Title: Elastic Design of Prestressed Sections in Flexure by Charts or Tables
Author(s): Witold W. Zawilski
Publication: Journal Proceedings
Appears on pages(s): 961-988
Keywords: no keywords
A method is presented for direct proportioning of the economical shape of cross section; trial and error effort is eliminated, and cross sections need not be modified. Principal concept of design is based on three simultaneous equations in three unknowns expressing loading and stressing conditions. The general equations presented are applicable to any kind of problem. A rapid design is demonstrated by using charts or tables exemplifiying the practical solution of such equations. The charts and tables are based on two fundamental principles of economical design: full utilization of concrete stresses; and full utilization of the lever arm of the internal resisting couple. Accordingly, two types of charts and tables are compiled: (a) for economical use of concrete; and (b) for economical use of steel. Finally, an economical design by charts and tables is developed for composite cross sections, particularly as applied to bridge decks.