Modern architecture cannot be imagined without modern materials and techniques that withstand huge static pressures and are reliable in all weather conditions. Since the invention of steel-reinforced concrete, buildings have become higher and much sturdier than before, not to mention less prone to damage from natural disasters such as earthquakes and fires.
So whoever is in the business of making a lasting structure, be it a weekend getaway hut or an office building, they are almost sure to come across steel reinforcement at one point.
The reinforcing mesh is a net made out of steel bars to a certain standard, used for giving additional support and flexibility, if needed, to a concrete slab, column, or other structure. It allows for much more stable floors and walls and gives the ability to carry more weight per square foot than regular concrete floors. All in all – a very handy and versatile material that should be, and is, regularly used on construction sites.
Steel Grades
Put simply – steel is iron with some carbon and other trace elements added. This is, of course, very vague. Still, the subject of steel as a material is very complex, and several international standards exist that try to define precisely what are the properties and purposes of a certain grade of steel.
In Australia, most engineers and inspectors refer to the Australian Standards and Codes of Practice as guidelines for the various steel grades and purposes that can be found and used in the country. When buying foreign steel, the characteristics should be compared to the domestic standard to ensure it is up to code. Some design standards that cover the aforementioned category of reinforcing meshes are, for example, AS 4100 and AS/NZS 4600.
Where to Get It?
Depending on the scale and specific need of the project you are working on, you will be looking for steel supplies in various places. Small DIY projects such as fixing cracked driveways or making artistic sculptures require small amounts of steel reinforcement and can easily be bought in most local hardware stores. Steel is usually bought by weight, but depending on the reinforcement in question (such as a certain welded pattern or structure), that will also pick up the price a bit.
Larger orders require contacting wholesale suppliers who usually have competitive prices and are in touch with foundries that are producing the steel they use and sell. Bigger suppliers such as Reozone routinely have civil engineers as part of their workforce and can be asked to meet specific needs for non-standard projects or advise if you are not sure what standard fits your requirements best. Considering how important steel is for safe construction, it is imperative to get it from a reliable company.
Types and Purposes
Several different types of reinforcing mesh can be found on the market today and, while their prices can vary drastically, they are all meant to serve a specific construction purpose:
Sheet Metal Reinforcing Mesh
Used for giving support to floor slabs, stairs, and for roofing.
Stainless Steel Reinforcing Mesh
Stainless steel is far more expensive and harder to work with than regular construction steel grades, but it comes with the huge benefit of corrosion resistance. Areas prone to corrosion, such as those exposed to seawater, for example, or are just very difficult to fix later on, benefit from being reinforced with such a material.
Expendable Metal
This type is made as a much finer mesh out of wire that has a certain flexibility. It is either used for lighter concrete installations or for adding strength in plaster when building brick walls prone to settling in the future.
Making Reinforced Concrete
Doing this correctly takes some preparation, but it is a rather straightforward job. Formwork comes first as the concrete volume needs to be defined and supported first before any pouring or assembly begins.
Next off, the first reinforcing mesh must be placed evenly across the surface, taking care that it is not on the bottom of the form and that any later mesh is placed evenly apart.
Later – concrete is mixed and poured over so that the steel is completely covered and so that no pockets of air remain. The concrete is then left to dry and harden the same as normal concrete.
Any civil engineer who knows his job will tell you how reinforced concrete is the backbone of modern construction. The sheer amount of concrete that is poured every year throughout the world is a testimony to this. Until a more reliable material is found, steel will remain the undisputed favorite reinforcer everywhere on the globe.