Impact and blast behavior of seismically-detailed RC and UHPFRC-Strengthened columns

In order to investigate the blast and impact resistance of seismically designed and detailed RC columns, six RC columns (160 × 160 × 2468 mm) were constructed and tested using shock-tube and drop-weight impact test facilities. The influence of seismic detailing, with higher amounts of transverse reinforcement, was investigated. In addition, the effects of retrofitting using ultra-high performance fiber-reinforced concrete (UHPFRC) jacketing were studied. Non-linear finite element analyses were also carried out to predict the experimental results. The test results demonstrated that the use of seismic detailing improves the blast resistance of columns, resulting in reductions of the maximum and residual displacements at the mid height of the column, better control of cracks, and an ability to sustain larger blast loads. However, for drop-weight impact loading, the seismically detailed column did not show significant improvements in the tolerance to local damage and the control of displacements. In contrast, the use of UHPFRC jacketing in combination with seismic detailing showed excellent control of displacements and increased load carrying capacity under both blast and impact loadings.