Steel is a material that by over a hundred years has a predominant role in constructions; thanks to its high resistance in relation to its section, can withstand large loads, taking up little space, thus giving the idea of lightness and modernity at the same time, bringing a huge fortune to this metal along the years. Hence, many facilities that before were supported by wood, now have been replaced by a steel structure, even more durable over time and resistant to atmospheric effects. This metal finds nowadays a remarkable application not only in the civil case, but also especially in the industrial sector, where the ancient bolting, has been replaced by welding, more reliable and aesthetical. Steel has therefore occupied an increasing market share, and this has been due to improved production techniques, the use of PCs (that allowed the automation of processes), and the introduction of oxygen, which facilitated the machining. Moreover, thanks to its characteristics, it is good to be applied in contexts where is needed a considerable flexibility of construction and design.

DESIGN

Is not easy to define a “structure”, because the legislation is in many case old, and as you can imagine, with the development of materials, such definition would no longer be fully in point. That said, we can consider a structure like an organized set of different interconnected elements.
The design of steel structures, referred SMEA Engineering deals with, is divided into some basic steps in order to obtain a satisfactory result:

1. The first thing to do is to carefully choose the materials, their geometric design and their effect on the structure;
2. After you draw a preliminary design, ie a sketch that is usually based on the experience and remains as close as possible to practical concepts and to the use of the building;
3. Is then the moment of some structural considerations, also considering the influences of external components;
4. Test of robustness, in which it is checked that the structure is more resistant than stresses which act;
5. You ultimately controls that the curvature imposed by the loads to the structure are in line with the law; if it’s not like that you have to re-size the construction, otherwise the project is completed.

There are also some design criteria that a steel structure must respect in order to get a good result:

• A project must be simple, to avoid making even more uncertain and variable a subject that already is like that by nature;
• It’s important to respect a certain forms regularity that go to seek symmetry and lightness, without leading to excessive forcing of style; this point should be considered in general, that is to say for the whole dimension of the structure, from the base up to the beautification elements;
• The supporting structure must be imagined and designed taking into consideration the possibility of failure of some of its components, and it must therefore provide alternate discharges of forces to the main ones designed, without ever being just sufficient for the intended use, but abounding in safety;
• It’s important to choose materials whose wear is predictable over time and does not stipulate special and unexpected surprises; the predictability of the deterioration is essential in order to plan interventions analysis;
• Finally, the materials must guarantee characteristics in line with the legislation, both as geometry and as mechanics; if are used material that are not mentioned in the regulations, the supplier will have to guarantee the suitability of the service.

ADVANTAGES

The use of a steel structure has several advantages compared to other materials used to construct:

• The steel has a greater resistance in relation to the specific weight compared to concrete; this allows to create finer frames that bear less on the whole structure, thus allowing to implement smaller foundations and great light environments;
• It adapts well to calculations models, being very consistent under stress until the permanent deformation;
• It can be easily worked in the workshop and then quickly installed because the items arrive on site ready to be assembled;
• The material offers particular guarantees against corrosion and fire;
• Steel disposal is easy and inexpensive;
• It has a particularly flexible use, making it possible to change the destination on construction site.

All these undeniable advantages, made steel an ubiquitous element, able to adapt to many situations without compromising strength, safety and reliability, making it a benchmark in the construction of civil and industrial structures, designed for decades successfully by SMEA Engineering.