Full depth hydrodemolition concrete removal can easily be performed using Rampart’s ultra-high pressure (UHP) waterjets working at 35,000-psi and 32-48 gpm. Our equipment and ultra high water pressures allow us to remove up to sixteen (16) inches in a single pass.
Full depth deck removal (Fig. 1) is specified to minimize damage to precast and hollow core beams. Existing deck reinforcing steel, including reinforcing that extends from the precast beams into the slab, is not damaged during the concrete removal. In cases of waffle slab (Fig. 2) or pan-joist construction, hydrodemolition removes the entire top surface without damaging or fracturing the joist.
Full depth removal can be limited to certain sections of deteriorated slabs or where cracks have penetrated the entire depth and chloride contamination may have occurred full depth. The existing reinforcing is undamaged and it is much quieter than mechanical, impact methods.
We can remove concrete around expansion joints without damaging the hardware or reinforcements (Figs. 3 and 4). Hydrodemolition can expose all reinforcements at the slab edge to allow splicing new rebar when joining a new slab to an existing slab.
When it comes time to replace the bridge deck, our equipment can be used to completely remove concrete over bridge deck beams without damaging the beam and shear studs (Fig. 5). The reinforcing can then be cut and the slab picked off the beams.
We have also successfully removed concrete infill from steel grid decks giving contractors easy access to welds between the grid and structural beams.
Often the concrete element will exceed the typical 8-10” thickness. During deep removal hydrodemolition, concrete up to 16” can be removed in a single pass. After removing reinforcing or embedded objects, we can repeat the process until the full thickness of the reinforced concrete section has been removed. To date, our record is 72 inches.
Rampart has also prepared openings or penetrations in structural concrete in dams, locks, and nuclear containment buildings.