Comparison of two criteria for internal stability of granular soil

Abstract

Internal instability describes the loss of soil particles as a result of seepage. Two criteria are commonly used to determine the potential for such instability within a granular soil that is subject to seepage flow. The criteria are similar, in that they both require an evaluation of the slope of the grain-size distribution curve. However, the manner in which the evaluation is made yields a subtle difference between the respective methods. Comparison of the methods reveals that the difference can have implications for evaluation of broadly graded soils, and guidance is suggested for their use with greater confidence in engineering practice.

Microstructural analysis of sands with varying degrees of internal stability

“…This is correct. They note that empirical evidence from Li & Fannin (2008) suggests that the Kézdi (1979) criterion has proven to be accurate for gap-graded soils such as those tested here. Were widely graded soils to be tested, it would certainly be sensible to include an assessment according to the Kenney and Lau criterion.…”

“…The Li & Fannin (2008) method, which is a hybrid of the Kézdi and Kenney and Lau methods validated against an extensive experimental database, does not result in a single variable representing internal instability, so, although accurate, has not been investigated as a potential proxy for soil fabric.…”

“…Chang & Zhang (2013) Kenney & Lau (1985, 1986 or (D c35 /d f 85 ) min as suggested by Dallo et al (2013). Because of the uncertainty associated with Kézdi's method, other methods are employed to assess the internal stability of the soils tested by the authors, namely Kenney & Lau (1985, 1986, Li & Fannin (2008) and Dallo et al (2013) methods.The Kenney and Lau method is an accurate one, as stated by Li (2008), Indraratna et al (2011 and Dallo et al (2013). The method of Li and Fannin is also accurate and has been verified against a large number of field and laboratory tests (Li et al, 2009); it is currently being evaluated for adoption in engineering practice (Semar et al, 2010).…”

“…Chang & Zhang (2013) Kenney & Lau (1985, 1986 or (D c35 /d f 85 ) min as suggested by Dallo et al (2013). Because of the uncertainty associated with Kézdi's method, other methods are employed to assess the internal stability of the soils tested by the authors, namely Kenney & Lau (1985, 1986, Li & Fannin (2008) and Dallo et al (2013) methods.…”

Conceptual considerations of evaluate internal erosion phenomenon via no-erosion filter test and continuing erosion filter test

“…Taken collectively, the state-ofpractice and the state-of-art comprise a total of six methods (Kezdi, 1979;Sherard, 1979;Lau, 1985, 1986;Burenkova, 1993;Li and Fannin, 2008;Wan and Fell, 2008 The six methods may be clustered in three groups, based on similarity of the underlying concepts: (i) Kezdi (1979) and Sherard (1979); (ii) Lau (1985, 1986), and its adaptation by Li and Fannin (2008); and (iii) Burenkova (1993), and its adaptation by Wan and Fell (2008).…”