Calculating the nominal flexural strength of bonded prestressed concrete sections requires the solution of strain-compatibility equations, internal equilibrium equations, and material stress-strain relationships. Because numerical trial-and-error solutions to these equations are time consuming, approximate solutions are commonly used for design purposes. The general equations presented in this paper provide convenient, exact, and simple-to-execute solutions to the nominal flexural strength of prestressed concrete sections in accordance with the American Concrete Institute and American Association of State Highway and Transportation Officials design requirements. Examples illustrate the use of the equations and compare their results with examples in other technical literature. Examples are solved using Mathcad, which can be easily adapted to similar applications once the equations are entered into the program. Quadratic equations for the special cases discussed provide closed form solutions of the nominal flexural strength and are an appropriate replacement for code design equations.
