EFFECTS OF TUNNELLING ON THE BEARING CAPACITY OF SHALLOW FOUNDATIONS

Anna-Maria Zakhem, Hany El Naggar

In the proceedings of: GeoQuébec 2015: 68th Canadian Geotechnical Conference & 7th Canadian Permafrost Conference

Session: Foundations I / Fondations I

ABSTRACT: Urban tunnelling can induce distortion to the existing three-dimensional stress regime due to the development of ground arching and the associated stress redistribution. In some cases this may decrease the bearing capacity of nearby foundations which could cause damage to the overlying structures especially in soft soils and/or densely populated areas. Thus, the effect of tunneling on the performance and capacity of nearby foundations may be significant and should be considered in their design. This paper uses the finite element method with an elastic-plastic model and the Plaxis 3D software to study this interaction problem considering a number of parameters such as the tunnelling processes, construction sequence, proximity, and the burial depth. Accordingly, recommendations for the design of shallow foundations in close vicinity to shallow tunnels were proposed.

RÉSUMÉ: Le creusement de tunnels urbains peut induire une distorsion du régime de contrainte tridimensionnel en raison du développement d™une voûte et de la redistribution des contraintes associées. Dans certains cas, cela peut diminuer la capacité portante des fondations proches qui pourraient causer des dommages aux structures en surface, en particulier dans les sols mous et/ou les zones densément peuplées. Ainsi, l'effet des tunnels sur la performance et la capacité des fondations à proximité peut être important et doit être pris en compte dans leur conception. Ce document utilise la méthode des éléments finis avec un modèle élasto-plastique et le logiciel Plaxis 3D pour étudier ce problème d'interaction en examinant un certain nombre de paramètres, tels que les processus de creusement, la séquence de construction, la proximité et la profondeur d™enfouissement. En conséquence, des recommandations pour la conception des fondations superficielles à proximité immédiate de tunnels peu profonds ont été proposées.

Access this article:
Canadian Geotechnical Society members can access to this article, along with all other Canadian Geotechnical Conference proceedings, in the Member Area. Conference proceedings are also available in many libraries.

Cite this article:
Anna-Maria Zakhem; Hany El Naggar (2015) EFFECTS OF TUNNELLING ON THE BEARING CAPACITY OF SHALLOW FOUNDATIONS in GEO2015. Ottawa, Ontario: Canadian Geotechnical Society.

@article{042,author = Anna-Maria Zakhem; Hany El Naggar,title = EFFECTS OF TUNNELLING ON THE BEARING CAPACITY OF SHALLOW FOUNDATIONS,year = 2015}