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Modeling rock fracture intersections and application to the boston area / Herbert H. Einstein 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. 1415-1421 Titre : Modeling rock fracture intersections and application to the boston area Type de document : texte imprimé Auteurs : Herbert H. Einstein, Auteur ; Jean-Louis Z. Locsin, Auteur Année de publication : 2013 Article en page(s) : pp. 1415-1421 Note générale : Géotechnique Langues : Anglais (eng) Mots-clés : Fractures  Intersections  Boston  geology Résumé : An algorithm for determining the intersections between fractures is presented in this paper. The algorithm is implemented in GEOFRAC, a stochastic fracture pattern-modeling program. Previously, GEOFRAC allowed one to subdivide a fracture network into isolated subnetworks to assess connectivity. A new GEOFRAC feature can be used to analyze length and orientation distributions of the fracture intersections. Connectivity parameters such as the number of intersections per unit volume, C1, and the intersection length per unit volume can be calculated. Intersections and connectivity are important because they govern the fluid flow and stability behavior of rock masses. The program is used to model fracture intersections in the Boston area. The simulations show that for fractures in the Boston area, the mean fracture intersection length ranges from 0.5 to 0.7 m. The results also show that the relative frequency of long intersections (>2.0 m) increases with increasing modeling volume size. In contrast to these effects of volume, it appears that intersection orientation is not affected by the volume being considered. ISSN : 1090-0241 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000699 [article] Modeling rock fracture intersections and application to the boston area [texte imprimé] / Herbert H. Einstein, Auteur ; Jean-Louis Z. Locsin, Auteur . - 2013 . - pp. 1415-1421. Géotechnique Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 11 (Novembre 2012) . - pp. 1415-1421 Mots-clés : Fractures  Intersections  Boston  geology Résumé : An algorithm for determining the intersections between fractures is presented in this paper. The algorithm is implemented in GEOFRAC, a stochastic fracture pattern-modeling program. Previously, GEOFRAC allowed one to subdivide a fracture network into isolated subnetworks to assess connectivity. A new GEOFRAC feature can be used to analyze length and orientation distributions of the fracture intersections. Connectivity parameters such as the number of intersections per unit volume, C1, and the intersection length per unit volume can be calculated. Intersections and connectivity are important because they govern the fluid flow and stability behavior of rock masses. The program is used to model fracture intersections in the Boston area. The simulations show that for fractures in the Boston area, the mean fracture intersection length ranges from 0.5 to 0.7 m. The results also show that the relative frequency of long intersections (>2.0 m) increases with increasing modeling volume size. In contrast to these effects of volume, it appears that intersection orientation is not affected by the volume being considered. ISSN : 1090-0241 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000699

Validation of centrifuge model scaling for soil systems via trapdoor tests / Geraldo R. Iglesia in Journal of geotechnical and geoenvironmental engineering, Vol. 137 N° 11 (Novembre 2011) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 137 N° 11 (Novembre 2011) . - pp. 1075-1089 Titre : Validation of centrifuge model scaling for soil systems via trapdoor tests Type de document : texte imprimé Auteurs : Geraldo R. Iglesia, Auteur ; Herbert H. Einstein, Auteur ; Robert V. Whitman, Auteur Année de publication : 2012 Article en page(s) : pp. 1075-1089 Note générale : Géotechnique Langues : Anglais (eng) Mots-clés : Centrifuge  modeling  Trapdoor  tests  Physical  modeling  Scaling  laws  Granular  media Résumé : The validity of centrifuge modeling of soil systems is investigated by means of a “yielding trapdoor” setup similar to the one used by previous researchers for examining soil arching. A modeling-of-models exercise is thus carried out in accordance with centrifuge scaling requirements. This parametric study also includes the effects of g-level, grain-size, trapdoor width, and overburden depth. Particle-size scaling may be necessary to achieve full model-prototype similitude, depending on the structure-to-grain-size ratio. However, it appears that reasonable results can be achieved with centrifuge models, using the same soil as the prototype, where the structural dimensions are at least 20 times the grain size. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.org/gto/resource/1/jggefk/v137/i11/p1075_s1?isAuthorized=no [article] Validation of centrifuge model scaling for soil systems via trapdoor tests [texte imprimé] / Geraldo R. Iglesia, Auteur ; Herbert H. Einstein, Auteur ; Robert V. Whitman, Auteur . - 2012 . - pp. 1075-1089. Géotechnique Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 137 N° 11 (Novembre 2011) . - pp. 1075-1089 Mots-clés : Centrifuge  modeling  Trapdoor  tests  Physical  modeling  Scaling  laws  Granular  media Résumé : The validity of centrifuge modeling of soil systems is investigated by means of a “yielding trapdoor” setup similar to the one used by previous researchers for examining soil arching. A modeling-of-models exercise is thus carried out in accordance with centrifuge scaling requirements. This parametric study also includes the effects of g-level, grain-size, trapdoor width, and overburden depth. Particle-size scaling may be necessary to achieve full model-prototype similitude, depending on the structure-to-grain-size ratio. However, it appears that reasonable results can be achieved with centrifuge models, using the same soil as the prototype, where the structural dimensions are at least 20 times the grain size. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.org/gto/resource/1/jggefk/v137/i11/p1075_s1?isAuthorized=no