Response of SFRC Columns under Blast Loads

Abstract

Research has shown that the addition of steel fibers to concrete results in improved postcracking tensile capacity leading to enhanced toughness, ductility, and damage tolerance. These performance enhancements make steel fiber-reinforced concrete (SFRC) an ideal material for use in the blast-resistant design of structures. Research in the literature is conflicting on the performance of SFRC at high strain rates. There is also very limited research on the performance of SFRC structural components under blast loads. This paper presents the results of a research program investigating the blast performance of reinforced concrete and steel fiber-reinforced concrete columns. In the experimental program half-scale columns were constructed and exposed to different simulated blast pressure–impulse combinations using the state-of-the art shock-tube testing facility at the University of Ottawa. The test parameters included transverse reinforcement spacing (nonseismic and seismic detailing) as well as steel fiber content (0 to 1.5% by volume of concrete). The results show that SFRC improves the blast performance of columns in terms of maximum and residual displacements as well as damage tolerance and elimination of secondary blast fragments. Furthermore, the results demonstrate that the use of seismic detailing improves blast performance. Finally, the paper examines the suitability of using single-degree-of-freedom (SDOF) analysis to predict the blast response of the SFRC columns tested in the research program.