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Aluminium in the Building and Construction Industries - dou0824 - 2021-08-24
Aluminium in the Building and Construction Industries
Aluminium in the Building and Construction Industries
Aluminum building materials is widely used in building because of its intrinsic properties of lightness and corrosion resistance.
Aluminum is used in external facades, roofs and walls, in windows and doors, in staircases, railings, shelves, and other several applications.
Aluminium in building construction
Thanks to its features, there are many benefits that aluminum offers to the construction industry:
Alloys
Pure aluminum is a low-strength metal and consequently not suitable for building applications but thanks to the addition of alloying elements such as copper, manganese, magnesium, zinc etc. and thanks to specific production processes, it changes its physical and mechanical properties to meet requirements of a large number of applications.
Durability
Aluminum alloys for Building are resistant to water, corrosion and immune to the harmful effects of UV rays, thus ensuring a lasting endurance
Low maintenance costs
Aluminum does not require any special kind of maintenance, whether it is raw or lacquered aluminum
Finishes
Aluminum can be anodized or lacquered in any color, so it’s possible to get the most varied effects and thus meet the designer’s decorative needs. Aluminum treatments can increase the durability of the material and its corrosion resistance
Reflective properties
Aluminum is widely used for light management: its reflective properties help to reduce energy consumption for lighting and heating.
For example, it’s possible to reduce the use of air conditioning in summer season by using aluminum shielding devices.
Aluminum is not combustible
Aluminum does not burn and is therefore it’s classified as non-combustible material (A1 fire reaction class).
Nevertheless, aluminum alloys melt at about 650 ° C, but without releasing any harmful gases. And so, more and more often, the outer covers and external surfaces of industrial structures (and not) are made with thin aluminum panel finishes which are destined to merge only in case of fierce fire, thus allowing heat and smoke to escape and reducing damage Caused by the fire.
Certified studies have proved that the alloys, the surface treatments (coatings) and the materials used are all neutral. Aluminum used in the construction industry does not have any negative impacts either on the quality of the air inside buildings, on land or water.
These are just a few of the benefits of using aluminum, in a technical and technological development view the extraordinary properties of this metal will offer (potentially) endless possibilities for building engineering applications.
The aluminium element was discovered 200 years ago. After an initial period of technological development, aluminium alloys were used in many structural applications, including the civil engineering field. Aluminium is the second most widely specified metal in building after steel, and is used in all sectors from commercial building to domestic dwelling.
This paper contains complete overview of use of Aluminum corbel in building construction. How it is beneficial in modern age building construction. This paper also contains the properties, advantages. Some question arises that whether aluminium is sustainable, fabricated for fast track, requires maintenance, are explained in detail in this paper.
Aluminium is the second most widely specified metal in buildings after steel, and is used in all construction sectors, from commercial buildings to domestic dwellings. 40% of the UK annual production of aluminium is utilized within the construction industry, which equates to roughly 150,000 tonnes of aluminium per annum, of which approximately 65,000 tonnes is extruded products, and 25,000 tonnes sheet materials.
The main market sectors are windows, roofing, cladding, curtain walling and structural glazing, prefabricated buildings, architectural hardware, H&V, shop fitting and partitions. Aluminium is also used extensively in plant, ladders and scaffolding.
Primary smelter aluminium is pure and, as such, has a relatively low strength. For extrusions and other manufactured components, the material is alloyed to improve its strength, although even the most heavily alloyed wrought aluminium is still 92% pure.
The two series of alloys most widely used in construction are the 5000 series work-hardened magnesium alloys and the 6000 series heat-treatable magnesium silicone alloys. The latter are more extrudable and, therefore, offer greater scope for complex shapes. Silicone alloys (such as LM6) and manganese alloys (such as 3103) are also used for specific construction applications.
By selecting the right alloy, the designer is offered a wide range of properties including high strength (up to 400 MPa or 26 tonnes per sq inch), low density, high thermal conductivity, and good forming and joining characteristics. The choice of the most appropriate alloy of the 6000 series for a particular extrusion depends on the nature of the task it has to perform. A balance has to be struck between strength, ease of forming and finish. The 6063 alloy, for instance, has good extrudability, corrosion resistance and surface finish; and is thus widely used in fenestration. The properties of the individual alloys are amplified by the shape of the extruding die. Careful and knowledgeable design can take advantage of the ability of the extrusion process to distribute the material across the section to exactly where it is needed for a particular performance requirement.
Modern building and construction is more than merely erecting buildings as functionally as possible. In addition to functional and economic criteria, aesthetic and design considerations together with ecological demands placed on building projects play an equally important role. This means the materials used are of major significance. Aluminium, the building material for the modern age, established itself as an important factor in the building and construction industry during the course of the 20th century. Aluminium enables every possible architectural concept to be realised – regardless of whether it is a new build or a modernization. Possible applications range from fa?ades and roof and wall manufacturers of Aluminium building products systems to interior decoration and the design of living are world leaders technologically – not least space, and include windows and doors, balconies because the companies have furthered the and conservatories development of modern windows and fa?ades in the fields of surface treatment, thermal insulation and soundproofing, air conditioning and solar heating. With an annual domestic demand of about 500,000 tonnes, the building and construction industry is the second largest market for aluminium products in Germany. Its share of the total aluminium market is 15 percent.
One of Aluminium’s primary appeals to specifiers is its exceptional strength to weight ratio. At 2.7g/cm2, Aluminium is 66% lighter than steel. It is also far less susceptible to brittle fractures. Indeed, when aluminium and steel structures are compared, Aluminium’s greater modulus of elasticity means that weight ratios of 1:2 are easily attained.
While Aluminum railing has a relatively high co-efficient of linear expansion, at 24 X 10-6/’C – in its pure form, the material’s low modulus of elasticity (65,500N/mm2 for 6063 alloy) enables temperature induced stresses to be accommodated. Indeed, these are generally far lower than in a comparable steel structure (M of E = 210,000N/mm2). This is graphically illustrated by Aluminium’s load-deflection curve, which is continuous, without a yield point.
Aluminium sections are generally thinner and deeper than equivalent steel sections to achieve the required strength and rigidity since, Aluminium is not affected bymoisture and aluminium windows do not warp, stick or rot. In door construction, typically using hollow-section extrusions, sight lines are improved because multi-point locks and other door furniture can be fitted within the frame. This is in addition to the intrinsic lightness, strength and rigidity of Aluminium frames
2.2 Low maintenance – low cost-in-use
While Aluminium has a natural, built-in durability (it forms a protective layer of oxide as soon as it is exposed to air), most Aluminium construction products are treated or coated. One way in which the oxidization process can be enhanced is anodization; an electrolytic process which increases the thickness of the natural oxide layer from 0.00001mm to between 0.005 and 0.025mm (25 Microns). This enhances the ability of Aluminium to withstand attack in aggressive environments. Natural anodizing results in a similar silvery finish to oxidized Aluminium, but it can also introduce a range of colours.
This is because, after anodizing, the surface film remains porous, allowing it to accept colouring agents, such as organic dies, pigments, electrolytes or metallic. Attractive gold, bronze, gray, black and even blue finishes are commonly achieved in this way. For a wider choice of colours, most specifiers opt for an electrostatically sprayed polyester powder coating. This is a common finish for curtain walling, rainwater goods and cladding panels, where the powder coating is used to provide resistance to the acidity of rainwater. In this process, charged paint particles are blown onto the extrusion (which has undergone a twelve-stage pre-treatment process) and then stove, at between 200 and 210’C, for 10 to 12 minutes. This provides a high quality surface with excellent adhesion, accurate colouration and very even film thickness.
2.3 Fabricated for the fast track
One of the principal reasons for Aluminium’s enduring and growing popularity is its compatibility with today’s fast track construction techniques and just-in-time ordering. Nowhere is this seen more clearly than in curtain walling, where the accuracy of factory-finished sections allows rapid erection on site and, in him, allows internal finishing to proceed more quickly. The end result is earlier building occupancy and greater profit margins for the ultimate customer. Aluminium shop fronts, window systems and door assemblies offer comparable on-site benefits, which are now being enhanced by fabricators’ computer-controlled machining rigs which can drill, miter, grind and countersink to exact tolerances enabling the easiest possible installation of ironmongery, glazing beads and other secondary components.
2.4 Guaranteed performance through quality control
Although basic material costs will always be important to specifiers, they should be balanced against the cost of fabrication and subsequent service performance. This is an area where Aluminium, being ideally suited to highly automate manufacturing procedures to exact tolerances, offers many benefits. Aluminium door extrusions, for instance, are subjected to a rigorous quality regime, from hardness testing of the raw extrusion to conical bends, sawing, scratching, gouging, hammering and weight drops to guarantee coating performance. It is this combination of quality control, excellent cost in use and systems technology that has helped develop new markets for Aluminium roof companies in the health, education, leisure and transport sectors where changes in the funding of building procurement, such as PFI and fund-holding schools has changed the emphasis from lowest capital cost to lowest cost in use. Specifiers are increasingly looking for effective systems solutions by involving system suppliers early in the design process to ensure the most elegantly engineered solution at the lowest cost.
2.5 Aluminum recyclable at end of building’s life
The ability to recycle aluminum building products is also becoming more important as more building owners decide to deconstruct rather than demolish older buildings. Instead of simply going in with a wrecking ball, owners are now much more deliberate about how they take down a building in order to extract as much recyclable material as possible. By doing so, they not only retain the scrap value of a material such as aluminum but also eliminate the environmental impact and cost of dumping it in a landfill.
Aluminum recycling also reduces energy consumption. To produce aluminum from recycled material, for example, requires only 5% of the energy required to produce aluminum from bauxite. In addition, every ton of recycled aluminum saves four tons of bauxite.