The behavior of aggregate interlock joint systems in PCC pavements is being studied. The monotonic and cyclic shear behavior of the joint is being quantified through the use of the joint's surface roughness characteristic. The surface roughness of the concrete joint is being characterized by a 2-D laser profilometer, which represents the 3-D contours of the joint surface. Scale invariant parameters are being developed to relate surface roughness to the joint performance and concrete mix design variables such as the compressive strength, aggregate type, hardness, and gradiation

This research will help to characterize and improve the joint design in concrete pavements.