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BSF Beam and Column Connectors Specification

Traditionally, concrete beams were supported on columns using integral corbels. Apart from being difficult and costly to form in the column, they reduce headroom locally and spoil the appearance.

Using BSF connectors eliminates the need for corbels, leaving a smooth soffit. Round, or odd-shaped columns present no problems. For heavy loads from beams into columns, walls or other beams, the BSF system should be used. They consist of three-part telescopic connectors, but are otherwise similar in application principle to the range of telescopic stair landing connectors.

BSF BB (beam to beam) and BSF BC (beam to column) connectors are designed for heavy-duty beam supports, with capacities from 225–1100kN. By using pairs of connectors, loads up to 1400kN can be catered for.

Product reference

  • [BSF 225] – Capacity: 225kN.
  • [BSF 300] – Capacity: 300kN.
  • [BSF 450] – Capacity: 450kN.
  • [BSF 700] – Capacity: 700kN.
  • [BSF 1100] – Capacity: 1100kN.

Steel finish

  • Plain.

 

Guidance for BSF Beam Connectors

  • As standard.

Material

  • Steel (grade S355, minimum).

 

Concrete strength class

  • C35/45, minimum.

 

Reaction to fire

  • Class A1, according to EN 13501-1.

We were thinking how we could give the architect what they wanted: a finished landing with a shadow gap all around. We used the telescopic connection system from Invisible Connections, which made it a lot easier, both to install the wall recesses and to install the stairs.

Ali Solki, Project Engineer, A J Morrisroe 
Ali Solki, Project Engineer, A J Morrisroe

I’ve used your services on my last three projects (telescopic connectors for precast and continuity strip for in-situ). You’re very good at accommodating site demands for lead-in times and value competitiveness. Very happy with the service I’ve received on all three projects and hope this relationship will continue on future developments.

Paul Dean, Project Manager (Qcf), JP Dunn Construction Ltd 
Paul Dean, Project Manager (Qcf), JP Dunn Construction Ltd

Telescopic connectors provide us numerous advantages for precast stair installation. Apart from improved time and efficiency, the health and safety gains over traditional support methods are a key driver to satisfy our own needs, as well as those of our clients.

Shane Dunleavy, Project Manager, Morrisroe 
Shane Dunleavy, Project Manager, Morrisroe

As specialists in precast concrete car park construction, we use telescopic connectors for many key applications. Particularly, the BSF system helps us to construct a ‘modern’ frame without cumbersome corbel supports and enables rapid assembly on site. The technical back-up provided by Invisible Connections provides us with added reassurance.

Peter Crofts, Precast Design Manager, SCC Design Build Ltd 
Peter Crofts, Precast Design Manager, SCC Design Build Ltd

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