Influence of grading on the mechanical behaviour of Stava tailings

Tailings dams can be fragile structures and too often they are subject to liquefaction. The material they are composed of is rather peculiar, having a man-made origin, and their behaviour is still not very well understood. The soil from the Stava tailings dams, structures that were subject to liquefaction in 1985 causing extensive destruction, was investigated in this study as an example of tailings. Two main aspects of their behaviour have been examined: the influence of the percentage of silt and sand that compose the soil on its mechanical behaviour, and the susceptibility to liquefaction, analysing the behaviour within a critical state framework. In this paper it is shown that, as the quantity of silt increases, the slope and intercept of the normal compression line and critical state line at higher pressures decrease until an inversion of behaviour is observed, while at lower stress levels the critical state line changes its position but not its slope. This means that the effect of adding silt on the...

[1]  James R. Martin,et al.  EFFECTS OF NONPLASTIC FINES ON THE LIQUEFACTION RESISTANCE OF SANDS , 2001 .

[2]  G. Gudehus.  A COMPREHENSIVE CONSTITUTIVE EQUATION FOR GRANULAR MATERIALS , 1996 .

[3]  J. A. Sladen,et al.  The liquefaction of sands, a collapse surface approach , 1985 .

[4]  Ken Been,et al.  The critical state of sands , 1991 .

[5]  M. Coop,et al.  The mechanics of an Italian silt: an example of ‘transitional’ behaviour , 2006 .

[6]  Matthew Richard Coop,et al.  THE BEHAVIOUR OF GRANULAR SOILS AT ELEVATED STRESSES , 1993 .

[7]  S-Cr Lo,et al.  The prediction of equivalent granular steady state line of loose sand with fines , 2008 .

[8]  Pmv Ferreira,et al.  Problems in identifying the effects of structure and critical state in a soil with a transitional behaviour , 2006 .

[9]  Non-uniqueness of flow liquefaction line for loose sand , 2002 .

[10]  Jerry A. Yamamuro,et al.  STEADY-STATE CONCEPTS AND STATIC LIQUEFACTION OF SILTY SANDS , 1998 .

[11]  Jerry A. Yamamuro,et al.  Effects of nonplastic fines on static liquefaction of sands , 1997 .

[12]  Z. X. Yang,et al.  Quantifying and modelling fabric anisotropy of granular soils , 2008 .

[13]  Jian Chu,et al.  Effect of fines on instability behaviour of loose sand , 2002 .

[14]  James K. Mitchell,et al.  Fundamentals of soil behavior , 1976 .

[15]  Ken Been,et al.  A STATE PARAMETER FOR SANDS , 1985 .

[16]  Jerry A. Yamamuro,et al.  Monotonic and Cyclic Liquefaction of Very Loose Sands with High Silt Content , 2001 .

[17]  P. K. Robertson,et al.  Influence of fines on the collapse of loose sands , 1994 .

[18]  J. H. Atkinson,et al.  The mechanics of cemented carbonate sands , 1993 .

[19]  C. Polito,et al.  The Effects Of Non-Plastic and Plastic Fines On The Liquefaction Of Sandy Soils , 1999 .

[20]  Kenji Ishihara,et al.  THE STEADY STATE OF SANDY SOILS , 1996 .

[21]  T. Shenthan,et al.  Undrained Fragility of Clean Sands, Silty Sands, and Sandy Silts , 2002 .

[22]  Thiam-Soon Tan,et al.  Contribution of fines to the compressive strength of mixed soils , 2004 .

[23]  John S. Rowlinson,et al.  Chapter 3 – The critical state , 1982 .

[24]  Fumio Tatsuoka,et al.  Strength and deformation characteristics of saturated sand at extremely low pressures , 1984 .

[25]  Giovanni Tosatti,et al.  The Stava tailings dams failure, Italy, July 1985 , 1995 .

[26]  S. Kramer.  Geotechnical Earthquake Engineering , 1996 .

[27]  Yoginder P. Vaid,et al.  Fundamental factors affecting liquefaction susceptibility of sands , 2000 .

[28]  J.-M. Konrad.  SAND STATE FROM CONE PENETROMETER TESTS: A FRAMEWORK CONSIDERING GRAIN CRUSHING STRESS , 1998 .

[29]  Ken Been,et al.  Soil Liquefaction: A Critical State Approach , 2006 .