Most steel constructions are done with a type of steel called mild steel. Soft steel is a very strong material. Choose a steel bar with a cross section of 25 mm in diameter. If you attach this bar well to your roof, it can carry 20,000 kilograms (20 tonnes), the equivalent of 18 Honda cars or 2.5 African elephants or 1.5 London double-decker buses. These cases indicate the high strength of mild steel, which is used in the construction of steel structures of buildings as beams and causes high strength of steel structures. This mild steel has a long life if it is protected from rust.
This extraordinary strength brings many benefits to buildings. Another important feature of steel frames is their flexibility. These materials can bend without cracking, another great advantage of which is that a steel structure is flexible and can deform easily when pressed by lateral loads such as wind or an earthquake.
The third characteristic of steel is its plasticity or ductility. This means that when it is subjected to a huge force, it does not suddenly crack like glass, but slowly deforms and bends. This feature allows steel buildings to deform slowly, thus giving residents enough time to escape. Damage to steel frames is not sudden, and steel structures rarely collapse. In most cases, due to these properties, steel performs much better in the face of earthquakes than other materials.
However, one of the important characteristics of steel is that it quickly loses its fire resistance. At about 500 degrees Celsius (930 degrees Fahrenheit), mild steel can lose almost half of its strength. This is what happened in the collapse of the World Trade Center in 2001. Therefore, steel in buildings must be protected against fire or high temperatures. This is usually done by covering them with plates or spraying materials called fire protection, which in case of fire prevent heat from reaching the steel frame of the building and make the structure stable.
Steel structures are often used in the following cases:
In environments with low humidity, one of the best options for the construction of buildings with steel structures are both short-lived, high-strength and long-lasting, which is a good option for residential buildings. .