KR102505916B1 - Placing apparatus of pumpability improved concrete and placing method using thereof - Google Patents

Abstract

A concrete casting device with improved pumpability is disclosed. The concrete pouring device with improved pumpability according to the present invention is for continuous casting by discharging concrete with improved pumpability through a nozzle while moving in a construction area where rebars are continuously placed, and a steel pipe for supply connected to a concrete supply unit, a supply unit including a flexible flexible pipe coupled to an end of the steel pipe for supply; a steel pipe for a nozzle having one end connected to an end of the flexible pipe and having a nozzle at the other end; and a housing having a pouring space blocked from the outside on all sides except for a lower part, and having a nozzle coupling part for coupling the steel pipe for the nozzle to the front so that the nozzle is located in the pouring space, and the concrete supply unit It is characterized in that the concrete that is pressurized from the supply unit is discharged only to the pouring space of the housing through the nozzle to lower the discharge noise during concrete discharge and block the leakage of concrete particles and dust to the outside.

Description

Concrete pouring device with improved pumpability and concrete pouring method using the same

The present invention relates to a concrete pouring device with improved pumpability and a method for pouring concrete using the same, and more particularly, to improve fluidity and secure pumpability by incorporating air bubbles and natural fibers into concrete that is difficult to pump. Form concrete with improved pumpability, and after easily pumping the concrete with improved pumpability using a concrete pump, spray it with high-pressure air of 3 atmospheres or more to dissipate excess air contained in the concrete and produce a large amount of water. Not only can the slump increased due to air bubbles be reduced to the slump range of the original concrete, but also the noise and dust generated when the concrete is sprayed with air pressure of 3 atmospheres or more can be removed. Concrete pouring with improved pumpability. It relates to a device and a concrete pouring method using the device.

Depending on the construction method and construction conditions, concrete is produced in a batcher plant, transported to the site, and then subjected to very large vibrations or piezoelectric to compact the concrete to make the inside dense.

For example, highway concrete is constructed by applying vibration of 8,500 RPM or more to concrete with a slump (slump - thinness or softness) of 20 mm to 40 mm, and dam concrete has a very large cross-section, so to minimize the accumulation of heat of hydration that can occur It is common to produce concrete by minimizing the amount of unit cement and compacting it with a roller. Even when constructing a sloped structure, it must be constructed with concrete to prevent spillage.

Light rail is defined as a means of transportation between existing buses and railroads with a transport capacity of 5,000 to 30,000 per hour, and has advantages such as constructability, economic feasibility, and ease of maintenance, so construction is increasing recently.

The light rail system uses rubber wheels as driving wheels, and is suitable for downtown routes or low-depth railroads because of its excellent response to steep gradients and sharp curves.

It is essential to pour concrete to prevent the concrete from flowing down during construction due to the Kent and slope caused by the steep slope or steep curve on the track on which the rubber wheels of the light train travel.

However, since the construction of the rubber wheel driveway is constructed at the last stage after the auxiliary structures are built, in the case of a narrow and long section on the ground or a narrow and long underground tunnel, concrete cannot be transported by ready-mixed concrete trucks and concrete is covered over a distance of several hundred meters. Send and build. It is very difficult to pour concrete by pumping it with a concrete pump.

In particular, the cross-slope of the rubber wheel track is steep, with the maximum cross-slope of the left and right tracks being 6%. Therefore, when constructing a running path on a steep curve, as shown in FIG. 1, surface deformation continuously occurs until a predetermined adhesive force and strength resisting the gravitational direction are expressed. This deformation of the running road causes a deformation of the flatness of the running road in the longitudinal section and a deformation of the amount of cross slope in the crossing section. Therefore, the liquidity must be high for concrete long-distance conveying, and the conflicting requirements of concrete for ramp construction must be satisfied.

In other words, although the specification stipulates slump concrete of 80mm for high-quality concrete construction and ramp construction, concrete material separation, bleeding, and cracking occur by using concrete with a slump of 230 - 250mm in order to pressurize concrete approximately 500-600m. However, very serious problems occurred such as loss of strength, decrease in durability, deterioration of quality, and occurrence of run-down. In particular, there was a problem that it was impossible to construct a slope of 6% with concrete with a slump of 230-250mm.

The pumpability of concrete required to pump concrete to the construction area is defined as the stability and mobility of concrete under the pressure inside the closed pipe. Stability means a state without material separation that causes clogging, and mobility is It is expressed as the pipe flow of concrete. Therefore, in order to secure the pumpability of concrete, it is necessary to maintain appropriate viscosity and secure high fluidity.

As such, as a prior art for placing concrete in a place with a large cross slope, Korean Patent Registration No. 10-1789159 (published date: 2017.10.23) discloses a method for constructing a sloped upper surface of high fluidity concrete using divisional continuous pouring with temporary partitions. This is disclosed. In this method of constructing the inclined upper surface, the flow of the poured concrete in the inclined direction in each compartment space was suppressed, and thus the inclined upper surface of the finished concrete could be maintained in each compartment space. There was a problem in that workability was deteriorated by having to install a partition wall for forming the.

On the other hand, as another prior art, Republic of Korea Patent Registration No. 10-1692017 (published date: 2017.01.03) discloses a fiber-reinforced concrete manufacturing apparatus and manufacturing method through shorting after mixing air bubbles in ordinary concrete. The fiber-reinforced concrete manufacturing device was able to reduce the slump when the fiber-mixed concrete was sprayed by high-pressure air, thereby securing construction workability, but noise and dust when the fiber-mixed concrete was sprayed by high-pressure air. There was a problem with this.

. Republic of Korea Patent Registration No. 10-1789159 (Announcement date: 2017.10.23) . Republic of Korea Patent No. 10-1692017 (Announcement date: 2017.01.03)

An object of the present invention is to improve the pumpability of the concrete so that it can be placed after pumping, and during placement, the slump can be maintained within the normal range, and noise and dust generated when concrete is sprayed with high-pressure air and placed It is to provide a means to prevent it.

In addition, the problem to be solved by the present invention is not limited to the above-mentioned technical problems, and other technical problems not mentioned above will be clear to those skilled in the art from the description below. You will be able to understand.

The above object, according to the present invention, is to discharge and pour concrete with improved pumpability through a nozzle while moving in a construction area where reinforcing bars are continuously placed, and to continuously pour a steel pipe for supply connected to a concrete supply unit, and the steel pipe for supply Supply unit including a flexible flexible pipe coupled to the end; a steel pipe for a nozzle having one end connected to an end of the flexible pipe and having a nozzle at the other end; and a housing having a pouring space blocked from the outside on all sides except for a lower part, and having a nozzle coupling part for coupling the steel pipe for the nozzle to the front so that the nozzle is located in the pouring space, and the concrete supply unit Concrete with improved pumpability, characterized in that the concrete pumped from the supply unit is discharged only to the pouring space of the housing through the nozzle, thereby reducing the discharge noise during concrete discharge and blocking the external leakage of concrete particles and dust. This is achieved by means of a casting device.

In the construction area, a rolling support means for supporting the flexible pipe by rolling is provided, and the rolling support means includes: a support plate installed on an upper surface of the reinforcing bar to prevent interference with the reinforcing bar when the flexible tube moves; and a movable body disposed on the upper surface of the support plate with moving wheels provided on a lower surface and a seating groove formed on an upper surface for seating a part of the flexible tube, wherein the flexible tube is seated on the movable body. When pulling and moving, the flexible tube can be moved without interference on the upper surface of the support plate by the moving wheels of the moving body.

A connector for connecting to the enclosure may be provided on the support plate in contact with the enclosure, and each support plate may be configured to be detachably connected to each other by a connection means.

The enclosure is provided with a transparent window for visually checking the inside of the pouring space, a filter member for discharging air discharged through the nozzle, and an inner side of the pouring space in contact with the concrete discharged through the nozzle. A noise reduction member may be provided at the top.

At the lower end of the enclosure, a skirt for blocking concrete particles and dust generated in the pouring space from leaking to the outside may be detachably provided.

The nozzle coupling part may include a front installation hole and an upper surface installation hole formed so that a portion of the front vertical wall and a portion of the upper plate of the enclosure are cut and connected to each other; A lower coupling member provided on the front vertical wall so as to correspond to the front installation hole by forming a lower fitting end concavely formed in a semicircular shape for fitting while surrounding a portion of the coupling groove formed in the steel pipe for the nozzle; And an upper fitting end symmetrical to the lower fitting end is formed in a lower region and has a lower support part for covering the front installation hole, and an upper support part extending horizontally from the lower support part and covering the upper surface installation hole, In a state in which a part of the steel pipe for the nozzle is fitted into the lower fitting end, the upper fitting end may be inserted into the coupling groove to include a fixing member coupled to the enclosure to fix the steel pipe for the nozzle. .

The fixing member moves downward along the guide groove provided at the upper end of the front of the enclosure so that the upper fitting end is inserted into the coupling groove or moved upward and separated, and is selectively coupled to the enclosure by a fastening member. can be configured.

The nozzle coupling part is opened downward at the lower end of the front vertical wall of the enclosure, and the upper fitting end is concavely formed in a semicircular shape so as to be coupled while surrounding a part of the coupling groove formed in the steel pipe for the nozzle; and a lower fitting end having a shape symmetrical to that of the upper fitting end so that the upper part of the fitting part is wrapped around and coupled to the lower part of the fitting groove in a state in which the upper part of the fitting part is wrapped and coupled to the upper part of the fitting part. It may be configured to include a lower coupling member coupled to the lower end of the vertical wall.

The above object is, according to the present invention, a method of pouring concrete using a concrete pouring device with improved pumpability, comprising: a concrete forming step of forming concrete by mixing water, cement, and aggregate; Injecting air bubbles and natural fibers into the concrete to increase the slump of the concrete; A concrete manufacturing step with improved pumpability in which air bubbles and natural fibers are added to the concrete and then mixed to prepare concrete with improved pumpability and fluidity; And by spraying the concrete with improved pumpability with high-pressure air through a nozzle installed inside the enclosure of the concrete casting device to dissipate the bubbles contained in the concrete with improved pumpability, the increased pumpability due to the bubbles is improved It is achieved by a concrete pouring method using a concrete pouring device with improved pumpability, comprising a spray step of reducing the slump of concrete to the slump range of the original concrete.

The spraying step may include a housing installation step of installing the housing of the concrete casting device in a construction area where concrete is to be poured; A support plate installation step of installing support plates on top of the reinforced reinforcing bars and connecting the support plate to the enclosure; A nozzle installation step of coupling a nozzle of a steel pipe for a nozzle connected to a flexible pipe to a nozzle coupling part provided in the enclosure; a flexible tube rolling support step of disposing each moving body having wheels for movement on the support plate and supporting the flexible tube by rolling the flexible tube by seating the flexible tube in a seating groove of the moving body; and a continuous concrete pouring step of continuously pouring concrete with improved pumpability while moving the support plate and the housing while spraying concrete with improved pumpability with the nozzle and placing the concrete on the reinforced reinforcing bars.

According to the present invention, by improving the pumpability by introducing air bubbles and natural fibers into the concrete to increase the slump, it is possible to smoothly convey the concrete to a narrow and long construction area where ready-mixed concrete cannot enter, and the conveyed concrete can be conveyed through a nozzle. By spraying with compressed air, air bubbles can be dissipated to provide the effect of reducing the slump of concrete.

In addition, it is possible to increase the slump during the pumping of concrete and reduce the slump during the pouring, so that the construction of pouring concrete in a narrow and long section where ready-mixed concrete cannot enter or an inclined cross section of a narrow and long tunnel can be performed easily and smoothly. possible effects can be provided.

In addition, since the nozzle through which the concrete is sprayed is located in the pouring space provided in the enclosure of the concrete pouring device, noise generated during concrete pouring can be prevented or significantly reduced, as well as dust and concrete particles generated during spraying. It is possible to provide the effect of not leaking to the outside.

In addition, a flexible flexible pipe is provided between the concrete supply unit and the nozzle, a support plate is installed in the construction area, and a movable body for rolling the flexible pipe is provided on the upper surface of the support plate, so that the flexible pipe is formed with a wire wrench (claw) It is possible to provide an effect in which the nozzle can be easily moved because movement and bending are smooth without interference with the reinforcing bars during work such as pulling.

1 is a schematic diagram for explaining the surface deformation of concrete constructed in the conventional slope section.
Figure 2 is an exploded perspective view showing a concrete casting device with improved pumpability according to a preferred embodiment of the present invention.
3 is an exploded perspective view showing a rolling support means for rolling the flexible pipe shown in FIG. 2;
Figure 4 is a schematic cross-sectional view showing a concrete casting device with improved pumpability shown in Figures 2 and 3.
FIG. 5 is a schematic enlarged cross-sectional view for explaining a state in which a skirt is provided on a vertical wall of the enclosure shown in FIG. 2 .
Figure 6 is a schematic plan view for explaining the action of the concrete casting device with improved pumpability shown in Figure 4.
7 is a partially enlarged cross-sectional view showing another embodiment of the nozzle coupling part shown in FIG. 2 .
8 is a comparison table showing slump changes before and after spraying of concrete with improved pumpability according to the present invention.
Figure 9 is a graph for explaining the change of the sludge pump according to the input of air bubbles and natural fibers according to the present invention to the concrete.
Figure 10 is a graph for explaining the change in the amount of air remaining after spraying the concrete with improved pumpability according to the present invention into which air bubbles and natural fibers are introduced.
11 is a draft for explaining the crack reduction effect during spray construction of concrete with improved pumpability according to the present invention into which air bubbles and natural fibers are introduced.
12 is a draft for explaining the viscosity change of concrete during spray construction of concrete with improved pumpability according to the present invention into which air bubbles and natural fibers are introduced.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, in describing the present invention, descriptions of already known functions or configurations will be omitted to clarify the gist of the present invention.

In this specification, the terms used are for describing the embodiments and are not intended to limit the present invention. In this specification, singular forms also include plural forms unless specifically stated otherwise in a phrase. The terms 'comprises' and/or 'comprising' used in the specification do not exclude the presence or addition of one or more other elements.

In this specification, when an element is referred to as being “connected” to another element, it should be understood that although it may be directly connected to the other element, other elements may exist in the middle. On the other hand, when an element is referred to as being “directly connected” to another element, it should be understood that no intervening elements exist.

In this specification, the terms used are only used to describe specific embodiments, and are not intended to limit the present invention.

In this specification, singular expressions include plural expressions unless the context clearly dictates otherwise.

Among the accompanying drawings, Figure 2 is an exploded perspective view showing a concrete pouring device with improved pumpability according to a preferred embodiment of the present invention, Figure 3 is a rolling support means for supporting the flexible pipe shown in Figure 2 It is an exploded perspective view shown, and FIG. 4 is a schematic cross-sectional view showing a concrete casting device with improved pumpability shown in FIGS. 2 and 3.

As shown in FIGS. 2 and 4, the concrete casting device 10 with improved pumpability according to the present invention has improved pumpability while moving in the construction area (A) in which the reinforcing bars (I) are continuously arranged. It is for continuous casting by discharging to the nozzle 32 provided at the end of the steel pipe 22 for supply, and the concrete that is pressurized from the concrete supply unit (not shown) to the supply unit 20 passes through the nozzle 32 to the enclosure ( 40) to be discharged only into the pouring space (S), thereby lowering the discharge noise during concrete discharge and blocking the leakage of concrete particles and dust to the outside.

This concrete casting device 10 includes a supply unit 20 including a supply steel pipe 22 connected to the concrete supply unit and a flexible flexible pipe 24 coupled to an end of the supply steel pipe 22, and the flexible pipe A steel pipe 30 for a nozzle having one end connected to the end of 24 and having a nozzle 32 at the other end, and a pouring space S blocked from the outside on all sides except for the lower part are formed, and the nozzle 32 is at the front. ) It is configured to include a housing 40 provided with a nozzle coupling part 42 for coupling the steel pipe 30 for a nozzle so that a part of the pouring space is located in the pouring space (S).

This will be described in more detail.

The supply unit 20 is characterized in that a flexible flexible pipe 24 is provided between the supply steel pipe 22 and the nozzle steel pipe 30 connected to the concrete supply unit. The flexible pipe 24 is for changing the position of the nozzle 32 in a state where the position of the steel pipe 22 for supply is fixed, and as shown in FIG. 6, it is made of a corrugated pipe made of a freely bendable material.

Such a flexible pipe 24 is supported by a rolling support means 50 installed on the upper surface of the reinforced reinforcing bars I in the construction area A. That is, as shown in FIGS. 3 and 6 , the rolling support means 50 for rolling the flexible pipe 24 is provided in the construction area A. The rolling support means 50 includes at least one support plate 52 installed on the upper surface of the reinforcing bar (I) to prevent interference with the reinforcing bar (I) when the flexible pipe 24 moves, and wheels for movement on the lower surface. (54A) are provided and a seating groove (54B) for seating a part of the flexible pipe (24) is formed on the upper surface, and it consists of a moving body (54) disposed on the upper surface of the support plate (52). By this rolling support means 50, in a state where the flexible pipe 24 is seated in the seating groove 54B of the moving body 54, the flexible pipe 24 can be moved by pulling it with a wire wrench (hook - not shown). When the moving body 54 is rolled on the upper surface of the support plate 52 by the moving wheels 54A, the flexible pipe 24 can move smoothly.

On the other hand, each support plate 52 is installed flat on the upper surface of the reinforcing bar (I) so that the flexible pipe 24 is smoothly bent or moved without interfering with the reinforced reinforcing bar (I), each support plate 52 ) Can be installed and removed independently of each other, but in this embodiment, each support plate 52 is detachably connected to each other, and the support plate 52 in contact with the enclosure 40 is configured to be connected to the enclosure 40 described as a basis.

Each support plate 52 may be detachably connected to each other by means of a connecting means. As an example of the connection means, as shown in FIGS. 3 and 6, it will consist of connection holes 52A formed in the support plate 52 and connection pins 52B penetrating each connection hole 52A. can In this way, both support plates 52 can be connected to each other by passing through the connecting holes 52A on both sides where the connecting pins 52B match each other. In this embodiment, each support plate 52 is described based on being connected by a connecting pin 52B, but is not limited thereto, and although not shown in the drawing, it is possible to separate from each other by a hinge, a connecting ring and a connecting ring, a connecting piece, etc. can be connected In addition, handles for attaching by a worker or holding a wire wrench (hook) may be provided on the support plate 52 and the moving body 54, respectively. Using these handles, the support plates 52 connected to each other can be pulled and moved in a forward direction, and the moving body 54 can be moved.

On the other hand, the support plate 52 in contact with the enclosure 40 is provided with a connecting body 56 to be connected to the enclosure 40. The connecting body 56 is composed of a horizontal end and a vertical end, and the horizontal end is fixed to the support plate 52, and the vertical end is fixedly coupled to the fastening holes provided on both sides of the front surface of the enclosure 40, thereby connecting the support plate 52 and The enclosure 40 may be connected and integrated.

As described above, when the support plate 52 and the enclosure 40 are connected, the support plate 52 and the enclosure 40 are integrally moved as the support plate 52 is pulled forward or the enclosure 40 is moved forward. It is movable, and therefore, it is possible to continuously pour concrete by spraying concrete with the nozzle 32 in the pouring space S while simultaneously moving the enclosure 40 and the support plate 52.

The steel pipe 30 for a nozzle is provided with a nozzle 32 and is intended to be connected to the flexible pipe 24, and is connected to the flexible pipe 24 by a clamp or the like at one end. And the nozzle 32 is connected to a compressed air supply pipe so that compressed air for spraying is supplied. A coupling groove 34 is formed in an annular shape around the outer circumferential surface of the steel pipe 30 for the nozzle. The coupling groove 34 is to be firmly coupled to the nozzle coupling portion 42 of the housing 40, and a part of the lower coupling member 42A is fitted into the lower region of the coupling groove 34, and the upper region A portion of the fixing member 42B is fitted. Due to this structure, only the nozzle 32 is positioned in the pouring space S of the housing 40.

The housing 40 is to block the space where the concrete is poured from the outside so that particles, dust, and noise generated during spraying of the concrete sprayed from the nozzle 32 do not leak to the outside. In this housing 40, a pouring space (S) blocked from the outside is formed on all sides except for the lower part, and the nozzle 32 is positioned in the pouring space (S) at the front so that the nozzle steel pipe 30 is coupled. A nozzle coupling part 42 is provided.

As shown in FIGS. 2 and 3, the enclosure 40 has a rectangular rectangular enclosure shape by the frame body 41, but is not limited thereto, and the pouring space S opened downward therein If the structure is formed, it is satisfied.

A nozzle coupling part 42 is provided in front of the enclosure 40 . The nozzle coupling part 42 has a front installation hole 42C-1 and an upper surface installation hole 42C-2 so that a part of the front vertical wall 43 and a part of the upper plate 45 of the enclosure 40 are cut and connected to each other. are formed respectively. The lower fitting end 42A-1 for fitting while surrounding a part of the coupling groove 34 formed in the steel pipe 30 for the nozzle is formed concave in a semicircular shape to correspond to the front installation hole 42C-1. A coupling member (42A) is provided on the front vertical wall (43). An upper fitting end 42B-1 symmetrical to the lower fitting end 42A-1 is formed in the lower area and a lower support part 42B-2 for covering the front installation hole 42C-2, and a lower support part 42B. It extends horizontally from -2) and has an upper support part (42B-3) for covering the upper surface installation hole (42C-2), and a part of the steel pipe 30 for the nozzle is fitted into the lower fitting end (42A-1). In the state in which the upper fitting end (42B-1) is inserted into the upper region of the coupling groove 34 includes a fixing member (42B) coupled to the housing 40 to fix the steel pipe 30 for the nozzle. The fixing member 42B is detachably coupled to the upper end of the enclosure 40 by a fastening bolt or the like. Then, the fixing member (42B) is guided to the guide groove 47 provided at the front upper end of the enclosure 40, and moves in the upper and lower vertical directions. Therefore, when the fixing member 42B is moved downward in a state where the lower fitting end 42A-1 is fitted in the lower portion of the coupling groove 34, the lower support portion 42B-2 of the fixing member 42B guides the guide groove 47 ), so that the upper fitting end (42B-1) can be accurately inserted into the coupling groove (34).

In this way, the fixing member 42B is coupled to the enclosure 40 so that the lower part of the steel pipe 30 for the nozzle is fitted with the lower fitting end 42A-1 and the upper part is fitted with the upper inclined end 42B-1. As a result, the steel pipe 30 for the nozzle maintains a solid and stable coupling state to the housing 40, and the nozzle 32 is located in the pouring space S, and the front installation hole 42C-1 and the upper surface installation hole (42C-2) may be covered.

Among the accompanying drawings, FIG. 7 shows another embodiment of the nozzle coupling unit.

As shown in FIG. 7, the nozzle coupling part 42 according to another embodiment is opened downward at the lower end of the front vertical wall 43 of the enclosure 40, and the coupling groove 34 formed in the steel pipe 30 for the nozzle ) The upper fitting coupling end 43A formed concavely in a semicircular shape so as to be coupled while wrapping a portion of the coupling groove 34 in a state where the upper region of the coupling groove 34 is wrapped around and coupled to the upper fitting coupling end 43A A lower coupling member 48 coupled to the lower end of the front vertical wall 43 with a bolt or the like having a lower fitting coupling end 48A having a shape symmetrical to the upper fitting coupling end 43A so as to be coupled while wrapping the lower region of the ) ) is composed of. As described above, since the nozzle coupling part 42 according to another embodiment is configured to open downward, it is not necessary to form the front installation hole 42C-1 and the upper surface installation hole 42C-2 in the housing 40.

Although not shown in the drawing, the above-mentioned nozzle coupling part 42 forms a fastening hole in the enclosure 40 and forms a screw on the outer circumferential surface of the steel pipe 30 for a nozzle to form a steel pipe 30 and the enclosure 40 for a nozzle. may be coupled with a screw fastening structure.

On the other hand, transparent windows 44 are provided on the front, rear, side and upper surfaces of the enclosure 140 to visually check the inside of the pouring space S, and filter the air discharged through the nozzle 32 to the outside. A filter member 46 for discharging is provided. The transparent window 44 may be made of a transparent acrylic material, a urethane pad, or the like. These transparent windows 44 may be provided in several places or only in part. In addition, the filter member 46 is preferably disposed in the opposite direction to the nozzle coupling part 42, that is, toward the rear side.

On the other hand, as shown in Figures 2 and 3, the noise reduction member 49 is provided on the inner upper part of the pouring space (S) in contact with the concrete discharged through the nozzle 32. The noise reduction member 49 may be made of a urethane pad, or may be made of a plate material of various materials that performs a buffering function while maintaining strength.

And, at the lower end of the enclosure 40, a skirt 70 is detachable to block concrete particles and dust generated in the pouring space S from leaking to the outside through the enclosure 40 and the reinforcing bars I. made possible The skirt 90 may be made of a fabric material, a urethane material, a silicone material, a rubber material, or the like. The skirt 70 may be fixed by a coupling piece in a state in which the upper end is in close contact with the lower end of the frame body 41 of the housing body 40. The coupling pieces are fixed to the frame body 41 with screws, bolts, or the like. Since the skirt 70 is made of a flexible soft material, it is possible to cover a space between the lower portion of the housing 40 and the reinforcing bars I or between the lower portion of the housing 40 and the floor.

The method of pouring concrete with improved pumpability in the narrow and long construction area (A) or the narrow and long tunnel construction area (A) using the concrete casting device 10 with improved pumpability configured as described above is as follows. same.

(a) concrete formation step

The concrete forming step is a step for forming concrete, which is formed by mixing water, cement, and aggregate. The slump of the concrete made at this time is approximately 80 - 100mm.

(b) Step of inserting foam and natural fibers

The step of introducing air bubbles and natural fibers is a step for increasing the slump of the concrete made at the construction site, and increases the slump of the concrete made by adding air bubbles (cellulosic) and natural fibers to the ready-mixed concrete moved to the construction site. That is, air bubbles and natural fibers are added and mixed before the concrete is pumped, and the slump value of the concrete, which is approximately 80 - 100 mm, is increased to 200 - 250 mm to improve fluidity.

The effect of air bubbles and natural fibers on the slump of concrete was found through the following experiment.

1. Target properties of the experiment

. Target slump: 220±10 mm before spraying, 100±10 mm after spraying

. Target air volume: within 6% after spraying

2. Formulation

. Specified mixing (1㎥)

division W/B
(%) S/a
(%) Unit Weight (kg/m ³ ) W C P/A GBFS S G WRA nature
fiber combination 38 48.8 160 295 63 63 845 893 3.58 One

. W/B: water binding material ratio . S/a: Fine aggregate ratio . W: Water. C: Cement

. F/A: Fly ash. GBFS : blast furnace slag powder . S: sand. G: gravel

. WRA: water reducing agent

3. Experiment

a. Natural fiber not mixed - Cellular mixing test

. Mixing ready-mixed concrete -> Remixing after mixing 180L of air bubbles -> Spray

b. Experiments with mixing natural fibers and air bubbles (180L)

. Mixing ready-mixed concrete -> Remixing after adding 180L of air bubbles and natural fibers -> Spray

c. Mixing of natural fibers - bubble (240L) mixing test

. Mixing ready-mixed concrete -> Remixing after adding air bubbles (240L) and natural fibers -> Spray

4. Experimental results

a. Slump change and final air volume

division Slump (mm) Air volume (%) significant No air bubbles added
(Remicon) Adding air bubbles
(before spraying) after spray after spray No mixing of natural fibers
Add bubble 180L 130 225 130 4.5

× Blend of natural fibers
Add bubble 180L 160 210 85
4.5 Blend of natural fibers
Add bubble 240L 150 230 100

As confirmed in Table 1.2, it can be seen that when natural fibers are not added to the concrete, the slump value returns to the same value as the original concrete. In addition, it can be seen that the slump value decreases when natural fibers are added, and it can be seen that the slump value can vary according to the amount of air bubbles added. And it can be seen that the amount of air after spraying is constant.

b. Change in slump before and after spraying

As shown in FIGS. 8 and 9 among the accompanying drawings, it was confirmed that the slump before and after spraying of the concrete mixed with air bubbles and natural fibers was clearly different. That is, it can be seen that the slump of the concrete in which only 180L of air bubbles were injected was 225 mm, improving the fluidity, and lowering to 130 mm after spraying. In addition, the slump of concrete with 180L of air bubbles and natural fibers is improved to 210mm, but after spraying, the slump is reduced to 85mm. It was found that it decreased to 100 mm.

In other words, by adding air bubbles and natural fibers to concrete, the slump increases significantly, and after spraying, a low slump of less than 150 mm can be secured, so that the fluidity of the concrete can be secured and pumpability can be improved. You can secure the slump required by the area.

c. Final air volume after spraying

Experimental results As shown in FIG. 10, regardless of the amount of air added, the final air amount was 4.5%, which is a very good level. These figures satisfy the range of 4-6% air volume suggested by Korea Expressway Corporation to secure durability, and large bubbles of the remaining air are all dissipated and only small bubbles form 4%, so it has a very positive effect on durability. Able to know.

d. Crack reduction effect when natural fibers are mixed into concrete

As a result of spraying after mixing and mixing natural fibers into the concrete, it was found that the crack reduction effect was clearly expressed.

That is, as shown in FIG. 11, it was found that there is a 40-60% crack reduction effect (difference by fiber length) when 1 kg/m 3 of natural fiber is incorporated. At this time, it was found that the crack reduction effect increased as the mixing amount of natural fibers increased.

e. Viscous change of concrete when natural fibers are mixed into the concrete

As shown in FIG. 12 of the accompanying drawings, it can be seen that when natural fibers (kenaf) are added (mixed) to concrete, the viscosity increases and decreases compared to normal concrete (OPC). In addition, it was found that the viscosity of concrete increased as the length of natural fibers increased and the mixing amount increased.

(b) spray step

In the spray step, air bubbles and natural fibers are injected into the ready-mixed concrete at the construction site to prepare concrete with improved pumpability, and the concrete with improved pumpability manufactured in this process is placed inside the enclosure 40 of the concrete casting device 10. This is a step of spraying with high-pressure air through the nozzle 32 installed on the That is, by spraying and pouring concrete with improved pumpability, bubbles contained in the concrete are dissipated, and the slump of the concrete with improved pumpability due to the bubbles is reduced to the slump range of the original concrete. This is a step of continuous pouring construction. .

This will be described in more detail.

Before spraying and pouring the concrete with improved pumpability with the nozzle 32, the enclosure installation step of installing the enclosure 40 of the concrete casting device 10 in the construction area A where the concrete is to be poured proceeds. At this time, the width of the enclosure 40 and the width of both sides of the construction area (A) in which the reinforcing bars (I) are placed coincide. That is, the enclosure 40 is disposed so that all areas in which the reinforcing bars I are placed in the pouring space S of the enclosure 40 are covered. To this end, it is preferable to manufacture the enclosure 40 in consideration of the width of the construction area (A).

Subsequently, the support plate installation step of installing the support plates 52 on top of the reinforcing bars I in the construction area A and connecting the housing 40 and the support plate 52 with the connection body 56 proceeds. Then, each support plate 52 is also connected to each other, but connected to match the length of the flexible pipe 24 so that the movement of the flexible pipe 24 is made smoothly without interference.

When the support plates 52 are installed in the above process, the nozzle installation step of coupling the nozzle 32 of the steel pipe 30 for the nozzle connected to the flexible pipe 24 to the nozzle coupling part 42 provided in the enclosure 40 proceed with

When the nozzle 32 is coupled to the nozzle coupling part 42, each moving body 54 having moving wheels 54A is disposed on the upper surface of the support plates 52, and the seating groove 54B of each moving body 54 The flexible pipe rolling support step of supporting the flexible pipe 24 by seating the flexible pipe 24 in the rolling is performed. At this time, the flexible pipe 24 seated in the seating groove 54B may be fixed to the moving body 54 using a band or clamp. This is to prevent the flexible pipe 24 from being separated from the seating groove 54B while pulling the flexible pipe 24 with a wire wrench.

Subsequently, the concrete with improved pumpability is sprayed with the nozzle 32 to place the concrete on the reinforced reinforcing bars (I). Then, while moving the support plate 52 and the enclosure 40 to the space where the concrete is to be poured, a continuous concrete pouring step of continuously pouring the concrete with improved pumpability is performed.

As described above, when the concrete casting is completed in the set construction area (A) by connecting the supporting plates 52 and the housing 40, the supporting plates 52 and the housing 40 are moved forward by a predetermined distance to perform concrete pouring. Construction proceeds continuously. During the continuous pouring of concrete, the flexible pipe 24 is supported by the moving body 54 on the support plate 52, so the flexible pipe 24 can be operated smoothly.

In particular, since the nozzle 32 sprays the concrete from the inside of the enclosure 40, fine concrete particles and dust generated when the concrete is sprayed by high-pressure air do not leak out of the pouring space S, so that the concrete is pleasant. It is possible to provide a pouring construction site, and since the spraying of concrete is performed only in the pouring space (S), noise generated by spraying can be minimized or prevented.

In the foregoing, although specific embodiments of the present invention have been described and shown, the present invention is not limited to the described embodiments, and it is common knowledge in the art that various modifications and variations can be made without departing from the spirit and scope of the present invention. It is self-evident to those who have Therefore, such modifications or variations should not be individually understood from the technical spirit or viewpoint of the present invention, and modified embodiments should fall within the scope of the claims of the present invention.

10: concrete casting device 20: supply unit
30: steel pipe for nozzle 32: nozzle
40: enclosure 42: nozzle coupling part
44: transparent window 46: filter member
49: noise reduction member 50: rolling support means
52: support plate 54: moving body
A: Construction area I: Rebar

Claims (10)

It is for continuous pouring by discharging concrete with improved pumpability through a nozzle while moving in the construction area where reinforcing bars are continuously placed.
A supply unit including a steel pipe for supply connected to the concrete supply unit and a flexible flexible pipe coupled to an end of the steel pipe for supply;
a steel pipe for a nozzle having one end connected to an end of the flexible pipe and having a nozzle at the other end; and
A pouring space blocked from the outside is formed on all sides except for the lower part, and a housing is provided with a nozzle coupling part for coupling the steel pipe for the nozzle so that the nozzle is located in the pouring space,
The concrete that is pressurized from the concrete supply unit to the supply unit is discharged only to the pouring space of the enclosure through the nozzle to reduce the discharge noise generated during concrete discharge and block external leakage of concrete particles and dust,
The vessel is
A transparent window for checking the inside of the pouring space with the naked eye is provided, a filter member is provided for discharging air discharged through the nozzle, and a noise reduction is provided on the inner upper part of the pouring space where the concrete discharged through the nozzle comes in contact. Characterized in that the member is provided,
A concrete pouring device with improved pumpability. According to claim 1,
In the construction area,
A rolling support means for supporting the flexible pipe by rolling is provided, and the rolling support means includes: a support plate installed on an upper surface of the reinforcing bar to prevent interference with the reinforcing bar when the flexible tube moves; and
A mobile body disposed on the upper surface of the support plate with wheels for movement provided on the lower surface and a seating groove formed on the upper surface for seating a part of the flexible pipe,
Characterized in that the flexible tube is moved without interference on the upper surface of the support plate by the moving wheels of the moving body when the flexible tube is pulled and moved in a state where the flexible tube is seated on the moving body.
A concrete pouring device with improved pumpability. According to claim 2,
Characterized in that the support plate in contact with the enclosure is provided with a connecting body to be connected to the enclosure, and each of the support plates is detachably connected to each other by a connecting means,
A concrete pouring device with improved pumpability. delete According to claim 1,
At the bottom of the enclosure,
Characterized in that a skirt for blocking concrete particles and dust generated in the pouring space from leaking to the outside is detachably provided,
A concrete pouring device with improved pumpability. According to claim 1,
The nozzle coupling part,
A front installation hole and an upper surface installation hole formed so that a part of the front vertical wall and a part of the top plate of the enclosure are cut and connected to each other;
A lower coupling member provided on the front vertical wall so as to correspond to the front installation hole by forming a lower fitting end concavely formed in a semicircular shape for fitting while surrounding a portion of the coupling groove formed in the steel pipe for the nozzle; and
An upper fitting end symmetrical to the lower fitting end is formed in a lower region and includes a lower support part for covering the front installation hole, and an upper support part extending horizontally from the lower support part and covering the upper surface installation hole, Characterized in that the upper fitting end includes a fixing member coupled to the enclosure to be inserted into the coupling groove to fix the steel pipe for the nozzle.
A concrete pouring device with improved pumpability. According to claim 6,
The fixing member is
Characterized in that the upper fitting end is guided to a guide groove provided at the upper front end of the enclosure so as to be inserted into the coupling groove, and is selectively coupled to the enclosure by a fastening member.
A concrete pouring device with improved pumpability. According to claim 1,
The nozzle coupling part,
an upper fitting end formed concavely in a semicircular shape so as to be coupled while surrounding a portion of the coupling groove formed in the steel pipe for the nozzle by opening downward at the lower end of the front vertical wall of the enclosure; and
In a state where the upper region of the coupling groove is wrapped around and coupled to the upper fitting coupling end, a lower fitting coupling end having a shape symmetrical to the upper fitting coupling end is provided so that the lower region of the coupling groove is coupled while being wrapped around the front vertical wall. Characterized in that it comprises a lower coupling member coupled to the lower end of,
A concrete pouring device with improved pumpability. A method of pouring concrete using the concrete casting device with improved pumpability according to any one of claims 1 to 3 and 5 to 8,
A concrete forming step of forming concrete by mixing water, cement, and aggregate;
Injecting air bubbles and natural fibers into the concrete to increase the slump of the concrete;
A concrete manufacturing step with improved pumpability in which air bubbles and natural fibers are added to the concrete and then mixed to prepare concrete with improved pumpability and fluidity; and
The concrete with improved pumpability is sprayed with high-pressure air through a nozzle installed inside the enclosure of the concrete casting device to dissipate the air bubbles contained in the concrete with improved pumpability, thereby reducing the increased slump due to the bubbles to the original concrete Characterized in that it comprises a spray step of reducing to the slump range of
A concrete pouring method using a concrete pouring device with improved pumpability. According to claim 9,
The spray step is
An enclosure installation step of installing the enclosure of the concrete casting device in a construction area where concrete is to be poured;
A support plate installation step of installing support plates on top of the reinforced reinforcing bars and connecting the support plate to the enclosure;
A nozzle installation step of coupling a nozzle of a steel pipe for a nozzle connected to a flexible pipe to a nozzle coupling part provided in the enclosure;
a flexible tube rolling support step of disposing each moving body having wheels for movement on the support plate and supporting the flexible tube by rolling the flexible tube by seating the flexible tube in a seating groove of the moving body; and
A continuous concrete pouring step of continuously pouring concrete with improved pumpability while moving the support plate and the housing while spraying concrete with improved pumpability with the nozzle and placing concrete on the reinforced reinforcing bars Characterized in that,
A concrete pouring method using a concrete pouring device with improved pumpability.

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