Topbond were given the task of reconstructing the rollercoaster structure that was Grade II listed in 2002 and Grade II* listed in 2011.
It was not without its challenges. Constructing ‘like for like’ to maintain its Grade II listing whilst complying with current design standards naturally resulted in conflicting objective. Working closely with English Heritage during the project we were able to overcome those challenges.
The 14m high timber construction is not fixed to its new concrete foundations. Instead, it sits on neoprene pads which absorb shock loadings - gravity holds the structure in place. In all, there is 930m of track around the ride. 300 tons of Spruce replaces the existing softwood used, a very durable timber, which was sourced from Germany. The plantation was chosen for its fairly constant climate. The timber was sawn, then graded to C24 requirements before being shipped to the UK where it was double vacuum treated and checked for adequate penetration of the preserve. A dynamic analysis was undertaken to provide the worse case loadings at each trestle location around the ride. This included loadings on both horizontal and vertical curves together with canting around the bends. This enabled Topbond to structurally analyse every timber component on the job. The geometry of the ride means that every support trestle is different, so each one had to be detailed separately.