Dynamic performances of ultra-high-performance fiber-reinforced concrete-strengthened concrete columns subjected to blast impacts

Normal functionality of common concrete structures such as bridges and buildings relies heavily on the structural resistance under accidental or anthropogenic blast events. As one of the widely used structural types, reinforced concrete columns need to be highly considered when blast events occur to avoid severe socio-economic losses. To improve the blast-impact resistance of conventional reinforced concrete columns, this article makes the following contributions: (1) proposes to adopt the advanced ultra-high-performance fiber-reinforced concrete to strengthen the columns as a protective layer; (2) validates the superiority of ultra-high-performance fiber-reinforced concrete-strengthened columns through comparative study and specifies the controlling design parameters through sensitivity analysis; (3) implements and compares various ultra-high-performance fiber-reinforced concrete reinforcement methods; and (4) develops a numerical formula to predict the residual capacity of ultra-high-performance fiber-reinforced concrete-strengthened columns under blast impacts as a suitable alternate of the complicated and time-consuming finite element simulations.