RU132103U1 - REINFORCED CONCRETE BOARD WITH MORTGAGE PARTS - Google Patents

Abstract

1. Reinforced concrete slab with embedded parts, containing monolithic concrete and having at least one lower row of working reinforcement in the form of parallel rods installed along the length of the slab, characterized in that the embedded parts located along one of the longitudinal sides and / or short sides plates, placed on horizontal and vertical surfaces of the plate with minimum distances between the centers of the plates of embedded parts S = 1 + 2h, and the minimum distance in the light between the reinforcing bars of the lower row z = 1.33kb, where 1 p long side of the fixing plate; h is the distance from the upper edge of the plate to the center of the reinforcement of the lower row; b - the largest grain size of a large aggregate concrete mixture; k is a coefficient taking into account the grain size of the large aggregate of the concrete mixture. 2. Reinforced concrete slab according to claim 1, characterized in that the number of reinforcing bars of the upper row is less than the number of reinforcing bars of the lower row.

Description

The utility model relates to construction, namely to the construction of reinforced concrete slabs with embedded parts and mounting loops.

Known prestressed concrete slab for floor slabs according to the patent for the invention of the Russian Federation [1]. A prestressed slab for floor slabs includes tensile and non-tensile reinforcement, as well as lightening voids parallel to the long side of the slab. At the same time, voids are placed in the upper three quarters of the plate thickness, and in the lower quarter of the plate thickness there are additionally circular channels or recesses of parabolic section for tensioning the reinforcement, oriented perpendicular to the facilitating voids and located parallel to the smaller side of the plate and to each other. The centers of symmetry of the channels are located in one plane in the middle of the height of the lower quarter of the plate, and the axis of the parabolic recesses is perpendicular to the lower surface of the plate. The technical result consists in the formation of floor disks, large-span shells, various sites from packages of prestressed multi-hollow reinforced concrete slabs.

However, this technical solution does not allow for reliable sealing of embedded anchors designed for fastening fencing floors, coatings, slabs of balconies, loggias, terraces, service sites, bridges under the conditions of safe operation of buildings and structures. The presence of voids in the cross section of the slab reduces the fire resistance of the structure and does not allow for the length and depth of embedment of the branches of the mounting loop in concrete, thereby limiting the conditions of loading and unloading and installation work; in addition, on the supporting sections of the slab, additional structural measures are necessary to ensure the strength of the supporting sections of the structure.

Known reinforced concrete hollow slab according to the application for the invention [2]. Reinforced concrete hollow core slab can be used as a load-bearing prefabricated element of floors and internal walls, as well as load-bearing and non-load-bearing panels of external walls and walls of volumetric blocks of the “pipe” type. The inventive hollow plate is equipped with continuous transverse ribs, mainly end, made with technological holes. Introduction to the design of reinforced concrete hollow core slabs of continuous transverse ribs, mainly end edges, can significantly improve both the support of hollow core slabs on brick walls and the perception by hollow core slabs of forces from upstream walls; expand the scope of hollow core slabs - use hollow core slabs with vertical voids as elements of load-bearing internal walls and as elements of load-bearing internal walls and as walls of volumetric blocks of the “pipe” type; reduce concrete and metal consumption of ceilings and walls; improve the performance of exterior wall panels; increase the fire resistance of structures and buildings from them. The implementation of end ribs with technological holes allows you to freely remove from the voids thermoplastic material without loss, as well as to pass through the holes and voids air, heated or cooled, to seal the voids.

However, the presence of voids does not allow ensuring the strength of embedment in concrete of anchors of embedded parts of fences of floors, coatings, slabs of balconies, loggias, terraces, service areas, bridges required under the conditions of reliable and safe operation of buildings and structures, as well as to ensure the length and depth of launch of the branches of the installation hinges in concrete; reduces the fire resistance of the structure; additional structural measures are required on the supporting sections of the slab in order to ensure their strength; in addition, the stove is difficult in technical implementation.

Known multi-hollow reinforced concrete slab according to the patent for the invention of the Russian Federation [3]. Achievable technical result - reducing the material consumption of the plate. A multi-hollow reinforced concrete floor slab, including an upper shelf reinforced with a metal mesh, a lower shelf reinforced with a metal mesh and rod longitudinal reinforcement, separated in the longitudinal direction by voids of constant cross section, while the shape of the section of voids is taken in the form of a rectangle connected together with rounded corners at the lower base and a semi-ellipse, so that the upper base of the rectangle coincides with the long axis of the ellipse; the vertical dimensions of these voids determine their conditions for the location of the load-bearing reinforcement in the lower shelf of the plate and the necessary area of the compressed zone in the upper shelf of the plate, and horizontally - from the condition of non-collapse of the upper concrete arch after compaction and excavation of the hollow formers (punches), while before fixing the punches on To the shuttering formwork they wear plastic film covers.

However, the slab is difficult in its technical implementation and, in addition, the presence of voids does not allow ensuring the strength of the embedded anchors in the concrete of the embedded parts of the fencing of ceilings, coatings, slabs of balconies, loggias, terraces, service areas, bridges, required by the safe operation of buildings and structures; fulfill the requirements of the standards for the length and depth of the launch of the branches of the mounting loop in the concrete slab; requires the implementation of structural measures in the supporting zones of the slab in order to ensure their strength; reduced fire resistance of the structure.

Common disadvantages of the known prefabricated reinforced concrete floor slabs include:

1) the inability to ensure the length of the embedment of anchors for embedded parts for fastening fencing floors, coatings, slabs of balconies, loggias, terraces, service sites, bridges, internal openings of civil and industrial buildings and structures [7], [8];

2) the impossibility of meeting the requirements of the standards for the length and depth of the launch of the branches of the mounting loop in concrete in connection with the presence of voids in the cross section of the slab [7], [8];

3) the need to perform additional structural measures on the supporting sections of the slabs with voids [4];

4) technological difficulties in the manufacture of structures containing voids;

5) the presence of voids in the cross section of the plate reduces the fire resistance of the structure.

The technical result achieved by the utility model is to increase the strength of anchoring of reinforcement of embedded parts of reinforced concrete slabs; improving the reliability of fencing floors, coatings, slabs of balconies, loggias, terraces, service sites, bridges of civil and industrial buildings and structures; in ensuring the safety of the operation of structures; in ensuring the length and depth of the launch branches of the mounting loops in the concrete slab; in creating universal conditions for supporting reinforced concrete slabs on supporting structures.

The technical result is achieved due to the fact that embedded parts located along one of the longitudinal sides and / or on the short sides of the plate are placed on horizontal and vertical surfaces of the plate with minimum distances between the centers of the plates of the embedded parts S _m = 1 _m + 2h _o , and the minimum distance in the light between the bars of the bottom row reinforcement is z = 1.33 kb, where 1 _m is the size of the long side of the plate of the embedded part; h _o - the distance from the upper face of the plate to the center of the reinforcing bars of the lower row; b - the largest grain size of a large aggregate concrete mixture; k is a coefficient taking into account the grain size of the coarse aggregate, and the number of reinforcing bars of the upper row is less than the number of reinforcing bars of the lower row.

The list of figures: figure 1: plan of a reinforced concrete slab with embedded parts (top view); figure 2: section 1-1 of figure 1; figure 3: section 2-2 of figure 1; figure 4: section 3-3 of figure 1; 5: mounting loop 4; 6: embedded part 5, side view; Fig.7: view 1-1 of Fig.6; Fig: view 2-2 of Fig.6; Fig. 9: stress distribution diagrams σ in monolithic concrete 1 of a reinforced concrete slab; figure 10: detail of the fastening of the guard rails to the embedded parts of the reinforced concrete slab.

Positions in figures 1-10 indicate: 1 - monolithic concrete; 2 - bottom row reinforcement; 3 - reinforcement of the upper row; 4 - mounting loop; 5 - embedded part; 6 - the upper surface of the reinforced concrete slab; 7 - the lower surface of the reinforced concrete slab; 8 - vertical surface of the long side of a reinforced concrete slab; 9 - coarse aggregate concrete mixture; 10 - vertical surface of the short side of the plate; 11 - metal plate of the embedded part 5; 12 - anchor embedded parts 5; 13 - welds for connecting the plate 11 and the anchors 12; 14 - rack fencing reinforced concrete slab; 15 - the bottom plate of the racks 14; 16 - a weld connecting the rack fence 14 and the bottom plate 15; 17 - a weld connecting the lower plate 15 with the plate 11 of the embedded part 5.

Description of the construction of reinforced concrete slabs with embedded parts.

Reinforced concrete slab consists of: reinforced concrete 1, reinforcement of the lower row 2, reinforcement of the upper row 3, mounting loops 4, embedded parts 5, the upper surface of the reinforced concrete slab 6, the lower surface of the reinforced concrete slab 7, the vertical surface of the long side of the reinforced concrete slab 8, the vertical surface is short sides of the plate 10. The embedded part 5 consists of: a metal plate 11, anchors 12, welds 13 for connecting the plate 11 and anchors 12.

The minimum distances between the centers of embedded parts 5 S _{m are} determined so that the stresses σ in the reinforced concrete slab concrete arising from the action of vertical and horizontal loads on the fencing of floors, coatings, slabs of balconies, loggias, terraces, service areas, bridges of civil and industrial buildings and structures, were distributed in the slab section according to the shape of a truncated pyramid, the sides of which are inclined at an angle of 45 °, and the upper base is the side 1 _{m of the} plate 11 of the embedded part 5, and the lower the base of the pyramid passes along the axis of the reinforcement 2 of the lower row:

S _m = 1 _m + 2h _about ,

where 1 _m is the size of the long side of the plate embedded parts; h _o - the distance from the upper face of the plate to the center of the reinforcing bars of the lower row.

The minimum distance in the light between the rods 2 of the reinforcement of the lower row z is determined in such a way as to ensure high-quality concrete mix of the space between the rods 2 of the reinforcement taking into account the largest grain size of the large aggregate of concrete mixture b and the cement sheath

z = 1.33kb,

where b is the largest grain size of a large aggregate concrete mixture;

k is a coefficient taking into account the grain size of the coarse aggregate.

Table 1 presents the coefficients k, which are taken depending on the largest grain size of coarse aggregate b.

Table 1 The largest grain size of coarse aggregate b 5 10 twenty thirty 40 fifty 60 70 k 3,760 1,880 1,075 1,078 1,128 1,052 1,065 1,074

Plate function

Reinforced concrete slab installation is carried out by an assembly crane. Reinforced concrete slab rises for stationary mounting loops 4 using inventory lifting devices (traverses, slings, etc.) and is installed on supporting structures.

I. Supporting reinforced concrete slabs on supporting structures

The support of a reinforced concrete slab is made depending on the type of supporting structure.

1. Support reinforced concrete slab - brick walls. Reinforced concrete slabs are laid on brick walls with a cement-sand mortar. After checking the correct position of the slab, the wall is anchored [6]. An anchoring of a brick wall is performed by welding the bent end of the anchor connection with the mounting loop 4 of the reinforced concrete slab, and the other, the bent end of the anchor connection is welded to the release of the reinforcement from the wall. In the figures, supporting structures are not shown.

2. The support of the reinforced concrete slab on the reinforced concrete structures (crossbars, cantilever beams, columns, etc.) is carried out by welding the plate 11 of the embedded part 5 of the reinforced concrete plate and the embedded part of the supporting structure. Welded joints should be made immediately after mounting the plate. In the figures, supporting structures are not shown.

3. Supporting a reinforced concrete slab on metal structures. The plate 11 of the embedded part 5 of the reinforced concrete slab is welded to a metal supporting structure without additional connecting elements. In the figures, supporting structures are not shown.

II. Installation of racks of fences 14 floors, coatings, slabs of balconies, loggias, terraces, service areas, bridges of civil and industrial buildings and structures

The bottom plate 15 of the guard post 14 is welded to the plate 11 of the embedded part 5 of the reinforced concrete plate with a weld 17.

III. Corrosion protection of plates 11 embedded parts 5, anchor ties, mounting loops 4 and welds 16, 17

Corrosion protection methods are selected depending on the operating conditions of the reinforced concrete slab [5]:

1. Plate 11 of the embedded part 5, anchor connection, mounting loop 4, welds 16, 17 are not concreted and not monolithic. Ways of corrosion protection: hot dip galvanizing; cold galvanizing with zinc-filled compositions; combined coatings (cold galvanizing with zinc-filled compositions and weatherproof coatings);

2. Plate 11 of the embedded part 5, anchor connection, mounting loop 4 and welds 16, 17 are concreted or monolithic. In this case, prior to concreting or monolithic protection, the indicated elements are protected by hot galvanizing or cold galvanizing with zinc-filled compositions.

Bibliography

1. Pre-stressed plate for floor slabs. Patent for invention RU No. 2338851. Publication date 11/20/2008.

2. Reinforced concrete hollow slab. Application for invention RU No. 93054549. Publication date 05/20/1996.

3. Hollow core concrete slab. Patent for invention RU No. 221809. Date of publication 10.12.2004.

4. GOST 9561-91. Multi-hollow reinforced concrete floor slabs for buildings and structures.

5. SP 28.13330.2012. Protection of building structures from corrosion. Updated edition of SNiP 2.03.11-85. - M., 2012.

6. SP 15.13330.2012. Stone and armored constructions. Updated edition of SNiP P-22-81 *. Ministry of Regional Development of the Russian Federation. - M., 2012.

7. SP 52-101-2003. Concrete and reinforced concrete structures without prestressing reinforcement. - M., 2004.

8. A guide for the design of concrete and reinforced concrete structures made of heavy concrete without prestressing reinforcement (to SP 52-101-2003). Central Research Institute of Industrial Buildings, NIIIZhB. - M.: Central Research Institute of Industrial Building OJSC, 2005.

Claims (2)

1. Reinforced concrete slab with embedded parts, containing monolithic concrete and having at least one lower row of working reinforcement in the form of parallel rods installed along the length of the slab, characterized in that the embedded parts located along one of the longitudinal sides and / or short sides plates, placed on horizontal and vertical surfaces of the plate with minimum distances between the centers of the plates of embedded parts S _m = 1 _m + 2h _o , and the minimum distance in the light between the reinforcing rods of the lower row z = 1.33kb, where 1 _m - the size of the long side of the plate embedded parts; h _o - the distance from the upper face of the plate to the center of the reinforcement of the lower row; b - the largest grain size of a large aggregate concrete mixture; k is a coefficient taking into account the grain size of a large aggregate of concrete mixture. 2. Reinforced concrete slab according to claim 1, characterized in that the number of reinforcing bars of the upper row is less than the number of reinforcing bars of the lower row.

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