Correlations of SPT, CPT and DPL Data for Sandy Soil in Tanzania

In Tanzania, standard penetration test (SPT) is the most commonly used in situ test for foundation design site investigations. In an effort to increase the amount of geotechnical information at low cost, the quicker and much cheaper dynamic probing of light (DPL) hammer is sometimes performed along with SPT to supplement the expensive SPT. Nevertheless, the information gathered with DPL has been applicable only for site stratification. Recently, the static cone penetration test (CPT) has also been introduced in the country with a view to combining these methods in site investigations. In this study, side by side testing was performed with the three in situ methods and correlations established through regression analysis and arithmetic mean methods. Results indicate that DPL data correlate better with CPT than SPT data, with lower magnitudes of transformation uncertainty. The local SPT–CPT correlations compare fairly well to those in the literature. The established correlations extend the function of DPL data to analysis and design.

[2]  Fred H. Kulhawy,et al.  Characterization and Estimation of Geotechnical Variability in Ankara Clay: A Case History , 2010 .

[3]  Discussion of “CPT-DMT Correlations” by P. K. Robertson , 2011 .

[4]  Alec Westley Skempton,et al.  Standard penetration test procedures and the effects in sands of overburden pressure, relative density, particle size, ageing and overconsolidation , 1986 .

[5]  János Szendefy,et al.  Estimation of CPT resistance based on DPH results , 2009 .

[6]  Robb E.S. Moss,et al.  Normalizing the CPT for Overburden Stress , 2006 .

[7]  M. Jefferies,et al.  Use of CPTu to Estimate Equivalent SPT N60 , 1993 .

[8]  Kok-Kwang Phoon,et al.  Linking Site Investigation Efforts to Final Design Savings with Simplified Reliability-Based Design Methods , 2014 .

[9]  Douglas G. Altman,et al.  Measurement in Medicine: The Analysis of Method Comparison Studies , 1983 .

[10]  Johan Spross,et al.  Extended multivariate approach for uncertainty reduction in the assessment of undrained shear strength in clays , 2014 .

[11]  Fred H. Kulhawy,et al.  Manual on estimating soil properties for foundation design , 1990 .

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

[13]  J. David Rogers,et al.  Subsurface Exploration using the Standard Penetration Test and the Cone Penetrometer Test , 2006 .

[14]  C. T. Chin,et al.  SPT-CPT correlations for granular soils : Proc 1st International Symposium on Penetration Testing, ISOPT-1, Orlando, 20–24 March 1988 V1, P335–339. Rotterdam: A A Balkema, 1988 , 1990 .

[15]  Paul W. Mayne,et al.  In-Situ Test Calibrations for Evaluating Soil Parameters , 2006 .

[16]  Kok-Kwang Phoon,et al.  Reducing shear strength uncertainties in clays by multivariate correlations. , 2010 .

[17]  Mohamad H. Hussein,et al.  Pile Driveability and Bearing Capacity in High-Rebound Soils , 2006 .

[18]  Joseph G. Eisenhauer.  Regression through the Origin , 2003 .

[19]  P. Robertson.  Interpretation of in-situ tests – some insights , 2012 .

[20]  John H. Schmertmann,et al.  GUIDELINES FOR CONE PENETRATION TEST. (PERFORMANCE AND DESIGN) , 1978 .

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

[22]  Eslami Abou Alfazl,et al.  CPT AND CPTU DATA FOR SOIL PROFILE INTERPRETATION:REVIEW OF METHODS AND A PROPOSED NEW APPROACH , 2004 .

[23]  Kok-Kwang Phoon,et al.  Evaluation of Geotechnical Property Variability , 1999 .

[24]  Peter K. Robertson,et al.  Cone-penetration testing in geotechnical practice , 1997 .

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

[26]  N. Akça,et al.  Correlation of SPT–CPT data from the United Arab Emirates , 2003 .

[27]  Ross W. Boulanger,et al.  Relating Kα to Relative State Parameter Index , 2003 .

[28]  P. Robertson.  Interpretation of cone penetration tests — a unified approach , 2009 .

[29]  John W. Tukey,et al.  Exploratory Data Analysis. , 1979 .

[30]  G. Sanglerat,et al.  Dynamic probing: international reference test procedure : Proc 1st International Symposium on Penetration Testing, ISOPT-1, Orlando, 20–24 March 1988V1, P53–70. Rotterdam: A A Balkema, 1988 , 1990 .