Composite reinforcement: just marketing or really high-quality material
My friend is building a house. He was about to pour the foundation, and he was offered to use composite reinforcement. He calls me, asks what it is, and whether it is worth agreeing. We conferred for a long time and decided to look for information, to learn from friends.
Composite rebar - what it is?
It is made from glass or mineral fiber. Carbon and aramid are also used. They produce a whole line of materials of different price and composition.
In the middle is a fiber rod fastened with a composite material, the same fibers are wound on top for adhesion to concrete.
Color: yellow fittings - made of glass, black - made of basalt, carbon composite. In general, the shades are different, depending on the composition.
Why is she so highly recommended?
- It has been used in construction for a long time. For foundations, monoliths and tape too.
- Such fittings do not rust and do not lose strength during temperature changes.
- It can be quite thin and light, thereby reducing the overall weight of the structure, which is beneficial even in terms of shipping costs.
- The fibers have low thermal conductivity - that is, the house will become a little, but warmer due to this.
But you will have to do additional calculations, since under high pressure the plate can bend. I'm not sure if this disadvantage has anything to do with the monolithic slab that lies on the ground. This is a fairly solid base that will keep its shape. And a private house is unlikely to create dangerous pressure.
The structure itself will have to be prepared in the factory according to the project, since it is impossible to make bends right on the spot, special conditions are required. For a monolith, bends are usually not needed, so we note this drawback.
If a fire occurs, the heated fittings will lose their rigidity - you will have to take some measures in this case.
And most importantly, the composite will begin to lose its properties in 20-30 years. Of course, now manufacturers are talking about some additives that slow down the wear process, but it is not known how many years the reinforcement will be really strong. Although in the Soviet Union they built on composites, and nothing has collapsed yet.
What is saving
A running meter of reinforcement costs more than metal, but it requires a minimum of transport and does not create costs during unloading.
Savings are also achieved by purchasing thinner rods. Such a replacement will require engineering calculations, taking into account the class of metal fittings, but this is a fact. To replace a metal bar, a thinner composite bar is needed. This also affects the cost - the entire composite kit can be cheaper than steel bars.
Nothing needs to be cooked, there is enough strapping - the lack of welding saves some money in your pocket.
If you look at the regulations that must be observed, then composites are allowed.
They are used:
- for fences on concrete bases
- garages
- baths
- reinforced masonry made of bricks and foam blocks
- floors and foundations.
There are limitations, but they mainly concern structures with complex architecture.