KR102373355B1 - Manufacturing method of ultra-high-strength square beam using centrifugal casting device - Google Patents

Abstract

The present invention relates to a method for manufacturing a square beam with ultra-high strength using a centrifugal molding device, which improves productivity. The method of the present invention comprises the steps of: arranging and fixing a plurality of T-beams at regular intervals; sealing an inlet; allowing a prestress to be introduced; curing a centrifugally molded square beam; and demolding and transferring the centrifugally molded square beam.

Description

Manufacturing method of ultra-high-strength square beam using centrifugal casting device

The present invention uses the centrifugal molding method, which is a production method of large-diameter PHC piles, to reduce the hollow ratio of the cross-section to 10% or less in the factory manufacturing of the prestressed beam, so that the watertightness is improved, the cross-section is dense, and the durability is excellent, It relates to a method of manufacturing an ultra-high-strength prismatic beam using a centrifugal forming device capable of manufacturing a plurality of section steel members to be embedded in a centrifugal forming process to facilitate connection or synthesis with a slab.

Since centrifugal molding is manufactured by centrifugal force using only the outer mold instead of the inner mold when forming the tube, the excess moisture in the concrete is expelled to the ash side during the molding process, and the concrete settles, so the watertightness is high, and the compressive strength is generally 10~ more than 30% higher.

The members produced by centrifugal molding have high strength, excellent durability due to watertightness, and high density of materials according to centrifugal force, so that they can be produced without voids appearing on the existing PC surface, and have the advantage of being manufactured in a factory to ensure uniform quality. have it Efforts to manufacture various structural members by centrifugal molding are continuing at home and abroad, and in particular, the technology for manufacturing pillar members for buildings by centrifugal molding is in the stage of being developed and put into practical use in Korea by several companies.

Overseas countries where centrifugal columns are widely used are widely used in advanced European countries such as Germany and Austria, where labor costs are high in construction environments. In particular, it is actively used as a building pillar in Europe, and there are cases where it is also used for beams in some cases. The manufacturing length is about 15m, and it can be manufactured up to 35m. For these columns, the post-tension method is additionally applied in some cases to secure the buckling length. In terms of shape, unlike in Korea, it is understood that not only various symmetrical shapes such as circles, side sections, and rectangles, but also axially symmetrical shapes such as ovals can be produced.

In Korea, the fields where centrifugal molding technology is mainly applied are piles and electric poles, and the application to buildings has only recently begun. Currently, centrifugal columns are applied to around five sites led by an engineering company, and some buildings used on the ground floor have been constructed using products used for PHC piles.

In Korea, as the labor cost continues to rise, the use of high-strength PC members is expected to increase, and competition for developing centrifugal molded members with high added value from existing PHC pile producers has already begun. However, due to manufacturing difficulties, production or field application of angular beams, which are bending members, has not been found in Korea so far. The advantages of high strength, durability, and high quality precast products obtained through centrifugal molding have not yet been utilized in structural beams.

Republic of Korea Patent No. 10-2044713

Therefore, the present invention was invented to solve the above problems, and it is possible to manufacture the prestressed beam in a factory using the centrifugal forming method, which is a production method of large-diameter PHC piles, and to reduce the hollowness of the cross section to 10% or less to achieve watertightness. Ultra-high-strength prismatic beam using a centrifugal forming device that can be manufactured so that a plurality of section steel members that are high in height and have a dense cross-section, which has excellent durability, and facilitates connection or synthesis with other adjacent members or slabs, are embedded in the centrifugal forming process It is an object to provide a manufacturing method.

As a means for solving the above problems, the method for manufacturing an ultra-high-strength prismatic beam using the centrifugal forming apparatus of the present invention (hereinafter referred to as "the manufacturing method of the present invention") is divided into two in parallel along the longitudinal direction, and In the method of manufacturing a prismatic beam using a centrifugal forming apparatus comprising a centrifugal rotating die composed of a separate upper and lower formwork and having a pouring space formed therein, H-beams are respectively disposed on one side and the other side of the upper formwork, Placing and fixing a plurality of T-beams at regular intervals between both H-beams (step S10); In the pouring space, the end finishing plate is inserted up to the section set for each H-beam, and a fixing plate with a tension bar formed in the center is disposed at a position spaced apart from each H-beam, and then a plurality of strands or a plurality of strands are placed along the longitudinal direction of the pouring space. connecting and fixing the steel bars between both fixing plates (step S20); The lower formwork is mutually coupled to the upper formwork, and the sealing plate is connected so that the tension bars of the fixation plate pass through the open ends of the centrifugal rotating formwork. sealing the inlet (step S30); Tensing the tensile bar exposed to the outside through the sealing plate to introduce prestress in a batch or stepwise manner to the plurality of strands or the plurality of steel rods by the flow of the fixing plate in the pouring space (step S40); Centrifugally molding the centrifugal rotating mold to form a hollow in the center of the prismatic beam (step S50); Curing the centrifugally molded prismatic beam by steam-drying the centrifugal rotary mold on which the centrifugal molding is completed (step S60); and separating the upper and lower molds of the centrifugal rotating formwork to demold and transfer the centrifugally-formed prismatic beam from the pouring space (step S70).

As an example, in step S10, in the upper formwork, a plurality of fastening holes are formed through the bottom surface of the space portion in contact with the flanges of the H-beams and T-beams, and the flanges of the H-beams and T-beams face the fastening holes. A fastening bolt that penetrates through a fastening hole and is exposed to the outside is formed in the region to be fixedly coupled by nut fastening from the outside of the upper formwork. It is characterized by being

As an example, in the step S10, the upper formwork has a plurality of cut-out holes formed at regular intervals along the bottom surface of the space portion in contact with the flanges of the H-beams and T-beams, and the flanges of the H-beams and T-beams have the cutouts. It is characterized in that the horizontal shear reinforcement exposed to the outside through the incision hole is coupled to the part facing the ball.

As an example, in the step S20, the edge of the end closure plate is characterized in that the anti-slip border is formed of an elastic material to the outside in which the slope is formed.

As described above, the manufacturing method of the present invention is excellent in quality as a square beam is manufactured in a factory using a centrifugal molding device, and is excellent in durability due to high watertightness due to centrifugal molding production, and prestress is introduced while using ultra high strength concrete (100 MPa or more) By securing the strength having a non-cracked structure as a result, it has the advantage of being able to achieve a low height and securing the building limit of the structure.

In addition, the prismatic beam manufactured by the manufacturing method of the present invention minimizes painting by exposing only the horizontal shear reinforcing bar while the unit section steel member for connection with the member such as an adjacent column or upper slab is embedded and synthesized inside. Standardization has the advantage of improving productivity because the production cost of the parish is low.

And, when constructing beam members in a long-span structure, a plurality of section steel members that enable connection with various columns or upper slabs in the field can be manufactured integrally during the centrifugal molding process of square beams at the factory, thereby reducing the construction period. It has the advantage of being shortened and economical compared to the existing steel type or steel composite beam.

1 is a block diagram showing a manufacturing method of the present invention.
Figure 2 is a side cross-sectional view showing the centrifugal molding apparatus used in the manufacturing method of the present invention.
Figure 3 is a perspective view showing a centrifugal forming ultra-high strength prismatic beam manufactured by the manufacturing method of the present invention.
Figure 4 is a perspective view showing a centrifugal rotating die according to an embodiment of the present invention.
Figure 5a is a perspective view showing an upper formwork according to an embodiment of the present invention.
Figure 5b is a perspective view showing a lower formwork according to an embodiment of the present invention.
6 is a perspective view illustrating a section steel member and a coupling structure thereof according to an embodiment of the present invention;
7 is a perspective view showing a prestress introduction structure according to an embodiment of the present invention.
8A to 8F are views showing the manufacturing method of the present invention for each process.
Figure 9 is a schematic view showing an embodiment of the end plate as one configuration of the present invention.
10A and 10B are each embodiment showing a state in which the fastening bolts are exposed in a state in which the upper frame is disassembled.

In describing the present invention, the terms or words used in the present specification and claims are based on the principle that the inventor can appropriately define the concept of the term in order to best describe his or her invention. It should be interpreted as meaning and concept consistent with the technical idea of

As shown in FIG. 1, the manufacturing method of the present invention is a centrifugal molding apparatus including a centrifugal rotating die, which is divided into two in parallel along the longitudinal direction and is composed of an upper and lower mold that are coupled and separated from each other, and a pouring space is formed therein. In the method of manufacturing a prismatic beam using, H-beams are respectively arranged on one side and the other side of an upper formwork, and a plurality of T-beams are arranged and fixed at regular intervals between both H-beams (step S10); In the pouring space, the end finishing plate is inserted up to the section set for each H-beam, and a fixing plate with a tension bar is disposed in the center at a position spaced apart from each H-beam, and then a plurality of strands or a plurality of strands along the longitudinal direction of the pouring space connecting and fixing the steel bars between both fixing plates (step S20); The lower formwork is mutually coupled to the upper formwork, and the sealing plate is connected so that the tension bars of the fixation plate pass through the open ends of the centrifugal rotating formwork, and the opening and closing plate is combined after the concrete is put through the inlet formed in the lower formwork. sealing the inlet (step S30); Tensing the tensile bar exposed to the outside through the sealing plate so that prestress is introduced to the plurality of strands or the plurality of steel rods in batches or steps by the flow of the fixing plate in the pouring space (step S40); Centrifugally molding the centrifugal rotating mold to form a hollow in the center of the prismatic beam (step S50); Curing the centrifugally molded prismatic beam by steam-drying the centrifugal rotary mold on which the centrifugal molding is completed (step S60); and separating the upper and lower molds of the centrifugal rotating formwork to demold and transfer the centrifugally formed square beam from the pouring space (step S70).

That is, the present invention relates to a manufacturing method of a prismatic beam using a centrifugal molding manufacturing method, which is a production method for large-diameter PHC piles of Ø1000mm or more. Prestressed prismatic beams that can replace rigid beams can be manufactured by using ultra-high strength concrete of 100 MPa or more.

Specifically, the manufacturing method of the present invention uses a centrifugal forming apparatus that enables centrifugal forming for the square beam 1 to be realized, and the centrifugal forming apparatus includes a centrifugal rotating die 10 and a centrifugal rotating die 10 as shown in FIG. It may be configured to include a sealing plate 20 , a rotating means 30 , and a plurality of unit shape steel members 40 .

The centrifugal rotating formwork 10 has a pouring space 11 formed therein, and openings 12 communicating with the pouring space 11 are formed at both ends, respectively. And the centrifugal rotating die 10 may have a cylindrical structure to be advantageous for centrifugal molding.

For example, the centrifugal rotating formwork 10 includes an upper formwork 100 and a lower formwork 110 in which space portions having one surface opposite to each other open along the longitudinal direction are provided, respectively, and these upper formwork 100 and the lower form Each of the open surfaces of the formwork 110 may be coupled to face each other, so that the mutual spaces may be combined to form a single pouring space 11 therein.

At this time, the pouring space 11 is a space in which the rectangular beam 1 is manufactured through curing of the injected concrete, and in consideration of demolding of the centrifugal rotating formwork 10, it is preferable that the central portion has a relatively wide hexagonal cross-sectional shape.

That is, each space portion of the upper formwork 100 and the lower formwork 110 is composed of a trapezoidal cross-section that becomes wider toward the opened surface so that the pouring space 11 can have a hexagonal cross-section. This is to facilitate the demolding operation of the formwork 100 and the lower formwork 110 .

The centrifugal rotating formwork 10 is rotated in any one direction by the rotational force applied from the rotating means 30 by connecting the rotating means 30 to be described below, so that the prismatic beam having the hollow part 2 ( 1) centrifugal molding can be achieved.

In addition, it is preferable that the concrete injected into the pouring space 11 of the centrifugal rotating formwork 10 be reinforced in strength by using ultra-high strength (100 MPa or more) concrete, and the load and long-term deflection applied in the long-span structure, etc. A bar prestress can be introduced to effectively resist. For this purpose, a plurality of strands or a plurality of steel rods 140 can be fixed in the pouring space 11 of the centrifugal rotary formwork 10 .

First, the present invention comprises the steps of disposing H-beams 400 on one side and the other side of the upper formwork 100, respectively, and disposing and fixing a plurality of T-beams 410 at regular intervals between both H-beams 400 (step S10) ) has

As shown in FIG. 6, the unit section steel member 40 includes a pair of H-beams 400 to which a flange 401 is fixedly coupled to the bottom surface of the space at one side and the other side of the upper formwork 100, and the It includes a plurality of T-beams 410 to which the flange 411 is fixedly coupled to the bottom surface of the space along a predetermined interval between the pair of H-beams 400 .

That is, the H-beam steel 400 and the T-beam steel 410 may be introduced into the space portion of the upper formwork 100 through the opened surface of the upper formwork 100, and a flange is provided on the bottom surface of the plurality of inner surfaces constituting the space portion. (401, 411) is to be coupled so that the end is exposed on one surface of the prismatic beam (1) by being in close contact.

At this time, the upper formwork 100 has a plurality of fastening holes at regular intervals along the bottom surface of the space in which the flanges 401 and 411 of the H-shaped steel 400 and the T-shaped steel 410 are in contact, as shown in FIG. 5A . 101 may be formed through, and correspondingly, the flanges 401 and 411 of the H-beam 400 and the T-beam 410 are provided with a fastening hole 101 in a portion facing the fastening hole 101. Penetrating fastening bolts 402 and 412 may be protrudingly coupled.

Accordingly, the H-beam steel 400 and the T-beam steel 410 mounted on the bottom surface of the space part are exposed to the outside by the fastening bolts 402 and 412 passing through the fastening hole 101, so that the nut from the outside of the upper formwork 100 is It can be fixedly coupled through fastening, and in the mold demolding process, the upper mold 100 can be separated from the square beam 1 manufactured by separating the nut from the fastening bolts 402 and 412 . These fastening bolts 402 and 412 may be formed separately from the flanges 401 and 411 as shown in FIGS. 10A and 10B or may be formed as an integral component.

After dismantling the upper formwork 100 in this way (step S70), the fastening bolts 402 and 412 are exposed from the flanges 401 and 411, so as to the horizontal shear reinforcement 403 and 413 described below. It is to enable the horizontal shear function to be expressed when synthesizing with other members. That is, the fastening bolts 402 and 412 express a function of fixing the H-beam steel 400 and the T-beam steel 410 to the upper formwork 100 and, at the same time, function as a shear key after dismantling.

In addition, a plurality of incision holes 102 are formed in the upper formwork 100 at regular intervals along the bottom surface of the space portion where the flanges 401 and 411 of the H-beam steel 400 and the T-beam steel 410 come into contact with each other. Correspondingly, in the flanges 401 and 411 of the H-beam 400 and the T-beam 410, the horizontal shear reinforcement 403 is exposed to the outside through the incision hole 102 at the portion facing the incision hole 102. , 413) may be protrudingly coupled.

Although the horizontal shear reinforcing bars 403 and 413 are illustrated as having a “c” shape in FIG. 3 , the present invention is not limited thereto, and any shape is provided as long as the structure can have a horizontal shear function when combined with other members. is also free

As such, the H-beam 400 and the T-beam 410 can be manufactured from the steel composite square beam 1 shown in FIG. 3 through the curing process of the concrete poured into the pouring space 11, and in particular, the H-beam 400 ) and horizontal shear reinforcing bars 403 and 413 protrude from the respective flanges 401 and 411 of the T-shaped steel 410, so that it is possible to achieve synthesis with other members such as the upper slab.

Next, in the pouring space 11, the end plate 120 is inserted up to the section set in each H-beam steel 400, and the tension bar 131 is located in the center at a position spaced apart from each H-beam steel 400. After disposing the formed fixing plate 130, a step of connecting and fixing a plurality of strands or a plurality of steel rods 140 between both fixing plates 130 along the longitudinal direction of the pouring space 11 (step S20) is performed.

In order to implement the step S20, the centrifugal rotation formwork 10 has the same plate structure as the cross-section of the pouring space 11 and the first through-hole 121 cut in the same way as the cross-section of the H-beam steel 400 ) is formed and further includes a pair of end closure plates 120 inserted and disposed from the pouring space 11 to the set section of each H-shaped steel 400 .

The end plate 120 performs a function as a magnet plate to close the end of the prismatic beam 1, and in particular, as it is inserted up to the set section of the H-beam 400, the H-beam at both ends of the prismatic beam 1 ( By exposing one section of 400 , it can be manufactured to provide a connection part 420 for connection with a neighboring column.

In addition, as shown in FIG. 9 , it is preferable that the anti-slip border 123 formed with an outward inclination gradient is formed on the edge of the end closure plate 120 as an elastic material. That is, as shown in the drawing, the anti-slip rim 123 is attached to the edge of the end closure plate 120 in a form in which an inclination gradient (α) having a larger diameter is formed at the side end of the end closure plate 120 .

It is appropriate to use an elastic material such as rubber for the anti-slip border 123 .

Based on the shape of the anti-slip rim 123, the end closure plate 120 is easy to mount and can be securely mounted, and controls the end closure plate 120 from being pushed outward in the rotation process and tension process. will be able to do In particular, when eccentricity acts on the end closure plate 120 during the rotation process, the smoothness of the end is not maintained as well as the application of prestress to the stranded wire is not easy. It is to control that the distortion is applied to the plate (120). In addition, the anti-slip border 123 is configured to reduce noise caused by friction between the end closure plate 120 and the centrifugal rotation mold 10 during centrifugal rotation.

In addition, the centrifugal rotating formwork 10 has the same plate structure as the cross section of the pouring space 11 and a pair of fixing plates disposed at a position spaced apart from the end of each H-shaped steel 400 in the pouring space 11 . (130).

As the fixing plate 130 is disposed in the pouring space 11 in a plate shape corresponding to the hexagonal cross section of the pouring space 11 , sliding flow is possible in the longitudinal direction of the pouring space 11 .

And the fixing plate 130 is configured with a tension bar 131 exposed to the outside of the sealing plate 20 through the sealing plate 20 in the central portion of the outer surface, the longitudinal direction of the pouring space 11 Both ends of a plurality of strands or a plurality of steel rods 140 that are spaced apart from each other in parallel along and pass through the second through-holes 122 formed in each end plate 120 are on a pair of fixing plates 130. it will be fixed

That is, the tension bar 131 of the fixing plate 130 is exposed to the sealing plate 20 coupled to the opening 12 on one side and the other side of the centrifugal rotation die 10, respectively, and the tension bar 131 is It may have a bolt structure, and the fixing plate 130 flows outward in the pouring space 11 by clockwise rotation by fastening the nut in the sealing plate 20, so that a pair of fixing plates 130 Since the tensile force is applied to the plurality of strands or the plurality of steel bars 140 connected between them in a batch or stepwise manner, prestress may be introduced during the manufacturing process of the prismatic beam 1 .

Next, a sealing plate ( 20), the step of sealing the inlet by combining the opening and closing plate after input of concrete through the inlet formed in the lower formwork 110 (step S30), and penetrating the sealing plate 20 and exposing to the outside It has a step (step S40) of tensioning the tension bar 131 so that prestress is introduced to the plurality of strands or the plurality of steel bars 140 in batches or steps by the flow of the fixing plate 130 in the pouring space (step S40).

The sealing plate 20 is respectively coupled to the openings 12 provided on one side and the other side of the centrifugal rotation die 10 to seal the pouring space 11 .

For example, the sealing plate 20 may be fastened or separated through bolt coupling with flanges formed along both openings 12 of the centrifugal rotation die 10, and a hollow is formed in the center of the fixing plate ( The tension bar 131 of 130) penetrates from the pouring space 11 to be exposed to the outside.

The lower formwork 110 has at least one inlet 111 provided at regular intervals along the longitudinal direction of the centrifugal rotation die 10 so as to communicate with the space portion as shown in FIG. 5B, and the inlet 111 includes It includes an opening and closing plate 112 coupled to each inlet 111 to open and close.

The centrifugal rotating formwork 10 may inject concrete through the inlet 111 provided in the lower formwork 110 in a state in which the upper formwork 100 and the lower formwork 110 are coupled to each other, and the concrete input After completion, the opening and closing plate 112 may be bolted to the inlet 111 to seal the exposed inlet 111 .

Meanwhile, in the square beam 1 manufactured by the above-described centrifugal molding apparatus and a manufacturing method using the same, the hollow portion 2 is formed by centrifugal molding. It is desirable to manufacture so that it can be limited to at least 10% or less.

Accordingly, as in the conventional PHC pile manufacturing process, since it is not possible to secure a hollow ratio of 10% or less by pouring empty-mixed concrete into the formwork, as described above, a separate concrete input inlet ( 111) and increasing the amount of pouring by increasing the slump of non-solidified concrete, it is possible to maintain the hollow ratio of the entire cross-section of the prismatic beam 1 to 10% or less.

In addition, as mentioned above, the concrete uses ultra-high-strength (100 MPa or more) concrete to secure the strength of the prismatic beam (1), and the prestress is applied to efficiently resist the load and long-term deflection applied from the long-span structure. It is preferable to introduce a bar, and in the centrifugal forming apparatus, a plurality of strands or a plurality of steel rods 140 for prestress introduction are mounted while a tensile force can be applied to a plurality of strands or a plurality of steel rods 140 in batches or steps. It may have a fixed structure.

Next, by rotating the centrifugal rotation die 10, centrifugal molding is performed (step S50) so that the hollow part 2 is formed in the center of the square beam 1 (step S50).

For this purpose, the rotating means 30 must be configured, and the rotating means 30 rotates the centrifugal rotating mold 10 in a selected direction to be put into the pouring space 11 of the centrifugal rotating mold 10 and filled. Centrifugal molding of ultra-high strength concrete.

As an example, the rotating means 30 includes a base structure 300 installed at a position spaced apart from the lower portion of the centrifugal rotation form 10 , and an outer periphery thereof while being supported by the base structure 300 , the centrifugal rotation It is closely attached to the outer periphery of the mold 10 and includes a pair of rotating rollers 310 that are not shown, but rotate the centrifugal rotating mold 10 by applying a rotational force from a driving motor.

The pair of rotating rollers 310 are installed in at least two places along the longitudinal direction of the centrifugal rotating formwork 10 in consideration of the length and area of the centrifugal rotating formwork 10, thereby stabilizing the centrifugal rotating formwork (10). rotational drive.

Next, steam-drying the centrifugal rotary formwork 10 on which the centrifugal molding is completed to cure the centrifugally-formed prismatic beam 1 (step S60), and the upper mold 100 of the centrifugal rotary formwork 10 and Separating the lower formwork 110 will have a step (step S70) of demolding and transferring the centrifugally formed square beam 1 from the pouring space 11 .

Hereinafter, the manufacturing method of the present invention will be described once again with reference to FIGS. 8A to 8F.

In the manufacturing method of the present invention, the prismatic beam 1 is manufactured using the above-described centrifugal forming apparatus. Although not shown in the drawings, the upper formwork 100 and the lower formwork 110 constituting the centrifugal rotary formwork 10 are ), the upper formwork 100 is rotated 180 degrees for seating and coupling of the unit section steel member 40 so that the space portion of the upper formwork 100 faces upward.

In addition, a plurality of unit section steel members 40 are placed and combined in the space of the upper formwork 100 and the unit section steel members 40 are synthesized by pouring ultra-high-strength concrete. It is preferable to apply a release agent to the space so that the contact surface of the prismatic beam 1 manufactured in the process can be easily peeled off.

Thereafter, as shown in Fig. 8a, each H-beam steel 400 is disposed as one of the unit section steel members 40 on one side and the other side of the upper formwork 100, and a plurality of T-beam steels ( 410) are arranged at regular intervals.

A plurality of fastening holes 101 and cut-out holes 102 are formed in the upper formwork 100 , and when the H-shaped steel 400 and the T-shaped steel 410 are placed, the upper formwork 100 is moved to the outside. The fastening bolts 402 and 412 of the H-beam steel 400 and the T-beam steel 410 are exposed, and the H-beam steel 400 and the T-beam steel 410 are connected by fastening the nuts to each of the exposed fastening bolts 402 and 412. Fix it.

Next, as shown in FIG. 8b, the end closing plate 120 is inserted up to the section set in each H-beam steel 400 placed therein, and the fixing plate 130 is disposed at a position spaced apart from each H-beam steel 400. After that, a plurality of strands or a plurality of steel rods 140 are connected and fixed between both fixing plates 130 along the longitudinal direction of the pouring space 11 .

Thereafter, the lower mold 110 is coupled to the upper mold 100 and the sealing plate 20 so that the tension bars 131 of the fixing plate 130 pass through the open ends of the centrifugal rotation mold 10 . and, as shown in FIG. 8D, ultra-high-strength concrete is put in through the inlet 111 formed in the lower formwork 110, and the opening and closing plate 112 is coupled to seal the inlet 111.

And as shown in FIG. 8e, by screwing the nut 132 to the tension bar 131 exposed to the outside through the sealing plate 20 and rotating it clockwise to tension between the fixing plates 130 on both sides. , the flow of each fixing plate in the pouring space 11 and a plurality of strands or a plurality of steel rods 140 connected thereto are collectively or step-by-step prestressed to be introduced.

Although not shown in the drawings, in a state in which pre-stress is introduced, the rotating means 30 connected to the centrifugal rotating formwork 10 is operated to rotate the centrifugal rotating formwork 10 so that the hollow part 2 is formed ( 1) is centrifugally molded, and the centrifugal rotary mold (1), which has been centrifuged, is steam-dried to cure the centrifugally molded prismatic beam (1).

At this time, in the centrifugal molding process by the rotating means 30, it is preferable to sequentially advance the rotational speed of the driving motor from low to medium speed again from medium to high speed.

Finally, as shown in FIG. 8f, after moving the centrifugal rotating formwork 10 that has undergone the steam drying process, a bolt connecting the upper formwork 100 and the lower formwork 110 and the unit section steel member 40 After separating the nuts fastened to the fastening bolts 402 and 412 of The process of transferring the gakhyeongbo (1) is performed.

As shown in FIG. 3 , in the rectangular beam 1 manufactured by the manufacturing method of the present invention, a prestress by a stranded wire or a plurality of steel rods 140 is introduced while the hollow part 2 is formed, and the upper surface of the prismatic beam 1 is formed. A plurality of horizontal shear reinforcing bars 403 and 413 are exposed at regular intervals along the longitudinal direction, and a connecting portion 420 exposing some sections of the embedded unit section member 40, respectively, may be provided at both ends.

As described above, the square beam 1 manufactured by the manufacturing method of the present invention is excellent in quality as it is manufactured in a factory using the above-described centrifugal molding device, and has excellent durability due to high watertightness due to centrifugal molding manufacturing, and ultra-high strength concrete ( 100 MPa or more), it has the advantage of securing the strength with a non-cracked structure by introducing pre-stress, enabling a low form and height, and easy to secure the building limit of the structure.

In addition, as the unit section steel member 40 for connection with members such as adjacent columns or upper slab is embedded and synthesized inside, only the horizontal shear reinforcing bars 403 and 413 are exposed to minimize painting. It is inexpensive and has the advantage of improving productivity.

Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims are also provided. is within the scope of the

1: square beam 2: hollow part
10: centrifugal rotating formwork 11: pouring space
12: opening 20: sealing plate
30: rotation means 100: upper mold
101: fastening hole 102: incision hole
110: lower mold 111: inlet
112: opening and closing plate 120: end end plate
121: through hole 130: fixing plate
131: tensile bar 140: stranded wire or steel bar
400: H-beam 410: T-beam

Claims (4)

In the method of manufacturing a prismatic beam using a centrifugal forming apparatus comprising a centrifugal rotating die divided into two in parallel along the longitudinal direction and comprising an upper and lower formwork that are coupled and separated from each other and having a pouring space formed therein,
Placing H-beams on one side and the other side of the upper formwork, respectively, and disposing and fixing a plurality of T-beams at regular intervals between both H-beams (step S10);
In the pouring space, the end finishing plate is inserted up to the section set for each H-beam, and a fixing plate with a tension bar is disposed in the center at a position spaced apart from each H-beam, and then a plurality of strands or a plurality of strands along the longitudinal direction of the pouring space connecting and fixing the steel bars between both fixing plates (step S20);
The lower formwork is mutually coupled to the upper formwork, and the sealing plate is connected so that the tension bars of the fixation plate pass through the open ends of the centrifugal rotating formwork, and the opening and closing plate is combined after the concrete is put through the inlet formed in the lower formwork. sealing the inlet (step S30);
Tensing the tensile bar exposed to the outside through the sealing plate so that prestress is introduced to the plurality of strands or the plurality of steel rods in batches or steps by the flow of the fixing plate in the pouring space (step S40);
Centrifugally molding the centrifugal rotating mold to form a hollow in the center of the prismatic beam (step S50);
Curing the centrifugally molded prismatic beam by steam-drying the centrifugal rotary mold on which the centrifugal molding is completed (step S60); and
Separating the upper and lower molds of the centrifugal rotating formwork to demold and transfer the centrifugally-formed prismatic beam from the pouring space (step S70); including;
In the step S10, in the upper formwork, a plurality of fastening holes are formed through the bottom surface of the space portion in contact with the flanges of the H-beam and T-beams, and the flanges of the H-beams and T-beams have fastening holes in the portion facing the fastening holes. A fastening bolt exposed to the outside is formed through the
In the step S70, a method of manufacturing an ultra-high strength prismatic beam using a centrifugal forming apparatus, characterized in that the fastening bolts are exposed to the outside of the flanges of H-beams and T-beams when the upper formwork is dismantled.
delete The method of claim 1,
In the step S10, the upper formwork has a plurality of cut-out holes formed at regular intervals along the bottom surface of the space where the flanges of the H-beam and T-beams are in contact, and the flanges of the H- and T-beams have a portion facing the cutouts. A method of manufacturing an ultra-high-strength prismatic beam using a centrifugal molding device, characterized in that horizontal shear reinforcement exposed to the outside through the incision hole is coupled.
The method of claim 1,
In the step S20, a method of manufacturing an ultra-high-strength prismatic beam using a centrifugal molding apparatus, characterized in that the edge of the end-closing plate is formed of an elastic material and an anti-slip rim formed with a slope to the outside.

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