Geotextile use for sewer trenches 1

[13sam13]

I have a new challenge and I wonder if any body can help.

I dont know how much effective a geotextile implementation for sewer trenches design and the design considerations to prevent future settling problem. the following might give an idea of the situation

1- The trench has a fluctuating Water table.

2- The soil surrounding the trench is not good
(silt ,clay.fine sand,etc..)

3- The trench is located in main Roads with heavy traffic.

4- The pipe is not deeper than 5 metres

5- The Trench is wide (pipes dia. 400mm or larger)


thank you for your help.

 

[dirtsqueezer]

I'm not sure what the fellow posters would say, but if you're backfilling bad material in a 5 meter trench, geotextile fabric might not be that much of a help. From my experience you need weight from the surrounding soil to hold tension on your fabric, and there would be none of that in a trench. See what everybody else says. If you do end up using it, you would probably want to go with something like mirafi lining the trench including the walls about two feet below grade after having compacted the lower material as best as possible. If you have water problems while replacing the material, you could go with railroad ballast (2-4"), that holds weight in the presence of water, at least to the top of the water table. Good luck. I don't look forward to jobs like these.

 

[fattdad]

Use flowable fill. Not sure geotextile is needed.

f-d

¡papá gordo ain’t no madre flaca!

 

[civilperson]

No advantage in using geotextile unless you are importing the backfill/bedding and it is crushed rock/gravel with a lack of fines.