Stop Losing Time at the Joint: Improving Productivity, Safety and Cost Certainty with Permanent Formwork
Construction joints in tunnelling projects can appear straightforward on drawings. In practice, the way they are delivered on site can influence programme sequencing, safety exposure and installed cost outcomes on underground infrastructure projects.
If you have ever watched a tunnel crew wait for shutters to be stripped, joint faces roughened, and formwork rehandled in a congested underground environment, you will recognise the issue. These activities often sit on the critical path and typically involve manual handling in confined spaces. With the right construction approach, many of these activities can be reduced or removed.
That is where Stremaform® permanent formwork, comes in – a system increasingly used on underground projects to simplify construction joint formation and reduce activities on the critical path.
The hidden cost of ‘business as usual’
Traditional construction joint methods require a predictable sequence: pour concrete, wait for it to cure, strip the formwork, dust-generating preparation of the joint face, then begin setting up for the next pour. Each step demands labour, equipment, and critically, time.
These constraints are often most acute in underground environments, where access is restricted, working space is tight, reinforcement densities are high, and multiple trades are competing for the same confined area at the same time.
The result? Pour cycles slow down. Labour costs increase. Safety exposure increases. And the programme float is often consumed in areas assumed to be routine.
A smarter approach to joint formation
Stremaform®, developed by Max Frank and supplied in Australia by Silva Global, is a steel permanent formwork system designed specifically for reinforced concrete construction joints. It is installed at the pour break and stays in place permanently, forming a clean, accurate joint face with an integrated mechanical interlock.
What does that mean in practice? No stripping. No roughening. No rehandling of shutters.
Each Stremaform® panel is designed and fabricated to suit your project’s specific geometry and reinforcement layouts. That level of precision is essential underground, where tolerances are tight and getting things right the first time is not optional. It is a commercial necessity
Where it makes the biggest difference
Permanent formwork delivers value wherever traditional joint methods create bottlenecks. On tunnelling projects, the highest-impact applications include:
Base slab transverse joints. Staged slab construction means multiple construction joints. With Stremaform®, downtime between pours can be significantly reduced and shutter striking is eliminated entirely, allowing works on the critical path to be completed faster.
Wall-to-wall interfaces. In caverns, shafts, and portal structures, wall-to-wall joints are often characterised by high rebar densities and restricted access. Permanent formwork provides a defined, repeatable joint interface without adding to the congestion.
Wall-to-slab interfaces. Where base slabs are constructed ahead of walls, Stremaform® creates a permanent joint face at the slab pour stage. Forming the wall can then proceed without delay, a significant advantage when programme pressure is high.
Cross passages and localised widenings. Complex geometry and confined access in these areas can increase safety risk and the cost of conventional joint formwork. Permanent formwork simplifies the process and reduces the number of activities required in tight spaces.
TBM-driven projects with cavern zones. Where road-headers excavate enlarged sections outside the TBM envelope, cast-in-place concrete with multiple joints is common. Stremaform® supports efficient, repeatable joint construction in these high-demand environments.
More than just a formwork solution
What sets Stremaform® apart from a simple product substitution is the level of integration it enables. The system can incorporate integrated waterstops, crack control detailing, and movement or expansion joint configurations, all within a single, coordinated joint solution.
That means fewer secondary joint treatments, fewer follow-on trades, and fewer interfaces to manage at each pour break. For project teams managing complex underground works, this consolidation of scope is where real programme and commercial gains are found.
Max Frank’s local engineering team works with project teams early in the design process to coordinate joint layout, performance requirements, and reinforcement detailing. Whether Stremaform® is tied into site-fixed reinforcement or secured to prefabricated cages, the system is designed to suit your construction methodology, not the other way around.
Silva Global supplies Stremaform® permanent formwork and works with tunnelling project teams across Australia to improve productivity, safety, and commercial outcomes at construction joints.
Talk to us today to find out how Stremaform can add value to your project.
