The extent of corrosion damage to car parks often reveals itself mid-way through a major refurbishment. Operators need to keep corrosion levels in check or else pay the price
At a time like this, operators don’t have the money to invest in new developments. Instead, they are refurbishing current schemes to make them last well into the future. And the most effective way of improving a car park’s longevity is to tackle the source of the problem – corrosion.
Corrosion causes the most significant damage to concrete structures over time, and as car parks age they become more and more costly to repair. Many structures have suffered from the effects of concrete carbonation and other corrosive factors over several decades, making any reparations a huge part of total costs.
The 1960s material of choice in car park construction was reinforced concrete. However, years of weathering and the use of de-icing salt have eroded the infrastructure, causing the decking to crumble and leaving car parks weak and unsafe. Having seen the effects of the last 40 years on British car parks, safety barrier company Berry Systems has been working to provide operators with viable solutions.
As Simon Bradbury, marketing manager at Berry Systems, puts it: “Many of the country’s 4,000-plus multi-storey car parks were originally built in the 1960s out of reinforced concrete, and refurbishing these can reveal some nasty surprises and additional costs. Several cases of concrete cancer have been reported and although complete structural collapses are rare, they are not unknown.”
Last year, the Patriotic Street multi-storey car park in St Helier went through a refurbishment to counter the effects of corrosion on concrete walls around the edge of the building. This, according to Bradbury, is a common problem in 1960s constructions.
“Over the years these walls have sustained impact damage but, more crucially, they may have been exposed to the elements. Constructed to the normal building standards of the time, it is now recognised that they are actually subject to a much more severe environment – perhaps more akin to that of bridges,” explains Bradbury.
“Deterioration from reinforcement corrosion brought about by the effects of de-icing salt has resulted in many perimeters becoming dangerously ineffective.”
The deck of the Patriotic Street car park was too crumbly to hold a typical barrier post, so instead spring steel posts were used. Designed by Berry Systems to bend and absorb any impact, these posts do not need to be embedded deeply into the deck – a necessity when corrosion has had a severe impact.
Although solutions such as these are a valuable investment when the decking has already deteriorated, the most cost-effective way of dealing with corrosion is to catch it before it becomes a serious issue. Many car park refurbishments, therefore, incorporate monitoring equipment that allows operators to keep a close eye on any potential problems.
Matrix Solutions, the car park refurbishment specialist, has been encouraging a proactive stance towards car park maintenance over the last decade. During the substantial refurbishment of a multi-storey car park in Southampton, Matrix buried electrodes under areas of the deck where the risk of corrosion was especially high.
Tim Whittaker, marketing director at Matrix, is aware of the present need to reduce spending and manage future costs more efficiently. “We appreciate that, in the current economic climate, many clients are looking for value engineered solutions which often do not involve structure-wide applications of specialist coatings. Where this is the case, we have developed a unique range of asset management solutions focused on monitoring the condition of the structure,” he explains.
For the council-run Eastgate Street car park in Southampton city centre, Matrix compiles an annual corrosion report based on information from reference electrodes embedded in the concrete. “This allows the management surveyor to regularly monitor the condition of their client’s car park, and also predict more accurately future repair and maintenance requirements,” adds Whittaker.
This wasn’t the only solution to be implemented during this particular refurbishment. Matrix also applied deck coatings and an anti-carbonation treatment to help fight against corrosion damage. But Neil Wright, managing director of Matrix, emphasises that corrosion monitoring worked effectively as an after-care service in this case. “We felt that to provide the client with the additional longevity they required, the ability to remotely monitor any future corrosion activity added significant value to our solution,” he says.
Eastgate Street multi-storey car park, built in the 1960s, is frequently used by people shopping in the nearby Bargate, Marlands and East Street shopping centres, as well as WestQuay retail park. With such a high usage, Jas Sahota, technical manager of parking services at Southampton City Council, wanted to invest in the long-term maintenance of the car park.
“The corrosion monitoring was installed to ensure that we are aware of any issues arising; to avoid any potential problems; and to allow us to carry out a planned maintenance approach if required,” says Sahota.
So this monitoring solution not only helps operators stay one step ahead of any major problems, it also assists with plans for the future. With annual updates on corrosion damage to specific areas of the car park, operators can learn more about the cause of corrosion and tailor maintenance plans to suit their findings.
In Horsham, Pyle Car Park Consultants have been working with the district council to extend the life of the Swan Walk multi-storey car park by 50 years. The car park, situated next to Swan Walk shopping centre, was another 1960s build suffering from years of corrosion. But Russell Simmons, project manager at Pyle Consulting, says that the concrete will now be closely monitored to give a better idea of future corrosion levels based on previous patterns.
“Each and every repair is logged with details of anodes, any additional steel work installed and the exact location of the repair for reference over the life of the structure,” says Simmons.
With monitoring systems recently implemented at car parks in Southampton and Horsham as well as Wakefield and Oldham, is the recession having any impact on the uptake of corrosion monitoring? Not necessarily, according to Whittaker, but money is certainly a factor.
“Clients have been, and are still, looking for even more value for money. We have found that once a client understands the significant benefits of corrosion monitoring, and that it can be incorporated into a major refurbishment or as a stand-alone solution, they are keen to include it within their maintenance regime and life care planning process,” he says.
As car parks will continually need refurbishing and maintaining, there will always be a need for corrosion solutions. But crucially, monitoring equipment can be employed in older constructions as well as new builds because it simply involves embedding electrodes within the decking. This is not the case with barrier or reinforcement added after damage has been done, because the decking must be strong enough for posts to be inserted which is not always the case. Columns are also difficult to design for existing car parks because they must be able to withstand the correct amount of pressure. And any barriers constructed around the edge to bolster corroded walls will impinge on the space inside the car park.
So corrosion becomes incredibly costly for operators of existing structures, and sometimes impossible to repair without tearing down the infrastructure and starting from scratch. For these reasons, Whittaker believes that monitoring in particular will become a major tool employed in many 1960s constructions as well as new builds.
“If a shopping centre owner has a revenue-generating car park or an asset of considerable value, surely it is in their interest to be able to monitor future corrosion and act before repair costs spiral out of control.
“Annual maintenance budgets are regularly exceeded due to reactive repairs not addressing the issue at source – corrosion. Being able to proactively monitor this and act accordingly delivers far more cost certainty to owners and managers when it comes to maintaining their car parks,” he says.
