Concrete Pontoons
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Marine Dock Systems Concrete Pontoon System The following information is provided to enable the appraisal of Marine Dock Systems (MDS) concrete pontoon system; also provided are comparisons with other pontoon systems on the market. The key elements of the Marine Dock Systems concrete pontoon system are as Flotation Modules • Flotation modules are one piece, rotationally moulded, U.V. Stabilized, high stress-crack and impact resistant polyethylene. They provide long life, low maintenance flotation which is not attacked by osmosis nor other chemicals found in the marine environment. The flotation modules are provided with the additional security of a polystyrene core, producing a positively buoyant, unsinkable system. Marine Dock Systems has pontoons and marinas in use now for over 20 years, with the flotation modules requiring No Maintenance. The advantage of rotationally moulded polyethylene is as follows: a) The outside skin of the module is in one (1) piece. A Marine Dock Systems (MDS) rotationally moulded skin is seamless and does not rely on glue or plastic welding for sealing the skin against the ingress of water or structural integrity. A variety of systems "wrap" a polystyrene block of foam with polyethylene sheeting or film. All the seams are then plastic welded or glued. The integrity of these skins is dependent on the quality of the welding and/or the adhesives. b) The minimum wall thickness of the MDS polyethylene skin is 5- 6mm. The moulding process also allows the build up of the wall thickness in the corners of the module. This maximises the structural integrity, impact, and abrasion resistance where it is required most. Systems using the polyethylene "wrap" and welded method don't usually have a polyethylene wall thickness greater than 2-3mm. Some are even as low as 0.5mm. Marine Dock Systems, Concrete pontoon system Page 1 of 3

Some systems use glued together, polystyrene foam blocks, which are then sprayed with a polyurethane, elastomeric covering. These systems are also relying on minimal coverage and thickness (less than 2mm) for sealing the skin against the ingress of water or structural integrity. Quite often, these skins can be damaged during transport. Marine organisms have also been known to damage and burrow through these sprayed on systems. The UV stability, stress-crack resistance and impact resistance of these sprayed on systems is generally not as good as Other systems on the market use a full...

Some competitors say that the thicker deck increases the height of the centre of gravity of the pontoon, which in turn reduces the pontoon stability. This is true, however stability is only a concern with narrow rectangular pontoons. "L" shaped and "T" shaped pontoons have adequate stability If a narrow rectangular pontoon is required, MDS can increase the stability of these pontoons with solid ballast in the bottom of the polyethylene float. Stability will not be a concern with a MDS pontoon. Flotation and stability calculations are always performed to ensure the pontoon is in accordance...