Specialists on house construction say that among those materials frecuently used for estructural purposes, Steel is the one that has the best resistence, rigidity and ductility properties. According to what the Book called “Estructural Design for Architecture” says, “...(steel) its structural efficiency level is high since steel can be produced in sections with the most appropriate form to resist inflection, compression or any other kind of requirement.”
We can mention the following advantages in this sense
Resistancy: It is the quality by which a material resists the action of natural forces. There are 3 basic efforts: compression, tension and shear strength. The steel high resistance, by unit of weight, implies the structural weight will be minor, and that is to be considered as an important element whenever we talk about erecting houses on land which is difficult to lay foundations on.
Fire resistance: Structures made of this material are fire resistant, that is to say, they will not burn or inflammate. This fact constitutes an important security element for building up.
Versatility: Light steel allows the construction of any kind of house, including those of various storeys. Steel can be sectioned at the construction site with ordinary construction tools.
Ductility: Ductility is the property by which a material is capable of distorting before breaking. This characteristic is very important to the structural design, because a material capable of distorting is usually very resistant to impact forces. There is also another advantage of steel that is its capacity of giving signals before a fracture may happen due to its ductility.
In this sense steel has a high capacity of absorbing And disipating energy. This fact brings better conditions of resistance and durability in repeated charging cycles.
Durability: Steel is resistent to the action of termites, mold and rodents, provinding the structure with a long life existence.
Performance: It is said that one of the most important virtues relating to metallic constructions, apart from its low weight, is the possibility of quick erection. For example, there exists a historical record on erecting buildings of more than 3 storeys: the Empire State Building ( New York, 1931), and John Hancock ( Chicago 1970). The Crystal Palace (London 1851), where the Universal Exposition was held, was fully erected in 4 months (77.000 m2).
Recyclable: Steel is considered as the most recyclable material in the construction field, as it can be separated magnetically from any other materials in a fast and easy way. Recycled steel represents almost the two/ thirds of the all steel produced within the United States. This fact implies saving energy and raw materials, apart from being the most environmentally friendly.
Rigidity: The capacity by which any material may resists deformations is called Rigidity. If 2 blocks of the same size, one made of wood and the other one made of steel are subjected to the same compression force, the wooden block would shorten more than the one made of steel. Deformation ( shortening) of wood is probably 30 times bigger than steel. That is why it is said that steel is more rigid.
