Characteristics of Concrete Contact Stresses in Doweled Transverse Joints

Abstract

The triaxial state of concrete contact stresses that develop at dowel-concrete interfaces in dowel jointed concrete pavements is examined using detailed nonlinear three dimensional finite element (3DFE) analysis. The results are validated through comparisons with: (a) measured strains from laboratory-loaded doweled joint specimens; (b) computed bearing pressure using closed-form solution; and (c) field-measured dowel bending due to slab curling in an instrumented highway section in West Virginia, USA. A parametric study is conducted to investigate the influence of some design parameters on the magnitudes of concrete contact stresses. It is shown that the triaxial contact stresses include a tensile stress component that develop in concrete on both sides of a loaded dowel bar and may initiate small horizontal cracks that reduce load transfer efficiency of the doweled connection. A modified dowel design that reduces the intensity of concrete contact stresses is developed and its laboratory test results are described. The modified dowel design is being field tested in the newly constructed Robert C. Byrd's instrumented Highway section in Elkins, West Virginia, USA.

Keywords:

• Rigid Pavement
• Dowel Bar
• Finite Element
• Transverse Joints
• Contact Stresses
• Slab Curling