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Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
4.2
Methods based on Cone Penetration Test (CPT)
A method based on CPT is detailed in the report of the NCEER
and NCEER/NSF Workshops (Youd et al. 2001). This method
was critically reflected by Howie and Vaid (2000) and has been
actualized during the last decade; the last report was published
by Robertson and Cabal (2010).
CPT has in comparison to SPT advantages such as good
repeatability of the results which are represented as continued
profiles or a better identification of layered soils (Youd et al
2001, Robertson and Cabal 2010). However, the procedures
which were firstly developed for estimating potential of
liquefaction are based on SPT, which explains why those tests
are often used and that the data bases are more extended. This
difference tends to be reduced, as procedures based on CPT
were during the last decade subject of larger investigations
(Robertson and Cabal 2010).
4.3
Further corrections by the SPT and CPT methods
Influencing factors about the calculated value CRR
7,5
are the
inclination of the ground surface, the depth, particularly the
overburden pressure and the earthquake magnitude. The
correction factor K
σ
for a low sloping ground was reviewed and
discussed by Seed (2010), based on the monograph of Idriss and
Boulanger (2008). Those correction factors are not considered
in Eurocode 8.
Correction factors for the earthquake magnitude (Magnitude
Scaling Factor MSF) depend in the most cases of the Moment
Magnitude M
w
. In the Eurocode, the correction factor depends
on the Surface Wave Magnitude M
s
. Pertinence of Magnitude
type is discussed by Youd et al. (2001).
5 CONCLUSIONS
Procedures for estimation of liquefaction potential are still in
development, which results in an increasing number of
divergences between research reports and standards commonly
used. A more accurate study of the last reports on this theme is
therefore required to obtain a valid actualization of the
estimation of liquefaction potential in the Eurocode. Following
are some points which could be additionally considered or
further investigated in order to improve the actual European
standard:
•
Scope of available screening criteria for a preliminary
judgment about liquefaction susceptibility
•
Influence of Fines Content and consideration of Fine
Grained Soils
•
Explanations about the soil parameter S
•
Probabilistic SPT-Procedures
•
More details about CPT and eventually about tests
measuring shear wave velocity (Spectral Analysis of
Surface Waves SASW or Multichannel Analysis of
Surface Waves MASW)
•
Divergences between correction factors by assessing the
Cyclic Resistance Ratio.
6 REFERENCES
Cetin K. O., Seed R. B., Kiureghian A. D. Tokimatsu, K.,
Harder L. F., Kayen R. E., Moss R. E. S. 2004. “Standard
Penetration Test-based probabilistic and deterministic
assessment of seismic soil liquefaction potential”.
Journal
of Geotechnical and Geoenvironmental Engineering
130
(12), 1313 – 1340.
Day R.W. 2002.
Geotechnical Earthquake Engineering
. Mc
Graw-Hill, New York.
Eurocode 8: Design of structures for earthquake resistance –Part
5: Foundations, retaining structures and geotechnical
aspects. German version DIN EN 1998-5:2010.
Howie J. A. and Vaid Y. P. 2000. “Evaluating cyclic
liquefaction potential using the cone penetration test:
Discussion”.
Canadian Geotechnical Journal
37, 270–271.
Idriss I. M. and Boulanger R. W. 2008.
Monograph MNO-12:
Soil liquefaction during earthquakes
. EERI, Oakland,
California.
Idriss I. M. and Boulanger R. W. 2010.
SPT-based liquefaction
triggering procedures
. Department of Civil Construction
and Environmental Engineering, University of California at
Davis.
Kishida T., Boulanger R. W., Abrahamson N. A., Driller M. W.,
Wehling T. M. 2009. “Seismic response of levees in
Sacramento-San Joaquin Delta”.
Earthquake Spectra
25 (3),
557-582.
Prakash S. and Puri V. K. 2010. “Recent advances in
liquefaction of fine grained soils”, Fifth International
Conference on Recent Advances in Geotechnical
Earthquake Engineering and Soil Dynamics on May 24-29
2010, San Diego, California, Paper No 4.17a.
Prakash, S. and V.K. Puri. 2012. "Developments in geotechnical
earthquake engineering in recent years – 2012”, Invitation
Jai Krishna 100th Anniversary Volume, Oct-2012.
Robertson P. K. and Cabal K. L. 2010.
Guide to Cone
Penetration Testing for Geotechnical Engineering
. Gregg
Drilling & Testing Inc., California, 4th Edition.
Seed H. B. and Idriss A. M. 1971. “Simplified procedure for
evaluating soil liquefaction potential”.
Journal of the soil
mechanics and foundations division
97(9), 1249 – 1273.
Seed R. B., Cetin K. O., Moss R. E. S., Kammerer A. M., Wu
J., Pestana J. M., Riemer M. F., Sancio R. B., Bray J. D.,
Kayen R. E. and Faris A. 2003. “Recent advances in soil
liquefaction engineering: a unified and consistent
framework”, white paper for keynote presentation, 26th
annual ASCE Los Angeles spring seminar. University of
California, Berkeley.
Seed R. B. 2010.
Technical review and comments: 2008 EERI
Monograph “Soil liquefaction during earthquakes” (by I.
M. Idriss and R. W. Boulanger).
Report No. UCB/GT –
2010/01. University of California, Berkeley.
Youd T. L., Idriss I .M, Andrus R. D., Arango I., Castro G.,
Christian J. T, Dobry R., Finn W. D. L., Harder L. F. Jr,
Hynes M. E., Ishihara K., Koester J. P., Liao S. S. C.,
Marcuson W. F III, Martin G. R., Mitchell J. K., Moriwaki
Y., Power M. S., Robertson P. K., Seed R. B., Stokoe II K.
H. 2001. “Liquefaction resistance of soils: Summary report
from the 1996 NCEER and 1998 NCEER/NSF workshops
on evaluation of liquefaction resistance of soils.”
Journal of
Geotechnical and Geoenvironmental Engineering
127 (10),
817–833.
