JPH0728185Y2 - Discharge detection device for underwater concrete placing pipe - Google Patents

Description

[Detailed Description of the Invention] (a) Industrial field of application Improvement of the device that detects the timing of the discharge of the sponge and other sponges stored in the front stage of the concrete delivered into the pipe at the start of underwater concrete placement and at the rear stage at the end Regarding

(B) Conventional technology When pouring underwater concrete into water, the underwater concrete sent from the plant is discharged through the inside of the pouring pipe, but a sponge that is stored under pressure in the previous stage of the underwater concrete passing through the pipe. Is placed and is sent with it. The reason for storing the sponge is to discharge the underwater concrete in a dense state from the inside of the casting pipe and to lower the casting pipe to a predetermined position (the position where the tip is buried) after confirming the start of discharging.

In each case, bubbles and water were not mixed in the underwater concrete. At the end of the other casting, the sponge is again stored under pressure in the casting pipe, and water is sent later to clean the inside of the pipe.
In this case also, the water feed is stopped immediately after the sponge comes out.

In all of the above, when the sponge floats on the water surface, the next operation is visually confirmed.

(C) Problems to be solved by the device When the position of the underwater concrete is deep, it takes a long time for the sponge to float, and the start confirmation of discharge is delayed. Therefore, the timing of the next operation is often delayed. This causes water to be mixed into the poured underwater concrete more than necessary, which causes a problem of quality deterioration.

(D) Means for solving the problem A metal detection sensor provided on the peripheral wall of the end portion of the cast pipe and having a sensitivity in the pipe inner direction, and a cylindrical thin metal plate formed in a cylindrical shape by a flexible material and extending along the outer peripheral surface are provided. It consisted of a feed plug that was built-in and that penetrates the inside of the casting pipe.

(E) Action A feed plug with a thin metal plate is located in front of the underwater concrete that passes through the casting pipe, and it is pumped together with the underwater concrete. On the other hand, a metal detection sensor is provided on the peripheral wall of the front end of the casting pipe, and when the feed plug passes this position, the metal detection sensor reacts with the thin metal plate in the feed plug at that moment. This signal is sent to a predetermined location in a local area via a cable.

(F) Embodiment An embodiment of the present invention will be described below with reference to the drawings. In the figure, reference numeral 1 denotes a pipe. One end of the pipe 1 is connected to the upper end of a driving pipe 2, and the lower end of the driving pipe 2 is connected to a driving pipe 3
Are connected. The placing pipe 3 has a pipe structure having the same diameter as the placing pipe 2, and a detection port 4 is formed in the side wall thereof, and a cylindrical protective case 5 is provided so as to cover the detection port 4. There is. A metal detection sensor 6 having a detection surface facing the detection opening 4 is housed in the protective case 5, and is filled with a resin member 7. The metal detection sensor 6 is a sensor that performs a switching operation in response to an approaching metal, and is, for example, a differential coil type sensor that detects a magnetic flux due to an eddy current generated in a detection object by a difference between a detection coil and a comparison coil. The resin member 7 is also interposed between the detection surface of the metal detection sensor 6 and the detection port 4, and the resin member 7 forms a series of shapes with the inner peripheral surface of the driving pipe 3. A cable 8 is led out from the metal detection sensor 6, and the cable 8 is connected to an external control box 10 and a lamp 11 from a protective case 5 through a protective tube 9. Reference numeral 12 is a feed plug which is fed from the pipe 1 through the inside of the casting pipes 2 and 3. Feeder 1
Reference numeral 2 denotes a flexible material, for example, a rubber plate 14 bonded to the upper and lower end surfaces of a cylindrical sponge 13. Inside the cylindrical sponge 13, a cylindrical metal thin plate along the outer peripheral surface, such as an aluminum foil.
15 are provided. It is configured as described above, and the operation state will be described next. Reference numeral 16 in FIGS. 5 and 6 indicates the bottom surface of the concrete poured in water. As shown in FIG. 5, the tip of the driving pipe 3 is positioned so as to be separated from the driving bottom surface 16. In this state, underwater concrete is pressure-fed from a plant (not shown) and fed into the casting pipe 2. At this time, the feed plug is already stored under pressure in the pipe 1. Then, the underwater concrete is 12
Is restrained by, and becomes a dense state in the pipe 1 and the casting pipe 2,
Gradually descend with the feed plug 12. Eventually, when the feed plug 12 passes through the detection port 4 of the casting pipe 3, the metal detection sensor 6 detects the aluminum foil 15 and turns on. This turns on the lamp 11. Immediately after that, as shown in FIG.
It is released from the tip. Immediately after confirming the lighting of the lamp 11 from outside, as shown in FIG. In this way, a predetermined amount of casting is performed so that the tip of the casting pipe 3 is not exposed on the underwater concrete interface. After the completion of the casting, the casting pipes 2 and 3 are again pulled up to the underwater concrete interface, and the feed plug 12 is pressure-stored in the pipe 1,
Water is pumped later. The feed plug 12 advances while cleaning the insides of the pipe 1, the casting pipes 2 and 3, and eventually reaches the detection port 4 of the casting pipe 3. At the same time, similarly to the above, it is possible to externally know that the lamp 16 is turned on and the feed plug 12 reaches the most advanced portion (that is, all the underwater concrete in the pipe has been discharged). At this point, the pumping of water is stopped. The feed plug 12 is discharged from the tip of the driving pipe 3.

Although the thin metal plate in the feed plug 12 is made of aluminum foil in the above embodiment, various other thin metal plates can be adopted. Further, as the metal detection sensor, as long as it is a sensor that performs a switching operation for an approaching metal, it is possible to use other types such as a high frequency transmission type in terms of function and a ring type in terms of shape. Regarding the attachment of this metal detection sensor, it is also possible to form an integral casting pipe part of which is made of resin and either embed it in the resin part or provide it outside the resin part.

(G) Effect of the invention At the start of the pouring, the metal detection sensor detects the discharge of the feed plug leading the underwater concrete immediately before that, so that the pouring pipe is quickly driven when the actual underwater concrete is discharged. It can be lowered to near the floor. In addition, when the water is pumped into the pipe or the pipe after completion of the driving, the time when the water reaches the leading edge can be accurately detected. Therefore, it is possible to move to the next operation without loss time such as when the feed plug floats up to the surface of the water as in the past, and therefore it is possible to prevent the mixing of water into the underwater concrete for casting to a minimum, and high-quality pouring work. Can be done. In addition, there is no trouble such as carefully monitoring and waiting for the feed plug floating on the water surface, there is no timing deviation with respect to the next operation, and there are practical effects such as improved process control. In addition, the cost is easy because the number of parts is small and it is simple.

[Brief description of drawings]

The drawings show one embodiment of the present invention. Fig. 1 is an external view, Fig. 2 is a detailed vertical sectional view, Fig. 3 is an external view of a feed plug, and Fig. 4 is a vertical sectional view of the feed plug. , FIG. 5 and FIG. 6 are explanatory views of the operation. 2 ... Placing pipe 3 ... Placing pipe 6 ... Metal detection sensor 12 ... Feed plug 15 ... Metal thin plate (aluminum foil)

Claims (1)

[Scope of utility model registration request] 1. A metal detection sensor, which is provided on a peripheral wall of a distal end portion of a driving pipe, and has a sensitivity in the inward direction of the pipe, and a thin metal plate of a cylindrical shape which is formed of a flexible material and extends along the outer peripheral surface, are built-in. Discharge detecting device for underwater concrete pouring pipe, characterized by comprising a feed plug penetrating through the pipe