Sumner Road
anchoring

Project Description

HGM Construction was contracted to carry out anchoring work on two retaining walls as part of the Sumner Road Reopening Project following damage incurred in the 2010-2011 Canterbury Earthquakes.

As an essential haulage route between Lyttelton and Christchurch, the retaining walls formed an essential part of the enabling work to allow the road to be strengthened and reinstated. The scope included drilling, anchor installation, grouting and testing of GRP anchors up to 12 m deep across the two retaining wall sites.

Project Challenges

The key challenge for this project was access, with a steep drop off below the road down to the quarry. HGM worked with Hunter Civil to design a safe work system that allowed work to be carried out on scaffold without the requirement for rope access.

The remote-controlled excavator mounted drill rig setup was decided to be the best option for under reaching the anchors from the road and allowing sufficient maneuverability to reach the required anchor locations and angles. Controlling the rig via remote allowed the driller to be removed from the excavator for safety and to retain good visibility of the holes being drilled.

Another challenge for this project was working on a dynamic, large scale site with multiple Contractors working at the same time across various areas along the road including scaling and blasting taking place on the cliffs above the road. A high level of coordination and management had to take place to ensure the safety of everyone on site and there were times where drilling work had to be halted to ensure that rockfall risk from work on the cliff above could be suitably mitigated to allow our work to safely continue. Coordination was also required with the quarry below which was operational while this project was being completed.

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Location

Sumner Road, Lyttleton

Client

Hunter Civil Ltd

Date

2017

Excavator-mounted construction drill working beside a rocky roadside slope during civil construction and drilling services. The image shows civil contractors carrying out rock anchors, soil nails, slope retention and ground stabilisation on a constrained road site.

Civil construction and drilling services underway on a steep coastal hillside, with an excavator-mounted construction drill installing rock anchors above the harbour. This image highlights slope retention, ground stabilisation, site construction and complex construction projects managed by civil contractors.

Erosion control matting installed along a rural track as part of walking track construction and civil construction works. The image shows civil contractors completing siteworks, ground stabilisation and recreation construction in an exposed natural landscape.

Civil construction and drilling services underway on a steep coastal road, with an excavator-mounted construction drill completing rock anchors for slope retention above the harbour. The image shows civil contractors managing ground stabilisation, site construction and complex construction projects in a constrained hillside environment.

Panoramic view of civil contractors completing anchoring and piling works on a narrow coastal road, with excavation equipment positioned beside safety fencing and harbour views. This image highlights retaining walls, slope retention, rock anchors, site preparation and project management for a challenging civil construction site.

Excavator and construction drill set up on a narrow hillside road for civil construction, slope retention and ground stabilisation works. The image shows civil contractors carrying out drilling services, rock anchors and siteworks above the coastline.

Construction drill operating on a steep coastal slope during civil construction and anchoring works, with excavation equipment supporting drilling services above the harbour. This image shows civil contractors completing rock anchors, soil nails, slope retention and ground stabilisation on a difficult access site.

Civil contractor standing beside a construction drill during rock anchor installation on a steep coastal road above the harbour. The image highlights drilling services, anchoring and piling, slope retention, ground stabilisation and site construction for a complex construction project.

Drilling services and rock anchor installation taking place on a hillside construction site, with civil contractors working beside an excavator-mounted construction drill. This image shows slope retention, ground stabilisation, anchoring and piling, and civil construction above a coastal landscape.

Wide view of civil construction on a narrow coastal road, with excavation equipment, safety fencing and civil contractors preparing for slope retention works. The image highlights site preparation, rock anchors, ground stabilisation and project management on a complex hillside construction site.

Panoramic image of an excavator-mounted construction drill working beside a harbour road during civil construction and anchoring works. This image shows civil contractors delivering drilling services, rock anchors, soil nails, slope retention and ground stabilisation in a coastal environment.

Civil contractor monitoring a construction drill during rock anchor installation on a steep coastal site above the harbour. The image shows drilling services, anchoring and piling, slope retention, soil nails and ground stabilisation as part of a complex civil construction project.

Excavator-mounted construction drill working against a rocky roadside slope, with civil contractors supervising drilling services for slope retention and ground stabilisation. This image highlights rock anchors, soil nails, retaining walls preparation and civil construction on a constrained coastal road.

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