Concrete Coring and Cutting, Medlow Bath Station, Blue Mountains

The job

Arenco was the builder on the upgrade of Medlow Bath Station in the Blue Mountains. The job took in new stairs, a footbridge connection, new drainage along the platform and new concrete work in the ground, and all of it needed concrete coring and cutting in and around a station that stayed in use.

Perfect Concrete Care worked for Arenco from August 2023 to May 2024, coming back to site in stages as each part of the upgrade was ready for us. Our crews did the coring and cutting; Arenco built the rest.

What we did

• Concrete coring of dowel and fixing holes, starting with 48 holes at 25 mm to 300 mm deep in August 2023
• Deep cores at 125 mm diameter to 1.4 m deep, run off our own generator
• Stitch coring rows of overlapping cores to form openings through concrete in the excavations
• Saw cutting the platform surface along the marked lines for new drains and pits
• Coring precast stair flights and precast units for their fixings, and cutting at the footbridge landing
• Drilling holes for the new steel brackets on the stair structure, working from an elevated work platform where needed
• Final fixing holes at 18 mm and 24 mm in May 2024, when the diary was signed off with everything done

What made it hard

A station upgrade is not a closed site. The platform stayed open around the work, so every cut had to be fenced off, the slurry controlled and the area cleaned before the public came through. Some shifts ran at night.

The work also came in stages. Some days the crew was ready but the precast was not; one March 2024 diary records the team waiting for a precast slab to be dropped off. The job needed a crew that could come back, pick up where it left off and fit in with the builder's programme.

How it was done

Before cutting on the platform, the lines were marked out with the builder and the area was fenced. Cutting was done wet, with the slurry collected as the crew went. In the excavations, the core rig was set up on the concrete and the stitch cores were drilled in a row, each one overlapping the last, so the opening could be broken out cleanly.

For the precast stairs and units, holes were cored to the positions set out on the drawings, and every hole was checked for depth before the next one. Where the work was up on the stair and footbridge structure, the crew worked harnessed from an elevated work platform. For more on our rail work, see our rail shutdown cutting and coring page.

Lessons learned on this job

Every job teaches the crew something. These are the ones we took from Medlow Bath, and we use them on every station job.

What worked

• Bring your own power. Running deep cores off our own generator meant we did not wait on site power
• Stitch core, then break. A row of overlapping cores gives a clean opening with no hammering on the concrete that stays
• Check every hole. Measuring each core for depth before moving on meant no return visits for short holes
• Mark out with the builder. Walking the cut lines with the builder before cutting kept the platform work to the right lines

What was difficult

• A station that stays open. Every cut on the platform needed fencing, slurry control and a clean up before the public came back
• Work in stages. Days where the precast was not ready yet meant the crew had to come back later, so the programme had to allow for it
• Working at height on the structure. Drilling for the stair brackets meant harnesses and an elevated work platform, which takes more set up
• Services not always marked. On at least one shift the services near the work had not been identified, so the crew had to check before coring

If you have something similar

Builders on station upgrades need coring and cutting crews who can work around a live station and fit in with the programme. Have a look at our concrete core drilling Sydney, concrete cutting Sydney and rail shutdown cutting and coring pages, or get in touch.