Does anyone have any experience with using drainage system comprising of expanded polystyrene (EPS) aggregates and a 4-inch perforated polyethylene pipe that are tightly packed into 10- or 12-inch diameter tubes of polyethelene netting in retaining wall applications?
The contractor working on the project is proposing to replace the approved drainage detail (a 4-inch perf pipe encapsulated in six inches of 1-1/2" crushed rock then wrapped with filter fabric) with this innovative system. Research on the web seems to indicate such system is typically used in shallow trenches with one to two feet of cover. The walls on the project are 8' tall with a 2H:1V backslope. My concern is the EPS aggregates along the soil-aggregate interface would be compressed so much that any water flow into the drain pipe will be impeded.
Any thoughts or advice?
Thank you.
The contractor working on the project is proposing to replace the approved drainage detail (a 4-inch perf pipe encapsulated in six inches of 1-1/2" crushed rock then wrapped with filter fabric) with this innovative system. Research on the web seems to indicate such system is typically used in shallow trenches with one to two feet of cover. The walls on the project are 8' tall with a 2H:1V backslope. My concern is the EPS aggregates along the soil-aggregate interface would be compressed so much that any water flow into the drain pipe will be impeded.
Any thoughts or advice?
Thank you.