|| Left Valley Side | Right Valley Side | Pole Bridge | Magic Rock ||
|The construction of all
structures in the
Boulders had to be adapted
to the micro climate of the valley. During many months of the year, the valley
floor is wet or moist under quite warm temperatures. Leaves will drift in the wind
and fall into the structures so that they are often constantly kept wet. As well
as this, moss will grow on the different parts of the structures, mainly on the parts near
Therefore great care has been given to these conditions and the building materials have been selected accordingly.
All materials had to be transported a long stretch through dense bush, which is not so easy if the planks are 7 m long. Special tracks had to be found to manoeuvre them around the many trees and bushes.
|All bridges follow the
same design. Only the height of the main beams is altered according to span.
If the abatement is on top of a rock or boulder, Bowmac stainless steel brackets
were bonded into the rocks with epoxy resin.
Left: Principal design for footbridges. Some details had to be adapted due to local circumstances.
The platform was designed to make sure it is totally safe. All loads are transferred on timber to timber contacts and the bolts are only to keep the parts in place. They do not actually transfer any loads, except horizontal pressure from the hand rails.
Right: Design of the platform, view from the valley side.
All timber is Pinus Radiata first grade and H4, H5 treated. (H4, H5 treatment prevents the deterioration of timber trough bacteria, borers or funguses.) It is certainly unaffected for 50 years. Timber thickness varies between 50 and 100 mm, but 50 mm planks have been used predominantly for beams, floors and handrails, whereas posts are in heavier sizes.
The foundations of bridge beams are prepared. The rocks are shaped so that the fittings can be glued with epoxy resin into the boulder. The level of the fittings has to be lowered so there is no extra step needed to go onto the bridge. The rock, being basalt, is very hard to drill.
To enable easier communication, we gave names to all bridges and stairs. The names chosen were names of people we love and cherish.
This ads a bit of flavour to this unique Tourism Attraction in Northland of New Zealand.