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Influence of rocking motion on vibratory roller-based measurement of soil stiffness / Norman W. Facas in Journal of engineering mechanics, Vol. 136 N° 7 (Juillet 2010) 

Public ISBD [article]  in Journal of engineering mechanics > Vol. 136 N° 7 (Juillet 2010) . - pp. 898-905 Titre : Influence of rocking motion on vibratory roller-based measurement of soil stiffness Type de document : texte imprimé Auteurs : Norman W. Facas, Auteur ; Paul J. van Susante, Auteur ; Michael A. Mooney, Auteur Article en page(s) : pp. 898-905 Note générale : Mécanique appliquée Langues : Anglais (eng) Mots-clés : Vibration  Soil  compaction  Parameters  Models  Stiffness  Measurement  Kinematics. Résumé : Experimental data have shown that vibratory roller compactors often exhibit rotational kinematics in addition to translation during operation. This rotation is not considered in roller-integrated measurement systems that estimate soil stiffness based on drum vibration. To model and explore the effect of rotation, a lumped parameter roller/soil model was developed. The machine parameters for this model were tuned from suspended drum testing that isolated the drum from the ground. The model was then verified using field data collected over a range of excitation frequencies on spatially homogenous soil, and over transversely heterogeneous soil using one excitation frequency. Rotational motion was found to significantly influence roller-integrated measurement of soil stiffness based on single position drum vibration data. Rotational motion causes single position measurement system results to be nonunique and to vary depending on the direction of roller travel. Using the model, various alternative measurement schemes were investigated. The directional dependence was eliminated by deriving a measurement at the drum's center of gravity, and dual-sided measurement is proposed to gain a measure of heterogeneity. A more theoretical approach was also created wherein the contact force between the drum and soil are measured rather then being calculated. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JENMDT000 [...] [article] Influence of rocking motion on vibratory roller-based measurement of soil stiffness [texte imprimé] / Norman W. Facas, Auteur ; Paul J. van Susante, Auteur ; Michael A. Mooney, Auteur . - pp. 898-905. Mécanique appliquée Langues : Anglais (eng) in Journal of engineering mechanics > Vol. 136 N° 7 (Juillet 2010) . - pp. 898-905 Mots-clés : Vibration  Soil  compaction  Parameters  Models  Stiffness  Measurement  Kinematics. Résumé : Experimental data have shown that vibratory roller compactors often exhibit rotational kinematics in addition to translation during operation. This rotation is not considered in roller-integrated measurement systems that estimate soil stiffness based on drum vibration. To model and explore the effect of rotation, a lumped parameter roller/soil model was developed. The machine parameters for this model were tuned from suspended drum testing that isolated the drum from the ground. The model was then verified using field data collected over a range of excitation frequencies on spatially homogenous soil, and over transversely heterogeneous soil using one excitation frequency. Rotational motion was found to significantly influence roller-integrated measurement of soil stiffness based on single position drum vibration data. Rotational motion causes single position measurement system results to be nonunique and to vary depending on the direction of roller travel. Using the model, various alternative measurement schemes were investigated. The directional dependence was eliminated by deriving a measurement at the drum's center of gravity, and dual-sided measurement is proposed to gain a measure of heterogeneity. A more theoretical approach was also created wherein the contact force between the drum and soil are measured rather then being calculated. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JENMDT000 [...]