Limit equilibrium method - The Mechanics of Soils and Foundations - page 321

The table in Fig. 20.19(c) gives the calculations for each slice and, summing over the
whole mechanism,

583

287 tan 30 ◦ =

F s = 1.17

You should now repeat the calculations with different circles to find the lowest value of
F s . Notice that near the toe of the slope the seepage becomes approximately parallel to
the surface and there is the possibility of local instability, which should be investigated.

References
Bishop, A. W. (1955) 'The use of the slip circle in the stability analysis of earth slopes',
Geotechnique, 5 , 7-17.
Fellenius, W. (1927) Erdstatische Berechnungen , W. Ernst und Sohn, Berlin.
Janbu, N. (1973) 'Slope stability computations', in Embankment Dam Engineering , Casagrande
Memorial Volume . Hirschfield and Poulos (eds), Wiley, New York.
Morgenstern, N. R. and V. E. Price (1965) 'The analysis of the stability of general slip surfaces',
Geotechnique , 15 , 79-93.

Further reading

Atkinson, J. H. (1981) Foundations and Slopes , McGraw-Hill, London.
Bromhead, E. N. (1992) The Stability of Slopes , Taylor and Francis, London.
Heyman, J. (1972) Coulomb's Memoir on Statics , Cambridge University Press, Cambridge.