Case studies
Medieval castle stabilised
The problem
Listed by English Heritage in its Register of Buildings at Risk, the tower of Scaleby Castle in Cumbria – built in 1307 – had begun to rotate away from the main structure of the adjacent nineteenth-century house.
The solution
"We wanted a solution which would not involve digging out beneath the walls since this would clearly be dangerous and could possibly speed the demise of the building altogether," said Charles Blackett-Ord, of Blackett-Ord Consulting Engineers, specialists in the repair of historic buildings.
"Conventional underpinning did not appear to be appropriate; Uretek Deep Injectioin technology was selected because, uniquely, it could be carried out without excavation of the foundations."
In just two days on site, Uretek operatives provided successful ground stabilisation for the tower. Having drilled a series of strategically placed small diameter holes two to three metres into the sub-strata directly beneath the castle walls from both the inside and outside, technicians injected fast-acting specialised resin which hardens immediately to a compressive strength similar to a concrete mix, but with only 10% of the weight.
Movement of the tower walls was carefully monitored by laser to ensure the correct quantities of resin were injected at each point to avoid over-correction.
The stabilisation project was part-funded by English Heritage.
