Rapid hardening high strength self-compacting concretes for the fortifications are developed in the article. A critical analysis of self-compacting concretes (SCC) for fortifications as high-tech mixtures demonstrates their advantages over traditional concretes. Improved technological, physical, and mechanical properties are achieved through the use of supplementary cementitious materials (fly ash, metakaolin, limestone powder) and their combination with effective polycarboxylate superplasticizer (PCE) and alkaline activator. SCC compositions are designed by mathematical modelling. The combination of pozzolanic additives, limestone powder, PCE and accelerator allowed to obtain rapid-hardening (fcm2/fcm28 = 0.55–0.57) and high-strength (C50/60) SCC with the required rheological characteristics, strength, and durability of SCC. The microstructure of the modified SCC cementitious matrix is dense due to pore colmatation by fly ash and pozzolanic reaction in the non-clinker part with formation low-base calcium hydrosilicates. The use of supplementary cementitious materials into the SCC composition improves environmental performance. The developed rapid-hardening high-strength SCC are characterized by high flowability, strength, increased crack resistance, which is importantin the production of fortifications.