VAD & BigH: minimization of movement is definitely what we are going for. Because slope movements aren't endangering the dam they are viewed mainly as a nuisance, so extreme measures aren't warranted - no retaining structure, and probably no grout curtain. I was leaning towards drainage of...
VAD: I am intrigued by your suggestion of horizontal drains. My recollections from university suggested that horizontal drains would not be effective in draining a low-permeability material like the clay/shale I am dealing with, particularly because there is not well defined aquifer in the...
Hi, I am brainstorming for ideas to stabilize an overthrust developing on a dam abutment slope. It is a cut slope (8H:1V) in a clay/shale material, naturally given to slumping. The slope was constructed in the early '60s and is vegetated with local weeds and grasses.
Slope indicators in the...
I am looking for some information on Halcrow Buckets. I monitoring groundwater levels in an unstable slope (slope is undergoing slow downslope creep). I would like to get maximum water level readings but the standpipes are currently read manually once a month in the summer/fall and once a week...
...as to instrumentation, there are several SIs in the movement area - movements are around 5 to 12 mm a year (although more significant movements occur during years with high snowmelt/runoff). Piezometers were installed in November 2001: 13 standpipes (ID = 6" if I remember correctly) and...
Ok. More info. needed, not a problem. The slope is a dam embankment slope constructed circa 1960. A minor overthrust was detected in the slope in 1994 and associated upland cracking in 1995. The cracking was sealed and clay capped and has not reappeared. The current deformations appear to...
I am looking for information re: subsurface drainage of low-permeability materials. An overthrust has developed on a cut slope (7H:1V) of glacial overburden over clay/shale. I am investigating subsurface drainage for slope stabilization. Can anyone suggest any good...