GB2340530A - Aluminium kit formwork composite building system - Google Patents

Abstract

Aluminium, flanged channel sections with location and restraining detailing will be used as formwork to construct in situ walls and slabs of mainly single and two or multi-storey buildings. The walls and slabs will be of composite construction, comprised of inner and outer leaves of concrete either side of rigid sheet thermal insulation; the internal partition walls will be constructed only with the concrete material. Conduits and wall face fittings for the services will be incorporated during the construction of the concrete leaves and walls. Window and door receivers will also be included in the mould. The aluminium sections are supplied in a kit form to facilitate the complete construction of the superstructure shell, including door and window openings. When the formwork is removed and after curing the shell will be immediately ready for the installation of fittings. The surfaces need only be smoothed at joints although the exterior can be rendered and the interior painted or wallpapered without the need for plaster skims.

Description

2340530 ALUMINIUM IOT FORMWORK COMPOSITE BUILDING SYSTEM

DESCRIPTION

The invention relates to a single and low multi storey building system using a specialised aluminium kit formwork to construct the in situ concrete insulated composite walls and slabs.

The increasing world-wide requirements for good quality, economic housing which often needs to be erected quickly such as in earthquake and other disaster areas is not wholly satisfied by the currently available building systems. Each have their disadvantages of cost, unreliability, poor quality, need for skilled workers. Also the gradually rising European requirements for energy conservation and human comfort standards will make it increasingly difficult to be satisfied by traditional types of construction. Therefore innovative methods of construction will need to be considered. One such method is addressed in this presentation and involves the use of in situ cast concretes in the construction of composite walls and slabs.

At the present, in the UK the main method of construction of residential dwellings in the past few decades has been the cavity masonry wall, with more recently the inclusion of thermal insulation in the gap between the outer facing brick leaf and inner concrete block leaf in order to attain the U-value required current Building Regulations. The timber frame construction method has to a limited degree, more so in Scotland, been adopted to enable attainment of the required thermal thresholds and to facilitate speedier construction in poor weather conditions.

Although the use of in situ cast concrete has been little used in UK, such as in the 'No Fines Whimpey System', it is extensively used on the continent. For example in France and other European countries, concrete is extensively used either as in situ cast or as precast units in a wide variety of building types but generally not the small domestic dwellings where blockwork is still favoured, either of the clay or concrete types. The present described system overcomes all of the disadvantages of the existing methods.

1 Aluminium flanged channel formwork comes in kit form to produce the complete building shuttering system. The extruded aluminium sections are produced in various widths, limited by minimisation of face deflection under loading by the wet concrete and these may be flanged channel box sections of extruded widths from 100 min up to 300 mm. Wider sections are produced by combination of welded narrower sections. A range of section lengths will be available from greater than 2.0 m, to shorter lengths to facilitate the inclusion of window and door openings.

Horizontal beams are assembled to provide a base for the vertical sections of the wall formwork. The sections have detailing to facilitate precise and easy erection. The Base Beams and Elevation Panels are illustrated in Figures 1 to 5. Each section is sufficiently lightweight to be easily manhandled and no crane or other plant will be essential for erection. A composite wall or slab, containing one or more of the materials of dense concrete, rigid sheet thermal insulation or recycled rubber composite sheet material and foamed concrete. In isolated regions of third world countries, equivalent alternative materials such as fibre reinforced clay mud may be used.

The system is exemplified by detailing the constriction of a small building, as illustrated in Figures 7 and 8 which show respectively the assembled external wall kit for this typical small building and its flat roof or ceiling/dormer accommodation floor assembled aluminium formwork. The elevations or outside walls of the building are comprised of an outer leaf of 100 nim or more thick dense concrete, adhering to rigid sheet thermal insulating material which is in intimate contact with the inner leaf of 100 min or more thick concrete. The single storey building cross section is shown in Figure 9.

The positioning of the thermal insulation layer during the casting of the concrete is ensured by the inclusion of the Spacing Beam of the design illustrated in Figure 6. The partition or internal walls are constructed of the concrete layer only. The solid ground floor, upper floor of a two storey structure and flat roof or loft floor where a pitched roof is to be added are of dense concrete construction. Where required the thermal insulation layer is to be included and a screed topping of the foamed concrete or similar. The ground floor will incorporate the insulation and screed, the upper floor the screed only and the flat roof the thermal insulation with a weather proof finish.

2 The programme of construction would be as follows.

A reinforced concrete floating slab foundation is provided with accurate dimensioning and levelling ascertained by inclusion of the Base beams formwork system. This system creates a platform to receive the aluminium Plan beam formwork, laid out to the building and room plan.

The ground floor level vertical formwork kit outer skin is erected, creating a box section of the building. They are joined together and so are self supporting and restrained in all directions.

The Spacing beams are placed at designated positions, providing resting for the insulation sheeting.

The sheets of insulation material (insulation sheets 2.6 m x 0.6 m), with grooved edges are set in place and glued together to create a full wall sheet.

The internal kit formwork is erected in place, including the two faces of the partition walls. Ducting and conduits for services are placed within the formwork, being temporarily held in place, secured to the formwork.

Door and window openings are included in all wall sections where required with window receivers included within the formwork system. Lintels will be incorporated above the openings by placing steel cages on top of the opening formwork.

The horizontal upper floor kit formwork is placed, forming a slab and resting on the internal wall formwork. Steel mesh is then laid across the entire area.

The concrete is then pump poured for the internal partition and inner leaf walls of the entire single storey structure but not including the outer skin wall The Spacing beams are removed and the void between the outer formwork and the insulation sheeting is pumped full of concrete.

The horizontal section of the formwork is then concreted, thus completing the moulding of the unit in one operation.

After initial curing, all formwork is removed and the shell is now immediately ready for door and window fittings, etc. Surfaces do not essentially require plaster finishes but need only be rubbed smooth at formwork joints. However if desired, the wall surfaces are ready to receive any texturing or decorative finishes such as wallpaper.

A second storey or greater can also be added, while fitting work proceeds on the ground floor, once the concrete has gained adequate strength.

3 Figure Titles Figure 1 Slab Beam Internal Web Figure 2 Slab Beam Top Flange Figure 3 Slab Beam Bottom Flange Figure 4 Elevation Panel Web Figure 5 Elevation Panel Top or Bottom Flange Figure 6 Spacing Beam Figure 7 Assembled Shuttering Panels of Elevation Outer Leaf Figure 8 Assembled Shuttering Panels of Flat Roof Figure 9 Cross Section View of Completed Single Storey Building, with Shuttering Removed and Annotation Key I Aluminium Channel Section 2 Hole for Collar Nut D = 20 nun 3 Typical Hole for Erection, Alignment and Bolting Fittings 4 Stiffening Plate 5 Aluminium T-Section 6 Double Elbow Type Hinge 7 Pulling Cord 8 Locking Mechanism 9 Pulling Knob 10 Full Height Shutter Panel 11 Short Panel Below Window opening 12 Base Beam 13 Panels Laid Horizontally 14 Wall Shuttering Panels Cut in Horizontal Section 15 Typical Construction of Wall: 100 mm Concrete Outer Leaf, 50 mm Thermal Insulation, 100 mm Concrete Inner Leaf 16 Composite Horizontal Roof/Ceiling 17 Composite Vertical Wall Element 18 Reinforced Concrete Floating Slab Foundation 4

Claims (8)

1. A building construction formwork/shuttering kit system, comprised of a number of reusable, modified sections of extruded aluminium, which are assembled manually on site to accommodate the three dimensional requirements of the building design, ready to receive the infill materials, normally concretes, and removed after curing to provide the full superstructure unit with smooth surface finish.

2. In the system described in Claim 1, between the outer and inner shuttering assemblies, thermal insulation boards, window receivers, door receivers and conduits and wall fittings for electric, water and other services such as ventilation, security and telecommunications, where required, are installed within the shuttering during assembly of the kit formwork.

3. 'llie assembled system defined in Claims 1 and 2 is stabilised, restrained and aligned by screws, bolts and by its own stiffening system created by the specific design of the modifications to the extruded aluminium sections.

4. The modifications to the extruded aluminium sections of width in the region of 350 min, referred to above in Claim 3, involve holes for levelling, alignment and securing bolts, and stiffening plates, which are basic horizontal and vertical elements of the kit.

5. The Spacing Beam is part of the kit, manufactured using an extruded aluminium Tsection, and is designed as a double elbow joint for the purpose of accornmodating its removal during the concrete pouring procedures.

6. The Spacing Beam referred to in Claim 5 supports the insulation material, when present, when the insulation board acts as a temporary shutter for the pouring of the inner wall leaf concrete of the vertical elevations and is then removed prior to the pouring of the remaining concrete of the structure.

7. The kit sections of Claims 4, 5 and 6 are provided in lengths to the requirement of the unit walls and horizontal roof or ceiling dimensions and to accommodate openings.

8. A shuttering/formwork system as claimed in the preceding Claims include for use in construction of entire dwelling units, as well as any other construction situation requiring in situ casting of concrete.