Title: Strength and Serviceability of Shear-Critical Post-Tensioned Girders

Author(s): Sangyoung Han, Jarrod Zaborac, Jongkwon Choi, Anca C. Ferche, Oguzhan Bayrak

Publication: Structural Journal

Volume:

Issue:

Appears on pages(s):

Keywords: AASHTO LRFD; flexible filler; post-tensioned concrete member; post-tensioning; prestressed I-Girder; shear; spliced precast girder

DOI: 10.14359/51740847

Date: 5/31/2024

Abstract:
The results of an experimental program conducted to evaluate the performance of shear-critical post-tensioned I-girders with grouted and ungrouted ducts are presented. The experimental program involved the design, construction, and testing to failure of six full-scale specimens with different duct layouts (straight, parabolic, hybrid) and utilizing both grouted or ungrouted ducts. All tests resulted in similar failure modes, such as localized web crushing in the vicinity of the duct, regardless of the duct condition or layout. Furthermore, the normalized shear stresses at ultimate were similar for the grouted and ungrouted specimens. The current shear design provisions in the AASHTO LRFD Bridge Design Specifications (AASHTO LRFD) were reviewed and updated shear strength reduction factors to account for the presence of the duct in the web and its condition (i.e., grouted or ungrouted) were proposed. The data generated from these tests served as the foundation for updated shear strength reduction factors proposed for implementation in AASHTO LRFD.