Title: Flexural Anchorage Behavior in Diagonally Cracked Girders: Experiment
Author(s): Mary Ann T. Triska, Joshua K. Goodall, and Christopher Higgins
Publication: Structural Journal
Appears on pages(s): 263-274
Keywords: anchorage; bond stress; bridges; full-scale testing; reinforced concrete; shear
When load-rating the large number of diagonally cracked reinforced concrete (RC) deck-girder bridges constructed during the 1950s, the modern AASHTO LRFD check of flexural tension reinforcement anchorage can limit member ratings. The rating check compares the tensile demand in the reinforcing bar to the available tensile force at the section of interest. Among other parameters, the tensile demand is controlled by the diagonal crack angle at the section. The crack angles noted in inspections are generally flatter than those in the provisions and engineers are uncertain as to the inputs. The available tensile force in the flexural steel depends on the embedded reinforcing length; however, information is limited regarding bond stress developed with larger-diameter bars for full-size specimens. This research produced new flexural anchorage data in diagonally cracked girders that will help bridge engineers evaluate older concrete bridges. The results showed that the available bond strengths are higher than presently prescribed in ACI 318.