JP7201173B2 - Wet curing method for concrete - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for efficiently wet-curing concrete after demolding when constructing underground structures such as tunnels, culverts, and underpasses.

Conventionally, when placing lining concrete in mountain tunnel construction, for example, in order to create a structure that maintains the quality and durability of the concrete for a long time, after demolding the center, sufficient wet curing is performed. It is important to promote the hydration reaction by performing The same applies to the construction of underground structures such as culverts and underpasses.

As one of the curing methods for the lining concrete, curing by spraying water has long been employed. For example, in Patent Document 1 below, a fluid supply pipe having a plurality of fluid outlets for spraying a fluid onto lining concrete molded along the longitudinal direction of the tunnel on the inner periphery of the tunnel is provided, and each fluid of the fluid supply pipe A lining concrete curing apparatus in a tunnel is disclosed that includes a fluid collection tray for collecting fluid exiting an outlet.

However, in the case of the lining concrete curing apparatus described above, there are problems such as requiring a large equipment cost and construction labor, and requiring a large amount of water. Therefore, several curing apparatuses for lining concrete have been proposed, in which water is sprayed in the form of mist to adhere water to the concrete surface, eliminating the equipment for collecting water that has been sprayed.

Specifically, in Patent Document 2 below, in a curing apparatus for tunnel lining concrete that cures the placed tunnel lining concrete by spraying water, a spraying mechanism for spraying misty water onto the tunnel lining concrete, and the It has a moving mechanism for movably installing the spray mechanism in the tunnel, and the spray mechanism and the moving mechanism can move in the tunnel while spraying a predetermined amount of water mist onto the surface of the tunnel lining concrete. A curing apparatus for tunnel lining concrete is disclosed.

In addition, in Patent Document 3 below, concrete is used in tunnel lining work to cover the inner wall surface of the tunnel with concrete, and is cast in the space between the lining formwork that moves in the tunnel and the inner wall surface of the tunnel. After hardening of the hardened lining concrete, a wet curing device for lining concrete that cures the concrete surface in a wet state so as to suppress the occurrence of cracks on the surface of the hardened lining concrete, which is installed on the ceiling surface and the formwork a track extending toward the rear of the track, a mobile body movable along the track, and a spray device installed on the mobile body for spraying a spray liquid toward the lining concrete, wherein the track is A wet curing apparatus for lining concrete is disclosed which is movably supported by support members added in the direction of movement of the formwork as it advances.

JP 2009-155820 A JP 2006-89995 A JP 2009-108612 A

By spraying mist water (hereinafter also referred to as mist) onto the concrete surface, it adheres to the lining concrete surface in an appropriate amount, and a part of it floats in the air to keep the surrounding environment at an appropriate temperature and humidity. be possible. In addition, since the curing water does not turn into water droplets and fall along the concrete wall surface, there is an advantage that the curing apparatus can be made smaller.

However, when spraying water in the form of a mist from nozzles, a curing trolley with nozzles arranged in the circumferential direction is used to prevent the surface of the lining concrete from drying out, that is, to keep the mist from escaping from the concrete surface. Automatic or semi-automatic repetitive movement is necessary, but in order to perform this mist spraying more efficiently, (1) if the mist from the nozzle is expanded and sprayed over a wider area, the spray can be By enlarging the attachment area, mist spraying can be performed effectively.
(2) If the adhesion efficiency of sprayed mist to lining concrete can be improved, mist spraying can be performed effectively.

Therefore, the main object of the present invention is to expand the mist from the nozzle and spray it over a wider range when wet curing is performed by spraying misty water on the concrete surface, and further to improve the adhesion efficiency of the mist to the concrete surface. To improve the efficiency of mist spraying by improving the efficiency of mist spraying.

In order to solve the above problems, as the present invention according to claim 1, in performing wet curing by spraying misty water from a nozzle toward the concrete surface after demolding,
By arranging a charging electrode in the vicinity of the injection port of the nozzle and charging the sprayed water particles positively or negatively, the spraying area is expanded by the repulsive force between the charged water particles. A wet curing method for concrete is provided.

In the invention according to claim 1, when wet curing is performed by spraying misty water toward the concrete surface, the repulsive force of each charged water particle is applied by giving a positive or negative charge to the misty water. Try to expand the spray area by. Therefore, it is possible to increase the efficiency of mist spraying by enlarging the spraying area.

As the present invention according to claim 2, by electrifying the sprayed water particles to a charge opposite to the surface charge of the concrete, the adhesion to the concrete surface is improved by Coulomb attraction. Wetting of concrete according to claim 1 A regimen is provided.

In the second aspect of the invention, the water particles to be sprayed are charged to the opposite side of the surface charge of the concrete to improve the adhesion to the concrete surface. Therefore, it is possible to improve the efficiency of mist spraying by improving the adhesive strength of the concrete surface.

As described in detail above, according to the present invention, when wet curing is performed by spraying misty water onto the concrete surface, the mist from the nozzle is expanded and sprayed over a wider range, and the mist adheres to the concrete surface. It is possible to improve the efficiency of mist spraying by improving the efficiency.

It is a tunnel vertical cross-sectional view showing a work procedure in the tunnel. 1 is a longitudinal sectional view of a water sprinkler 1 to which the method of the present invention is applied; FIG. It is the front view. 3 is an enlarged view showing a driving wheel portion of the water sprinkler 1; FIG. 3 is an enlarged view showing a limit switch of the water sprinkler 1; FIG. FIG. 2 is a perspective view of a main part of the sprinkler system 11; 3 is an enlarged view of a part of a watering nozzle 31; FIG. FIG. 2 is a flowchart of a wet curing method for lining concrete; 3 is a perspective view of a main part of the water sprinkler 11 showing another configuration example of the charging electrode 32. FIG. It is an enlarged cross-sectional view of the sprinkler nozzle 31 portion. It is a figure which shows the vertical spray test procedure and result in an Example. It is a figure which shows the parallel spray test procedure in an Example, and a result.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

As shown in Fig. 1, in the construction of a mountain tunnel, after excavation by blasting, etc., shotcrete is applied to the inner wall of the excavated tunnel by spraying. After invert excavation at the bottom of the tunnel, invert concrete is placed and backfilled, a waterproof sheet is stretched on the inner peripheral surface of the shotcrete using a sheet trolley 2 (this surface is on the ground side ), while sequentially moving the lining center 3 (movable steel formwork) in the tunnel axial direction, each span in the tunnel axial direction, leaving a distance from the rock wall surface The formwork for the lining center 3 is installed along the direction, the lining concrete 4 is placed in the space between the side wall of the natural ground and the formwork, and after it is hardened and removed from the mold, the sprinkler device 1 performs wet curing according to the present invention. Vehicles such as dump trucks and concrete mixer trucks are constantly running inside the mine to carry out muck and transport concrete.

The sprinkler device 1 is installed behind the lining center 3 and sprays misty water toward the surface of the lining concrete 4 for wet curing of the lining concrete 4 for a predetermined period after demolding. It is a device that performs wet curing.

The water sprinkler 1 will be described in detail below with reference to the drawings.

As shown in FIGS. 2 and 3 , the water sprinkler 1 includes a movable platform 10 that can move in the tunnel axial direction, and is supported by the mobile platform 10 . It is composed of a water sprinkler 11 for spraying misty water onto the surface of the lining concrete 4 from a position spaced inward.

As shown in FIG. 3, the mobile platform 10 is supported on a gate-shaped frame 12 made of a substantially gate-shaped steel frame or the like, and on the outside of the gate-shaped frame 12. It is configured to include an arch-shaped frame 13 made of a steel frame or the like and formed in a substantially arch-like shape along the circumferential direction of the tunnel at positions spaced apart by a distance.

The movable platform 10 can be automatically reciprocated on two running rails 14, 14 arranged along the axial direction of the tunnel by means of wheels and a driving device.

The running rails 14 support the portal frame 12 of the movable platform 10 so as to be able to run, and are laid in two rows on the bottom surface of the tunnel along the longitudinal direction. As shown in detail in FIG. 4, the running rail 14 is composed of a rail body 14a on which wheels 15 provided on the portal frame 12 run, and a channel steel in which the rail body 14a is supported in a groove. It is preferable to have a structure consisting of a pillow material 14b. As a result, both side surfaces of the pillow material 14b are provided in an upright state on both sides of the rail body 14a.

At least four wheels 15, 15, . A frame 12 is configured to automatically reciprocate on running rails 14, 14. - 特許庁

Since the water sprinkler 1 is movably provided on the running rails 14, 14 in this manner, the length of the water sprinkler in the axial direction of the tunnel is set to the casting span of the lining concrete as in the conventional water sprinkler. It does not need to be formed with a length covering the entire length, and can be formed with a length shorter than one span for placing lining concrete, so that the water sprinkler can be made compact.

The moving speed of the water sprinkler 1 can be arbitrarily set, but is preferably about 1 to 20 m/min, particularly about 3 to 8 m/min.

In order to allow the water sprinkler 1 to automatically reciprocate on the running relay 14, the movable platform 10 has front and rear end portions in the moving direction, as shown in FIG. A limit switch 17 is provided which comprises a free end portion 17a and a switch 17b for transmitting a signal for reverse rotation of the wheel 15 by swinging of the free end portion 17a. Limit switch abutment portions 18 with which the free end portion 17a of the limit switch 17 abuts are provided at the front and rear ends of the predetermined curing section of the running rail 14, respectively. As a result, the sprinkler device 1 can automatically reciprocate within a predetermined curing section in which the limit switch abutting portions 18, 18 are provided.

The limit switch abutting portions 18 are provided at the front and rear end portions of an arbitrary predetermined section in which the sprinkler device 1 is to be reciprocated. Although the moving section can be set arbitrarily, it is preferable to set it to about 3 to 12 spans (about 30 to 130 m) in which the lining concrete 4 is placed. As shown in FIG. 5, the limit switch abutting portion 18 is fixed to the running rail 14 by supporting it on the upright side surface of the bolster 14b by two bolts 18a, 18a spaced apart along the longitudinal direction of the rail. It is done by

In addition, as an emergency measure when the limit switch 17 does not move the movable platform 10 in the opposite direction, emergency stop switches are provided at both ends of the movable platform 10 in the moving direction, respectively, projecting forward in the moving direction. A device 19 is provided, and it is preferable to provide an emergency stop device abutting portion 20 with which the emergency stop device 19 abuts outside the limit switch abutting portion 18 of the running rail 14 (see FIG. 2). . As a result, even if the limit switch 17 gets over the limit switch abutting portion 18 and moves outward, the emergency stop device 19 abuts on the emergency stop device abutting portion 20 and the movable platform 10 is prevented from moving. can be stopped completely.

Furthermore, by providing sensing devices (not shown) capable of sensing objects and people in front and behind the water sprinkler 1, the water sprinkler 1 may be provided with a function to automatically stop.

As shown in FIG. 2, the movable platform 10 is connected to a power cable 21 for the geared motor 16, a water supply pump 34 for watering, which will be described later in detail, and the like. It is preferable that the power cable 21 is wound around an automatic reel 22 that automatically stretches and winds in conjunction with the movement of the mobile platform 10 . As a result, the power cables 21 are routed without slack, and it is possible to prevent the power cables 21 from being entangled and causing the movement of the movable platform 10 to stop or the power cables 21 from being broken.

The inner space of the portal frame 12 of the movable platform 100 is a space through which a tunnel construction machine such as a dump truck, a concrete mixer truck, or an excavator can pass.

As shown in FIG. 3, the arch-shaped frame 13 of the movable platform 10 is penetrated in the axial direction of the tunnel at a portion corresponding to the tunnel shoulder portion in the tunnel circumferential direction so that the wind pipe 5 for ventilation of the tunnel can pass through. Preferably, a notch 23 is provided. In particular, as shown in FIG. 3, the tunnel ventilation duct 5 is arranged inside the arched frame 13 and said cutouts 23 are wide enough to pass through the suspension bolts that suspend the ventilation duct 5. preferably formed. As a result, the width of the notch 23 can be reduced, and the water sprinkler 11 can spray water without gaps.

Inside the arch-shaped frame 13, a curing sheet 24 is provided which also serves as a waterproof. The curing sheet 24 is provided on substantially the entire surface of the main body of the arch-shaped frame 13 , which does not reach the sprinkler system 11 protruding from the arch-shaped frame 13 . By providing the curing sheet 24, the sprayed mist is covered with the curing sheet 24 immediately after watering from the sprinkler equipment 11 provided on the front side in the movement direction, so the surface of the lining concrete 14 is raised. It can be kept in a state of humidity. In order to reliably function the effect of being covered with the curing sheet 24 immediately after watering, of the sprinklers 11, 11 provided respectively on the front side and the rear side in the running direction of the water sprinkler 1, Water may be sprinkled only from the water sprinkler 11 provided on the front side, and water may not be sprinkled from the water sprinkler 11 provided on the rear side. The curing sheet 24 may be provided discontinuously in the cutout portion 23 of the arch-shaped frame 13, or may be provided continuously so as to bypass the ventilation tube 5. As shown in FIG.

Next, the water sprinkler system 11 will be described.

The water sprinklers 11 are arranged along the circumferential direction of the tunnel at a position separated from the surface of the lining concrete 4 inside the tunnel, and a plurality of water supply pipes 30 are arranged at predetermined intervals along the water supply pipes 30. and water spray nozzles 31, 31 . . . for spraying water toward the surface of the lining concrete 4. The sprinklers 11 are provided at both ends of the movable platform 10 in the moving direction or at one of the ends, in the illustrated example, at both ends in the moving direction.

As shown in FIGS. 2 and 3, the water supply pipe 30 is provided at either end or either end of the arch-shaped frame 13 in the running direction of the sprinkler device, along the arch-shaped frame 13, It is disposed at a position protruding outward in the running direction of the sprinkler device 1 from the arch-shaped frame 13 . The water supply pipe 30 may be provided discontinuously at the notch 23 of the arch-shaped frame 13, or may be provided continuously so as to bypass the ventilation pipe 5. As shown in FIG.

A plurality of water spray nozzles 31, 31 . . . As shown in FIG. 6, the water nozzle 31 is provided to the water supply pipe 30 through a connecting pipe 30a, and sprays water supplied through the water supply pipe 30 from the tip of the nozzle in the form of mist. Watering by the watering equipment 11 is performed either on the front side and the rear side of the running direction of the watering device 1, or on either side. The amount of water sprayed from the water spray nozzle is preferably 0.01 to 1 liter/minute, particularly 0.1 to 0.3 liter/minute, and the injection angle is preferably about 60 to 120°.

The arrangement interval of the water spray nozzles 31 along the water supply pipe 30 is preferably 10 to 100 cm, particularly 30 to 70 cm. When the sprinklers 11 are provided on the front and rear sides of the sprinkler device 1, respectively, the sprinkler nozzles 31 provided on the front and rear sides may be arranged at the same positions on the front and rear sides of the sprinkler device 1, but at a half pitch. It is preferable to displace them one by one so that the surface of the lining concrete 4 can be sprinkled with water evenly.

As shown in FIGS. 2 and 3, the movable platform 10 is provided with a tank 33 for storing water for sprinkling, and a water supply pump 34 for supplying the water in the tank 33 to the water supply pipe 30. The water stored in the tank is pressure-fed through the water supply pipe 30 by the water supply pump 34 and sprayed from each water spray nozzle 31 in a spray form.

As shown in FIGS. 6 and 7, the water nozzle 31 is provided with a nozzle jet in the vicinity of the jetting portion of the nozzle in order to make the spray water positively or negatively charged. Charging electrodes 32, 32 are arranged on both sides of the sandwich. When the water supplied through the water supply pipe 30 is sprayed toward the surface of the lining concrete 4, the water is sprayed from the water spray nozzle 31 by applying a high voltage current to the charging electrodes 32, 32. The water particles are charged with either positive (plus) or negative (minus) charges to generate charged water particles.

As the charging electrode 32, any shape can be used as long as it can charge the water particles ejected from the water spray nozzle 31. In addition, two rod-shaped electrodes are used. The charging electrodes 32 are preferably arranged in two lines on both sides near the spout of the water nozzle 31 . By positively energizing the charging electrode 32, it is possible to generate negatively charged charged water particles, and by negatively energizing the charging electrode 32, the charged water is positively charged. Particles can be generated. The charging electrode 32 is preferably fixed to the water supply pipe 30 (or the moving platform 10) as shown in FIG.

As the material of the charging electrode 32, generally used materials such as copper, copper alloys, and stainless steel can be widely used, but it is preferable to use stainless steel, which is resistant to rust. As for the shape of the charging electrode 32, it is preferable to use a rod-like one having a circular cross section, and it is preferable to use one having a diameter of about 2 to 20 mm, particularly about 8 to 12 mm. The charging electrode 32 may be provided discontinuously in the cutout portion 23 of the arch-shaped frame 13, or may be provided continuously so as to bypass the air pipe 5 for ventilation.

By giving a negative or positive charge to the water particles sprayed from the water spray nozzle 31, as shown in FIG. The diameter of the spray area can be increased to φ2 (>φ1) by force, and the spray area can be expanded by applying electric charge to the sprayed water particles, making it possible to improve the efficiency of mist spraying.

Since the effect of enlarging the spray area is caused by the repulsive force of each charged water particle, the charge given to the water particles may be either positive or negative. It is more preferable to improve the adhesion to the concrete surface by the Coulomb attraction by electrifying the charge on the opposite side of the surface charge of the .

The surface of the lining concrete 4 is normally positively charged due to the presence of cations such as Ca ²⁺ , Na ⁺ , K ⁺ Ma ²⁺ . Therefore, when the water particles to be sprayed are charged to the negative side and sprayed, Crohn's attraction acts between the concrete surface and the sprayed water particles, and the water particles are adsorbed to the concrete surface. Adhesion efficiency of the sprayed water to the concrete surface is improved.

The surface of ordinary concrete is thought to be positively charged due to the effects of cations of metal elements in the concrete. Influence of Various Factors on Salt Penetration of Concrete”, Yuki Yoshida, Fumio Taguchi et al. Concrete Engineering Annual Proceedings Vol. is reported to be negatively charged, so when charging the spray water, the potential of the concrete surface should be measured using a surface potential meter (for example, Koganei Co., Ltd., non-contact handy surface potential meter DTY-KVS11). ), etc., and it is desirable to give the spray water a charge opposite to the surface potential of the lining concrete.

The water sprinkler 1 is provided with a control panel 35 for controlling the operations of the geared motor 16 and the water supply pump 34 . The control panel 35 further includes determination means and the like, which will be described later, and controls the operation of the water sprinkler 1 .

As shown in FIG. 8, the operation control of the water sprinkler 1 first measures whether the surface of the lining concrete 4 is positively charged or negatively charged. The electrification state of the charging electrode 32 is switched based on the surface potential measurement result of the lining concrete 4 . For example, when the lining concrete 4 is positively charged, spray water having a negative charge opposite to this charge is sprinkled, and when the lining concrete 4 is negatively charged is to spray spray water charged with a positive charge opposite to this charge.

Judgment of operation or stop of the sprinkler device 1 is made when the humidity on the surface of the lining concrete 4 exceeds a predetermined threshold according to the measurement result of a hygrometer (not shown) that measures the humidity on the surface of the lining concrete 4. , the water sprinkler 1 is operated for wet curing of the lining concrete 4 . On the other hand, when the humidity on the surface of the lining concrete 4 is equal to or lower than a predetermined threshold value, the operation of the water sprinkler 1 may be stopped. Preferably, the threshold is set at a relative humidity of about 85% RH, for example.
[Other form examples]
(1) In the above embodiment, the charging electrode 32 is arranged in an exposed state, but it is also possible to arrange the charging electrode 32 so as not to be exposed in order to prevent electric leakage and electric shock. For example, as shown in FIG. 9, an electrode holding member 37 made of an insulating material such as synthetic resin or rubber is attached to the tip of the water nozzle 31 . As shown in FIG. 10, the electrode holding member 37 has a cylindrical shape surrounding the tip of the nozzle, and charging electrodes 38, 38 are arranged on the inner peripheral surface thereof. . A power cable 36 is arranged along the water supply pipe 30, and power is supplied to the charging electrode 38 from a branched electric wire 36a. The power cable 36 is fixed to the supply pipe 30 by binding bands 39 arranged at appropriate intervals.
(2) In the above embodiments, the present invention was explained by taking wet curing of lining concrete in mountain tunnels as an example, but the wet curing method according to the present invention can also be applied to underground structures such as culverts and underpasses. It can be applied similarly.

Hereinafter, the effect of enlarging the spray area when the mist sprayed from the water nozzle according to the present invention is charged, and by charging the sprayed water with the charge on the opposite side of the surface charge of the concrete, the Coulomb attraction to the concrete surface. Verification experiments on the effect of improving the adhesive force will be described. In the experiment, two experiments were conducted: a <vertical spray test>, in which water was sprayed perpendicularly to the curing surface, and a <parallel spray test>, in which water was sprayed parallel to the curing surface. verified their effects. The test procedures and test results are described in detail below.
<Vertical spray test>
As shown in FIG. 11, a two-fluid nozzle (BIMV80075S303+TS303) manufactured by Ikeuchi Co., Ltd. was used as a spray nozzle, and a water sensitivity test paper: length 76 mm × width 52 mm (ground color yellow, moisture and turns dark blue when it adheres.) was attached, and the water pressure was 0.00 mm from a position 1500 mm away (data No. 1) and a position 1000 mm away (data No. 2) toward the water sensitivity test paper. Spraying was performed for 30 seconds under conditions of 1 MPa and air pressure: 0.1 MPa.

A charging electrode was arranged near the tip of the nozzle, and the test was conducted for three cases of no charging, positive charging, and negative charging, and the area where the color of the water sensitivity test paper changed was calculated and compared. For area comparison, the water sensitivity test paper was scanned, the area of the color-changed portion was calculated using special software, and the area ratio (wet area ratio %) to the total area was calculated. The water sensitivity test paper was found to be negatively charged as measured by a surface potential meter.

The test results are shown in FIG. In data No. 1 (1500 mm), both the positively charged and negatively charged cases have a slightly larger wet area ratio than the non-charged case, and when charged, the repulsion of charged water particles It was found that the spray area was enlarged by force.

A comparison of positive charging and negative charging shows that the ratio of positive charging to negative charging is 111.9%. It was found that the adhesion to the surface was improved by charging due to Coulomb attraction.

In the case of data No. 2 (1000mm), both the positively charged and negatively charged cases have a slightly larger wetted area ratio than the non-charged case. It has been found that the repulsive force of the particles can expand the spray area, but in the comparison of the cases of positive charging and negative charging, most of the sprayed water reaches the water sensitivity test paper, and there is no significant difference. I didn't.
<Parallel spray test>
As shown in FIG. 12, a two-fluid nozzle (BIMV80075S303+TS303) manufactured by Ikeuchi Co., Ltd. was used as a spray nozzle, and a water sensitivity test paper: length 76 mm × width 52 mm (ground color yellow, moisture It turns dark blue when it adheres.) is attached, and the position directly above the position 400 mm away from the wall surface (data No. 3) and the position 200 mm away (data No. 4) (water sensitivity test paper Spraying was performed for 30 seconds from 300 mm above the center downward under conditions of water pressure: 0.1 MPa and air pressure: 0.1 MPa.

A charging electrode was arranged near the tip of the nozzle, and the test was conducted for three cases of no charging, positive charging, and negative charging, and the area where the color of the water sensitivity test paper changed was calculated and compared. For area comparison, the water sensitivity test paper was scanned, the area of the color-changed portion was calculated using special software, and the area ratio (wet area ratio %) to the total area was calculated. The water sensitivity test paper was found to be negatively charged as measured by a surface potential meter.

The test results are shown in FIG. In data No. 3 (400 mm), the water sensitivity test paper did not get wet in the non-charged case, but the wetted area ratio was 3.804% in the positively charged case, and the wetted area in the negatively charged case. The ratio was 2.379%, and it was found that the spray area was expanded by the repulsive force of the charged water particles when charged.

In addition, in the comparison between positive charging and negative charging, the ratio of positive charging to negative charging was 159.9%. It was found that the adhesion to the surface was improved by charging due to Coulomb attraction.

In the case of data No. 4 (200 mm), the water sensitivity test paper was hardly wet in the non-charged case, but in the positively charged case, the wetted area ratio was 90.04%, and in the negatively charged case. The wetted area ratio was 79.748%, and it was found that the sprayed area was expanded by the repulsive force of the charged water particles when charged with both positive and negative charges.

In addition, in the comparison between positive charging and negative charging, the ratio of positive charging to negative charging was 112.9%. It was found that the adhesion to the surface was improved by charging due to Coulomb attraction.

DESCRIPTION OF SYMBOLS 1... Sprinkler, 2... Seat cart, 3... Lining center, 4... Lining concrete, 10... Movable stand, 11... Sprinkling equipment, 12... Gate-shaped frame, 13... Arch-shaped frame, 14... Running rail, 15 Wheel 16 Geared motor 17 Limit switch 18 Limit switch contact portion 19 Emergency stop device 20 Emergency stop device contact portion 21 Power cable 22 Automatic reel 23 Notch Portion 24 Curing sheet 30 Water supply pipe 31 Sprinkle nozzle 32 Charging electrode 33 Tank 34 Water supply pump 35 Control panel 36 Power cable 37 Electrode holding member 38 …Charging electrode

Claims (2)

When wet curing is performed by spraying water mist from a nozzle toward the concrete surface after demolding,
By arranging a charging electrode in the vicinity of the injection port of the nozzle and charging the sprayed water particles positively or negatively, the spraying area is expanded by the repulsive force between the charged water particles. Wet curing method for concrete characterized by: 2. The wet curing method of concrete according to claim 1, wherein the water particles to be sprayed are charged to the opposite side of the surface charge of the concrete to improve adhesion to the concrete surface by Coulomb attraction.

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