Reinforced concentrate, is a composite material in which the relatively low tensile strength and ductility of concrete are nullified by the inclusion of reinforcement of higher tensile strength and/or ductility. Reinforcement is usually, although not necessarily, reinforcing steel bars (rebar) and is usually passively incorporated into the concrete before the concrete sets. Reinforcement schemes are generally designed to withstand tensile stresses in certain areas of concrete that may cause unacceptable cracking and/or structural failure. Modern reinforced concrete can contain varied reinforcing materials made of steel, polymers, or alternative composite materials in conjunction with or not with steel reinforcement.
Reinforced concrete can also be permanently pressed (in case of compression), to improve the behavior of the final structure under working loads. In the United States, the most common ways to do this are known as pre-tightening and post-tensioning.
For a strong, flexible and durable structure, the reinforcement must have at least the following characteristics:
- Relatively high strength.
- High tolerance to tensile stress.
- Good bonding to concrete, regardless of pH, humidity, and similar factors.
- Thermal compatibility and not causing unacceptable stresses in response to temperature change.
- Durability in the concrete environment, regardless of erosion or constant stress for example.
Properties of this Reinforced concentrate:
- It shows a strong cohesion with the surfaces of the iron bars, and accordingly, the concrete transfers the extra stresses that it cannot resist by itself to its iron bars.
- The coefficient of longitudinal expansion of concrete and iron are close to each other, and therefore the internal stresses in reinforced concrete do not appear as a result of temperature changes.
- Cement protects iron from rust and at the same time does not react with it.
- Live for a long time with resistance to fire, insects, and worms.
- Maintaining it does not cost anything.
- Easy to form to any desired shape.
- It is economical in the long run.
What is the minimum Reinforced concentrate jacketing for rebar?
The thickness of the concrete cover at each end of the steel reinforcement shall not be less than 25 mm or the diameter of the reinforcement shall be doubled. The covering around the iron in the weathered concrete surface such as the base, sides, sills, and retaining wall in direct contact with the ground after removing the formwork shall not be less than 50 mm.
Concrete surfaces exposed to harmful chemicals (such as salt water, acid, alkali, smoke, and sulfur) must be implemented in such locations, as described in the details (considered special cases). For the structure used to store liquids such as tanks, swimming pools, etc., a concrete cover of 40 mm or larger diameter main reinforcing bar, whichever is greater, must be provided for all reinforcing bars.
In the area where there are waters of a corrosive nature, oil, and seawater, the cover should be increased by 10 mm.
Concrete surface exposed to harmful surroundings, in such a case the reinforcement can be protected by using impermeable dense concrete with an approved protective layer. In such circumstances, additional coverage may be reduced, as mentioned above in the previous paragraph.
The required concrete cover shall be provided using cover blocks (cement mortar cube or other approved method). EIC-approved precast concrete blocks shall support reinforcing reinforcement in studs, bases, and slabs on the ground. Oftentimes, unskilled workers use breaking bricks or bricks, lifting reinforcement during pouring, or moving it in place of the concrete cover block. This should not be allowed.
Source: wikipedia.org/wiki/Reinforced_concrete
Read More: buildineg.com/public/blog/what-is-a-concrete-jacketing-of-column/
