JPS60238574A - Cutting of mass concrete - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for cutting mass concrete.

Conventionally, in the demolition of so-called mass concrete, which has large cross sections, foreign objects such as reinforcing bars have been cut by gas cutting after crushing the concrete. This is because concrete has different physical properties such as toughness and ductility compared to concrete, so it is difficult to crush or cut concrete and reinforcing bars at the same time.
It required a lot of work to remove it. However, in dangerous concrete structures such as dams and nuclear power plant structures, where it is difficult for workers to get close to the structure during demolition, or where working close to the structure is restricted, only this reinforcing steel can be removed by other workers. It is difficult to cut the concrete by crushing or cutting it, and it is necessary to reliably cut foreign objects such as reinforcing bars at the same time as crushing or cutting the concrete.

The present invention was made to solve the above problems, and by adding an uncut detection function to the cutting method using a high-pressure water jet, it is possible to reliably cut foreign objects such as reinforcing bars in concrete. This invention provides a cutting method that increases cutting efficiency by eliminating uncut parts, and also secures the safety of four concrete blocks and work.

The present invention includes a cutting nozzle that injects abrasive material with a high-pressure water jet, a detection device that detects uncut portions at a subsequent position in the cutting direction, and a control device that controls forward and backward movement based on signals from the detection device. , using a concrete cutting device equipped with a drive device that moves forward and backward under the control of a control device, a detection device detects uncut portions of the concrete cut, and a signal from the detection device controls the drive device by the control device. This is a mass concrete cutting method characterized by moving the concrete cutting device backward by a predetermined distance and moving forward again to cut the uncut portion of the cut portion.Examples of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram explaining the functions of the equipment constituting the cutting device 45 used in this cutting method. In this figure, li" is a hydraulic pressure generator, and the hydraulic pressure generated here is By applying hydraulic pressure alternately to the circuits 3 and 4 using the directional control valve 2, reciprocating motion is given to the hydraulic piston 6 in the pressure intensifier 5. 7 is a water supply pump, and water is supplied by two pumps installed in parallel. The reciprocating motion of the hydraulic piston 6 is alternately sent to the pump 9.9' of the pressure intensifier 5 via check valves 8 and 8'.In this pressure intensifier 5, the hydraulic piston 6
The pressure on the water supply side increases in inverse proportion to the ratio of the cross-sectional area of n1 to the cross-sectional area of the pump chamber 9.9' side. After repeated suction and compression, high-pressure water is sent to the injection nozzle 12 via the check valves 10, 10', the accumulation rake 11, and the valve 11'. The accumulation layer 11f1 absorbs the pressure pulsation of the high-pressure water generated and stores the high-pressure water, and has the function of sending a stable, pulsation-free, π-pressure water flow to the injection nozzle 12. The injection nozzle 12 is provided with an abrasive tank 13 on the side of the nozzle, in which abrasive materials in the form of powder, such as iron powder, stone powder, carborundum, etc., are stored.
This abrasive material is supplied to the injection nozzle 12VC.

FIG. 2 is a partially cross-sectional perspective view illustrating the structure of the injection nozzle 12, in which the powder and granules supplied from the abrasive tank 13x are injected into the mixing chamber 12' through the nozzle 14J: a high-pressure water jet. It is added to and mixed with n1 nozzle tip 15J: and is injected. Figure 3 shows a situation in which 15 pieces of mass concrete are cut by the cutting device 45 equipped with a device to detect uncut parts. This is a schematic side cross-sectional view of the hailstone, showing the detection device for 20 uncut holes and 1. The angle sensor 20 has several rod-like tentacles 21, 2 and 2 rod-like tentacles.
1 is an ordinary mask IJ-) 15. During the cutting process, the cutting device 45 follows the cutting device 45 at a hanging position as shown at 21 in the figure, and when it comes into contact with the reinforcing bar 16' for cutting, for example, it rotates as shown at 21'. This rotation angle or angle sensor 2
0, the detection σj and the angle signal are input to the control device 22.
Ru. Furthermore, the cutting device 45 is configured to move forward and backward by controlling the control device 22 and the driving device 23. in this case,
An uncut area is detected by the angle If sensor 20 of the detection device σj
Then, m! 1 N device 22. Also controls 11'
When the ag signal is sent, the valve 11' is closed, the injection of the high-pressure water jet is stopped, the cutting device 45 is moved backward, and when it starts moving forward again, the valve 11' is opened and the high-pressure water jet is injected. It's about to start work.

FIG. 4 shows a second embodiment of the detection device for detecting the above-mentioned uncut portion, in which the rod-like tentacle 21 is fixed to the cutting device 45 at the mount 25 via the elastic metal plate 24. , a strain gauge 26 is attached to the metal plate 24, and the strain gauge 26 is attached to the metal plate 24.
The output signal of is input to the distortion meter 27 σt1;! With the above configuration, when the rod-like tentacle 21 detects an uncut portion, the metal plate 24 is distorted, and at the same time, the electrical resistance value of the strain gauge 26 changes in proportion to the degree of distortion, and the output A signal is input to the distortion meter 27, and based on this signal, the drive device 2
3 and valve 11' may also be controlled.

FIG. 5 shows a third embodiment of the detection device for detecting the above-mentioned uncut portion, in which the rod-like tentacle 21 is attached to the cutting device 45 so as to be rotatable around the bin 28, and the rod-like tentacle 21 is A limit switch 29, 29'fr is provided on the rod-like tentacle 21, which operates when the rod-like tentacle 21 detects and rotates. It was designed to prevent people from starving.

Figure 6 shows the cutting method using the above device. Explaining process 8
This is an explanatory diagram, and in the first device start-up (30), the hydraulic pressure generating device 1, the pressure intensifier 5, and the water supply pump 7 rotate in succession, and water at a certain pressure is stored in the accumulator 11. Next, the cutting position of Mask Conc IJ -) 15 is confirmed, preparation for cutting is made, and the cutting nozzle 12 sprays hot water t''1 (
31), preparation for cutting is completed. Subsequently, the cutting device 45 starts moving forward (32) and first cuts the concrete (33).
The cutting of the reinforcing bars (34) is carried out one after the other, and the cutting proceeds from the beginning. In the cutting process of C, judgment (35) is made 1, that is, the rod-like tentacle 21 detects that there is no uncut portion.
In the case (36), the cutting device 45 is stopped first, the square 11' is closed and the injection of the high aqua regia jet is stopped (37).
) anru. At this point, the cutting device 45 starts to retreat 38)
, a predetermined distance, that is, the cutting nozzle 12 or the original amount left uncut? It moves back and stops at the cutting position (39) oDuring this time, the hydraulic pressure generator 1, pressure intensifier 5, and water supply pump 7 continue to operate, and the generated high-pressure water is transferred to the accumulator 1.
It is stored in 1. Next, open the valve 11' again (opening force) f high-pressure water jet, abrasive material is injected fl (3], ), cutting and filling, 4
5 is forward (32) L, uncut conch IJ-1 (33)
Or cut the reinforcing bar part (34). If the uncut NFC is detected again during this cutting process, please check the above cycle again. The cutting device 45 repeatedly moves backward and forward to perform cutting.1.This operation? It is repeatedly confirmed by the rod-shaped tentacle 21 that there is no uncut portion 'i'11'I (4o) The cutting device 40 continues to move forward and the cutting is completed (41). Note that when the cutting is completed, the cutting device 45 stops and the valve 11 is closed.
' closes and the high-pressure water jet stops spraying (42) 1
Then preparations for cutting are made for the next process (43). During this disconnection pause, the hydraulic generator 1, the pressure intensifier 5, and the water supply pump 7
It is possible to operate the system at short intervals and store the generated high-pressure water in the accumulator 11, or it is possible to completely stop the system.

As explained above, according to the cutting method according to the present invention, the abrasive material is cut by a high-pressure water jet. Mass concrete can be cut with high efficiency using a spray cutting device.
At the same time, only the parts that remain uncut due to the presence of reinforcing bars and other materials with different physical properties are recut, allowing the mass concrete to be reliably cut and dismantled. , it is possible to cut automatically in the same process, which eliminates the need to perform the work twice and greatly improves work efficiency. Furthermore, is this cutting method suitable for cutting devices equipped with remote control tubes or automatic control devices? By applying this method, it becomes easier to dismantle dangerous and complex concrete structures such as dams and nuclear power plants, allowing for safe and efficient cutting and demolition.

[Brief explanation of the drawing]

Figure 1 shows the configuration of the cutting device? The block connection diagram to be explained, Fig. 2 is a partially sectional perspective view of the cutting nozzle, Fig. 3 is a schematic elevation sectional view showing the cutting situation of mass concrete, and Fig. 4 is a diagram of the second embodiment of the detection unit. FIG. 5 is a drawing of a third embodiment of the detection section, and FIG. 6 is a perspective view of the process for explaining the cutting method. 1... Hydraulic system 5... Pressure booster 7... Water supply port 7
7' 11...Accumulation layer 11'-°" valve 1
2... Cutting nozzle 13... Abrasive tank
15...Mass concrete 20...Angle sensor 21...Bar-shaped tentacle 22...Control device 23...
・Drive device 24...Metal plate 26...Strain gauge 2
7... Strain meter 28... Bins 29, 29'... Limit switch 30 to 43... Cutting process step 45... Cutting device. Application 8 Hazama Co., Ltd. Agent Patent Attorney Yujibu Taka Figure 1, Figure 2, Figure 3, Figure 4, Figure 5

Claims (1)

[Scope of Claims] (1) A cutting nozzle that injects abrasive material using a high-pressure water jet, a detection device that detects uncut portions of the cut portion at a subsequent position in the cutting direction, and a forward and backward movement controlled by signals from the detection device. Using a concrete cutting device that is equipped with a control device that performs cutting and a drive device that moves forward and backward under the control of the control device,
The concrete cutting device is characterized in that a detection device detects an uncut portion of the concrete cut portion, and a control device controls a drive device based on a signal from the detection device to move the concrete cutting device backward by a predetermined distance, and then moves forward again to cut the uncut portion of the cut portion. How to cut mass concrete. (2. A method for cutting mass concrete in which the detection device according to claim 1 is an angle sensor equipped with a rod-like tentacle. (3) Percentage The detection device according to claim 1 is A method for cutting mass concrete using a strain gauge attached to an elastic plate attached between a rod-shaped tentacle and a cutting device. A method for cutting mass concrete using a switch operated by.