Hanson Building Products
Omnia and Cobiax
FLOORING SYSTEMS
Omnia and Cobiax
FLOORING SYSTEMS
Omnia
System overview
4
Benefits
5
Construction details
6-7
Bearing details
8
Temporary support
9
Cobiaxdeck
System overview
10
Benefits
11
Design and construction
Nationwide service
2
12-13
14
The Omnia system from Hanson Building
Products is a pre-cast floor panel that
provides the direct equivalent of an in-situ
slab but provides the facility to combine
pre-cast and in-situ concrete.
Cobiaxdeck is a development that combines
the advantages of Omnia wideslab flooring
with Cobiax void forming technology to
create a long-spanning, biaxial deck system
without beams.
The Omnia flooring system is equally
suitable for steel and concrete framed
structures and masonry buildings
Omnia
All Omnia products incorporate the
triangular Omnia lattice girder that is
attached to a lower layer of
reinforcement before wet concrete
is poured to create the Omnia panel.
Cobiaxdeck
The system displaces non-working
deadload through the incorporation of
hollow spheres between the upper and
lower layers of reinforcement.
3
Omnia
SYSTEM OVERVIEW
The Omnia system provides major benefits over alternatives
when used as fully participating permanent formwork.
The basic Omnia product is the
Omnidec panel which incorporates
the distinctive triangular Omnia
lattice girder, manufactured from
cold drawn steel wire with
a characteristic strength of
500 kN/mm2.
The Omnia girder is attached to an
individually designed lower layer of
reinforcement and wet concrete is then
poured to create the Omnidec panel.
The triangular lattice girder provides
the panel with its stiffness during the
temporary condition and ensures a
mechanical bond between the precast and in-situ concrete.
It also serves to provide support for
the upper mesh reinforcement
(supplied by the contractor) and is
used as the anchor point when lifting
panels into position on site.
Each Omnidec panel is designed
and manufactured to order, each
with its own specific shape and
structural capacity.
Unlike pre-stressed concrete flooring
systems, Omnidec panels are wetcast into pre-formed shapes that butt
joint together on site.
4
Omnia benefits
Structural strengths
Can be designed to withstand most loading conditions
Can be designed to cope with rigorous exposure conditions
Where Omnia
can be used
The Omnia system is suitable for use on
steel and concrete framed structures as
well as masonry structures
Can be designed to protect against fire for long periods
Each panel is designed to suit its specific location
Progressive collapse conditions economically provided
Fast installation
Large panels mean less lifts
Commercial and Industrial
Panels are lifted into place without the need for slings
Hotels, factories, warehouses and
retail structures
Large areas of floor can be erected in a short space
of time
Design flexibility
Irregular and complex shapes manufactured to suit
contract requirements
Service holes and cut-outs accurately formed during
manufacture
Smooth flat soffit can take direct decoration and top
surface can be power-floated reducing depth of
overall floor zone
Public buildings
Hospitals, schools, fire and police
stations, prisons.
Exposed soffit can be used to provide ‘thermal-mass’
Competitively priced
System costs compare favourably with those of
traditional formwork
Decorated soffit can be left exposed, negating
suspended ceilings
Residential
Low and high rise apartment blocks,
student accommodation blocks, hostels etc
In-situ topping can be power-floated negating extra
finishing screed
Quality service
Factory-manufactured to consistent quality standards
Car Parks
Complies with all relevant standards
Single level or multi-story complete
with ramps
5
Omnia
CONSTRUCTION DETAILS
Dimensions
Each Omnia panel is designed and
manufactured to suit its location.
Sizes are, therefore, infinitely variable.
By increasing the amount, size and
height of the lattice girders, the panels
can be made to span great lengths
without temporary propping.
Panels are cast onto 50m long beds
accurately set and split into individual
panel lengths.
Each panel is designed to cope with
its specific loading condition and is
reinforced with bars from 8 to 16mm
placed at 50 to 300mm centres.
The beds are 2.40m wide which
determines the maximum width of
panel. However, every contract may
have a proportion of non-standard widths.
Tolerance
For standard 2.40m wide panels, the
width is controlled and the dimension
is virtually exact.
For non-standard panel widths with
formed edges and at the bearing ends,
the panels are cast within the
tolerances allowed, usually to ±10mm.
Panel depths
The precast concrete panels can be
provided at 50, 60 and 75mm as
required by the structure’s specific fire
and exposure conditions.
Constituents
The Omnia lattice girders are cast into
the precast concrete panel at centres
from 480mm down to 150mm to
provide stability in the temporary
condition.
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With over 11 million permutations of
lattice girder, steel reinforcement and
concrete available, it is possible to
cope with the most onerous of loading
and exposure requirements.
Maximum Spans
The maximum span of any Omnia
panel is a result of a number of factors
including the span/depth ratio,
temporary condition requirements,
preferred method of propping
(if allowed).
Spans of up to 14m are possible,
subject to satisfying deflection criteria,
but the normal maximum panel length
is approx. 11.0m. Hanson’s Omnia
design team can provide designs at
tender stage to determine the most
cost-effective span/depth ratio.
Appearance and shape
All Omnia panels are cast to length on
steel moulds. Long edges are formed
with a chamfer to the underside so
that, when placed adjacent to each
other, the effect of a bird’s mouth joint
can be seen at regular intervals on the
soffit.
Holes for services etc. can be neatly
cast into the panels during manufacture.
Special side forms are introduced at
casting stage enabling panels to be
produced to suit the shape of the
building and it is, therefore, possible to
cater for structures with complex floor
layouts.
Ends of panels are formed with square
forms to provide a suitable surface at
the lines of bearing.
Soffit quality
The steel moulds used for casting ensure
a high quality finish suitable for direct
decoration with paint or textured finish.
As no pre-stressing wires are used in
the manufacture of the Omnia panels,
the soffit is also flat with no camber.
All products in the Omnia system utilise the Omnia lattice girder, reinforcing
steel and dense concrete. Omnidec is the basis for the product range with
variations and accessories as shown below:-
Omnidec
A precast concrete panel reinforced
with steel bars and incorporating the
Omnia lattice girder to provide
strength in the temporary condition
(i.e. during erection). Reinforced
in-situ concrete is placed over the
panel to create a solid concrete
homogeneous slab.
Typically used for spans from 1.0m
up to 6.50m, providing slab depths
from 135mm to 250mm, at which
point Omnicore should be
considered to reduce overall dead
weight on the structure.
However, on civil engineering
structures, slab depths occasionally
exceed 750mm. Slabs can also be
cast using lightweight aggregate to
reduce self-weight.
The Omnicore variation
Similar to Omnidec except that in
between the lattice girders, lengths
of polystyrene are cast into the top
of the precast section to reduce the
amount of in-situ required and
therefore the weight of the
completed slab.
Typically used for spans of 6.00m
and over, providing slab depths from
250mm upwards.
Reductions of 20 - 25% in slab
weight can be expected.
Accessories
Omniedge
Omnitherm
Omniedge is a galvanised steel edge
shutter cast into the edges of the
precast panels at the factory.
Omnitherm is produced by fixing
an insulation board to the soffit of
the panel during casting.
Generally it is used on masonry
structures and is a competitive
method of providing an edge shutter
to the completed slab.
This can significantly enhance the
thermal insulation value of the
concrete floor slab.
7
Omnia
BEARING DETAILS
Omnia panels are suitable for use on concrete and
steel framed structures and on masonry buildings.
Bearing on steelwork
Panels require a nominal bearing
of 55mm.
Panels bearing at differential levels may
require a compressible bitumenised strip
to prevent point bearing and excessive
grout loss.
Shelf angles must be of such a length as
to allow the end of the panel to pass the
top flange during placing, and be set at a
height that will allow continuity.
Bearing on in-situ concrete
Support panels on the formwork and cast
a fully homogeneous slab.
The OMNIA preferred option.
When supported on ‘half-cast’ beams,
links must be so arranged to allow
55mm nominal bearing.
Where less than 55mm bearing is
available, a suitable temporary prop must
be in place before placing the panel and
left in place until the in-situ portion has
reached working strength.
Bearing on masonry
Panels are usually detailed to take the
full bearing of the internal skin of masonry,
allowing the use of ‘Omniedge’ edge
formwork (see page 7).
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Two OMNIA panels can be supported on
140mm wide load bearing blockwork
with a 20mm gap between.
Where less than 55mm bearing is available
eg. on 100mm walls, temporary props should
be in place prior to placing the panels.
Construction
TEMPORARY SUPPORT
The greater the stiffness of the panel,
the greater the distance it will span
without propping.
The stiffness is as a result of the
‘Moment of Inertia’ created by the
lattice girder.
The value of the ‘Moment of Inertia’ is a
result of a combination of lattice height,
lattice top bar diameter and the number of
lattice girders cast into the panels.
Spans up to 4.0m regardless of slab depth
will generally be designed to be erected
without props.
Depending on the depth of the slab, spans
of over 6m can be designed to be erected
without propping and spans over 7m can
be designed to be erected ‘post-propped’
(see below). Please check with Hanson for
maximum spans using Omnicore, as the
introduction of the polystyrene limits the ability
of the panel to span with reduced propping.
Unpropped
No props are required, except for localised supports around openings etc.
These will be identified on the Omnia layout drawings.
Overall
slab depth
Maximum
unpropped span
150mm
3.95m
175mm
4.40m
200mm
4.85m
225mm
5.40m
250mm
6.10m
Overall
slab depth
Maximum
post-propped span
150mm
5.80m
175mm
6.80m
200mm
7.00m
225mm
7.20m
250mm
7.50m
Post-propped
Continuous head timber
Prop
One row of props
placed mid-span
Panels are self-supporting, but will require one row of props placed mid-span
prior to placing materials, particularly the in-situ concrete.
Propped
Props are typically spaced at 2.50m
centres, although these centres can be
extended to suit the contractors
requirements.
Panel lowered onto supports
Examples are spans in
the 7m – 11m range.
OMNIA panels can also be designed
to cope with the loads transferred
from temporary props, thereby
eliminating the need for
‘back-propping’ on lower floors.
2.50m Max
Temporary props shall remain in position in
accordance with the requirements of the
relevant code of practice, and whilst their
spacing will be shown on the Omnia panel
layout drawings, the actual design of the
props will be responsibility of others.
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Cobiaxdeck
SYSTEM OVERVIEW
Cobiaxdeck combines the established
advantages of the Omnia system with
spherical void forming technology to
enable the construction of light weight,
biaxial floor slabs with column grids
ranging from 6m up to 18m without
beams.
The resultant overall slab depth will be
determined by the arrangement and spacing
of the columns as well as the ultimate loading.
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The combination of these technologies
allows the construction of buildings with
wide open spaces, providing for greater
flexibility with internal design.
The use of void forming technology
reduces the volume of concrete in the
floor slab by displacing non-working
deadload.
The absence of beams also means a
reduction in the overall floor zone which,
in some instances, can allow space for
the construction of an additional floor.
The reduced weight can impact on the
design and reduce the cost of
foundations and the system is ideal for
use where ground conditions are poor
or piling is required.
Cobiaxdeck benefits
Biaxial design
No need for support beams
Reduced structural zone
Where
Cobiaxdeck
can be used
Suitable for all types of buildings but is
ideal for larger scale projects including:
Resource effective
Fewer columns
Wide open spaces
Greater design flexibility
Reduced costs
Faster build
Shopping centres
and supermarkets
Reduced in-situ concrete
Foundations
Lighter weight slabs means reduced costs for foundations
Ideal for poor ground conditions or piling
Thermal performance
Design allows thermal mass to be exploited
Office complexes and
high-rise commercial buildings
Lower heating/cooling costs
Quality service
Factory produced quality
Complies with all relevant standards
Schools and universities
Hospitals
Hotels
Apartment blocks
Industrial buildings
Multi-story car parks
11
Cobiaxdeck
DESIGN & CONSTRUCTION
Conventional construction
Cobiaxdeck construction
Additional Space
Structural
principles
Cobiaxdeck provides the potential for
savings on materials, floor depth, slab
weight, foundations and build-time if
incorporated at the design stage of the
contract.
The Cobiax system of biaxial design in
conjunction with the void forming
system allows for a considerable
reduction in the volume and weight of
the slab without compromising this
ability to maintain biaxial strength.
The Cobiaxdeck system provides a very
cost-effective alternative to achieve the
required deflection criteria in long span
applications.
Less excavation
Absence of beams in the Cobiaxdeck
structure offers the potential for an
additional floor (or floors).
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Weight savings impact on floor slabs,
vertical elements and foundation
design, effectively reducing costs.
Hollow spheres, manufactured from
recycled polyethylene, are used as void
formers. They are held in place, relative
to the soffit and to each other, in
lightweight steel cages.
The utilisation of the spheres provides
weight saving of between 20-30%
compared to an equivalent solid
concrete slab.
The extremely efficient biaxial design can
also enable savings to be made on the
weight of reinforcement required for the
ultimate loads on the floor slab, as well as
the size of columns and foundations
saving up to 50% structural concrete.
The Dry-Method is the name given to
the system where the precast panel is
sent to site for placing without the Ball
and Cage matrix attached. Only one layer
of reinforcement is included in the
precast panel.
The precast panels include
2 layers of reinforcement.
Soffit quality
Dry-Method
The 2nd layer of bottom steel and the
shear connector bars are laid into
position on top of the precast panel.
The Ball and Cage assemblies are sent
to site separately and are placed in
position. The top steel is then placed and
tied down to the lattice girder to prevent
‘floating’.
The In Situ-Method is the name given
to the system where the voided biaxial
slab is created on traditional formwork
with no precast concrete involved.
Wet-Method
If the Cobiaxdeck option includes a
precast Omnia element, this is cast on
smooth flat steel casting beds giving
a first class soffit ready for direct
decoration.
Thermal mass
The thermal mass in a Cobiaxdeck slab
can significantly reduce the energy
requirement of the building once in use.
This can be achieved passively, through
solar gain and night cooling, or actively
through the use of fluid circulation where
reduction figures of up to 66% of the
energy needed to heat and cool the
building have been achieved.
Sustainability
The panels are placed onto prepared
falsework, splice bars are threaded
into place and shear connectors
laced around the columns to pre-set
shear ladders already cast into the
panels.
The top layers of reinforcement are
then placed across the whole of the
assembly before concreting.
Cobiaxdeck is a solutions driven system
and Hanson’s engineering team work
with the client throughout each project to
maximise the benefits and achieve an
ideal solution.
Hanson provide a full design service
including all aspects of the biaxial
construction, panel and loose
reinforcement layout drawings for all
3 options.
Cobiaxdeck
options
The Wet-Method is the name given to
the system where the ball and cage
matrices are fully bonded to the
reinforced precast concrete at the factory.
Design
In Situ-Method
The void forming technology and the
absence of beams in the structure,
combined with the reduction in the
number of support columns required,
reduces the volume of the concrete used
in the building effectively reducing the
CO2 omissions produced during the
manufacturing process.
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Nationwide
SERVICE
The Floors and Precast Division of Hanson Building Products now
operates from a total of six dedicated plants located throughout the UK.
A specialist design facility for all
Omnia systems is located at
Washington, Tyne and Wear.
Manufacture of Omnia products is
undertaken at a dedicated facility
at Alfreton, Derbyshire.
Other precast concrete
products
Jetfloor
Beam and Block
Staircases
Hollowcore
Standards
All products are manufactured in
accordance with relevant British/
European/Trade Association Standards.
All Hanson Building Products sites are
quality assured to BS EN ISO9001 2000
We operate environmental
management systems at all our
production sites in accordance with
the methodology set out in the
BS EN ISO14001 2004.
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Omnia bridgedeck
Culverts
Bespoke solutions
For Omnia and Cobiaxdeck
solutions please contact us at:
Hanson Building Products
Wilden Road
Pattinson South Industrial Estate
District 8, Washington
Tyne & Wear, UK,
NE38 8QB.
Tel: 0191 417 0066
Fax: 0191 417 0131
Email: [email protected]
Washington
Hanson Building Products
Floors and precast locations
Omnia production
Hoveringham
Derby
Ipswich
Somercotes
Tytherington
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Omnia Brochure (Final Artwork):-
22/6/09
14:51
Hanson Building Products
Head Office
Stewartby
Bedford
MK43 9LZ
Page 2
Floors and Precast Division
0870 6097094
Tel: 08705 258258
Website: www.hanson.com/uk
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OM 01 | April 2009
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