TTK. Installation and dismantling of the formwork of a monolithic floor slab. Technological map Technological map for the installation and dismantling of wall and floor formwork

CENTRAL RESEARCH AND DESIGN-EXPERIMENTAL INSTITUTE OF ORGANIZATION, MECHANIZATION AND TECHNICAL ASSISTANCE TO CONSTRUCTION

AOZT TsNIIOMTP

ROUTING
ON THE DEVICE OF POLAR MONOLITHIC FOUNDATIONS USING SMALL-SHIELD FORMWORK

Moscow

The technological map considers the device of columnar monolithic foundations for reinforced concrete columns using metal formwork.

The organization and technology are given construction processes, basic safety precautions are indicated. Design schemes for the organization and technology of work are presented.

The technological map was developed by AOZT TsNIIOMTP (B.V. Zhadanovsky head department, Ph.D. tech. Sciences, O.V. Baranov, L.V. Zhabina with the participation of sector of computer and information technologies Yagudaeva L.M.).

1 AREA OF USE

1.1. The technological map was developed for the installation of columnar monolithic foundations for the frame of civil and industrial buildings using small-panel formwork.

1.2. The technological map provides for the installation of monolithic foundations using small-panel formwork developed by CJSC TsNIIOMTP (project 794V-2.00.000).

1.3. The basement of the 1-412 series with a volume of 14.7 m 3 was taken as a standard in the development of the map.

1.4. The technological map considers the options for supplying concrete mix in construction:

truck crane in bunkers;

concrete pump SB-170-1.

1.5. Concrete mixture transportation is provided by the SB-159B-2 concrete mixer truck.

1.6. The work is carried out during the summer period in two shifts.

2. ORGANIZATION AND TECHNOLOGY OF WORK PERFORMANCE

2.1. Prior to foundation installation, the following work must be completed:

withdrawal was organized surface water from the site;

access roads and roads are arranged;

the ways of movement of mechanisms, places of storage, enlargement of reinforcing meshes and formwork are indicated, mounting equipment and fixtures are prepared;

reinforcing meshes, frames and formwork kits were delivered in the required quantity;

the necessary preparation for the foundations has been completed;

geodetic breakdown of the axes and marking of the position of the foundations in accordance with the project;

on the surface of the concrete preparation, paint marks are applied, fixing the position of the working plane of the formwork panels.

2.2. The prepared base for the foundations must be accepted by the act by the commission with the participation of the customer, the contractor and the representative of the design organization. The act must reflect the conformity of the location, marks of the bottom of the pit, the actual bedding and natural properties soils according to the project, as well as the possibility of laying foundations at the design level, the absence of violations of the natural properties of the foundation soils or the quality of their compaction in accordance with design decisions.

2.3. Acts for hidden work must be drawn up for the preparation device for foundations.

2.4. Before installing formwork and reinforcement iron concrete foundations the foreman (foreman, foreman) must check the correctness of the device concrete preparation and marking the position of the axes and marks of the base of the foundations.

Formwork

2.5. Formwork on construction site must come complete, suitable for installation and operation, without modifications and corrections.

2.6. Received on the construction site formwork elements are placed in the area of ​​action of the erection crane. All formwork elements must be stored in a position corresponding to the transport, sorted by brands and sizes. It is necessary to store the formwork elements under a canopy in conditions that exclude their damage. Shields are stacked in stacks with a height of no more than 1 - 1.2 m on wooden spacers; fights on 5 - 10 tiers overall height no more than 1 m with the installation of wooden spacers between them; the remaining elements, depending on the dimensions and weight, are placed in boxes.

2.7. Small-panel formwork consists of the following components:

line shields are made of bent profile(channel), the deck in shields is made of laminated plywood 12 mm thick;

load-bearing elements - contractions are designed to absorb the loads acting on the formwork, as well as to combine individual panels into panels or blocks. They are made of a bent profile (channel);

corner shields - serve to combine flat shields into closed circuits;

mounting angle - serves to connect boards and panels into closed formwork contours;

tension hook - used for attaching fights to shields;

bracket - serves as the basis for the working flooring.

2.8. Mounting and dismantling of the formwork is carried out using a truck crane KS-35715 or KS-45719, KS-4572A.

2.9. Prior to the installation of the formwork, the panels are assembled into panels in the following sequence:

at the storage site, a box is assembled from contractions;

shields are hung on fights;

on the edge of the panel shields, risks are applied with paint, indicating the position of the axes.

2.10. Foundation formwork is produced in the following order:

install and fix the enlarged formwork panels of the lower step of the shoe;

install the assembled box strictly along the axes and fix the formwork of the lower step with metal pins to the base;

put on the edges of the enlarged panels of the box risks, fixing the position of the box of the second stage of the foundation;

stepping back from the risks to a distance equal to the thickness of the shields, a pre-assembled box of the second stage is installed;

finally install the box of the second stage;

in the same sequence install the box of the third stage;

put on the edges of the enlarged panels of the upper box risks, fixing the position of the column box;

install the column box;

install and fix the formwork of the liners.

Mounted formwork is accepted by the master or foreman according to the act.

2.11. The condition of the formwork must be continuously monitored during the concreting process. In case of unexpected deformations individual elements formwork or unacceptable opening of cracks, additional fasteners should be installed and deformed places should be corrected.

2.12. The formwork may be dismantled only after the concrete has reached the strength required in accordance with SNiP 3.03.01-87 and with the permission of the works foreman.

2.13. In the process of tearing off the formwork, the surface concrete structure should not be damaged. Dismantling of the formwork is carried out in the reverse order of installation.

2.14. After removing the formwork, you must:

make a visual inspection of the formwork;

clean all formwork elements from adhering concrete;

lubricate the decks, check and lubricate the screw connections.

2.15. Schemes of production of formwork works are given in fig. fifteen.

Reinforcing works

2.16. Reinforcing grids of under-columns are delivered to the construction site and unloaded at the pre-assembly site, shoe grids - at the storage site.

2.17. The assembly of the reinforcement cages of the under-column is carried out at the assembly stand with the help of a conductor, by tacking the reinforcing meshes together by electric arc welding or viscous.

2.18. Armoframes and grids of shoes weighing more than 50 kg are installed by a truck crane in the following order:

the reinforcing meshes of the shoe are laid on the clamps, providing protective layer by project.

2.19. Reinforcing work is performed in the following order:

install the reinforcing mesh of the shoe on the clamps, providing a protective layer of concrete according to the project;

after the device of the formwork of the shoe, reinforcing pillars are installed with its fastening to the lower grid with a knitting wire.

2.20. Reinforcing work must be carried out in accordance with SNiP 3.03.01-81 "Bearing and enclosing structures".

2.21. Acceptance of the mounted reinforcement is carried out before the installation of the formwork and is issued by an inspection certificate hidden works. The act of acceptance of the mounted reinforcement structures must indicate the numbers of working drawings, deviations from the drawings, and an assessment of the quality of the mounted reinforcement.

After the formwork is installed, permission is given for concreting.

2.22. Schemes for the production of reinforcing work are given in fig. 6 and 7.

Concrete works

2.23. Prior to the commencement of concrete placement, the following work must be completed:

correctness checked installed fittings and formwork;

eliminated all formwork defects;

F-1 foundation for reinforced concrete columns

Rice. one

Layout plan for formwork boards

Pos. see fig. 3.

Rice. 2

Specification of formwork elements

1. The layout of the formwork panels, see fig. 2.

2. Bracket pos. 20 is conventionally not shown.

Rice. 3

Pos. see fig. 3.

Rice. 4

Scheme of formwork production

1 - automobile crane KS-35715; 2 - storage area; 3 - formwork boards; 4 - contractions; 5 - mounting corners; 6 - enlarged formwork panels; 7 - reinforcing cage; 8 - sling; 9 - concrete preparation

Rice. 5

F-1 foundation reinforcement scheme

Grid layout soles

Reinforcing mesh specification

Rice. 6

Scheme of the production of reinforcing work

1 - automobile crane KS-35715; 2 - storage area; 3 - foundation formwork; 4 - laid reinforcing meshes; 5 - installed reinforcing cage; 6 - sling; 7 - inventory shield(manufactured locally) 8 - concrete cover fixer

Rice. 7

the presence of retainers providing the required thickness of the concrete protective layer was checked;

all structures and their elements are accepted according to the act, access to which, in order to verify the correct installation after concreting, is impossible;

the formwork and fittings are cleaned of debris, dirt and rust;

the operation of all mechanisms, the serviceability of equipment and tools were checked.

2.24. Delivery of the concrete mixture to the object is provided by SB-92V-2 or SB-159B-2 concrete mixer trucks.

2.25. The supply of concrete mixture to the place of laying is considered in two options:

a truck crane in swivel bins with a capacity of 1.6 m 3 of mixture designed by AOZT TsNIIOMTP;

using a concrete pump.

2.26. Foundation concreting works include:

receiving and supplying concrete mix;

laying and compaction of concrete mix;

curing.

2.27. Concreting of foundations is carried out in two stages:

at the first stage, the foundation shoe and the sub-column are concreted to the mark of the bottom of the liner;

at the second stage, the upper part of the sub-column is concreted after the insert is installed.

2.28. To load the concrete mixture, the rotary hoppers do not require transfer racks, but are delivered to the place of loading with the concrete mixture by a truck crane, which sets the hoppers in a horizontal position.

The concrete mixer truck drives up to the bunker in reverse and unloads. Then the truck crane lifts the bucket and delivers it in a vertical position to the place of unloading. In the area of ​​operation of a truck crane, several bunkers are usually placed close to each other with the expectation that their total capacity is equal to the capacity of a concrete mixer truck. In this case, all the prepared bucket bunkers are loaded with concrete at the same time, and then the crane alternately delivers them to the unloading point.

2.29. When concreting monolithic foundations with a truck-mounted concrete pump, the radius of action of the distribution boom makes it possible to place the concrete mix in several foundations. Normal operation of truck-mounted concrete pumps is ensured if a concrete mixture with a mobility of 4 - 22 cm is pumped through the concrete pipeline, which contributes to the transportation of concrete to maximum distances without delamination and the formation of traffic jams.

2.30. Schemes of production of concrete works are given in fig. 8 and 9.

2.31. The concrete mixture is laid in horizontal layers with a thickness of 0.3 - 0.5 m.

Each layer of concrete is carefully compacted with internal vibrators. When compacting the concrete mixture, the end of the working part of the vibrator should be immersed in the previously laid concrete layer by 5 - 10 cm. The vibrator relocation step should not exceed 1.5 of its radius of action. In the corners and at the walls of the formwork, the concrete mixture is additionally compacted with vibrators or by bayoneting with manual screws. Touching the vibrator during operation to the valve is not allowed. Vibration at one position ends when the sedimentation stops and the appearance of cement laitance on the concrete surface. The vibrator should be removed slowly during repositioning, without turning it off, so that the void under the tip is evenly filled with concrete mix.

The break between the stages of concreting (or laying layers of concrete mix) should be at least 40 minutes, but not more than 2 hours.

2.32. After laying the concrete mixture in the formwork, it is necessary to create favorable temperature and humidity conditions for concrete hardening. The horizontal surfaces of the concreted foundation are covered with wet burlap, tarpaulin, sawdust, sheet, roll materials for a period depending on climatic conditions, in accordance with the instructions of the construction laboratory.

2.33. Work on the installation of monolithic concrete foundations is carried out by the following links:

unloading and sorting of reinforcing meshes and formwork elements, loading and unloading of reinforcement cages assembled at the stand, installation of reinforcement cages of under-columns, installation and dismantling of liners - link No. 1:

machinist 5th grade - 1 person,

fitter (rigger) 4 rated - 1 person,

2 bits - 2 people.

formwork works - installation of foundation formwork elements, formwork dismantling with surface cleaning, shield lubrication with emulsion - link No. 2:

construction locksmiths 4 times. - 2 people

3 bits - 1 person,

2 bits - 1 person;

Scheme of the production of concrete work when supplying a concrete mixture by a crane in bunkers

1 - automobile crane KS-35715; 2 - truck mixer SB-92V-2; 3 - swivel bunker BPV-1.6; 4 - sling; 5 - bracket; 6 - fencing; 7 - formwork boards; 8 - concreted foundation; 9 - storage area

Rice. eight

Scheme of the production of concrete work when supplying a concrete mixture with a concrete pump

1 - concrete pump SB-170-1; 2 - truck mixer SB-92V-2; 3 - formwork boards; 4 - concrete foundation

Rice. nine

reinforcing works - installation of reinforcing meshes of shoes, pre-assembly of reinforcing meshes of under-columns on the conductor, welding works - link No. 3:

fitters 3rd category - 1 person,

2 bits - 2 people

electric welder 3rd category - 1 person;

concrete works(when concrete mixture is supplied by a crane) - concrete mixture intake from a concrete mixer truck, concrete mixture supply by a crane, concrete mixture laying with compaction by vibrators, concrete care - link No. 4:

concrete workers 4 size - 1 person,

3 bits - 1 person,

2 bits - 2 people;

concrete work (when concrete mix is ​​delivered by truck-mounted concrete pump) - laying of concrete mix by truck-mounted concrete pump with compaction by vibrators, cleaning of concrete conduit, concrete maintenance - link No. 5:

machinist 5th grade - 1 person;

operator 5 bit. - 1 person,

concrete workers 3rd category - 1 person,

2 bits - 1 person.

2.34. Production of concrete works at negative air temperatures.

When performing concrete work in winter, one should be guided by the rules of SNiP 3.03.01-87 "Bearing and enclosing structures" and SNiP III-4-80 * "Safety in construction".

Winter concreting conditions are considered when the average daily outdoor temperature is not higher than 5 °C or the minimum temperature during the day is below 0 °C.

In winter conditions, the choice of additives and the calculation of their amount is carried out in the same way as in summer.

Construction of monolithic reinforced concrete structures can be carried out, as a rule, using several methods of winter concreting. The choice of method should be made based on the requirements minimum values labor intensity and energy intensity, cost and duration of work, as well as taking into account local conditions (outdoor temperature, scope of work, availability of special equipment, electrical capacities etc.).

Promising are combined methods winter concreting, which are a combination of two or more traditional ways, for example, a thermos + the use of concrete with antifreeze additives, electrical heating or heating in the heating formwork of concrete containing antifreeze additives, electrical treatment of concrete in greenhouses, etc.

Thermos way

The essence of the method consists in heating the concrete by heating the aggregates and water and using the heat released during the hardening of the cement to acquire the specified strength by the concrete during its slow cooling in the heat-insulated formwork.

Application of concrete with antifreeze additives

The essence of the method lies in the introduction into the concrete mixture during its preparation of additives that lower the freezing point of water, ensuring the reaction of cement hydration and concrete hardening at temperatures below 0 °C.

Additives are introduced into the concrete mixture in the form of aqueous solutions of a working concentration, which are obtained by mixing concentrated solutions of additives with mixing water and fed into the concrete mixer through a water dispenser.

Preliminary electrical heating of the concrete mix

The essence of the method lies in the rapid heating of the concrete mixture outside the formwork by passing through it electric current, laying the mixture in the insulated formwork, while the concrete reaches the desired strength in the process of slow cooling.

Preliminary electrical heating of the concrete mixture is carried out in the bodies of dump trucks using the equipment of the post for heating the mixture.

Upon delivery of the concrete mix by truck mixers, the mixture is preheated at the heating post, followed by loading the truck mixer with the heated mixture.

In order to avoid excessive thickening of the combustible concrete mixture, the duration of its heating should not exceed 15 minutes, and the duration of transportation and laying - 20 minutes.

An exoteric method can be used to preheat the concrete mixture. When the mixture is mixed with aluminum powder, an exothermic (with heat release) reaction occurs.

Electrical heating of concrete

The essence of electric heating of concrete consists in passing through it, as through an ohmic resistance, an alternating current, as a result of which heat is released in the concrete.

Steel electrodes are used to apply voltage to concrete.

To power electrical heating and other methods of electrical heat treatment, it is generally allowed to use step-down transformers.

Heating of concrete in thermoactive formwork

The heating method is advisable when using inventory formwork with a steel or plywood deck when concreting walls, ceilings, etc.

It is especially effective in the construction of structures and structures, the concreting of which must be carried out without interruption, as well as structures saturated with reinforcement. The method of heating is economically and technologically expedient not only when using collapsible-adjustable formwork, but also block, volumetric-adjustable, rolling and sliding formwork.

The use of thermoactive formwork does not cause additional requirements for the composition of the concrete mixture and does not limit the use of plasticizing additives. Heating of concrete in a heating formwork can be combined with electric heating of the concrete mix, using antifreeze chemical additives or hardening accelerators.

Heating of concrete structures is carried out after the formwork for concreting. Those parts of the structure that are not covered with thermoactive formwork are insulated with flexible coatings (blankets) made of fiberglass and glass wool.

The technology of concreting in thermoactive formwork practically does not differ from the technology of work in the summer. To prevent heat loss from horizontal surfaces during breaks in the laying of the concrete mix and the outdoor temperature is below minus 20 ° C, the concreted structure is covered with a tarpaulin or film material.

Heating of concrete using heating wires

The essence of the method of heating concrete with the use of heating wires is the heating of concrete with the help of wires in the concrete, which are heated when an electric current is passed. The wires are fixed on the reinforcing bars of the meshes and frames before laying the concrete mixture.

Heating concrete with hot air

The use of hot air to heat concrete leads to big losses warmth. Therefore, this method is advisable to use at a low negative outdoor temperature and sufficiently reliable and tight thermal insulation. Hot air is obtained in electric heaters or fire heaters operating on liquid fuel.

2.35. The list of machines and equipment is given in table 1.

2.36. Scroll technological equipment, tools, inventory and fixtures are given in table 2.

List of machines and equipment

Table 1

List of technological equipment, tools, inventory and fixtures

table 2

3. REQUIREMENTS FOR QUALITY AND ACCEPTANCE OF WORKS

3.1. Requirements for the quality of supplied materials and products, operational control the quality and technological processes to be controlled are shown in table 3.

Table 3

4. CALCULATION OF LABOR AND MACHINE TIME

Table 4

5. WORK SCHEDULE

Table 5

6. NEED FOR MATERIALS, PRODUCTS AND STRUCTURES

6.1. The need for materials, products and structures for the foundation is given in table 6.

Table 6

7. SAFETY AND LABOR PROTECTION. ENVIRONMENTAL AND FIRE SAFETY

7.1. When constructing monolithic foundations, it is necessary to comply with the requirements of SNiP III-4-80 * "Safety in construction", "Fire safety rules for construction and installation works", "Rules for the design and safe operation of cranes".

7.2. The safety of the production of works must be ensured by: the choice of rational appropriate technological equipment;

preparation and organization of workplaces for the production of works;

the use of protective equipment for workers;

conducting a medical examination of persons admitted to work;

timely training and testing of knowledge of working personnel and engineers on safety in the production of construction and installation works.

Particular attention should be paid to the following:

methods of slinging structural elements should ensure their supply to the installation site in a position close to the design one;

elements of mounted structures during movement must be kept from swinging and rotating by flexible braces;

prevent people from being under the mounted structural elements until they are installed in the design position and secured;

when moving cargo by crane, the distance between the external dimensions of the carried cargo and the protruding parts of structures and obstacles along the course of movement must be horizontally at least 1 m, vertically at least 0.5 m; the erection and dismantling of the formwork can be started with the permission of the technical construction manager and must be carried out under the direct supervision of a specially appointed person of the technical staff;

moving a loaded or empty bunker is only allowed when the shutter is closed;

it is not allowed to touch the reinforcement with a vibrator and the worker to be in the zone of a possible fall of the bunker;

only persons who have a certificate for the right to work on this type machines.

7.4. When working at a height of more than 1.5 m, all workers are required to use safety belts with carabiners.

7.5. Dismantling of the formwork is allowed after the concrete has gained stripping strength and with the permission of the work supervisor.

7.6. Formwork is separated from concrete using jacks. The concrete surface must not be damaged during the tearing process.

7.7. Workplaces of electric welders must be fenced with special portable fences. Before starting welding, it is necessary to check the integrity of the insulation of the welding wires and electrode holders, as well as the tightness of the connection of all contacts. During breaks in operation, electric welding installations must be disconnected from the mains.

7.8. Loading and unloading operations, storage and installation of reinforcing cages must be carried out by inventory load gripping devices and in compliance with measures that exclude the possibility of falling, sliding and loss of stability of goods.

7.9. Cleaning the tray of the concrete mixer truck and the loading opening from the remnants of the concrete mixture is carried out only when the drum is stationary.

7.10. It is forbidden: operation of a concrete pump without outriggers; start the operation of the truck-mounted concrete pump without first pouring water into the flushing tank of the concrete transport cylinders, and into the concrete pipeline - "starting lubricant".

8. TECHNICAL AND ECONOMIC INDICATORS

Table 7

Calculation 1

Norms of time for unloading the concrete mixer truck SB-92V-2 in the tank.

The unloading time of the concrete mixer truck according to the technical characteristics of the concrete mixer truck is 8 minutes (0133 hours).

The useful capacity of the drum is 4 m 3 .

N. vr. for unloading 100 m 3 of concrete mix will be:

(100´0.133)/4´1 = 3.32 machine hours

Calculation 2

Norms of time for the supply of concrete mix to the structure by the SB-170-1 concrete pump.

The operational performance of a concrete pump truck is determined by the formula

P e \u003d P t ´ K 1 ´ K 2,

where P t - technical performance of the concrete pump;

K 1 - coefficient of transition from technical to operational performance, K 1 \u003d 0.4;

K2 - the coefficient of performance reduction of the concrete pump, taking into account the non-constant mode of supply, K 2 = 0.65.

P e \u003d 60 ´ 0.4 ´ 0.65 \u003d 15.6 m 3 / h.

Serves a link of two people: the driver of a concrete pumping plant 4 razr. - 1 person, concrete worker 2 class. - 1 person

Norm of time per 100 m 3 of concrete mix for workers:

(100´1)/15.6 = 6.4 man-hours;

for the driver 100/15.6´1 = 6.4 machine-hours

TYPICAL TECHNOLOGICAL CARD

ROUTING
FOR INSTALLATION AND DISASSEMBLY OF THE FORMWORK OF A MONOLITHIC FLOOR PLATE

1 area of ​​use

1 area of ​​use

1.1. The technological map was developed to organize the work of workers involved in the installation and dismantling of the formwork of monolithic reinforced concrete floor slabs.

1.2. The technological map includes the following works:

- installation of formwork;

- demolition of formwork.

1.3. The scope of works considered by the technological map includes:

- slinging and supply of formwork elements (frame supports, racks, tripods, uniforks, wooden beams, plywood) to the mounting horizon;

- device formwork under the beam;

- arrangement of formwork for a balcony slab;

- device formwork under the "tooth";

- arrangement of formwork for overlapping;

- arrangement of formwork for the end face of the floor slab;

- arrangement of temporary fences;

- device of opening formers;

- dismantling of the formwork;

- cleaning, lubrication, storage and transportation of formwork elements.

1.4. Formwork must meet the following requirements:

- strength, immutability, correctness of shape and size;

- reliable perception of vertical and horizontal loads;

- surface density (lack of cracks), exclusion of cement laitance seepage through it;

- the ability to provide the required quality of the concrete surface;

- the possibility of multiple use;

- manufacturability - ease of use, the possibility quick installation and disassembly.

2. Technology and organization of work

2.1. Requirements for prior work

2.1.1. The following work must be completed prior to the installation of the formwork:

- prepared the basis for the installation of formwork;

- the structures of columns and walls were completed, acts of their acceptance were drawn up based on the executive geodetic survey;

- slab formwork elements were delivered and stored in the installation area of ​​the tower crane;

- checked the presence, marking of formwork elements;

- prepared and tested mechanisms, inventory, fixtures, tools;

- lighting of workplaces and the construction site was arranged;

- all measures for the fencing of openings, stairwells, the perimeter of the reinforced concrete slab were completed in accordance with SNiP 12-03-2001 "Labor safety in construction, part 1";

- the height mark was transferred to the floor.

2.2. Work production technology

Formwork installation

2.2.1. The floor formwork device begins with the supply of frame supports, telescopic racks, tripods, uniforks, wooden beams, plywood sheets to the mounting horizon, to the workplace.

2.2.2. Formwork with a lower elevation is executed first. We begin the work with the formwork for the beams.

2.2.3. In connection with the chosen formwork method, a double deck device, formwork is simultaneously arranged for a beam, a balcony slab, a "tooth".

2.2.4. Formwork installation begins with the installation of ID15 frame supports at a distance of at least 50 mm from the edge of the slab in accordance with the arrangement scheme, l.2 and l.3 of the graphic part.

Pre-set the height of the frame support (distance from the floor to the bottom of the main beam) according to the template by adjusting the screw heads and screw feet.

2.2.5. Install the main beams (wooden beam 2.9 m) on the screw heads (crown).

In accordance with sections 1-1, 2-2, 3-3, 4-4 (l.5, 6 of the graphic part) and the layout of the beams (l.4 of the graphic part).

2.2.6. On the main beams, install secondary beams (wooden beams 4.2 m) with a pitch of 400 mm.

In the axes G-D / 1, E-Zh / 7, where the "tooth" passes, if it is impossible to use a beam of 4.2 m (the distance between the walls in cleanliness in these places is 2900 mm and 2660 mm), install two paired beams 2 .5 m

2.2.7. Lay sheets of laminated plywood, 18 mm thick, on the installed secondary beams. Thus, the lower deck is formed (mark +6.040). Nail plywood to wooden beams. See sheet 4 for the layout of plywood, as well as sheets 5 and 6 of the graphic part.

2.2.8. Level the lower deck.

2.2.9. With the help of geodetic instruments, bring to the lower deck the lines of the faces of the concreted beam for the installation of a vertical deck.

2.2.10. The vertical deck of the beam is formed from laminated plywood strips, 300 mm wide. For dimensions and layout, see sheet 3 of the graphic part.

Connect the plywood strips together with a 50x50 beam. The beam is also used to be able to nail to the lower deck and to the upper, see node A sheet 5 of the graphic part.

For the stability of the vertical deck, arrange a brace from a 50x50 beam.

2.2.11. Install wooden beams 2.5 m on the lower deck.

Place a beam 82x82 under these beams (for climbing).

Under the balcony slab, wooden beams are located perpendicular to the concreted beam with a step of 400 mm, under the "tooth" along the concreted beam.

See the scheme for laying out wooden beams on sheets 5 and 6 of the graphic part.

2.2.12. Lay sheets of laminated plywood on the installed wooden beams, in accordance with the layout diagram of sheet 3 of the graphic part.

2.2.13. For the device "tooth" where the wall passes, use a bracket.

The bracket is attached with a tie.

A bar 100x100 is laid on the bracket.

Laminated plywood is attached to the beam.

See section 6-6 and 7-7 of sheet 7 of the graphic part for the deck layout.

For the layout of brackets for tooth formation, see sheet 2 of the graphic part.

2.2.14. Formwork for floor slab.

In accordance with the layout diagram (sheet 2 of the graphic part), measure with a meter and mark with chalk the installation sites of the racks.

Start by installing the end posts under the main beams, at a distance of 4.0 m along the letter axes.

The distance between the uprights along the digital axes corresponds to the pitch of the main beams.

2.2.15. Insert the unifork into the rack. Expand the rack according to the template to the length specified by the height to the main (lower) beam. Install the rack and unfasten the tripod.

2.2.16. Install the main beams (wooden beams 4.2 m) on the installed and unfastened racks using a mounting fork. The step of the main beams is 1.5 m.

2.2.17. On the main beams, using a mounting fork, install secondary beams (wooden beams 3.3 m) without fasteners. The pitch of the secondary beams is 0.40 m.

2.2.18. Lay sheets of laminated plywood on the secondary beams, close to each other so that the gaps between them are no more than 2 mm. The first sheets of plywood are fed from the concrete floor, after laying at least 12 sheets, the plywood is fed to the deck.

Sheets and strips of plywood extreme along the perimeter are fastened with nails to secondary beams to prevent tipping.

See sheet 3 of the graphic part for the layout of plywood.

2.2.19. Plywood sheets suitable for the formwork under the beam should be laid last, after the vertical beam deck has been installed.

2.2.20. For the convenience of mounting the formwork (as well as dismantling), cut a standard plywood sheet into pieces 2440x610 mm.

2.2.21. In several places, it is recommended to use ordinary plywood impregnated with a lubricating emulsion.

2.2.22. Places cut laminated plywood become susceptible to moisture and are subject to moisture-resistant treatment (molten paraffin, treatment with two layers of primer).

2.2.23. The deck surface must be leveled.

2.2.24. After installing the floor slab deck, balcony slab, "tooth", arrange a side, with a height equal to the thickness of the overlap.

The formwork of the floor end is performed as follows.

The line of the end of the slab is made, strips of plywood are attached to the deck along the line, with a width equal to the height of the ceiling. To avoid capsizing the end, arrange a brace from a 50x50 beam.

2.2.25. With the help of universal fences that are attached to wooden beams, arrange a temporary fence. Install fence posts, with a step of no more than 1200 mm, insert fencing boards into the brackets of the racks.

2.2.26. Promoter device. The openings are made from laminated plywood. The size of the opening formers along the outer edges corresponds to the dimensions of the opening in the floor slab. The opening formers are installed in the design position and nailed to the floor slab deck.

One of the first stages in the construction of structures for various purposes is the installation of formwork. Often this process goes unnoticed. But already at the stage of preparation for pouring, it becomes clear that not everything is as simple as it was thought at first. Assemble the frame will help installation instructions formwork.

Formwork types

There are three types of construction:

• Removable, which is dismantled after the solution has completely dried. Such a formwork is assembled from separate parts. The result is collapsible design which is dismantled and can be reused. Among the advantages of this type of formwork are ease of installation, the ability to reuse, which significantly reduces financial expenses for construction.

• Fixed, respectively, one that is not dismantled. Installation of formwork of this type is carried out mainly from expanded polystyrene or polystyrene. It remains part of the structure under construction. And at the same time it acts as a heater.

• "Floating" formwork is typical for the construction monolithic foundation which is immersed in the ground. It is a shield assembled from boards, which is slightly higher in height than the planned concrete structure. The shield is lowered into the pit and attached to its walls. Cardboard or roofing material is rolled on top of it.

There are also several types depending on the purpose:

• Wall formwork. Its installation is carried out for the construction vertical structures and walls.

• Horizontal, which is used for mounting the foundation and floors.

• Curved, which allows you to fill in details of unusual shapes.

Mounting and dismantling of formwork of each type has its own characteristics. You need to know them to get the job done right.

Advantages of fixed formwork

Installation of fixed formwork involves the purchase of a ready-made set for the work. It remains only to assemble the structure and install it. This implies a number of advantages that formwork of this type has:

• short terms of performance of works;

• ease of installation;

• low weight of the structure;

• resistance to the appearance of fungus and mold;

• fire safety;

• small cost.

Also fixed formwork is at the same time a layer of insulation and is a block of foam, which are easily connected to each other. The inner wall is thinner than the outer one. This achieves high level thermal insulation.

Construction of fixed formwork

Finished shields are attached to the corner bars with self-tapping screws or nails. Fastening must be secure. When the concrete expands, the pressure on the shield will increase, which can lead to cracking of the boards. The main thing is that the bar itself remains with outer side. Parallel assembled structure going to another row at a distance of the future wall. As a result, you should get a frame around the entire perimeter.

A layer of crushed stone or sand is poured into the finished formwork box. This will protect the solution from moisture loss, which will go into the ground. Formwork installation technology provides protection against the flow of mortar through the existing holes. To do this, the shields are covered with a film or roofing felt, which are fastened with screws or staples using a stapler.

All work must be carried out taking into account the level. It is very important. At each stage, the evenness of the structure in height, length and vertical is checked (especially important). Two rows of shields must run strictly parallel to each other.

The main elements of the formwork

Removable formwork, which is assembled independently, consists of the following elements:

• The deck, which is a flat shield, is the enclosure of the entire form. The structure must be strong enough to withstand the pressure of the solution. Therefore, it is made of plywood or edged boards 4-5 cm thick.

• Scaffolding that is the support of the structure. They hold the walls, preventing the solution from squeezing out the deck. Scaffolding is made from pine bars or boards (2.5-5 cm).

• Fasteners are all the details with which all structural elements are twisted: wire, clamps, ties, hardware, and so on.

The deck is most often assembled from boards 15 cm wide, which are connected in several rows using nails (driven in from the inside, bent from the outside) or self-tapping screws (they are twisted with inside). The distance between the boards should not exceed 3 mm. Shields are fastened together with additional slats.

A simpler deck manufacturing option is to use moisture-resistant plywood 1.8-2.1 cm thick.

Formwork installation

The frame will be installed evenly and level if the site is properly prepared in advance. It is marked with the help of cords stretched between the pegs. Fall asleep and thicken sand cushion. If necessary, a pit is prepared.

Formwork installation takes place in the following sequence:

• The perimeter should be marked with vertical guides ( wooden blocks, metal corners or pipes).

• It is required to place ready-made shields along the guides, maintaining the required distance between them (it is equal to the required thickness of the foundation).

• Firmly fix the deck. Support it from the outside with inclined bars (1 brace for each meter of deck).

• Connect the shields to each other with 5x5 cm bars.

• Cover the inner side of the formwork with a film (roofing material).

Foundations up to 20 cm high do not require serious construction. For them, bars driven into the ground are enough.

Installation of wall formwork

More difficult is the process of erecting wall formwork. At the same time, small-panel and large-panel formwork are distinguished.

The first option is suitable for the construction of small buildings ( country houses, utility buildings) and partitions between rooms. In this case, small-sized plywood shields are used.

The installation of large-panel formwork is typical for the construction of buildings with a large height. For work, use sheets of metal or large sheets of plywood.

For the installation of walls, a foundation is prepared, into which reinforcement is stuck. A two-row formwork frame is assembled around it. When using ordinary plywood, the joints are coated with glue or sealant. Currently, there is a special formwork plywood on the market. Separate sheets it is connected according to the tenon-groove principle, which does not require additional sealing.

Types of floors

The installation of the ceiling formwork depends on the type of ceiling itself. Allocate the following types designs:

• On big bowls. It is used for structures with high height. In this case, vertical racks, jacks, inserts, crossbars and other elements are used to connect individual parts.

• On blade scaffolding, which is used for multi-storey buildings. Scaffolding is installed instead of plywood boards.

• On scaffolding of cup type. This view provides for the installation of the frame. Racks are interconnected by the cup method.

• On telescopic bowls. Suitable in cases where the ceiling height is less than 4.6 m. It is based on tripods that support the entire structure. From above boards from moisture resistant plywood keep within.

Formwork for overlapping

Currently, monolithic overlap is most often used. Using his example, we will analyze the process of mounting the formwork.

For formwork, vertical racks are used, interconnected by crossbars. They are attached at right angles to the bars running in the transverse direction. A plywood shield is laid on these transverse bars, which is the bottom of the formwork.

To perform these works, the following materials are used:

• stand - timber with a cross section of 12-15 cm;

• crossbar and transverse beam - edged board 16-18 cm wide and 5 cm thick;

• braces - a board 3 cm thick;

• flooring - moisture resistant 1.8 cm thick.

Before starting work, it is necessary to carry out accurate calculations. It is important to determine required amount racks, the step of their placement and other indicators.

Slab Formwork Assembly Instructions

The work instruction includes the following steps:

• Longitudinal bars are attached to the upper part of the racks, the second end of which is fixed on the wall.

• The second row is assembled in the same way. To do this, a board 5 cm thick is laid under the supports.

• Cross bars are laid in increments of 60 cm.

• Install support racks (strictly vertically).

• Racks are interconnected by braces.

• Sheets of plywood are laid on the transverse bars, leaving no gaps.

• The ends of the overlap are protected by masonry of blocks or bricks.

• The frame is assembled from reinforcement. At the same time, they leave, if necessary, space for communications.

When all work is completed, concrete can be poured. The formwork is removed after 3 weeks.

Conclusion

Installation of formwork of each type involves the use of certain materials. If boards are used, they must be new. Rotten old boards can not withstand the load and break. Plywood must be moisture resistant or laminated.

All work must be carried out in accordance with the calculations made. This is especially important for the installation of formwork for floors and walls.

Formwork installation is carried out using a tower crane KB 403 with a boom length of 30 m, installed in accordance with the construction plan. Mounting of the formwork should be carried out according to the grips. Each floor is divided into two sections in the plan.

Concreting of columns, walls and floors should be done in the Peri formwork. The formwork kit consists of:

• - WALLS - made of metal panels, lined with waterproof plywood 21 mm thick, withstanding the pressure of freshly laid concrete 60 kN/m 2 ; straightening locks BFD, providing connectivity, evenness and density of formwork panels in one operation; strands DV - 15 with a nut - gasket with a permissible load on the strand of 90 kN; RCC leveling rods with a support, ensuring the stability of the formwork structures and designed for a load of 30 kN; suspended scaffolding consoles TRZH 120, providing safety when the load on the scaffold is 150 kg/m 2 .
• - COLUMNS - TRS metal shields, lined with waterproof plywood 21 mm thick, withstanding the allowable pressure of freshly laid concrete 100 kN / m 2, column tension bolts with an allowable bolt load of 90 kN.
• - FLOORS - from lattice beams GT 24 various lengths with bearing capacity - transverse force in spacers - 14 kN, bending moment - 7 kNm, supports PER 30 with a bearing capacity of 30 kN; boards made of waterproof plywood 21 mm thick.

Formwork is delivered to the construction site in special containers by road and stored under a canopy.

See the formwork installation diagram below, it shows the layout of the work tables and the installation and docking of the PERI carts.

Prior to the installation of the formwork on the clamp, it is necessary to perform:

• - to concrete a reinforced concrete slab with reinforcement outlets for columns, walls, an elevator shaft;
• - put the risks of centering axes on reinforced concrete slabs;
• - to make drawing on boards of a timbering of a concrete separating liquid "Pera - Klin" by means of an airbrush;

installation of design fittings;

delivery of tools, fixtures and equipment to the workplace.

Formwork installation scheme.

The sequence of mounting the formwork on the grip:

WALLS and COLUMNS:

• - install a block of external formwork panels on spacers;
• - install fittings;
• - install a block of internal shields on tie rods and locks with hanging scaffolding and decking consoles.

The removal of the main axes of the building to the slab is carried out from the benchmarks. From the main axes of the measurement paths, all other axes of the building are taken out. Construction control monolithic house vertically to produce floor-by-floor theodolites by the method of inclined design.

When performing geodetic work, it is necessary to be guided by SNiP 3.01.03 - 84 "Geodetic work in construction".

To reduce the adhesion of the deck to concrete surface clean it thoroughly and spray it with Peri-Clean concrete separating liquid. Cleaning should be carried out immediately after the formwork has been removed by spraying with water, then with a rubber-tipped scraper and a bristle brush and spraying with concrete release agent. Application of concrete separating liquid manual spray gun. Application should be carried out at the storage site (in winter - in a warm room). Provide measures to prevent the lubricating film from being washed off by rain.

Formwork slinging is carried out using special hook TRIO, which is included in the formwork kit, and a transport sling with four ropes. Use two TRIO crane hooks ( load bearing capacity one hook - 1.5 t).

See the scheme of slinging of formwork elements below.

Lifting of small and piece elements should be carried out in containers.

Scheme of slinging formwork elements.

The sequence of operations during the installation of wall formwork:

• - the position of the diaphragm is marked in place, using perforators, holes W = 25 mm 90 mm deep are drilled in reinforced concrete slabs for the installation of anchors NKD-S M 20.
• - on the bench, in a horizontal position, a package of shields (3 pcs.) is assembled, connected by BFP locks with RSS1 spacers mounted on them.
• - with the help of crane hooks of the Peri system (2 pcs. per transport unit), the board package is lifted to a vertical position and transported by crane to the installation site.
• - a package of shields is installed according to the risks in the design position on the outer section of the diaphragm and fastened with spacers RSS1 and anchors NKD - S M20 to reinforced concrete slab. Separate panels or packages of panels are attached to the installed formwork, depending on the length of the diaphragm, and fastened together with BFD locks in the amount specified in the project.
• - the entire structure is brought to a vertical position with the help of RSS1 spacers, and then the reinforcement work is started.
• - after completion of the reinforcing work, the inner row of formwork panels is mounted, connected to the previously installed panels using DW - 15 bands and washers, with the installation of PVC-U pipes W = 25 mm long for the thickness of the diaphragm.
• - then end shields Shch-1 are installed, connected to the formwork panels with BFD locks and leveling locks TAR-85, scaffold consoles TRG - 120 are hung and wood flooring 35 - 40 mm thick.

The entire structure is finally brought to a strictly vertical position and is handed over for concrete work.

COLUMNS:

• - Reinforcing works are carried out.
• - on a horizontal stand, a formwork block is assembled from two panels connected by column bolts.
• - with the help of a crane equipped with slings with two TRIO hooks, the unit is brought to a vertical position and installed on a horizontal platform and temporarily fixed to the base with a spacer RSS1.
• - the third shield is mounted.
• - a block of three shields is transported to the installation site with the help of a tower crane with two TRIO hooks and mounted in the design position with RSS1 bracing to the floor slab.
• - the fourth shield is mounted and secured with the spacer RSS1.
• - scaffolding consoles are hung, and a shield scaffolding is carried out.
• - the formwork is brought into a strictly vertical position with the help of RSS1 spacers. The formwork is ready for concreting the elevator shaft.

The marking of the internal elevator shafts on the foundation slab is in progress.

On the stand in a horizontal position, four packages of shields are assembled for the length of the inner wall of the elevator shaft with fastening between them with BFD locks according to the project.

Using the crane hooks of the TRIO system (2 pcs. per transport unit), the package is lifted to a vertical position and transported to the installation site tower crane. The package is installed in the design position with temporary fastening with the RSST spacer to the reinforced concrete slab. Then the rest of the board packages are installed and connected with BFD locks according to the project.

Reinforcing works are being carried out.

After the completion of the reinforcing work, the outer panels of the formwork of the elevator shaft are installed, connected to the previously installed formwork with DW 15 bands with washers and PVC-U pipes Ø 25 mm long for the thickness of the elevator wall, leveling locks TAR - 85 and between themselves BFD locks according to the project.

The RSS1 spacers are installed, the TRG-120 scaffold consoles are hung and the boarding is carried out according to the project.

With the help of RSS1 spacers, the structure is brought to a vertical position and delivered for concrete work.

Concrete work in progress.

Elevator shaft formwork mounting sequence from +0.000 mark

In the upper holes, freed from the cords, are installed supporting elements(rack-stop) for supporting the next tier of formwork according to the project.

A flooring device is being made in the elevator shaft and in the stairwell for the production of installation and reinforcement work.

The inner formwork of the elevator shaft (assembly) is mounted using a tower crane on the installed supporting elements (racks-stops) in the elevator shaft.

Reinforcing work is being carried out on the tier of the installed formwork in the elevator shaft.

External formwork panels are mounted with the installation of DW1 ties, PVC-U pipes Ø 25 mm with fastening with BFD locks, spacers RSS1 with fastening with anchors NKD - S M20, scaffolding consoles TRG - 120 are hung and boarding is carried out on them according to the project.

The entire structure is brought to a strictly vertical position and is handed over for concrete work.

Concrete work in progress.

OVERLAPPING

Installation and dismantling of the formwork of the "multiflex" slab is carried out according to the technological map.

DISMANTLING THE FORMWORK.

The dismantling of the formwork of columns, walls and the elevator shaft should begin when the concrete reaches a strength of 1.5 MPa, the ceiling is 15 MPa.

The order of dismantling the formwork.

• - a block of two internal shields is dismantled
• - the next block of two shields is dismantled

• - the inner row of shields is dismantled
• - end and corner shields
• - outdoor block of shields.

ELEVATOR SHAFT

• - dismantling the internal formwork block
• - dismantled the outer formwork.

OVERLAPPING

• - dismantled intermediate racks
• - lowered by 4 cm main racks
• - dismantled cross beams
• - formwork panels are dismantled
• - formwork panels are dismantled
• - dismantled the main beams
• - Racks are dismantled.

The sequence of operations during the dismantling of the formwork.

• - remove the panel board
• - remove scaffold consoles
• - release the column bolts on the block of two shields
• - sling a block of two shields using TRIO hooks, disconnect the leveling rods from the fastening
• - using a tower crane, lower it to the storage area to prepare for the next concreting.
• - lash the next block of two shields, disconnect the leveling rods and lower with a tower crane to the storage area.

• - remove the panel board
• - remove scaffold consoles
• - sling the inner shield block of three shields with two TRIO hooks
• - remove the BFD locks from the block of shields connecting with the next block of shields, disconnect the rods and locks that equalize the rods
• - using a crane, release the block of three shields and lower it onto the storage area.
• - repeat all operations with the following blocks of shields
• - sling end shield
• - release it from the cords and constipation and lower it onto the storage area with the help of a tower crane
• - tie up the outdoor unit of three shields
• - remove the leveling rods, BFD locks fastening with the next block of shields and lower them to the storage area using a crane
• - repeat these operations with the following blocks of external shields.

ELEVATOR SHAFT

• - remove the tightening rods, constipation.
• - sling indoor unit formwork with four sling hooks and use a crane to remove the block from the elevator shaft in its entirety and place it on the storage site for further preparation.
• - sling the end block with the unbuckling element and use a crane to remove it from the shaft and lower it to the storage area
• - remove the panel board and scaffold consoles from the next outer wall of the elevator
• - sling this block with two TRIO hooks
• - remove the leveling rods and use a tower crane to remove the block from the elevator shaft and lower it to the storage area
• - repeat these operations with the next block of the outer wall of the elevator.

OVERLAPPING

Dismantling of the formwork is carried out according to the technological map.

Safety engineering.

On the grip where they are installation work, it is not allowed to perform other work and find unauthorized persons.

Cleaning of the structural elements to be installed from dirt and ice should be carried out before they are lifted.

It is not allowed for people to stay on structural elements during their lifting and moving.

It is not allowed to find people under the mounted elements until they are installed in the design position and secured.

Unslinging of formwork blocks is carried out from mounting towers H = 2.5m (5.14 D of catalog 2617-961-89), external panels from block decks.

It is not allowed to carry out installation work at height in open places at a wind speed of 15 m/s or more, with icy conditions, thunderstorms, fog, which excludes visibility within the front of work. Work on moving formwork panels with a large sail area should be stopped at a wind speed of 10 m/s.

During the installation of formwork, installers must be on previously installed and securely fastened structures or scaffolding.

When installing panels with a large windage, it is necessary to use braces to keep the panel from swinging.

Every day, before starting work, the foreman (foreman) must check the condition of the assembled panels and formwork blocks, working platforms, hanging platforms and stairs.

Carry out welding and gas-flame work wooden formwork without appropriate security measures is prohibited.

Perform work in accordance with the requirements of SNiP 3.03.01-87 "Bearing and enclosing structures", SNiP 12.03-2001 part 1, SNiP 12.03-2001 part 2 "Labor safety in construction", SNiP 21.01 - 97 "Fire safety of buildings and structures" , SNiP 2.02.02-85* "Fire safety standards".

Technological map for concrete work of a monolithic house in the formwork "PERI"

Concreting of columns, walls and ceilings should be carried out with grips. Each floor is divided in terms of 2 grips. The working seam is indicated in the project. During the installation of reinforcement at the boundary of the grips in the ceiling, install a woven mesh GOST 3826-82, tying it to the reinforcement with a knitting wire. The resumption of concreting in the places of construction of working joints is allowed when the concrete reaches a strength of 1.5 MPa. To clean the working joints from the cement film with an air jet from the compressor. It is allowed to arrange working seams - for columns and walls at the level of the bottom of the floor slab, for overlapping in the middle of the span 3-4 or 4-5 - parallel to the digital axes. In the initial period of hardening of concrete, it is necessary to protect against ingress precipitation or moisture loss.

Prior to the start of concreting, the following work must be performed on each grip:

• - installation and alignment of formwork
• - fittings installation
• - an act of examination of hidden works for the installation of fittings, embedded parts, corrugated power pipes, formwork was drawn up.

When concreting columns, use concrete of class B 20, frost resistance grade F50; internal walls(diaphragm) - concrete class B 20, frost resistance grade F50; elevator shafts - concrete class B20, frost resistance grade F50; floors - concrete class B20, frost resistance grade F50.

The movement of people on concreted structures and the installation of formwork of overlying structures is allowed when the concrete reaches a strength of at least 15 MPa.

Concrete is delivered to the construction site in truck mixers. At the construction site, organize a place for receiving concrete from truck mixers in the form of two bunkers. For uniform distribution of concrete in the formwork of walls and columns, unload concrete into funnels installed in the formwork.

Reinforcement of walls and columns is carried out directly on the grip manually from individual rods and frames, having previously delivered the workpieces to the ceiling with a crane. The fixation of frames in relation to the edges of the wall in order to form a protective layer should be carried out with the help of clamps according to grades, depending on the W of the reinforcement on which it is put on and the thickness of the concrete protective layer. Laying of concrete within the scope of work should be carried out in horizontal layers 500 mm thick. When compacting the concrete mixture, the vibrator's immersion depth should ensure its immersion in the previously laid layer by 5-10 cm. Vibrate until air bubbles appear on the concrete surface, vibrate especially carefully in the corners of the formwork.

Reinforcement of the floor slab should be made from frames and meshes manufactured at the factory (reinforcing yard of the construction site). Grids and frames are delivered to the workplace by a tower crane and mounted in the following sequence:

• - a number of lower grids are installed
• - installation of support frames
• - upper grids are mounted.

The assembly of spatial frames into volumetric ones is carried out using a knitting wire. Fixation of the lower grids in relation to the floor plane in order to form a protective layer is carried out using plastic clamps (TU 6-05-160-77). Simultaneously with the installation of reinforcement, lay horizontal PVC pipes for transmission of electrical communications. Stretch the wire into the tubes before laying. Attach the tubes to the fittings with a knitting wire. At the same time, all embedded parts are installed in the formwork according to the project. Laying of concrete within the designated area of ​​work should be carried out to the depth of the ceiling thickness without breaks, with a consistent direction of laying in one direction. The height of free dropping of concrete from the bunker is not more than 1m. vibrating to produce until the appearance of air bubbles on the surface of the concrete, until the appearance of cement laitance.

Safety engineering.

• 1. The place for receiving concrete should be fenced on three sides, except for the side of the entrance of cars, signs “Caution, a fall is possible” are installed on this side.
• 2. Climbing the scaffolding to carry out the inventory ladders.
• 3. When compacting the concrete mixture, it is not allowed to rest the vibrators on the reinforcement and embedded products, rods and other elements of the formwork fastening.
• 4. Every day, before starting to place concrete into the formwork, it is necessary to check the condition of the container, formwork and scaffolding. Faults found must be corrected immediately.
• 5. When compacting concrete with electric vibrators, it is not allowed to move the vibrator by current-carrying hoses, and during breaks in work and when moving from one place to another, the electric vibrators must be turned off.
• 6. Placement on the formwork of equipment and materials not provided for by the project for the production of works, as well as the stay of unauthorized persons is not allowed.
• 7. Before starting work on the installation of reinforcement, install a fence on each grip on the ceiling along the perimeter.
• 8. Perform work in accordance with the requirement of SNiP 3.03.01-87 "Bearing and enclosing structures", SNiP 12.03-2001 part 1, SNiP 12.03-2001 part 2 "Labor safety in construction", SNiP 21.01 - 97 "Fire safety of buildings and structures”, SNiP 2.02.02-85* “Fire safety standards”.

Individual and industrial construction of multi-storey monolithic buildings, bridges and overpasses is carried out using formwork ceilings. They are easy to install and allow you to build buildings of various shapes and sizes in various climatic zones with an ambient temperature of +45 to -40 degrees C.

Formwork on volumetric racks

Types of slab formwork

From the main specifications object under construction - its withstand load, dimensions, height of ceilings - depends on the use various kinds formwork:

• recommended for ceilings up to 5 meters high. They are the most economical of all formwork types and are erected within a short period of time. The tripod base is quite stable and securely supports the main rack. Moisture-resistant plywood boards are located on beams made of wood or metal profiles.
• Volumetric slab formwork racks are erected at a height of up to 20 meters. Ease of installation is ensured by vertical racks connected by crossbars, flange systems and jacks. According to the method of installation are divided:

1. on wedge scaffolding - with a frame of horizontal and uprights, which can be installed at different angles, depending on the complexity of the work performed on different areas construction. Scaffolding and work ladders provide required level safety of working personnel.
2. with cup scaffolding - allowing you to install up to 4 structural elements on the same level.

The device of volumetric racks

On the jack, the main starting rack is mounted, on which additional racks of different lengths are fixed into flanges. In the same flanges, horizontal crossbars are installed that fasten the formwork sections. Additional racks and crossbars of different lengths allow you to build sectional groups of various sizes. The top of the structure is crowned with a jack with a unifork, on which wooden or metal deck beams are attached.

Starting and additional racks are made of metal, providing the necessary rigidity of the structure. It can be reinforced with additional special flanges installed a meter apart. Ease of installation provides one narrowed end of the rack. The uniform distribution of the load is guaranteed by wedge clamps, which also increase the reliability and strength of the entire structure.

Specifications:

• The maximum height limit, m - 20.
• The minimum height limit, m - 1.5.
• Rack pitch, m - 1.0; 1.25; 1.5; 1.75; 2.0; 2.5; 3.0.
• The maximum limit of the distributed load on the bolt, kg - 1200.
• Permissible turnover - 100 cycles.
• The maximum turnover is 200 cycles.
• Section height, m ​​- 0.5.

Calculation of formwork for construction depends on total area erected building and axle load. For ease of installation, the distance between the racks is from 1 to 3 meters in half-meter increments. plywood sheet is selected taking into account trimming to fit to the size on the sites to be installed.

Advantages of 3D slab formwork props:

• Safety of operation at the expense of rigid and reliable fastening.
• The ability to move individual units without disassembling them using lifting devices.
• Ease of assembly and dismantling with the help of universal fastening elements of the entire system.
• Most effective when working at high altitude.
• Can be used for finishing work.
• Long - up to a maximum of 200 cycles.
• Possibility of developing individual design decisions in construction.

Manufacturers of slab formwork props offer not only standard sizes of all components, but also make structures by order of construction organizations. It is possible to purchase a ready-made set or rent it, which will significantly reduce the cash costs for construction.

Regulatory documentation for slab formwork

Each manufacturer prepares its own internal standards for the production of structural elements. All components of the formwork must comply with the requirements for products of the 2nd hazard class in accordance with GOST R 52085 - 2003, which must be confirmed by a certificate from the regional authority of Rosstandart. Technological process production is strictly regulated by the company's specialists at every stage.

When installing the structure and working at height, safety requirements must be observed. All actions must be carried out in special protective clothing and using personal protective equipment. Employees must be familiar with the basic technical documentation and be licensed to work.

How to make volumetric formwork yourself

It is much more economical to make formwork when building a private house with my own hands. But it is worth considering the following nuances:

• With special attention you should approach the installation of support racks that carry the main load. Reliability provide metal supports, but working with them is a little more difficult than with wooden ones.
• Ensure the rigidity of the base installation. To do this, the installation is carried out on a carefully prepared site - irregularities are compacted and wooden spacers are laid along the axes.
• Longitudinal beams are attached to the racks on metal corners using bolted connections.
• The transverse beams do not require fixing, but are simply laid on the longitudinal ones. This helps to facilitate the dismantling process after all work is completed.
• With the help of braces, the support posts and longitudinal beams are fixed.
• Plywood should be laid tightly to each other, carefully monitoring the joints, which should be located strictly on the floor beam.
• The most optimal distance between the racks is 1.5 meters.
• Alignment of the entire structure is carried out using a level or level and plumb line.
• The installation of each subsequent tier should be carried out after carefully fixing and checking the previous one.

For the manufacture of formwork, you can use existing lumber, but they must not be rotten and carefully dried from wood. conifers. The bars of the racks must have a cross section of at least 12 * 12 cm, and beams 16 * 16 cm.

Formwork dismantling

Dismantling work depends on the timing of the drying of concrete or the completion of the necessary finishing measures. In hot summer weather, the formwork can be removed after 3-4 days. All work is done in reverse order, which was carried out during assembly. After that, the formwork can be reused. To do this, it is necessary to label all elements, sort and clean all contaminants.

Installation and dismantling of volumetric formwork of ceilings is a rather troublesome and complicated matter. Extreme attention and concentration are required during assembly, on which the life and health of workers may depend. But with some knowledge of technology and the required materials, it is possible on your own complete all required work within the scheduled time frame.