Wagstaff Piling was contracted by Hanssen to construct the retention system for the precinct development of the site in Applecross. Future use of the precinct includes three multi-story residential towers built in stages, with the basement retaining works completed for the whole precinct in the first phase for the tower known as ‘Sabina’ Wagstaff Piling constructed the basement retaining wall using 800mm and 600mm thick diaphragm walls due to the high water table on the site and the depth of the excavations for three basements. The total length of the diaphragm wall was 450 lineal meters. The diaphragm wall rig used was a Kobelco BMS 800 duty cycle crane equipped with a Casagrande KRC2 grab. The project was particularly challenging as a result of the sloping site levels and access for large piling equipment on staged benches. The varying geotechnical conditions across the length of the site where clay layers were not present required a cut of wall to delineate the first phase of the works and to facilitate an environmentally acceptable de-watering strategy. Barrettes were utilised by the client for the tower core foundations making use of the equipment already on the site.
