[en] This paper numerically examines the bearing capacity and failure mechanism of a shallow strip foundation constructed above twin voids. The voids may refer to caves, caverns, underground aqueduct or tunnels due to water seepage, chemical reaction or deliberately excavated in soil deposit. The ability of numerical model to accurately predict the system behavior is evaluated by performing verification analyses on existing researches. Subsequently, a parametric study carried out to reveal the influence of size of footing/voids and their location (i.e. depth, spacing, eccentricity) on the bearing capacity of footing. To clarify the failure mechanism, the distribution of shear strain in the soil for different scenarios is assessed. The parametric study provided a new framework to determine the bearing capacity and the mode of failure for footings on voids. Based on the results, a criterion can be issued to avoid collapse of footing/voids regarding the shape, location and size of voids. The results can also be used to design construction of a footing on existing voids while the acquired failure mechanisms can be appointed to develop analytical solutions for this problem. Results demonstrated that a critical depth for voids and a critical distance between them exist where the influence on the ultimate bearing capacity of footing disappears.
Disciplines :
Civil engineering
Author, co-author :
ALIMARDANI LAVASAN, Arash ; University of Luxembourg > Faculty of Science, Technology and Medicine (FSTM) > Department of Engineering (DoE)
Talsaz, Ali; Faculty of Civil Engineering, K. N. Toosi University of Technology, Tehran, Iran
Ghazavi, Mahmoud; Faculty of Civil Engineering, K. N. Toosi University of Technology, Tehran, Iran
Schanz, Tom; Chair of Foundation Engineering, Soil and Rock Mechanics, Faculty of Civil and Environmental Engineering, Ruhr-University Bochum, Bochum, Germany
Alexander von Humboldt-Stiftung (DE) Deutsche Forschungsgemeinschaft
Funding text :
The first author gratefully acknowledge the financial support provided by Alexander von Humboldt Foundation (Germany) through the postdoc research scholarship. This research has been supported in part by the German Research Foundation (DFG) through the collaborative research center (SFB 837).
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