1570
Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
compared to the simple shear test results. However, Liu’s
curves are steeper at
N
higher than 15. Considering that the
stress path imposed by a simple shear test better represents
actual soil response under vertically propagating shear waves, it
is recommended that the curves of Liu be used in the design if
N
M=7.5
= 15. For other values of
N
M=7.5
, the adjusted curves
proposed by Liu et al. (2001) can be used.
Finn W.D.L. and Bhatia S. 1982. Prediction of seismic porewater
pressures. 10th ICSMFE. Stockholm, 6.
Ivsic T. 2006. A model for presentation of seismic pore water
pressures.
Soil Dynamics and Earthquake Engineering
26 (2-4),
191-199.
Koester J.P. 1994. The influence of fines type and content on cyclic
strength. In: S. Prakash, and P. Dakoulas, Eds.
Ground Failures
Under Seismic Conditions, Geotech
: ASCE,
Kramer S.L. 1996. Geotechnical earthquake engineering. Prentice Hall,
Upper Saddle River, N.J.
Lee K.L. and Albaisa A. 1974. Earthquake induced settlements in
saturated sands.
Journal of the Geotechnical Engineering Division
100 (4), 10.
Liu A.H. 2001.
Equivalent number of uniform stress cycles for soil
liquefaction analysis
. University of California, Los Angeles,
Liu A.H., Stewart J.P., Abrahamson N.A. and Moriwaki Y. 2001.
Equivalent number of uniform stress cycles for soil liquefaction
anlaysis.
Journal of geotechnical and geoenvironmental engineering
127 (12), 1017-1026.
Figure 5. Comparison of normalized
CSR – N
curves shown in Figure 1
and Figure 2 and range of curves from Liu (2001).
Park I.J., Shin Y.S., Choi J.S. and Kim S.I. 1999. A study on the
conventional liquefaction analysis and application to Korean
liquefaction hazard zones. KGS Spring '99 National Conference.
Seoul, Korea, 431-438.
Polito C.P., Green R.A. and Lee J. 2008. Pore pressure generation
models for sands and silty soils subjected to cyclic loading.
Journal
of geotechnical and geoenvironmental engineering
134, 1490.
5 CONCLUSIONS
This paper presented a model for predicting the pore
pressure build-up under seismic loading. The model uses the
concept of damage parameter to transform the cycle ratio based
pore pressure model of Seed et al., 1975, such that the model is
a function of accumulated stress. The main advantage of the
model is that since the damage parameter is an incremental
parameter that increases with each time step, the model can be
incorporated in a time domain program for performing coupled
effective stress dynamic analyses subjected to transient motions.
There is no need to define equivalent number of cycles a priori.
The model, which requires three parameters, is very robust
since it only requires the
CSR
–
N
curve determined from stress-
controlled cyclic tests. The process of selecting the parameters
was also outlined in detail. The model and the parameter
selection process were validated through comparisons with
measurements from published and non-published laboratory test
data. It was shown that the model and parameter selection
process can reliably predict pore pressure generation under
cyclic loading.
Robertson P.K. and Campanella R.G. 1985. Liquefaction potential of
sands using the CPT.
Journal of Geotechnical Engineering
111 (3),
384-403.
Seed H.B., Idriss I.M. and Arango I. 1983. Evaluation of liquefaction
potential using field performance data.
Journal of Geotechnical
Engineering
109 (3), 458-482.
Seed H.B., Idriss I.M., Makdisi F. and Banerjee N. 1975a.
Representation of irregular stress time histories by equivalent
uniform stress series in liquefaction analyses
. Earthquake
Engineering Research Center, University of California, Berkeley,
California.
Seed H.B. and Lee K.L. 1966. Liquefaction of saturated sands during
cyclic loading.
Journal of the Soil Mechanics and Foundations
Division
92 (SM3), 25-58.
Seed H.B., Martin P.P. and Lysmer J. 1975b.
The generation and
dissipation of pore water pressures during soil liquefaction
. EERC
75-29 California.
Troncoso J. and Verdugo R. 1985. Silt content and dynamic behavior of
tailing sands.
12th International Conference on Soil Mechanics and
Foundation Engineering
, 4.
Xenaki V. and Athanasopoulos G. 2003. Liquefaction resistance of
sand-silt mixtures: an experimental investigation of the effect of
fines.
Soil Dynamics and Earthquake Engineering
23 (3), 1-12.
6 ACKNOWLEDGEMENTS
This research was supported by Korea Research Foundation
Grant:
Development of algorithm for assessment of seismic
slope stability
(2011-0012486).
7 REFERENCES
Booker J.R., Rahman M. and Seed H.B. 1976.
GADFLEA: a computer
program for the analysis of pore pressure generation and
dissipation during cyclic or earthquake loading
. California Univ.,
Berkeley (USA). Earthquake Engineering Research Center.
Carraro J., Bandini P. and Salgado R. 2003. Liquefaction resistance of
clean and nonplastic silty sands based on cone penetration
resistance.
Journal of geotechnical and geoenvironmental
engineering
129 (11), 965-976.
Derakhshandi M., Rathje E.M., Hazirbaba K. and Mirhosseini S. 2008.
The effect of plastic fines on the pore pressure generation
characteristics of saturated sands.
Soil Dynamics and Earthquake
Engineering
28 (5), 376-386.
Dobry R., Pierce W.G., Dyvik R., Thomas G.E. and Ladd R.S. 1985a.
Pore pressure model for cyclic straining of sand.
Dobry R., Vasquez-Herrera A., Mohamad R. and Vucetic M. 1985b.
Liquefaction flow failure of silty sand by torsional cyclic tests.
Advances in the art of testing soils under cyclic conditions
, 29-50.
