Title: Analysis of the Flexural Strength of Prestressed Concrete Flanged Sections
Date: January-February, 2005
Volume: 50
Issue: 1
Page number: 74-93
Author(s): Eray Baran, Arturo F. Schultz, Catherine E. French
https://doi.org/10.15554/pcij.01012005.74.93
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Abstract
Inconsistencies in the sectional response of prestressed concrete flanged sections predicted by the AASHTO LRFD and AASHTO Standard Specifications, including the maximum reinforcement limits, may arise due to different interpretations of the equivalent rectangular compressive stress block idealization. Strain compatibility analyses with nonlinear material properties were performed for a variety of non-rectangular prestressed concrete sections to identify the inconsistencies between the two specifications. Responses of the sections obtained using nonlinear strain compatibility analyses were com pared to those predicted by the AASHTO LRFD and Standard Specifications. Modifications to the AASHTO LRFD procedure are proposed to correct for errors in determining the contribution of the top flange overhangs. Improvements in the accuracy of predicted sectional response are demonstrated through a parametric study. Comparisons of measured flexural strengths of prestressed concrete I-beams found in the literature to strengths predicted by the specifications, the proposed modified LRFD procedure, and the strain compatibility analyses are also included.
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