An evaluation of seismic flat dilatometer and lateral stress seismic piezocone
Notice bibliographique
Résumé
The flat dilatometer (DMT) and piezocone penetration (CPTU) tests are likely to be among the most widely used in situ testing methods for soil characterization and indirect determination of geotechnical design parameters such as: strength, stiffness, permeability and compressibility. The flat dilatometer has proved to be a reliable, robust and adaptable tool, and the data obtained with this instrument is very repeatable, and easy to reduce and process. Furthermore, the addition of a seismic module to the standard flat dilatometer (SDMT) to measure the shear wave velocity (Vs) significantly complements the set of data typically obtained with a standard DMT test. Nonetheless, the experience in interpreting the combination between Vs and DMT data is fairly limited due to the recent introduction of the SDMT for commercial applications. Additionally, the estimation of the coefficient of earth pressure at rest (K₀) has been the most important application of the DMT since its introduction. However, a potential weakness of the DMT is that the derivation of K₀ is based upon empirical correlations developed some time ago and neither improvement work nor upgrade of these approaches has been performed in the last 10 years. Throughout the years several additional sensors have been developed in order to supplement the data collected with the CPTU test. Among the wide variety of sensor developed, the lateral stress module mounted behind a piezocone represents a promising tool for estimation of in situ lateral stress conditions from the interpretation of lateral stress penetration data. However, the popularity of the so called lateral stress cone has declined over the years due to constraints in both the instrumentation and the interpretation of measured data. Also, the application of this instrument remains limited to specific soils conditions and specific projects. However, the valuable experience gained throughout the years in the development and application of several lateral stress cones in combination with developments in electronics and understanding of soil behaviour allow the improvement of this type of technology. This thesis presents the results of a comprehensive laboratory and field testing programs performed by the author at several research sites located in the Lower Mainland of BC, undertaken in order to assess the performance of the seismic flat dilatometer and lateral stress seismic piezocone (LSSCPTU), built and develop at UBC. Firstly, the analysis of field measurements with the SDMT collected at several sites have demonstrated the potential for an improved soil characterization through the combination of DMT parameters and the small strain shear modulus (G₀). Additionally the usefulness of the DMT-C closing pressure for soil identification is shown. On the basis of several relationships identified from this data, a new soil type behaviour system based upon SDMT measurements is proposed. Furthermore, empirical correlations based upon fairly large and updated databases have been developed to estimate K₀ and Vs values from DMT parameters.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,003 | 0,005 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,000 |
| Méta-épidémiologie (sens large) | 0,001 | 0,000 |
| Bibliométrie | 0,002 | 0,002 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,001 | 0,001 |
| Science ouverte | 0,001 | 0,001 |
| Intégrité de la recherche | 0,001 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,002 | 0,001 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».