Geotextile in Foundation Reinforcement

[rle3024]

I have determined three layers of geotextile beneath a drainage structure are necessary to help with bearing capacity and settlement. What is the best way to transition from the layers of geogrid with aggregate between them to the soil backfill surrounding the reinforcement? Should the aggregate be brought down on a slope or leave a vertical face between the geogrid/aggregate system and the backfill?

 

[dicksewerrat]

Geogrid and geotextile mean two different things to me. One is agrid with spaces between what will call 'fibers'so one gets interlock between layers and the other is a clothlike fabric.

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[rle3024]

Geogrid is what I meant.

 

[molerat2210]

rle,

Tensar has lots of resources for calculating piping ratios.

The best thing is dense graded aggregate. This will get you the desired interlock in the grid and hold back the soil. It's compacted so it makes the engineer feel better. The edges of the base improvement layer are always vertical.

You can use #57 stone or #2 stone if you want to keep the contractor from crying about compaction.

 

[rle3024]

Thanks, molerat2210. So, to ensure my understanding, acceptable compaction can be achieved with hand compaction/tampering of the backfill material in the triangular shaped space between the 2:1 excavation lines and the vertical face of the geogrid system?