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Failure Mechanism and Bearing Capacity of Shallow Foundation on Poorly Cemented Sandstone

Published online by Cambridge University Press:  05 May 2011

J.-C. Chang*
Affiliation:
Department of Civil Engineering, National Chiao Tung University, Hsinchu, Taiwan 30010, R.O.C.
J.-J. Liao*
Affiliation:
Department of Civil Engineering, National Chiao Tung University, Hsinchu, Taiwan 30010, R.O.C.
Y.-W. Pan*
Affiliation:
Department of Civil Engineering, National Chiao Tung University, Hsinchu, Taiwan 30010, R.O.C.
*
*Ph.D. candidate
*Professor
*Professor
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Abstract

This paper aims to investigate the failure mechanism of a shallow foundation on poorly cemented sandstone and to propose an upper bound solution for the bearing capacity of the foundation. A series of laboratory material and load-bearing model tests with specimens made of artificial rock mimic undisturbed natural poorly cemented sandstone.

Based on a series of load-bearing model tests, bearing behavior and progressive failure mechanisms are investigated. It was found that the bearing behavior on poorly cemented sandstone is distinct from the cases on hard rock or on soil, and exhibits both plasticity and brittle characteristics. It is noted that the bearing capacity formulas for a shallow foundation commonly used for soil or hard rock are not appropriate for the case of poorly cemented soft sandstone. Based on the observed failure mechanism, a simplified plastic collapse mechanism is proposed and an upper-bound solution on the basis of a multi-block translation mechanism is formulated. It is shown that the upper bound solution agrees well with the experimental bearing capacity as long as a proper non-associated flow rule is adopted.

Type
Articles
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2008

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References

1.Barton, M. E., “Cohesive Sands: The Natural Transition from Sands to Sandstones,” Proceedings of Geotechnical Engineering of Hard Soil-Soft Rocks,A. A. Balkema, Rotterdam, pp. 367374 (1993).Google Scholar
2.Dobereiner, L. and Freitas, D. E., “Geotechnical Properties of Weak Sandstones,Geotechnique, 36, pp. 7994 (1986).CrossRefGoogle Scholar
3.Johnstone, I. W., Soft Rock Engineering, Comprehensive Rock Engineering, Principle, Practice and Projects, Pergamon, London (1992).Google Scholar
4.Oliveira, R., “Weak Rock Material,” Proceedings of the 26th Annual Conference of the Engineering Group of the Geological Society, A.A. Balkema, Rotterdam, pp. 5–15 (1993).Google Scholar
5.Prandtl, L., überdie harte plastischer körper. Machr. kgl. Wiss. Gottingen, Math., Phys. kl., p. 74 (1920).Google Scholar
6.Terzaghi, K., Theoretical Soil Mechanics, John Wiley and Sons, New York (1943).CrossRefGoogle Scholar
7.Meyerhof, G. G., “The Ultimate Bearing Capacity of Foundation,Geotechnique, 2, pp. 301331 (1951).CrossRefGoogle Scholar
8.Landanyi, B., “Rock Failure Under Concentrated Loading,” Proceedings of the 10th International Symposium on Rock Mechanics, Austin, Texas, New York, SME-AIME, p. 1972 (1968).Google Scholar
9.Wu, L. Y. and Tsai, Y. F., “Analysis of Earth Pressure for Retaining Wall and Ultimate Bearing Capacity for Shallow Foundation by Variation Method,Journal of Mechanics, 20, pp. 4356 (2004).CrossRefGoogle Scholar
10.Chen, W. F. and Drucker, D. C., “Bearing Capacity of Concrete Blocks or Rocks,J. Eng. Mech. Div. Proc. of ASCE, 95, pp. 995–978 (1969).Google Scholar
11.Chen, W. F., Limit Analysis and Soil Plasticity, Amsterdam, Elsevier (1975).Google Scholar
12.Ladanyi, B. and Nguyen, D., “Discussion on Paper by Coates and Gyenge, Testing Technique for Rock Mechanics,” ASTM, STP 402, Am. Soc. Testing Mats, pp. 36–40 (1966).Google Scholar
13.Choi, S. K., “The Bearing Capacity of Foundation in Weak Rock,” Ph.D. Dissertation, Dept. of Civil Eng., Monash University, Australia (1984).Google Scholar
14.Liao, J. J., Chang, J. C., Pan, Y. W., Huang, A. B. and Lin, C. P., “Loading Behavior of Shallow Foundation on Poorly Cemented Sandstone,” Proceeding of the ISRM International Symposium 3rd ARMS, Kyoto, Japan, 2, pp. 807813 (2004).Google Scholar
15.Huang, A. B., Liao, J. J., Pan, Y. W., Cheng, M. H., Hsieh, S. Y. and Peng, J. K., “Characterization of Soft Rocks in Taiwan,” Proceedings of the 4th North American Rock Mechanics Symposium, Seattle, U.S.A., pp. 83–90 (2000).Google Scholar
16.Michalowski, R. L., “An Estimate of the Influence of Soil Weight on Bearing Capacity Using Limit Analysis,Soils and Foundations, Japanese Society of Soil Mechanics and Foundation Engineering, 37, pp. 421428(1997).Google Scholar
17.Soubra, A. H., “Upper-Bound Solutions for Bearing Capacity of Foundation,ASCE, J. Geotech. Geoenviron. Eng., 125, pp. 5968 (1999).CrossRefGoogle Scholar
18.Yang, X. L. and Yin, J. H., “Upper Bound Solution for Ultimate Bearing Capacity with a Modified Hoek- Brown Failure Criterion,Int. J. Rock Mech. Mning Sci., 42, pp. 550560 (2005).CrossRefGoogle Scholar
19.Vermeer, P. A. and de Borst, R., “Non Associated Plasticity for Soils, Concrete and Rock,Heron, 29, pp. 364 (1984).Google Scholar
20.Alejano, L. R. and Alonso, E., “Considerations of the Dilatancy Angle in Rocks and Rock Massed,Int. J. RockMech. Sci., 42, pp. 481507 (2005).Google Scholar