Many studies have shown that concrete structures are subject to varying degrees of deterioration due to chemical attacks, often associated with high soil salinity. As concrete generally exhibits low resistance to chemical aggression, it is sometimes necessary to implement protective measures on surfaces exposed to such harsh environments. This study investigates the effect of water-induced chemical aggressiveness on the degradation of concrete structures. It aims to evaluate the significance and effectiveness of protective measures applied to concrete exposed to aggressive environments, using an external epoxy coating and an internal water-repellent additive. Concrete specimens were exposed to both a normal environment and an aggressive one (Sebkha water from the Ouargla region in Algeria). The mixtures incorporated a water-repellent additive at a dosage of 2% by cement mass, using both of Portland cement resistant to sulfates (CEM I 42.5 N-SR 3) “CRS” and a Portland cement (CEMII /BL 42.5N) “CPJ”, with a constant water-to-cement (W/C) ratio of 0.61 for all mixes. The engineering properties evaluated include compressive strength, water absorption (by immersion and capillarity), and density for both protected and unprotected concrete in fresh and hardened states. In addition, the protective coating layers were characterized using scanning electron microscopy (SEM). Cubic and cylindrical specimens were tested at 28 and 90 days. The results show that concrete formulated with CPJ cement and the water-repellent additive exhibited superior compressive strength performance compared to the other specimens.
