Construction is underway for a new 8-storey mixed-use waterfront development at Port Melbourne in Victoria, on the site of the 150-year-old former London Hotel. Current construction work follows the complex but successful shoring and excavation of the site’s two level basement structure earlier this year.
On completion, the new 92 Beach Street development will feature basement parking, three floors of mixed retail and 18 luxury residential apartments.
Poor soil conditions and other site constraints presented a range of design challenges for the project team.
The presence of Coode Island Silt – a soft soil notoriously found around inner Melbourne – required special design considerations. This rich and highly compressible type of silty clay can be complex to excavate, given its potential for settlement; the possibility of oxidation when groundwater is removed; and the occasional occurrence of gas pockets.
Combined with high groundwater levels, a tight 800sqm waterfront site and adjacent basement structures, these challenging conditions excluded the use of temporary ground anchors to support excavation. Instead, a highly bespoke temporary works solution was required.
Throughout 14 months of detailed design, Coates Engineering Solutions worked as part of a project team alongside Crema Group’s Camillo Builders; civil contractor Delta Group; geotechnical engineer Golder; Wagstaff Piling; and structural engineer Webber Design. In July 2020, this team successfully delivered an internal hydraulic strut propping solution for this complex excavation.
The London Hotel’s two level shoring solution incorporates a 500 thick reinforced piled concrete diaphragm wall surrounding the basement structure, supported by a robust internal hydraulic strut propping arrangement.
Mega Brace Beams – Coates Hire’s proprietary hydraulic strutting system – were used to achieve maximum load bearing capacity. For the strength of steel and the convenience of hydraulic adjustment, MP150 and MP250 struts were also used – each measuring 610mm in diameter and rated to 150T and 250T.
This modular solution ensured clear spans for easy access to the excavation site and easy installation – both vital given the compact nature of the site.
As well as supplying all hire equipment, Coates Engineering Solutions contributed to the temporary works design, provided all engineering drawings, design certification and on site supervision through a qualified and experienced engineer.
“The diverse support we were able to offer to the client helped to create project efficiencies and foster confidence in the overall solution,” says Joe Hovanjec, National Projects Engineer, Coates Engineering Solutions. “The fact that a bespoke structural steel solution of this scale could be hired, rather than purchased and scrapped, provided additional cost savings for the client.”
According to Dominic McCarthy, Camillo Builders Senior Project Manager, the basement excavation for The London Hotel was a particularly complicated dig. “Having Coates Solutions on the team ensured a high quality solution could be achieved,” says Dominic. Their involvement also allowed us to deliver a cost effective and efficient temporary works solution, setting this project up for success.”
The final shoring solution enabled the safe, efficient and timely excavation of The London Hotel site’s foundation and two level basement structure, and allowed for construction work to commence. This project is due for completion in mid 2021.
SHARE THIS ARTICLE
By submitting this enquiry you agree to Coates's Communications Terms & Conditions