Abstract
The catastrophic earthquake of 7.6 magnitude on Richter scale hit Northern Pakistan on October 8th 2005 at 084955 PST. The yellow earthquake drill was performed immediately after the earthquake to investigate the effects of this earthquake on the different structures of the Tarbela dam. The earthquake drill comprising of hydrographic survey, monitoring of all the instruments, physical inspection of the major structures, movement survey, and comparisons of seepage. The data indicates changes in the seepage pattern and pore pressures before and after earthquake. The pore pressures rise upstream as well as downstream of grout curtain was observed. The maximum seepage increase up to 1.11 cfs in RDA-22 and drainage adit discharge from l827 to 1913.64 gallons per minute were recorded. No significant change, movement or settlement of expansion joints were observed, however displacement of a retaining wall 13 to 14 mm at the top of' a retaining wall at construction joint was recorded. Minor movement of top set slope and deposition of sediments in front of tunnels have also been found. Long term monitoring to study the effects in depth such as micro fracturing of the structures, seepage at right abutment and allied problems is suggested to ensure the safety of the dam. /Mohammad. Saleem Khan, Mian Ali Gul, Muhammad Mushtaq, and Ghulam Muhammad. Determination of immediate and long term effects of Earthquake-2005 on Tarbela Dam, Pakistan. Life Sci J 2012;9(3):221-225] (ISSN: 1097-8135). http://www.lifesciencesite.com. 33