Shear Capacity of CFRP Posttensioned Grouted Transverse Joints under Concentrated Loads

Abstract

The transverse joint between full-depth precast concrete panels in accelerated bridge construction (ABC) is a critical element for satisfactory performance of bridge decks. Live loads on bridge decks are caused by concentrated loads from truck tires. The shear capacity of new female-to-female grouted transverse joints constructed with precast concrete panels under concentrated loads was investigated and compared to experimental results. The experiments were carried out on transverse joints posttensioned with carbon-fiber-reinforced polymer (CFRP) rods and on non-posttensioned joints. A finite-element model was developed to determine stress transfer of concentrated loads at transverse joints. Two different design distribution widths were investigated based on (1) AASHTO recommendations and (2) finite-element analysis. Four methods were considered for calculating transverse joint capacity: shear friction, strut-and-tie model, principal tension stress, and a beam shear equation under axial compression. The shear friction method predicts the capacity with satisfactory accuracy for non-posttensioned joints and is conservative for posttensioned joints; the strut-and-tie model predicts the capacity of posttensioned joints with satisfactory accuracy.