Stability Evaluation during Staged Construction

Staged construction uses controlled rates of load application to increase the foundation stability of structures founded on soft cohesive soils and to improve the slope stability of tailings dams. Because construction causes positive excess pore pressures and because actual failures usually occur without significant drainage, stability analyses should compute the factor of safety against an undrained failure as the most critical and realistic condition. This requires an undrained strength analysis (USA) that treats predicted or measured in situ effective stresses as equal to consolidation stresses in order to calculate variations in undrained shear strength during construction. The recommended USA methodology requires a detailed evaluation of changes in vertical stress history profiles, uses undrained strength ratios obtained from CK0U tests to account for anisotropy and progressive failure, and is more rational than stability evaluations based on UU and CIU triaxial compression testing. Conventional effe...

[1]  Charles C. Ladd,et al.  Design Strengths for an Offshore Clay , 1985 .

[2]  Robert L. Schiffman,et al.  Behavior and Properties of Hydraulic Fills , 1988 .

[3]  S. Lacasse,et al.  State-of-the-Art Paper: Triaxial Testing Methods for Soils , 1988 .

[4]  C. Ladd,et al.  COMPARISON OF FIELD VANE AND LABORATORY UNDRAINED SHEAR STRENGTH IN SOFT SENSITIVE CLAYS , 1988 .

[5]  Leslie G. Bromwell,et al.  Consolidation of Mining Wastes , 1984 .

[6]  S. Leroueil,et al.  The stability of stage-constructed embankments on soft clays , 1978 .

[7]  Robert V. Whitman,et al.  EVALUATING CALCULATED RISK IN GEOTECHNICAL ENGINEERING , 1984 .

[8]  N. Morgenstern,et al.  The analysis of the stability of general slip surfaces , 1965 .

[9]  Guy Lefebvre,et al.  Rate effects and cyclic loading of sensitive clays , 1987 .

[10]  Serge Leroueil,et al.  Stress–strain–strain rate relation for the compressibility of sensitive natural clays , 1985 .

[11]  M. M. Baligh.  Strain Path Method , 1985 .

[12]  John T. Germaine,et al.  Stress Path Tests with Controlled Rotation of Principal Stress Directions , 1981 .

[13]  Charles C. Ladd,et al.  BEHAVIOUR OF ATCHAFALAYA LEVEES DURING CONSTRUCTION , 1977 .

[14]  D. Fredlund,et al.  Comparison of slope stability methods of analysis , 1977 .

[15]  Alan W. Bishop,et al.  The Relevance of the Triaxial Test to the Solution of Stability Problems , 1960 .

[16]  R. J. Chandler,et al.  THE IN-SITU MEASUREMENT OF THE UNDRAINED SHEAR STRENGTH OF CLAYS USING THE FIELD VANE , 1988 .

[17]  J. H. A. Crooks,et al.  Effective stress paths and yielding in soft clays below embankments , 1985 .

[18]  R A Nicholls.  Slope stability and protection , 1990 .

[19]  P. J. Rivard,et al.  Shear strength of soft fissured clays , 1978 .

[20]  R. G. Campanella,et al.  Triaxial and Plane Strain Behavior of Natural Clay , 1974 .

[21]  Antonio Gens,et al.  THE DEVELOPMENT OF A NEW HOLLOW CYLINDER APPARATUS FOR INVESTIGATING THE EFFECTS OF PRINCIPAL STRESS ROTATION IN SOILS , 1983 .

[22]  Chung-Tien Chin,et al.  Disturbances Due to “Ideal” Tube Sampling , 1987 .

[23]  Ken Been,et al.  WORK AS A CRITERION FOR DETERMINING IN SITU AND YIELD STRESSES IN CLAYS: REPLY , 1987 .

[24]  K. Terzaghi,et al.  Soil mechanics in engineering practice , 1948 .

[25]  Rn Yong,et al.  Consolidation of Soils: Testing and Evaluation , 1986 .

[26]  Ralph B. Peck,et al.  Advantages and Limitations of the Observational Method in Applied Soil Mechanics , 1969 .

[27]  Steven G. Vick,et al.  Planning, design, and analysis of tailings dams , 1983 .

[28]  M. M. Baligh.  Undrained deep penetration. I: Shear stresses , 1986 .

[29]  P W Mayhe,et al.  CAM-CLAYS PREDICTIONS OF UNDRAINED STRENGTH , 1980 .

[30]  Silvano Marchetti,et al.  In Situ Tests by Flat Dilatometer , 1980 .

[31]  S. Leroueil,et al.  The permeability of natural soft clays. Part I: Methods of laboratory measurement , 1983 .

[32]  A. Skempton.  A Study of the Geotechnical Properties of Some Post-Glacial Clays , 1948 .

[33]  L. Bjerrum,et al.  Direct Simple-Shear Tests on a Norwegian Quick Clay , 1966 .

[34]  Gholamreza Mesri,et al.  Cα/Cc Concept and K0 During Secondary Compression , 1987 .

[35]  Charles C. Ladd,et al.  New design procedure for stability of soft clays , 1974 .

[36]  R. E. Gibson,et al.  Undrained Shear Strengths Of Anisotropically Consolidated Clays , 1949 .

[37]  G. Mesri,et al.  The behaviour of embankments on clay foundations: Discussion , 1981 .

[38]  Jey K. Jeyapalan,et al.  Analyses of Flow Failures of Mine Tailings Dams , 1983 .

[39]  Vp Drnevich,et al.  Suggested Method for Performing the Flat Dilatometer Test , 1986 .

[40]  F C Townsend,et al.  Sedimentation Consolidation Models—Predictions and Validation , 1984 .

[41]  E. Spencer.  A Method of Analysis of the Stability of Embankments Assuming Parallel Inter-Slice Forces , 1967 .

[42]  M. M. Baligh.  Undrained deep penetration, II: pore pressures , 1986 .

[43]  G. Pilot,et al.  Effective stress analysis of the stability of embankments on soft soils: Reply , 1982 .

[44]  Paul W. Mayne,et al.  K o - OCR Relationships in Soil , 1982 .

[45]  Undrained Behaviour of Quickclay Underloadtests Åsrum , 1969 .

[46]  M. M. Baligh,et al.  CONSOLIDATION AFTER UNDRAINED PIEZOCONE PENETRATION. I: PREDICTION , 1986 .

[47]  Rolf Larsson,et al.  Undrained shear strength in stability calculation of embankments and foundations on soft clays , 1980 .

[48]  Roy E. Olson,et al.  Estimation of Consolidation Properties of Clay from Field Observations , 1979 .

[49]  Guy Lefebvre,et al.  A new method of sampling in sensitive clay , 1979 .

[50]  F. Tavenas,et al.  Failure of a Test Embankment On a Sensitive Champlain Clay Deposit , 1974 .

[51]  Gholamreza Mesri,et al.  Settlement analysis of embankments on soft clays , 1985 .

[52]  P. J. Moore.  THE FACTOR OF SAFETY AGAINST UNDRAINED FAILURE OF A SLOPE , 1970 .

[53]  K. Roscoe,et al.  ON THE GENERALIZED STRESS-STRAIN BEHAVIOUR OF WET CLAY , 1968 .

[54]  S. Leroueil.  Tenth Canadian Geotechnical Colloquium: Recent developments in consolidation of natural clays , 1988 .

[55]  John T. Germaine,et al.  State-of-the-Art Paper: Triaxial Testing of Saturated Cohesive Soils , 1988 .

[56]  S. Leroueil,et al.  The behaviour of embankments on clay foundations , 1980 .

[57]  T Lunne,et al.  CALIBRATION OF DILATOMETER CORRELATIONS , 1989 .

[58]  F. Tavenas,et al.  Lateral displacements in clay foundations under embankments , 1979 .

[59]  C. Ladd,et al.  Undrained Settlement of Plastic and Organic Clays , 1981 .

[60]  Robert D. Holtz,et al.  Lessons from Oedometer Tests on High Quality Samples , 1986 .

[61]  A. Bishop.  The use of the Slip Circle in the Stability Analysis of Slopes , 1955 .

[62]  A. Saada,et al.  State of the Art: Laboratory Strength Testing of Soils , 1981 .

[63]  S. Leroueil,et al.  Causes of sampling disturbance and design of a new sampler for sensitive soils , 1981 .

[64]  John Dunnicliff,et al.  Geotechnical Instrumentation for Monitoring Field Performance , 1988 .

[65]  Charles C. Ladd,et al.  Corrected Field Vane Strength for Embankment Design , 1983 .

[66]  M. Peignaud,et al.  Construction pore pressures in clay foundations under embankments. Part II: generalized behaviour , 1978 .

[67]  Akira Asaoka,et al.  OBSERVATIONAL PROCEDURE OF SETTLEMENT PREDICTION , 1978 .