Title:
Shear Strength Evaluation of Concrete Bridge Girders
Author(s):
Afshin Esfandiari and Perry Adebar
Publication:
Structural Journal
Volume:
106
Issue:
4
Appears on pages(s):
416-426
Keywords:
bridge(s); girders; shear strength.
DOI:
10.14359/56607
Date:
7/1/2009
Abstract:
A shear strength evaluation procedure for structural concrete girders that contain at least minimum transverse reinforcement (stirrups) is presented. The procedure is similar to the 2008 AASHTO LRFD shear design method except that it does not require trial-and-error for shear strength evaluation and provides more insight by providing information about different shear failure modes involving stirrups yielding, diagonal crushing of concrete, and longitudinal reinforcement yielding. To understand the background, predicted trends are compared with the modified compression field theory (MCFT) for the idealized case of an element subjected to uniform shear, and are compared to Response-2000 for beam elements subjected to combined shear and bending moment. To validate the proposed method, shear strength predictions are compared with results from strength tests on reinforced and prestressed concrete beams, as well as predictions from shear design methods in AASHTO LRFD and ACI 318. The procedure is used to evaluate the shear strength of girders in three existing bridges with prestressed concrete I-girders, prestressed concrete box-girders, and reinforced concrete channel-girders.