Asphalt transformed to Caithness slate in Union Street trick
25th April 2014
Visitors to Aberdeen city centre could soon be forgiven for thinking alchemists have been at work on Union Street, where asphalt will soon apparently have been transmuted into Caithness slate.
The optical illusion being created on the south pedestrian area of Union Bridge will give the impression that hard-wearing asphalt has been replaced by Caithness slate.
The second of a three phase operation, which saw thin and frequently damaged concrete slabs on the pedestrian area replaced by asphalt in early autumn 2013, is being carried out by Aberdeen City Council,
The Caithness slate slabs, which are used elsewhere on Union Street, are too thick to use on Union Bridge due to the limited depth available between bridge deck and footpath.
Aberdeen City Council, in order to solve both problems, is trialling the use of a new operation called StreetPrint, which mimics the visual effect of the Caithness slabs in asphalt.
The imprinting process, which involves pressing a metal template into the asphalt pavement to replicate, in relief, the grout depressions common to the Caithness slabs, is now underway. Once it has been completed the imprinted asphalt pavement surface will painted in a colour similar to the existing Caithness slabs.
Councillor Marie Boulton, chair of the City Centre Regeneration Board, said: "This is a very interesting trial which I am confident will make a very noticeable difference to this section of Union Street.
"The old slabs were very frequently broken, were uneven and looked shabby, particularly compared to the Caithness slate slightly further down Union Street. We can't use Caithness slabs on the bridge for technical reasons, but this new StreetPrint technology provides us with an alternative option which will improve the look of Union Street. I look forward to seeing the finished product and the outcome of the trial."
The south pavement of the bridge has been closed during the imprinting works. The painting will be carried out when weather conditions are suitable.
Union Bridge Taken from the lower side of Union Terrace Gardens - Photographer Andrew Wood