1830
Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
Table 6. Results of stability analysis performed according to Eurocode 7
at the Antoniny site.
5
CONCLUSIONS
The example of the determination of derived, mean,
characteristic and design values of undrained shear strength of
organic soils obtained from field vane tests for stage-
constructed embankment at the Antoniny site was presented.
Safety factor F
Stage Mean and characteristic values
of undrained shear strength
DA1(C1)
DA1(C2),
DA3
1.82
1.46
- 0.5SD
1.71
1.39
1
- SD
1.60
1.28
1.41
1.12
- 0.5SD
1.33
1.07
3
- SD
1.26
1.01
0.75
0.60
- 0.5SD
0.71
0.57
Failure
test
- SD
0.67
0.54
Performed stability analysis shows, that Design Approach
DA1(C1) for stability assessment of embankment on organic
soils during construction using the characteristic values of
undrained shear strength evaluated based on Schneider’s
proposal from mean values and standard deviation of undrained
shear strength derived from field vane test is recommended.
Calculation results show that after construction the first
stage of embankment with a height of 1.2 m exists a large
reserve of safety. In connection with it, for the embankment
with a height of 1.7 m additional calculations were carried out
using mean values of undrained shear strength. Then, safety
factor was equal to 1.16 while
= 3.4. Using logistic type of
distribution which better characterized distribution of shear
strength the safety factor was close to one and
= 2.2.
Performed calculations shows that the first stage of
embankment could be constructed higher.
Experience indicates that Design Approaches DA1(C2) and
DA3 introduce too much safety for the embankment on organic
soils during construction. In this case the mean values of
undrained shear strength evaluated based on corrected values
from field vane tests, as characteristic values are recommended.
6
ACKNOWLEDGEMENTS
This research was supported by Grant N N506 218039 from the
National Science Centre. Cracow, Poland.
7
REFERENCES
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soils based on the design values of undrained shear strength
evaluated using partial factor
M
= 1.25, characteristic values of
τ
fu
from Schneider’s recommendation, mean values of τ
fu
determined from undrained shear strength derived after
correction of measured values of τ
fv
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for embankment during construction. The calculation results
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