Fissure Parameters in Stiff Clays under Compression
Publication: Journal of Geotechnical Engineering
Volume 115, Issue 9
Abstract
Stiff clays and shales forming part of natural slopes and earth dams contain fissures in their structure. Very little is known about the effect that fissure parameters such as orientation, length, number of fissures, and their mode of arrangement have on the unconfined compressive strength of stiff clays and shales. This study reports laboratory investigations designed to understand the effect that such fissure parameters have on the unconfined compressive strength of stiff fissured clays. To this end, prismatic samples of brittle kaolinite clay with preexisting cracks are tested in the laboratory under uniaxial compressive stress conditions. It is found that the orientation, length, number, and arrangement of cracks in a clay sample has a marked influence on its unconfined compressive strength. The laboratory results indicate that: (1) There is a critical crack orientation in a sample at which the uniaxial compressive strength reaches a minimum value; (2) the longer the length of a crack or the larger the number of cracks in a sample, the lower is its confined compressive strength; and (3) samples with cracks arranged in a leftstepping manner are weaker in compression than samples containing right‐stepping cracks.
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References
1.
Ashby, M. F., and Verral, R. A. (1977). “Micromechanisms of flow and fracture and their relevance to the rheology of the upper mantle.” Philos. Trans. Royal Soc. of London, 288A, 59–95.
2.
Bishop, A. W. (1966). “The strength of soils as engineering materials.” Geotechnique, 16(2), 91–128.
3.
Bishop, A. W., and Garga, V. K. (1969). “Drained tensile tests in London clay.” Geotechnique, 19(2), 309–313.
4.
Brace, W. F., and Bombolakis, E. G. (1963). “A note on brittle crack growth in compression.” J. Geophys. Res., 68(12), 3709–3713.
5.
Covarrubias, S. W. (1969). “Cracking of earth and rockfill dams.” Harvard Soil Mech. Series, 82.
6.
Duncan, J. M., and Dunlop, P. (1969). “Slopes in stiff‐fissured clays and shales.” J. Soil Mech. and Found. Engrg. Div., ASCE, 95(2), 467–491.
7.
Gdoutos, E. E. (1984). Problems of mixed mode crack propagation. Martinus Nijhoff Publishers, The Hague, Holland, 11–21.
8.
Ingraffea, A. R., and Heuze, F. E. (1980). “Finite element models for rock fracture mechanics.” Int. J. Numer. Anal. Methods Geomech., 4(1), 25–43.
9.
Kobayashi, S. (1970). “Fracture criteria for anisotropic rocks.” Memoirs of the Faculty of Engrg., Kyoto Univ., Kyoto, Japan, 32(3), 307–333.
10.
Kulhawy, F. H., and Gurtowski, T. M. (1976). “Load transfer and hydraulic fracturing in zoned dams.” J. Geotech. Engrg. Div., ASCE, 102(9), 963–974.
11.
Marsland, A. (1972). “The shear strength of stiff fissured clays.” Stress strain behaviour of soils, R. H. G. Parry, ed., G. T. Foulis and Co., London, England, 59–68.
12.
Morgenstern, N. (1977). “Slopes and excavations in heavily overconsolidated clays.” Proc., Ninth Int. Conference on Soil Mech. and Found. Engrg., State of The Art Report, 2, Tokyo, Japan, 567–581.
13.
Nemat‐Nasser, S., and Horii, H. (1982). “Compression‐induced nonplanar crack extension with application to splitting, exfoliation and rockburst.” J. Geophys. Res., 87(B8), 6805–6821.
14.
Peterson, R., et al. (1966). “Limitations of laboratory shear strength in evaluating stability of high plastic clays.” Proc. ASCE Res. Conference on the Shear Strength of Cohesive Soils, Boulder, Colo., 765–791.
15.
Rizkallah, V. (1977). “Stress strain behavior of fissured stiff clays.” Proc. Ninth Int. Conference on Soil Mech. and Found. Engrg., 1, 217–220.
16.
Sherard, J. L. (1973). “Embankment dam cracking.” Embankment dam engineering, Casagrande Volume, R. C. Hirschfeld and S. J. Poulos, eds., Wiley‐Interscience, New York, N.Y., 271–353.
17.
Sih, G. C., and Liebowitz, H. (1968). “Mathematical theories of brittle fracture.” Fracture, H. Liebowitz, ed., Vol. II, Academic Press, New York, N.Y., 67–190.
18.
Silvestri, V. (1980). “The long‐term stability of a cutting slope in an overconsolidated sensitive clay.” Can. Geotech. J., 17(3), 337–351.
19.
Skempton, A. W. (1964). “Long‐term stability of clay slopes.” Geotechnique, 14(2), 77–102.
20.
Skempton, A. W., and LaRochelle, P. (1965). “The Bradwell slip: A short‐term failure in London clay.” Geotechnique, 15(3), 221–242.
21.
Terzaghi, K. (1936). “Stability of slopes in natural clay.” Proc. 1st Int. Conference on Soil Mech. and Found. Engrg., 1, Cambridge, Mass., 161–165.
22.
Vallejo, L. E. (1985). “Fissure interaction and progressive failure of slopes.” Proc. 11th Int. Conference on Soil Mech. and Found. Engrg., 4, San Francisco, Calif., 2353–2356.
23.
Williams, A. A. B., and Jennings, J. E. (1977). “The in‐situ shear behaviour of fissured soils.” Proc. Ninth Int. Conference on Soil Mech. and Found. Engrg., 2, 169–176.
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Published In
Journal of Geotechnical Engineering
Volume 115 • Issue 9 • September 1989
Pages: 1303 - 1317
Copyright
Copyright © 1989 ASCE.
History
Published online: Sep 1, 1989
Published in print: Sep 1989
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