Reinforced concrete frame of buildings: prefabricated, metal and wooden (main elements)

The frame serves as the overall structure’s support when it comes to building construction. Because of their strength and longevity, reinforced concrete frames are a popular choice among the available options. There are various ways to construct these frames, and each has benefits of its own.

Concrete frames that are prefabricated are made in a factory and then delivered to the construction site. Accurate quality control and expedited on-site assembly are made possible by this method. Contrarily, metal frames are flexible and have a high load-bearing capacity, which makes them appropriate for bigger, more intricate structures.

Even though they are less prevalent in contemporary high-rise structures, wooden frames are still essential in some construction methods. They offer a lighter and frequently more affordable option, particularly for smaller or home-based projects. Knowing these choices enables you to balance budget, time, and structural requirements while choosing the ideal frame for your building requirements.

Modern buildings must be supported by reinforced concrete frames, which are primarily of three types: prefabricated, metal, and wooden. Prefabricated frames are constructed quickly and consistently on-site using concrete components. Steel is used in metal frames for flexibility and strength, making them perfect for high-rise buildings. Though less popular, wooden frames offer a traditional aesthetic in a sustainable option. Selecting the appropriate frame for particular construction requirements is made easier by being aware of these various kinds.

Advantages and disadvantages

Because of their exceptional strength, reinforced concrete frames are essential to the construction of high-rise buildings. Selection of less desirable materials is acceptable in private construction. Accordingly, it is not economically justified to use steel frame reinforced concrete in private construction.

• high load-bearing capacity;
• fire resistance;
• long service life;
• low operating costs;
• reliability of the structure;
• the cost of producing such products is much lower than for structures made of stone or metal;
• the length of the spans allows you to create large rooms without additional supports (partitions, columns).

• high density;
• the need for curing until strength is acquired;
• high sound and thermal conductivity;
• labor intensity of repair work, reinforcement of the structure;
• the material may crack due to shrinkage and force impacts.

Types where it is used in construction

Technology of construction of reinforced concrete frame structures

The type of metal structure and the number of floors determine the building construction method. Precast, monolithic, and combined structures are available.

1. No need to heat the workplace in winter, which significantly saves energy costs.
2. The ability to leave reinforced concrete materials at the construction site, which ensures the continuity of the assembly process of the structure.
3. Reduced need for non-professional labor.
4. Availability of additional space, which is absent in monolithic construction.
5. Frame elements are manufactured at the factory, which allows you to do without welding.
6. Speed ​​of building construction.
7. Achieving strength immediately after installation.

Among the drawbacks are the high material consumption for supports and the manufacturer’s default form limitations because the reinforcement is not bendable.

Prefabricated structures

The frame elements have holes drilled in them or special loops put on them to make transporting them easier. At the construction site, the parts are fused together.

Such frames are designed with the assumption that there is a reinforced concrete foundation. On it, columns are positioned every 6 to 12 meters. For foundation beams, concrete grades 200–400 are utilized. The load-bearing walls will be supported by these components. The floor level is 3 cm higher than the upper side of the beams due to their placement. Concrete fills in the empty space. For this, grade 100 is appropriate.

Waterproofing is done to protect the floor from freezing and to ensure that the soil’s influence on the beams doesn’t damage it. Columns 1.020, suited for loads up to 500 tons, or ten stories, are used to erect large structures. One row of cellular concrete blocks is used to construct the exterior walls. The facade’s flexibility is maintained since there is no rigidity. On floor slabs or beams, the blocks are placed.

Masonry can be applied in one or more layers when constructing a supporting structure out of tiny blocks. As you build this kind of structure, you have to be careful that the masonry doesn’t support the frame. The need for thermal insulation is taken into consideration when choosing the wall thickness. This measurement should be 50 centimeters in residential buildings.

Additionally appropriate for internal partitions (between rooms, apartments) are cellular concrete blocks. Every floor has its own set of walls. The need for sound insulation (more than 50 dB) is the primary consideration when designing the thickness of ceilings and partitions.

The parameter can be calculated using regulatory documents. The type of block, mortar, concrete, etc. used will determine this. An empty space filled with a miniplate will help eliminate background noise. The material should have a density of 80–100 kg/m³.

Interior wall thickness should be 12 cm, and sound absorption should be at least 43 dB.

The most common application for prefabricated frames is in the construction of two to five story industrial buildings. A steel base is recommended when constructing a taller structure that calls for heavier crane loads. Its constituent parts, such as the connecting elements, crossbars, and columns, can be lattice or solid. They are constructed with welding machines to join channels, angles, and other profiles.

When building low structures without wide spans or heavy loads, frames with stone supports are used. By using reinforced concrete cores, steel mesh reinforcement, or reinforcement, the bearing capacity is increased.

Precast-monolithic frames

By using such frames, the main benefits of monolithic structures can be preserved while lowering the labor intensity and duration of the work.

In this version, thin-walled, square-cross-section formwork is used to concrete the columns and beams. When concrete is poured into the columns and beams, the joints between the reinforcement and formwork become monolithic.

Pretensioned or regular concrete is used to make the components. In this instance, the walls’ thickness should be between 8 and 12 cm. More reinforcement will be needed if regular concrete is used.

1. Columns are mounted in a recess in a reinforced concrete slab on which panels with voids are placed, span elements are installed on top.
2. The reinforcement mesh, which is located between the panels, is welded to the reinforcement bars of the span elements.
3. The concrete mixture is poured.

Monolithic frame

It is possible to build a monolithic frame with both permanent and movable formwork. The construction of private, low-rise homes is more frequently accomplished with this type. The formwork functions as a supporting structure once it has been joined to other components and filled with concrete. Modern construction uses a variety of materials, foam among them.

1. Panel. Formwork of this type is created from individual parts that are connected with special fasteners. In this way, a container is formed for pouring concrete, which will become the foundation of the future building.
2. Tunnel. Formwork is purchased assembled, which is why this type of construction is not suitable for all installation work. Purchased products are not subject to change. They are filled with mortar immediately after installation.

When a substantial amount of concrete is needed, the company places an order for it. The mortar can be mixed separately in a different situation.

Compaction of the concrete is required once the laying process is finished, as this will prevent voids from forming in the structure. For the job, specialized instruments are appropriate, such as surface and deep vibrators.

Compaction will help the monolithic frame reach its maximum strength. Following the process’ conclusion, they move on to strengthening the structure. The technology’s features let you put different design concepts into practice.

For modern buildings, reinforced concrete frames are essential because they offer stability and strength. Every kind of frame, whether made of prefabricated materials, metal, or wood, has special advantages and uses.

Because prefabricated frames are made off-site and put together fast, they provide efficiency and consistency. Known for their strength and adaptability, metal frames are frequently found in industrial and high-rise buildings. Although they are less common in large-scale construction, wooden frames are an attractive and environmentally friendly choice for residential buildings.

Selecting the best frame type for your building project requires an understanding of its advantages. Every technique adds to the structure’s overall functionality, safety, and design, making sure it satisfies both utilitarian requirements and aesthetic standards.

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