This study investigates the influence of cement addition on the behavior of an expansive soil from Jordan. A wide range of cement content varying from 0 to 25% by dry weight of soil was used. This study shows that the liquid limit of the treated soil decreases drastically for cement content of up to 6%, then sharply increases for cement content in the range of 6 to 10% after which the liquid limit becomes practically constant. This study shows also that the swell potential of the treated soil decreases drastically for cement content of up to 4%, then sharply increases for cement content in the range of 4 to 6% after which the swell potential may decrease or may become constant depending on the initial water content. The undrained shear strength was generally observed to increase with the increase of cement content from 0 to 20%; however, the maximum rate of this increase was observed to be in the range of cement content from 6 to 10%. These results are interpreted in terms of cation exchange, flocculation and pozzolanic reactions that are associated with cement addition to soil
