Types of formwork: characteristics, advantages and disadvantages. How to choose and mount formwork. Varieties of formwork. How to make a wooden formwork on their own.

In modern construction, the formation of horizontal, vertical or inclined structures from concrete or reinforced concrete is widely used, whether it is the foundation or a monolithic frame of the building. For this, the concrete solution is poured into a specially prepared framework for making a constant shape - the so-called formwork, from the construction and high-quality installation of which the platform strength and reliability of the result depends.

Content

The formwork is a removable or non-removable auxiliary frame, consisting of shields that support racks and fastening elements intended for forming concrete structures.

Materials for formwork

The bearing elements of the formwork are made of:

wooden array, BRUSIV, plywood - These materials are widely used in private independent construction. The tree has a slight adhesion with concrete solution. Convenient in the installation of metal frames for wooden formwork. For the small-sized construction of thin walls and partitions, formwork from plywood;
metal (aluminum and steel) - It is used for casting reinforced concrete parts on the factories. Metal formwork is stronger and more durable than wooden;
from polystyrene blocks and plates;
combined species - reinforced concrete, fiberglass with metal frame, etc.

Fixing formworks, as well as devices for its movement and lifting are made of steel, in some cases - wooden or aluminum. For the manufacture of workers of flooring and scaffolding, a tree is used for inventory submits - metal. To reduce the adhesion of formwork with concrete, it is periodically treated with special lubricants (aqueous, hydrophobic impregnations, as well as combined).

Varieties of formwork

Depending on the purpose, the formwork is made for overlapping, foundations and walls, as well as elevator mines and columns. The formwork is removable - such systems are intended for multiple use, as well as a non-removable, participating in the formation, which is the internal framework of the construction structure. You can buy formwork for various configuration and volumes, as well as rent. The rental price of the formwork depends on the selected configuration.

Made a variety of formwork of the following purpose:

horizontal - it is used for surfaces, where the load acts from top to bottom, i.e. for overlapping, horizontal surfaces, including tilt;
vertical - intended for the construction of walls, columns, some inclined surfaces;
for shaping of individual rooms;
for the surfaces of the curvilinear form.

Produce various types of non-removable formwork. In general, it is a material that makes up a single formwork wall design. During construction, the panels are installed or blocks into the overall design, after adding thermal insulation materials and fill the concrete, a monolithic wall with certain parameters is formed.

Several types of non-removable formwork are manufactured:

Modular - represent the formwork modules of the correct shape, resembling details of the constructor. The frame frame is collected in a seamless method from facing plates with jumpers, with the addition of insulation materials, reinforcement, filling with concrete. Such technology significantly reduces the construction process (compared with the construction of reinforced concrete slabs).
Panel - in the form of hard panels of formwork and armpanels. The following varieties of panel types of non-removable formwork are manufactured:

of the polystyrene - it is a thermoblocks from foamed material with voids. The panel formwork from expanded polystyrene is mounted with additional reinforcing and fill with concrete;
from a trees - wood chips with cement. The formwork of walls in the form of panels is attached to each other with nails and special screeds, and the snow concrete blocks - the method of seamless masonry. For insulation, add polystyrene liners, then installed reinforcement and poured concrete. The resulting wall must be arranged from the facade and inside;
the glass chamber of the glass beams and metal thermophille - it is mounted on the height of one floor and poured with light concrete. This wall is required to be scented with decorative finish on both sides.

According to the design, the removable formwork happens the following types:

Finely and large-scale formwork shields fully maintain the technological burden, and the additional designs are not required. With the help of large-scale formwork concrete walls of long length, tunnels and overlaps.
The horizontally transferred formwork is used to form a variety of structures extended horizontally, closed-type, large perimeter. The volume-ceased formwork is made by the P-shaped form, which allows for the formation of simultaneously carrying transverse walls and monolithic overlaps. It is a longitudinal-relocated design - for the platform, the design is shifted inside and roll out horizontally. For the formation of walls in the form of a cell of the construction (no floors), a block formwork is used. The volume-ceased formwork is used to form reinforced concrete monolithic walls with overlaps. Its variety - tunnel formwork is used to form two longitudinal and one transverse wall with overlapping over them. To obtain the tunnel, two halftunnels are connected by quick-release locks. Such formwork is used to build buildings with internal monolithic walls and overlaps, as well as facade panels.
Pneumatic - a flexible reinforced shell of certain dimensions on a tissue basis, from a rubanlatex or a polymer film. The pneumatic formwork is installed in the right place and the air is injected, a special lubricant is applied from above to reduce adhesion with concrete, and then concreting is carried out. To accelerate the process in the formwork, heated air or steam can be supplied. Such a formwork is released low, the lifting crane is not required to remove it. The disadvantages include the need for constant injection of air, as well as low rip.
Block-shaped - made in the form of spatial blocks for molding small vertical and horizontal structures. Release rigid in-point, as well as customizable sliding options for such a formwork.

How to make and mount formwork

In modern construction, various types of formwork for the foundation are used. For a ribbon foundation, the above-ground part of which is the base of the building, use a removable formwork - most often made of boards and a wooden bar.

Failure formwork is used in the construction of pile foundations. Asbestos cement pipes or other building materials are asbestos. The cavity of the pipes is poured with concrete to form a fixed reference element of the foundation.

Currently, formwork made of polystyrene foam is widely used to erect belt monolithic foundations - this material gives the base additional insulation properties.

Production of formwork independently

For rustic construction, it is easiest to make a formwork with your own hands from the boards. To do this, you will need to purchase wooden boards with a width of 10 cm, 4 cm thick, as well as bruks of 40x40 mm.

It is necessary to prepare the construction site around the dug trench - to carefully dissolve it and clean it from the construction trash.

Before the construction stage determine, with the help of which methods will be concreted structures. Based on these data, the drawings of the formwork, supporting forests and racks, fasteners.

Stages of work:

From the boards of 3 meters long, shields are knocked down - with segments of bars placed at a meter distance from each other, and nails or self-tapping screws. At the same time, the length of the bars should be larger than the width of the shield. It is necessary that the facial surface of the formwork (in contact subsequently with concrete) was smooth. In addition, hats of nails or self-tapping screws need to be placed on the front side of the shields. The manufactured shields are placed around the perimeter of the prepared trench (drive into the ground).
In places of connection, boards for formwork are installed as supports. They need to be fastened with knives into the ground.
When filling the foundation, the concrete has a significant load on the installed formwork, so wooden clamps are made to give the design of additional stiffness (at least 50% of the shield height). The clamps are fixed in the middle of the segments between the pink.
With the help of a construction level and a plumb, it is necessary to level the horizontal and vertical shields.
The inner side of the two opposite shields is fixed with the help of wooden bars - strut. From above on one straight line with pins, the shields are attached by retainers.
It is necessary to trace so that there are no cracks in the formwork design, through which the solution may occur. This uses waterproofing compositions and materials. For the waterproofing of the foundation, the rolled backrueroid is used, as well as polystyrene plates placed in the underground part of the foundation between the soil and the structure.