Blast behavior of columns built with high-strength concrete and grade 690 mpa high-strength reinforcement

As part of this study a series of columns built with high-strength concrete and Grade 690 MPa high-strength reinforcement are tested under blast loads using a shock-tube. The performance of the columns is compared to a control set of specimens built with Grade 400 MPa reinforcement. In addition to the effects of concrete and steel type, the effects of longitudinal steel ratio and seismic detailing are also investigated. The results show that concrete strength has limited effects on blast behavior. Conversely, use of high-strength bars significantly enhances column blast performance by reducing displacements and increasing blast resistance, with an ability to reduce the required amount of steel reinforcement. The results further demonstrate that increasing the longitudinal steel ratio and seismic detailing improve the blast behavior of columns built with conventional and high-strength bars. As part of the analytical study the blast response of the columns is predicted using nonlinear single degree of freedom analysis and finite element modelling.