Rock Face Cutting and Coring, Arthur Street, North Sydney

The job

Shotcrete Australia has been the head contractor on a rock face stabilisation job along Arthur Street in North Sydney, cutting and coring pockets and niches into a natural sandstone retaining wall that runs beside a busy public road.

Perfect Concrete Care has been the on call cutting and coring crew on this job since July 2023, coming back to site as new sections of the wall were released for work. This page covers the job through to November 2024, a stretch of around seventeen months.

What we did

• Concrete and rock cutting to form pockets and niches into the sandstone face, following the lines set out for each section
• Coring through sections of the rock and hourly works as each new area was released
• Core samples pulled from the rock face, measured and labelled with test codes for the lab
• Working from a boom lift to reach sections of the wall well above street level
• Traffic control and site signage set up before any plant started, and taken down after
• Hourly works and call outs as new sections of the wall came up over the life of the job

What made it hard

This was a live road, not a closed site. Every visit meant setting up traffic control and signing off the work area before a single cut went in, and packing it all away again once the crew was done for the night. Most of the cutting was done at night, when the road could be managed safely and the boom lift could get in close to the wall.

The rock itself was not uniform. Natural sandstone strata meant every pocket cut a little differently to the last, and weather played its part too, with the crew standing down on at least one occasion for rain and again waiting on a panel delivery before work could continue. Being an on call job over such a long stretch also meant remobilising cleanly each time, often months apart, without losing time getting back up to speed.

How it was done

Each visit started with the road signed and fenced before the boom lift or any cutting gear was set up. Sections of the wall were cut and cored to the lines needed for the pockets and niches, working up the rock face from the lift basket.

Core samples were pulled as the job required, checked against the tape and marked up with their test codes before being sent off. Once a section was finished for the night, the crew packed down, cleared the road and reopened it, ready to come back for the next release of work.

Lessons learned on this job

Every job teaches the crew something. These are the ones we took from Arthur Street, and we use them on every on call job on a live road.

What worked

• Sign and fence before anything starts. Getting the traffic control right first meant every night on site started clean and safe
• Work at night when the road allows it. Night works kept the road managed and gave the boom lift clear access to the wall
• Label samples as they come out. Marking cores with their test codes on site meant nothing got mixed up before testing
• Pack down properly every time. Clearing the road fully at the end of each visit kept the relationship with the client and the road authority straightforward over seventeen months

What was difficult

• Rock that was not uniform. Natural sandstone strata meant every pocket needed its own read before cutting
• Weather and deliveries. Rain and a wait on a panel delivery both cost the crew time on separate visits
• A long on call stretch. Coming back to the same job months apart meant getting back up to speed quickly each time
• Working over a live road the whole time. There was no closing Arthur Street down around the job

If you have something similar

Head contractors needing an on call cutting and coring crew for rock face or retaining wall work on a live road should have a look at our concrete cutting Sydney and concrete core drilling Sydney pages, or get in touch.