Evaluation of blast resistance and failure behavior of prestressed concrete under blast loading

In recent years, frequent terror and military attack by explosion and impact have occurred all over the world. Particularly, World Trade Center collapse and US Department of Defense Pentagon attack on Sept. 11 of 2001 and Fukushima nuclear power plant accident due to Northeast earthquake tsunami on the coast of Japan on Mar. 11 of 2011 resulted in devastating human casualties and structural collapses. These terrors and accidents raised public concerns and anxiety of potential structural collapse of major infrastructures and structures. In order to better combat these problems, the extreme loading resistant structural studies are initiated. Among numerous types of target structures, one of the most important structural types is prestressed concrete (PSC), which is widely used for construction of nuclear containment vessel and gas storage tank. In this study, to evaluate the blast resistance and protective capacity of bi-directional PSC member, blast tests were carried out on 1400 × 1000 × 300 mm reinforced concrete (RC), prestressed concrete without rebar (PSC), prestressed concrete with rebar (PSRC) specimens. The applied blast load was generated by detonating 25 kg ANFO explosive charge at 1.0 m standoff distance. The data acquisitions included blast waves of incident pressure, reflected pressure, and impulse as well as behavioral displacements of deflection, acceleration, and strains of concrete, rebar, and PS tendon. Then, the blast test results are used to calibrate finite element simulation model. Once the simulation model is calibrated, it is used to perform parametric study on bi-directional prestressed concrete specimens to further evaluate the blast resistance of the panels. The study results are discussed in detail in the paper.