KR20160087217A - Precast concrete structure with monolithic beam-column connection and location adjustable plastic hinge - Google Patents

Abstract

The present invention relates to a precast concrete (PC) structure forming a precast concrete member with a column and a beam and, more specifically, relates to a PC structure, which secures monolithic ability of a PC column and a PC beam, and induces generation of a plastic hinge in an end portion of the PC beam. According to an appropriate embodiment of the present invention, a precast concrete (PC) structure with a monolithic beam-column connection portion and a location adjustable plastic hinge comprises: a PC hollow column; a PC lattice beam; an upper PC hollow column; and a PC central beam.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a PC structure capable of adjusting an integral joint and a plastic hinge position,

More particularly, the present invention relates to a PC structure for securing the integrity of a PC column and a PC beam and for inducing generation of a plastic hinge at a PC beam edge, and more particularly to a PC structure for constructing a column and a beam using precast concrete members .

In general, the Precast Method (hereinafter referred to as PC method) is a method in which a structure member of a building is prefabricated in advance with a precast concrete (hereinafter referred to as "PC") member, In a predetermined position.

The PC method is used to solve the shortage of labor force at the construction site or to reduce the cost by reducing the use of the construction material. By using the dry method that installs the factory PC PCs on site, Materials and so on.

The PC structure is composed of columns that are vertical structure members and beams that are horizontal structural members, and PC members that are manufactured in the factory. They are combined as a unit member to form a frame to form a building. As described above, in the case of the PC method, since the PC member manufactured in the factory is used, the quality of the member is improved as compared with the member manufactured by the cast-in-place method, and the placement of the wet concrete is minimized, It can be applied to a limited number of advantages. This is because the joining structure of the column and the beam which are most important in the PC method, especially the joining structure in which the column and the beam are integrated into one, and the stability is secured, are not sufficiently secured. In other words, the horizontal member should transmit the load to the column, which is a vertical member, and the column and the column must be combined very firmly. In order to form a solid structure, the column and the beam must be integrated. However, in the conventional joint structure, the reinforcing bars buried in the PC beams are broken and connected to the PC columns, and the columns and beams are bonded to the joints so that the concrete is laid on the joints. As a result, the stability is not sufficiently ensured, The PC method is limited.

Particularly, PC method is applied to the field of logistics warehouse and parking lot. Because of the characteristics of PC method, which is performed by prefabricated structure, seismic performance is problematic. PC structure which receives lateral load such as seismic load, Most of the deformation is concentrated at the end of the beam, and the brittle behavior is observed in which the column and the joint are damaged. In the case of earthquakes, damage to the columns and joints causes damage to the load path, resulting in sudden collapse of the whole structure, resulting in loss of lives, which limits the introduction of the PC method in residential buildings with seismic performance problems .

As a background of the present invention, there is a patent registration No. 10-1078795 entitled 'Formwork for connection of precast concrete column and beam and construction method using the same' (Patent Document 1). This patent is made up of four unit members as a form of a PC-type column and a PC-type beam, and each of the unit members has a side wall formed in a bent state so as to partially contact two side surfaces adjacent to the concrete body in the PC- A wing portion formed to protrude on the outer side surface of the side wall portion and formed to extend in the same plane as a side surface and a bottom surface portion of the concrete member in the PC type beam and a fastening means for fastening the adjacent unit members to each other, The present invention proposes a form for forming a beam-formwork-opening by mutual coupling with a wing portion of an adjacent unit member and a construction method using the same. Since the mold proposed by this patent is constructed by assembling a plurality of unit members in a simple manner, it is possible to easily install the form on the junction of the PC type column and the beam, thereby saving time and manpower required for formwork installation and reusing the unit However, most of the deformation is concentrated at the end of the beam at the PC column-beam joint receiving the lateral load, which may cause damage to the column and the joint.

Patent Registration No. 10-1078795 'Formwork for connection of precast concrete column and beam and construction method using the same'

SUMMARY OF THE INVENTION It is an object of the present invention to provide a PC structure having a joining structure for ensuring the integrity of a PC column and a PC beam.

Another problem of the present invention is to prevent damage of the column-to-beam connection due to the fact that the deformation is not concentrated on the end of the beam joined to the column when the lateral load is generated, and the kinetic energy due to the earthquake is dissipated by the plastic deformation when the earthquake load is generated to prevent the sudden collapse So as to provide a PC structure with sufficient ductility behavior.

Another object of the present invention is to provide a PC structure capable of adjusting the position of the plastic hinge formed on the beam.

The monolithic joint and the PC structure capable of adjusting the plastic hinge position according to a preferred embodiment of the present invention include a concrete portion having a cavity formed therein, a plurality of cast iron rods embedded in the longitudinal direction of the concrete portion, A lower PC hollow column consisting of a bar reinforced with concrete at intervals; A hollow communicating with the hollow of the lower PC hollow column is formed at the central portion and is formed into a cross shape crosswise at the center portion and is embedded so that the U-shaped hook reinforcement protrudes at each end, PC grid beam installed; A concrete portion having a hollow communicating with the hollow of the PC grid beam, a plurality of cast iron rods buried in the longitudinal direction in the concrete portion, and a bar steel bar embedded in the concrete portion at regular intervals along the longitudinal direction so as to surround the cast iron rods Upper PC hollow column installed on top of PC grid beam; And a PC central beam installed between the PC grating beams so as to protrude at both ends of the U-shaped hook reinforcement. The cavity of the lower PC hollow column, the PC grid beam, and the upper PC hollow column is filled with the spotted concrete, The PC hollow column, the PC grid beam and the upper PC hollow column are integrally joined, and the lower PC hollow column and the upper PC hollow column are connected to each other at the outside of the PC grid beam.

In this case, the cast iron core of the lower PC hollow column is configured to protrude to the upper surface of the lower PC hollow column, and the cast iron root of the upper PC hollow column is protruded to the lower surface of the upper PC hollow column. The cast iron roots of the cast iron and upper PC hollow columns can be connected by a coupler.

Alternatively, the cast iron core of the lower PC hollow column may protrude from the upper surface of the lower PC hollow column, and the lower PC hollow column may have a sleeve embedded therein, so that the protruded cast iron rope of the lower PC hollow column, Lt; / RTI >

The monolithic joint and the PC structure capable of adjusting the plastic hinge position according to a preferred embodiment of the present invention include a concrete portion having a cavity formed therein, a plurality of cast iron rods embedded in the longitudinal direction of the concrete portion, A lower PC hollow column consisting of a bar reinforced with concrete at intervals; A hollow communicating with the hollow of the lower PC hollow column is formed at the central portion and is formed into a cross shape crosswise at the center portion and is embedded so that the U-shaped hook reinforcement protrudes at each end, PC grid beam installed; A concrete portion having a hollow communicating with the hollow of the PC grid beam, a plurality of cast iron rods buried in the longitudinal direction in the concrete portion, and a bar steel bar embedded in the concrete portion at regular intervals along the longitudinal direction so as to surround the cast iron rods Upper PC hollow column installed on top of PC grid beam; And a PC central beam installed between the PC grating beams so as to protrude at both ends of the U-shaped hook reinforcement. The cavity of the lower PC hollow column, the PC grid beam, and the upper PC hollow column is filled with the spotted concrete, The PC hollow column, the PC grid beam and the upper PC hollow column are integrally joined, and the lower PC hollow column and the upper PC hollow column are configured to penetrate the PC grid beam.

In this case, the cast iron core of the lower PC hollow column is configured to protrude from the upper surface of the lower PC hollow column, and the sleeve is buried in the lower end of the upper PC hollow column so that the projected cast iron root of the lower PC hollow column penetrates the PC grid beam, Can be connected in sleeve of PC hollow column.

In the meantime, in the central portion of the PC grid beam, a cast steel reinforcing bar is embedded so as to protrude to the upper and lower sides, and a sleeve is embedded in the upper end of the lower PC hollow column and the upper end of the lower PC hollow column, The connecting bars may be connected at the sleeve of the upper PC hollow column and the sleeve of the lower PC hollow column.

According to the present invention, hollows communicating with the lower PC hollow column, the PC grid beam, and the upper PC hollow column are respectively formed and filled with the spotted concrete in the hollow, the upper and lower columns and the ball are integrally joined, The cast iron rods of the PC hollow column are configured to be connected to each other, so that the integrity of the column-to-beam joint structure is secured, thereby improving the stability of the structure as a whole.

Particularly, according to the present invention, since the plastic hinge is induced in the PC grid beam, which is the means for constructing the end of the beam joined to the column in the column and beam structure, and the connecting portion of the PC center beam, which is the means constituting the central part of the beam, It is possible to economically design the hinge to adjust the position of the structure so that the structure has a smaller strength than the intensity requirement of the elastic state and to induce the collapse mechanism of the structure to be the most secure due to the occurrence of the plastic hinge when the earthquake load occurs, It is possible to prevent the brittle fracture of the brittle material.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments of the invention and, together with the description, serve to explain the principles of the invention, Shall not be construed as limiting.
1 is an exploded perspective view of an integral joint and a PC structure capable of adjusting a plastic hinge position according to the present invention, and FIG.
FIG. 3A is an exploded perspective view of an integral joint and a PC structure capable of adjusting a plastic hinge position according to an embodiment of the present invention, and FIG.
FIG. 4A is an exploded perspective view of a PC structure capable of adjusting a plastic hinge position and an integral joint according to another embodiment of the present invention, and FIG.
FIG. 5A is an exploded perspective view of a PC structure capable of adjusting a plastic hinge position and an integral joint according to still another embodiment of the present invention, and FIG.
6 is a schematic diagram for explaining the structural behavior of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in the accompanying drawings, but the present invention is not limited thereto.

1 is an exploded perspective view of an integral joint and a PC structure capable of adjusting a plastic hinge position according to the present invention, and FIG.

The PC structure according to the present invention comprises a lower PC hollow column 10, a PC grid beam 20, an upper PC hollow column 30, and a PC center beam 40.

The lower PC hollow column 10 is made of PC-length material and includes a concrete portion 12 having a hollow 11 formed therein, a plurality of cast iron rods 13 embedded in the longitudinal direction of the concrete portion 12, And a reinforcing bar 14 embedded in the concrete part 12 so as to surround the concrete part 12 at regular intervals along the longitudinal direction.

The PC grid beam 20 is provided on the upper surface of the lower PC hollow column 10 and has a hollow portion 21 formed in the middle portion 22 communicating with the hollow 11 of the lower PC hollow column 10, Shaped hook reinforcement 23 protruding in a cross shape about the center of the U-shaped hook reinforcement 22, and the U-shaped hook reinforcement 23 is embedded at each end.

An upper PC hollow column 30 is provided on the upper part of the PC grid beam center, and the upper PC hollow column 30 is the same as the lower PC hollow column 10.

The PC grid beam 20 is a means for providing an end structure of a beam joined to a column in a structure made up of columns and beams and providing a joining structure for integrally connecting the upper and lower columns. In order to secure the integrity of the joint structure, hollows 11, 21 and 31 communicating with each other are formed in the lower PC hollow column 10, the PC grid beam 20 and the upper PC hollow column 30, The hollow is filled with the cast concrete (50), and the upper and lower pillars and the beam are integrally joined. In order to ensure the integrity of the joint structure, the lower PC hollow column 10 of the present invention and the cast iron rods 13 and 33 of the upper PC hollow column 30 are connected to each other. The connecting method of the cast iron rods (13, 33) can be performed by various methods, which will be described later.

The PC center beam 40 is installed between the PC grid beams 20 and is embedded at both ends so that the U-shaped hook reinforcement 41 protrudes. The PC central beam 40 is a means constituting a central portion of the beam in a structure composed of a column and a beam. When the PC center beam 40 is installed at the end of the PC grid beam 20, the U-shaped hook reinforcement 41 of the end of the PC center beam 40 and the U-shaped hook reinforcement of the end of the PC grid beam 20 23 are installed so as to overlap with each other, and then the cast concrete 50 is laid in one piece. The processes such as the installation of the cast concrete 50 and the installation of reinforcing bars or molds for curing, etc., The method of Fig. The stiffness and strength of the spotted concrete 50 are determined by calculation of the structure so as to be smaller than the stiffness and strength of the PC central beam 40 or the PC grid beam 20 to induce the plastic hinge. The plastic hinge and its structural behavior will be described later.

FIG. 3A is an exploded perspective view of an integral joint and a PC structure capable of adjusting a plastic hinge position according to an embodiment of the present invention, and FIG.

As described above, the bottom PC hollow column 10 of the present invention and the cast iron rods 13 and 33 of the upper PC hollow column 30 are configured to be connected to each other for ensuring the integrity of the column- The width of the column is smaller than or equal to the width of the column section.

In the present embodiment, the width of the beam is smaller than the width of the columnar section, so that the lower PC hollow column 10 and the cast iron rods 13 and 33 of the upper PC hollow column 30 are located outside the PC grid beam 20 Respectively. 3, the PC grid beam 20 is inserted between the cast iron rods 13 of the lower PC hollow column 10 and the protruding end of the cast iron rods 13 of the lower PC hollow column 10 is inserted into the upper PC hollow column 10, (30). To this end, the cast iron core 13 of the lower PC hollow column 10 is configured to protrude from the upper surface of the lower PC hollow column 10 and the sleeve 35 is embedded at the lower end of the upper PC hollow column 30, The projected cast iron rods of the lower PC hollow column 10 are connected at the sleeve 35 of the upper PC hollow column. The sleeve 35 may be any member commonly used in the PC process and the sleeve 35 should be pre-buried at the time of fabrication of the upper PC hollow column 30. In order to fill the filling material into the sleeve 35, the upper PC hollow column concrete portion 32 should be pre-drilled with the filling hole 32h as shown in the figure.

Although not shown, the cast iron core 13 of the lower PC hollow column 10 and the cast iron 33 of the upper PC hollow column 30 are connected to the upper surface of the lower PC hollow column 10 and the upper PC hollow column 30, respectively. And may be connected to a coupler at the outside of the PC grid beam 20, and the coupler may be selected from any material known in the art.

FIG. 4A is an exploded perspective view of a PC structure capable of adjusting a plastic hinge position and an integral joint according to another embodiment of the present invention, and FIG.

In the present embodiment, the width of the beam is equal to or larger than the width of the column section. As shown in Fig. 4, the cast iron core 13 of the lower PC hollow column 10 is divided into the lower PC hollow column 10 And a sleeve 35 is embedded in the lower end of the upper PC hollow column 30 so that the protruded cast iron 13 of the lower PC hollow column 10 is projected onto the upper surface of the PC grid beam 20, Through the sleeve (35) of the upper PC hollow column (30). For this purpose, the PC grid beam 20 must be previously drilled through holes at positions corresponding to the cast iron rods 13 of the lower PC hollow column 10.

FIG. 5A is an exploded perspective view of a PC structure capable of adjusting a plastic hinge position and an integral joint according to still another embodiment of the present invention, and FIG.

In the present embodiment, the cast steel reinforcing bars 24 are embedded in the central portion 22 of the PC grid beam 20 so as to protrude to the upper and lower sides of the PC grid beam 20, So that the protruded cast iron reinforcing bars 24 of the PC grid beam 20 are inserted into the sleeve 35 of the upper PC hollow column and the sleeve 15 of the lower PC hollow column, Lt; / RTI >

6 is a schematic diagram for explaining the structural behavior of the present invention.

The mechanical behavior of the monolithic joint portion and the PC structure capable of adjusting the plastic hinge position according to the present invention constructed as described above will be described with reference to FIG.

Typical methods that can withstand earthquakes are to increase the stiffness of the structure and to dissipate the kinetic energy of the earthquake by plastic deformation even after the structure reaches the yielding state to give sufficient ductility to prevent sudden collapse There is a way.

The method of increasing the stiffness of the structure is designed to have a high strength so that the yield of the structure does not occur with respect to the expected earthquake, which is uneconomical. Unless an innovative material that exceeds concrete is developed, it is impossible to secure absolute stability because of the problem of economic efficiency.

Therefore, the seismic design criteria used in each country are designed to have the strength less than the strength requirement of the elastic state considering the inelastic behavior of the structure, and indirectly considering the energy dissipation capacity of the structure that may occur in the inelastic region with respect to the seismic load Which has been introduced in the past.

Plastic design (plastic design) is the ultimate limit state of a structure. It is a method to directly investigate plastic collapse and to design rationality against stability. This is a design method against elastic permissible stress design method, A sufficient number of plastic hinges are formed in the frame to calculate the load when the frame reaches the collapse mechanism, and the safety is compared with the external force.

Plastic moment hinge means that when the load is increased beyond the elastic limit of the material in the beam subjected to bending, it enters the bending area from the outermost edge of the beam and finally the entire section of the beam enters the bending area. That is, one of the neutral axes is plastic-pressed and the other is subjected to a plastic tension. In this state, keep the constant bending moment constantly, and continue the shafts (rotation axis) like a hinge. The mechanical state of the section in this state is referred to as a plastic hinge. That is, even if one member in the structure reaches the sintering state, the structure is not collapsed, and other members that fail to reach the fracture stress state bear the overload.

Since earthquakes are not likely to occur frequently during the lifetime of a structure, unlike natural disasters such as floods and drought, partial damage is recognized in order to promote economic efficiency under social agreements. Structural damage is minimized, To induce the plastic hinge so that the safest collapse mechanism occurs.

According to the present invention, in connecting the PC grid beam 20 constituting the end portion of the beam joined to the column to the PC center beam 40 constituting the central portion of the beam, The concrete pavement 50 having the stiffness and strength smaller than the stiffness and strength of the beam 40 and the PC grid beam 20 is constructed so that the connection between the PC grid beam 20 and the PC center beam 40 And acts as a plastic hinge. It is possible to freely adjust the position of the PC grid beam 20 and the PC center beam 40 by adjusting the length of the PC grid beam 20 and the PC center beam 40 in inducing the plastic hinge.

As described above, according to the present invention, hollows communicating with the lower PC hollow column, the PC grid beam, and the upper PC hollow column are respectively formed, and the hollow columns are filled with the spotted concrete, and the upper and lower columns and the ball are integrally formed. The columns and the cast iron rods of the upper PC hollow column are configured to be connected to each other to ensure the integrity of the column-to-beam joint structure.

In addition, since the plastic hinge is induced in the PC grid beam, which is the means for constructing the end portion of the beam joined to the column, and the connecting portion of the PC central beam, which is the means constituting the central portion of the beam, It is possible to design economically to have a smaller strength and to induce plastic hinge to occur when a seismic load is generated so that the safest collapse mechanism can be structurally generated.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the above teachings. will be. The invention is not limited by these variations and modifications, but is limited only by the claims appended hereto.

10: Lower PC hollow column 11: Lower PC hollow column hollow
12: Lower PC hollow column Concrete part 13: Lower PC hollow column Cast iron rods
14: Lower PC hollow column strap 15: Lower PC hollow column sleeve
20: PC grid beam 21: PC grid beam hollow
22: PC grid center part 23: PC grid beam U-shaped hook reinforcement
24: Reinforcing steel bars 30: Top PC hollow columns
31: Top PC hollow column hollow
32: Top PC hollow column concrete part 32h: Filled hole
33: Top PC Hollow Column Cast Iron Curve 34: Top PC Hollow Column Tie Rein
35: Top PC hollow column sleeve 40: PC center beam
41: central beam U-shaped hook reinforcing bar 50: spot cast concrete

Claims (6)

A plurality of reinforcing bars 13 embedded in the longitudinal direction of the concrete portion 12 and a plurality of concrete portions 12 formed at predetermined intervals along the longitudinal direction so as to surround the reinforcing bars 13, A lower PC hollow column 10 made up of a band reinforcing bar 14 embedded in the lower reinforcing bar 12;
A hollow 21 communicating with the hollow 11 of the lower PC hollow column 10 is formed in the central portion 22 and has a shape crosswise crossing around the central portion 22. The U- A PC grid beam (20) embedded in the bottom of the lower PC hollow column (10) so that the hook reinforcement (23) protrudes therefrom;
A concrete portion 32 in which a hollow 31 communicating with the hollow 21 of the PC grid beam 20 is formed, a plurality of cast iron rods 33 embedded in the longitudinal direction of the concrete portion 32, a cast iron 33, An upper PC hollow column 30 formed on the upper surface of the PC grid beam 20 and composed of a reinforcing bar 34 which is embedded in the concrete part 32 at a predetermined interval along the longitudinal direction so as to surround the PC grid beam 20; And
And a PC center beam (40) installed between the PC grid beams (20) so that U - shaped hook reinforcements (41) protrude from both ends thereof.
21 and 31 of the PC grid beam 10 and the PC grid beam 20 and the upper PC hollow column 30 are filled with the spotted concrete 50 so that the lower PC hollow column 10 and PC The lattice beam 20 and the upper PC hollow column 30 are integrally joined,
Wherein the lower PC hollow column 10 and the upper PC hollow column 30 are connected to each other at the outside of the PC grid beam 20. The integrated joint and the plastic hinge position can be adjusted PC structure. The method according to claim 1,
The cast iron rope 13 of the lower PC hollow column 10 is configured to protrude from the upper surface of the lower PC hollow column 10,
The cast iron core 33 of the upper PC hollow column 30 is configured to protrude to the lower surface of the upper PC hollow column 30,
Wherein the main reinforcing bars (13) of the lower PC hollow columns and the reinforcing bars (33) of the upper PC hollow columns are connected to each other by a coupler from the outside of the PC grid beam (20), and the PC structure capable of adjusting the plastic hinge positions. The method according to claim 1,
The cast iron rope 13 of the lower PC hollow column 10 is configured to protrude from the upper surface of the lower PC hollow column 10,
A sleeve (35) is embedded in the lower end of the upper PC hollow column (30)
Characterized in that the projected cast iron rods of the lower PC hollow column (10) are connected at the sleeves (35) of the upper PC hollow column, and the PC structure capable of adjusting the plastic hinge position. A plurality of reinforcing bars 13 embedded in the longitudinal direction of the concrete portion 12 and a plurality of concrete portions 12 formed at predetermined intervals along the longitudinal direction so as to surround the reinforcing bars 13, A lower PC hollow column 10 made up of a band reinforcing bar 14 embedded in the lower reinforcing bar 12;
A hollow 21 communicating with the hollow 11 of the lower PC hollow column 10 is formed in the central portion 22 and has a shape crosswise crossing around the central portion 22. The U- A PC grid beam (20) embedded in the bottom of the lower PC hollow column (10) so that the hook reinforcement (23) protrudes therefrom;
A concrete portion 32 in which a hollow 31 communicating with the hollow 21 of the PC grid beam 20 is formed, a plurality of cast iron rods 33 embedded in the longitudinal direction of the concrete portion 32, a cast iron 33, An upper PC hollow column 30 formed on the upper surface of the PC grid beam 20 and composed of a reinforcing bar 34 which is embedded in the concrete part 32 at a predetermined interval along the longitudinal direction so as to surround the PC grid beam 20; And
And a PC center beam (40) installed between the PC grid beams (20) so that U - shaped hook reinforcements (41) protrude from both ends thereof.
21 and 31 of the PC grid beam 10 and the PC grid beam 20 and the upper PC hollow column 30 are filled with the spotted concrete 50 so that the lower PC hollow column 10 and PC The lattice beam 20 and the upper PC hollow column 30 are integrally joined,
Wherein the lower PC hollow column and the upper PC hollow column are connected to the PC grid beam so that the PC grid beam can pass through the PC grid beam and the PC structure capable of adjusting the plastic hinge position. . 5. The method of claim 4,
The cast iron rope 13 of the lower PC hollow column 10 is configured to protrude from the upper surface of the lower PC hollow column 10,
A sleeve (35) is embedded in the lower end of the upper PC hollow column (30)
Characterized in that the protruded cast iron rope (13) of the lower PC hollow column (10) is connected to the sleeve (35) of the upper PC hollow column (30) through the PC grid beam (20) Adjustable PC structure. 5. The method of claim 4,
The reinforcing bars 24 are embedded in the center portion 22 of the PC grid beam 20 so as to protrude upward and downward.
Sleeves 35 and 15 are respectively embedded in the lower end of the upper PC hollow column 30 and the upper end of the lower PC hollow column 10,
Wherein the protruded cast iron reinforcing bars 24 of the PC grid beam 20 are connected at the sleeve 35 of the upper PC hollow column and at the sleeve 15 of the lower PC hollow column. This possible PC structure.

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