RU196649U1 - LONG-DIMENSIONAL STEEL-CONCRETE ELEMENT WITH LONGITUDINAL ELECTRIC FITTINGS - Google Patents

Abstract

The technical solution relates to the field of steel-concrete products and structures used in various fields of technology, in which an external reinforced metal frame concrete layer is used as a protective and heavier coating structure. The task is to create a long-length steel-concrete element (concrete metal pipe), which provides when connected to the structure the required accuracy of positioning the cable channels interconnected. EFFECT: provision of alignment of cable duct openings entering and leaving a long-length steel-concrete element when using longitudinally spiral twisted reinforcement with rod reinforcement fixed to it, forming a three-dimensional metal frame. This is achieved by the fact that a long-length steel-reinforced concrete element includes a steel pipe with a concrete blasting installed on it by means of spacers of reinforcing cage of longitudinally spiral twisted reinforcement with oriented at an angle to the generatrix of the reinforcing bars, to which tubular cable ducts of polymer material are fixed on the pipe side with the location of their input and output parts behind opposite ends of the applied concrete layer, the cable ducts being fixed with an angular offset along the length relative to the reinforcing bars, compensating for the deviation longitudinal reinforcing bars, and between the reinforcing cage and the outer surface of the concrete layer continuously twisted along the length of the steel-concrete element with tension of twine made of polymer mat series. A twine made of polypropylene was used as a twine, which is wound in a spiral with several, preferably 4-6, threads with a pitch between them of 140-190 mm, filed with their tension in the spray zone of the concrete mixture, and the step between the cable channels should be at least 30 mm from the condition of the possibility of penetration of the concrete mixture and its uniform distribution as a result of spraying. In this case, the fastening of each cable channel at the ends of the frame is made at three points on each side with a step smaller than in the middle part. Tubular cable channels can be additionally fixed to the rods of the longitudinal reinforcement to stabilize their position during the concrete process. 3 s.p. f-ly, 6 ill.

Description

The technical solution relates to the field of steel-concrete products and structures used in various fields of technology in which an external concrete layer reinforced with a metal frame is used as a protective and heavier coating structure.

Known long pipe element containing a concrete core and reinforcement in the form of a closed outer shell having radial holes, the shell is made in the form of a steel pipe along the entire length of the element and is provided with an external protective coating, made with the possibility of preventing concrete from escaping from the holes of the shell when concreting the core (RU No. 2641142, 01/16/2018).

A product is known in the form of an inner pipe conducting a substance in a gaseous or liquid state, a ballast coating applied coaxially to the inner pipe to form an annular space and having a length shorter than the inner pipe, a central tube made of dielectric is installed over the longitudinal weld of the inner pipe materials and mounted in a ballast coating for cable installation, and protruding beyond the edge of the ballast coating, and at least one same tube to the left and to the right of the main oh tube equidistant, the distance between the tubes is not less than 75 mm for pipes with a diameter of less than 500 mm and not less than 100 mm with 500 mm diameter or more (RU №2648171, 12.10.2017).

Known concrete steel pipe with a cable channel, obtained by placing a steel pipe on an assembly stand, installing a reinforcing cage along its surface, consisting of longitudinal and annular reinforcement rods, centering the reinforcing cage relative to the pipe using clamps, placing on the cable channel cage in the form a protective tube, placing the pipe in the mold and pumping the concrete mixture into the space between the pipe and the mold (RU No. 2647257, 03/15/2018).

The closest known one is a long-length steel-concrete element in the form of a concrete steel pipe with a cable channel, obtained by installing a steel pipe with an anti-corrosion coating on the assembly stand, placing and fixing a reinforcing cage on its surface, placing and fixing along the cable channel reinforcing cage in the form a protective tube, placing a protective shell over the assembled structure and injecting concrete mixture into the annulus through the installed end faces for plugs, while the protective tube of the cable channel is fixed along the reinforcing frame with a knitting wire or ties (RU No. 2616681, 04/18/2017).

Known long-length steel-concrete elements do not provide the required accuracy of cable channel positioning when connecting them to the structure, since with their length of 10-12 m, an error accumulates with respect to the accepted reference base, which in practice are longitudinal seams of longitudinally welded steel pipes, since according to the requirements of 9.4.2 SP 86.13330.2014 approved by order of the Ministry of Construction and Housing and Communal Services of the Russian Federation of February 18, 2014 N 61 / pr and entered into force on June 1, 201 4 g, longitudinal seams must be displaced relative to each other by a distance of at least 75 mm for pipes with a diameter of up to 530 mm and at least 100 mm for pipes with a diameter of 530 mm and more, respectively, depending on the diameter of the pipe, the distance between the tubes may not be less than 75 mm for pipes with a diameter of less than 530 mm and at least 30 mm with a diameter of more than 530 mm. When the reinforcing cage is longitudinally twisted (in the form of a continuous spiral) with longitudinal reinforcing rods fixed on it, they deviate from the parallelism of the longitudinal axis of the metal pipe in the direction of winding of the continuous reinforcement due to the transfer of stresses in the spiral reinforcement arising from it upon winding.

The objective of this technical solution is to create a long-length steel-concrete element (concrete metal pipe), which, when connected to the structure, provides the required positioning accuracy of the cable channels connected to each other.

The technical result consists in reducing the deviation of the cable channels entering and leaving the long-length steel-concrete element when using longitudinally spiral twisted reinforcement with rod reinforcement fixed to it, forming a three-dimensional metal frame.

This is achieved by the fact that the long-length steel-concrete element includes a steel concrete-coated by spraying pipe with a reinforcing cage of longitudinally spirally reinforced reinforcing bars mounted on it with spacers and with reinforcing rods oriented at an angle to the generatrix, to which tubular cable channels made of polymer material are fixed with the location of their input and output parts behind the opposite ends of the applied concrete layer, and the cable channels are fixed with angular displacement relative to the length of rebars, compensating the deviation of the longitudinal rebars, and between the reinforcing frame and the outer surface layer of concrete continuously along the length of the reinforced concrete element is wound with a tension of twine from a polymeric material. A twine made of polypropylene was used as a twine, which is wound in a spiral with several, preferably 4-6, threads with a pitch between them of 140-190 mm, filed with their tension in the spray zone of the concrete mixture, and the step between the cable channels should be at least 30 mm from the condition of the possibility of penetration of the concrete mixture and its uniform distribution as a result of spraying. Moreover, the fastening of each cable channel at the ends of the frame is made at three points on each side with a step smaller than in the middle part. Tubular cable channels can be additionally fixed to the rods of the longitudinal reinforcement to stabilize their position during the concrete process.

A causal relationship of the features with the indicated technical result is ensured in the long-length steel-concrete element by the fact that the straightness of the position of the cable channels in it is affected not only by their fastening to the reinforcing cage with compensation for the angular deviation from the reinforcing bars, as well as fixing the position attached to them due to additionally pressed with their concrete mixture in the process of spraying it. The preload was carried out by applying twine made of a polymeric material in a spiral to the twisting zone, which prevents rebound of the concrete mixture components and forms an elastic reinforcing layer that uniformly compresses the concrete mixture around the cable channel. Such compression ensures stabilization of the position of the cable channel also due to the elastic properties of polypropylene, and the fibrous structure of its threads provides a connection between the layers of deposited concrete in the area of the spiral twisted reinforcement and the upper layer of the concrete-reinforced concrete element, eliminating any displacement of the elements located in the concrete. The number of strands of spiral twisted polypropylene twine (4-6) and the pitch between them (140-190 mm) are selected from the condition of penetration between them and subsequent retention of the ingredients by the sprayed concrete mixture. With a decrease in the step size, penetration of the concrete mixture is difficult, and with an increase, the rebound of the applied concrete mixture from the pipe surface increases significantly. This embodiment provides the required alignment of the cable channels at the beginning and at the end of the lengthy steel-concrete element.

In FIG. 1 shows a longitudinal section through a long element;

In FIG. 2 is a section along AA in FIG. 1, (in the example, the step between the cable channels is 100 mm);

In FIG. 3 - spiral-twisted metal frame with rod longitudinal reinforcement;

In FIG. 4 - site weld joint spiral frame and rod longitudinal reinforcement;

In FIG. 5 is a diagram of an arrangement of a cable channel in a steel-concrete element;

In FIG. 6 - photo of a long-length steel-concrete element before spraying of concrete mixture and twine winding (reinforcement and cable channels location are shown).

The long-length steel-concrete element is a steel pipe 1 with a reinforcing cage 3 installed on it by means of spacers 2. The reinforcing cage (length L) is made of reinforcing bars 4, spiral-wound longitudinally with pitch h, with reinforcing bars oriented at an angle to the generatrix 5. To the reinforcement from the side the pipes are secured with tubular cable channels 6 made of polymer material with the location of their input and output parts at opposite ends of the applied concrete layer, preferably in mandrels. Cable channels 6 are fixed with an angular offset along the length relative to the reinforcing bars 5, compensating for the deviation (angular) of the longitudinal reinforcing bars 5 from the parallelism of the generatrix of the metal pipe. A layer of concrete mixture 7 is applied to the metal pipe 1 with an insulating coating by spraying. The concrete mixture was applied by counter-rotating rolls, capturing during their rotation the concrete mixture supplied from the hopper and throwing it onto the previously wetted pipe surface through the cells of the reinforcing cage 3. Moreover, in the process of applying the concrete mixture to the pipe 1 is continuously twisted along the length of the steel-concrete element with tension of twine (not shown in the drawings) from a polymer material with the formation of Zor between the turns, which is applied in the concrete mix. Twine prevents the backward rebound of concrete mixture falling onto the surface of the pipe. Since the supply of twine is carried out in the supply zone of the concrete mixture, it remains in the concrete layer, providing a bond of the inner concrete layer and the concrete surface layer applied to the pipe under the reinforcing cage. In the process of winding the twine from the bobbins, it is tensioned, thereby further compacting the already applied inner layer. The presence of twine along the entire length of the concrete coating of the pipe acts as a damper in the concrete and reduces cracking and reduces the likelihood of destruction of the concrete layer due to stresses arising in it. Twine made of polypropylene, for example, according to GOST 17308, which is wound in a spiral with several, preferably 4-6, threads with a pitch between them of 140-190 mm, filed with their tension in the spray zone of the concrete mixture, was used as twine. The presence of twine on the pipe during the concreting process also prevents the displacement of tubular cable channels, stabilizing their spatial position. The step between the cable channels should be at least 30 mm from the condition of the possibility of penetration between them of the concrete mixture and its uniform distribution as a result of spraying. The fastening of each cable channel at the ends of the frame is made, for example, with a knitting wire, at three points on each side of it with a step smaller than in the middle part. To stabilize their position during the process of concrete coating, tubular cable channels can be additionally fixed to the rods of longitudinal reinforcement.

Claims (4)

1. A long-length steel-concrete element comprising a steel-concrete-sprayed pipe with a reinforcing cage made of longitudinally spirally twisted reinforcing bars mounted on it by spacing supports with reinforcing rods oriented at an angle to the generatrix, to which tubular cable ducts of polymer material are fixed with an arrangement their input and output parts for opposite ends of the applied concrete layer, characterized in that the cable channels are fixed with an angular offset along ine relatively rebars compensating the deviation of the longitudinal rebars, and between the reinforcing frame and the outer surface layer of concrete continuously along the length of the reinforced concrete element is wound with a tension of twine from a polymeric material. 2. A long-length steel-concrete element according to claim 1, characterized in that the twine is made of polypropylene, which is wound in a spiral with several, preferably 4-6, threads with a pitch between them of 140-190 mm, filed with their tension in the spray zone of the concrete mixture, and the pitch between the cable channels is at least 30 mm. 3. A long-length steel-concrete element according to claim 1, characterized in that the fastening of each cable channel at the ends of the frame is made at three points on each side with a step smaller than in the middle part. 4. A long-length steel-concrete element according to claim 1, characterized in that the tubular cable channels are additionally fixed to the rods of the longitudinal reinforcement in order to stabilize their position during the concrete process.

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