CLIENT
Helm Pty Ltd
LOCATION
177 Russell Avenue, Dolls Point

Our involvement

  • Geotechnical site investigation for a multi-storey building over two basements.
  • 3D numerical analyses of the shoring system using Plaxis 3D software.
  • Instrumentation and monitoring during the construction.

Project challenges

  • Presence of deep alluvial deposits.
  • Poor relative density of the upper soils and the presence of a high ground water table.
  • Presence of a four-story building at 3 m offset from the site boundary.
  • Support the excavation and limit the ground movements.

Our solutions

Due to the poor relative density of the upper soils and the presence of a high ground water table, a propped Cutter Soil Mix (CSM) wall was selected to support the excavation. To limit ground movements, one row of hydraulic props was installed at the capping beam level and stressed by jacking. One row of props, rather than two, was adopted to overcome constructability issues.

Published Paper

Theunissen. W. and Fraser, O.D. (2021). Three-Dimensional Numerical Modeling of a Propped Cutter Soil Mix Retention System in Sand.  Int. J. Geoengineering Case Histories, Vol. 6, Issue 4, p.115-151.