What is reinforced concrete: types, scope

A common and adaptable building material in construction is reinforced concrete. It creates a material that can withstand a range of stresses by fusing the tensile strength of steel with the compressive strength of concrete. Because of these factors combined, reinforced concrete is a crucial part of contemporary engineering and architecture.

Different types of reinforced concrete exist, each with a specific function in mind. Steel bars, also known as rebar, are embedded in the concrete to provide traditional reinforced concrete. Another type is pre-stressed concrete, which is concrete that has steel cables twisted before it is poured. Large buildings and bridges that need extra strength and flexibility frequently use this kind of construction.

There are many uses for reinforced concrete. It is employed in the construction of roads, bridges, buildings, and dams. The robustness and resilience of reinforced concrete render it perfect for use in infrastructure projects. Creative architectural designs, ranging from straightforward structures to intricate forms, are also made possible by its versatility.

It is easier to appreciate reinforced concrete’s influence on the built environment when one is aware of its types and applications. In order to give strength, safety, and longevity to buildings all over the world, reinforced concrete is essential to construction, whether it is used for a bridge’s span, a skyscraper’s frame, or a house’s foundation.

What is reinforced concrete?

Steel and concrete are used in the manufacturing of reinforced concrete, a composite building material. A cement, sand, and water solution is poured into a pre-assembled iron frame during the manufacturing process. When it solidifies, reinforced concrete is created, making up for its shortcomings with the strength of steel and the resistance to environmental elements of concrete. Specifically, resistance to tension and compression.

Concept and historical background

Joseph Monier, a French gardener who grew exotic plants in the Versailles greenhouse, created the first reinforced concrete. He sold palm seedlings and made very little money doing so. The majority of the earnings had to go to a cooper who made wooden pots for future palm trees.

A ceramic vessel would have been a less expensive option, but it is a very delicate item, and it would break easily if the gardener fell and missed a bag of cement on the ground. However, it was this incident that inspired him to use cement and sand to create pots. And this is where our hero faced a disaster: over time, the roots of plants with strong growth forces were able to easily destroy the material. He sewed it into a metal frame for strength, but the result was unsightly, so the gardener covered it with another layer of concrete on the outside.

Consequently, these pots proved to be both affordable and useful. Following that, Joseph Monier successfully patented his invention, as the qualities of that material saw a rise in demand in the building industry. Everywhere reinforced concrete started to be used to construct dependable, long-lasting buildings and structures that could withstand a variety of environmental conditions.

Types by manufacturing technology

Products made of reinforced concrete are:

The structure’s supporting base is frequently poured on location, and its upper portion is put together using industrially prefabricated components.

• Ordinary.
• Prestressed.

Prestressed concrete is made using a relatively straightforward technology that is not all that dissimilar from that used to make regular concrete. The reinforcing mesh is pre-tensioned, which is the only difference. When the tensioners are removed after the concrete hardens and the tension energy acts on compression, it is transferred to the entire product, giving it increased resistance and compensating for weight tensile loads.

• reinforced concrete pipes (T, TBR, TSP);
• well rings (K);
• road slabs (PD);
• piles (S);
• rectangular cross-section piles (SG);
• slabs for strip foundations (FL);
• basement wall blocks (FBS);
• purlins (PRG);
• bar lintels (PB);
• hollow core floor slabs (PC).

Advantages and disadvantages

It is a heavy, robust, and dense material that is resistant to a wide range of temperatures. It also lets air flow through and absorbs moisture poorly.

1. Strength and wear resistance.
2. Self-compactibility. Over time, it becomes harder and stronger.
3. Resistance to loads.
4. Durability.
5. Fire resistance. Structures made from this material do not ignite, do not contribute to combustion.
6. Chemical neutrality.
7. Technological. It is possible to produce products of any shape, give them any color using additives.
8. Low cost.

1. Compared to pure metal, low strength.
2. It takes a fairly long time to produce products and their components.
3. Decent weight. Even the use of lightweight concrete does not allow to significantly reduce the weight.
4. The probability of cracks after shrinkage, which should be noted do not affect the properties of the product and do not ensure its destruction.
5. Low level of heat and sound insulation.
6. Poor air permeability. Buildings made from it require a ventilation system if people are planning to stay in them for a long time.

Because of its increased strength and durability, reinforced concrete—a composite material made of concrete and steel reinforcement—is crucial to modern construction. Precast, prestressed, and fiber-reinforced concrete are just a few of the types of reinforced concrete that are available; each is appropriate for a particular use. It is a mainstay of modern architecture and engineering due to its adaptability, which enables it to be utilized in everything from residential buildings and bridges to high-rise structures and industrial complexes.

Properties and composition

In reinforced concrete, cement, water, sand, and iron are all present. Compared to metal, the product uses more concrete. Simultaneously, the steel frame’s design and the specific gravity of iron may differ. Everything is dependent on the intended end product, which could be a foundation, column, pile, or slab.

• strength;
• reliability;
• durability.

Types of reinforcement

1) based on the objective:

• working;
• withstanding maximum tensile loads;
• distributing loads across the entire surface of the product.

2) based on the technology used in production:

• rod. This category includes rods, bars of any diameter, manufactured using hot rolling technology;
• reinforcing wire. It is produced from both low-carbon and high-carbon steel.

The reinforcing elements can have a smooth or corrugated surface.

Types of concrete

Structures made of reinforced concrete can be made with either light or heavy concrete. Here, the latter are frequently employed.

Concretes with a minimum class B15 compressive strength are used in the production of excess reinforced concrete. The product has rod reinforcement of classes A240, A300, A400, A500, and B500, with a minimum 40 mm diameter. The pouring structure is made up of flat grids and spatial frames. Rigid reinforcement is frequently employed in conjunction with profiled steel blanks, such as angles, channels, and I-beams.

Concrete grades B20 through B60 (heavy) and reinforcing steel A540, A600, A800, A1000, BP1200, BP1300, BP1400, BP1500, K1400, and K1500 are used to produce overstressed reinforced concrete.

Steel fiber concretes are composed of unique concrete mixtures reinforced with tiny metal plates.

Characteristics

Reinforced concrete: what is it? The properties of two distinct materials have been successfully combined to create a single monolithic structure. To begin, a pouring mold needs to be made. After that, a steel frame is created. After mixing, a solution is poured into the mold. For the product to obtain the necessary qualities, it must stand for a specific amount of time. Significant adhesive forces form between the concrete and reinforcement during the hardening process, causing both materials to deform together under specific loads.

Among this material’s beneficial and in-demand qualities in contemporary construction are:

• high density;
• ability to withstand very large weight and impact loads;
• resistance to moisture, high and low temperatures, and their sharp fluctuations.

The metal enclosed in the concrete is shielded from corrosion by its density and resistance to moisture. In the event of a fire at the structure’s location, the hardened solution shields the iron from coming into direct contact with flames.

About the same coefficient of linear expansion applies to both materials. This explains why the original integrity is maintained even when exposed to high temperatures and no internal ruptures or destruction are seen.

The following guarantees a robust bond between the components of reinforced concrete:

• special protrusions that provide 75% of the total adhesion value;
• friction forces;
• adhesion (bonding) of concrete and metal elements

A versatile and indispensable material in contemporary construction is reinforced concrete. Its special blend of steel reinforcement and concrete gives it the strength and longevity required for a wide range of constructions, from large-scale infrastructure projects to residential buildings.

Certain varieties of reinforced concrete, like prestressed and precast concrete, have unique benefits for various uses. Because of these options, engineers and builders can select the material that best suits the requirements of their project while maintaining efficiency and safety.

Reinforced concrete has applications far beyond basic construction. It is utilized in bridges, roads, dams, and other important constructions that call for durable materials. It is an essential tool in the construction industry due to its strength and adaptability.

In general, everyone working in the construction industry needs to understand the various kinds and applications of reinforced concrete. It is essential in forming our built environment and laying the groundwork for development that is both secure and long-term.

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