Effect of Natural Pozzolan on the Stabilization of Two Swelling Soils from the Western Region of Algeria

In recent times, a large number of studies have been carried out on swelling soils. It has been revealed that the swelling phenomenon, which still remains uncontrollable, is causing major disorders in several civil engineering structures around the world. The present study aims primarily to study the stabilization of two swelling clays. The first one comes from the region of M’zila, which is located in the Wilaya (Province) of Mostaganem, while the second is from the region of Bourmadia in the Wilaya of Relizane. This article also presents the results of geotechnical investigations that were carried out on two swelling soils that were treated with natural pozzolan (NP) from the town of Béni-saf, which is situated in north-western Algeria. The geotechnical parameters, such as consistency limits, as well as the proctor compaction test parameters and direct shear test parameters, along with the oedometer swelling test result analysis, were recorded and examined to evaluate the effects of adding different proportions of NP to these swelling soils. The results of the tests showed that several key properties of the above-mentioned soils were significantly enhanced after the introduction of NP. For instance, the rectilinear shear test at the Casagrande box showed that the cohesion coefficients of Bourmadia and M’zila soils containing 10% NP improved by 93.3% and 47.1%, respectively. In addition, the results of the oedometer test to determine the swelling potential indicated that NP was capable of inhibiting the swelling of both clay soils. Overall, the outcomes suggest that NP from the region of Béni-saf has remarkable potential for improving the geotechnical properties of expansive soils that are often encountered during the implementation of many civil engineering structures and construction projects.