MAIN SOUTH RAILWAY LINE - EMBANKMENT REMEDIATION

A large landslip occurred on a steep fill embankment slope near Port Chalmers as a result of heavy rainfall in June 2015. The landslip undermined land adjacent to the railway track above, with debris inundating downslope land and impacting buildings.

GeoSolve were tasked with providing a remedial design to restore the rail line to full operation. Our engineers carried out site investigations and explored several solutions, working closely with the client and the contractor to develop a remedial solution. Ultimately a reinforced earth embankment and rockfill buttress was adopted as the preferred solution.

Interim stability of the rail line was provided by driven earth anchors until construction of the embankment was completed.

Key Project Challenges

• Developing a solution which allowed the track to remain open during the design and construction phases

• Challenging work site, construction sequencing and access constraints