RU173486U1 - ELEMENT OF MONOLITHIC CONCRETE COVERING - Google Patents

Abstract

The utility model relates to the field of construction and can be used in the construction of prefabricated monolithic, predominantly ribbed floors. The technical result is to increase the bearing capacity of the beams of the often ribbed prefabricated monolithic floors in comparison with analogues (with the same degree of reinforcement of the cross section), increasing the adhesion strength of concrete with the surface of the metal base, which leads to the possibility of reducing the consumption of flexible reinforcement, designated for use on the basis of strength The specified problem is solved, and the technical result is achieved due to the fact that the element of a monolithic concrete floor contains a base, which is a thin-walled profile with the possibility of installing a reinforcing cage in it, while at least two are made in the area of each of the ends of the profile anchor devices. The base can be made in the form of a U-shaped or C-shaped thin-walled profile.

Description

The utility model relates to the field of construction and can be used in the construction of prefabricated-monolithic, mainly often-ribbed ceilings.

The fixed formwork of often-ribbed precast concrete floors most often includes two main elements: beams, which include a reinforcing cage, and blocks that fill the space between the beams. Beams and blocks are the bearing elements of the formwork and perceive the pressure of the liquid concrete mixture during concreting.

Under the beams, a temporary support system is mandatory mounted, consisting of crossbars and support posts mounted with a certain step, to absorb the load from the freshly laid concrete. The blocks have sufficient strength, but they rely on beams, which in no way can support the entire weight of the concrete mixture without support.

It is known that concrete has high compressive strength and extremely low tensile strength. That is why steel reinforcement, located at the bottom of the concrete section of the beam, frees the concrete from the action of tensile stresses that occur during transverse bending in the lower belt of the beam, perceiving them to themselves. At the same time, compressive stresses act in the upper zone of the beam, with which concrete can easily cope.

The floor beam is a monolithic (concrete, metal, composite, etc.) or hollow (metal, concrete, ceramic, etc.) base with a reinforcing cage installed in it, consisting, as a rule, of longitudinal and transverse, including diagonal fittings. The manufacture of beams with a monolithic base is carried out, most often, in the factory. The manufacture of hollow base beams can be carried out both in the factory and directly at the construction site.

As a hollow metal base of the beams, a C-shaped thin-walled profile can be used, as presented in patent No. 131029 (published on December 20, 2012) for the utility model “Element of monolithic concrete flooring”. A reinforcing cage is installed in the profile, and at least two flat elements that are fastened to the base are installed across the base. These elements are equipped with slots in which the reinforcement passing through them is fixed.

Closest to the claimed utility model is the technical solution described in the patent of the Russian Federation No. 133169 for the utility model "ELEMENT OF MONOLITHIC CONCRETE COVERING" (publ. 10.10.2013). The monolithic concrete floor element contains a base in the form of a U-shaped thin-walled profile having shelves made on the walls of the profile from the outside with the possibility of installing formwork elements on them.

These base designs provide for the installation of blocks of fixed formwork with support on the shelves. The formwork thus assembled is filled with concrete directly at the construction site. The base is a thin-walled bent profile. The smooth inner surface of the profile in contact with concrete does not increase the adhesion strength of the profile and concrete, which leads to the separation of the profile from concrete and, as a result, its displacement along the boundary of mutual contact. Such a shift corresponds to the termination of their joint work and, accordingly, the transfer of tensile stresses to the concrete.

The task to which the development of the claimed utility model is directed is the creation of an element of a monolithic concrete floor, characterized by a simple design, but having increased strength characteristics without significant costs for their implementation.

This problem is solved by introducing into the known device overlapping structural changes that do not require large material costs and based on the operation incorporated in the design and previously unused resources.

The technical result consists in increasing the bearing capacity of a beam of often-ribbed precast-monolithic overlapping in comparison with analogues (with the same degree of reinforcement of the cross section), increasing the adhesion strength of concrete to the surface of the metal base, which leads to the possibility of reducing the consumption of flexible reinforcement assigned for use on the basis of strength calculation .

This problem is solved, and the technical result is achieved due to the fact that the element of a monolithic concrete floor contains a base with the possibility of installing a reinforcing cage in it, where the base is a thin-walled profile, while at least two anchor devices.

The base can be made in the form of a U-shaped or C-shaped thin-walled profile. In a particular embodiment, the profile may include shelves made on the outer walls of the profile.

Anchor devices are rods with a section of any shape in diameter from 5 mm to 40 mm. Mostly from 5 to 20 mm. Mostly from 5 to 15 mm. The number of anchor supports is at least 2 on each side. Preferred is the implementation of 4 to 12 anchor devices on each side. Mostly from 2 to 6 anchor devices. Anchor devices in a particular embodiment may be reinforcement bars or self-tapping screws. Anchoring devices can be mounted both vertically in the bottom of the profile and horizontally in its walls.

Anchor devices are located near the ends of the base, i.e. in the support zone of the future beam, because in this region, during bending, the maximum tangential stresses develop at the interface between the concrete and the profile. Extreme anchor devices are placed at a distance of 50-100 mm from each of the ends.

The specified constructive measure allows the thin-walled profile to be included in the work with lateral bending of the beam as external reinforcement. A profile bonded to the concrete of the beam perceives tensile stresses in the same way as the flexible reinforcement included in the reinforced concrete beam.

Such a constructive solution is the anchoring of the profile in concrete, providing conditions for the perception by the profile of tensile loads acting in the lower zone of the concrete section. When the beam is transversely bent, upon reaching a certain level of stresses, the adhesion of the thin-walled profile to concrete is violated, caused by the development of maximum tangential stresses in the support zone. It is there that the separation of the profile from concrete occurs, as a result, its displacement along the boundary of mutual contact. Anchoring prevents the mutual displacement of thin-walled profile and concrete at the border of their interface.

The claimed design allows to obtain a prefabricated-monolithic overlap with increased bearing capacity in comparison with analogues.

The essence of the claimed technical solution is illustrated by the following drawings, which depict a particular embodiment of the utility model, not limiting the claimed claims:

FIG. 1 is an isometric image of an element of a monolithic concrete floor assembly with a reinforcing cage;

FIG. 2 - image of a fragment of the base with anchors (with reinforcing cage),

Figure 3 - image of a fragment of the base with anchors (without reinforcing cage),

FIG. 4 is an isometric image of a monolithic concrete floor element without reinforcing cage;

The figures show an element of a monolithic concrete floor, including a base 1 made of a thin-walled profile of a U-shaped section, containing anchor devices 2 of 4 on each side. Inside the base there is a triangular reinforcing frame 4 mounted in the retainers of the protective layer of concrete 3, fixed by the fixing elements 5. The transverse fixing elements 5 are attached in any way possible to the reinforcing frame 4 and the base 1.

Anchor devices, which are self-tapping screws or bolts with nuts, are mounted in the required places in a thin-walled profile in the required quantities. It is possible to use reinforcing bars fixed in the profile in any way possible.

The beam is assembled both in the factory and at the construction site.

Base 1 is fixed to the assembly table. Anchor 2 are mounted near the ends of the base. The triangular reinforcing cage 4 with the clamps of the protective layer of concrete 3 mounted on the rods of the working reinforcement is installed inside the profile. The latches 3 limit the possibility of movement of the frame vertically down and in the transverse direction. Also, the frame 4 is fixed with metal elements 5, which are welded to the walls of the base and to the frame itself. When assembled, the beam of prefabricated-monolithic overlap has sufficient rigidity necessary for the implementation of transport and loading operations and installation at the facility, as the triangular frame is a spatial truss.

The thin-walled profile constructively forms the lower boundary of the beam, i.e. it is the best possible way, geometrically located in the section for the perception of tensile stresses. In this case, a thin-walled profile, firmly bonded to the concrete of the beam, will experience tensile stresses and perform the function of external reinforcement until its integrity is violated, i.e. before the break. The inclusion of a thin-walled profile (previously performing only the formwork function, as in the case of the above analogues) will, in some cases, abandon the reinforcing cage if the load-bearing capacity of the overlap is provided only by external reinforcement of the beams.

Claims (10)

1. An element of a monolithic concrete floor containing a base with the possibility of installing a reinforcing cage in it, characterized in that the base is a thin-walled profile, with at least two anchor devices made in the region of each of the ends of the profile. 2. An element of a monolithic concrete floor according to claim 1, characterized in that the thin-walled profile has a U-shaped section. 3. An element of a monolithic concrete floor according to claim 1, characterized in that the thin-walled profile has a C-shaped section. 4. An element of a monolithic concrete floor according to claim 1, characterized in that the anchor devices are rods of any shape with a cross section in diameter from 5 mm to 40 mm. 5. An element of a monolithic concrete floor according to claim 4, characterized in that the anchor devices are rods of any shape with a cross section in diameter from 5 to 15 mm. 6. An element of a monolithic concrete floor according to claim 1, characterized in that the number of anchor devices is from 4 to 12 anchor devices on each side. 7. An element of a monolithic concrete floor according to claim 1, characterized in that the anchor devices are reinforcement bars or self-tapping screws. 8. An element of a monolithic concrete floor according to claim 1, characterized in that the anchor devices are attached vertically to the bottom of the base. 9. An element of a monolithic concrete floor according to claim 1, characterized in that the anchor devices are attached horizontally to the walls of the base. 10. An element of a monolithic concrete floor according to claim 1, characterized in that the anchor devices are placed at a distance of 50-100 mm from each of the ends.

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