3 ms·
This is footprint. It’s unclear whether the full footprint was sunk to your depth. Regardless, that’s much closer than I anticipated it would be, which is pleas
by abduhl 3y ago
This is footprint. It’s unclear whether the full footprint was sunk to your depth. Regardless, that’s much closer than I anticipated it would be, which is pleasantly surprising.
We can refine the estimate as well: surface soils probably make up half of the depth (25 ft) and granite rock the other half (30 ft). Blended unit weight would then be ~150 pcf. About 327,000 short ton.
- ghc 3y agoI based my estimate on photos of the foundation work like: https://keithyorkcity.files.wordpress.com/2013/02/1930-march-31-looking-se.jpg https://keithyorkcity.files.wordpress.com/2013/02/1930-march... I couldn't find actual blueprints.
- SoftTalker 3y agoI'm not sure that surface soil is that deep. I seem to recall that in parts of central park the granite is exposed.
- saalweachter 3y agoYeah, NY throughout the Hudson Valley has shallow soil. The glaciers swept everything clean 21k years ago, dropped it all to form Long Island, and barely any of it has come back. (Looking it up, the first result says that soil for at a rate of about 0.5-1 inch/millennia, which sounds about right for how much has re-accumulated, on average.)
- 082349872349872 3y agoAn anecdote that I've heard is that the NYC skyline and underlying geologic map correlate pretty closely; the skyscrapers were apparently built where the bedrock was conveniently close to the surface.