RU2476313C1 - Method of making carbon-tube-concrete structure - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to construction, namely, to method of fabricating carbon-tube-concrete structures. Proposed method comprises producing two-layer blank closed along its lengthwise edges from carbon fiber with exposed crosswise edges, securing tightly blank end edges, creating overpressure between blank layers to make closed cylindrical blank from carbon fiber, and impregnating cylindrical shell wall with polymer materials. Prior to releasing said overpressure, concrete mix layer is sprayed onto outer walls of said cylindrical blank to make outer protective layer of circular cross-section. Then, after applied outer layer is cured, pressure is released to make inner working layer of circular cross-section on fitting said cylindrical shell of concrete-based carbon fiber there inside to distribute it uniformly over the surface of said cylindrical shell of carbon fiber by centrifugal forming.

EFFECT: higher efficiency.

3 cl, 8 dwg

Description

The invention relates to the construction of buildings and structures and can be used in the manufacture of carbon concrete structures, namely piles, piles, shells, columns and racks of the frame for buildings and engineering structures.

A known method of manufacturing a carbon-concrete structure, including preparing the surface of the finished reinforced concrete structure, applying an adhesive composition to it and gluing continuously along the entire length of the construction of long carbon fiber tapes at a slight angle to the horizontal axis to create an external carbon fiber cage [Shilin A.A. External reinforcement of reinforced concrete structures with composite materials. - M.: Publishing House "Stroyizdat", 2007].

The disadvantage of this method is the use of manual labor, which leads to an increase in the complexity of work, manufacturing time, the need for special stands and equipment for free access to the entire surface to be treated, as well as the difficulty in controlling the quality of the construction. In addition, this method can only be used as reinforcement of reinforced concrete structures.

The closest in technical essence is a method of manufacturing a carbon-concrete structure, including the manufacture of a two-layer closed along the longitudinal edges of the workpiece with open transverse edges of carbon fiber, tightly securing the end edges of the workpiece on mandrels of annular cross-section, creating excess pressure between the layers of the workpiece to form a closed cylindrical shell of carbon fiber, impregnation of the wall of the shell with polymeric materials, followed by filling all of it interior concrete under pressure to form a continuous concrete core [Jessica Bloch, Kevin Miller. BRIDGE TO THE FUTURE? // Bangor Daily News, Saturday / Sunday, February 21-22, 2009. bangordailynews.com].

The disadvantage of this method is the production of work directly at the construction site, as a result of which additional costs arise for the use of special equipment (vibroinstallation, crane, concrete mortar pump, etc.), for power consumption, as well as the availability of special conditions for storing manufactured structures until the required concrete strength is achieved solid concrete core. In addition, with this method there is no quality control of filling the shell with concrete, i.e. determination of the possible formation of caverns, which significantly reduce the bearing capacity of the finished structure.

The objective of the invention is to develop a method of manufacturing a carbon-concrete structure that allows you to transfer the entire manufacturing process to factory conditions that contribute to improving quality and reducing labor intensity. The technical result is to obtain, at the end of the process, a carbon-and-concrete concrete structure ready for production without the formation of a carpet, which has all the advantages of prefabricated reinforced concrete structures (quick installation, no formwork and wet process at the construction site). In addition, the method eliminates the additional work of protecting a closed cylindrical shell of carbon fiber after fabrication of the structure and makes it possible to produce a carbon-concrete structure of lower mass without reducing the bearing capacity.

The objectives are achieved in that the method of manufacturing a carbon-concrete structure includes the manufacture of a two-layer carbon fiber workpiece closed along the longitudinal edges with open transverse edges, tightly securing the workpiece end edges, creating excess pressure between the workpiece layers to form a closed cylindrical carbon fiber shell from it, impregnation of the wall of the cylindrical shell with polymeric materials, removal of excess pressure. New in this method is that prior to relieving excess pressure, a layer of concrete mixture is applied by spraying onto the outer walls of the closed cylindrical shell of carbon fiber. The result is an outer protective layer of annular cross-section. Then, after a set of strength of the applied outer layer, excess pressure is removed and the inner working layer of the annular section is formed. For this, a mixture of concrete is loaded inside a closed cylindrical shell made of carbon fiber and its uniform distribution along the contour of a closed cylindrical shell made of carbon fiber is carried out by centrifugation.

As a mixture for the formation of the outer protective layer and the inner working layer of the annular cross section, carbon fiber concrete is used.

In addition, for the manufacture of a carbon-concrete structure with increased compressive strength, the inner working layer of the annular section is formed so that a spatial framework made of reinforcing steel is successively installed inside the carbon fiber shell, then the concrete mixture is loaded, and then the centrifugation method is applied.

The proposed method of manufacturing a carbon-concrete structure transfers the entire manufacturing process to the factory environment, which helps to improve quality and reduce labor intensity, as well as obtaining a complete factory readiness at the end of the process, which has all the advantages of precast concrete structures, as well as the possibility of using such structures as compressed and eccentrically compressed elements. In addition, this method eliminates the additional work of protecting a closed cylindrical shell of carbon fiber after the manufacture of the structure.

The essence of the invention is illustrated by drawings, where:

figure 1 presents hermetically securing the end edges of a two-layer carbon fiber preform with end mandrels (plugs) and connecting a compressor;

figure 2 - the formation of a closed cylindrical shell of carbon fiber by creating excess pressure inside a two-layer preform of carbon fiber;

figure 3 - the formation of the outer layer of the annular cross section by applying a mixture based on concrete, such as carbon fiber concrete, by spraying on the outer surface of a closed cylindrical shell of carbon fiber with the formation of a semi-finished product in the form of a tubular element;

figure 4 - laying a mixture based on concrete, such as carbon fiber concrete, inside the semi-finished product in the form of a tubular element;

figure 5 - the formation of the inner layer of the annular cross section by the method of centrifuged formation of it from a mixture based on concrete, for example carbon fiber concrete, with the formation of carbon-concrete structure;

figure 6 - installation of a spatial cylindrical frame made of reinforcing steel inside the semi-finished product in the form of a tubular element;

in Fig.7 - laying concrete mixture inside the semi-finished product in the form of a tubular element;

on Fig - the formation of the inner layer of the annular section of reinforced concrete by centrifugation with the formation of carbon-concrete structure of increased bearing capacity for compression.

A method of manufacturing a carbon-concrete structure consists of several stages. The ends of the two-layer carbon fiber preform 1 with open transverse edges are hermetically fixed to mandrels 2 of circular cross section, in one of which a fitting for supplying compressed air is located, and a compressor is connected (Fig. 1).

Then, overpressure is created inside the two-layer preform of carbon fiber 1 to form a closed cylindrical shell of carbon fiber 3 from it (FIG. 2), after which the walls of the closed cylindrical shell of carbon fiber 3 are impregnated with polymeric materials, for example, epoxy resin.

Then, without removing the excess pressure inside the closed cylindrical shell of carbon fiber 3, a layer of a mixture based on concrete, for example carbon fiber concrete 4, 2.5 cm thick, is applied to its outer surface by spraying. As a result, an outer protective layer of an annular section from carbon fiber concrete 4 is formed (Fig. 3).

After the strength of the outer protective layer of the annular cross section is made of carbon fiber concrete 4, the excess pressure inside the closed cylindrical shell of carbon fiber 3 is removed and a semi-finished product is obtained in the form of a tubular element 5, consisting of a closed cylindrical shell of carbon fiber 3 and the outer protective layer of the annular section with a thickness of 2.5 cm from carbon fiber concrete 4. A semi-finished product in the form of a tubular element 5 is mounted on a centrifuge and a mixture based on concrete, for example carbon fiber, is loaded inside it ETOH mixture of 6 (Figure 4). The volume of carbon-fiber-concrete mixture 6 depends on the required thickness of the inner working layer of the annular section made of carbon-fiber-concrete 7 created from it.

Then, a centrifuged process of forming the inner working layer of the circular section from carbon fiber concrete 7 is carried out in a centrifuge. As a result, a carbon-concrete concrete structure of the circular section of full factory readiness 11 is obtained, consisting of successively arranged layers of the circular section: the outer protective layer of carbon fiber concrete 4 with a thickness of 2.5 cm, a closed cylindrical shell of carbon fiber 3 and the inner working layer of carbon fiber concrete 7 (figure 5).

To increase the bearing capacity of the carbon-concrete structure for compression inside the semi-finished product in the form of a tubular element 5, a spatial cylindrical frame made of reinforcing steel 8 is placed, the position of which is fixed by mandrels of the circular section (plugs) 2 (Fig. 6).

Then, the concrete mix 9 is loaded inside the semi-finished product in the form of a tubular element 5 (Fig. 7). The volume of concrete mixture 9 depends on the required thickness of the inner working layer of the annular section made of reinforced concrete 10 created from it.

Then, in a centrifuge, the process of centrifuged formation of the inner working layer of the annular section of reinforced concrete 10, consisting of a spatial cylindrical frame of reinforcing steel 8 and concrete mixture 9, is carried out (Fig. 8). The result is a carbon-reinforced concrete structure of the ring section of full factory readiness 12, consisting of successively arranged layers of the ring section: the outer protective layer of carbon fiber concrete 4 with a thickness of 2.5 cm, a closed cylindrical shell of carbon fiber 3 and the inner working layer of reinforced concrete 10, consisting of in turn, from a spatial cylindrical frame made of reinforcing steel 8 and concrete mixture 9 (Fig. 8).

Thus, the proposed method allows in the factory to produce a carbon-concrete structure of the required diameter (from 0.2 m to 2.0 m or more) in the form of a precast element with a length of 0.5-6.0 m, which can be used as a beam, columns, piles, shell piles or a separate linear element for, for example, polygonal arches and torus. Also, the proposed method helps to improve the quality and reduce the complexity, eliminates the formation of caverns.

A positive feature of the proposed method is the formation of a protective layer of carbon fiber in the manufacturing process of carbon-concrete construction. In addition, the proposed method allows to produce a carbon-concrete structure of a lower mass without reducing the bearing capacity, in contrast to the carbon-concrete structure made by known methods.

The proposed manufacturing method allows to increase the compressive strength of a new carbon-concrete structure by introducing flexible steel reinforcement into joint operation, which allows the use of a new carbon-concrete structure in structures experiencing significant loads.

Claims (3)

1. A method of manufacturing a carbon-concrete structure, including the manufacture of a two-layer carbon fiber workpiece closed along the longitudinal edges with open transverse edges, hermetically securing the end edges of the workpiece on a circular mandrel, creating excess pressure between the workpiece layers to form a closed cylindrical carbon fiber shell, impregnating the wall cylindrical shell with polymeric materials and pressure relief, characterized in that prior to overpressure removal the outer protective layer of the annular section is formed, for this, a concrete-based mixture layer is applied to the outer surface of the closed cylindrical shell of carbon fiber by spraying, after which the strength is increased, the pressure is removed and the inner working layer of the circular section is formed, while inside the closed cylindrical shell of carbon fiber load the mixture based on concrete and carry out centrifugation. 2. A method of manufacturing a carbon-concrete structure according to claim 1, characterized in that they form the outer protective layer and the inner working layer of the annular section of carbon fiber concrete. 3. A method of manufacturing a carbon-concrete structure according to claim 1, characterized in that they form an inner working layer of annular cross-section of reinforced concrete, for this purpose they load concrete mixture into a cylindrical shell of carbon fiber and additionally install a spatial frame made of reinforcing steel.

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