Title: Evaluation of Retrofit of Beam-Column T-Joints in Older Reinforced Concrete Bridge Structures

Author(s): Laura N. Lowes and Jack P. Moehle

Publication: Structural Journal

Volume: 96

Issue: 4

Appears on pages(s): 519-532

Keywords: anchorage (structural); beams (supports); bridges (structures); joints (junctions); post-tensioning; reinforced concretes; shear properties

DOI: 10.14359/688

Date: 7/1/1999

Abstract:
Experimental tests and analyses investigated the seismic behavior of reinforced concrete beam-column T-joints. The test specimens were representative of interior beam-column joints in multi-column bridge frames constructed in California in the 1950s and 1960s. Three one-third scale models were tested, one representing the as-built joint and two representing retrofit joints. The as-built specimen had relatively little ductility capacity, whereas the retrofitted specimens exhibited improved performance. The nominal joint stress state, joint force-transfer mechanisms, and bond stress characteristics were investigated as a means of assessing joint behavior. The study clarifies the seismic behavior of lightly reinforced bridge T-joints and verifies a design procedure for retrofitting these joints.