Volume XV Issue 3
There are large glacial deposits present in the upper reaches of the reservoir of a large dam being proposed in northern Pakistan. Feasibility stage studies were carried out to determine the stability of these deposits once the reservoir is impounded and operated and the hazards associated with these upon failure. These studies included mapping of the glacial deposit and stability analysis of the slopes under various conditions such as after saturation, rapid draw down and under a seismic event. For slope stability analysis shear strength parameters of the glacial soils were determined through field and laboratory testing and back analysis of existing slopes. Special field tests included large-scale direct shear tests and inundation of test pits.
The results of the analysis showed that most of the glacial deposits were unstable and would fail either upon filling of the reservoir or after rapid draw down with or without associated seismic activity. The possible hazards posed by the failure of these deposits included generation of waves, local blocking of the river and increase in sedimentation. An analysis of these hazards was also carried out and it was concluded that none of these would infringe on the feasibility or safety of the project.
| Want to read the full paper? |
| To purchase a copy of this Dam Engineering paper, please email the Editor, Carrieann Davies, on: cdavies@wilmington.co.uk or fax: +44 (0) 20 8269 7804. |