Standard penetration test procedures and the effects in sands of overburden pressure, relative density, particle size, ageing and overconsolidation

Granted that good site control is exercised in carrying out the standard penetration test the energy delivered to the sampler, and therefore the blow count obtained in any given sand deposit at a particular effective overburden pressure, can still vary to a significant extent depending on the method of releasing the hammer, on the type of anvil and on the length of rods (if less than 10 m). For consistency it is essential to correct the observed blow count N to the value which would have been measured using a specified rod energy. A recommended value, which should be recognized internation- ally, is 60% of the free-fall energy of the standard hammer weight and drop. The corrected blow count is then designated as N60 and the normalized value (N1)60 at unit effective pressure (1 kg/cm2 or 100 kPa) may be regarded as a basic characteristic of the sand. Factors controlling the rod energy ratio are examined in detail and methods of deriving N60 values are developed. An examination of selected field and laborat...

[1]  R B Peck,et al.  DISCUSSION OF SETTLEMENT OF SPREAD FOOTINGS ON SAND , 1969 .

[2]  時松 孝次,et al.  Empirical Correlation of Soil Liquefaction Based on SPT N-Value and Fines Content , 1983 .

[3]  Gfa Fletcher,et al.  STANDARD PENETRATION TEST' ITS USES AND ABUSES , 1965 .

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

[5]  O. Daramola.  Effect of consolidation age on stiffness of sand , 1980 .

[6]  P. Robertson,et al.  SPT-CPT CORRELATIONS , 1983 .

[7]  J. Schmertmann,et al.  Energy Dynamics of SPT , 1979 .

[8]  時松 孝次,et al.  SPT PRACTICE SURVEY AND COMPARATIVE TESTS , 1983 .

[9]  S. Serota.  Discussion: The Dynamic Penetration Test: a Standard that is not Standardized , 1971 .

[10]  Kenji Ishihara,et al.  CYCLIC STRENGTH OF UNDISTURBED SANDS OBTAINED BY A PISTON SAMPLER , 1979 .

[11]  L. Ishihara,et al.  Stability of Natural Deposits during Earthquakes , 1985 .

[12]  H. J. Gibbs,et al.  Research on determining the density of sands by spoon penetration testing , 1956 .

[13]  H. Dines.  ‘Soil’ Mechanics , 1944, Nature.

[14]  石原 研而,et al.  CASE STUDIES OF LIQUEFACTION IN THE 1964 NIIGATA EARTHQUAKE , 1981 .

[15]  K. Ishihara,et al.  Cyclic Strengths of Undisturbed Sands Obtained by Large Diameter Sampling , 1978 .

[16]  Serotas,et al.  SPT PRACTICE MEETS CRITICAL REVIEW , 1973 .

[17]  Riley M. Chung,et al.  Influence of SPT Procedures in Soil Liquefaction Resistance Evaluations , 1985 .

[18]  William D. Kovacs,et al.  VELOCITY MEASUREMENT OF FREE-FALL SPT HAMMER , 1979 .

[19]  時松 孝次,et al.  UNDRAINED CYCLIC SHEAR STRENGTH OF A DENSE NIIGATA SAND , 1984 .

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

[21]  William D. Kovacs,et al.  SPT hammer energy measurement , 1982 .

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

[23]  Daniele Veneziano,et al.  Estimation of SPT-N and Relative Density , 1981 .

[24]  C.R.I. Clayton,et al.  DYNAMIC PENETRATION RESISTANCE AND THE PREDICTION OF THE COMPRESSIBILITY OF A FINE-GRAINED SAND - A LABORATORY STUDY , 1985 .

[25]  John H. Schmertmann,et al.  Static Cone to Compute Static Settlement over Sand , 1970 .