Strength and Deformation of Pretensioned Box Girders

An analytical computer model is developed to analyze prestressed concrete box girders subjected to torque, bending moment, and shear. Its performance is evaluated in comparison with results of experimentation and current theory. Emphasis is placed on the prediction of post-cracking member deformations in addition to ultimate member strength. The analytical flexibility of the computer model is illustrated in contrast to the restrictive assumptions encountered in current theory. Being afflicted by only one serious shortcoming (which involves the variation of magnitude of the shear stress from the outside to the inside edge and which is not significant in box girders of common cross-sectional geometry), the computer model is a flexible, comprehensive mode of analysis whose range of application is limited by few constraints.