Residual Strength and Large-Deformation Potential of Loose Silty Sands

The authors of this paper summarize laboratory and field evidence on residual shear strength, density, and penetration resistance of very loose, water-deposited silty sands and sandy silts capable of liquefying and developing large shear deformations. A program of laboratory monotonic and cyclic undrained tests is performed on reconstituted, water-deposited, layered triaxial specimens of silty sand retrieved from the Lower San Fernando Dam. The results reveal that the soil acts contractively in shear, and both its density and steady-state strength increase quickly with consolidation pressure. These trends are confirmed for field conditions by comparison with available case histories of earthquake-induced flow failure and large lateral deformation of embankments, slopes, and mildly sloping ground. The 1971 flow slide in the Lower San Fernando Dam is reviewed in detail. The normalized Standard Penetration Index used to develop engineering charts is developed from the case histories. These charts can be applied in evaluating residual shear strength and to determine if a saturated silt-sand slope or site is likely to develop flow or large lateral deformations.

[1]  H. Bolton Seed,et al.  Design Problems in Soil Liquefaction , 1987 .

[2]  G. Yamada.  DAMAGE TO EARTH STRUCTURES AND FOUNDATIONS BY THE NIIGATA EARTHQUAKE JUNE 16, 1964, IN JNR. , 1966 .

[3]  Gonzalo Castro,et al.  Liquefaction Evaluation Procedure , 1985 .

[4]  G. Castro,et al.  On the Behavior of Soils During Earthquakes – Liquefaction , 1987 .

[5]  Ricardo Dobry,et al.  Engineering Evaluation of Permanent Ground Deformations Due to Seismically Induced Liquefaction , 1992 .

[6]  Closure of "Steady-State Strength Analysis of Lower San Fernando Dam Slide" , 1992 .

[7]  E. Harp,et al.  The Borah Peak, Idaho Earthquake of October 28, 1983—Liquefaction , 1985 .

[8]  N. Morgenstern,et al.  Progressive Failure of Lower San Fernando Dam , 1993 .

[9]  B. Romanowicz,et al.  Importance of on scale observations of first arriving Rayleigh wave trains for source studies: Example of the Chilean Event of March 3, 1985, Observed on the Geoscope and Ida Networks , 1986 .

[10]  K. Ishihara.  Liquefaction and flow failure during earthquakes. , 1993 .

[11]  W. F. Marcuson,et al.  Evaluation and Use of Residual Strength in Seismic Safety Analysis of Embankments , 1990 .

[12]  T. Leslie Youd,et al.  Liquefaction Sites, Imperial Valley, California , 1983 .

[13]  Peter K. Robertson,et al.  Seismic cone penetration test for evaluating liquefaction potential under cyclic loading , 1992 .

[14]  D. L. Anderson,et al.  Theoretical Basis of Some Empirical Relations in Seismology by Hiroo Kanamori And , 1975 .

[15]  H. Bolton Seed,et al.  Evaluation of Liquefaction Potential Using Field Performance Data , 1983 .

[16]  G Mesri,et al.  Closure of "Undrained Shear Strength of Liquefied Sands for Stability Analysis" , 1992 .

[17]  F. Y. Yokel,et al.  Prediction of pore water pressure buildup and liquefaction of sands during earthquakes by the cyclic strain method , 1982 .

[18]  Steven F. Bartlett,et al.  EMPIRICAL PREDICTION OF LIQUEFACTION-INDUCED LATERAL SPREAD , 1995 .

[19]  T. Middlebrooks.  Fort Peck Slide , 1942 .

[20]  Robert V. Whitman,et al.  Overburden Correction Factors for SPT in Sand , 1986 .

[21]  T L Youd,et al.  MAPPING LIQUEFACTIONINDUCED GROUND FAILURE POTENTIAL , 1978 .

[22]  H. Bolton Seed,et al.  Closure of "Soil Liquefaction and Cyclic Mobility Evaluation for Level Ground during Earthquakes" , 1979 .

[23]  Goodarz Ahmadi,et al.  Random response analysis of frictional base isolation system , 1990 .

[24]  T. Leslie Youd,et al.  Mapping of Liquefaction Severity Index , 1987 .

[25]  S. Poulos,et al.  Liquefaction Resistance of Thickened Tailings , 1985 .

[26]  R. D. Hryciw,et al.  Liquefaction and Flow Failure During Seismic Exploration , 1990 .