Documents disponibles écrits par cet auteur

Base stability of grout pile–reinforced excavations in soft clay / Hung-Jiun Liao in Journal of geotechnical and geoenvironmental engineering, Vol. 138 N° 2 (Fevrier 2012) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 2 (Fevrier 2012) . - pp. 184-192 Titre : Base stability of grout pile–reinforced excavations in soft clay Type de document : texte imprimé Auteurs : Hung-Jiun Liao, Auteur ; Shi-Fon Su, Auteur Année de publication : 2012 Article en page(s) : pp. 184-192 Note générale : Géotechnique Langues : Anglais (eng) Mots-clés : Clay  reinforced  with  grout  piles  Deep  excavation  Base  undrained  stability  Strength  anisotropy  Soft  clay Résumé : Grout piles are used to reinforce base soil to increase the base stability of excavations in soft clay and to reduce excavation-induced ground movements. To propose a model for the base undrained stability of deep excavation in clay reinforced with grout piles, this paper presents an anisotropic strength criterion for clay reinforced with grout piles and the upper-bound bearing capacity theory for excavation. The proposed model is capable of determining the factor of safety against base heave for an excavation with or without ground improvement for various-strength anisotropy ratios of clay and clay reinforced with grout piles. The suitability of the model is verified with five field excavation cases. Among them, four were with no ground improvement, and one was with ground improvement. Generally, the larger the ground improvement rate, the more the material strength of a grout pile can be mobilized. The factor of safety also becomes larger when the ground improvement rate is higher. However, the factor of safety becomes insensitive to the undrained shear strength of a grout pile when the improvement ratio is less than 10%. Results from the model found that the increment of factor of safety against base heave and the increment of improvement ratio is generally 1∶2. Finally, because the proposed method does not consider the influence of displacement at the retaining wall bottom and the geometry of excavation, it can be used only in excavations with the width and depth of ground improvement zone larger than 1.41Dp and 1Dp (Dp is depth of the retaining wall minus depth of excavation), respectively. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.org/gto/resource/1/jggefk/v138/i2/p184_s1?isAuthorized=no [article] Base stability of grout pile–reinforced excavations in soft clay [texte imprimé] / Hung-Jiun Liao, Auteur ; Shi-Fon Su, Auteur . - 2012 . - pp. 184-192. Géotechnique Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 2 (Fevrier 2012) . - pp. 184-192 Mots-clés : Clay  reinforced  with  grout  piles  Deep  excavation  Base  undrained  stability  Strength  anisotropy  Soft  clay Résumé : Grout piles are used to reinforce base soil to increase the base stability of excavations in soft clay and to reduce excavation-induced ground movements. To propose a model for the base undrained stability of deep excavation in clay reinforced with grout piles, this paper presents an anisotropic strength criterion for clay reinforced with grout piles and the upper-bound bearing capacity theory for excavation. The proposed model is capable of determining the factor of safety against base heave for an excavation with or without ground improvement for various-strength anisotropy ratios of clay and clay reinforced with grout piles. The suitability of the model is verified with five field excavation cases. Among them, four were with no ground improvement, and one was with ground improvement. Generally, the larger the ground improvement rate, the more the material strength of a grout pile can be mobilized. The factor of safety also becomes larger when the ground improvement rate is higher. However, the factor of safety becomes insensitive to the undrained shear strength of a grout pile when the improvement ratio is less than 10%. Results from the model found that the increment of factor of safety against base heave and the increment of improvement ratio is generally 1∶2. Finally, because the proposed method does not consider the influence of displacement at the retaining wall bottom and the geometry of excavation, it can be used only in excavations with the width and depth of ground improvement zone larger than 1.41Dp and 1Dp (Dp is depth of the retaining wall minus depth of excavation), respectively. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.org/gto/resource/1/jggefk/v138/i2/p184_s1?isAuthorized=no

Calibration of reliability-based resistance factors for flush drilled soil anchors in Taipei basin / Jianye Ching in Journal of geotechnical and geoenvironmental engineering, Vol. 134 n°9 (Septembre 2008) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 134 n°9 (Septembre 2008) . - pp. 1348-1363 Titre : Calibration of reliability-based resistance factors for flush drilled soil anchors in Taipei basin Type de document : texte imprimé Auteurs : Jianye Ching, Auteur ; Hung-Jiun Liao, Auteur ; Chia-Wei Sue, Auteur Année de publication : 2008 Article en page(s) : pp. 1348-1363 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Anchors  Pull-out  resistance  Safety  factors  Taiwan  Calibration  Drilling Résumé : The goal of this research is to calibrate the reliability-based resistance factor of flush drilled soil anchors for their ultimate pullout capacities based on in situ anchor pullout test data in the alluvial soil underlying the Taipei Basin. Efforts are taken to quantify the uncertainties with a full probabilistic analysis approach. The resistance factor is calibrated based on the in situ test results of 46 anchors with a rigorous theoretical approach which constructs the relationship between the resistance factor and failure probability. With this relationship, the reliability corresponding to the code regulation can be verified. From the results of the analysis, it is found that the borehole enlargement due to the flush drilling is quite significant: the actual diameter of the fixed anchor end may be much larger than the nominal diameter of the drilling casing. Consequently, the safety factor of 3.0, recommended by most anchor codes, is found to be too conservative. The results should be valuable for reliability-based design of flush drilled soil anchors in the Taipei Basin. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A9%2813 [...] [article] Calibration of reliability-based resistance factors for flush drilled soil anchors in Taipei basin [texte imprimé] / Jianye Ching, Auteur ; Hung-Jiun Liao, Auteur ; Chia-Wei Sue, Auteur . - 2008 . - pp. 1348-1363. Geotechnical and geoenvironmental engineering Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 134 n°9 (Septembre 2008) . - pp. 1348-1363 Mots-clés : Anchors  Pull-out  resistance  Safety  factors  Taiwan  Calibration  Drilling Résumé : The goal of this research is to calibrate the reliability-based resistance factor of flush drilled soil anchors for their ultimate pullout capacities based on in situ anchor pullout test data in the alluvial soil underlying the Taipei Basin. Efforts are taken to quantify the uncertainties with a full probabilistic analysis approach. The resistance factor is calibrated based on the in situ test results of 46 anchors with a rigorous theoretical approach which constructs the relationship between the resistance factor and failure probability. With this relationship, the reliability corresponding to the code regulation can be verified. From the results of the analysis, it is found that the borehole enlargement due to the flush drilling is quite significant: the actual diameter of the fixed anchor end may be much larger than the nominal diameter of the drilling casing. Consequently, the safety factor of 3.0, recommended by most anchor codes, is found to be too conservative. The results should be valuable for reliability-based design of flush drilled soil anchors in the Taipei Basin. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A9%2813 [...]