MINISTRY OF TRANSPORT CONSTRUCTION OF THE USSR

STATE ALL-UNION ROAD

RESEARCH INSTITUTE

FOR INSTALLING INSERTIONS

AND ANCHOR BOLTS BY GLUING TO CONCRETE

AND PROTECT THEM FROM CORROSION

Approved

Deputy Director of Soyuzdornia

cand. those. Sciences B.S. Maryshev

They allow you to reasonably assign the geometric parameters of attachments of embedded parts and perform high-quality gluing them to the surface of concrete and (or) in holes drilled in it. Bonding of embedded parts to concrete in the form of: steel plates with anchor rods welded to them; concrete with anchor bolts; an anchor rod with a ring, plate or hook for fixing communications or equipment; steel plates attached to concrete with through anchor bolts fixed on a plate. All types of necessary work are described: from design and calculation of embedded parts to control the quality of their bonding.

Foreword

During the operation of bridge structures, it becomes necessary to replace worn-out expansion joints, build up curbs, install parapet or barrier fences instead of curbs, install additional reinforcement, etc. When performing these works, it is required to attach additional embedded parts and anchor bolts to concrete. In these "Methodological recommendations for installing embedded parts and anchor bolts by gluing to concrete and protecting them from corrosion" a technique is provided that allows you to reasonably assign the geometric parameters of the attached parts and perform the listed work. Methodological recommendations were developed by candidates of technical sciences B.P. Belov and I.D. Sakharova. The authors agree to provide practical assistance in the implementation of the recommendations on a contractual basis. Please send comments and suggestions on this work to the address: 143900, Moscow region. Balashikha-6, Soyuzdornia.

1. General Provisions

1.1. "Methodological recommendations for the installation of embedded parts and anchor bolts by gluing to concrete and protecting them from corrosion" should be followed when installing embedded parts and anchors in reinforced concrete, concrete and stone structures of any purpose during their construction, repair or reconstruction. 1.2. These Guidelines have been developed as a development of the current standards and recommendations for the design of steel embedded parts for reinforced concrete structures and reflect the design features of embedded parts, calculations and the technology of their installation by gluing to concrete.

2. Designs of embedded parts and calculation of their fastening

2.1. Embedded parts can be made in the form of: steel plates with anchor rods welded to them (Fig. 1, a); steel plates attached to concrete with anchor bolts (Fig. 1, b); anchor rod with a ring, plate or hook for fastening communications or equipment (Fig. 1, c); steel plates attached to concrete using through anchor bolts fixed on the lining (Fig. 1, d).

Rice. 1. Embedded details:

1 - steel plate; 2 - anchor rod; 3 - anchor bolt;

4 - washer; 5 - nut; 6 - hole; 7 - anchor rod with ring

for fastening; 8 - overlay

2.2. The thickness of the steel plates is determined by the formula (1), but it must be at least 5 mm:

where d is the diameter of the anchor rod or bolt; R s - design tensile strength of steel anchor rod or bolt; R sq - design shear strength of steel plate. 2.3. Reinforcing steel of a periodic profile with a diameter of 12-25 mm should be used as anchor rods and bolts. For bolts, it is preferable to use helical reinforcing steel. 2.4. The calculation of concrete for puncturing by anchor rods (bolts) and the determination of the number and diameter of anchor rods are performed in the same way as the calculation when using embedded parts installed in the formwork before concreting the structure. 2.5. When attaching embedded parts to concrete, steel plates are glued along their planes and anchor rods and bolts are glued into the holes (Fig. 2).

Rice. 2. Fastening embedded parts to concrete, reinforced concrete and stone structural elements:

1 - concrete, reinforced concrete or stone element; 2 - glue; 3 - steel plate; 4 - anchor rod; 5 - hole filled with glue; 6 - washer and nut; 7 - anchor bolt; 8 - overlay

2.6. Bonding depth L anchor rods and bolts (see Fig. 2, a, b) it is recommended to assign at least the value calculated by the formula

(1)

where D is the diameter of the cylinder, on the surface of which chipping is checked; m is a coefficient that takes into account the operating conditions and depends on the composition of the adhesive and the depth of gluing the anchor rod; taken according to the table. 1; R in, sh 1 - the calculated shear resistance of the connection is taken according to table. 2.

Table 1

50 or more

The amount of hardener,% of the optimal amount	Coefficient t at bonding depth anchor rod, cm
100 or less
150
200
250

Notes: 1 . Above the line are the values ​​for the "concrete - glue" connections, below the line - "glue - anchor rod". 2. It is recommended to take the optimal amount of hardener introduced into the adhesive composition (% of the mass of epoxy resin): UP-0633M - 16, complex amine - 15, diethylenetriamine - 9. - glue” and “glue - anchor rod”) and assign the appropriate diameter of the shearing cylinder and the design shear resistance of the joint.

table 2

Notes: 1. When calculating for long-term load and endurance, the value of the strength index should be multiplied by coefficients of 0.6 and 0.7, respectively. 2. The strength of the "concrete-adhesive" connection is given in the presence of class B40 concrete embedded parts in the gluing zone. To establish the strength of the connection with concretes of other classes, a correction factor should be entered, taken from Table. 3.

Table 3

2.7. It is allowed to assign the depth of gluing of anchor rods less than that established in clause 2.6. In this case, the number of anchor rods working for pulling out in the most stressed row n sup should be calculated by the formula:

where n is the number of pull-out anchor rods in the most stressed row, determined in accordance with clause 2.4; f(x)- normal distribution function (tabulated);

R qu and R qv - respectively, the average value and the standard deviation of the strength of the anchor rods, MPa;

The depth of gluing of anchor rods is recommended to be set equal to at least 10 rod diameters. 2.8. The gluing depth of a single anchor rod (see Fig. 2, c) must be set at least as calculated by formula (1), while the calculated force Q (kN) should not exceed that calculated by formula (2) and the design shear resistance of the rod:

where d is the diameter of the anchor rod, cm; R in - the design resistance of concrete to axial compression, MPa. When only a shear force is applied to the anchor rod, the gluing depth can be reduced to 7 diameters of the anchor rod, while the calculated shear force should not be more calculated by the formula

where R in, loc - the design resistance of concrete to collapse. 2.9. The diameter of the channel for gluing anchor rods and bolts must be chosen in such a way that during the installation of embedded parts, the rods get into the channels or bolts into the holes of the embedded part, based on the allowable deviations from the design dimensions between the axes of the holes and rods (bolts). It is not recommended to set the channel diameter in such a way that the design layer of glue between the rod and the surface of the channel exceeds 15 mm. fittings. 2.10. If structural elements are directly welded to the steel plates of embedded parts with anchor rods or bolts after gluing, then between the plates and concrete (see Fig. 2), instead of glue, the use of cement mortar laid with a layer of 5-15 mm is provided. 2.11. The fastening strength of steel plates attached to concrete with through anchor bolts (see Fig. 2, d) is checked by conventional methods.

3. Materials and equipment

3.1. For anchor rods and bolts, reinforcing steel of a periodic profile of classes, A-I - A-III, is recommended. The steel grade for anchor rods is assigned depending on the operating conditions of the structures. inclusive, from steel grades Vst3kp2 and Vst3kp2-1, below minus 30°C to minus 40°C inclusive - from steel grades Vst3ps6 Vst3ps6 -1 and Vst3ps6-2. 3.2. For gluing plates and gluing anchor rods, the adhesive compositions given in Table 1 are recommended. 4.

Table 4

adhesive composition	The amount of the component, wt. h.
	Epoxy resin	plasticizer		Hardener			Filler	thixotropic
		Furyl alcohol	dibutyl phthalate		Complex amine	Diethylenetriamine
Glue on epoxy resin ED-20 or EIS-1
Glue on epoxy resin ED-14 or ED-16

The amount of hardener is assigned depending on the required bonding temperature and the values ​​of technological, adhesive and cohesive pot life. Technological pot life is the time during which the adhesive can be applied to the surfaces to be glued or poured into holes; is determined by the appearance of tearing threads when the stick is removed from the glue. The recommended technological pot life of the adhesive is 0.5-2 hours. Adhesive pot life is the time during which the surfaces to be joined are glued together; determined by the loss of adhesion to the glue of the finger. The recommended adhesive pot life of the adhesive is 1-4 hours. Cohesive pot life is the time during which the adhesive gains sufficient strength (polymerization time); determined by testing samples. The recommended cohesive pot life of the adhesive is 6-24 hours. in the laboratory, based on the availability of materials, it is necessary to select the composition of the adhesive and the number of components within those recommended in Table. 4, in relation to the specific conditions of work. 3.3. For priming concrete surfaces before gluing, use an adhesive of the same composition as for gluing, but without filler and thixotropic additive. Instead of a plasticizer or in addition to it, a solvent (acetone or toluene) is introduced into the primer in an amount equal to the amount (by weight) of epoxy resin. 3.4. As channel formers for forming holes for anchor rods in freshly laid concrete, it is recommended to use rubber-fabric sleeves or polyethylene tubes. 3.5. To drill holes for anchor rods in hardened concrete, it is recommended to use a mobile machine IE-1801, equipped with annular diamond drills. ). 3.6. It is recommended to prepare glue in a glue mixer (Fig. 3), designed to obtain glue in small volumes. 3.7. To fill with glue horizontal, upward inclined and going from bottom to top holes, it is recommended to make a device in the form of a syringe. 3.8. To fill the gap between the concrete element and the steel plate of the embedded part, to which the structural elements are directly welded, it is recommended to use a cement-sand mortar with a mobility of 2-3 cm and with a water-cement ratio of not more than 0.45, prepared on cement grade not lower than 400.

Rice. 3. Glue making machine:

1 - stand; 2 - guide racks; 3 - hook, fixing the position of the agitator in the non-working position; 4 - lever; 5 - electric motor; 6 - guide clip; 7 - mixer; 8 - container with glue; 9 - collar; 10 - bed

With a vertical position of the steel plate, it is allowed to use a more mobile solution, provided that the required frost resistance of the solution is ensured.

4. Preparation and gluing of embedded parts

4.1. The quality of gluing embedded parts is ensured by the correct selection of the composition of the adhesive, good preparation of concrete and steel surfaces for gluing and compliance with the work technology. 4.2. Before gluing, steel plates are cleaned of rust and scale with emery or sandblasting. It is not allowed to store cleaned plates for more than 8 hours before gluing. Anchor rods and bolts must be cleaned of rust with a steel brush or other methods. 4.3. Before gluing, concrete surfaces are cleaned of dirt and dust with metal brushes and blown with compressed air. Surfaces contaminated with oils (for example, when using fatty lubricants for processing formwork panels) must be treated with a 10% caustic soda solution, rinsed with a strong stream of water, dried and clean with metal brushes or rinse twice with a 5% hydrochloric acid solution (at a consumption of 150 g of solution per 1 m 2), dry and brush. 4.4. Holes for gluing anchor rods and bolts are blown with compressed air. 4.5. The components of the adhesive are thoroughly mixed (the chemicals must be mixed before dosing, and the filler and the thixotropic additive are dried and sifted). and then with filler. The compound is hung in small containers, the capacity of which is designed for single use. The hardener and the thixotropic additive are dosed in an amount corresponding to the container with the compound, introduced in the amount necessary to ensure the required viscosity of the adhesive (making sure that it does not flow out of the holes, gaps between the concrete and the plate); at the construction site, the compound is thoroughly mixed first with the hardener , and then with a thixotropic additive until a homogeneous mass is obtained. 4.6. The following technology for installing embedded parts with anchor rods is recommended (see Fig. 2, a): they clean the concrete surface, holes and steel plate; prime the concrete surface and holes, dry the primer for 2-4 hours; install the embedded part dry and determine the necessary glue layer thickness; fill holes with glue; apply glue on the concrete surface with a layer of 2-3 mm and on the plate with a layer of the required thickness; install the plate in the design position, achieving glue extrusion from the holes and around the entire perimeter of the plate; fix the embedded part in the design position for cohesive pot life of the adhesive. 4.7. The following technology for installing embedded parts with anchor bolts and single anchor rods is recommended (see Fig. 2, b, c): clean the holes for the anchors; prime the holes and dry for 2-4 hours; fill the holes with glue; install anchor bolts or rods , achieving glue extrusion from the holes; fix the anchor bolts (for example, by wedging them in the holes) in the design position during the cohesive life of the glue; clean the concrete surface (including from glue smudges) and the steel plate; install the embedded part dry and determine the required thickness glue layer; apply glue on the concrete surface with a layer of 2-3 mm and on the plate with a layer of the required thickness; set the plate in the design position, achieving glue extrusion along its entire perimeter; fix the plate in the design position with the help of nuts during the cohesive viability of the glue; tighten the nuts . 4.8. If the holes were not provided in the manufacture of the elements, then they are drilled with a special tool. 4.9. The following technology is recommended for installing embedded parts with anchor rods or bolts with a horizontal position of steel plates, to which structural elements are directly welded: clean the holes for anchors; prime the holes and dry for 2-4 hours; fill the holes with glue; cement mortar and level it on the concrete surface; install the embedded part in the design position; fix the embedded part in the design position during the cohesive viability of the adhesive. 4.10. The following technology is recommended for installing embedded parts with anchor rods or bolts with the steel plates in a vertical position, to which structural elements are directly welded: clean the holes for the anchors; prime the holes and dry for 2-4 hours; fill the holes with glue; install the embedded parts in the design position with a gap relative to the concrete surface, achieving glue extrusion from the holes; fix the embedded part in the design position during the cohesive viability of the glue; wash the gap with water; caulk the gap along the lower and side edges of the steel plate; prepare a flowable cement mortar and fill the gap with it, pouring the solution from above through a funnel or by pumping from below. 4.11. The following technology for installing embedded parts with through anchor bolts is recommended (see Fig. rice. 2, d): clean the concrete surface, holes and steel plates and plates; prime the concrete surface and holes and dry for 2-4 hours; install the embedded part dry and determine the required thickness of the adhesive layer; apply glue to the concrete surface with a layer of 2-3 mm and on the lining with a layer of the required thickness; install the lining in the design position, achieving glue extrusion around the entire perimeter of the lining; fix the lining with anchor bolts; fill the holes with glue; apply glue to the concrete surface with a layer of 2-3 mm and on the plate with a layer of the required thickness; install plate to the design position, achieving glue extrusion around the entire perimeter of the plate, tightening the nuts; withstand during the cohesive viability of the glue; tighten the nuts on the anchor bolts. cement mortar (works are carried out in accordance with paragraphs / paragraphs 4.9 and 4.10).

5. Quality control of gluing embedded parts

5.1. Tests of samples in order to check the quality of gluing embedded parts are carried out after establishing the presence of a bead of glue around the entire perimeter of the embedded part. 5.2. Samples are made by gluing concrete cubes and steel plates (Fig. 4) using the same technology and the same adhesive composition as when gluing embedded parts. The samples are tested for shear along the bonding plane. The breaking shear stress must be at least 2.5 MPa.

Rice. 4. Scheme of the sample and the shear test of the “concrete-adhesive-steel” joint:

1 - concrete cube measuring 10 ´ 10 ´ 10 cm; 2 - steel plate

size 2 ´ 10 ´ 12 cm; 3 - glue line; 4 - gasket 2 cm wide,

6. Protection of embedded parts against corrosion

6.1. The method of anti-corrosion protection of embedded parts and materials are prescribed, guided by the relevant regulatory documents, taking into account the purpose of the embedded part, its operating conditions, and the design of the unit with embedded parts. 6.2. The technological process of anti-corrosion protection includes the following main operations: degreasing the surfaces of the embedded part; removing welding spatter, burrs, processing edges; cleaning the surface from scale by the jet-abrasive method or using grinding mechanisms; cleaning the surface from rust by the jet-abrasive method or corrosion converters; application of a material providing corrosion protection in accordance with the selected protection system; drying of the protective material after application of each layer. 6.3. Embedded parts installed in a concrete structure may have a protective coating for interoperational or operational purposes, which is determined by further operations that the embedded part is subsequently subjected to (welding, concreting, etc.). 6.4. To degrease the surfaces of embedded parts, they are washed with alkaline solutions specially prepared in hot water (70-75°C). The composition of the solution (per 1 liter): soda ash (GOST 5100-85E) - 10-12 g; trisodium phosphate - 5-3 g. Rinse the surface to be cleaned, immersing the parts in the solution; if they are heavily soiled, they are wiped with hair brushes and then washed with water. The quality of cleaning must correspond to the first degree of degreasing of surfaces according to GOST 9.402-80. The surface cleaned from fatty contaminants must be hydrophilic. mud. 6.5. The surface of the plates of embedded parts must be cleaned of scale and oxides. Surface cleanliness class - the second. Visual inspection should not reveal scale, rust, etc. 6.6. The roughness of the surface prepared for anti-corrosion coating should be 40-60 microns. 6.7. It is preferable to clean the surface from scale and oxides by the jet-abrasive method or, in the case of outdoor work, by sandblasting. 6.8. For jet-abrasive cleaning, cast-iron chipped shot of the DCHK type No. 0.8 should be used; 1.0; 1.4 according to GOST 11964-81E or quartz sand according to TU IES 54/14-89 with a grain size of 0.7-2.0 mm and a moisture content of not more than 5%. 6.9. With a small amount of work to clean the plates, you can use pneumatic brushes with a reversible head UPRShch-1, manual steel brushes according to TU 1-4-23, ShchPS according to TU 102. 10.78, hammer and chisel. After processing with a manual or mechanized tool, the surface to be treated must be blown with air. 6.10. Rust can be removed by pickling the metal with pickling pastes or corrosion converters. 6.11. The pickling paste is applied with a spatula, plastering spatula, etc. The metal surface is kept under the pickling paste for 1-6 hours, washed with water and dried. The recommended compositions of the pastes are given in Table. 5. Consumption of pickling paste per 1 m 2 of surface 2-3 kg, passivation - 1.0-1.5 kg.

Table 5

Composition (appointment) of the paste

Amount of component, % mass

Holding time, h

Subsequent Operations

Pickling (rust removal):			Rinsing, passivation
Orthophosphoric acid
Sulfuric acid
Hydrochloric acid
Inhibitor (PB-5, catapine, etc.)
Petrov's contact
Water
Sulfite cellulose lye
Diaphragm earth (tripoli)
Passivation (treatment after rust removal with pickling paste): Caustic soda			Washing, drying
Sodium dichromate (or potassium)
Sulfite cellulose lye
Diaphragm earth (tripoli)
Water

6.12. Rust converters are treated with corrosion products tightly adhered to the metal surface, with a layer of up to 100 microns. EVA-01-GISI (TU 81-05-121-78), produced by the Orgsintez plant and Belmestbytkhim production association; MS-0152 (TU 6-10-100-86-77), produced by the Leningrad NPO "Pigment"; EP-01 80 (TU 6-10-1658-82), produced by Soyuzkraska enterprises; acid rust modifier No. 3, produced by associations of Metbytkhimprom; EP-0199, manufactured by the Odessa Paint and Varnish Plant. Primers - rust converters, which are multicomponent systems, are prepared immediately before use (the proportions are indicated in Table 6).

Table 6

EVA-01-GISI

Component primers	Mass ratio of primer components
Primer base
Phosphoric acid 70%
85%
40%
Hardener No. 1
Zinc

The primer is applied by pneumatic or airless spraying using a paint sprayer, as well as manually (with a brush, roller) at a temperature of at least 5 ° C on the metal surface, cleaned of loose and seam rust and pre-moistened with water. To working viscosity, the primer is diluted with demineralized water (condensate). 6.13. For the purpose of interoperational protection, the plates, on which a long-term protective coating is subsequently applied, as well as metal surfaces in contact with concrete, are coated with MS-067 primers (according to TU 6-10-789-79); EF-0121 (TU 6-10-1499-75); VL-02 VL-023 (GOST 12707-77). 6.14. Paintwork materials (Table 7), metallization coatings, as well as coatings based on bitumen-butyl rubber mastics, chlorosulfonated polyethylene, polyurethane paints, etc. are applied to embedded parts that are in operation in air.

Table 7

Paint material

Regulatory document

Application conditions

TU 6-10-1421-76

Apply over primers of the first group according to SNiP 2.03.11-85

TU 6-10-1568-76

Under the enamels of the first and second groups according to SNiP 2.03.11-85

GOST 8292-85

GOST 9109-81

TU 6-10-1504-75

Apply over primer EP-057, putty EP-0010

Apply over primer VL-02

The first group of materials
Penftalic: Varnishes PF-170 and	GOST 15907-70
PF-171	GOST 5494-71E	GF-0119, GF-0163, PF-020
Enamels PF-115	GOST 6465-76	Apply over primers first
Enamel PF-133	GOST 926-82	groups
Enamel PF-1126 (quick-drying)	TU 6-10-1540-78
Enamels PF-1189	TU 6-10-1710-79	Apply without primer
Primer PF-020	GOST 18186-79
Primer PF-0142	TU 6-10-1689-78
Glyphthalic: Primer GF-021	GOST 25129-82	Under the enamels of the first group
Primer GF-0119	GOST 23343-78	Allowed under enamel perchlorv-
Primer GF-0163	OST 6-10-409-77	nil and on copolymers of vinyl chloride of the second, third groups according to SNiP 2.03.11-85
Alkyd-urethane: Enamel URF-1128 (quick-drying)
Alkyd-styrene: Primer MS-0141 (quick-drying)
Oil paints: Thick oil paints for outdoor use	Applied on red lead on drying oil oksol, on primers GF-021, PF-020, GF-0119
Iron minium thickly grated on drying oil oksol	GOST 8868-76	Under oil paints
Oil-bitumen: Paint BT-177	OST 6-10-426-79	Apply over primers GF-021, PF-020
Nitrocellulose: Enamel NTs-132	GOST 6631-74	Apply over primers GF-021, GF-0163, PF-020, FL-03K
Second group of materials
	Under enamels of the second, third groups perchlorovinyl, on vinyl chloride copolymers, chlorinated rubber
Polyacrylic and acrylic silicone: Enamels AS-182	GOST 19024-79	Apply over primers GF-021, GF-0163, PF-020, FL-03K
Perchlorovinyl and vinyl chloride copolymers: XB-16 enamels	TU 6-10-1301-78	Apply over primers GF-021,
Enamels XB-113 and XB-110	GOST 18374-79	GF-0163, GF-0119, FL-03K, PF-020
Enamels XC-119	GOST 21824-76	Apply over primers GF-021,
Enamels XB-124 and XB-125	GOST 10144-74	GF-0119, FL-03K, PF-020
Third group of materials
Phenol-formaldehyde: Primer FL-03K	GOST 9109-81	Under the colors of the second group
Polyurethane: Enamels UR-175	TU 6-10-682-76	Apply over primers of the third group
Epoxy: Enamel EP-1155 (thick layer)
Putty EP-0010	GOST 10277-76	For epoxy enamels
Primer EP-057	TU 6-10-1117-75	Under epoxy enamels, perchlor vinyl and on vinyl chloride copolymers
Polystyrene: PS-1184 and PS-1186 enamels
Perchlorovinyl and vinyl chloride copolymers: XB-1100 enamels	GOST 6993-79	Apply over primers GF-021,
Enamels XB-124, XB-125	GOST 10144-74	GF-0163, GF-0119, FL-03K, PF-020
Silicone: Enamel KO-813	GOST 11066-74	Apply over primers GF-021, FL-03K, GF-0163, GF-01 19, PF-020

6.15. When protecting metal surfaces using the materials listed in Table. 7, apply 1-2 coats of primer and 1-2 coats of the main paint and varnish material so that the total thickness of the protective coating is 100-200 microns. The estimated service life of the protective paint coating is at least 8 years. coatings must be applied in the following technological sequence: a primer is applied and dried, and then the top layers are applied and dried. 6.17. Coating materials must be mixed and filtered before use. Their viscosity should correspond to the method of application. Approximate viscosity according to B3-4 at 18-22 ° C - 14-22 s. 6.18. It is advisable to apply paints and varnishes by air or airless spraying. The use of the brush method is allowed. 6.19. Paintwork materials must be applied in a continuous layer of constant thickness. The adhesion of the coating must correspond to 1-2 points according to GOST 15140-78. Smudges, bubbles, wrinkling, craters, unpainted areas are not allowed. 6.20. When working with paint sprayers, it is necessary: ​​to place the sprayer nozzle perpendicular to the surface to be painted at a constantly equal distance from it; move the sprayer at a constant speed; apply the paintwork material in successive overlay of strips, without passing twice in one place; monitor the correct ratio of the air supplied to the sprayer and paint: with a lack of air, the paint from the paint sprayer comes in unevenly large splashes, and with an excess - with sharp shocks and a pulsating jet. 6.21. The distance from the paint sprayer to the surface to be painted should be 300-400 mm, the width of the imprint of a flat torch 300-500 mm, round 100 mm. It is preferable to work with a flat torch. 6.22. Metallized coatings are applied directly to the metal surface. The thickness of the coating during hot galvanizing is 60-100 microns, with hot aluminizing - at least 50 microns; during gas-thermal spraying of zinc - 120-180 microns, aluminum - 200-250 microns. The service life of metallization coatings, depending on the metal used for protection and the thickness of the layer, is from 10 to 50 years.

Requirements for metallized coatings

6.23. Metallized coatings are applied manually using a gas flame or electric arc method. The wire used to create a metallized coating must be smooth, clean, without kinks and free from swollen oxides. If necessary, the wire is cleaned of preservative lubrication with solvents, of impurities - with sandpaper No. 0. 6.24. Metallization by hand should be carried out by successive application of mutually overlapping strips. Coatings are applied in several layers, with each subsequent layer being applied perpendicular to the previous one. 6.25. To ensure the high quality of the protective coating, arranged by the electric arc method, the following conditions must be observed: the distance from the melting point of the wire to the protected surface is 80-150 mm; the optimal angle of application of the metal-air jet is 65-80 °; the optimal thickness of one layer is 50-60 microns ;temperature of the protected surface during heating - no more than 150°С. 6.26. For the device of coating by the method of gas-thermal spraying, it is necessary to use installations of gas-flame spraying of the type L-5405A, UN-121, UGPN of the Institute of Electric Welding. O.E. Paton.6.27. The metallization coating must be continuous, uniform in color, without particles of unmolten metal, without cracks, delaminations (bloating), traces of local corrosion. 6.28. Using the method of metallization, it is advisable to protect the open surface of embedded parts operated in a highly aggressive environment. 6.29. Protection of steel reinforcing plates can be made with sealing rubber-bitumen mastic materials "Venta" (TU 21-27-39-77), "Venta U" (TU 21-27-101-83), "BLEM-20", "Germabutil" ( RST Ukrainian SSR 5018-86), which are applied to a surface primed in one layer with a primer (thickness 30-40 microns) with a layer of 1.5-2 mm. The estimated service life of the coating is 20 years. 6.31. During incoming inspection, they check the compliance of materials with the requirements of technical specifications. 6.32. During operational control, they check surface preparation, compliance with the conditions for performing anti-corrosion work (temperature and humidity of the ambient air and protected surfaces, purity of compressed air), the thickness of individual layers and 6.33. During acceptance control of completed protective coatings, their continuity, adhesion to the protected surface and thickness are checked. 34. When performing anti-corrosion work, the requirements of chapter SNiP III-4-80 should be observed. 6.35. When preparing the surface for painting, it is necessary to comply with the safety requirements in accordance with GOST 9.402-80 6.36. All painting work must be carried out in accordance with the requirements of the "Sanitary Rules for Painting Work Using Hand Sprayers" No. 991-72, approved by the USSR Ministry of Health.

7. Extract from the safety instructions for working with epoxy adhesive

7.1. When performing work related to the preparation of glue, gluing embedded parts, gluing anchor rods, you should follow the general safety rules and those outlined below. 7.2. Working with glue based on epoxy resins and their components (hardener, plasticizer, solvent) requires caution and accuracy, as it is toxic, has a harmful effect on the human body. The most toxic component of the glue is hexamethyl-diamine. Therefore, it is recommended in all possible cases to replace it with a less toxic hardener, for example, polyethylenepolyamine, diethylenetriamine, UP-0633M. 7.3. Before being hired, workers must undergo special training and instruction, as well as a medical examination. An otolaryngologist and a dermatologist must be included in the medical commission during regular examinations. Special medical supervision must be carried out during the work. 7.4. Persons with hypersensitivity to substances with sensitizing properties (epoxy resins) are not allowed to work. 7.5. If epoxy resins come into contact with the skin or eyes, wash the skin with soap and water, and the eyes with water and saline, and then consult a doctor. consult a doctor immediately. 7.6. For persons working daily with polymeric materials, a 7-hour working day is established, additional leave and milk in the amount of 0.5 liters per day are provided. 7.7. Auxiliary and amenity premises must comply with the fire safety requirements in accordance with GOST 12.1.004-85 and be equipped with fire equipment in accordance with GOST 12.4.003-75. 7.8. If even a small amount of hardener is spilled, it is necessary to immediately cover this place with sawdust moistened with kerosene, then treat with 10% sulfuric acid, and be sure to rinse with water. Contaminated rags and garbage should be collected in a special bucket and taken out into an iron box outside or buried in designated place. 7.9. When performing work related to the use of epoxy compounds, it is necessary to observe measures to preserve the cleanliness of the environment. 7.10. Responsibility for compliance with safety regulations when working with polymeric materials and fire prevention measures are borne by the direct executor, the production manager and the safety engineer. Installation of embedded elements (details), hereinafter referred to as mortgages, into the concrete body of the pool bowl is the first stage in the engineering work for the construction of the pool. In this article, we consider the installation of mortgages in concrete for a pool with a bypass and a bowl suspended on supports. For other types of bowls, there are features in the installation of mortgages.
As a stage, it is a set of works of a carpenter, a locksmith and a bit of a designer. Sometimes the authorities, as an exception, in the absence of finishers, ask to fill in the mortgage openings. A necessary and obligatory condition for the implementation of all work on the installation of mortgages is:
1. The presence of the mortgages themselves on the object.
In 100% of cases, mortgages bring everything and punctures do not happen only because they are indicated in the Equipment Specification (hereinafter the Specification), and with article numbers.
2. Provision of mortgages with appropriate fittings and pipes.
The most painful place in the logistics of most pool companies. A non-standardized variety of all kinds of mortgages requires an indication of the fittings to be connected in the Specification or the presence of a Fittings Specification as a separate application in the Water Treatment Project. The latter is also a rare occurrence in basin life. Two more solutions are a competent manager or the installer himself. The installer himself happens more often than a competent manager. One "but": the installer does not participate in the logistics process and does not receive money for this, and therefore tries not to succumb to the director's requests to help the transport department. Of course, there is a dependence of the workload of the installer on the system of his payment. This is a separate conversation.
3. It is good that there is a presence of glue and a cleaner.
Having spent all the power of his forces on the selection of transitions and corners for mortgages, the manager forgets about the intermediary between fitting and pipe - pvc glue and his assistant - a cleaner, in the common people - a solvent.
4. The presence of a sufficient amount of plywood 10mm thick.
Having reached the object, the installation forces of the pool company discover the absence of elementary plywood. After a radio message to the "center" back, they receive recommendations with the following content:
- drive to the nearest hardware store, market and stock up on plywood;
- find plywood at the object dump, this is a construction site, after all, there is everything in the waste and garbage.
5. Providing conditions for work: heat, light, electricity.
Frequently occurring conditions : cold, dark and accessible outlet without RCD 50 meters from the pool, and you have an extension cord of 25 meters.
However, in the morning the Sun will help you, but not in the basement.
At the time of plastering the bowls, they try to insulate the room with some devices, then nothing, you can work right at the bottom of the pool.
About the socket. There is, suddenly, an outlet within an accessible radius of your extension cord, but that's bad luck, life is in full swing at a construction site and there is no free outlet. Two options: to de-energize someone with your connection or to have a short double, triple socket.
6. There is one more condition, never stipulated in any Specifications for installation (Attachment to agreement). This is the parking lot of the vehicle during the installation work. It is very psychologically uncomfortable to come to the site and not be able to properly park the car. In addition to the fact that the parking lot should be closer to the place of work, it should not yet cause concern. Just like the soldier who every morning must wind footcloths on a fresh head, so the fitter must work and not worry: how is his vehicle? Did the swamp suck it in, since there is no asphalt and hard surface; whether a tractor or a garbage truck drove into it; Has a concrete block or metal channel fallen off a crane? Installing mortgages requires special attention in the production of work, because it is impossible or problematic to redo after pouring.
7. The availability of tools, appropriate hardware and fasteners, as it were, is silent, since it depends only on the installer.
8. Compliance safety precautions in all its manifestations, the thing is necessary, but "not mandatory", as they say - "at the discretion of the master." Good wording! Hence the message: hire craftsmen. Workplace preparation
Even in ancient Rome they used to say: every installer is worthy of the workplace that he created for himself. The times of Ancient Rome have sunk into oblivion and we have what we have.
Ideally, it would be nice to work on a table that has folding legs, but even this will not fit in every machine. Therefore, everyone decides for himself how to get settled. Someone manages to do everything on a dirty floor, and someone, having run around the entire construction site, finds capital scaffolding five meters long by lunchtime and manages to teleport them to their work area.
In addition to the table, tools, equipment and fasteners are required.
When installing mortgages, the reinforced concrete bowl of the pool itself is included in the workplace. Most mortgages are installed while the installer is at the bottom of the pool, which means that you need to go down to the bottom. The fastest way is to jump from the board. But in the absence of water, it is available only to young legs, and then only two or three times, further from the state of the athlete's physical training. The average installer jumps headlong from the side to the bottom of the pool in very rare cases, and then, in these cases, while flying, he does not respect himself at all. And so that after that there is also a "exit by force" up to the side of the pool? No, we do not need such a sport.
All movements down - to the bottom of the bowl and up - to the side of the pool, are required to be carried out by stairs. For a whole day of work, you are so up and down the stairs that in the evening you move along the steps like a sloth on a tree. The sequence of actions when installing mortgages
The description will begin from the moment of arrival at the object. The previous overcoming of the space between the house and the object, the office (warehouse) and the object was already described earlier . The first thing that is done is looking for the pool itself. By the method of interviewing employees encountered along the way on the territory of the facility. The presence and location of communal amenities is also determined: water, toilet, trash can.
On objects with a large territory, they can be located quite remotely. As an exception, some pleasures may be missing or located on a different construction site. As for garbage, rarely, but it happens, they are guided by the principle: the sheriff does not care about the problems of the Indians.
Embedded elements are always installed in the presence of finishers, who fill them in. And then waterproofing and finishing. Here we will find out from them where the plywood is located, where the mortgages themselves, pipes and fittings are located. Finishers, on the other hand, provide us with prepared openings, without a metal mesh and not cluttered with foreign objects, excess plaster and pieces of concrete.
The next step is dressing in work clothes and carrying - transporting the tool and everything you need to the workplace.
About work clothes
Cheap work suits are only good if you don't work in them. When working, they are immediately torn. The crotch of overalls and trousers is torn, the pockets of jackets are torn, suspenders are torn off. Experience tells us that you can’t find better old jeans and a denim jacket for work clothes, and acquiring an expensive and good pair of work kit is money thrown away. This is because after installing the hydraulic circuit of a medium-sized pool, work clothes will be so stained with glue and torn that they can be safely thrown away. You can call the installer a slob who wipes his dirty hands on himself, but in his defense we will say that PVC bonding technology fittings and pipes does not allow you to put the gluing elements with applied glue to the side and culturally wipe your hands on a special clean cloth. Everything happens quickly: glue is applied and the fitting and pipe are joined, you slow down a little and the glue dries up immediately. Excess glue flows where necessary. The lack of laboratory conditions in the workplace exacerbates everything.
About instrument storage
Installation of mortgages requires the largest number of tools from all types of installation work. If you immediately provide the workplace with everything you need, then during the working day you will save a lot of time on numerous transitions for something forgotten. Here the installers have two approaches. Some people think that everyone should store power tools in their own suitcase, others that one large box on wheels is enough. The former have a bunch of all-size suitcases in the trunk, the latter have only one large tool box. We, of course, exaggerate, the installer's car is completely and completely filled with all kinds of materials. And the larger the car, the more space is lacking. Direct dependence, however, is also a paradox. I want the car to have everything for all occasions. The lack of one transition when installing mortgages entails an additional working day, an additional trip to the facility. You will still be asked to get this passage yourself. We agree to bear the costs only for the purchase of the missing transition. And this is piece work (On financial relations with the employer).
The list mentioned above will allow you not to forget anything at the beginning of work. Everything is not kept in the head. In general, it is better to stick step-by-step list in the trunk. You are just transferring the instrument, but you are already thinking ahead, about the next actions, and in the course of the action you miss the little things.
As if everything is ready to work: there is a table or its likeness, tools, fasteners, plywood, mortgages, pipes and fittings, let's get to work. We also pull the extension cord to the workplace.

What is in the project and what is actually
The first step is to assess the compliance of the number of openings in the bowl with the number in the project. It is important to make measurements of the geometric arrangement of the openings on the sides of the bowl, they cost as in project or shifted in some direction. A large difference in the location of openings of the same type can lead to the fact that mortgages do not line up, they become uneven horizontally. The vertical difference in the installation of mortgages of 1 - 1.5 cm is insignificant. More than, it also "does not affect the speed" if the decoration is mosaic, film, but if it is tiles and large formats, leaving the horizontal line is noticeable with close attention.
A large discrepancy with the project, when the mortgage shift fails to achieve the desired, requires coordination with the management.
Options for resolving the issue by management:
- put as is closer to the project;
- hollow out with a perforator on your own or by the forces of finishers;
- cardinally - to hollow out, to drill with a machine tool in the right place. This option is rarely used, mainly in the subjunctive mood, when, after laying the finish, it is noticed visually. In each individual basin firm, these conflicts are resolved differently. When working in favor of several firms, it is necessary in each case to clarify approaches to solving problematic issues.

Measurement of the required size of plywood panels for mortgages
Openings for mortgages can be limited on all sides by concrete or free from it from above. Let's start with the first case. The size of the plywood is determined by the frontal size of the opening with the addition of margins from all 5 - 7 cm. With poorly formed edges of the opening, the margins increase to cover the flaws and there were no holes for pouring the pouring mixture. For smaller openings, such as nozzles, the top margin can be omitted. This makes pouring easier, because with fields on all sides, you need to make a cutout on top of the plywood and a corresponding strobe for the pouring funnel.
For openings with an open top, a plywood shield can be with an upper field of derived dimensions, but not lower than the level of the side.
Openings in the bottom of the pool bowl require plywood as wide as the mortgage, and 10-15 cm long beyond the edges of the opening on each side.
We write down all the required dimensions of plywood boards with a marking pencil on some kind of mortgage cut off from the cardboard package.

Cutting plywood boards
The plywood sheet has a size of 153x153cm. Other formats are not used or very rarely used.
Plywood is cut starting from large sizes. Small shields are obtained from the remains.
Suboptimal markings for cutting can lead to the fact that there is not enough plywood. They try not to bring extra plywood, apparently considering it wasteful. And it is right.
What to cut? Using a hacksaw is no longer yesterday, but the day before yesterday. Jigsaw or circular saw? If there is no space in the trunk of a car or for the sake of economy, then a jigsaw. If we talk about increasing productivity and saving time and effort, then a circular. A small-format circular, the so-called "parquet", which allows you to operate with one hand, speeds up the process by 2-3 times, without tiring the worker.

Marking cross
To center the mortgage on the shield, a marking cross is drawn on it. The marking cross is applied immediately, even before cutting when marking, or after fastening the shields on the side of the bowl. What to choose? When to draw this cross? If the openings for mortgages are located geometrically exactly according to the project, then you can do it right away. If the openings scatter in different directions, both horizontally and vertically, then when installing the same type of mortgages, you will have to move the plywood to the sides, up and down, in order to bring it into one line and make the intermediate distances approximately the same. At the same time, the plywood shield ceases to block the opening and a reinstallation of the mortgage is required.
The marking cross after installing the plywood on board simplifies the positioning of the mortgages.

Fixing plywood panels on the sides of the bowl
Plywood boards for subsequent marking of the positioning of embedded parts are made with black self-tapping screws 3.2 x 55mm and dowels 6 x 30mm. After installing the shields, we apply a marking cross using a laser level, while making sure that the mortgage falls into the opening and does not go into the concrete.
We remove the shields to install mortgages on them.

Fasteners of the embedded part on the plywood board
Mortgage to plywood is attached with screws 20mm long. More often M6, less often M5.
Mortgages of some circulation, hydromassage nozzles and nozzles of a vacuum cleaner can be placed on plywood in a hole, attracted by the front part or specially written out transitions.
Drilling holes for mounting screws requires skill when marking. If the mortgage is intended for the film, then we drill holes along the clamping flange, we determine only the top and bottom of the mortgage. When there is no such flange, we screw the required number of screws into the mortgage, position the mortgage as it should on the shield, applying pressure on the screws, determining the drilling site. One note: the markup is mirrored.

PVC pipe connection
The PVC pipe is attached to the embedded part by changing from a thread to an adhesive connection. The internal thread in the mortgage corresponds to the external thread of the transition and vice versa.
About sealing materials (see)
The threads are sealed with FUM tape, PVC thread, flax, if the mortgage is metal - with a special glue for threads. The latter, of course, is great, of little labor, but has not yet been tested over the years of operation. Everything is clear with the connections of metal fittings, there is metal on both sides, and the glue seizes upon contact with the metal. How PVC will affect the state of the adhesive in the future is not yet 100% clear. The launch of the 25 meter pool showed that sealing with thread adhesive has the right to life.
The use of flax for PVC transitions is permissible only for the external thread of the transition itself. The reason is that when the linen is wet, it swells and can break the transition. With an external thread, since it is screwed into the mortgage, this does not happen.
Some young installers, believing in modern progress in the production of building materials, use silicone for sealing. And nothing if some special for waterproofing, or even the simplest plumbing.
Basically, FUM tape is used to seal threads in connecting PVC transitions to mortgages.
A small instruction for using the FUM tape
FUM tape is always wound on the external thread. The threads on the mortgages and PVC transitions are always smooth and in the process of winding one onto the other, the wound tape is driven from the thread to the end. Such a threaded connection without a seal will definitely leak. The way out is to make a homemade notch, which can be done with an ordinary mounting knife or some other sharp object. Care should be taken that the thread after applying the notch does not have too large burrs. You can't overdo it in this matter.
We take the external thread in the left hand, it looks horizontally to the right. On the thumb of the right hand, we put on the spool of FUM tape so that by rotating the spool around the thread, the tape unwinds freely. For tight winding, we slow down the rotation of the coil with the rest of the fingers. On the first turn, we again press the end of the FUM tape with the thumb of the left hand to the beginning of the 2nd turn of the thread or the middle of the 1st turn, make a full turn away from us clockwise and press the end of the FUM tape with the next turn. Further, the tape should not be torn off and is wound with an effort that does not allow it to be torn. After winding, you can seal the winding by hand, while being careful - burrs may remain on the thread, you can get hurt. Even a plastic barb can cut through the skin. An important question is about the number of turns. The question has a practical, not a theoretical solution. It all depends on the looseness of the threads of the mortgage and the transition. In order to find out, it is necessary to twist the mortgage and the transition, feeling the degree of weakness, the transition dangles on the thread or sits tightly. There are such transitions that they do not completely wind up at all, only three turns, and then they wedge. It turned out that these Chinese transitions have a conical thread and do not fit anything at all. In accordance with trial tests, we use FUM tape.
They forgot to say that the FUM tape has a different thickness and width, the length is not critical for us. For mortgages, a wide and thick FUM tape is used:16.5 m x 19 mm x 0.2 mm. good tape jumbotape from Unipak, but there are other manufacturers. For a 1 1/2 "thread, 6 - 8 turns are required, and sometimes up to 10 - 12. Here you need to focus on the tightening force. We twist the 1 1/2" thread with your right hand, for right-handed people, with an effort to feel it, we start turning the 2" thread with one right hand, then we switch to two hands and finish with the key, the 2 1/2" thread is twisted with the key at the very beginning. There is no scientific approach to determining the tightening torque of the transition thread due to different manufacturers of embedded and PVC fittings. If the number of mortgages is large, then everything is twisted with a key in order to preserve strength and health. At the same time, for identical mortgages, the number of turns of the FUM tape is determined on the first mortgage.
Gluing pipes into screwed mortgages
The diameter of the pipe is determined by the diameter of the junction insert. The length of the pipe is taken depending on the thickness of the concrete side, so that after pouring the opening, the embedded pipe extends 20 - 30 cm over the side. glue on both surfaces and immediately combine one with the other. Remove excess glue with a brush.
There are two approaches to the amount of glue when gluing. At the first, the glue is applied in such an amount that no excess is formed, a neat bead-roller of glue is obtained. In the second, the glue is applied in a "fair" amount, so that the excess glue displacedmay drip from the external bonding point. The first approach is good, but it is fraught with non-gluing. Changes in sensations for psychological, physiological reasons can contribute to an error in the amount of glue applied. The second approach entails excess glue consumption. You can compare the two approaches during the repair process to eliminate the detected leak. Time for this elimination can be spent 20 minutes, or half a day. Taking into account departure on object is the whole working day. For the output of pipes to the technical room, some mortgages use angles of 90 and 45 degrees.
Grounding of metal mortgages
Mortgages made of metal (stainless steel, brass, bronze) make sense to ground for several reasons. First, the flow of water contributes to the accumulation of static electricity, and the second is that stray currents in the ground surrounding the pool building can cause corrosion of the mortgage metal. Stray currents of high intensity are close to the railway, power lines, pipelines. Together with disinfection, these currents, if they are not drained through grounding, can eat metal not only of mortgages, but also of the bulbs of heat exchangers, ultraviolet, metal pumps, etc.
Almost all metal mortgages have a threaded pin or an M5 or M6 bolt with washers and a nut for connecting the ground wire. However, some mortgages do not have such a device. For example, a 300 W Pahlen embedded lantern does not have a ground connection, while a 300 W Hugo Lahme bronze lantern has one.
All ground wires of all pool equipment, including mortgages, must be connected to the ground bus, a metal tape, which is attached wherever there are ground wire leads. As a rule, a PV-3 wire with a cross section of 6 mm is used for grounding, less often 4 mm, yellow-green. For high-quality contact, crimp lugs are used. In the absence of a thread for connecting the ground wire, the contact of the wire strand with the metal of the mortgage body is carried out using special clamps, tape clamps. Ready-made mortgages are installed in previously made fasteners.
Filling embeds
Filling the openings is a simple matter, but first you need to put the formwork on the back of the pool bowl and have the appropriate pouring mixture.
Usually the formwork is made from the same x10mm plywood as the mortgages themselves. It is also placed on self-tapping screws, the only thing that happens in pieces due to the configuration of the construct and with a hole for the pipe and ground wire.
The plywood shield of the mortgage of a large opening is reinforced with a board or bar so that it does not squeeze out during pouring.
Small openings as a back formwork are laid before pouring with pieces of insulating foam. The slots are filled with sealing foam.
If a small wall does not allow using a puncher to fix the formwork, the plywood is simply bursting with pieces of the board. After the pouring solution has hardened, the finishers dismantle the formwork. Filling the opening of the mortgage is done with a special non-shrinking mixture. In order to reduce the amount of expensive non-shrinking composition, small crushed granite is added. The peculiarity of using crushed granite is that it is necessary to act quickly: the crushed stone is heavy and in the liquid mixture is deposited on the bottom of the mixing tank. If you delay, it does not remain in the fill. In addition, pouring with crushed stone requires a large filling hole. The rest of the features are learned in practice.
To save money, self-confident pool builders use ordinary sand-concrete as a fill, which shrinks during formation, forming cracks. Requires, to some extent, vibration (implemented by tapping with a heavy object on mortgage plywood). Tools and fixtures for filling the openings of mortgages:
- extension wire;
- a container for preparing the mixture;
- a special mixer or perforator with a mixing nozzle;
- ladle plaster;
- homemade funnel from tin, plastic bottle, etc.

Embedded parts are used for the reconstruction of finished monolithic surfaces (when the concrete has already been poured and dried). Embedded structures can be used in the modernization, strengthening of the building, refinement of some part of it. The use of parts provides for additional tools: drilling / pneumatic tool for making holes on the surface. You will need a drill that must match the correct size and diameter of the desired holes.

Mortgage element

This is a metal element (made of steel) that is installed (laid) into structures before the concreting process. The elements can be interconnected by welding and, accordingly, will connect the main monolithic structures, inside of which they were laid.

Scope of application

Parts embedded in concrete are used for the installation of various structures. For example, roads, special equipment, fittings, building materials. In the best case, parts embedded in concrete are used at the stage of pouring / installing surfaces. The structure is welded to the desired installation, and then poured with concrete.

Types of installation

There are two main types of installation: through / blind.

through

It is used when it is possible to drill a hole in the monolith from both sides. Please note that the hole will be visible from the front side of the surface, this may spoil its appearance. The element looks like two plates with a rod attached. The rods are attached (welded) to the plates. Bolts/studs/similar tools can be used as rods. The shape of the plate can also vary, taking the form of a hook, a ring, or another configuration.

blind

Use when the monolith can only be drilled from one side (when you want to preserve the appearance of the monolith). The element (similar to the first type) consists of a plate and a rod. Difference: one-sided thread on the rods. Blind bookmark is divided into the following types:

Jellied

It is also called mortgage bonding. Installation proceeds as follows:

• filled with cement mortar;
• then they are engaged in the installation of rods;
• after installation, the cementing mortar is distributed over the parts;
• details are welded.

Almost any material can be used as a cementing slurry. You can create it yourself from ordinary cement, add polymers or epoxy glue there.

anchor

The principle of operation of the anchor: 1 - hole; 2 - cone-shaped rod; 3 - anchor tube; 4 - nut; 5 - plate.

It differs from the previous method in cost and installation speed, technological simplicity. Instead of plates, an anchor is used (a mechanism that securely fastens parts in monolithic blocks).

• the anchor is made in the form of a pipe, the diameter of which must match the concrete;
• a rod is inserted into it (a thread is applied at one of the ends);
• the anchor with the tube inside begins to be laid into the hole (turning it, fixing it securely).

During reconstruction, it often becomes necessary to install additional embedded parts or restore structures missed during the manufacture. In this case, it is necessary to distinguish between structural embedded parts to which significant forces are not transmitted, as well as embedded parts that perceive significant bending moments and tearing forces.

Rice. 10.56. Strengthening the support of plates:

1 - crossbar; 2-plate; 3- fastening of the strand to the plate; 4 - inclined strand; 5 - thrust table; b - stiffeners; 7 - clamps; c - corner of the support table

The first group includes embedded parts for fixing elements that are installed on load-bearing structures (covering slabs on beams and trusses, beams and trusses on columns, self-supporting walls and wall panels for columns, etc.). These embedded parts experience compressive or slight shear forces and are easily installed using a special metal clamp.

For example, to fix a supporting metal sheet on the surface of a reinforced concrete element (Fig. 10.57), it is enough to expose (chop off) the protective layer at two corner reinforcing bars, weld round shorts or ribs from strip steel to them, and to the latter - a sheet (corner) of a new embedded part . If it is necessary to make the embedded part flush with the concrete surface, a groove is cut in the protective layer, the width of which exceeds the width of the embedded part by 10 ... 20 mm, and the depth - the thickness of the plate by 5 ... 10 mm.

Rice. 10.57. Installation of additional embedded parts in reinforced concrete elements:

a - along the upper plane: b- flush with the surface: 1 - chipped concrete zone, subsequently sealed with cement mortar; 2 - shorty-lining from a round rod; 3 - welds; 4 - additional embedded detail; 5- corner reinforcement of the element; 6 - transverse rods of the frame: 7 - correctable element; 8 - transverse groove for installing an embedded part, subsequently filled with cement mortar; 9 - shorty-laying from strip steel

The plate is pressed into a fresh cement mortar and welded through short pads to the working reinforcement of the frame.

A less time-consuming method of installing structural embedded parts using metal clamps (Fig. 10.58), although it requires more steel consumption. Such embedded parts are made locally from pre-prepared and fitted elements. If it is necessary to arrange rigid joints of crossbars with columns, as well as in case of defects in reinforcement protrusions (misalignment, reduction in diameter and number of reinforcement), female clamps are recommended, the area of ​​\u200b\u200bwhich is equal to the design section of the joint. Side metal strips (Fig. 10.59) are installed in grooves knocked out in the protective layer of concrete, width

Rice. 10.58. Installation of additional embedded parts using clamps:

A- a collar from sheet steel on bolts; b- Same. with holder made of sheet steel; V- Same. with round steel holder; 1 - Juice clamp straps; 2 - the front plate of the collar; 3 - welds; 4 - pinch bolt; 5 - stiffeners; 6 - hole in the wall of the beam to pass the coupling bolt, 7 - rod holder; 8 - sheet holder; 8 - a furrow punched in the concrete surface and subsequently sealed with cement mortar; 10 - corner for attaching additional elements

which are taken 20 ... 30 mm more than the width of the bar, and the thickness is equal to the thickness of the bar itself. The axis of the slats must coincide with the axis of the reinforcement of the crossbars. Then, horizontal plates are welded to the planks, the resulting half-collars are inserted on both sides of the column and connected by welding using butt plates. For connection with the reinforcement of the crossbars in the horizontal plates, cuts are cut with an autogenous slit 4 ... 6 mm wider than the diameter of the reinforcement and the rods are welded into them.

The section of the side rails, horizontal plates and welds is calculated on the horizontal force transmitted to the joint. Uniform transmission of the forces of horizontal sheets to the side strips is ensured if the length of the connecting seam between these elements WITH at least half the distance between the side bars is taken.

During reconstruction, it often becomes necessary to anchor additional reinforcing reinforcement or install new embedded parts in an existing reinforced concrete structure.

Rice. 10.59. Strengthening the joints of the crossbars with the column:

a- in the absence of releases of reinforcement from the column: b- with an insufficient number of releases of reinforcement from the column; 1 - crossbar; 2 - crossbar fittings; 3 - side strap of the clamp; 4 - horizontal bar clamp; 5 - butt plate; 6 - side slots. punched in concrete and subsequently filled with cement mortar; 7 - column; c - places of embedding with mortar; 9 - longitudinal reinforcement of the column; 10 - releases of reinforcement from the column; 11 - thrust bar: 12 - welded search; 13 - gap for concreting

In these cases, it is recommended to drill wells in concrete with a perforator to: a depth of at least 20 reinforcement diameters and seal reinforcement in them with epoxy glue or by vibro-caulking with a rigid cement-sand mixture. On epoxy glue, it is possible to fix reinforcement of a smooth and periodic profile to the horizontal and vertical plane of concrete, as well as to the lower plane located at an angle of 45 ° to the horizon. On a cement-sand mortar, it is allowed to fix the reinforcement only on the horizontal plane of the concrete. A washer is welded to the anchor shorty at the end; caulking of the well with cement-sand mortar is carried out using a special vibrocompactor. The anchoring of the rods in the body of concrete is carried out at a distance of at least 5 diameters from each other and at the same distance from the face of the concrete.

10.9. Reinforcement of crane beams and beamless ceilings

Strengthening of reinforced concrete crane beams can be carried out by building up or partially replacing the old concrete with a new one, with metal elements or in a combined way (reinforced concrete and metal).

The simplest method of strengthening, recommended for minor damage to the flange of a T-beam or I-beam, is the installation of bordering corners on high-strength bolts. At the same time, the upper shelf is cleaned of exfoliated concrete, dust and dirt, washed and poured with plastic concrete on fine gravel.

In case of significant damage to the reinforced concrete shelf, it is reinforced with a metal shelf with stiffeners, and the reinforcement shelf must be securely attached to the beam, and the voids between it and the upper surface of the reinforced concrete beam are carefully filled with cement-sand mortar (Fig. 10.60, c).

An effective way to strengthen crane beams is to install a metal clip (Fig. 10.60.6), outriggers that reduce the span of the beam (Fig. 10.61), and metal trusses.

Rice. 10.61. Reinforcement of the crane beam with sprengel (A) and outriggers (b):

1 - the colony; 1 - Reinforced Salka; 3 - reinforcement of the shelf; 4 - sprengel; 5 - outrigger

Moreover, depending on the degree of amplification, these methods can be used both separately and together.

Rice. 10.62. Reinforcement of beamless ceiling capitals:

1 - Column; 2 - capital; 3 - floor slab; 4 - top. reinforcement strapping: 5 - struts; 6-

lower reinforcement strapping; 7 - clip

In case of violation of the reliability of fastening the crane beams to the column, it is recommended to weld the beams to additional embedded parts that are installed on the column using metal clamps on spring washers. Such reinforcement is required if, after alignment, the top of the crane beam significantly exceeds the level of embedded parts in the columns. The capitals of the beamless ceiling are reinforced with a prestressed metal spatial truss in the form of two closed strappings from the corners, one of which rests on the lower reinforced concrete or metal clip, the second covers the capital around the perimeter in the upper zone, and also by installing four struts (Fig. 10.62).

The prestressing of such a system is carried out by heating the upper trim and welding its elements to the struts in a heated state. Sprengel calculation is performed as a spatial statically determined truss for additional loads that act on the floor capital.

Stretch ceilings are modern designs designed for interior decoration. A panel made of film or fabric is attached around the perimeter of the room to a mounting rail - a baguette. Creates a perfectly flat surface, matte or glossy.

The tension cover material is not strong enough to withstand the load from ceiling lights, cornices and curtains. Therefore, before stretching the film or canvas, mortgages are placed on the base ceiling, to which, after finishing, all the necessary equipment is attached.

Built-in wardrobes are located along the wall. The role of the mortgage in this case is performed by the bearing beam, to which the upper furniture tracks and the ceiling molding are fixed.

To install suspended hoods in kitchens and ventilation communications in bathrooms, special platforms are used. With their help, the exhaust duct is securely fixed under the stretch ceiling film.

A beautiful aesthetic coating of a stretch ceiling will hide communications and fasteners that are unnecessary to the eye. And all the equipment necessary for coziness and comfort can be securely fixed to the supporting structures by means of mortgages.

Types of mortgages

Embedded parts for stretch ceilings differ in purpose:

• for spotlights;
• chandeliers;
• wardrobes;
• hidden eaves;
• strengthening drywall sheets for baguette;
• projectors for home theaters;
• ceiling hoods and ventilation ducts.

They are made from wooden blocks, plywood, plastic or metal. The main thing is that the material tolerates high humidity well. Wooden elements are treated with protective compounds.

Under spotlights, mortgages are cut out from ready-made universal plastic molds. They have the shape of a pyramid, assembled from rings of different diameters or squares. A suitable hole is obtained by cutting off the excess part of the platform.

For chandeliers, more massive embedded parts are needed. They transfer the load from the luminaire to the floor slab or other ceiling structure. You can use a ready-made platform in the form of a ring (less often a rectangle) or make it yourself.

Mortgages for hidden cornices are made of metal profiles or wooden bars. They are designed to fasten a baguette framing a niche in the ceiling, and perceive the load from the section of the tension structure. Therefore, the fastening must be reliable and durable.

Plasterboard slabs will not support the weight of a large area ceiling covering. In this case, profiles or wooden bars are used, which are fixed horizontally to the top of the frame for drywall sheets. They will distribute the load from the stretch ceiling throughout the structure.

Preparatory work before installation of mortgages

To properly mount the parts, you need to determine the height of the stretch ceiling. The bottom of the element should be at the level of the stretched canvas. Therefore, the baguette is first mounted, and then the mortgages are installed. The ceiling film is attached to the mounting rails in various ways:

• glazing bead;
• wedge;
• harpoon;
• clipso system.

It is important to accurately determine the minimum distance from the ceiling slab to the tension cover. It depends on the type of mounted fixtures:

• for point spots - 1 ... 1.5 cm;
• for chandeliers - 3.5 ... 5 cm;
• for lamps with halogen lamps - 10 cm;
• for LED strips - 2 cm.

If the film or canvas is located closer to the floor slab than these distances, then it will not work to mount the desired fixtures. It is most convenient to hide communications, wiring and stuffing of electrical appliances at a height of 5-6 cm.

Before starting work, clean the ceiling from crumbling plaster and cover with an antibacterial primer. This will protect the surface from mold and mildew.

It is necessary to mark all the points where the details will be located:

• spot and pendant lamps, household appliances;
• hidden cornices and curtains;
• wardrobes;
• extracts and more.

It is necessary to foresee everything in advance, because after the installation of the ceiling covering, it will be impossible to add or fix anything.

Mark up with a bright marker or soft pencil. If you plan to install a lot of fixtures, it is more convenient to markup on the floor. The points are marked on adhesive tape, if necessary, their position can be corrected. They are transferred to the draft and then to the finishing ceiling using a laser level.

Smooth and rounded lines can be marked with a masking cord and a tape measure or pattern. Sometimes a plastic baguette is used to draw the arc, it bends well.

The chandelier is usually placed in the middle of the room, spotlights can be placed in a straight or arcuate line. Lighting devices should not be closer than 40 cm from the wall.

Before installing mortgages, all electrical wiring is installed in corrugated channels and boxes or on clamps.

Materials and tools for mounting ceiling embeds

To install fasteners, you need to stock up on the following materials and tools:

• perforator;
• screwdriver;
• ladder;
• mortgages - ready-made platforms or sheets of plastic, plywood, wooden beams or metal profiles, depending on what is to be mounted;
• protector rings;
• quick-drying glue;
• sharp knife;
• suspensions made of metal perforated tape;
• roulette;
• cord;
• hammer;
• screws, dowels, anchors.

You will also need terminal blocks for insulating wires of electrical appliances, clamps for fixing wiring, corrugated tubes.

Small spotlights have low power, so they are usually mounted in groups.

After fixing the baguette on the walls and marking on the surface of the ceiling, the installation of mortgages begins:

1. They pull the cord between opposite walls, wedging it into a baguette. It beats off the lower mark of the bearing element under the lamp.
2. Prepare platforms for lamps - cut off part of it to the desired diameter. It should be slightly larger than the diameter of the appliance.
   
3. Fasten with screws to the part 4 halves of the suspension.
   
4. 4 holes are drilled on the ceiling with a perforator, dowels are hammered.
5. Mount the mortgage, aligning it with the cord.
   
6. The electrical wiring is passed through the hole, the ends are cleaned and insulated. Insert back, forming a loop.
   
7. After the installation of the stretch ceiling, a tread ring is glued at the installation site of the mortgage and a hole is cut out in the canvas.
   
8. Mount the spotlight in the seat, attaching it to the wiring.
   

Installation of the chandelier begins with the marking and preparation of the platform. Usually the lamp is placed in the center of the room. The place for installing the mortgage can be easily defined as the point of intersection of the diagonals of the rectangle.

Fixing chandeliers is carried out on:

• ready platforms;
• mounting hooks;
• crosses;
• homemade mortgages.

Chandeliers weighing up to 12 kg are mounted on ready-made plastic platforms. They are a ring with a hole. The material of the mortgage should not be too flexible so that there is no deflection under load.

More massive lamps are mounted on hooks already in the floor slab, or crosses made of wood treated from decay. A hole for wires is drilled in the center of the structure.

In the same way, a mortgage is mounted for projectors for home theaters. The base of the bracket is attached to it.

Plastic can be replaced with moisture resistant plywood. Cut out a square or circle from it, process the ends with sandpaper. Then the material of the stretch ceiling will not tear from the notches to the details.

The sequence of installation of the finished mortgage under the chandelier:

Mounting on a finished hook is the easiest. Does not require the installation of additional parts, if the chandelier is not too massive. With a large weight and dimensions of the lamp, the hook is strengthened by installing a platform in the form of a plate or a cross. The height is controlled by a stretched cord. Hooks are attached to the ceiling with anchors, and crosses - with studs at 5 points.

Scheme of mounting a chandelier with a hook under on a stretch ceiling

If the sliding wardrobe is built in after stretching the ceiling, it is necessary to provide for the installation of a mortgage under the baguette and the top track of the built-in furniture. A timber beam of 50x100 mm is usually used. You can make a box of LSDP with dimensions of 100x100 mm. It is not recommended to increase the height of the structure, because. it will be difficult to insert sliding doors into the opening.

Installation is carried out as follows:

1. Mark a line on the ceiling under the mortgage, having previously stepped back from the wall at a distance equal to the depth of the cabinet. Usually it is 600 mm.
2. The carrier bar or box is fixed to the ceiling.
3. Mount the baguette for the tensile structure on the side surface of the beam, the guides for the cabinet doors - on the bottom.
4. Stretch the film and insert the doors.
5. If necessary, the gap is closed with a decorative strip.

Sliding wardrobe mounting scheme: on the left without a decorative strip, on the right - with a strip

Sometimes the mortgage is placed under the surface of the film or canvas and the top track for the doors is mounted on top of the coating.

If the furniture is already built in before the ceiling is made, the baguette is fixed to the top bezel of the cabinet.

You can install the embedded beam close to the cabinet, attach a mounting rail to it and mount a stretch ceiling.

The mortgage on the ceiling under the curtain is placed at such a distance from the window that the curtain does not touch the window sill and the heating radiator. If a wooden beam is to be used, its edges and corners are carefully sanded with sandpaper. This will protect the stretched material from tearing.

Installation sequence:

1. Rails are mounted around the perimeter of the room for attaching a film or canvas.
2. Having chosen a place, pull the cord parallel to the window opening between the baguettes on the side walls. It is fixed with wedging.
3. A beam or profile is attached to the ceiling on suspensions, guided by a cord. The lower surface of the mortgage must be strictly at the level of the tension fabric.

After stretching the film, the curtain is installed, making mounting holes through the ceiling material.

A hidden cornice is fixed in a niche, it seems that the curtains are falling from the ceiling. In this case, it is not necessary to make holes in the film or sheet, and the guarantee for the coating material is preserved.

Mortgage installation sequence:

1. Mark out a place for a mortgage. The cornice is attached to the draft ceiling, so the part attachment line will be located with a slight deviation.
2. A beam for mounting a baguette is installed horizontally along the cord.
3. A wall baguette is attached to the element from the side of the window.

Hidden cornice installation scheme

After the installation of a stretch ceiling, a cornice is mounted in a niche.

Stretch ceilings are arranged not only in front rooms, but also in bathrooms and kitchens. In addition to the lamps, ventilation equipment is located there. Mortgages are made of plastic, tk. they operate in high humidity conditions. Ventilation can be carried out in a natural and forced way. In the latter case, special attention should be paid to sealing the joints in order to prevent air from entering the ventilation duct into the subceiling space.

Installation of mortgages for hoods and ventilation boxes is carried out according to the scheme:

1. A baguette is fixed along the perimeter of the room at a height necessary to accommodate communications under the ceiling covering.
2. Mortgage platforms with holes for air ducts are mounted on suspensions or adjustable racks at the previously noted points.
3. Corrugated boxes are securely fixed to the draft ceiling with clamps.
4. Stretch the ceiling film.
5. Glue the tread ring of the desired diameter and cut a hole with a sharp knife.
6. Mount a diffuser or kitchen hood.