The sculpture would have a flat roof and slightly inclined walls. The excavated surfaces are to be formed with flat, high quality finishes, with no visible support. This results in a unique engineering challenge, whose construction would push the limits of cavern design and construction.
In order to realise the artist鈥檚 concept, the design comprises the formation of a series of reinforced rock arches within the rock mass above the cavern roof and pre-support of the cavern roof with rock anchors fixed to the arches. The arches would be created with rock anchors radiating around the tunnels which would also provide access for long term maintenance, monitoring instrumentation and drainage. The reinforced rock arch tunnels would be formed from the light shafts prior to the main cavern excavation. The rock anchors supporting the cavern roof would be installed in predrilled holes as they are exposed during cavern excavation.
The cavern would be constructed within the trachyte rock mass making up the majority of the mountain and would also encounter highly persistent master joints and basalt dykes. Specific local treatment and support is expected to be required to stabilise these features. There are also durability issues associated with the particular micro-structure and porosity characteristics of the predominant trachyte rock itself that have been addressed to meet the long-term design requirements.
This paper describes the phased investigation and development of the design concept. The project is currently under consideration by the Canary Islands Government.