Arkaroola Remote Observatory - South Australia
Construction Trip #1 - September 2011
The purpose of this trip was to level and prepare the ground to pour cement footings in order to accommodate our domes. To do this, we needed to calculate the volume of cement required, purchase and ship the lot up to Arkaroola. We also needed to prepare the concrete forms ahead of time and fabricate the steel plates and posts for the solar array and satellite. The pallet of ready-mix cement ended up cheaper than the shipping! We rented a flatbed ute and loaded it with tools, posts, footings etc. and headed up for an intense weekend of manual labour. We carved up the areas for the domes, levelled the ground, positioned the forms, mixed and poured the cement.
It is essential that the telescope pier is mechanically isolated from the rest of the observatory building as much as possible. This is to minimize the coupling of vibrations into the telescope from people moving about in the dome and more importantly in a remote setup, from wind impinging on the building itself.
Therefore we needed three pours per dome. We poured the octagonal pier footing first, then the outer octagon dome footing. Once these had set we filled in the gap with some crushed stone and poured a thin layer over the stone. The pier footing is isolated from the floor by a foam wrap. We also poured the footings for the solar panel posts and cut a trench between the domes for conduit.
Me measuring the pier offset
Pier and dome footings poured
Pier and dome footing dry and gap filled with crushed stone
State of observatory site at end of construction trip #1