SH20 to Airport – Manukau, Auckland

SecuGrid® – Multi Directional Geogrid

Contractor

MHX Kirkbride Alliance

Sub-Contractor

Fletcher Infrastructure & Higgins

Engineer

Beca and Fletcher Construction Co (FCC) temporary works engineers

Client

NZTA


grant-suckling

Grant Suckling

Technical Sales

linkedin-reps

SH20A is the primary route to and from Auckland Airport and forms a strategic link between SH20 & SH16, the Airport Business District and the greater Auckland area. The NZ Transport Agency’s upgrade of SH20A to motorway standard has provided a safer, more reliable route to and from the airport and has increased freight efficiency around South Auckland.

DESIGN

Cirtex worked with FCC temporary works engineers to design working platforms over very weak ground conditions for the safe operation of heavy machinery. Cirtex also provided an alternative slope stability solution, saving significant time and money.

INSTALLATION

Two layers of SecuGrid were used to reinforce the gravel raft providing efficient load distribution of the stresses transferred from the heavy plant and equipment. As an alternative to sheet piling Platipus Anchors were used in conjunction with CombiGrid to stabilise steep cuts.

The products used provided the following benefits to the project:

  • Platipus provided an anchor system that was cost effective in comparison to other systems
  • CombiGrid and Platipus anchors were chosen to stabilise steep cuts as they used readily available equipment for installation
  • SecuGrid assisted in providing an efficient and safe working platform

Products used in this project

SecuGrid® Multi-Directional Geogrid

SecuGrid is designed to interlock with the aggregate placed above it to provide stabilisation and bearing capacity improvement to soft subgrades and also reduce rutting in a pavement application.

Platipus® Civil Anchor Systems

Platipus percussion driven mechanical anchors are a unique, modern and versatile device that can be rapidly installed in to most displaceable ground conditions.

CombiGrid® Multi-Directional Geogrid Geotextile Composite

CombiGrid combines all the functions of a geogrid and geotextile in one single product and is ideal for reducing aggregate depth requirements and providing a stable platform on soft ground.

DuraForce™ AS Series Nonwoven Geotextile

DuraForce AS series geotextiles are manufactured and tested to exact quality standards and rated according to the NZTA F/7 specification for geotextiles. Available in a range of grades depending on the particular engineering application required.

Related case studies

View All

Plunket Ave Enabling Works – DuraForce™ & SecuGrid®

10 Feb 2016

During the development of the Plunket Avenue Manukau site into an industrial park, the developers faced the challenge of very soft subgrades, large industrial buildings and tight...

Read more

Montreal Business Park – SecuGrid®

10 Feb 2016

The engineer selected SecuGrid® 40/40 due to its high modulus and low elongation. SecuGrid 40/40 was placed in 4 layers through a 1.2m deep aggregate foundation and allowed compaction of the...

Read more

Auckland Airport Runway – DuraForce™ AS Geotextile

10 Feb 2016

DuraForce™ AS410 nonwoven geotextile was used on this major infrastructure project at Auckland International Airport. Contractors Fulton Hogan were excavating for this high load pavement area...

Read more