Fire Safety Science Digital Archive

Current concrete design Codes raise concerns about concrete spalling during fire particularly under compressive stresses and high heating rates. High strength concrete columns would be more prone for explosive spalling due to their low permeability and high brittleness. This paper represents an experimental program on the behavior of high strength concrete columns under fire. The research includes testing reinforced high strength concrete columns subjected to various loading levels and heating rates. Eighteen columns were tested under four loading levels and two heating rates. The paper represents the main results including the measured concrete and steel temperatures and axial displacements. The paper includes also the results of testing extra 12 high strength columns executed to enhance the experimental program and to verify more precisely the effect of loading level on the structural performance of high strength concrete columns in fire. Valuable conclusions on the effect of loads and heating on concrete explosive spalling are shown in the paper.