Concrete’s extensive use in construction faces durability challenges, especially in environments with high sulfate levels, chloride exposure, or elevated CO2. This study examines how specific additives impact concrete’s performance and durability under these conditions. Experiments assessed concrete samples with varying compositions, focusing on additives that enhance strength and resistance. Plasticizers (0.1–0.5% of cement weight) slightly boost compressive strength (2–5%) and workability, indirectly supporting durability. Superplasticizers (0.2–2%) significantly enhance compressive strength (10–30%) and workability. Air-entraining agents (0.05–0.2%) improve freeze–thaw resistance but reduce compressive strength by 5–10 MPa. Silica fume (5–15%) increases compressive strength by up to 50% and enhances chemical resistance. Fly ash (15–40%) and Ground Granulated Blast Furnace Slag (GGBFS, 20–70%) improve long-term strength and durability, with GGBFS offering strong sulfate and chloride resistance. Metakaolin (5–20%) enhances strength (up to 30%) and chemical resistance, while limestone powder (5–20%) increases early strength but may decrease long-term durability. Nanomaterials (0.1–5%) and zeolites (5–15%) improve strength and reduce permeability, enhancing chemical resistance. Polypropylene and steel fibers improve toughness with minimal impact on compressive strength. Chloride-resistant admixtures are vital in harsh conditions, while bio-based admixtures enhance sustainability with variable effects on durability.