Frictional connection - Geogrid and Concrete Retaining Wall 1

[TKMOT]

I am in the process of designing a geogrid reinforced concrete Lock-Block retaining wall (some 5 m in height). The geogrid will be attached to the wall through a frictional connection between each successive layer of blocks. I was wondering if it was a wise choice to also specify a thin layer of sand between the blocks (nominal 25 mm/1 inch)and the grid to provide a more uniform frictional connection. Or, does the weight of overlying blocks and the concrete surface on the grid generally provide an adequate frictional connection.

 

[JasonG]

Sand is not necessary. I suggest contacting the manufacturer for pullout strengths.