Delamination of concrete structures is an area where injection can also offer selective repair. A prime example is bridge decks or other self supporting structures. The most common delamination is shearing of the concrete. This is commonly at the upper rebar mat.

 

Another common situation is hollow plane that develop when concrete bridge piers are resurfaced. Old piers are encased in new concrete. Hollow planes in this type of application are common, especially against smooth sections of the old pier. Cracking then occurs on the surface perpendicular to the hollow plane.

 

These delaminated area is subject to chemical penetration from the surface and moisture which may attack the reinforcing bar. If the delamination is not repaired, traffic will cause the area to pop-out by pounding on the delaminated upper concrete layer. Freeze-Thaw damage will also tear the concrete apart. The greater the number of freeze-thaws, the more water in the cracks during these free-thaws, the greater, and quicker the damage to the concrete.

 

Map delaminations by drag chain, hammer or sounding device. The damaged area requires no less than four (4) ports drilled for resin flow, depending on the size and shape of the delamination. This prevents the trapping of water that may be present.

 

The delamination is normally hollow planes that run along the reinforcing bar. When injecting the delamination, the resin will follow these hollow planed areas and can travel several feet in filling the voids.