The double tee is a major production item of many integrated precast, prestressed concrete manufacturers in the United States. Thus, the shear reinforcement requirement by ACI-3181 and its omission by producers has attracted the interest of design engineers and prestressers alike. Since 1971, several companies have conducted tests on full size untopped or topped double tees.2 One of the authors conducted a test in 19863 related to shear mesh elimination. The test objective was to show that web reinforcement in the stems could be eliminated without impairing the flexural or shear capacities of' pretensioned tees. The test objective was met, and several producers invoked the provisions of Chapter 11, ACI-318, to waive the minimum area of shear reinforcement.
