Silbury Hill 180
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Silbury Hill

When Silbury is tunnelled

VenerableBottyBurp V
VenerableBottyBurp Jun 1, 2005 20:26:34
Replying to Jo-anne

There is no known burial Jo-anne, and there have been one top to bottom shaft 1776-7 (this started the problem), then a tunnel in 1849, and they cut side galleys in and around the centre that in plan view looks like an asphix key shape, and another tunnel was cut in 1968 joining the older tunnel.

The problem is that it wasn't known that the shaft was never properly backfilled because no record was made at the time and EH and their state ancestors have never kept any records in over 120 years, so a pattern of material dropping down the shaft wasn't noticed and was continually topped up by maintenance crews who throught the damage caused by rabbits. This material in the shaft eventually collapsed because the 1968 tunnel was refilled by spoil being blown back in (a standard mining technique at the time) and this left voids as it wasn't truly compacted. Roof falls above these voids finally combined with rain from above and material collapsed down the shaft in 2000. A further major collapse occurred because EH ignored advice to use a tarpaulin cover and went for a metal cover suspended on scaffold poles, this collected water and as they had fitted no means of guttering it deposited the water down the shaft, the metal cover inevitably attracted ice loading that made the structure multiply its own weight by Ks, thus it collapsed into the hole sending more precious archaeology into oblivion.

This is only part of the story of course.

Sorry, I have to go for my tea so haven't re-read this.

VBB

J Jo-anne
Jo-anne Jun 1, 2005 21:53:10
Replying to VenerableBottyBurp

Thanks VBB,

The way you just explained it made it very clear.
So the picture is this? If nothings done soon it will be washed out a bit like a inward landslide, but then in a more serious manner as water and ice are involved and it is not surrounded by supporting earthhills, the process if not taken proper measures will proceed rapid till it's flattened, ... collapsed.

Except for dating material and a cross section of the earth, that can be done with relative ease and nowhere near as distructive as tunnels. There is no need for further investigation to the hill.
And as there is nothing to see on the inside a glass tunnel would be of totally no interest to anyone.

Again thank you for your explanation.

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