Fire Damage Assessment, Pre-stressed Concrete Double-Tees at Parking Deck

This paper summarizes an investigative effort to determine the extent and severity of fire damage to lightweight precast pre-stressed concrete double-tee members at a parking structure. The study involved non-destructive evaluation techniques such as pulse velocity and radiography, as well as laboratory testing of concrete cores. Laboratory testing included determination of Dynamic Young's Modulus of Elasticity and Air Permeability Index on 25 mm. (1 inch) thick disks taken from cores, and determination of strength. Analyzing concrete specimens in 25 mm. (1 inch) thicknesses provided an insight into fire damage gradients. Based on the results of the first phase of testing, the structural elements were load tested. The load test produced a deflection pattern consistent with the findings of the testing program.