as a solution against the exhaustion of the cement deposits was studied. In that purpose, attapulgite was first calcined at 800˚C to make it reactive and added in concrete by substitution of Portland cement (CEM I 52.5N) at contents of 0, 5 and 10% by conserving a constant water/cement ratio value of 0.65. The effects of the partial replacement of cement by attapulgite on the physicochemical and mechanical properties of the concrete as well as on the steel-concrete bond were examined. For this purpose, the water porosity, the intrinsic permeability and the density of the clay-based concrete were evaluated. Compression, tensile and pull-out tests were carried out to determine the impact of clay on the Young modulus, the compressive and tensile strengths and the steel-concrete bond. This study was completed by a characterization of the pozzolanic reactivity of calcined attapulgite. All the results of these studies were compared with those of Portland cement as a reference. The substitution of cement by attapulgite up to 10% in concrete has only a small influence on its porosity and permeability and confers to the concrete gain in compressive strength of 11%. However, it caused a loss of steel-concrete bond of 10%.

The study deals with the use of attapulgite as a corrosion inhibitor of two metals, namely aluminum and zinc, and their alloy (aluzinc), in a 0.5 M hydrochloric acid medium. The study was carried out by monitoring the free-corrosion potential and performing dynamic polarization measurements (Tafel curves) at different concentrations of inhibitor in solution. The measurements suggested that in a 0.5 M acidic medium, the surface of each of the three materials was attacked. The decrease in current density was very noticeable in aluminum and zinc at a level of 2 g×L-1. A weak tendency to passivity was noticed for zinc and aluzinc. The experimental results obtained showed a decrease in the current intensity in the presence of the corrosion inhibitor in the acidic medium. The maximum inhibitory efficiency rate reached for the metals and their alloy was higher than 99 %. This percentage was obtained for aluminum and zinc in the presence of 4 g×L-1 of attapulgite and 3 g×L-1 for aluzinc.