The rooster likes to get his flock going early on these late spring mornings, so I often am awake before five. Early morning, with the first grey light is a good time for worrying and, occasionally, solving.
The current preoccupation is weight. How much are these concrete panels in the table going to weigh, and is the structure strong enough to support them? A lot of fretful musing has gone into this, but lacking hard data, has not really come to much except to reflect varying moods of mild hopefulness or vague pessimism.
So yesterday it was time to put some numbers into the mix. The table top is 10' x 5', or 120" x 60". There is a 2" thick frame all round, and one long (120") divider and two short 60" dividers between the various panels, This gives a total effective panel size of 112" x 54". If the panel is 2" thick, we'll have a total of 12,096 cubic inches, or 7 cubic feet of concrete. According to various sources, concrete weighs about 140 lbs./cu. ft. – which gives a total of just under 1000 lbs.
Rough sketch:
There's some math somewhere that could give me the theoretical deflection of the three combined longitudinal beams over the 8' span with the 1000 lb. weight of the panels distributed evenly over the 10x5 surface. Where it is, I've no idea. As usual, I should have paid more attention to my sixth-form physics master. ( Was his name "Welsh"? - Chiswick County Grammar School for Boys, 1961).
It looks OK to me. On the other hand, I'm glad that whoever designs roads, bridges, ferries, cars and aeroplanes DID pay attention, and didn't think that skiving off to the library and reading "As You Like It" was somehow a much worthier use of time.
I'll give it some more thought tomorrow morning.