Client name: Stride Holdings Limited

Duration: October 2013 – October 2015

Location: Massey, Auckland, New Zealand

Coffey provided timely advice to manage ground risk and cost on our client’s Northwest Shopping Centre Development in Auckland’s new Westgate Town Centre. 

Situation

The 6.2 hectare Northwest Shopping Centre Development is a new addition to the fast developing suburb of Massey in Auckland’s north-west. It’s seen as the corner stone of the town centre, which when complete will include a supermarket, large department store, food court, specialty retail, a civic centre and a town square.

We were engaged to provide certainty in the construction tendering process – carrying out a geotechnical investigation of sufficient detail for tendering and design purposes.

As part of the development we also provided geotechnical analysis and design input for a four metre high retaining wall along the edge of the busy Hobsonville Road. 

Solution

A comprehensive geotechnical investigation was conducted in consultation with the structural engineer and main contractor. Hand auger boreholes, machine boreholes and CPT testing ensured a thorough understanding of ground conditions for tendering and design purposes.

Collaboration with the structural, civil and hydraulic consultants during the design of the retaining walls and building foundations aided in optimisation of pile sizes, depths, retaining wall requirements, carpark pavement design and subsoil drainage requirements. Our analysis of likely settlement profiles for shallow pad versus pile building foundations provided cost and program savings, and mitigated the risk of unacceptable differential settlement of the building.

During construction we monitored foundation construction and identified key geotechnical risks. Our regular inspection of pile and pad foundation excavations and confirmation of soil strengths ensured structures were in line with the development’s geotechnical design parameters. And our timely advice meant construction delays were minimised and the project remained on track for completion.

Result

Our detailed investigation and design input on the retaining wall and foundation design, in collaboration with the other design consultants, optimised the foundation design – managing geotechnical risk and ensuring timely and cost effective project completion.