That you think I'm talking about Boris, when I said I wasn't?
Where'd I say that?
That you brought up Boris's other ideas, as if they weren't mentioned already?
Brought up in brief comparisons to ideas which for example, were not included in your link, like Boris bikes - merely for the illustrative purpose that they point to an obvious attempt at legacy building
I don't think you read the link, and then certainly seemed not to have read "maybe there's something to be discussed with regard to the engineering? What pattern/variety of spans, and what heights?"...
Never mind. It seemed like it would be a good tech/engineering discussion of what a Channel Bridge could look like (with current/latest levels of engineering prowess and ixeas), but clearly there's no milage in that.
You all right m8 cos you're being unnecessarily salty for no reason, I posted links to theoretical UK-Ireland bridges and the actual Chinese Hong Kong-Macau bridge to lend some ideas on how people have tried to plan similar things, or achieved similar things. You misjudge my sincerity :<
More on topic: some things are immediately apparent about what such a bridge would have to look like, all of which centers around its size, cost and the problem of maritime impediment.
The Hong Kong-Macau bridge is under 23km long, the Straits of Dover are at their narrowest 33km in length. This would make a Channel bridge, very fucking big. Not just in length - in order to ensure maritime passage for shipping, of which for example a QE Carrier is 45M above the waterline, a cargo ship usually between 30-40M above the waterline, but the largest cruise ships and luxury passenger liners can get to 70M above the waterline, and some of the world's largest ships pass through making width an important concern too. This would mean the bridge would have to hold itself 75-80M above the waterline at the spring tide and close-set pillars would be out of the question, even if cost or ecology was not an issue.
This is useful information because then it helps us to conceptualize what a theoretical bridge would look like. As before: Very big. It would have to be done in multiple spans suspended between multiple towers. It would have to be study enough to survive collision with some of the largest ships in the world, and it would need to be both resilient in the face of the worst Atlantic weather, and have weather guards for drivers actually atop the bridge.
Using this handy thing we can roughly gauge that with a 1:6 optimal tower height to central span ratio, and with a 1km span per segment as per Bojo's proposal, each tower would optimally be under just under 170M high. Which if you factor in the depth of the straits at its deepest, the height of the tallest ships reasonably expected to pass through & the spring tide, should still allow the largest of ships through safely.
Notably past proposals in the 80s had planned bridges rise just under 70m above waterline, and was mooted for impeding nautical traffic, with smaller ships back then. It'll
also be a suspension bridge because that'd be the most cost effective for a bridge of this size. Of note, the pylons of such a bridge would be pretty fucking tall too, for example in the previous link bridges with spans of a kilometer have pylons with heights of 298m, with the lowest being 155m. This would be a big bridge, the biggest bridge
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