smoothops10
Member
- Location
- FL
- Occupation
- EE
I've seen several utility and campus style standard specifications prohibit vertically stacking ducts in a direct burial duct bank. Sometimes an exception is given for communications ducts where they are allowed to be on the top row in a 2x2. I am trying to understand the reasoning behind the prohibition of vertically stacked ducts in direct burial install. I realize the weight of a set of 500kCMIL may be 6+ lbs/ft and maybe has something to do with not wanting the weight of the heavy duct on top of another duct below it whereas a comms duct would weigh little and be subject to much lower pulling forces and minimal weight in lbs/ft but really what does it matter if the first row of ducts is properly compacted? Any thoughts appreciated - thanks.