Experimental investigation of seismically resistant bridge piers under blast loading

This paper reports the findings of research examining the blast resistance of bridge piers that are designed in accordance with current knowledge and specifications to ensure ductile seismic performance. Blast testing was conducted on 1/4 scale ductile RC columns, and nonductile RC columns retrofitted with steel jacketing. The seismically designed RC and steel jacketed RC columns did not exhibit a ductile behavior under blast loading and failed in shear at their base rather than flexural yielding. A moment-direct shear interaction model was proposed to account for the reduction of direct shear resistance on cross sections when large moments are simultaneously applied. This made it possible to match and explain the experimentally obtained behavior when direct shear strength was compared with the shear demand obtained from plastic analysis.