Performance of Prestressed Concrete Roofs during Hurricane Andrew

Abstract

The paper presents some examples of prestressed concrete double‐Tee (DT) failures caused by Hurricane Andrew. The DT failures were mainly due to the negative moment created by uplift. In some instances a portion of the flange and the stem was torn away; in other cases the DTs collapsed altogether. The DTs were generally subjected to external as well as internal pressure when the overhead doors in these buildings collapsed. Most of the failures occurred in sections with shallower stems. The stress conditions in these DTs subject to hurricane winds are evaluated in the paper using local as well as ASCE design wind loads. In some instances the uplift was large enough for the beams to be airborne, because the anchorage provided was inadequate. Flange failures were also common where DT flanges were used as overhangs with sparse reinforcement. Also, many diaphragm shear connectors pulled out by spalling the small concrete cover provided.