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Telescopic Beam Connection

BSF 300 kN, Beam-Column connection

USP

  • Corbel-free connection for beam-to-column and beam-to-beam applications
  • Maximum vertical load capacity of 300 kN
  • Fast and safe installation with the steel knife retracted during erection
  • Clean architectural finish with no visible supporting corbels
  • Suitable for round and other non-standard column geometries
  • Documented design guidance, reinforcement details and calculation tools

BSF 300 is a telescopic steel connection developed for transferring heavy vertical loads from precast concrete beams to columns, walls or other beams. The system eliminates traditional concrete corbels and creates a clean, unobstructed connection with a smooth soffit.

The connector is suitable for both beam-to-column and beam-to-beam applications. It has a maximum vertical load capacity of 300 kN, a minimum column width of 280 mm and a minimum beam dimension of 190 x 420 mm.

Function and Design

The BSF 300 system consists of three main components: a beam unit cast into the supported beam, a column or beam-to-beam receiving unit cast into the supporting element, and a solid steel sliding knife that transfers the load between the units.

During erection, the knife is retracted and protected inside the beam unit. Once the beam is correctly positioned, the knife is extended into the receiving unit. The load is then transferred through the steel knife and into the specified anchoring reinforcement in the precast elements.

Materials and Finish

The main load-bearing components of the BSF 300, including the blade and semi-circular bearing plates, are manufactured from S355 steel, with grade 8.8 threaded rods. The recess boxes are manufactured from thin sheet steel and supplied in standard finish.

Applications

BSF 300 is designed for heavy-duty connections between precast beams and columns, beams and walls, or two beams. The corbel-free arrangement is particularly useful where architectural appearance, clear headroom, efficient formwork and flexible column geometry are important.

Installation and Fire Performance

The telescopic design supports fast and safe erection because the knife remains inside the beam unit until the beam is in position. After installation, the connection can be protected by the surrounding concrete and completed in accordance with the project-specific fire-protection design. The steel components have reaction to fire Class A1 according to EN 13501-1.

Documentation and Design

Technical memos cover capacities, main dimensions, reference levels, tolerances, torsion, expansion joints, seismic design proposals, reinforcement design and installation guidance. A dedicated BSF calculation tool is also available for structural design.

BSF products are manufactured under CE-marked production in accordance with EN 1090. The declared BSF 300 vertical load capacity is 300 kN, based on minimum concrete strength class C35/45 and project-specific reinforcement design.

Design and reinforcement must be verified for the actual beam, supporting element, loads, tolerances and project conditions using the current technical documentation.

Maximum vertical ULS load
300 kN
Fire resistance with 25 mm concrete cover
R60
Minimum column width
280 mm
Minimum beam width
190 mm
Minimum beam height
420 mm
Steel knife material
S 355
Half-round steel and steel plate
S 355
S 300, kniv
17 kg
B 300, bjelkeenhet
8 kg
SF 300, søyleenhet
4.3 kg
Anchorage reinforcement. Steel grade 500C shall be used
Ø 12 and Ø 16 mm
Threaded bars to carry forces RHO and RHU. Bars are grade 8.8 steel
M12 and M16
Minimum concrete grade
C35/45

  • BSF 300 k N søyle bjelke tegning
    BSF 300 k N søyle bjelke tegning