Designing Buildings - The Construction Wiki

Search

Subjects

Tools / info

Edit this article

Last edited 14 Feb 2023

Structural metal

Metals are solid material that are generally hard, shiny, malleable, fusible, ductile, and have good electrical and thermal conductivity. Metals are commonly used in the construction industry due to their durability and strength to form structural components, pipework, cladding materials and other components.

Within the context of the built environment , the term ‘structure’ refers to anything that is constructed or built from different interrelated parts with a fixed location on the ground. This includes complete items such as buildings, and parts of items, such as arches. However, in relation to the use of structural metals it generally refers to a body of connected parts that is designed to bear loads.

The first use of metal in the structure of buildings can be traced back to ancient civilisation such as the Egyptians, who used copper to reinforce the masonry walls of their temples and palaces. However, the use of metal in structural applications was limited until the development of iron in the early 2nd millennium BCE.

Iron was used extensively by the Hittites and Assyrians, in the construction of large structures, such as fortifications, bridges, and aqueducts. The use of iron in building construction continued to evolve, with the development of steel in the 19th century enabling the construction of larger and more complex structures, such as skyscrapers and suspension bridges.

Today, the use of structural metal, including steel, aluminium, and other alloys, is common in construction, in particular for large-scale and complex structures due to its strength, durability, and flexibility.

Structural steel, for example, has a high tensile strength, which means it can withstand large stresses without breaking or deforming. This makes it ideal for use in high-rise buildings, bridges, and other large structures that must withstand significant loading. Structural aluminium, while not as strong as steel, is also known for its durability and corrosion resistance, making it a popular choice for outdoor structures.

Another advantage of using structural metal in construction is its flexibility. Steel and aluminium can be easily moulded into a variety of shapes and sizes. This versatility allows architects and engineers to design and build structures with unique shapes and features, while still maintaining the strength and durability needed to ensure their safety and stability.

Structural metal is also relatively easy to work with and instal. Steel and aluminium are both relatively lightweight compared to some other building materials and can be easily transported to the site, where they can be cut and shaped or installed to fit the specific needs of the project. This makes the construction process faster and more efficient, reducing the overall time and cost of the project.

The production and transportation of steel and aluminium can result in significant greenhouse gas emissions. However, advances in technology and production processes have led to more sustainable practices, reducing the environmental impact of structural metal production.

Several types of structural metal are, or have been, commonly used in building construction, including:

Steel: The most commonly used metal in construction. It is strong, durable, and widely available. It is used in a variety of structural applications, including beams, columns, frames and so on.
Aluminium: Known for its light weight, corrosion resistance, and ease of fabrication. It is often used in structural applications that require a high strength-to-weight ratio, such as in the construction of lightweight bridges and towers.
Cast Iron: A strong, durable metal that was often used historically for its load-bearing properties in the construction of buildings and bridges.
Reinforcing steel, also known as rebar: A type of structural steel used to reinforce concrete structures, such as foundations, columns, and walls.
Stainless steel: A corrosion-resistant metal that is often used in building construction for its aesthetic appeal and durability. Stainless steel contains a high proportion of alloy elements such as chromium, which generally do not form rust on their surfaces and do not discolour at normal atmosphere.
Galvanised steel: A coating of zinc prevents corrosive substances from reaching the base metal. The zinc also acts as a sacrificial anode, meaning that if the coating is scratched, the remaining zinc will still protect the exposed steel.
Wrought iron: A very low carbon metal made by intensive hand work using small scale production methods. Predominantly, it was manufactured prior to the Patent for the Bessemer process in 1856.
Alloys: ‘Impure’ substances comprising a mixture of metals, or a metal to which small additions of other metals and non-metals have been added to give it special or desired properties. The result is a compound that is likely to be superior in performance to the pure metal and may be more economical in use. Steel is an example of an alloy.