(Tool deployed : Multi Purpose cylinders)
At the beginning of the previous century a new castle was built on the foundations of a seventeenth century
fortress. This foundation turned out to be too weak to support the new and massive building. The castle started subsiding in the mid nineties and the only way to save it, was to reinforce its foundation. However, sinking piles into the ground for extra support was not an option : There simply was not enough space and it would disturb the ground too much, resulting in more damage. Therefore another approach was needed and it was decided to fit the castle’s foundation with supporting poles.
The operating procedure
(1) Steel tubes were drilled into the ground on both sides of the castle walls. At the same time a mixture of cement and water was pumped in. Thus, the soil was not being removed, but blended with the mixture. When the tubes were drilled in deep enough, (2) a hole was drilled in the wall, (3) and a steel H-profile was positioned through it, resting on the tubes. On top of this a load spreading plate was fixed. (4) By means of hydraulic cylinders the H-beam was put under pressure. (5) Then, the resulting gap between the tubes and the beam was filled up with steel plates. (5 + 6) The surrounding floor and any gaps in the walls were filled up with concrete.
A fully supported, stable and safe structure. Once this major project was finished, the wall and surrounding area showed no indication of the work that had been undertaken.