Plastic concrete, also known as flexible concrete, is characterized by its self-compaction, low cement content, and high deformation capacity. It is mainly used in Morocco for waterproofing dams. This research highlights the beneficial effect of CPZ-B cement enriched with natural pozzolans incorporated into plastic concrete. The addition of pozzolans aims to improve the rheological, mechanical, and durability characteristics of these concretes, while promoting the use of natural pozzolans in cement and reducing the proportion of clinkers, thus contributing to reducing the carbon footprint associated with cement manufacturing. This research focuses on the in-depth examination of plastic concrete used for flexible dams, including the recognition of components, especially CPZ-B cement, rheological tests, deformability analysis carried out by drained and undrained consolidated triaxial tests, measurement of deformation modulus using an extensometer, evaluation of permeability under constant load and determination of compressive strength. The modified Pinhole test was used to carry out erodibility assessments. The results show CPZ-B cement improves concrete rheology, enhancing deformability and watertightness of fresh concrete. These results also allow us to propose solutions to improve the formulation of plastic concrete, to increase their efficiency and longevity, and to expand their applications.