Engineering Saves the Great Hall
28. May 2019 |
One of the major challenges involved in restoring Nyborg Castle is how to support the ceiling above the Great Hall in the Castle. Anyone who has entered the beautiful hall, built in the 16th century, will have noticed how the heavy, 500-year-old ceiling beams are buckling in the middle. This is due to the fact that the timber floors above were used for storing grain. For a period, the beams were also supported by temporary girders.
The majestic beams in the Great Hall need to be preserved, even though, over the years, many of them have been exposed to wet rot and dry rot and no longer have the bearing capacity they once had. Consequently they need support. So, in July and August 2018, new rafters were inserted into the roof structure, which can bear a number of long, solid, round steel tie rods, which go 8-10 metres down through the fourth and third layers of timber and are fastened to steel beams, which are then inserted longitudinally with the royal wing in the cavity above the buckling ceiling beams in the Great Hall. The ceiling beams are attached to the steel beams, thereby receiving the necessary support. In fact, according to the calculations of the engineering firm, it would now be possible to accommodate 30 horses in the small chambers above the Great Hall.
The chosen method for supporting the floor deck over the Great Hall was a continuation of the method used in the 1960s. At that time they were also aware of the challenge posed by the bearing capacity of the ceiling beams. Then they inserted one steel beam suspended in three tie rods. It turned out not to be enough. The new structure extends the steel beam from the 1960s to almost 25 metres, and another was inserted in parallel. In future, the load-bearing steel beams will be suspended in a total of 8 tie rods. Although the tie rods go up through the third timber floor, they will not be visible here. They have been directed through the walls that separate the many small chambers in the timber floors.
As a result of the new support, carpenters and bricklayers can continue their work of preserving the splendid 16th century beams by removing the parts that have been destroyed by wet rot and dry rot.