Equations to Correct SPT-N Values Obtained from Using Non-Standard Hammer Weight – Part II

K.R. Khater, G.E. Abdelrahman, M. Abdel-Baset

In the proceedings of GeoSt. John's 2019: 72nd Canadian Geotechnical Conference

Session: Posters

ABSTRACT: SPT-N was thought-up to estimate soil parameters throughout correlations. It has standard hammer freely drops under its own weight. The theoretical energy wh is standard. Practically, measured applied energy varies from 35% to 90% of -Situ hammer became lighter, the obtained N-counts mislead. Effect of changing hammer weight on N-measured insufficiently investigated. Thus research question raises revelling unclosed gap. Hypothesis of linear relationship between, w and N could not be taken for granted. A physical model has been designed and manufactured to simulate SPT-rig. It has ability of changing hammer weight, drop height and efficiency levels. Six efficiencies are investigated. Five hammer weights are changed. Reconstituted well graded dry dense sand characterized the soil. It has been found that relationship between hammer weight and blow counts is linear. The line slope is function of efficiency. Empirical equations and curve were suggested to correct the incorrect N-values.

RÉSUMÉ: -situ devenait plus léger, les nombres de coup N obtenus seront trompant. -. Il a la capacité de changer le poids du marteau, la hauteur de chute et les niveaux reconstitué pour caractériser le sol. Il a été constaté que la relation entre le poids du marteau et le nombre de coup est corriger les valeurs N non standard.

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Cite this article:
K.R. Khater; G.E. Abdelrahman; M. Abdel-Baset (2019) Equations to Correct SPT-N Values Obtained from Using Non-Standard Hammer Weight – Part II in GEO2019. Ottawa, Ontario: Canadian Geotechnical Society.

@article{Geo2019Paper189,author = K.R. Khater; G.E. Abdelrahman; M. Abdel-Baset,title = Equations to Correct SPT-N Values Obtained from Using Non-Standard Hammer Weight – Part II,year = 2019}