A flimu coupler (also called a flimu anchor), developed by Dywidag, is a mechanical connection that permanently joins individual reinforcement bars in a concrete structure — a full alternative to lapping bars over a length. Instead of placing two bars alongside each other over a calculated distance, the bar ends are connected directly through a coupling sleeve.
Application
In reinforced concrete, the reinforcement bars must transfer forces between one another. Traditionally this is done by lapping: two bars run side by side over a calculated length, passing the forces through the surrounding concrete. This method uses extra steel and, in densely reinforced areas, causes a build-up of bars that makes the concrete harder to pour and compact.
A flimu coupler solves this by joining the bars mechanically. It is especially useful:
- For large numbers of couplings — eliminating the lap length saves a significant amount of steel and weight.
- At corners and bends in the reinforcement — such as floor-to-wall connections, where bars change direction and lapping is awkward to place.
- In dense reinforcement cages — the coupler reduces the amount of steel at any one point, so the concrete can flow and compact properly.
- In phased construction — the coupler provides a reliable connection point for reinforcement that is added in a later pour.
The result is a connection that transfers tensile forces just as well as a continuous bar, with predictable strength and a cleaner, more buildable structure.
Related terms
- Reinforcement
- Concrete
- Foundation
- Lapping
- Reinforced concrete
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