ComFlor
51 is a traditional dovetail re-entrant
composite floor deck. This profile provides an
excellent mechanical key into the concrete slab,
offering a strong shear bond performance, which
is augmented by cross stiffeners located in the
profile trough. ComFlor 51 presents a virtually
flat soffit and a relatively thin slab is required
to meet fire design requirements.
Shear studs
The wide trough of ComFlor 51 permits a flexible
and efficient placement of shear studs.
Fire performance
of the composite beams
Even for two hours fire rating, the top flange
of the steel beam does not require fire protection,
when used with ComFlor 51 composite deck.
Under floor services
Services are easy to attach to ComFlor 51, with
the ribs presenting a dovetailed recessed groove
in the concrete slab at 152.5 mm centres. This
provides the perfect connection for service hangars
via a wedge nut or similar type device.
Fire performance
of the slab
The dovetail presents a very small opening and
contributes little to the transfer of heat through
the slab in the event of fire. Thus a lesser slab
depth is needed for fire design purposes.
Deck material
Zinc coated steel to BS EN 10147:1992,
Fe E 350G, Z275, with a guaranteed minimum yield
stress of 350 N/mm2. Minimum zinc coating mass
is 275 g/m2 total including both sides.
Quick reference tables
The quick reference load/span and fire design
tables, on the following two pages are intended
as a guide for initial design, based on the parameters
stated below the tables (for full details
click
here).
Anti-crack mesh
BS 5950: Part 4 currently recommends that anti-crack
mesh should comprise 0.1% of slab area. The Eurocode
4 recommendation is that anti-crack mesh should
comprise 0.2% of slab area for unpropped spans
and 0.4% of slab area for propped spans. Panels
and Profiles, in conjunction with The Steel Construction
Institute, has agreed to modify the requirement
with regard to anti-crack mesh, to comply with
the Eurocode 4 recommendations. Accordingly, the
mesh shown in the quick reference tables complies
with EC4 and the design program defaults to these
values. Where EC4 mesh rules are used, the mesh
may be reduced midspan. The reduced British Standard
mesh values may still be used by overriding this
default in the design program. Mesh top cover
must be a minimum of 15 mm, and a maximum of 30
mm. Mesh laps are to be 300 mm for A142 mesh and
400 mm for A193, A252 & A393 mesh.