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Many types of cracks can occur in prestressed double tees during casting, stripping, or shipment. The information in this article identifies cracks and lists causes and effects of the cracks, as well as what can be done to prevent or repair them. Cracks included in the article are: Flange cracks outside of stems--caused by insufficient reinforcement, binding during stripping, or mishandling during shipping; flange crack between the stems on opposite sides--caused by torsional stresses during stripping, handling, storage or shipping; horizontal end crack in stem--caused by improper design, release, stripping, handling or production; flange cracks on each side of stem--caused by improper or incomplete consolidation, improper stripping so that member is tilted, or volumetric changes during curing or drying; vertical crack at top of member--caused by excessive cantilevers, excessive eccentricity, vibration during hauling, hold-down device released prior to cutting strand; vertical crack at bottom of stem--caused by improper production, prestress, storage, handling, or bond failure; horizontal crack in stem--caused by excessive draping of strands, improper stripping, or improper production; diagonal cracks in stem-- caused by diagonal tension caused by sliding of member as prestress is released, excessive bearing stress on heel of member, sudden expansion due to heating, transverse movement, or improper production.