The analysis follows the specifications in the standard AS 3600-2009 clause 9.2, but the major part of the design is based on the research presented by F K Lim and B V Rangan. Please note that AS 3600 does not have a specific clause on shear stud design. Therefore the software is based on a research paper. We strongly recommend the shear stud design is verified against an alternate standard, such as BS 8110 or BS EN 1992, Eurocode 2.
The shear capacity of the slab is checked against the design shear forces at the critical shear perimeter (refer to AS 3600-2009 for further details on determining the critical shear perimeter) and if required Shearfix studs are designed to increase the shear capacity of the slab.
The first stud is positioned 0.5d from the face of the column, with the spacing between individual studs taken at 0.7 (D - top cover - bottom cover - 5) with a maximum limit of 500mm. The Shearfix Program designs the rails, firstly at 0.7 (D - top cover - bottom cover - 5) and then checks the shear capacity of the slab. If the shear capacity of the slab is still below the design shear force, the program will then reduce the spacing until the shear capacity of the slab exceeds the design shear force.
The maximum spacing between parallel rails is 600mm or D whichever is less.
If more than one rail is required for each side of the column, rails should be placed at the corner of the column in the torsion strip.
A check is carried out for over reinforcement - if this check fails, a warning message states that failure due to punching shear is possible and an increase in slab thickness will be required.
Click the link to download the calculation method used in the Ancon design program (Lim and Rangan).
Shearfix Calculation Method (PDF, 34.7 KB)
Effect of Slab Penetrations
Where there are openings in the slab within 2.5b0 (b0 = width of an opening) from the critical shear perimeter (cl. 188.8.131.52), a section of the slab will be ineffective and the critical shear perimeter will need to be reduced. The Ancon design program allows reductions to be applied to the critical shear perimeter as appropriate.
Other Design Codes
In addition to AS3600, the Ancon program enables design of a Shearfix system to BS 8110 and BS EN 1992, Eurocode 2.
Ancon are pleased to confirm that we are now Platinum members of the Concrete Institute of Australia in support of their mission to promote and develop excellence in concrete research, technology, application, design and construction.
Ancon has extended its range of reinforcing bar couplers and accompanying technical information offered to the local concrete industry in Australia.