ii TECHNICAL REPORT STANDARD TITLE PAGE 1. Report No. 2. Government Accession No. 3. Recipient's Catalog No. FHWA/IN/JTRP-2003/5 4. Title and Subtitle Simplified Shear Design of Prestressed Concrete Members 5. Report Date August 2003 6. Performing Organization Code 7. Author(s) Robert J. Frosch and Tyler S. Wolf 8. Performing Organization Report No. FHWA/IN/JTRP-2003/5 9. Performing Organization Name and Address Joint Transportation Research Program 1284 Civil Engineering Building Purdue University West Lafayette, IN 47907-1284 10. Work Unit No. 11. Contract or Grant No. SPR-2798 12. Sponsoring Agency Name and Address Indiana Department of Transportation State Office Building 100 North Senate Avenue Indianapolis, IN 46204 13. Type of Report and Period Covered Final Report 14. Sponsoring Agency Code 15. Supplementary Notes Prepared in cooperation with the Indiana Department of Transportation and Federal Highway Administration. 16. Abstract Design methods for the shear resistance of reinforced and prestressed concrete beams are based on empirical evidence. Due to different approaches in their development different equations are used to calculate the shear strength of reinforced and prestressed concrete. Recent research conducted by Tureyen has proposed a simplified shear model for reinforced concrete which is primarily based upon mechanics and corresponds well with a wide range of test results. The objective of this research was to determine the applicability of the shear model to prestressed concrete. The applicability of the shear model was evaluated by a comparison of its results with the results of a database of 84 specimens which failed in shear. This analysis indicated that the shear model is applicable to prestressed sections. The shear model was simplified to develop an equation which is suitable for design office use. This equation is consistent with that proposed by Tureyen for reinforced concrete and unifies the design of these sections. As most prestressed sections designed are either T or I in shape, the research also investigates the use of the simplified design equation for these sections. Based on a comparison with test results, it is shown that the simplified design equation works well and provides a consistent factor of safety. A design example is presented to illustrate the differences between the proposed design equation and the current ACI 318 and AASHTO 16 th Edition provisions. Differences resulting from the different design methods are highlighted and discussed. As the proposed design equation requires calculation of the neutral axis depth, a simple hand-calculation procedure is also developed to approximate this value for prestressed sections. Finally, recommendations are provided for the proper implementation of the proposed method in design practice. 17. Key Words prestressed concrete, reinforced concrete, shear, shear strength, structural concrete. 18. Distribution Statement No restrictions. This document is available to the public through the National Technical Information Service, Springfield, VA 22161 19. Security Classif. (of this report) Unclassified 20. Security Classif. (of this page) Unclassified 21. No. of Pages 94 22. Price Form DOT F 1700.7 (8-69)