Open Collections

The influence of impermeable cores on the seismic behaviour of earth dams

University of British Columbia

The influence of an impermeable clay core on the static and dynamic behaviour of an earth dam is investigated. The cores used are of two types, central core and upstream sloping core. Recommendations are made on the suitability of each type of core for dams in areas subject, to seismic activity. The finite element method of analysis is used and the material is assumed to behave in a viscoelastic manner. The sloping core dam is found to be less desirable than the central core dam for earthquake regions because of the unfavourable stress distributions in the upper part of the dam. Static tensile stresses develop in this region, which do not occur in the central core dam, and the extent of these stresses is increased when the dynamic stresses due to the earthquake are superimposed. The accelerations, which increase with elevation in the dam, indicating the necessity of using a variable seismic coefficient, are higher in the sloping core dam than in the central core dam. It is found that the first mode, the only mode that approximates a shear mode, contributes the major share to the dynamic response of the dam. The finite element method is shown to be sensitive to irregularities in the subdivision of the dam into finite elements.

Text

2011-06-08

For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.

http://hdl.handle.net/2429/35307

Civil Engineering

University of British Columbia

Graduate