65 Years Of Marine Refurbishment
Concrete marine structures are often continually exposed to extreme environments such as tidal seawater, wave action, storms and ship damage. Chloride ions from the marine environment migrate through the cover concrete and in sufficient concentration at the steel reinforcement will initiate local severe corrosion of the reinforcement. If left untreated this can cause significant deterioration in the structure eventually leading to failure.
CRL have extensive experience of refurbishing client’s marine assets with regards assessing the scope of works and advising on the optimum form of access (which is key to successful operations on the structure taking into account tidal movement and environmental constraints). CRL have used scaffold, cradles, pontoons, bespoke solutions for low head room and steel framed structures for longer duration projects.
If required, we can undertake the initial condition survey of the marine structure which is critical to the success of the subsequent repair contract. Ports Australia published "Wharf Structures Condition Assessment Manual" in 2014 and we recommend that Clients use this as the template for the survey works.
Typically, high strength concrete will need to be broken out, often in large quantities. This lends itself to the use of hydro demolition. Environment considerations may dictate the entrapment and treatment of the water, as well as suitable containment from a safety perspective.
The defective areas of concrete are reinstated using hand placed mortars for small repair areas, sprayed concrete or shutter and pour using a flowable repair concrete. We are approved applicators for all the leading material suppliers in Australia and can select the most suitable materials to meet the Client's requirements.
With high chlorides from the marine environment there is a high risk of steel reinforcement corrosion.We can design and install cathodic protection systems which reduce the risk of further corrosion for a further 50 years. We have corrosion control systems running for over 25 years that continue to provide protection to marine structures worldwide.
For steel piles and sheet piling we use a combination of barrier coatings above the mid tide level and cathodic protection using galvanic or impressed current anodes below mid tide level.
Timber piling can be repaired using wrap systems specifically developed to maintain and strengthen marine piles.
CRL also undertake miscellaneous works often found on marine structures, such as;
- Refurbishment of chains, Hi- Dacs and fender support systems, and
- Pipework slung beneath jetties.