﻿ How much weight is required to maintain submerged a 290 ft long section of one of the tunnels in the
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### Question

How much weight is required to maintain submerged a 290 ft long section of one of the tunnels in

the Chesapeake Bay Bridge-Tunnel? For this, you need the actual cross sectional area of the tunnel

that you are going to assume as cylindrical. Details of it can be found at:

http://www.ien.com/ienblog.aspx?id=139703

Additional info can also be found here:

http://www.cbbt.com/facts.html

How much backfill weigh you need to put on top of the tunnel? For this, assume the tunnel is made

out of concrete only.

Make any reasonable approximation you need

### Solution

xxxxxx: The xxxxxxxx xxxxxxx xxxxxxxxxxxxx site xxxxxxxxxxx are xx xxxx.xxx x and xxx 032.053 x (xxxxxx x). This xxxx is x xxxxxxxxxy xxxx-xxxxxxxx area xxxxxxx between xxxxx xxxxxx (xxxx foot xxxxx to xxx xx, xxxxxxxx Shoal xx the xx xxx xxxxxx Ground xxxxx to xxx x) xx water xxxx an xxxxxxxxxxx xxxxx xx 17-20 xxxx (ft) xx xxxx xxx tide (xxx). It xx xxxxxxx x.xx NM xx and xxxxxxx xx xxx Chesapeake xxy Bridge-Tunnel (xxxx) xxx x.x NM xx of xxxxxxxxxx xxxxxx. xxxxxy nautical xxxxxxxx include: xxx xxxxx xxxxxxx (1 xx NE) xxx xxx xxxx Shipping xxxxxxx (3.2 xx xx). xxx bottom xxxxxxxxxx of xxxx xxxx xxx shown xx consist xx xxxx xxx shell xxxxxxxxx to xxxx xxxxxx xxx currents xx the xxxx xxxxxxx x knots xxx can xxxxxxxx xx xxxx 3 xxxxx in xxxxxx xxxxx. xxx proposed xxxx is xxxxxx xxxx xxxxxxx and xxxxx waters xxx xxxxxxxxxxxxy x.x nm xxxxxx the xxxxxxx xxxxxxxxxxx xxxx and xxx Boundary xxxx. x xxxxxx zone xx 3 xx xxx xxxxx and x nm xxx xxxxxx xxxxx is xxxxxxxxx by xxx xxxxxxxx xxxx. It xxxx not xxx xx xxy marked xxxxxxxx, but xxxx xxx xx a xxxxxxxxx Navigation xxxx xxxxx xx CFR xxx.xxx. The xxx xxxxxx xxxx vessel xxxxxxx than xx xx xxxxxx are xxxxxxxxxx from xxxxxxxxx, xxx xxxxx the x/x Vantages xxxxx xxxxxx xx less xxxx 65ft xx xxxxxx xx able xx legally xxxxxx, xx xx this xxxx, hold xxxxxxx xy xxxxx of xxxxxxxxx on xxxxx. xxxx xxxxxxx in xxxx summer xxx xxxx xx compromised xxxxxy by xxx xxxxxx xx a xxxxxxxx cyclone, xxxxxxxxxxxy xxxx xxx-xxxxxx through xxx first xxxx xx xxxxxxx. A xxxxxxxxx affects xxx xxxxxxxxxx xxy about xxxx every xx yxxxx xx the xxxxxxx. Thunderstorms xxxxx xx x to x days xxx xxxxx xx September xxx October xxx xxx xxxxxxy associated xxxx increasingly xxxxxxxx xxx xxxxxxxx cold xxxxxx. Fog xxxxxxx xxxx xx a xxxxxxx, particularly xxxxx xx xxxxxxxxx. This xx a xxxxxxx xxx xxxx forms xx 1 xx x xxyx per xxxxx during xxxxxxxxx xxx xxxxxxx over xxx upper xxxxxxx xx xxx bay; xx usually xxxxx xy xxxx. In xxxx summer xxx xxxxxx xxxxxxxxxxx may xx sighted. xxxxx xxx xxxxx-xxxxx and xxxx severe xxxx xxxxx xxxxxxxxxx with xxxxxxxxxxxxx; maximum xxxxx xxxxx xx about xx knots. xxxy xxx xxxxxx by xxxxxx air xxxxxxxxxx x xxxy of xxxx moist xxx xx xxxxxxxxxxx with x cloud xxxxx xx xxxx the xxy; they xxxxxxy xxxxx xx fair xxxxxxx. This xxxxxxy xxxxxxxx xxxxxxxxxxxxxx information xxxxxxxxxx to xxx xxxxxx xxxxxxxxxx Bay. xxxx November xxxxxxx xxxxx xxxxxxxxxx Bay, xxxxxxxxxxxy the xxxxxxxx xxxxxxx xx rough xxxxxxx. Storms xxxxxx xx xxx Atlantic xxxxx generate xxxxx xxx xx the xxxxxxxxx quadrant xxxxx xx xxxxx centers; xxxxxx often xxxxx xx xx 50 xxxxx. Several xxyx xx xxxxxx and xxxxy northwest xxxxx xxy xxxxxx. Strong xxxx fronts xxxx xxx xxxx can xxxxxxxx 25 xx xx xxxx gusts xxxx open xxxxx. xxxxx xxxxxxxxxx with xxxxxx winds xxx xx xxxxx and xxx chop xxxxxxxx xxxx xxxxx winds xxxxxx strong xxxxx xxxxxxxx. xxxxxxxxxxx of xx knots xx xxxx, xxxx a xxxx fetch xx xxx xxy, can xxxxxy build x xx xx foot xxxx in xxx xxxxxxx xxxxxxx and x- to x-xxxx (x.x xx 2.1 x) seas xx xxx xxxxx. Seas xx 8 xxxx (x.x x) or xxxx occur xxxxx x xx 4 xxxxxxx of xxx xxxx xxxx fall xxxxxxx early xxxxxx, xx xxx bay. xxxxx can xxxxx xxxx xxxxxxxxx through xxxxx