Column formwork is designed to form an area of a square or rectangular area, which will allow the column to be properly mounted. There are different types of formwork that are designed for certain types of construction work. In this article, we will consider the features and parameters of the installation of formwork for columns with detailed step-by-step instructions.
Column types
The main purpose of formwork creation is to form a certain shape for columns of the required height and parameters. There are two types of work, the first with which foresees the installation for universal columns, and the second is the formation of the formwork of columns with a fixed section. When carrying out installation, you need to remember about the features of installing additional panels.
Previously, columns were used as a decorative element in buildings. However, in the modern world, this type of product is intended as supporting elements for different types of buildings. There are several types of columns, which differ in geometric shape:
- round or cylindrical;
- square;
- multifaceted;
- rectangular.
It is worth noting that the universal column formwork is carried out for different types of columns and provides for the installation of standard shields with special holes for the kingpin, the pitch for which is 5 cm.For a fixed installation scheme, it is necessary to fasten the column using four corner elements and some formwork locks.
Formwork purpose and product requirements
The formwork of walls and columns is carried out to pour a concrete base under the supporting elements. This is necessary so that the mixture does not spread and after hardening has a square or other shape. It is almost impossible to carry out the installation of the column without this stage of work. Experts identify some of the requirements for the formwork:
- compliance with the dimensions of the structure;
- stability and strength of the installed product;
- the formation of a form through which the solution will not flow;
- smooth inner side;
- dismantling is not time consuming.
Column formwork: disposable, reusable, non-removable
The simplest and most convenient option for carrying out work is the construction of a disposable formwork. This construction is made of cardboard, which is wound in a spiral. The formwork product is water-repellent, which prevents the mortar from penetrating into the structure of the cardboard. Thicker PVC foil can be placed inside the cardboard column formwork.
The approximate diameter of such a formwork can be from 20 to 115 cm, and the maximum length of the product can be 12 meters. Depending on the parameters of the column, the height of the formwork can vary, as well as the thickness of the walls. For example, in the lower part of the structure, the wall thickness can be greater, which is determined by the maximum load of the concrete solution. The technology for carrying out the work is not complicated; for large volumes of the installation, lifting mechanisms can be used. Only two people may be sufficient to carry out the installation.
Another variant of the column formwork device is the construction of a reusable structure. As a rule, the formwork can be used several times for the installation of several columns. There are such features of work performance:
- the need for the construction of formwork at the construction site;
- pouring concrete mortar into the structure;
- curing for several days until the concrete is completely dry;
- removing the formwork structure and installing it in a different place.
When performing such work, it is necessary to remember to observe the rules for installing the column. When choosing a reusable formwork for columns and floors, it is necessary to calculate the height of the product, which should not be higher than the indicated shapes. When choosing this form of formwork, the pouring will no longer be monolithic. Therefore, you should carefully read the requirements and characteristics of the implementation of this type of formwork in compliance with the column height.
Reusable formwork is more expensive than disposable, which is determined by the following parameters:
- Required storage costs of the structure.
- Transportation of formwork for the installation of other types of columns and maintenance of it.
- Additional expenses for the use of lifting equipment services.
There are different types of reusable formwork:
- shield structure;
- beam-transom;
- steel formwork;
- plastic construction;
Formwork using panels is intended for square columns. Shields made of metal must be fastened together using different fixing items. It is important to place laminated plywood in the middle of the boards. Further, concrete mortar is poured after hardening, of which the formwork can be removed and moved to another work site.
A similar type of work has a girder-girder formwork for columns, for which you need to use the following products:
- shields;
- crossbars made of steel;
- beams.
This type of structure will make it possible to form reliable formwork of different heights. As a rule, such a scheme is used for the construction of round walls, columns, bridges, as well as for the formation of large vertical surfaces. The formwork technology resembles the assembly scheme of a children's designer, and all the details are fixed with spacers.
The steel column formwork is designed for square and round products. The main characteristic of the design is that after using it, it is necessary to clean and lubricate the sections. This type of formwork has a lot of weight, like a panel formwork, so it is necessary to use the services of lifting machines to move it.
A more affordable and lighter option is plastic column formwork. The main disadvantage of the product is the unreliability of the design, and to carry out the work, you will need to seek the help of specialists. It is advised to work with this type of formwork carefully and with special tools so as not to damage the walls. All elements of the plastic structure are interconnected using different parts.
There is another type of formwork, which is not removable. The use of this type of construction is rarely carried out, however, such a construction scheme is quite popular among builders. All blocks and blanks for formwork assembly are made on special machines. Thus, products with thin walls are created, which are sufficiently strong and reliable.
Formwork elements are made of high-strength concrete. Mortar preparation technology foresees the use of cement, sand and water. The peculiarity of concrete preparation is the compaction of pores with the use of rolled products. Thus, all the liquid is displaced from the solution, which increases the properties of frost resistance and concrete strength. Formwork products manufactured in this way have increased resistance to temperature and humidity changes.
Column formwork installation: installation and dismantling features
Before considering the installation technology for a particular type of formwork, it is necessary to study the standard characteristics of the work. Before installing the formwork on a concrete surface, it is necessary to mark the column parameters. As a rule, the column should be installed around a pre-prepared reinforcement frame. It is important to carry out all work using project documentation. Formwork panels must be assembled in an L-shaped form, which are fixed with nuts and a kingpin or through a corner, then it is determined by the type of column. The second and other tiers of the assembly of the structure must be assembled using a mobile tower-tour or scaffolding.
If the height of the formwork of round columns is higher than 4.2, then it is important to mount a special crossbar on the column, which will level the structure. The installed column must be checked for vertical position, which is carried out using braces or pushers. The brace is made up of the lower and upper area of the product, as well as a special connector. The latter must be mounted in a concrete surface, then, the upper part is attached to the highest point of fixation of the column, and the lower to the lower one. Using special tools and nuts, the column should be leveled and fixed in an upright position.
The peculiarity of dismantling the formwork can be done when the concrete is completely dry. First of all, it is necessary to remove the formwork braces, after which the locks are dismantled from the upper part and the shields are removed.
It's important to know! If the height of the mounted column is more than three meters, then the concrete must be supplied through a special window. In the next tier, it is necessary to remove one of the shields, which forms a window of the required size. Further, the shield is installed in its original place, after which the concrete solution enters through the upper part of the column formwork.
DIY step-by-step instructions for installing panel formwork for columns
The installation process must begin by marking up the workspace. It is important that it coincides with the parameters of the previously erected frame and reinforcement:
2. After that, the formwork is assembled from the panels on one side, and it is important to fix all the details of the structure using locks.
4. Having determined the thickness of the concrete wall pouring, you need to install the next formwork wall using the same technology.
5. At the top of the formwork, it is important to mount the running console.
6. After aligning all the walls of the structure, you can proceed to further work on the installation of the column and pouring the base.
It's important to know! In order to correctly install the panels on one side, it is necessary to use the crossbars, which will allow the formwork to be leveled.
The dismantling method consists in carrying out the work in the reverse order: first, the running consoles and tolper braces are removed. After that, the locks are dismantled from the upper area of the structure, and the formwork panels are removed.
Installation instructions for girder-girder formwork
Girder-girder formwork is a structure that consists of beams and girders. All parts are held together with clamps. The main material used in the work is wood, so all work is not time consuming. This material has a low thermal conductivity, in contrast to aluminum column formwork.
Such a formwork assembly scheme has many advantages, which is indicated by the reliability, strength and simplicity of the structure used. Carrying out work does not require significant costs, while the formwork is considered universal. Using this type of construction, columns of different sizes can be concreted. Also, using the girder-girder formwork scheme, concrete walls of different parameters can be erected. It is recommended to use only a screwdriver and a hammer to strengthen and shape the formwork.
Formwork advantages:
- it is used to install columns and walls of different heights and sizes;
- intended for the formwork of buildings of various shapes, for example, radius, round and inclined without unnecessary waste;
- allows you to get good quality concrete on the surface of the formwork;
- using this type of assembly of the structure, it will be possible to reduce the number of gaps and ties;
- the formwork is capable of withstanding a large concrete load, up to about 10 t / sq. m.
Detailed instructions for assembling the girder-girder formwork have the following sequence:
1. Preparing the working platform for the installation of the formwork.
3. Formwork beams of the required length are laid perpendicular to the girders.
4. These beams must be connected to the ledger using special clamps.
5. The approximate distance between the beams should be from 20 to 40 cm, which is determined by the design documentation.
It's important to know! When laying the beams, care must be taken to ensure that they do not line up with the tie-bolt attachment points. On the installed beams, you need to put laminated plywood sheets, while the joints should be in the middle of the beam. Plywood is fixed to the beams using self-tapping screws, which are screwed in every 35-40 cm. The length of the fastener should be 50 or 60 mm. The area where the self-tapping screws are installed can be putty, which will extend the shelf life of the plywood for further use.
There are different options for installing the formwork, however, not all work can be done by hand. The installation technology for each type of structure is determined by the height and section of the columns. To better study the formwork scheme, we recommend watching the video presented at the end of the article.
When the columns are poured with concrete, reinforcement work is performed at the beginning.
We install reinforcing rods with a diameter of 12mm in the form of a square (at the corners). These rods are installed vertically, they are also called column rods. For the convenience of mounting the reinforcement cage, platforms with fences are installed every 2m of height.
The installation of the frame is carried out in several ways.
With relatively small masses and dimensions of the future column, the frame can be turned over to the formwork body. If the frame turns out to be heavy (this is possible when using reinforcement with a diameter of 16 mm or more), then it is more efficient to assemble only the base separately, and fasten it already at the pouring point. When carrying out bandaging or welding, it is forbidden to stand on the rods to be welded. When welding, it is most convenient to use a portable welding machine. You can choose a welding inverter. Reinforcement bars can be welded together with wire, at a distance of 40-50 cm. For such purposes, you can use a special gun for tying reinforcement.
We install the formwork.
First, we assemble the formwork body. Particular attention should be paid to its fastening. The formwork is fixed during installation with of all sides of the future column (with a typical column - from four).
We mount wooden spacers on each side of the future column. If the column is high, then a slightly different method is used. The box body is mounted on three sides, and the latter is built up directly during concreting. During installation, the box is leveled and fastened with screws. On the sides, corners are mounted to maintain a right angle of 90 degrees.
Concreting process.
One of the most important parameters when pouring concrete into columns is the fluidity of the concrete mix. Mobility refers to the ability of concrete to distribute itself under the pressure of its mass. A concrete cone is used to measure the mobility. It is filled with concrete in layers. Then it is raised and the mixture settles under its own weight. How much the cone sags, such mobility can be assigned to mobility. Distinguish between mobile and rigid concrete mixtures. Mobility is marked with the letter “P” and a number from 1 to 5.
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Draft |
Designation |
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10cm to 15cm | |
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16cm to 21cm | |
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More than 22cm |
When pouring the columns, concrete P2 or P3 is used. And with a large number of reinforcement - P4 or P5 (cast concrete). It is excellent for casting into formwork without using a flexible shaft vibrator. Mobility increases as the fill proceeds.
Filling is carried out using a concrete pump or or as it is also called a bell. For this, the tray is removed from the bucket, and a funnel is installed in its place. On it with a clamp we install a canvas sleeve for pouring concrete. And put its free end into the formwork.
Filling is done in layers. The layers run horizontally and STRICTLY in one direction. As it fills, the mixture must be carefully compacted by removing excess air from the mixture. For this, the mixture is evenly pierced throughout the entire volume with a metal rod. After that, you need to walk with a vibrator. Be sure to make sure it is grounded.
If it is not possible with a flexible shaft, then you can periodically tap on the formwork with a hammer or rubber mallet. In the process, be sure to make sure that the formwork does not "go away" anywhere, and the frame from the reinforcement always remains strictly in the center.
The composition of the concrete mixture: 1 part of M400 cement, 2 parts of sand, 4 parts of gravel or crushed stone (size from 20mm), and water. The amount of water is taken from the calculation of obtaining a homogeneous mass. When the column is poured, reinforcement is attached to it using anchors.
We remove the formwork.
When the concrete gains full strength, the formwork is removed. Typically, the full strength of concrete mixtures is achieved in a period of 20 to 25 calendar days, subject to the optimal setting conditions.
In modern monolithic construction, columns are used quite often. In many projects of multi-storey buildings, they are not only decorative architectural elements, but also the main supporting structures of the entire building. This allows you to build premises on the next floor without repeating the plan of the previous one. To ensure the strength and durability of such monolithic structures, the column formwork must be performed reliably and efficiently.
Varieties of columns and formwork for their arrangement
According to the geometric shape of the section, all columns are subdivided into:
- round (cylindrical);
- square or rectangular;
- multifaceted;
- curly.
The most widespread are the columns of the first two types. The last two categories are used mainly for the restoration of buildings or decorative purposes.
By the number of cycles of use, the formwork for arranging the columns is divided into:
- disposable;
- reusable.
Depending on the material of manufacture, the formwork is:
- wooden;
- plastic;
- metal;
- cardboard;
- combined.
Cylindrical Column Formwork
Round column formwork can be either disposable or reusable.
As a disposable formwork for round columns, cardboard pipes are now quite often used. In their manufacture, paper tape, a special adhesive composition and a polymer material (to ensure water resistance) are used. This column formwork is available with an inner diameter of 150 to 1200 mm. Its installation is quite simple: the pipe is simply put on the reinforcing cage, then the support rings are installed, to which the spacer braces are attached (to give stability and vertical alignment). To quickly dismantle such products during their manufacture, a special metal wire is pressed in along the entire length of the pipe, pulling on which the cardboard is cut along its entire length, and then it is easily separated from the hardened concrete.
On a note! It is advisable to dismantle the cardboard pipe just before the end of construction. This will protect the support from technological damage.
Disposable formwork for columns made of cardboard has a number of undoubted advantages:
- low cost;
- ease of installation and dismantling;
- when using it, the surface of the concrete support is obtained of high quality;
- light weight;
- high strength.
Pipes (metal, asbestos-cement or plastic) are used as non-removable elements of circular cross-section. After the concrete solution hardens, this remains an integral part of the column structure.
Attention! When using metal pipes, their surface must be treated with an anti-corrosion compound.
The reusable round formwork consists of metal or plastic half-pipes, which are mounted around the reinforcement cage of the column using special quick-release locks. Plastic formwork for columns has less adhesion to concrete than metal (this provides ease of dismantling), but less strength.
Formwork for square and rectangular columns
This type of column is most widely used in both industrial and individual construction.
The most common type of removable formwork for arranging such columns is a large-panel formwork system. Universal panels (their dimensions: width - 0.4 ÷ 1.2 m, height - 1.0 ÷ 3.3 m) allow you to quickly mount the formwork for square columns (the cross section of which is from 0.2 - 0.2 m to 1, 0⨯1.0 m).
Longitudinal technological holes for fasteners (pins) allow you to create rectangular formwork. One column requires: shields (4 pieces, assembled into a "mill"), pivots with special tightening nuts (for a column about 3 meters high, as a rule, 16 sets are sufficient) and slopes (at least 2 two-level support ones).
The popularity of such a system is due to:
- simplicity and high speed of assembly and disassembly;
- the possibility of forming the section of the column in accordance with the requirements of the project;
- durability (from 80 to 200 concreting cycles, depending on the manufacturer and the material of the panels).
Another type of formwork system that is widespread in modern construction during the construction of columns is girder-transom. The main elements of this structure are formwork slabs, steel girders, beams of various sizes and fasteners. This type of formwork system can be easily adapted to create columns with square, rectangular and even octagonal cross-sections. Such steel column formwork has the greatest strength and durability compared to other materials (laminated chipboard, plastic or boards and plywood panels).
Self-production of formwork during the construction of columns
In the manufacture of formwork for monolithic columns with your own hands, you can use several methods.
The easiest way (but rather laborious) for making a formwork frame for columns of square or rectangular cross-section:
- From boards (25 mm thick and a length equal to the height of the column), using nails and self-tapping screws, we make a U-shaped structure with internal dimensions corresponding to the section of the future column.
- We make a shield from the same boards, which will later be the fourth side of the formwork frame.
- We install the U-shaped structure to the reinforcing cage and attach a board made of boards to it.
- We align the formwork vertically using a level and fix it with stops made of boards or bars.
- To give the structure additional strength, we tighten it with additional bars and studs with nuts.
- Now you can start pouring the concrete mixture.
The video will help you understand the above-described technology for manufacturing the formwork of square columns:
Another method for self-manufacturing is in many ways similar to the previous one. Instead of boards for the manufacture of formwork (preferably moisture resistant, 12 mm thick) and wooden blocks. We use reinforcing bars and quick-release spring locks (clips) as tightening elements. For vertical alignment, you can use rented telescopic stands.
On a note! It is advisable to apply the above methods if it is necessary to make a small number of columns (3÷ 4 pieces). Otherwise, the cost of materials and hardware for the manufacture of formwork will be quite high. If you need to build 10÷ 12 columns (for example, for a large glazed terrace or veranda), then the column formwork on universal panels, rented (the cost of renting one set, which includes: 4 panels, 2 two-level telescopic slopes, a set of necessary fasteners, will be about 7,500 rubles per month). And since the stripping of the column can be done within 48 hours after pouring the concrete solution, then for the paid month you can easily make the required number of columns.
In custody
The final choice of one or another type of formwork for the manufacture of columns depends on their number, section size and height. Of course, only high-tech professional formwork systems are used for the construction of bridge supports or flyovers. And for the construction of several not very high columns with individual construction, you can completely get by with a form made from scrap materials. The main thing is that it strictly corresponds to the geometry of the future column and can withstand the pressure of the concrete solution without deformation.
Monolithic columns - part of the building, vertical load-bearing elements. The columns are supported balconies, terraces, ceilings... In addition to the main functions, the columns are a decorative element, decorate the entrance group of the building and the facade.
Columns receive and transfer the load from the upstream elements to the foundation of the structure. Reinforced concrete pillars connect the structure, serve as a support for the floors.
The architectural term "column" refers directly to to the middle part, support post... The protrusions in the upper part of the post for supporting slabs or crossbars are called capitals or consoles... Sometimes there is a sub-column, a glass for attaching to a columnar foundation.
Types and types
Concrete columns are subdivided by section type, production method.
By the type of section, they are subdivided square, round or rectangular shape.
According to the method of production, they are classified prefabricated elements delivered to the site by ready-made structures or erected at the construction site, monolithic columns.
Features of the device of monolithic columns
Then they go directly to construction:
- collect the formwork;
- mount the reinforcing cage;
- concrete mixture is poured;
- carry out concrete care procedures;
- withstand time for the strength of the mixture;
- unroll constructs.
Monolithic reinforced concrete columns count at the design stage... The section and shape of the column, the diameter of the reinforcement, the type of used will depend on the amount of the planned load, including the dead weight of the element.
Important! Deficiencies in installation and miscalculations lead to the destruction of the structure. With a lack of cross-section, buckling deformation occurs, the column bends under load.
Preparation of tools and materials
The need for materials and tools is determined at the stage of preparation for work. Of the tools you will need:
- metal square, level for checking the verticality and horizontalness of surfaces;
- steel bar, will help release air;
- screwdriver for fastening the formwork;
- vibrator thickens the mixture;
- prefabricated formwork from shields, props.
The concrete mix is delivered to the construction site ready-made or mixed immediately before laying using a concrete mixer. For preparation, take one part of cement, add two parts of sand, mix with two parts of crushed stone and two parts of gravel. By mixing the dry mixture with water, plastic concrete of a homogeneous consistency is achieved.
In addition to the concrete mix, the following materials are required:
- nails, screws for fastening the formwork;
- reinforcing bars of the design section and length;
- steel wire;
Formwork installation
The formwork is installed in the design position. Shields are vertically aligned and reinforced with struts, wooden struts... The braces are anchored with support blocks in two directions to prevent shearing.
When concreting a tall column, the formwork installation process is somewhat different from the usual one. Three sides of the form are mounted, and the fourth side is closed as the formwork is filled with concrete.
Reinforcement
By tying rods together, they receive rigid volumetric frame to strengthen concrete. The number of longitudinal rods in the frame is 4-6 pcs. For a square section, four rods at the corners of the element are sufficient; for a rectangular shape, the long side is additionally reinforced. Cross-linking of reinforcement is used when arranging columns up to 2 meters long.
A frame exceeding a length of 2 m is tied with short rods across, with a step of 20-50 cm, taken when calculating according to the planned load.
The capitals are reinforced with a reinforcing mesh.
The thickness of the mesh rod is taken from 15 mm, the mesh size is 10 x 10 cm.
The reinforcement of the sub-column is carried out by laying the mesh in each step, the size and number of the mesh is taken from the project.
Concreting
After the installation of the formwork and the reinforcing cage, they proceed to concreting, which produce layer by layer, in layers with a thickness of 0.3-0.5 m, preventing the setting of the previous layer. Do not add 50-70 mm mortar to the top of the formwork.
For shrinkage of concrete in columns above 5 meters, suit technological breaks from 40 minutes to 2 hours.
With mechanized feeding of ready-mixed concrete, the feed rate is reduced to avoid delamination. Air is released from the mixture with steel rods, concrete compacted with hand vibrators... In places inaccessible to the vibrator, concrete is compacted manually, by careful bayonetting.
Upon completion of work, produce seasonal care behind the concrete.
Dismantling the formwork
Duration of concrete set to 100% of working strength is 28 calendar days... The indicator may vary from environmental conditions - temperature, humidity, complex of care works. The average period of standing of monolithic columns before stripping is 7-10 days in summer. This period allows the corners and side faces to form.
note
Column concreting
The column is a supporting engineering structure, which, in addition to its practical function, also serves as a decorative purpose. Today, columns to ensure the vertical rigidity of the building can be made of metal or reinforced concrete.
In turn, reinforced concrete structures are most widespread due to various kinds of advantages. For this reason, when making columns with your own hands, the greatest preference is given to concrete products. How the columns are concreted will be described below.
Column concreting
It should be said right away that making concrete columns with your own hands is a laborious and costly process, both physically and financially. Before you start making reinforced concrete columns, you should study the appropriate technology as much as possible, watch a video on the Internet and prepare the tool necessary for this work.
Then you need to decide on the shape of the future column, since it can be: round, rectangular, or square. Of the tools for the manufacture of columns, first of all you will need:
- Building level;
- Plumb line;
- Hammer and hacksaw for wood;
- Bulgarian;
- Roulette;
- Concrete mixer;
- Shovels and other devices for working with mortar.
Of the materials you will need:
- Formwork boards;
- Rebar (12mm) or metal mesh;
- Knitting wire;
- Anchor bolts;
- Clamps.
Do-it-yourself column construction is divided into such stages - reinforcement, formwork installation and concreting of the assembled structure. Let's take a look at each of the above steps in order.
Pouring concrete columns with your own hands
For reinforcement of concrete goods of columns, reinforcement of at least 12 mm is used. Even before starting the assembly of the formwork, a metal frame is assembled in the shape of a square, consisting of four main rods in the corners. If the column will have a height of more than 3 meters, then special blind areas are necessarily made every two meters.
When the column has a small height, the metal frame can be installed in a pre-assembled form, immediately into the formwork, after its installation. The fittings are fastened to each other either with a knitting wire, or with special clamps designed for these purposes.
Formwork for concreting columns, as a rule, is assembled from boards, according to previously measured internal dimensions. It is necessary to take into account the large load on the formwork when pouring concrete, therefore, it is necessary to unfasten the boards very carefully during its assembly.
Be sure to install slope supports from the sides of the assembled formwork, before pouring it with concrete. If the column will have a large height, then its build-up is carried out during the pouring of concrete, and also with the obligatory installation of slope struts.
Concrete for pouring columns is not used the same as, for example, in the construction of a monolithic foundation. Its main parameter in this case is mobility. For most columns, a concrete solution with a mobility of P2 is used, and when pouring densely reinforced ones, concrete with a mobility of at least P4 is used.
An important process in the concreting of columns is the compacting of the concrete mixture, which is produced by such specialized equipment as submersible and external pumps. When making concrete columns with your own hands, tapping the walls of the formwork with a hammer allows you to get rid of air plugs in the concrete.
In the process of concreting the columns, it is necessary to monitor all the time whether the metal frame has not shifted inside the installed formwork. If necessary, you should correct its location strictly vertically and in its center.
Do-it-yourself concrete for pouring columns consists of cement grade not lower than M400, sand and gravel. If we talk about its proportions, then they look as follows - for 1 part of cement, 1 part of sand and 4 parts of gravel are required.
samastroyka.ru
How to make concrete columns with your own hands?
Columns in the building system perform both a decorating function, that way and an actual one - they are considered the principal bearing component of the structure. And since, according to the default, it is expected that the supports will be heavily loaded, then naturally they must exist made in maximum compliance with all existing generally accepted standards and rules. In this note, we will tell you about how concrete columns are poured correctly, as if it is important to take into account here and that it is categorically not recommended to work. These systems are divided, before that only, into these main groups: Round; Rectangular;
Since we will not look at the installation of finished products, but we will talk carefully about the device of monolithic supports, we should be guided by the claims to such supports. the object on which the supports are installed; The purpose of the object - since the degree of the forthcoming overload on the columns directly depends on this; Type of soil at the facility; Climatic individualities of the region where the construction is being carried out. We recommend: in order to make a truly benign reinforced concrete support, you should familiarize yourself with the information contained in GOSTs. Columns in the building system perform as a decorating function, that way and an actual one - they are considered a fundamental bearing component of the structure. And since, according to the default, it is expected that the supports will be heavily loaded, then naturally they must exist made in maximum compliance with all existing generally accepted standards and rules. In this article we will tell you about how concrete columns are correctly poured, as if it is important to take into account here and that it is categorically not recommended to work. These systems are divided, before that only, into these main groups: Round; Rectangular;
Since we will not look at the installation of finished products, but we will talk carefully about the device of monolithic supports, we should be guided by the claims to such supports. the object on which the supports are installed; The purpose of the object - since the degree of the forthcoming overload on the columns directly depends on this; Type of soil at the facility; Climatic individualities of the region where the construction is being carried out. We recommend: in order to make a truly good-quality reinforced concrete support, you should familiarize yourself with the information that is contained in the GOSTs. In these documents, it is allowed to find general information about the correct production of concrete products and columns in particular. In principle, we have finished with the overview of the products, you can skip directly to their production and pouring. Finally, a short step-by-step annotation on the installation of supports for buildings. Before that, before starting, it is worth noting one fundamental point - we will look at the most common assembly method, which can be easily implemented without the help of others. When building a personal building, for example. Publishing a review on self-pouring of pillars for the construction of a plant does not matter in any way, you must agree. At least because everything alone cannot cope with such an object in the same way - you will have to attract a lot of highly qualified professionals who themselves understand how similar tasks are performed. 23009-78, 18979-90, 25628-90 and 23899-79. In these documents, it is allowed to find general information about the correct production of concrete products and columns in particular. In principle, we have finished with the overview of the products, you can skip directly to their production and pouring. Finally, a short step-by-step annotation on the installation of supports for buildings. Before that, before starting, it is worth noting one fundamental point - we will look at the most common assembly method, which can be easily implemented without the help of others. When building a personal building, for example.
Publishing a review on self-pouring of pillars for the construction of a plant does not matter in any way, you must agree. At least because everyone cannot cope with such an object in the same way - you will have to attract a lot of highly qualified professionals who themselves understand how similar tasks are performed.
rusbetonplus.ru
Forms for pouring columns: self-production and installation
Columns are increasingly used in the architecture of facades and interiors. This is not only a beautiful decorative element, it is also a practical, utilitarian piece of construction.
It allows you to support slabs or beams without taking up much of the usable area of the lower floor.
The column can be bought ready-made, but it is more convenient and cheaper to make it yourself. The easiest way is to lay it out of brick, but a monolith is much stronger and more reliable, and for its manufacture you will have to make a formwork.
According to the method of use, they are non-removable, disposable and reusable. They are made of metal, wood, plastic and even cardboard.
- Metallic. Usually reusable. These are convenient ready-made shields that are easy and quick to assemble, provide the correct geometry, and are quickly dismantled.
- Wooden. Usually self-made, reusable. Get knocked out of planks and bars. Cheaper, but more difficult to achieve the correct shape, especially one other than a rectangle.
- Plastic. usually round shapes are made. You can buy ready-made ones, or you can make a formwork from plastic pipes of a suitable diameter with your own hands.
- Cardboard. are made of dense cardboard impregnated with special adhesives. The form is only cylindrical, such formwork is exclusively disposable.
Ready-made formworks are offered by many manufacturers, however, they can be made independently, given some of the features of this construct.
Peculiarities
The column is small in width and thickness, but often has a significant height. This determines the rather specific loads on the form.
The formwork is under significant pressure at the bottom and very little at the top.
The elongation of the form in height makes the structure very unstable, it can easily collapse, so the formwork requires several supports.
Also, the form must have rigidity so as not to fold, not to bend under the weight of the concrete.
It is assumed that the column will work in compression, so it is extremely important to avoid distortions of the structure. If the form bends in an arc, then the support made in it can easily crack under load. The column withstands bending loads very poorly.
It is very important to clearly maintain the vertical level. Even a slight deviation from the vertical creates an imbalance in the loads that can lead to failure of the entire structure.
- First, the size of the future columns is determined.
- Boards are being prepared that will act as forming surfaces - they are adjusted to the size of the pillars, sanded from the side that will contact the concrete.
- Crossbars are nailed to the boards - small bars that will serve as stiffeners.
- Separate boards with bars are knocked down into forms for pillars. Especially tightly you need to connect the part that will be at the bottom of the column.
- The reinforcement is embedded in the mold and the entire structure is installed at the place of the column installation.
Then a frame is made of reinforcement with your own hands.
Since the posts are square, it is most convenient to take four vertical rods, tying them together with short crossbars made of soft wire.
In order to make the boards easier to remove later, they can be upholstered from the inside with oilcloth. To assemble the form, you need to choose flat boards so that the posts do not have bends, curvatures.
It is worth remembering that this is a disposable formwork for columns; after the concrete has hardened, the cardboard will have to be ripped off like wallpaper from the wall.
The easiest way is to make the formwork in a mesh frame. First, a steel mesh with square meshes is taken, which is not prone to stretching.
It is rolled up into a cylinder of the required diameter, securely fastened in this position by wire or welding.
Then rolled cardboard is placed inside, which, after stacking, straightens and rests against the grid. Finding sheets of cardboard for 2-3 meter posts is not easy, so you will have to use several sheets, fastening them between the overlap with adhesive tape.
The construction turns out to be very unstable, therefore wooden supports are required.
Such a disposable formwork is suitable for round columns, rectangular or square cannot be poured in any way.
You can do it yourself with a fixed formwork made of expanded polystyrene.
This option is used for facade work, it allows you to get very flat surfaces, uniform with walls insulated with foam plastic.
However, this fixed formwork is not strong enough and therefore also requires a supporting frame.
Steel mesh will cost 20-25 rubles per square meter, thick cardboard - 200-250 rubles per roll. Polyfoam will cost 1000-1200 rubles per cubic meter.
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Column formwork: types and solutions
Today, round concrete columns are very often used in construction, which serve as supports for large terraces, small balconies and upper floors. In order to erect a column, it is first of all necessary to build a formwork, plastic, cardboard, etc., into which the concrete solution will be poured. This design can be reusable or disposable. Each of them has its own advantages and disadvantages. About them and how to make a frame for a column with your own hands will be discussed further.
Reusable formwork is a frame that can be used a large number of times in work. Such a structure is usually assembled directly at the construction site and concrete is poured into it. After the concrete solution dries a little, the formwork is removed and used in other works. The disadvantage of this design is that the round columns may not come out in one piece, since often the height of the frame does not coincide with the desired height of the finished structure. In this case, the formwork has to be put on several times.
It makes no sense to buy your own reusable design, since it will be used very rarely at home. It is best to rent it. The cost of a reusable frame will depend on many factors. Among them, the material for the manufacture of the structure, the cost of its proper conservation, maintenance and transportation to the construction site. In addition, you need to calculate the costs of the mechanisms with which the formwork will be lifted.
Round column formwork, which can be used several times, is divided into several types:
beam;
steel;
plastic.
The girder structure allows you to create columns of almost any height. It can also be used for the construction of bridges, walls and any vertical structures, even very large ones. The beam frame is assembled with your own hands like a designer, after which it is reinforced with spacers. Steel formwork is also very good for round columns, but it needs to be lubricated with special mixtures after each use. Considering that the steel frame has a fairly large weight, it is possible to work with it only with the help of special lifting equipment.
Plastic formwork for columns (see photo) is not as heavy as the previous one, but also not as reliable. It is recommended to use it carefully so as not to damage the material. Individual elements of plastic are interconnected by small parts, which you need to do with your own hands very carefully, because otherwise, under the pressure of the solution, the structure may simply fall apart. The advantage of this frame is its low price.
The use of a non-removable structure
Fixed formwork for columns is not used so often today, because it requires a special approach. To create it, a solution of cement, sand and water is prepared, which is passed through a special machine, from where ready-made frames of the required shape come out. Such products have thin, but at the same time very strong walls. This becomes possible due to the compaction of the mixture and the displacement of almost all of the liquid from it. As a result, the frames become not only very durable, but also resistant to excessive humidity, frost and strong temperature changes.
Construction at one time
Today, the cheapest and most practical formwork for columns is disposable, made of cardboard. It represents a cardboard connected in a spiral, which is processed with a mixture that repels water (see photo). The inside of the formwork can be covered with a polyethylene film. The cardboard structure for creating round columns can have a diameter of 25 centimeters to 1.1 meters, and its length is usually about 11 meters. Depending on the diameter and height of the frame, the thickness of its walls may vary.
Column formwork is very easy to install. To install it, no additional equipment and tools are required. Thanks to this, all work can be easily done by hand. To begin with, the formwork must be placed vertically and carefully attached to the floor. From above, the structure can be fixed with anchor rods. Further, the inside of the formwork is poured with concrete, after which the cardboard is carefully separated from the concrete. This can be done using a special rope, pulling on which you can divide the frame into two parts (see video).