Kaymac Marine & Civil Engineering Ltd was commissioned by Centregreat Ltd to carry out the works as part of the new drainage layout to the residential development of Barry Waterfront
The works consisted of:
- Core drill suitably sized hole to accommodate concrete pipe through dock wall from pontoon at 2 locations.
- Rebate dock wall at both locations to accept flap valve.
- Fit temporary blanking plate at both locations while flap valves are fabricated.
- Removal of temporary blanking plates and installation of flap valves.
A pontoon and workboat were offloaded directly into the water by a Hiab Lorry and secured to the dock wall near the access steps using eyes bolts and ropes to prevent movement during drilling operations. The drilling equipment was then set up on the wall and polythene sheeting was secured between the pontoon and the wall to catch any falling debris and prevent it from entering the watercourse. Suitable plant nappies and spill kits were made available at all times in case of a leak or spill. A length of plastic guttering was fixed to the dock wall to collect any slurry run off from the drilling operations to later be disposed off site.
The core drill rig was set up at the required level on the dock wall by drilling and fixing the rig into masonry with mechanical fixings. Core drilling then commenced through the front of the masonry wall. When punch-out had occurred the small cores were removed and recovered to the surface. The remaining large central core was pulled though the wall from the other side using an excavator supplied by Centregreat.
On completion of the central core, a square measuring 1100mm x 1100mm was marked out on the dock wall around the hole which indicated the rebate area which was checked on site against the flap valve dimension. Using a hydraulic masonry saw, the square was then cut out to a depth of 200mm to accommodate the closed thickness of the flap valve. The spoil was placed in the buckets and removed for disposal off site.
The temporary steel blanking plate (with neoprene seals) was then lowered into position within the rebated square and drilled and fixed into position using suitable mechanical fixings. A suitable repair mortar was then used to fill up any gaps behind the steel blanking plate to ensure sufficient seal.
The above process was repeated at the second outfall location.
All items of non mechanical plant were removed from site. All Kaymac plant and equipment, and on hire equipment was demobilised by road transport from site.
Any excess materials were either disposed of off-site to a licensed waste facility, or returned to head office for re-use or recycling. Finally, all small tools and equipment were demobilised, any outstanding permits signed off, and following a housekeeping exercise, site personnel left the site in a clean and tidy condition.