Any construction project involving concrete will likely make use of reinforcing bars, more commonly known as rebar. Rebar refers to bars or a mesh of bars whose basic function is to reinforce concrete and masonry structures. This video explains everything we are about to detail in our article:
Introduction to Rebars
Reinforcing bars have been in use since the 15th century in various rudimentary forms, but it wasn’t up until mid 19th century that the method of embedding rebar inside concrete came about.
This was the birth of the modern method of reinforcing concrete. Although the most common rebar material is steel, you can come across other materials being used in specialty construction projects such as carbon fiber, basalt fiber, stainless steel, or even bamboo where steel might be a rare commodity.
Many people ask the question why concrete, which we all know to be incredibly strong, would need reinforcing. The answer lies in the way concrete responds to different kinds of stress.
Concrete holds up very well when compression force is applied to it – in the pillars supporting a building, for example. The same cannot be said when tension forces are applied to it, as in the case of an earthquake where the concrete is being ‘stretched’ apart. Reinforcing the concrete is meant to help the concrete hold together in such scenarios.
The uses of rebar throughout the concrete construction industry all over the world are as vast and varied as the architects and engineers can imagine them, and you’ll find rebar in every type of structure imaginable. If it’s made of concrete, it’s usually safe to assume that there’s rebar somewhere in there.
Specific cases aside, there is a general classification of rebar usage under which every individual application will fall, as follows:
This refers to the use of rebar to ensure that the entire structure is provided with enough support. This is the type of rebar application you will find in the main support columns of a multi-level building, whereby the columns support a massive weight concentrated upon them.
This is rebar application that works to support primary reinforcements in general. Secondary rebar application serves to diffuse the load of a structure away from a single focal point – the column in our example here. You will find secondary reinforcement rebar in the stretches of concrete running along the edges of floors, along the tops of walls, and connecting the tops of load-bearing columns.
Think of them as tying everything together so that in case anything should happen and one of the main columns fails, the strength of the remaining columns will help keep that section of the construction from collapsing completely.
Other Reasons For Using Rebars
Aside from the two main classes mentioned above, rebar is also used for a few other reasons. It can be applied as a framework for holding other steel bars in the correct position to support their loads (e.g. column-free stairways and shelving). It may also be employed as an external method of stabilizing and reinforcing structures, although this is a rather old-fashioned construction method first used in ancient Rome.
All in all, rebar has proven its usefulness in the construction industry, having pushed the boundaries of what we could do with concrete. It has made our man-made world safer, more impressive, and many time more durable.