IN-SITU GEOTECHNICAL INVESTIGATION OF A CONFINED SEDIMENT DISPOSAL FACILITY, SYDNEY HARBOUR, NOVA SCOTIA

摘要

During the winter of 2011-2012, 4.2 million cubic meters of material was dredged from the navigation channel of Sydney Harbour. 3.8 million Cubic meters of this sediment was used to construct a Confined Disposal Facility (CDF) on the western shore of Sydney Harbour's South Arm. In October 2012 and July 2013, two surveys utilizing the portable free-fall penetrometer Nimrod were undertaken to investigate the sediment dynamics of the Harbour and evaluate the stability of recently deposited dredged sediments at the CDF and throughout the channel. The results of these two surveys showed a consistent trend of consolidation of the dredge material and a decrease in the thickness of the potentially mobile sediment top layers. In addition to the marked decrease in the top layer thickness (TLT), slumping of newly deposited dredged sediment from the near-shore, toward the mid-channel, was observed.