Aircrete Booklet

Aircrete Booklet
2012 / 01
Introduction - What is aircrete?
The material Aircrete
Autoclaved aerated concrete (AAC, Aircrete)
Autoclaved aerated concrete
Introduction
Autoclaved aerated concrete is a versatile lightweight construction material and usually used as blocks. Compared
with normal (ie: “dense” concrete) aircrete has a low density and excellent insulation properties. The low density
is achieved by the formation of air voids to produce a cellular structure. These voids are typically 1mm - 5mm
across and give the material its characteristic appearance. Blocks typically have strengths ranging from 3-9
Nmm-2 (when tested in accordance with BS EN 771-1:2000). Densities range from about 460 to 750 kg m-3;
for comparison, medium density concrete blocks have a typical density range of 1350-1500 kg m-3 and dense
concrete blocks a range of 2300-2500 kg m-3.
Autoclaved aerated concrete blocks are excellent thermal insulators and are typically used to form the inner leaf
of a cavity wall. They are also used in the outer leaf, when they are usually rendered, and in foundations. It is
possible to construct virtually an entire house from autoclaved aerated concrete, including walls, floors - using
reinforced aircrete beams, ceilings and the roof. Autoclaved aerated concrete is easily cut to any required shape.
Aircrete also has good acoustic properties and it is durable, with good resistance to sulphate attack and to
damage by fire and frost.
Production
Autoclaved aerated concrete is cured in an autoclave - a large pressure vessel. In aircrete production the autoclave
is normally a steel tube some 3 metres in diameter and 45 metres long. Steam is fed into the autoclave at high
pressure, typically reaching a pressure of 800 kPa and a temperature of 180 °C.
Autoclaved aerated concrete can be produced using a wide range of cementitous materials, commonly:
Portland cement, lime and pulverised fuel ash (PFA) or Portland cement, lime and fine silica sand. The sand
is usually milled to achieve adequate fineness. A small amount of anhydrite or gypsum is also often added.
Autoclaved aerated concrete is quite different from dense concrete (ie: “normal concrete”) in both the way it is
produced and in the composition of the final product.
Dense concrete is typically a mixture of cement and water, often with slag or PFA, and fine and coarse aggregate.
It gains strength as the cement hydrates, reaching 50% of its final strength after perhaps about 2 days and most
of its final strength after a month. In contrast, autoclaved aerated concrete is of much lower density than dense
concrete. The chemical reactions forming the hydration products go virtually to completion during autoclaving
and so when removed from the autoclave and cooled, the blocks are ready for use.
Autoclaved aerated concrete does not contain any aggregate; all the main mix components are reactive, even
milled sand where it is used. The sand, inert when used in dense concrete, behaves as a pozzolan in the autoclave
due to the high temperature and pressure.
The autoclaved aerated concrete production process differs slightly between individual production plants but
the principles are similar. We will assume a mix that contains cement, lime and sand; these are mixed to form
a slurry. Also present in the slurry is fine aluminium powder - this is added to produce the cellular structure. The
density of the final block can be varied by changing the amount of aluminium powder in the mix. The slurry is
poured into moulds that resemble small railway wagons with drop-down sides. Over a period of several hours,
two processes occur simultaneously:
• The cement hydrates normally to produce ettringite and calcium silicate hydrates and the mix gradually
stiffens to form what is termed a “green cake“.
• The green cake rises in the mould due to the evolution of hydrogen gas formed from the reaction between
the fine aluminium particles and the alkaline liquid. These gas bubbles give the material its cellular structure.
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FIS V Resin Mortar + FIS G Rod
The anchoring system for aircrete is formed by using a combination of injection resin
mortar FISV with FIS G threaded rods, PBZ plastic sleeves and the PBB drill bit which
produces a conical hole. It is the combination of this system that holds the fixture firmly in
place and guarantees maximum load bearing capacity. Prior to installing the FIS G rod the PBZ plastic sleeve should be placed at the mouth of the
new-formed conical hole, this will ensure the rod remains in a central position.
With the PBB drill bit you are able to reach two embedment depths, varying for substrate
and load performance.
1
1
2
2
FIS V 360 S
3
3
FIS G threaded rod 4
4
PBB drill bit
Plastic sleeve
Suitability
For fixing of: Machines, gratings, gates,
handrails, brackets, pipelines, sanitary
items, cable trays etc.
Advantages / Benefits
•
•
•
•
High load bearing in aircrete.
Durable drill with long life span.
Adjustable drilling depths.
Used in conjunction with threaded rod
FIS G.
Building Materials
Blocks, slabs, wall panels, roofs and floor
slabs made from aircrete.
Certification
Injection resin mortar FISV 360 S + FIS G
Description
Installation Tips
•
•
•
•
•
•
Adjust drill to correct depth.
Drill a hole until the correct depth has been reached then rotate the drill 3 times to
create the undercut/conical shape.
Clean the hole with a blow pump to remove excess dust.
Place the plastic sleeve into the mouth of the hole and inject resin into the hole.
Position the rod into the hole through the plastic sleeve.
Apply fixture and tighten until firm.
3
Universal frame fixing FUR
Description
The FUR is a universal frame fixing. It has 29 asymmetrical close set teeth which
work in solid materials by friction locking and hollow materials by form locking. The unique
formation of teeth guarantees a high load-bearing capacity in variety of solid building
mate­rials, cavities and light weight concrete.
Suitability
Universal frame fixing FUR
Façade and roof substructures made
of wood and metal, gates, door frames,
fire protection doors, windows, kitchen
cabinets, wardrobes, squared timbers,
facings.
1
1
2
3
FUR-T - safety screw with countersunk head
2 FUR 8-SS and FUR 10-SS - safety screw with
hexagon-head
3 FUR 10 and FUR 14 F US - safety screw with
hexagon-head
Advantages / Benefits
•
•
•
•
Building Materials
Concrete, solid brick, solid sand-lime
brick, vertical perforated brick, perforated
sand-lime block, hollow block made from
lightweight concrete, no-fines lightweight
concrete, multi-layer composite concrete
wall.
Certification
Universal frame fixing.
Anchorage in solid materials by
means of friction locking.
The asymmetrical close set teeth
expand and formlock in hollow
materials.
Fixing sets with safety screws made
of stainless steel for applications in
damp conditions.
Installation Tips
▪ We advise countersunk-head screws for fixing wooden structures, and anchor sleeves with a flat collar and hexagon-head bolts for
metal structures.
▪ The hexagon-head with integral washer also has an integral  -socket.
▪ With vertical perforated bricks only use rotary drilling (no impact drilling).
4
High Performance frame fixing SXR
Description
Suitability
1
2
3
Gates, door frames, fire protection doors,
windows, kitchen cabinets, wardrobes,
squared timbers, facings façade and roof
substructures made of wood and metal,
suspended ceilings and cable trays.
1 SXR-T - with zinc-plated fischer safety screw
2 SXR-Z - with zinc-plated fischer safety screw for
Pozi-bit Gr. 4
3 SXR-FUS - with fischer hexagon safety screw of
stainless steel A4 and moulded-on washer
Advantages / Benefits
▪ The SXR has a comparatively low
tightening torque in relation to a very
high over-torque during the installation
process.
▪ This fixing has a firm, secure hold in
porous stones with large cavities.
▪ The unique geometry of the SXR means
that it can be hammered into position
without bending.
Building Materials
Concrete, solid brick, solid sand-lime brick,
perforated sand-lime brick, solid block
made of lightweight/normal weight
concrete, hollow block made from
lightweight concrete, vertically perforated
brick and thermal insulation block
Certification
High performance frame fixing SXR
The SXR is the first fischer frame fixing with an European Technical Approval. The approval
covers the classical application area to façade subframes and it regulates permissible
loads for 41 different building materials.
With an anchoring depth of 50mm it is approved for a large number of solid and
perforated building materials. New areas of application have now been opened up such
as suspended ceilings, cable trays and pipe brackets etc.
Installation Tips
▪ We advise countersunk-head screws for fixing wooden structures, and anchor sleeves
with a flat collar and hexagon-head bolts for metal structures.
▪ The hexagon-head with integral washer also has an integral  -socket.
For timber structures
For metal structures
5
Aircrete anchor GB
Description
This nylon fixing is designed specially for use in aerated concrete (aircrete). The spiral
outer ribs cut a positive fit in the aircrete. The unusual shape equates to the total diameter
of the fixing being roughly double that of the core diameter which helps achieve the best
load-bearing capacity possible.
Please note to reach the best loads possible the GB anchor must be used with the fischer
safety screw for usable lengths up to 280 mm.
1
Aircrete anchor GB
Suitability
Aircrete Anchor GB
Lamps, small wall-mounted shelves,
towel rails, lightweight mirror cabinets,
letter boxes, hanging baskets, curtain
rails, façade and roof constructions,
façade of wood and metal, suspended
ceilings and cable trays.
Advantages / Benefits
•
•
•
Simple and quick hammerset
installation reduces the work involved.
The spiral outer ribs ensures a high
grip in aircrete.
Large range of screws available for
fixing thicknesses up to 280 mm.
Building Materials
Aircrete > PB2, PP2 (G2).
Certification
Approved for the tension zone - size 14.
The approval only applies to the
combination of the aircrete fixing GB with
the fischer safety screw.
Installation Tips
▪ Drill only in a rotary motion (switch off hammer).
▪ Only suitable for use in unplastered aircrete; for use in plastered aircrete we would recommend the fischer S-H-R, FTP , FIS V.
▪ Anchor should be driven in with a lump hammer.
▪ Required screw length = fixing length + Thickness of the item being attached + 1 x screw diameter
6
Turbo Aircrete Anchor FTP K / FTP M
Description
The Turbo aircrete anchors are screwed into the drilled hole with the EK setting tool or
Hex Bit for the FTP M. The external thread carves a positive fit into the aircrete with out
applying any expansion force.
1
The nylon FTP K can be used with both metric and wood screws. The metal FTP M
however, must only be used with metric screws.
1
Suitability
Turbo aircrete anchor FTP K
(plastic)
2
Turbo aircrete anchor FTP M
(metal) Metal section, wooden battens, cable and
pipe clips, handles, gratings, brackets,
wall-mounted cupboards, sanitary ware,
lamps, letter boxes etc.
Advantages / Benefits
Building Materials
Aircrete with a compression strength of
2.5N/mm2 or more
Certification
▪ Simple and quick installation.
▪ No spalling of plastered surfaces.
▪ Anchorage free of expansion pressure
allows smaller edge distances.
Installation Tips
▪ Use a low torque when setting with a battery-operated screwdriver.
▪ Installation of FTP M is also possible with standard allen key. Size is corresponding to screw diameter, e.g. FTP M 6 is installed with
allen key size 6.
Setting tool FTP EK for FTP K
Turbo Aircrete Anchor FTP
2
Hexagonal bit for FTP M
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Universal Nylon Wall Plug UX
Description
The UX works by expansion in solid building materials and forming reliable knot
formations in cavity installations.
Use UX 6 long versions with fischer spacing screws for maximum load-bearing
capacity in perforated materials, double-skinned plasterboard and for bridging
non load-bearing layers.
1
2
1
Universal nylon wallplug UX
2
Universal plug UX
Universal plug UX-R with collar
Suitability
Picture frames, motion detectors,
lamps,skirting, electric switches, small
wall-mounted shelves, towel rails,
lightweight mirror cabinets, letter boxes,
hanging baskets and curtain rails.
Advantages / Benefits
Building Materials
Solid block made from lightweight
concrete , hollow block made from lightweight concrete and many more solid,
perforated and plasterboard substrates.
Certification
▪ The unique design enables use in almost
all building materials.
▪ The saw-tooth shaped anti-rotation locks
prevent rotation of the fixing in the drill
hole.
▪ Low-turning and high-tightening torque
▪ Can be used with wood and chipboard
screws from 4 mm to 12 mm.
▪ The collar of the UX R prevents it
slipping into the drill hole.
Installation Tips
▪ With push-through installation, use the largest possible screw diameter.
▪ Drill only in a rotary motion (switch off hammer) in perforated, hollow brick and aircrete. Use a metal bit for plasterboard.
▪ If using hook/eye screws in cavity bricks, it is essential that they have a collar, so that the screw can be tightened enough to knot the
plug completely.
▪ The required screw length is calculated by fixing length + thickness of the item being attached + 1 x screw diameter.
▪ For safety relevant applications under permanent tensile load, nylon plugs are not allowed. For example, nylon plugs must not be
used to permanently suspend lights from the ceiling.
Pre-positioned installation
Push-through installation
8
High Perfomance Wall Plug SX
Description
Plug SX / Plug SX-L
Suitability
Pictures, motion detectors, lamps, skirting,
electric switches,small wall mounted
shelves, towel rails, lightweight mirror
cabinets, letter boxes, hanging baskets
and curtain rails.
Advantages / Benefits
Building Materials
Solid block made from lightweight
concrete , hollow block made from
lightweight concrete and many more solid,
perforated and plasterboard substrates.
Certification
▪ 4-way expansion form lock
▪ Anti-rotation lugs prevent the plug
rotating in the drill hole.
▪ The special collar prevents damage of
tiles and plaster.
▪ Simple and quick push-through
installation reduces installation time.
▪ The fixings collar prevents it slipping deeper
into the drilled hole.
▪ Temperature-resistant from -40° to
+80°C.
▪ Can be used with wood and chipboard
screws between 2 and 12 mm.
High performance wallplug SX
1
The SX can be safely used with a wide range of different screw types and diameters. It is
especially suitable for chipboard screws. The plug has been designed to expand 4-ways
to ensure an unbeatable, firm grip in solid building materials.
The longer versions of SX (SX-L) are recommended for higher anchoring depths in
aircrete, perforated building materials and to bridge plaster.
The SX can be used with wood, chipboard and self-tapping screws and ASL spacing
screws.
Installation Tips
▪ Push-through installation requires the largest possible screw diameter.
▪ Drill only in a rotary motion (switch off hammer) in perforated, hollow brick and aircrete.
▪ The required screw length is calculated by fixing length + thickness of the item being attached + 1 x screw diameter.
▪ For safety relevant applications under permanent tensile load, nylon plugs are not allowed. For example, nylon plugs must not be
used to permanently suspend lights from the ceiling.
Pre-positioned installation
Push-through installation
9
Installation Examples
Solutions to a typical problem in fixing to aircrete within a disabled bathroom.
6
7
7
6
3
2
4
5
1
10
1
1
fischer resin system FIS V 360 S used in conjunction with
threaded rod FIS G, drill bit PBB and plastic sleeve PBZ
2
Frame fixing FUR
3
Universal frame fixing SXR
4
Aircrete fixing GB
5
Turbo aircrete fixing FTP
6
Universal wall plug UX
7
High Performance wall plug SX
The information in this booklet is intended for general guidance only and is given without
engagement. Additional information and advice on specific applications is available from our
Technical Services Team. For this however, we require a precise description of your particular
application.
All the data in this booklet concerning work with our fixings must be adapted to suit local
conditions and the type of materials in use.
If no detailed performance specifications are given for certain articles and types, please contact
out Technical Service Department for advice.
fischer Fixings (UK) Ltd.
Whitely Road, Wallingford, Oxon, OX10 9AT.
We cannot be held responsible for any errors and we reserve the right to make technical and
range modifications without notice.
No liability is accepted for printing errors and omissions.
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Aircrete Booklet 2012 / 01
fischer fixings (UK) Ltd.
Whitely Road
Wallingford, Oxon, OX10 9AT
Tel: 01491 827 900
Fax: 01491 827 953
www.fischer.co.uk
sales@fischer.co.uk
Aircrete Booklet . 2012 / 01 . Printed in the UK
Technical Service:
To arrange a visit from one of our Technical Field Engineers please contact the
Technical Services Department:
Phone: 01491 827 920, Fax: 01491 827950, Email: technical@fischer.co.uk
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