ENGR. M. IBRAHIM SAMOON - Dams Engineer ACE Pakistan, a member of the team of Safety Inspection and Design of Remedial Works for the dam and dykes of Jatiluhur Dam Project, Indonesia

Applying basic soil mechanics concepts a method has been developed to compute the settlement-time history of an earth core rockfill dam. The method utilises consolidation characteristics of core material and effective stress changes in core due to reservoir variations. The method was applied to explain the settlement mechanism of the 108 m high Jatiluhur dam, located in West Java, Indonesia which continues to settle even after 45 years of construction. The settlement rate of the dam is accelerated during events of major reservoir drawdown. The results of consolidation tests on undisturbed samples from core and water level records of Jatiluhur reservoir spanning more than four decades were utilized to calculate the settlement-time history. A very close match was observed between the actual and calculated values. The method even explains the minor as well as major kinks in the observed timesettlement curve when reservoir level drops.

analysis, consolidation, dam, earth-rockfill, embankment, settlement, theoretical