FREQUENTLY ASKED QUESTIONS

Tunnel formwork is a steel formwork system that forms the shear walls and the floor slab of a reinforced concrete structure in the same pour. Two half tunnels are set facing each other; the gap between them forms the wall and the upper surface forms the slab. Two separate operations finish as one, and the storey cycle shortens considerably.

On a well-organised site the storey cycle is 1–2 days. The governing factor is how long the concrete takes to reach stripping strength: 12–16 hours in summer, 24–48 hours unheated in winter. Without planned heated covers, a 24-hour cycle will not hold through winter.

The economics depend on repetition. Where the same floor plan repeats at least 60–100 times (mass housing, dormitories, hotels, barracks) tunnel formwork comes out ahead. For one-off buildings, or where every floor differs, panel formwork suits better.

Most of the price is steel tonnage, and tonnage is set by fresh concrete pressure, slab thickness and span. On top of that come the mechanism (screw jacks or hydraulic), surface treatment, platform and handrail equipment, and engineering. A price per square metre without the project dimensions is guesswork.

Typical floor plan and storey height, wall and slab thicknesses, number of blocks and storeys, target storey cycle, crane capacity on site, concrete class and consistency, and the casting season. From these, the number of sets and piece weights are worked out together.

St 37 (S235) or St 52 (S355), per project. The body and panels are generally St 37; lifting lugs, anchor plates and load-concentrated connections are St 52. Because both grades share the same modulus of elasticity, panel flatness is solved by section size and stiffener spacing, not by grade.

To DIN 18218. The inputs are pour rate (m/hour), concrete consistency class and concrete temperature. Where self-compacting concrete (SCC) is used, the calculation assumes hydrostatic pressure. Panel plate, stiffening profiles and tie spacing are selected for that pressure.

A maintained steel mould gives hundreds, and in some groups thousands of cycles. Service life depends less on the steel grade than on cleaning after every pour, the right amount of release agent and regular checks of moving parts.

Yes. First erection is carried out on site by our team, with handover training for the user crew. Technical support on stripping, maintenance and spare parts continues afterwards.

Yes. Where the layout changes, existing formwork is adapted to the new geometry. The load on the new section is recalculated; panels are reinforced or dimensions changed with filler pieces as required.

We work on a sales basis; formwork is designed and manufactured for your project and delivered to you.

Yes. We manufacture moulds in more than thirty product groups, including beams (rectangular, I, L, LT), columns, slabs, battery moulds, wall panels, stairs, culverts, barriers, kerbs, gullies, channels, sleepers and tetrapods.

It depends on the type and tonnage of the mould and on the current production load. Once dimensions and quantities are settled, the schedule is agreed and stated in the quotation.

Yes, we manufacture for projects abroad. Shipment planning and loading are organised by us.