3075
Technical Committee 215 /
Comité technique 215
It is of interest that every case history for which shear
strength was found, yielded data with cohesion. It should also
be noted that the lowest cohesion is reported by Seed and
Boulanger (1992), and it is the lower bound for five case studies
reported by Howland and Landva (1992). All the case history
data led to the determination that MSW does indeed have
cohesive properties. However, no clear trendline emerged from
the data, although a general decrease in cohesion as the friction
angle increases was observed.
7 ACKNOWLEDGEMENTS
Melanie Massie and Paige Rogalski’s assistance in the
preparation of this paper is gratefully acknowledged.
8 REFERENCES
Bray, Jonathan D., Zekkos, D., Kavazanjian, E.,
Athanasopoulos, G. A., Riemer, M. F. (2010) “Shear Strength of
Municipal Solid Waste.” ASCE Journal of Geotechnical &
Environmental Engineering. June 2009.
6 COMPRESSIBLITY OF MSW
An additional factor which has not been paid much attention
is the highly compressible nature of MSW. Most of the test
data on the shear strength of MSW has been presented without
accounting for the significant volume changes that take place
associated with high confining pressures. Tests at high
confining pressures by Chen et al. (2008) (fig 3) showed that
owing to the high compressibility of MSW, volume changes at
high confining pressures are significant. Accordingly, these
high volume changes should result in changes in the unit weight
and hence in the shear strength. Bray et al. (2009) noted that the
effect of unit weight on the shear strength is significant.
Accordingly, the large compressibility of MSW would
invalidate the attempt to use a single Mohr Coulomb envelope
to tests on samples at widely varying unit weights at high
normal stresses.
Chen, Y., Zhan, T.L.T., and Ling, Wei-an, (2008), Mechanical
Properties of Municipal Solid Waste from Suzhou Landfill in China,
“Proceedings of Geo-Congress 2008, ASCE New Orleans March 9-
12, 2008.
Fassett, J. B., Leonards, G.A., and Repetto, P. C. (1994)
“Geotechnical Properties of Municipal Solid Wastes and Their Use
in Landfill Design,” Proc. WasteTech ’94, Charleston, SC, National
Solid Waste Management Association, Washington, D.C.
Howland, J. D. and Landva, A. O. (1992), “Stability Analysis of
a Municipal Solid Waste Landfill.” Proceedings, Stability and
Performance of Slopes and Embankments – II, Vol, 2, Geotechnical
Special Publication No. 31, ASCE, New York, NY.
Kav
., Bonaparte, R., and
Schmertmann, G. R. (1995) “Evaluation of MSW Properties for
Seismic Analysis” Accepted for publication, Proc. GeoEnvironment
2000, Special Geotechnical Publication, ASCE.
Kavazanjian, E, Jr., Mataxovic, N. and Bachus, R.C. (1999).
“Large-diameter static and cyclic laboratory testing of Municipal
Solid Waste.” Proceedings, Sardinia 1999, 7
th
International Waste
Management and Landfill Symposium, 4-8 October.
Mitchell, R.A., and Mitchel, J.K., (1992) “Stability Evaluation
of Waste Landfills,” Proceedings of ASCE Specialty Conference on
Stability and Performance of Slopes and Embankments – II,
Berkeley, California, June 28 – July 1.
Singh, S. and Murphy, B.J., (1990), “Evaluation of the Stability
of Sanitary Landfills,” In:
Geotechnics of Waste Fills – Theory and
Practice
, ASTM STP 1070, pp. 240-258.
Zekkos (Zeccos), D. P. (2005), Evaluation of static and dynamic
properties of Municipal Solid-Waste,” Dissertation submitted in
partial fulfillment of the requirements for the degree of Doctor of
Philosophy, Department of Civil and Environmental Engineering,
University of California, Berkeley, Fall. Also available at
Figure 3 Compression curves for the samples taken from BH5 (chen
et al, 2008).
It is therefore suggested that for high landfills, a plot of
shear strength verses depth can better represent the effect of
compressibility, unit weight, and high confining pressures than
a single Mohr Coulomb envelope. Also, field measurements of
density and shear strength supplemented with back calculation
of well documented case histories appear to be the most logical
mean of obtaining MSW strength information. These are some
of the important issues which should be considered when
applying geotechnical considerations in characterization of
shear strength of MSW.
6 CONCLUSIONS
1. It is suggested that due to the large compressibility of MSW
at high normal stresses, a single Mohr Coulomb shear
envelope for a landfill may not be applicable.
2. The use of strength versus depth plot is more appropriate for
characterizing shear strength of MSW, especially for high
landfills.
Environmental Engineering. June 2009.
6 COMPRESSIBLITY OF MSW
An additional factor which has not been paid much attention
is the highly compressible nature of MSW. Most of the test
data on the shear strength of MSW has been presented without
accounting for the significant volume changes that take place
associated with high confining pressures. Tests at high
confining pressures by Chen et al. (2008) (fig 3) showed that
owing to the high compressibility of MSW, volume changes at
high confining pressures are significant. Accordingly, these
high volume changes should result in changes in the unit weight
and hence in the shear strength. Bray et al. (2009) noted that the
effect of unit weight on the shear strength is significant.
Accordingly, the large compressibility of MSW would
invalidate the attempt to use a single Mohr Coulomb envelope
to tests on samples at widely varying unit weights at high
normal stresses.
Chen, Y., Zhan, T.L.T., and Ling, Wei-an, (2008), Mechanical
Properties of Municipal Solid Waste from Suzhou Landfill in China,
“Proceedings of Geo-Congress 2008, ASCE New Orleans March 9-
12, 2008.
Fassett, J. B., Leonards, G.A., and Repetto, P. C. (1994)
“Geotechnical Properties of Municipal Solid Wastes and Their Use
in Landfill Design,” Proc. WasteTech ’94, Charleston, SC, National
Solid Waste Management Association, Washington, D.C.
Howland, J. D. and Landva, A. O. (1992), “Stability Analysis of
a Municipal Solid Waste Landfill.” Proceedings, Stability and
Performance of Slopes and Embankments – II, Vol, 2, Geotechnical
Special Publication No. 31, ASCE, New York, NY.
Kavazanjian, E., Jr., Matasović, N., Bonaparte, R., and
Schmertmann, G. R. (1995) “Evaluation of MSW Properties for
Seismic Analysis” Accepted for publication, Proc. GeoEnvironment
2000, Special Geotechnical Publication, ASCE.
Kavazanjian, E, Jr., Mataxovic, N. and Bachus, R.C. (1999).
“Large-diameter static and cyclic laboratory testing of Municipal
Solid Waste.” Proceedings, Sardinia 1999, 7
th
International Waste
Manage ent and Landfill Symposium, 4-8 October.
Mitchell, R.A., and Mitchel, J.K., (1992) “Stability Evaluation
of Waste Landfills,” Proceedings of ASCE Specialty Conference on
Stability and Performance of Slopes and Embankments – II,
Berkeley, California, June 28 – July 1.
Singh, S. and Murphy, B.J., (1990), “Evaluation of the Stability
of Sanitary Landfills,” In:
Geotechnics of Waste Fills – Theory and
Practice
, ASTM STP 1070, pp. 240-258.
Zekkos (Zeccos), D. P. (2005), Evaluation of static and dynamic
properties of Municipal Solid-Waste,” Dissertation submitted in
partial fulfillment of the requirements for the degree of Doctor of
Philosophy, Department of Civil and Environmental Engineering,
University of California, Berkeley, Fall. Also available at
Figure 3 Compression curves for the samples taken from BH5 (chen
et al, 2008).
It is therefore suggested that for high landfills, a plot of
shear strength verses depth can better represent the effect of
compressibility, unit weight, and high confining pressures than
a single Mohr Coulomb envelope. Also, field measurements of
density and shear strength supplemented with back calculation
of well documented case histories appear to be the most logical
mean of obtaining MSW strength information. These are some
of the important issues which should be considered when
applying geotechnical considerations in characterization of
shear strength of MSW.
6 CONCLUSIONS
1. It is suggested that due to the large compressibility of MSW
at high normal stresses, a single Mohr Coulomb shear
envelope for a landfill may not be applicable.
2. The use of strength versus depth plot is more appropriate for
charact izing hear rength o MSW, especially for high
landfills.
It is of interest that every case history for w ich shear
stre g h was found, yielded data with cohesion. It shoul lso
be noted that the lowest cohesion is reported by S ed and
Boulanger (1992), and it is the lower bound for five a studies
report by Howland and Landva (1992). All the cas history
data led to the determination that MSW do s inde have
cohesive properties. However, no cl ar trendl ne emerged from
the data, although a general decrease in cohesion as the friction
angle increases was observed.
7 ACKNOWLEDGEMENTS
M l nie Massie and Paige Rogals i’s assistance in the
preparation of this paper is gratefully acknowledged.
8 REFERENCES
Bray, Jo than D., Zekkos, D., Kavazanjian, E.,
Athanasopoul s, G. A., Riemer, M. F. (2010) “Shear Strength of
Municipal Solid Waste.” ASCE Journal of Geotechnical &
Environmental Engineering. June 2009.
6 COMPRESSIBLITY OF MSW
An additional factor which has n t been paid much a tention
is the highly comp ssible nature of MSW. Most of the tes
data o the shear strength of MSW has been presented without
cc un ing for the significant volume changes tha take place
associated with high confining pressures. Tests at high
confining pressures by Chen et al. (2008) (fig 3) showed th
owing to the high compressibility of MSW, volume changes at
confining pr sures ar signifi ant. Accordingly, these
high volume c ang s should result in ch nges in the unit weig t
and hence in the shear stre g . Bray et al. (2009) noted that the
effect of unit weight on the shear s rength is significant.
Accor ingly, th large compressibility of MSW would
invalidate the attempt to use a single Mohr Coulomb envelope
to tests on samples at widely varying unit weights at high
normal stresses.
Chen, Y., Zhan, T.L.T., and Ling, ei-an, (2008), Mech ical
Properties of Municipal Solid Waste from Suzhou Landfill in China,
“Proceedings of Geo-Congress 2008, ASCE New Orleans March 9-
12, 2008
Fassett, J. B., Leona ds, G.A., and Repetto, P. C. (1994)
“Geotechnical Properties of Municipal Solid Wastes and Their Use
in Landfill Design,” Proc. WasteTech ’94, Charleston, SC, National
Soli Waste Management Association, W shington, D.C.
Howland, J. D. and Landva, A. O. (1992), “Stability Analysis of
a Municipal Solid W ste Landfill.” Proceedings, Stability and
Performance of Slopes and Embankments – II, Vol, 2, Geotechnical
SCE, New York, NY.
Kavazanjian, E., Jr., Matasović, N., Bonaparte, R., and
ch ertmann, G. R. (1995) “Evaluation of MSW Prope ties for
Seismic An ysis” Accepted for publication, Proc. GeoEnvironment
2000, Special Geotechnical Publication, ASCE.
Kavaz njian, E, Jr., Mataxovic, N. and Bachus, R.C. (1999).
“Large-diameter static and cyclic l boratory testing of Municipal
Solid Waste.” Procee ings, Sardinia 1999, 7
th
International Waste
Management and Landfill Symposium, 4-8 October.
Mitchell, R.A., and Mitchel, J.K., (1992) “ tability Evaluati
of Waste Landfills,” Proce dings of ASCE Specialty Conference on
Stabilit and Performance of Slopes and Embankments – II,
Berkeley, California, une 28 – July 1.
Singh, S. and Murphy, B.J., (1990), “Evaluation of the Stability
of Sanitary Landfills,” In:
Geotechnics of Waste Fills – Theory and
Practice
, ASTM STP 1 70, pp. 240-258.
Zekkos (Zeccos), D. P. (2005), Evaluation of static and dynamic
roperties of Municipal Solid-Waste,” Dissertation submitted in
partial fulfillm nt of the requ reme ts for the degree of Doctor of
Philosophy, Department of Civil and Environmental Engineering,
erkeley, Fall. Also available at
Figure 3 Compression curves for the samples taken from BH5 (chen
et al, 2008).
It is therefor sugg s ed that for high landfills, a plo
shear strength verses depth can better represent the effec of
compr ssibility, unit weight, and high confining pressur s han
a single Mohr Coulomb envelop . Also, field measurements f
density and sh ar strengt upplemented with back calculation
of well d cume ted case histories appear o be the most logical
mean of obtaini g MSW strength information. Thes are some
of the impor ant ssues which should be considered when
applying eotechnical considerations in characterization of
shear strength of MSW.
6 CONCLUSIONS
1. I is suggested that due to the lar e compressibility of MSW
at high n mal stresses, a single Mohr Coulomb shear
envelope for a landfill may not be applicable.
2. T e us of strength versus depth plot is more appropriate for
characterizing shear strength of MSW, especially for high
landfills.
