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What does this mean in civil utilities drawings 1

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rb192

Structural
Dec 9, 2018
6
Hello all,

I have these civil drawings I need to work with and I'm not sure what the notation "4W-6"" meant. I tried to look up online at other places but got no information. Please let me
Screenshot_20240807_211417_Samsung_Notes_szjuev.jpg
know if you need more info or full set of drawings to help.

Thanks in advance!
 
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Pretty sure it's 4 wide then the size of the duct, but could easily be 4 way, so often a 2 x 2

8W is probably 4 x 2 high

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
Ask the site civil engineer, it's their notation.
 
It could be the number of wires in the duct and its diameter.
 
@coloeng is right, just got a confirmation from the civil eng
 
Then they shouldn't have called it a "duct bank".

Why not just call it a duct in that case??

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
LittleInch A underground duct would just be a buried conduit capable of containing multiple conductors. A duct bank would indicate a reenforced concrete encased conduit, typically with structural elements. Having a duct bank with only one conduit in it, is not uncommon. Thats said, I have never been a fan of the practice in an industrial setting due to how little extra cost is involved with install a bank with let's say 4 conduits (1 in service, 3 spare) instead of just 1 considering future expansion, redundancy and reliability but I've seen it done regularly in the commercial space. I am not too sure I agree with the way it was called out as conductor number and conduit size only, since I like to see at least a positive quantity confirmed such as [(3)W - (1)6"]. But since many underground drawings contain both civil and electrical elements it may not follow best practice electrical drafting wise.
 
In my part of the world, a duct bank is multiple ducts in the same duct run as noted by Heaviside1925 but not necessarily concrete encased. Concrete encasement (and reinforcement if concrete encased) is optional, depending on applied loading, duct strength and duct bank cover. We tend to require >=50% unused ducts in a duct bank to allow for future expansion. Also useful if a a duct gets too ovalised to allow a mandrel to pass.
 
4 high x 4 wide, 6" diameter conduits
OOOO
OOOO
OOOO
OOOO

1 high x 8 wide
OOOOOOOO

They could be HDPE these days.



--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."
 
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