Documents disponibles écrits par cet auteur

Geotechnical characterization and random field modeling of desiccated clay / Armin W. Stuedlein in Journal of geotechnical and geoenvironmental engineering, Vol. 138 N° 11 (Novembre 2012) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 11 (Novembre 2012) . - pp. 1301-1313 Titre : Geotechnical characterization and random field modeling of desiccated clay Type de document : texte imprimé Auteurs : Armin W. Stuedlein, Auteur ; Steven L. Kramer, Auteur ; Pedro Arduino, Auteur Année de publication : 2013 Article en page(s) : pp. 1301-1313 Note générale : Géotechnique Langues : Anglais (eng) Mots-clés : Cone  penetration  tests  Site  investigation  Soil  properties  Statistics  Stochastic  models Résumé : An extensive set of in situ and laboratory test data is presented for a footing load test site east of Houston, Texas, in desiccated Beaumont clay. The in situ test program included standard and cone penetration tests (CPTs), the latter of which was selected for statistical analysis to produce vertical and horizontal random field model parameters for corrected cone tip resistance. Given the relatively high sampling frequency of the cone tip resistance in the vertical direction, the vertical random field model parameters were determined using the modified Bartlett’s test statistic with fitted autocorrelation models subject to a strict fitting criterion. Horizontal random field model parameters were generated by collapsing the two-dimensional distribution of the CPTs to a one-dimensional representation and by using less stringent evaluation of the autocorrelation. The results of this study indicate that Beaumont clay exhibits greater inherent spatial variability than previously reported at other clay sites, which is attributed to the secondary structure of the desiccated clay. A companion paper discusses the performance of a footing load test in the context of spatial and transformation uncertainty. ISSN : 1090-0241 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000723 [article] Geotechnical characterization and random field modeling of desiccated clay [texte imprimé] / Armin W. Stuedlein, Auteur ; Steven L. Kramer, Auteur ; Pedro Arduino, Auteur . - 2013 . - pp. 1301-1313. Géotechnique Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 11 (Novembre 2012) . - pp. 1301-1313 Mots-clés : Cone  penetration  tests  Site  investigation  Soil  properties  Statistics  Stochastic  models Résumé : An extensive set of in situ and laboratory test data is presented for a footing load test site east of Houston, Texas, in desiccated Beaumont clay. The in situ test program included standard and cone penetration tests (CPTs), the latter of which was selected for statistical analysis to produce vertical and horizontal random field model parameters for corrected cone tip resistance. Given the relatively high sampling frequency of the cone tip resistance in the vertical direction, the vertical random field model parameters were determined using the modified Bartlett’s test statistic with fitted autocorrelation models subject to a strict fitting criterion. Horizontal random field model parameters were generated by collapsing the two-dimensional distribution of the CPTs to a one-dimensional representation and by using less stringent evaluation of the autocorrelation. The results of this study indicate that Beaumont clay exhibits greater inherent spatial variability than previously reported at other clay sites, which is attributed to the secondary structure of the desiccated clay. A companion paper discusses the performance of a footing load test in the context of spatial and transformation uncertainty. ISSN : 1090-0241 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000723

Reliability of spread footing performance in desiccated clay / Armin W. Stuedlein in Journal of geotechnical and geoenvironmental engineering, Vol. 138 N° 11 (Novembre 2012) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 11 (Novembre 2012) . - pp. 1314-1325 Titre : Reliability of spread footing performance in desiccated clay Type de document : texte imprimé Auteurs : Armin W. Stuedlein, Auteur ; Steven L. Kramer, Auteur ; Pedro Arduino, Auteur Année de publication : 2013 Article en page(s) : pp. 1314-1325 Note générale : Géotechnique Langues : Anglais (eng) Mots-clés : Reliability-based  design  Bearing  capacity  Displacement  Transformation  uncertainty  Geostatistics  Probability  Failure Résumé : To advance the use of reliability-based design procedures, it is necessary to evaluate the sources of the design parameter uncertainty including inherent variability, measurement error, and transformation uncertainty. The results of a probabilistic evaluation of undrained footing bearing performance are discussed in the context of an extensive test site characterization described in a companion paper. Kriged cone tip resistance values are transformed into design parameters using a second-moment probabilistic approach and compared with the parameters obtained from the laboratory test analyses on specimens retrieved from the test site. The spatial, measurement, and transformation uncertainty are incorporated into probabilistic finite-element and bearing capacity analyses in which the results are compared against a full-scale load test performed at the test site. The results indicate that the reliable assessment of the spread footing response depends to a large degree on the assumed strength anisotropy and soil layering. A comparison of the probabilistic estimates of the bearing capacity to deterministic estimates developed from the correlations and average design parameters indicate that the consideration of uncertainty results in a desirable prediction accuracy. ISSN : 1090-0241 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000706 [article] Reliability of spread footing performance in desiccated clay [texte imprimé] / Armin W. Stuedlein, Auteur ; Steven L. Kramer, Auteur ; Pedro Arduino, Auteur . - 2013 . - pp. 1314-1325. Géotechnique Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 11 (Novembre 2012) . - pp. 1314-1325 Mots-clés : Reliability-based  design  Bearing  capacity  Displacement  Transformation  uncertainty  Geostatistics  Probability  Failure Résumé : To advance the use of reliability-based design procedures, it is necessary to evaluate the sources of the design parameter uncertainty including inherent variability, measurement error, and transformation uncertainty. The results of a probabilistic evaluation of undrained footing bearing performance are discussed in the context of an extensive test site characterization described in a companion paper. Kriged cone tip resistance values are transformed into design parameters using a second-moment probabilistic approach and compared with the parameters obtained from the laboratory test analyses on specimens retrieved from the test site. The spatial, measurement, and transformation uncertainty are incorporated into probabilistic finite-element and bearing capacity analyses in which the results are compared against a full-scale load test performed at the test site. The results indicate that the reliable assessment of the spread footing response depends to a large degree on the assumed strength anisotropy and soil layering. A comparison of the probabilistic estimates of the bearing capacity to deterministic estimates developed from the correlations and average design parameters indicate that the consideration of uncertainty results in a desirable prediction accuracy. ISSN : 1090-0241 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000706

Simplified approximation procedure for performance-based evaluation of liquefaction potential / Roy T. Mayfield in Journal of geotechnical and geoenvironmental engineering, Vol. 136 N° 1 (Janvier 2010) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 136 N° 1 (Janvier 2010) . - pp. 140-150 Titre : Simplified approximation procedure for performance-based evaluation of liquefaction potential Type de document : texte imprimé Auteurs : Roy T. Mayfield, Auteur ; Steven L. Kramer, Auteur ; Yi-Min Huang, Auteur Article en page(s) : pp. 140-150 Note générale : Géotechnique Langues : Anglais (eng) Mots-clés : Earthquakes  Liquefaction  Sands  Hazard  analysis Index. décimale : 624.1 Infrastructures.Ouvrages en terre. Fondations. Tunnels Résumé : Performance-based procedures for evaluation of liquefaction potential have been shown to provide more consistent and accurate indications of the actual likelihood of liquefaction in areas of different seismicity than conventional procedures. The process of performing a complete site-specific performance-based evaluation of liquefaction potential, however, requires numerous calculations involving quantities that many geotechnical engineers are not familiar with. This paper shows how the results of complete performance-based analyses can be expressed in terms of a scalar parameter corresponding to a particular element of soil in a reference soil profile, and presents procedures for adjustment of that parameter to account for site-specific conditions that differ from those of the reference profile. The procedures are shown to closely approximate the results of complete site-specific performance-based evaluations. Engineers can then use mapped values of the scalar parameter, along with the recommended adjustment procedure, to realize the benefits of a performance-based evaluation without having to actually perform the performance-based calculations. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.aip.org/vsearch/servlet/VerityServlet?KEY=JGGEFK&smode=strres [...] [article] Simplified approximation procedure for performance-based evaluation of liquefaction potential [texte imprimé] / Roy T. Mayfield, Auteur ; Steven L. Kramer, Auteur ; Yi-Min Huang, Auteur . - pp. 140-150. Géotechnique Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 136 N° 1 (Janvier 2010) . - pp. 140-150 Mots-clés : Earthquakes  Liquefaction  Sands  Hazard  analysis Index. décimale : 624.1 Infrastructures.Ouvrages en terre. Fondations. Tunnels Résumé : Performance-based procedures for evaluation of liquefaction potential have been shown to provide more consistent and accurate indications of the actual likelihood of liquefaction in areas of different seismicity than conventional procedures. The process of performing a complete site-specific performance-based evaluation of liquefaction potential, however, requires numerous calculations involving quantities that many geotechnical engineers are not familiar with. This paper shows how the results of complete performance-based analyses can be expressed in terms of a scalar parameter corresponding to a particular element of soil in a reference soil profile, and presents procedures for adjustment of that parameter to account for site-specific conditions that differ from those of the reference profile. The procedures are shown to closely approximate the results of complete site-specific performance-based evaluations. Engineers can then use mapped values of the scalar parameter, along with the recommended adjustment procedure, to realize the benefits of a performance-based evaluation without having to actually perform the performance-based calculations. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.aip.org/vsearch/servlet/VerityServlet?KEY=JGGEFK&smode=strres [...]