Filling the formwork: which structure is better. Do-it-yourself foundation formwork: step-by-step recommendations on how to make formwork We mark the formwork under the foundation with our own hands

Installation of floor formwork can differ in different parameters, which is characterized by the type of product and the peculiarity of the work. In this article we will consider the types of formwork for floors, and also describe detailed instructions for installation.

Types of products for overlap

All work on the installation of floor formwork is intended for the construction of buildings or houses in a monolithic way. When carrying out work, it is important to adhere to the rules and recommendations in order to ensure the strength and stability of the structure. The formwork installation technology must be carried out by workers or specialists in this field.

Before proceeding with the installation of floor formwork, it is important to consider the parameters and types of this type of product. There are such types of structures:

• on wedge forests;
• formwork on cup scaffolding;
• on volumetric bowls;
• formwork on telescopic racks.

For telescopic racks made of steel, formwork is used when the ceiling height is no more than 4.6 meters. When erecting a structure of greater height, it is important to use bulk formwork. In this case, the installation is intended for monolithic slabs made of reinforced concrete with a height of 20 meters and a thickness of up to 70 cm. For this type of formwork, it is necessary to use vertical posts, inserts, jacks, crossbars and other connecting elements. All assembly and disassembly work is not complicated.

The peculiarities of installing telescopic slab formwork are to fix the tripod in the base, which supports the entire structure. At the same time, the installation technology is carried out using special shields. They are made of plywood, which is waterproof. In fact, plywood panels are essential items for assembling formwork.

A different type of construction is carried out on wedge scaffolding, which are used for the installation of floors of a multi-storey building. They can be used for other purposes, however, instead of plywood, scaffolds are laid on them and ladders are fixed, which is necessary for lifting workers. Wedge scaffolds have a prototype design, which consists of horizontal and vertical racks. They can be connected at different angles, which will allow you to perform efficiently on difficult sites.

The technology for installing floor formwork on cup scaffolds consists in installing a structure in the form of a frame. This method differs from the previous one in that the variant of connecting the racks must be done by the cup method. This will allow 1 to 4 pieces to be placed on one level in 1 bowl.

Features of the assembly of formwork for beam floors

The technology for the installation of floor formwork involves the use of beams made of reinforced concrete. They carry out the main load of the building. Therefore, formwork is important not only for the floors, but also for the beams themselves. Work should be started after the completion of the installation of the columns.

First of all, the beams are fixed in special grooves, which are located in the formwork structure of the columns. After that, you can start installing telescopic racks, however, it is important to remember about the permissible heights. All support elements are recommended to be installed on tripods, which are fastened with crossbars, which will increase the stability of the beam floor.

Next, proceed to the installation of the walls of the formwork, which is important to fasten together and the bottom, using special fasteners. An additional element of strengthening is the flooring of wooden beams. It is also important to install telescopic props for slab formwork under them. The last stage of work is the installation of panels on the sides of the formwork and the laying of a reinforcing frame. In this case, it is necessary to additionally check the following aspects:

• the final procedure for adjusting the formwork;
• checking the level of floor beams and other elements;
• establish the presence of sags or deflections, which are important to eliminate.

Features of installing formwork without monolithic beams

The formwork installation scheme using this technology can be compared with the features of the installation for a beam floor. However, this method is simpler, since there is no need to install additional fences, they are intended for casting monolithic beams. You should know that for the assembly of the formwork, it is important to adhere to the requirements and rules that determine the installation distance of the support posts.

• The installation step should be no more than 2 meters if the ceiling height is up to 230 mm.
• A step of 1.7 meters is used for floors with a thickness of 28 cm.
• If the overlap is about 320 mm, then it is advisable to put the racks every half a meter.

During installation work, it must be remembered that the distance between the racks described above has the maximum values. Therefore, it is recommended to slightly reduce the step between the supports. Plywood, plastic and other building materials can be used as shields for the construction of floor formwork. It is important to know that in order to obtain a good quality surface, it is important to use laminated products. If plywood is planned to be used, it is important that it is moisture resistant.

Features of installing polystyrene foam formwork

This installation scheme has some nuances that are important to remember when installing the formwork. The design scheme is designed for specific cavities, which are designed to form reinforced concrete bearing beams. This will reduce the amount of work. At the same time, in all the details of the formwork there are special niches through which you can lay various communications, such as sewerage, water supply, electricity.

An approximate scheme for creating formwork for monolithic floor from expanded polystyrene does not present certain difficulties, so that 2 or 3 people can participate in the work process. Installation technology is advised to start with the installation of racks and supporting beams.

It is important to know that the direction of the beams should be perpendicular to the position of the panels and to the perforated metal profile, which will enhance the bearing capacity. If you need to carry out the necessary communications through the formwork, then you can cut an opening in the wall, while the joint area is important to seal.

Features of dismantling work

The parameters for the dismantling of the formwork may depend on various factors, which are determined by some regulatory and design documents. In this case, the deadlines depend on some factors:

• the brands of concrete used;
• the time of the year when the installation work is carried out;
• overlap thickness and parameters.

As a rule, in summer it will be possible to remove the formwork after 3 or 4 days, but it is recommended to continue construction work only after 3 weeks. In winter, the drying time of concrete is extended, depending on damp and cold weather. The essence of dismantling the formwork is the simplest disassembly of parts. If the design has special falling heads, then the dismantling process is greatly simplified.

Also, the use of such parts will allow partially to carry out the work, but it is possible to simultaneously remove the floor formwork, the photos of which can be seen on this site. You can determine the time to remove the structure if you calculate the level of concrete strength, the indicator of which should be from 70 percent.

How to make slab formwork: step by step instructions

In a similar situation, we will consider the features of the construction of formwork for monolithic floors. They are often used in current construction. If in the process of work use quality materialsmade by the latest technology, then this will reduce the weight of the structure, load parameters, which will reduce waste on construction.

High-quality work performance ensures correct installation formwork, because pouring and forming the foundation is not a complicated process. As a rule, builders use several options for using formwork, some of which offer to purchase a ready-made structure, and the latter prefer to do everything with their own hands.

It is important to know that the formwork for the floor slab is made by this method: the frame is assembled from vertical racks, which are fastened together with special beams-crossbars. They are nailed perpendicularly to the transverse beam on which the plywood flooring is laid. It must be laminated and moisture resistant, which forms the bottom of the formwork. To carry out the work, it is necessary to prepare the following materials:

• support posts, which are bars with a cross section of 120x120 mm up to 150x150 mm;
• crossbar and transverse bar - has the form of an edged board, the section of which is 160-180x50 millimeters;

• braces, which represent a board that has a thickness of 3 cm;
• flooring, moisture-resistant plywood is used, the thickness of which is 1.8 cm.

For such work, it is not necessary to purchase expensive materials made of coniferous trees, which is very uneconomical, therefore, several alternative options can be distinguished:

• use lumber that is intended for the rafter system;
• use previously used products that were previously used in construction;
• preference for materials that are made from low-grade tree species, such as soft-leaved ones.

To carry out the work, you need to make a calculation of the floor formwork, namely, to install the required number of supporting elements, which are the racks. So, when assembling the formwork, it is important to consider the post placement steps. All parameters and distances have been specified in this article.

Step-by-step instructions for installing the formwork:

1. Given the thickness of the floor, we recalculate the steps between the beams, thus forming the first row. To do this, you need to drive a longitudinal bar into special grooves with nails into the upper ends of the support posts. The approximate half-groove depth should be the same as the ledger. This will provide the correct support load. Further, we fix the ends of the longitudinal bar to the wall.

2. In the same way it is necessary to assemble the second row for formwork. The base for the structure must be solid and level. To do this, it is advised to put the board under the supports, the thickness of which should be about 5 cm.

3. Attach a cross bar perpendicular to the longitudinal bar with a set distance of 60 cm. Next, install the support posts, the verticality of which is checked using a plumb line.

4. Using the same technology, you need to install the rest of the rows to create a frame of the required parameters.

5. It is important to level the horizontal beams using the building level, and the height of the posts is easy to adjust.

6. It is important to fasten all the racks together using braces. They can be attached with nails, while their position should be diagonal. At the same time, you need to ensure that the entire frame of the racks is strong and reliable enough for further work.

8. It is important to keep the ends of the floor from freezing. Thus, along the perimeter, you need to make masonry, for example, from aerated concrete blocks. For brick walls, it is necessary to lay out four rows of brickwork, the thickness of which is 12 cm. And the outer side is recommended to be insulated with foam.

10. Carry out the fill concrete mortar... It is recommended to dismantle the formwork after 20 days.

The formwork installation scheme for different types of slabs represents the implementation of a large amount of work, the implementation of which will require huge costs. Of course, the formwork can be built with your own hands, or you can purchase a new structure. In this case, all costs will be the same.

Slab formwork: assembly instructions, Construction portal

Construction of houses Installation of floor formwork can differ in various parameters, which is characterized by the type of product and the peculiarity of the work. In this article we will look at

The construction of any monolithic objects, be it a residential building or an industrial building, is not complete without wall formwork. This structure is necessary for the construction of walls and floors.

Manufacturers offer many variations to solve problems of any complexity, one of the most popular is the Gamma series formwork.

Formwork material

An important characteristic is the material from which the wall formwork is made. The calculation of the required amount of concrete depends on this, as well as its weight, strength, cost, installation and finishing. Formwork is made from:

reinforced concrete;

Each of the materials has its own advantages and disadvantages. Metal formwork is widely used in industrial construction (withstands high casting speed). However, at the same time it is very heavy, its installation requires the use of special equipment.

The form of expanded polystyrene is light, serves as an additional insulating layer. However, the low strength of the material complicates construction (for example, a concrete pump cannot be used for pouring).

Wood, chipboard and plywood are also easily deformed, but at the same time provide easy and quick installation. Plastic is sensitive to negative temperatures, but durable and sealed. The main area of \u200b\u200buse is private construction (if you need to make a shallow foundation or a light building with your own hands), because their installation does not require special skills.

Large developers prefer to work using removable structures, which also include Gamma formwork. Depending on the purpose, it can be used to build:

round structures (columns, pillars);

overlaps.

The calculation of the required volume of concrete is based on the type of formwork.

Advantages of removable structures

If we are not talking about one-time construction, prefabricated large-panel or panel formwork - the best option, thanks to such advantages:

Versatility. Components (special fasteners, rotary elements) allow you to create structures with complex shapes.

1. Installation of removable formwork

   The main components are a block and fasteners (). Depending on the type of structure (panel board, large panel board), the block can be from 90 * 60 cm in size, and up to 330 * 120 cm. The calculation of the required size of the panels is based on the scale of construction. For construction small house, or ordinary panel formwork with blocks of 1.5 * 1 m. is the best option.

   Panel formwork is easily assembled with your own hands, installation does not require the use of special equipment, and various components allow you to assemble a structure of any shape. This makes it indispensable for pouring a foundation or erecting walls and floors of a one-two-story building.

   The frame of the shield is made of metal profile (high carbon steel or aluminum alloy). Shield - plastic or plywood, in some cases finishing with reinforcing material is provided. The installation of additional stiffeners guarantees the strength of the structure.

   A significant advantage of the non-removable form is its cost and easy installation. The construction of monolithic houses with this design allows you to minimize labor costs. Installation of other structures consists of the following stages:

   • a corner block is being mounted and walls are being erected;
   • installation of door and window openings is in progress;
   • concreting is carried out (each stage of pouring is performed after the previous layer has solidified).

   Features of large-panel formwork

   The large-panel formwork Gamma has, in addition to the listed elements, the following components:

   

   an inner corner to make a corner block;

   hinged shields with which you can form internal and outer corners any radius;

   arcuate element, to obtain a rounded section of a wall or floor;

   screeds that rigidly fix the shields to each other.

   Also, to facilitate work at a height, the set can be supplied with a platform for workers, which can be easily attached to the block at the level of any floor. Components can be purchased as needed, the calculation of the required amount will be done by specialists.

   Large-panel formwork is used in the construction of large-scale objects, therefore, special requirements are imposed on it. The block must be able to withstand the high casting speed and its rigidity must ensure the ideal geometry of the walls and foundation. This is achieved through the following design features:

   solid-rolled profile shield;

   a special lock that allows you to insert additional sheets between the boards, up to 10 cm thick (for strengthening the structure or additional heat and waterproofing);

   fasteners simultaneously pull and fasten the shields together;

   the block is covered with a special, protective coating ( powder paint), this exterior finish helps prevent corrosion.

   Today Gamma movable removable formwork is the most optimal solution in terms of price-quality ratio.

   Application of wall formwork (video)

   Choice of formwork for various objects

   They are mainly used in the construction of the foundation of small objects (cottage, garage) with their own hands. Installation in the trench and pouring is done manually. For heavy structures, the foundation and walls are reinforced with reinforcement. External and exterior decoration possible immediately after the concrete has set.

   Permanent panel formwork made of expanded polystyrene has become a popular solution for the construction of small private houses. The thermal insulation properties of expanded polystyrene can significantly save the cost of heating the room. In addition, the decoration of such a building (both inside and outside) is not particularly difficult. Most finishing materials (plasterboard, facing plates, lining, veneer) are easily attached to expanded polystyrene sheets.

   A removable panel formwork can be installed to build a shallow strip foundation, in which case it acts as a basement. Wooden or - an optimal solution for the price, since a shallow foundation does not imply the use of complex structures. It is easy to assemble and disassemble it with your own hands, using the tools at hand.

   Large-panel formwork (for example, Gamma 330) is used in the construction of multi-storey buildings, industrial facilities etc. At the same time, due to its configuration, it is easily transformed into a form for floors, supporting elements. The accompanying documentation indicates possible assembly schemes and the calculation of the necessary elements.

A well-prepared pillow and excellent quality concrete are worth nothing if the foundation formwork is very poorly made. It is clear that the accuracy of the geometry of the base plate or tape depends on many factors, but first of all on a serviceable and strong frame for pouring concrete. Therefore, in addition to normal cushion, concrete and reinforcement for installing formwork under a good quality foundation, most likely, you will need to buy a normal sawlog and not collect slabs from the nearest storerooms, even if it is a disposable formwork.

Basic elements of formwork under the foundation

The standard device for casting a foundation involves the use of the following materials:

• Marking cords and stakes, guide boards. Boards and stakes will need to be sewn to the pillow at the bottom of the trench, after which you can install side shields and fasteners for the foundation formwork;
• Edged board, at least 30 mm thick, and a bar with a section of 50x50. The amount of lumber required for the assembly of sideboards is calculated based on the depth of the foundation, the width of the tape and the size of the perimeter;
• Side braces, supports, struts and ties for foundation formwork, studs, plastic wrap, steel corners and nails are bought with a margin, it is better not to use old illiquid assets.

For your information! The best fasteners for wooden formwork are ordinary hardened self-tapping screws, 35 to 70 mm long. They are more expensive, but the quality of fixation is much better, especially since the danger of splitting the board or plank is excluded.

If you decide to install the formwork under the foundation on self-tapping screws, stock up on an electric screwdriver and a pair of replaceable batteries, and the supply of self-tapping screws can be rinsed with kerosene, this will help to properly fix the material without distortions in the wood.

Forget laminated chipboard and steel tubular frames, this type of reusable formwork cannot always be installed correctly on your foundation. If you liked a steel, aluminum or plastic frame, then immediately hire a team of workers who can properly assemble and install it according to your requirements.

Correctly assemble and install the foundation formwork

In the overwhelming majority of cases, builders prefer to assemble side shields, struts, bring the entire set to the foundation trench, and only then assemble - install the finished parts according to the markings made.

The best option would be the following order of work:

Transfer all the characteristics and dimensions of the future foundation to the exact formwork sketch, if necessary, check the dimensions of the trench and correctly increase the width at the places where the struts are installed:

1. Assemble the side shields from the edged board. For conventional formwork under the MZLF, you will need to install a shield 60-70 cm high. Length at correct selection the material does not strongly affect the quality of the formwork and, as a rule, depends on the possibilities of transport;
2. We cut the spacers from the bar and mark the places for their installation on the boards, in the foundation trench the notches will help to correctly install the bars so as to withstand the required width of the tape;
3. We make required amount struts, they will need at least one pair per meter of shield length.

For your information! In some cases, craftsmen prefer to make and install struts directly when installing side panels in a trench.

There is not much left - to hammer in the support stakes according to the markings, install the shields and fix them correctly, taking into account the readings of the building level and the plumb line.

How to put the foundation formwork on the ground

The most important stage in the installation of formwork has always been and remains the process of adjusting the position of the posts and panels relative to the marking lines. First of all, along the stretched cords, you need to install and hammer in a number of marking stakes, better made from scraps of the board used to assemble the side shields. A flat peg is cut at least 20-30 cm longer than the vertical posts of the side formwork panels.

Each such stake must be installed at the bottom of the foundation trench, while the lateral plane and the height of the stake are aligned in the direction of the marking line and the vertical plumb line. It is necessary to install the marking stake very reliably, if necessary, make an external support.

For your information! It is very important to correctly install and securely fix the marking stakes, all further assembly of the formwork is done quickly enough.

The next step is to install external formwork panels. On the outside, the shields will rest on marking stakes, on the inside, you will need to install temporary fasteners from the same pegs, hammered in a checkerboard pattern with marking stakes as in the photo. After leveling the boards with self-tapping screws, we grab them to the marking posts.

Next, we install the inner perimeter of the side shields, temporarily fix the inner row with spacers and struts. We check and adjust the position of the boards according to the building level, the stretched marking cords and the vertical plumb line, after which we connect the upper boards of the neighboring boards with strips.

Final operations

After customization and fitting individual elements formwork for the marking and dimensions of the foundation, another important element will need to be completed - to fix and strengthen the base of the side formwork panels. It is on the lower part of the side surface that the maximum expanding load falls, therefore, each shield from the bottom, from the outside, must be hemmed with a bar or a bottom board, it is advisable to do this even at the stage of assembling the panels, since it is not very convenient to hit the nails at an angle, unfolding in the trench ... Installed struts, as a rule, hold the sides, but do not prevent the bottom from deforming, so it is vital to install wedges in the bottom.

Wedge-shaped pegs are driven into the ground every 60-70 cm along the hemmed bottom board, their task is to fix the bottom of the formwork and prevent the boards from dispersed under the pressure of concrete.

At the final stage, experts recommend covering the wooden formwork with plaster or covering it with thick plastic wrap. A correctly laid coating will protect the formwork tree, less water will be absorbed, and after the concrete has set, it will be quite easy to remove the boards.

Pouring concrete, lining boards and removing formwork

The integrity and resistance of the formwork to hydraulic loads from liquid concrete largely depends on the ability to accurately pour the concrete solution into the mold. It is possible to correctly regulate the pouring process by rearranging the guide grooves along which the solution flows into the mold. The main thing is that after pouring the foundation, the solution should flow evenly throughout the formwork, gradually increasing the level of the filled mass.

Sometimes a situation arises when the lower and middle boards are bent under the pressure of concrete. There is no disaster in this, if this does not affect the overall dimensions and position of the formwork, although, according to all canons, such a defect must be eliminated. If there is a threat of board tearing or deformation of the entire plane of the shield, then urgent measures must be taken to strengthen the surface and a specific board. Firstly, additional screws are cut in and the reinforcing struts are correctly installed. Secondly, it is necessary to wrap or hammer a pile half a meter from the place of the bend, install a car jack horizontally, and through a steel plate or thick wooden board gently press down on the defect. It will not be entirely correct to summon all those present to help, there is little sense from them, one competent assistant with a jack and a pile is enough.

It will be correct to remove the formwork after pouring for the strip foundation in a week at an average air temperature of at least 15-17 ° C, in cold weather the period before disassembly must be doubled. In order to properly disassemble the structure, you will first need to remove the struts, pull out the wedges along the bottom board and knock down the upper planks that tighten the shields. If a film or roofing material has been laid, it is enough to carefully drive a few wedges into the gap between the shield and the foundation tape.

Conclusion

All wood formwork options are built according to the same scheme, therefore, having mastered the most complex tape option, you can without hesitation, correctly assemble and install the form for piles, MZLF or slab foundation... The biggest problem when assembling a form of any type of foundation will be the problem of correctly assembling a structure for steps, a furnace or an extension of a complex structure. Any of the listed elements will take a lot of time to come up with and install the frame of the desired shape and size.

Confirmed by many decades of observation, research and technology refinement.

The construction methodology of this type of foundations has been worked out to the smallest detail, which makes errors unlikely.

All possible problems arise only with the independent construction of the foundation by people who do not have experience and appropriate training.

Most of the mistakes are made at the preparatory stage, when creating belt structural elements.

Consider one of the important stages of construction - the assembly and installation of formwork.

Formwork is a form for pouring concrete. It is a panel structure made of wood, plywood or polymeric materialsforming a container in the shape of a concrete tape. It is built directly at the casting site, according to the dimensions specified in the project or working drawing.

In most cases, the exhibition is made from edged boards, but there are also more specialized designs designed for reusable use. The main requirement for formwork is strength, the ability to withstand the loads that arise when concrete is poured and hardened.

In addition, the tightness of the form is important, which prevents the flow of concrete and excludes unproductive loss of material.

Views

There are different types of formwork.

They differ in the type of construction and installation:

• Small and large panel... The most common type.
• Blocky.Used to fill wells, columns, etc.
• Volume-adjustable... Used for parallel casting of vertical and horizontal surfaces.
• Sliding... Moves as the concrete sets for further pouring.
• Horizontally movable... A type of sliding formwork for pouring horizontal structures.
• Lifting-adjustable... It is used for tier concreting of vertical structures.
• Fixed... Concrete or expanded polystyrene blocks are used, from which the wall is assembled, and the inner cavity is filled with concrete. The technology is relatively new and not yet widely adopted.

Of the listed options, panel types are mainly used, since the remaining structures are intended not so much for a strip foundation, but for general construction work.

There are varieties according to the level of heat saving:

• Insulated.
• Heating.
• Special.
• Uninsulated.

The choice of the type and material for the formwork is made at the stage design work and is based on engineering calculations.

Most private house projects consider only wooden formwork due to the ability to assemble any size, but there are other solutions.

What material is used

Formwork can be created from various materials:

• Wooden.
• Plywood.
• Made of expanded polystyrene.
• Metallic.

In addition, there are options in synthetic fabrics or rubber. Wooden structures predominate, since they are cheap, they can be used repeatedly and in different sizes.

Reusable molds are designed for mass production of castings of the same size and configuration, so they are made from materials that are stronger and more durable.

The advantage wooden structures is low cost and versatility, but the assembly time is much longer than that of plywood or metal finished panels.

How to calculate the quantity?

The simplest way to calculate is using an online calculator. You enter your own data in the corresponding windows - the height of the tape, the total perimeter multiplied by 2, and the type of material.

The result is the amount of wood in cubic meters. This is convenient, since the usual calculation is made by area, which is then converted to cubic meters.

For those who do not trust the online calculator, the calculation method is useful:

1. The perimeter of the tape is calculated.
2. Divided by the length of one board, we get the number of shields.
3. The width of the shield is selected according to the height of the tape (usually a multiple of the width of the boards).
4. The number of boards in each board is calculated.
5. Multiplied by the number of shields.
6. The result is multiplied by 2.

In addition, you need to calculate the number of planks required to create crossbars and stops. It is determined by the product of the total number of shields by the number of strips of one shield.

NOTE!

Any calculation method is approximate enough, therefore it is recommended to purchase 10-15% more than it turned out when calculating.

Which board is best to use

For the assembly of formwork, the most common material is usually used - edged pine board. It is recommended to plan the working surface of the boards, but this is not always possible, therefore most often the boards are assembled from unplaned boards.

An important issue is the moisture content of the lumber. In this case, the use of a dry board is not necessary, and sometimes even undesirable. For a long time, the formwork keeps the massif moist, which is periodically watered all this time.

Dry lumber begins to actively absorb moisture, swells and increases in size, which is why individual boards are squeezed out of the plane by the shield a.

The thickness of the boards used for the assembly of panels ranges from 25-40 mm. The higher and wider the tape, the thicker the boards must be in order to withstand the loads during pouring and the pressure of liquid concrete on the walls.

Installation procedure

The formwork is created in stages.:

1. Vertical cross bars are cut... Their length is 40-50 cm higher than the calculated width of the shields, since they have to be driven into the ground. For this, one end is sharpened for better entry.
2. Preparing the boards... They are cut to length (if necessary) and stored on a flat surface. Optimally - close to the trench so that you don't have to carry ready-made shields over long distances.
3. Lay out the crossbars with a step of 0.8-1.2 m... The upper cut is aligned with the line.
4. Assemble shields... First, attach the top board, then attach the rest as tightly as possible. Nails or self-tapping screws are used.
5. Shields are lowered into the trench, aligned in axes and dimensions... The pointed ends of the vertical planks are driven into the ground until the horizontal planks come into contact with the bottom of the trench.
6. Parallel shields connected by crossbarsdetermining the thickness of the tape. Their role is sometimes performed by U-shaped clamps assembled from wooden bars.
7. From the outside additional inclined spacers are installed, excluding the extrusion of panels when pouring concrete.

The inner surface of the formwork should be covered with plastic wrap to ensure tightness and prevent concrete leakage. No matter how neatly and tightly the formwork is assembled, the loads during pouring are very high and arise abruptly... The shields diverge slightly, which leads to the appearance of gaps. The film saves material and prevents waste.

Installation of removable plywood formwork

Plywood allows you to get sealed panels with a flat and smooth surface. For one-time you can get by with the cheapest pine plywood, but for reusable formwork, it is recommended to choose a more durable birch plywood, impregnate it with drying oil or purchase film faced plywood (the best option).

The thickness of the sheets is chosen based on the height of the formwork, but not less than 10-12 mm. Plywood of 14-18 mm is usually used.

Assembly order:

1. Plywood boards are cut to size.
2. The frame of the panels is made from wooden blocks (50 to 50 mm). It is an edging located on the outer (non-working) side of the shield. It is not necessary to connect the planks to each other, but they are firmly attached to the plywood sheet. For fastening, nails, screws or metal pins (for large shields) are used.
3. Pegs are driven into the trench, designed to stop the shields.
4. The finished shields are placed in the trench, their position is leveled. The distance between the parallel shields is fixed by transverse struts, which are subsequently removed before pouring.
5. The individual panels are interconnected to form continuous formwork walls. The joints are sealed as tightly as possible; when gaps appear, they are immediately sealed.
6. U-shaped clamps are installed on top of the shields with a step of about 1 m, which keep the shields from being squeezed out when pouring.
7. It is recommended to cover the inner part with polyethylene in order to seal the formwork and improve the concrete hardening regime. The plywood will remain clean and can be reused or reused.

NOTE!

After purchasing the material, you need to inspect it and apply a layer of drying oil on the entire surface and end areas. This will help ease the dismantling of the formwork and save it for reuse.

How to assemble from expanded polystyrene

In this case, the formwork cannot be dismantled, being first a mold for casting, and then a layer of insulation. Ready-made blocks of extruded polystyrene foam and additional elements to them are used - jumpers, parts for longitudinal connection, etc.

All of them are commercially available and purchased in advance in the required quantity, which greatly facilitates assembly and allows you to obtain a strong and sealed outer cocoon for the concrete tape. The technology was invented a long time ago, but for various reasons was not used, it is starting to gain popularity only at the present time.

However, the results allow the methodology to predict good prospects.

Assembling the formwork is simple. The blocks are interconnected according to the principle of a constructor, fixing is done using jumpers. The assembly process, in addition to creating a mold for pouring, combines insulation and sound insulation, which reduces the overall work time and simplifies the work in general.

The fewer operations, the less the possibility of errors or technology violations.

The main disadvantage of this method is the high cost of expanded polystyrene blocks, which increases the cost of.

This is the main obstacle to technology diffusion.

Installation of removable formwork with insulation

Do-it-yourself installation of this type of formwork is carried out according to our own method:

1. The trench has a width equal to the thickness of the tape plus a double layer of insulation. Extruded polystyrene foam is usually used. Insulator sheets are installed vertically on the edge and fastened with 20 cm long nails directly to the walls of the trench.
2. Before installing the heat insulator from the reverse side, facade dowels are installed over the entire area... Their ends pass through the material and protrude into the trench in order to ensure a high-quality connection of concrete and insulation after pouring.
3. Wooden formwork is installed along the edge of the trench, forming an upward extension of its walls. The heat insulator is attached to it in the same way as to the ground - with nails, only of a shorter length. The technique for creating shields is common, the only difference is the installation not inside the trench, but along its edges.
4. Pouring concrete ensures tight contact of the tape with the insulation, the absence of gaps and the tightness of the insulation layer. After the concrete hardens, the wooden formwork is dismantled, and the heat insulator remains on the concrete surface. Taking into account the specifics of the material, it is necessary to install a protective layer of the plinth plating to exclude mechanical stress on the insulator.

Dismantle wooden boards it is necessary to be careful not to destroy the expanded polystyrene plates.

Installation of permanent formwork

In addition to expanded polystyrene, concrete is used for the manufacture of permanent formwork. Hollow blocks are produced from it, which are assembled like parts of a designer, forming a hollow wall of the desired size.

After that, concrete is poured inside, filling the voids and forming a monolithic solid wall. This technology appeared earlier than polymer fixed formwork, but, for various reasons, did not receive wide distribution.

The creation of such an external frame allows solving a number of problems with rigidity, tightness of connection with concrete filling and finishing works. and can be produced without waiting for the final hardening of the concrete.

Savings appear building materialsas there is no need for conventional formwork.

The formwork assembly technique is simple and does not raise any questions. Blocks are installed in the prepared trench on the waterproofing layer, a layer of waterproofing is applied to the side surfaces, after which concrete is installed and poured.

The procedure is simple and allows you to significantly speed up the creation of a solid foundation.

How to further strengthen this device?

The weight of the concrete is very high, and the loads on the formwork during pouring can destroy it or create gaps through which the concrete will flow out. For strengthening, additional elements are used that reinforce the walls and take on the load from the weight of the concrete.

Usually, at a distance of about 50 cm from the outer surface, stakes are driven into the ground, to which inclined stops are attached. In addition, horizontal stops are laid from below, tightly inserted between the stakes and the lower edge of the shields.

As a result, a number of additional fastenings are formed that increase the stability of the formwork and protect it from destruction.

When to remove the formwork from the strip foundation?

Dismantling of the formwork is traditionally carried out 10 days after pouring. R various technological options allow earlier or later dismantling within 5-15 days, which is due to the size and thickness of the tape - the larger it is, the longer the holding time in the formwork.

When dismantling at an earlier date, the utmost care must be taken as corners or edges of the tape can be easily beaten off.

Useful video

In this video you will learn how to make the right formwork for a strip foundation:

Conclusion

Formwork is an important and crucial element in creating a strip foundation. It is necessary to treat its assembly with the utmost care and accuracy, without neglecting any stages or elements of technology.

The quality of the casting and the entire foundation to a large extent depends on how reliably and firmly the form is assembled. It is better to spend a little extra time and get the best result, since the fate of the entire building depends on this.

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Any construction of buildings provides for the mandatory installation of floor slabs, which can be either purchased ready-made or made directly at the construction site. Moreover, the latter option is very popular, since it is considered less expensive. To do monolithic slabs independently, it requires the creation of a special structure - floor formwork.

Device

A monolithic floor is one of the main elements of the structure, which increases the operational characteristics of the building and makes it durable. Its installation begins with the assembly of the formwork, which allows the concrete to maintain its shape and immobility until it hardens. Slab formwork is considered to be a complex building structure, which usually consists of such elements.

• Support nodes. it wooden beams, having the form of telescopic racks. In order to evenly and correctly distribute the dynamic load on this element, the distance between them should be accurately calculated. With the help of such supports, formwork is assembled for pouring monolithic slabs no higher than 4 m. Often, additional or starting racks are used in the construction of structures. They are made of metal profiles and are fixed to each other with special fasteners (cup or wedge). Thanks to such supports, formwork up to 18 m high can be built.

The props, which are commonly used for formwork installation in high-rise buildings, consist of three elements: a fork, a vertical support and a tripod. The fork is the upper part and serves, as a rule, to fix the working surface. It is often referred to as the "support fork". This element is produced from four tubes ( square section), which are welded in the corners, and metal plates with a thickness of at least 5 mm. The tripod (skirt) is designed to stabilize the stand and allows it to be held securely horizontally. In addition, the tripod takes on some of the main load when pouring concrete.

According to the standards, in the construction of ordinary residential buildings, it is allowed to use racks to install auxiliary structures following sizes: 170-310 cm, 200-370 cm.If you plan to build private house outside the city, then you can get by with supports of a typical size of 170-310 cm, they are placed in increments of 150 cm.

• Base.It is made from sheet material, which is most often used as sheets of plywood, metal profiles and boards from boards. To increase the strength of the structure, it is recommended to use a material with high moisture resistance.

• Metal or wood beams.These elements are placed perpendicular to each other. For the construction of formwork, you need to choose beams with increased rigidity, since the retention of the mass of concrete and the strength of the formwork itself depend on this.

Slab formwork can be manufactured different types, it all depends on the type of support, the thickness of the concrete pouring and the height of the structure.

Advantages and disadvantages

Slab formwork is considered an indispensable building element. However, they have both advantages and disadvantages. Therefore, before building them, it is important to take into account all the characteristics. The main advantages of formwork include such moments.

• Providing high strength to monolithic slabs. Unlike conventional prefabricated structures, they do not have docking zones and seams.
• The ability to implement non-standard projects, since such formwork allows the manufacture of floors of various shapes.
• Elimination of displacement of floors in the transverse and longitudinal direction. Monolithic slabs acquire additional rigidity.
• Simple installation. It is possible to create formwork on our own without the use of special equipment, which significantly saves construction costs.
• Reusable. The climbing formwork is used to cast hundreds or more of solid slabs. It is financially beneficial.

... As for the shortcomings, there are few of them.

• Compared to the use of ready-made slabs, the time is higher, since it is required to additionally erect and dismantle structures. In addition, the construction process is a little delayed, because you have to wait until concrete pouring gain strength.
• The need for strict adherence to the entire technology of manufacturing and pouring concrete solution. It is difficult to do this, because concrete is poured in huge quantities.

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Slab formwork designed for concreting monolithic slabs is of several types, each of which differs in assembly technology and technical characteristics... Most often, the following type of structures is used in construction.

Stationary (non-removable)

Its main feature is that after the solution solidifies, it cannot be removed. Stationary formwork consists of sheets of thermal insulation and layers of waterproofing material, so they provide the building with additional heat and protection from moisture. At the end of concreting, non-removable structures are transformed into one of the elements of the reinforced concrete structure. These designs have a number of advantages: they simplify the implementation installation worksreducing labor costs and giving the structure decorative view, as they are made of modern materials.

Removable

Unlike the previous type, these structures can be dismantled after complete solidification of the concrete. They are in greater demand than stationary ones, because they are characterized by a low price and easy installation. Many builders rent removable formwork, as this allows you to reduce the cost of assembling the structure and quickly complete the concreting process.

Collapsible

This type of formwork is divided into several classes and differs in the level of complexity. So, for example, when building horizontal planes, a simple (frame) formwork is recommended, but if it is planned to erect buildings of complex shapes, then a volumetric (large-panel) structure is suitable. The assembly of such elements is carried out from moisture-resistant plywood, profiled sheet, polystyrene foam, polystyrene and expanded polystyrene.

In addition, sliding formwork is sometimes used for the construction of small and large modules. It is installed vertically. The type of construction is chosen in construction depending on the complexity of the project.

Technical requirements

Since the slab formwork is responsible for the further strength of monolithic blocks, it must be erected in accordance with the established construction standards, taking into account all technologies and rules. The following requirements apply to this design.

• High safety margin. Each constituent element of the structure must withstand not only the reinforcement cage, but also the weight of liquid and hardened concrete.
• Safety and reliability.During the reinforcement and pouring of the mortar, workers move along the base, so it must be rigid and exclude any vibration. Otherwise, monolithic slabs can get defects, which in the future can lead to emergency situations. Construction tables also help to exclude damage to the integrity of the structure, on which you can also move during construction work.
• Long service life.This primarily concerns the collapsible and removable type of formwork, which are used multiple times in construction. To create a monolithic slab, it is recommended to install formwork made of durable material that will withstand subsequent operation after dismantling.
• Resistance to stress. Since the concrete is poured superficially and with a depression, its mass creates increased dynamic loads on the formwork. In order for the structure to reliably withstand them, it is necessary to correctly select its material of manufacture in advance and prepare a plan for the foundation slab, which complements the formwork drawing and the slinging diagram.
• Have a fast installation. Today, there are many support parts and ready-made sections on the market that allow for quick assembly of structures.
• Disassembly possible.After the mortar has frozen, the formwork, consisting of several elements, can be dismantled for further use. This process should be quick and easy.

DIY installation

The installation of slab formwork is considered a responsible and complex process, so if you plan to assemble it yourself, you must have some experience and comply with all the conditions of technology. Many builders prefer to purchase ready-made monolithic slabs; only jacks and workers are required for their installation. The only thing is that construction equipment is not always available in application and in hard-to-reach places she won't be able to work. Therefore, in such cases, monolithic blocks are best done by hand. To do this, you need to strengthen the formwork, after which the concrete is poured. In more detail, the construction process is as follows.

• At the first stage of the work, accurate calculations should be made. For this, design is carried out and an estimate is made. In the project, it is important to take into account the strength of the formwork so that it does not crack under the mass of concrete mortar. In addition, a slab placement scheme is made, taking into account the features of the configuration of the future building, the concrete grade and the type of reinforcement. So, for example, for the construction of an ordinary residential building, the width of the spans in which will not exceed 7 m, you will need to make a solid floor with a thickness of at least 20 cm.
• At the second stage, all the necessary materials are purchased.These are the foundation for the formwork, supporting and fastening elements.
• The next step is to assemble the formwork itself.Its installation should be started after the walls have been erected, when their height has already been set. For horizontal casting, you can use two types of formwork: ready-made (purchased or rented, it requires only assembly) and fixed. In the first case, it is recommended to choose a structure made of durable plastic or metal, it can be reused after completion of work. The complete set of such formwork usually includes sliding supports that allow you to keep the floor at a certain level. They are assembled very quickly and easily.

In the second case, you will have to assemble the formwork with your own hands from plywood and edged boards. It is recommended to take plywood with increased moisture resistance, and it is best to select edged boards of the same size, this will save you from adjusting them in height in the future. First of all, the foundation is being prepared for monolithic slabs.In the event that gaps appear between the elements during the assembly of the formwork, then it is additionally laid waterproofing material... You can also make a structure from corrugated board. It is much easier to work with it and this material eliminates the formation of gaps.

Great attention should be paid to the choice of plywood. It is advisable to purchase laminated or glued sheets with increased moisture resistance and a thickness of 18 to 21 mm. This material is made from several layers of wood veneer, each of which is laid across the fiber. therefore given view plywood is durable. The installation of plywood sheets must be carried out in such a way that their joints fall on the crossbars, in addition, after assembling the formwork, not a single seam should be visible.

The installation process should begin with the installation of supports that will support the future monolithic block.Both sliding metal elements and homemade ones from logs are well suited as racks (they must have the same thickness and height). The supports must be placed in such a way that a distance of 1 m remains between them, while the distance between the nearest supports and the wall should not exceed 20 cm. Then, beams are attached to the supports, which are responsible for holding the structure. They are additionally equipped with horizontal formwork.