Environmental Engineering Reference
In-Depth Information
1.25
Indicates poorly compacted
upstream rockfill
Djatilihur
1
Eppalock
Svartevann (left abut.)
Gepatsch
Upper Dam
0.75
Bellfield
0.5
Maroon
Windemere
0.25
0
0
25
50
75
100
125
150
175
200
Embankment Height (m)
Clayey core, fluctuating reservoir
Clayey core, steady or slow reservoir
SC/GC core, fluctuating reservoir
SC/GC core, steady or slow reservoir
SM/GM core, fluctuating reservoir
SM/GM core, steady or slow reservoir
Figure 6.42. Long-term post construction crest settlement rate for zoned earthfill and earth-rockfill
embankments of thin to thick core widths (Hunter, 2003; Hunter and Fell, 2003d).
Table 6.8. Embankment crest region, typical range of post construction settlement and long-term settlement
rate (Hunter, 2003; Hunter and Fell, 2003d).
Long-term settlement
Crest settlement (%) *
1,
*
2
rate*
1,
*
3
Core properties
Core
Moisture
20 to
Steady/slow
Fluctuating
Classification
width
content
3 years
10 years
25 years
reservoir
reservoir
CL/CH
Thin to
dry
0.05 to 0.55
0.10 to 0.65
0.20 to 0.95
0.04 to 0.50
0.09 to 0.57
medium
wet
0.04 to 0.75
0.08 to 0.95
0.20 to 1.10
(most
0.26)
all
0.02 to 0.75
0.10 to 1.0
0.5 to 1.0
Thick
(most
dry)
SC/GC
Thin to
dry
0.10 to 0.25
0.10 to 0.40
0.5
0 to 0.26
0.06 to 0.37
medium
wet
0.15 to 0.80
0.20 to 1.10
1.1
all
0.05 to 0.20
0.10 to 0.35
0.10 to 0.45
Thick
(most
dry)
SM/GM
Thin to
all
0.06 to 0.30
0.10 to 0.65
0.5 to 0.7
0.10
0.03 to 0.21
thick
Very broad earthfill cores -
0.0 to 0.60
0.0 to 0.80
0.05 to 0.76
0.08 & 0.44
0.07 to 0.70
most CL and dry placed
(most
0.35)
Notes: *
1
Excludes possible outliers.
*
2
Crest settlement as a percentage of the embankment height.
*
3
Long-term settlement rate in units of % settlement per log cycle of time (settlement as a percentage
of dam height).
observed for dry placed and/or weathered rockfills, where settlements due to collapse
compression are likely to be significant;
- Much lower settlements, generally less than 0.5 to 0.7% at ten years after construction, are
observed for well and reasonably to well compacted rockfills, and compacted earthfills;
-Very low settlements (less than 0.25% at 10 years) are observed for embankments with
gravel shoulders.
