, Volume 12, Issue 4, pp 657–667 | Cite as

Residual strength and creep behaviour on the slip surface of specimens of a landslide in marine origin clay shales: influence of pore fluid composition

As written in the answer to Question n°1, this is the title of the paper."?>Residual strength and creep behaviour on the slip surface of specimens of a landslide in marine origin clay shales: influence of pore fluid composition
  • C. Di MaioEmail author
  • G. Scaringi
  • R. Vassallo
Original Paper


Active landslides in clay shales are widespread in Mediterranean countries. One of their characteristics is that the mobilized shear strength corresponds to the residual strength. The residual friction angle of clays depends on pore fluid composition which, in formations of marine origin, could have changed after emersion from the sea because of a number of processes, e.g., contact with rain or fresh water. This study aims at evaluating the influence of pore fluid composition and of its changes on the behaviour of Costa della Gaveta landslide, used as a case study. The natural pore fluid composition was analysed; then, the influence of such composition on the residual strength, and the effects of its variation on the shear creep behaviour were investigated. The paper shows that the natural pore fluid is a composite salt solution with variable concentration. It exhibits characteristics close to those of seawater at about 30 m depth, whereas it is very dilute close to the ground surface. Salt solutions at various concentrations and distilled water were thus used to simulate in the laboratory tests the effects of the different natural pore solutions. The results show that the residual friction angle varies significantly within the field concentration range. Moreover, exposure to distilled water causes a noticeable decrease in the residual strength during tests under constant shear displacement rate. Consistently, under constant driving shear stresses, time dependent displacements are observed, evolving with primary, secondary and tertiary creep phases, characterized, respectively, by decreasing, constant and increasing displacement rates.


Residual shear strength Creep Clays Landslides Pore fluid composition 



The authors would like to thank Mr. M. Belvedere for carrying out in situ measurements. The authors are particularly grateful to Prof. S. Masi and Mr. D. Molfese who carried out chemical analyses on the salt solutions. Part of this research has been funded by the Italian Ministry of Education, University and Research (PRIN project 2010–2011: landslide risk mitigation through sustainable countermeasures). Special thanks to Prof. Luciano Picarelli for inviting us to give a lecture on this topic at MWL 2013.


  1. ASTM D422 - 63 (2007) Standard test method for particle-size analysis of soils. Book of Standards Vol 04.08Google Scholar
  2. Augustesen A, Liingaard M, Lade PV (2004) Evaluation of time-dependent behavior of soils. Int J Geomech 4(3):137–156CrossRefGoogle Scholar
  3. Bjerrum L (1954) Geotechnical properties of Norwegian marine clays. Geotechnique 4(2):49–69CrossRefGoogle Scholar
  4. Bjerrum L (1955) Stability of natural slopes in quick clay. Geotechnique 5:1–101CrossRefGoogle Scholar
  5. Bjerrum L, Rosenqvist IT (1956) Some experiments with artificially sedimented clays. Geotechnique 6(4):124–136CrossRefGoogle Scholar
  6. BS 1377–2 (1990) Methods of test for soils for civil engineering purposes. Classification tests. Part 2, Ch 4.3 & 4.4Google Scholar
  7. Cascini L, Calvello M, Grimaldi GM (2010) Groundwater modeling for the analysis of active slow-moving landslides. J Geotech Geoenviron Eng 136(9):1220–1230CrossRefGoogle Scholar
  8. Cascini L, Calvello M, Grimaldi GM (2014) Displacement trends of slow-moving landslides: classification and forecasting. J Mt Sci 11(3):592–606CrossRefGoogle Scholar
  9. Chapman DL (1913) A contribution to the theory of electrocapillarity. Philos Mag 25(6):475–481CrossRefGoogle Scholar
  10. Chen Z, Mi H, Zhang F, Wang X (2003) A simplified method for 3D slope stability analysis. Can Geotech J 40:675–683CrossRefGoogle Scholar
  11. Christian GD (1994) Analytical chemistry, 5th edn. Wiley, New YorkGoogle Scholar
  12. Comegna L, Picarelli L, Urciuoli G (2007) The mechanics of mudslides as a cyclic undrained-drained process. Landslides 4(3):217–232CrossRefGoogle Scholar
  13. Corominas J, Moya J, Ledesma A, Lloret A, Gili JA (2005) Prediction of ground displacements and velocities from groundwater level changes at the Vallcebre landslide (Eastern Pyrenees, Spain). Landslides 2:83–96CrossRefGoogle Scholar
  14. Cruden DM, Varnes DJ (1996) Landslide types and processes. In: Turner AK, Schuster RL (eds) Landslides investigation and mitigation. Transportation research board, US National Research Council. Special Report 247, Washington, DC, Ch 3, pp. 36–75Google Scholar
  15. D’Elia B (1975) Aspetti meccanici delle frane tipo “colata”. Ital Geotech J 1:32–42Google Scholar
  16. Di Maio C (1996a) Exposure of bentonite to salt solution: osmotic and mechanical effects. Geotechnique 46(4):695–707CrossRefGoogle Scholar
  17. Di Maio C (1996b) The influence of pore fluid composition on the residual shear strength of some natural clayey soils. Proc Int Symp Landslides 2:1189–1194Google Scholar
  18. Di Maio C (1998) Discussion on exposure of bentonite to salt solution: osmotic and mechanical effects. Geotechnique 48(3):433–436CrossRefGoogle Scholar
  19. Di Maio C (2004) Consolidation, swelling and swelling pressure induced by exposure of clay soils to fluids different from the pore fluid. Chemo-mechanical couplings in porous media Geomechanics and Biomechanics. Springer-Verlag, pp 19–43Google Scholar
  20. Di Maio C, Fenelli GB (1994) Residual strength of kaolin and bentonite: the influence of their constitutive pore fluid. Geotechnique 44(4):217–226CrossRefGoogle Scholar
  21. Di Maio C, Santoli L, Schiavone P (2004) Volume change behaviour of clays: the influence of mineral composition, pore fluid composition and stress state. Mech Mater 36:435–451CrossRefGoogle Scholar
  22. Di Maio C, Vassallo R, Vallario M, Pascale S, Sdao F (2010) Structure and kinematics of a landslide in a complex clayey formation of the Italian Southern Apennines. Eng Geol 116:311–322CrossRefGoogle Scholar
  23. Di Maio C, Vassallo R, Vallario M (2013) Plastic and viscous shear displacements of a deep and very slow landslide in stiff clay formation. Eng Geol 162:53–66CrossRefGoogle Scholar
  24. Geertsema M, Torrance JK (2005) Quick clay from the Mink Creek landslide near Terrace, British Columbia: geotechnical properties, mineralogy, and geochemistry. Can Geotech J 42:907–918CrossRefGoogle Scholar
  25. Gouy G (1910) Charge électrique à la surface d’un electrolyte. J Phis (Paris) 4(9):456–468Google Scholar
  26. Harbaugh AW (2005) MODFLOW-2005, The U.S. Geological Survey modular ground-water model - the Ground-Water Flow Process: U.S. Geological Survey Techniques and MethodsGoogle Scholar
  27. Hungr O, Leroueil S, Picarelli L (2014) The Varnes classification of landslide types, an update. Landslides 11(2):167–194CrossRefGoogle Scholar
  28. Iverson RM (1985) A constitutive equation for mass-movement behaviour. J Geol 93(2):143–160CrossRefGoogle Scholar
  29. Kenney TC (1967) The infuence of mineralogical composition on the residual strength of natural soils. Proc Oslo Conf on Shear Strength Properties of Natural Soils and Rocks 1:123–129. AAs & Whals Boktrykkeri, OsloGoogle Scholar
  30. Leroueil S (2001) Natural slopes and cuts: movement and failure mechanisms. Geotechnique 51(3):197–243CrossRefGoogle Scholar
  31. Mesri G, Olson RE (1970) Shear strength of montmorillonite. Geotechnique 20(3):261–270CrossRefGoogle Scholar
  32. Mitchell JK (1993) Fundamentals of soil behavior, 2nd edn. Wiley, New YorkGoogle Scholar
  33. Moore R, Brunsden D (1996) Physico-chemical effects on the behaviour of a coastal mudslide. Geotechnique 46(2):259–278CrossRefGoogle Scholar
  34. Moum J, Rosenqvist IT (1961) The mechanical properties of montmorillonitica and illitic clays related to the electrolytes of the pore water. Proc 5th Int Conf on SMFE 1:263–267Google Scholar
  35. Picarelli L, Di Maio C (2010) Deterioration processes of hard clays and clay shales. Geol Soc Lond Eng Geol Spec Publ 23:15–32. doi: 10.1144/EGSP23.3 Google Scholar
  36. Picarelli L, Di Maio C, Olivares L, Urciuoli G (2000) Properties and behaviour of tectonized clay shales in Italy. Proc 2nd Int Symp on Hard soils and soft rocks, Naples, pp 1211–1242Google Scholar
  37. Picarelli L, Urciouli G, Ramondini M, Comegna L (2005) Main features of mudslides in tectonised highly fissured clay shales. Landslides 2(1):15–30CrossRefGoogle Scholar
  38. Pilson MEQ (2013) An introduction to the chemistry of the sea, 2nd edn. Cambridge University Press, UKGoogle Scholar
  39. Rosenqvist IT (1966) The Norwegian research into the properties of quick clay—a review. Eng Geol 1:445–450CrossRefGoogle Scholar
  40. Schulz WH, McKenna JP, Kibler JD, Biavati G (2009) Relations between hydrology and velocity of a continuously moving landslide—evidence of pore-pressure feedback regulating landslide motion? Landslides 6:181–190CrossRefGoogle Scholar
  41. Sridharan A (1991) Engineering behaviour of fine grained soils. Indian Geotech J 21(1):1–136Google Scholar
  42. Sridharan A, Ventakappa Rao G (1973) Mechanisms controlling volume change of saturated clays and the role of the effective stress concept. Geotechnique 23(3):359–382CrossRefGoogle Scholar
  43. Suhaydu JN, Prior DB (1978) Explanation of submarine landslide morphology by stability analysis and rheological models. Offshore Technol Conf, Houston, pp 1075–1079Google Scholar
  44. Summa V (2006) Final report of the project “Monitoraggio della Frana di Costa della Gaveta del Comune di Potenza” (Monitoring of Costa della Gaveta Landslide in Potenza), in Italian, CNR-IMAA (National Research Council of Italy), Tito (PZ), ItalyGoogle Scholar
  45. Tika TE, Vaughan PR, Lemos LT (1996) Fast shearing of pre-existing shear zones in soil. Geotechnique 46(2):197–233CrossRefGoogle Scholar
  46. Vassallo R, Di Maio C, Comegna L, Picarelli L (2012) Some considerations on the mechanics of a large earthslide in stiff clays. Proc 11th Int and 2nd N Am Symp on Landslides and Engineered Slopes, Banff, Canada, vol 1, pp 963–968Google Scholar
  47. Vassallo R, Grimaldi GM, Di Maio C (2014) Pore water pressures induced by historical rain series in a clayey landslide: 3D modeling. Landslides. doi: 10.1007/s11069-011-9984-4
  48. Yen BC (1969) Stability of slopes undergoing creep deformation. J Soil Mech Found Div ASCE 95(4):1075–1096Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.University of BasilicataPotenzaItaly

Personalised recommendations