The project ‘The Imperial’ consisted of an intricate excavation procedure in which conventional piling and anchoring was prohibited due to the development’s proximity to the RailCorp corridor. As per RailCorp guidelines, anchoring beneath the railway tracks is strictly prohibited to prevent rail tracks displacement.

Therefore, Alliance Project Group successfully coordinated the design and implementation of an alternative system to anchoring.

Alliance Project Group’s senior management team managed the design of a complex network of steel circular hollow section struts, spanning 25 metres in length. This complex strut system was utilised to support an 18 by 100 metre shoring barrier, directly adjacent to the RailCorp corridor.

In collaboration with ACE consulting, MYD consulting, Asset geotechnical and RailCorpauthorities, a sequencing procedure was developed in accordance with RailCorp guidelines, outlining an effective excavation method to minimise the temporary displacement of RailCorp assets. The strict implementation of this procedure was executed by ACE demolition and excavation and thoroughly supervised by Alliance Project Group, through the use of a multitude of monitoring devices, ensuring the overall displacement of RailCorp assets remains within the maximum displacement limit of 4 mm.

Due to the site logistics, numerous enabling procedures were developed in order to create a more streamlined excavation process. This involved the creation of a temporary platform constructed for the purpose of utilising a long reach excavator due to the site constraints in which the excavation line was directly adjacent to neighbouring buildings and other infrastructure.

Additionally, due to the access difficulties within the site, discussions took place with Hurstville City Council where an agreement was reached to lease Council’s land and utilise it for construction vehicle transport. Moreover, the excavation was further complicated due to the various essential services that passed within the site. These included the main sewer and stormwater line within the Hurstville catchment area and hence temporary diversions were required to be both designed and implemented.

Alliance Project Group has successfully finalised the implementation of this strutting system, with super-structure works currently at podium level. Poised to reach a height of 16 storeys, The Imperial development, featuring commercial tenancies and a blend of one, two & three bedroom luxury apartments, will add a significant high-rise presence and elegance to Hurstville.

Watch a time-lapse of the basement excavation for Imperial, Hurstville.