When concrete shrinkage has cracked the joint filler, it should be refilled with polyurea. Much of the debate about the recommended technique to properly fill control joints stemmed from the gain in market share and popularity of polyurea joint filler materials in the early- to mid-1990s.
A well-adhered, uncracked polyurea-filled joint. Polyurea joint fillers and sealants can significantly improve the performance and life of concrete control joints.
After overfilling the joint and letting the polyurea set, the joint filler is shaved off flush with the slab surface.
Polyurea joint fillers are easy to install. Polyurea has different physical properties than the traditional semi-rigid epoxies that were commonly used.
A concrete joint and its filler material undergo many stresses during the curing period of new slabs and that continues during its service life with ongoing shrinkage, thermal cycling, and traffic loads. Joints must be filled full depth to support the edges of the joint.