As bridges, parking ramps and other infrastructure components age, owners of these facilities often need innovative ways to repair concrete and mortar — filling voids created by spalling, cracking and chipping. Proper and timely repairs can extend the life of the facilities and avoid costly reconstruction and down time.
Methods for repairing concrete, mortar and other cementitious materials can vary from manual troweling to pumping-based methods. Hand troweling can be practical for small repairs but laborious for larger projects — and not always effective in areas with ridges and voids. As a more efficient alternative, pumping of cementitious materials can help increase production and handle challenging projects with difficult access.
In pumping applications, pre-blended cement-aggregate material is typically combined with water and other admixtures to provide a consistent repair mixture. The materials can be manually mixed with rotary drills in buckets or mixed with batch mixers using paddles. Portable pumps such as the Graco ToughTek M680 can be readily moved around job sites and pump gritty materials at pressures ranging from 200 to 500 psi, helping workers access otherwise hard to reach areas.
Portable pumps such as the Graco M680 can be readily moved around job sites.
For larger concrete and mortar repair projects, higher output can be achieved with units such as the Graco ToughTek P40. The P40 features a high-pressure pump capable of delivering 600 psi and pumping up to 3/4-inch aggregates. It can also pump longer distances, though the larger footprint may limit access to tight spaces. Even with the larger footprint, the unit still offers more portability than tow-behind units, which require additional setup and trailer-hitch-equipped vehicles for transport.
High-output pumps such as the Graco P40 provide additional capacity.
Regardless of pump size, pump-applied methods can vastly reduce transporting bulky materials around a job site and minimize staging locations. The pump does the work of delivering the material, instead of crew members moving back and forth from the mixer to the work area. This is also helpful when the mixing station cannot be placed near the repair, such as when scaffolding is required to reach the repair. With pumped mortar, workers can mix materials on the ground and pump up to the person on the scaffolding. With a smaller portable pump, workers can even place the pump on the scaffolding if needed and conditions allow. This allows for shorter hose lengths, less weight to transport, and it requires less cleanup.
Efficiently Making Repairs in Parking Garages
Parking garages have been key beneficiaries of mortar pumping. Material can be pumped into formed areas or sprayed freely overhead. With manual methods like forming and pouring or hand troweling, such repairs often require drilling down from above, potentially shutting down two levels of a garage. The level above the repair requires closure to pour the material into the form from above, and the level of the repair requires closure to construct forms and perform the repair.
Repairs to vertical components such as columns can also be handled with pumping. After a deteriorated area is identified, an area surrounding the deterioration can be cut out, reinforcement evaluated and repaired, and formwork established around the column with plastic, wood or steel forms. Cementitious material can be sprayed into spaces within formwork, as well as other areas without formwork. A similar process can also be used for overhead repairs.
Smaller, portable pumps can also be positioned close to the work areas, allowing the applicator to reach tight spaces and work close to the substrate. By using a portable pump with the correct materials, the amount of wasted material, rebound and cleanup can be minimized. This method can provide cost advantages over larger pumps and typical shotcrete.
To learn more about Graco's ToughTek mortar equipment, visit graco.com/toughtek.
*Claims or positions expressed by sponsoring authors do not necessarily reflect the views of TPC, Durability + Design or its editors.