Grouting is part of the Foundation Installation scope. Grouting is required in the following cases:
(1) Grouting between Monopile and Transition Piece
(2) Grouting foundation piles to Jacket Sleeves
(3) Grouting void above suction pile foundations
Grouting for offshore wind project is done using a dedicated vessel.
A CSV (Construction Support Vessel) is required with 2000 m2 deck, 300 t crane AHC preferred, Dynamic Positioning.
Grouting operations are usually independent from other Installation activities, thus grouting activities are not in the Critical Path and rarely affect the overall construction time.Personnel organizational Chart …… add here
List required teams onboard
Marine Operations Manager (overall)
OCM on board the CSV reports to
Mobilization Location
Mobilization should take place at r the grouting campaign will take place. The exact location/quay will be selected based on availability.
Mobilization Planning
Equipment and Material
1.1 Typical Grouting Spread –
The grouting subcontractor will provide the equipment required. Below is a list of a typical grouting spread:
Equipment/Material | Number | Weight | Dimensions |
Grout Mixer | 1 | 12 t | 20 ft container |
Workshop Container | 1 | 12 t | 20 ft container |
Refrigeration Unit | 1 | 5,5 t | 20 ft container |
Sodium Silicate Storage Tanks | 4 | 30 t | 20 ft container |
ISO Cement Silos | 6 | 27,5 t | 20 ft container |
Cement in vessel Dry Bulk, 6x54t=324 t | Total | 324 t | Vessel Dry Storage |
Silicate Pump | 1 | (TBD) | (TBD) |
Heating Elements | 2 | (TBD) | (TBD) |
Air compressor | 1 | (TBD) | (TBD) |
Waste Skips | 2 | 1,4 t | 4x2x1,5 m |
Grouting Hose (Delivered in Pieces) | 200 m | – | – |
Notes:
- Cement (462 t). The cement is delivered from local suppliers in 26-30 t per load. Each load will take approximately 1 hour to unload. Cement will be stored in vessels dry bulk tanks (324 t) and in to six ISO silos on deck (6x23t=138t). Loading time for 462 tons of cement will be 17 hours (17 lorries).
- Sodium Silicate (102 t). Core will provide 4 No. ISO Tank Containers for storage of Sodium Silicate onboard the installation vessel. Sodium silicate will be transferred from the delivery truck to the ISO tanks at the quayside. The ISO tanks will then be lifted onto the vessel using the spreader frame supplied by Core.
Seafastening Containers (1) HEB200 Beams, L=10.5 m. Fitted with twistlock sockets, wingplates and stiffeners. | 6 pcs | 0.7 t |
Seafastening Containers (1) HEB200 Beams, L=7 m. Fitted with twistlock sockets, wingplates and stiffeners. | 2 pcs | 0.45 t |
Bunded area fabrication material Steel Plates 3 mm, UPN100 beams. | – | – |
Spare Steel Material: – Seafastening plates (20x) – D-rings 3-5t (10x) – UPN100, L=6 m (1x) – L50x50x5mm, L=2m (6x) – 15 mm plate (approx. 1m2) (1x) – Round bar D=20 mm, L=2m (6x) – 1½ in pipe SCH40, L=2m (2x) – 6in pipe SCH40, L=2m (2x) – Wire Rope D=5-7mm (L=5m) | Total | 0.3 t |
Grouting Hose deployment auxiliary – polypropylene rope 8 mm – 24 x buoys – 20x Caribinas – bend stiffener for hose – hose saddle c/w lifting point | – | – |
2t Drop Bags (gravel) – if scour protecting is installed | 110 pcs | 2 t |
Contractor project team will arrange for:
- Offloading equipment on quayside
- Secure storage area for equipment/material until they are lifted on board the installation vessel.
- Procurement and installation of seafastening
- Procurement and installation of bunding around the perimeter of the waste skips and mixing
- Procurement of Drop Bags (gravel).
1.1 Deck Layout
A typical Deck layout is shown in the Figure below. Material and equipment on deck are fitted in ISO containers. Foundation beams will be installed on deck and container will be secured with twist locks. Miscellaneous equipment will be seafastening will alternative means (dog plates, lasting).
ESTIMATED GROUTING CYCLE – TASK DURATIONS Breakdown
Task Description | Duration |
Sailing to Location | ?? hrs |
DP Trials and Positioning | 2 hrs |
Deck and ROV preparations | 2 hrs |
Launching ROV | 0.5 hrs |
Grouting bucket voids at Leg A | 7.5 hrs |
Grouting hose deployment | 1 hr |
Connection to manifold and opening valves | 2 hrs |
Mixing, pumping, monitoring, closing valves | 2 hrs |
Disconnect from IN 2 and connect to IN 3 | 0.5 hrs |
Grouting void above bucket | 0.5 hrs |
Close valve IN 3 and disconnect hose | 0.5 hrs |
Flush and retrieve hose | 0.5 hrs |
Shift vessel and reposition for grouting Bucket Leg B | 0.5 hrs |
Grouting bucket and voids at Leg B | 7 hrs |
Grouting hose deployment | 0.5 hrs |
Connection to manifold and opening valves | 2 hrs |
Mixing, pumping, monitoring, closing valves | 2 hrs |
Disconnect from IN 2 and connect to IN 3 | 0.5 hrs |
Grouting void above bucket | 0.5 hrs |
Close valve IN 3 and disconnect hose | 0.5 hrs |
Flush and retrieve hose | 0.5 hrs |
Shift vessel and reposition for grouting Bucket Leg C | 0.5 hrs |
Grouting bucket and leg voids at Leg C | 7 hrs |
Grouting hose deployment | 0.5 hrs |
Connection to manifold and opening valves | 2 hrs |
Mixing, pumping, monitoring, closing valves | 2 hrs |
Disconnect from IN 2 and connect to IN 3 | 0.5 hrs |
Grouting void above bucket | 0.5 hrs |
Close valve IN 3 and disconnect hose | 0.5 hrs |
Flush and retrieve hose | 0.5 hrs |
Retrieve ROV | 0.5 hrs |
Shifting and positioning to next foundation | 1.5 hrs |