I am involved a project dealing with slope stabilization.
The height of slope is about 106 ft, the angle is about 36. The upper 65 ft thick layer is primary composed of SP, and the lower layer is CL-ML. The friction angle of SP and CL-ML is 33, 30 respectively, allmost cohesionless for both. It's kind of strange it can stand there for many years, and recently some surface failures occured. Two water tanks is very near the toe of the slope.
My question is:
1. Is it possible to use geotextile/tensar geogrid to reinforce it?
2. Can soil nailing system be applied there? If so, can you recommend some reading material?
3. What's the best choice for this case?
Any suggestion is highly appreciated.( I am new in this area with little experience)