I had put up a 1/4 wavelength 20m vertical with 1/8 wavelength
radials elevated at 7 feet, with rope guys... and the wind blew it
apart like so much tin foil!

It decided to blow it down so you could rebuild it with the proper
length radials... 1/8 radials won't work too well. Why would you
use those? They are fairly useless on an elevated ground plane.
The decoupling of the feedline will be poor, and probably lots
of rf in the shack. Needs 1/4 wave radials to work correctly.
As far as the wind, you need to build a little stouter... Normally, a
short 16 ft radiator should be easy to keep up, even with 60 mph
winds. Shouldn't fall down if it was guyed. My 40 m ground plane
was 32 ft tall, mounted at 36 ft. Nearly 70 ft tall at the top. Only
my mast was guyed. No guys were used on the radiator. I used
a telescoping metal mast which shrunk down to a very thin size
as it neared the top. Was quite flexible. In heavy storms, it would
nearly blow sideways, but it never hurt it, and it always popped
back up straight after the wind left. That particular antenna cost
nothing..Made from an old butchered up 5/8 wave CB antenna as
the base radiator, and then extended with extra tubing.
Was looking at your 2nd post, and notice the details. Not
exactly the recipe for a solid antenna...You would be better off
using an old butchered CB antenna, etc. The cushcraft AR-10
makes a good platform for verticals also. It's a 16-18 ft 1/2 wave
antenna for 10m. If you use only the radiator, and redesign the
feed, thats a decent quicky 20m 1/4 wave vertical. The old heavy duty
5/8 CB antennas are good to use also. They have heavy duty
bases that are often reinforced. Thats what I use for my tall 40m
antenna, and never had a problem, but I did strengthen by adding
extra tubing , inside the tubing. IE: double wall... Copper is pretty
soft, and shouldn't be used for anything that needs real strength.
MK