NCHRP 15-13 [Completed]
Long-Term Performance of Geosynthetics in Drainage Applications
| Project Data
|| $455,240 |
||Geosynthetic Research Institute of Drexel University|
||Dr. Robert M. Koerner|
Geosynthetics are used in several types of drainage applications and are the key to the performance of these systems. Applications include, but are not limited to, pavement edge drains, underdrains, slope drains, drainage behind retaining walls, french drains, and interceptor drains. Subsurface drainage is considered to be important for extending the life of pavements, slopes, and retaining walls. In order for these drainage systems to perform as intended, they need to be properly designed and constructed.
As a result of this project, a large database on field-exhumed geosynthetic drainage systems has been developed. Ninety-one sites (three categories: performing poorly, performing well, and uncertain) solicited from all 50 states have been thoroughly evaluated, and the performance of the applications has been compared with design criteria and construction techniques. These evaluations showed that the existing design methodology is acceptable for granular soils but that the criteria for fine-grained soils may need to be evaluated on a site-specific basis. Also, specific recommendations have been made in regard to construction practices associated with prefabricated-geocomposite-edge drains.
The final report for the project was published as NCHRP Report 367.