In those of us in the concrete industry, the events over the last year have caused many of us to focus on the effects of blasts and fire on concrete structures. Information on the effects of fire on normal strength concrete (NSC) less than 7000 psi (50 MPa) has been available since the 1950s.1 On the other hand, little information on the behavior of high-strength or high-performance concrete (HPC) in fires has been developed until recent times, particularly with reference to thermal shock (high temperature rise rates) and sustained high temperatures.2