JPH0629503B2 - Wet carrier for cement-based suspension - Google Patents

Description

TECHNICAL FIELD The present invention relates to a wet transfer device for cement-based suspension used for dam grout injection work and the like.

[Conventional technology]

The grout used in the dam construction work includes a cement suspension prepared by mixing cement with water or a cement bentonite suspension prepared by mixing cement and bentonite with water. These are injected into the ground by adjusting the concentration, pressure and injection amount according to the state of the ground and the like.

In this injection, generally, from a grout storage tank having a mixing function, a wet type (not air transportation) by a grout pump, while sucking through a suction pipe, a carrier pipe and a grout control valve, from the injection pipe to the ground. Injected. At this time, the surplus grout is returned from the grout control valve to the grout storage tank through the return pipe and is reused as grout.

[Problems to be Solved by the Invention]

In dam grout injection, the flow rate and pressure are controlled by the grout control valve. Also, if mixing is not performed properly in the grout storage tank, part of the grout hardens to become a solidified product, and this solidified product reaches the grout control valve as it is, or hardens in the suction pipe or the transfer pipe and its inner wall There is a risk that the solidified material will get stuck to the grout control valve, and the solidified material will clog the grout control valve and interfere with normal operation, causing the injection pressure to momentarily exceed the specified value and destroy the rock mass. It was Further, in the dam grout, the solidified product is remarkably generated in order to return the grout.

In addition, when pouring dam grout into the ground, it is a rule to pour grout with as small particles as possible into a narrow gap, but when the above solidified material is mixed with grout and injected, good grout injection is performed. There was also a problem that I could not do it.

Therefore, an object of the present invention is to avoid a situation in which the solidified product impedes the normal operation of the grout control valve, and moreover, surely injects the grout having a predetermined particle size into the target ground.

[Means for Solving the Problems]

The above-mentioned problem is that the grout consisting of the cement-based suspension is injected from the grout storage tank into the ground from the injection pipe through the suction pipe, the grout pump, the transfer pipe, and the grout control valve, and the excess grout is the control valve From the device for returning the cement-based suspension, which is returned from the grout storage tank through the return pipe from the grout, and is reused as grout, in the middle of the suction pipe or the transfer pipe, a separation tank is provided vertically, and the bottom thereof is provided. A grout inlet is formed on a side wall above the lid, and a grout outlet is formed at a position higher than the inlet, and the cross-sectional area of the separation tank is connected to the inlet and the outlet by the suction pipe or the conveyor. It has a size larger than the cross-sectional area of the pipe, and is higher than the inlet of the separation tank and lower than the outlet, and has a size of a size that does not allow a part of the solidified grout to pass through. A horizontal net material is provided, and the area between the grout inlet and the bottom wall below is defined as the solidified material deposit portion, and the deposit on this deposit portion can be discharged by opening the bottom wall. This can be solved by adopting a configuration in which other materials are not introduced into the tank and only the grout flows.

[Action]

In the present invention, a separation tank is provided vertically in the middle of the suction pipe or the transfer pipe, and the separation tank has a larger cross-sectional area than the communication of the suction pipe or the transfer pipe. Therefore, when the grout flows into the separation tank through the inflow port, the flow velocity of the grout rapidly decreases, and since the outflow port is higher than the inflow port, the cement suspension particles are not reached until reaching the outflow port. The solidified solids of mine fall under gravity.

On the other hand, a part of the solidified material may reach the outlet and eventually reach the grout control valve due to fluctuations in the transport pressure due to pulsation during transport.

Therefore, in the present invention, further, at a position higher than the inflow port of the separation tank and lower than the outflow port, a net material having a size of a grain that does not allow the solidified substance of the grout to pass through is horizontally provided. The solidified product is reliably sieved off.

Furthermore, since the grout inlet is formed above the bottom wall and the area between the bottom wall below the grout inlet is the solidified material deposit portion, the deposit on this deposit portion can be opened by opening the bottom wall. , Can be discharged at an appropriate time.

〔Example〕

 Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a system diagram of a dam grout injection mode according to the present invention. 1 is a grout stock solution storage tank having a mixing function, 2 is a suction tube provided between the grout stock solution storage tank 1 and a grout pump 3, 4 is a transport pipe connected to the grout pump 3, and 5 is a transport tube 4 and a return pipe A grout control valve having a diversion function connecting the pipe 6 and the injection pipe 7, 8 is a pressure sensor provided in the injection pipe 7, 9 is a flow sensor provided in the injection pipe 7, 10 is a grout injection port, 11 is ground The suction pipe 2 is provided with the separation tank 12 shown in FIG.

In the above grout injection system, the grout stock solution storage tank 1
Make a stock solution of grout with, and operate the grout pump 3 with stirring to remove the grout sucked from the suction pipe 2.
Grout is injected into the ground 11 from the grout injection port 10 through the transport pipe 4, the grout control valve 5, and the injection pipe 7. At that time, the grout is injected by the controller 13 while controlling the pressure and the flow rate to the injection tube 7 by adjusting the partial flow rate (return amount) in the grout control valve 5. Excess grout is returned from the grout control valve 5 to the grout stock solution storage tank 1 through the return pipe (retar pipe) 6 and reused as grout.

As described above, if mixing is not properly performed in the grout storage tank 1, a part of the grout is hardened and solidified, and the solidified material reaches the grout control valve 5 as it is, or the suction pipe 2 or It hardens in the transfer tube 4 and adheres to its inner wall, which eventually peels off and reaches the graft control valve 5, and this solidified material blocks the grout control valve 5 and prevents normal operation, and the injection pressure is momentarily set to a prescribed value. There was a risk that the bedrock would collapse beyond.

Therefore, in the present invention, for example, a separating device 12 shown in FIG. 2 is provided in the middle of the suction pipe 2 to prevent the solidified substance from being transferred to the grout control valve 5.

The separating device 12 is one in which a grout inlet 15 is formed on a side wall above a bottom lid 21 of a cylindrical separation tank 14 which is vertically sealed, and a grout outlet 16 is formed on a side wall above the grout inlet 15. In addition, a net material 17 for preventing the passage of the solidified product is horizontally provided between the inflow port 15 and the outflow port 16 of the separation tank 12, and the net material 17 forms an upper part of the separation tank 14. A packing material 20 is provided between the can 18 and the lower can 19.
A bottom lid 21 is removably attached to the lower end of the lower can 19 with being sandwiched and fixed.

When the grout flows into the separation device 12 provided in the suction pipe 2 from the inflow port 15, the grout rapidly decreases in flow velocity in the separation tank 12 having a larger volume than the unit volume of the suction pipe 2, and the inner wall of the separation tank 14 is increased. The solidified material 22 precipitates due to the decrease in the flow velocity and the presence of the net material 17 due to the flow of the solidified material 22 colliding with the bottom lid 2.
Only grout that has been deposited on the surface 1 and from which the solidified material 22 has been removed is discharged from the outlet 16. As a result, normal operation of the grout control valve 5 is ensured, and solidified matter and large-sized particles other than the intended one are not injected into the ground.

In the present embodiment, the separating device 12 is provided in the middle of the suction pipe 2, but may be provided in the middle of the transport pipe 4, or may be provided in both the suction pipe 2 and the transport pipe 4. Good.

〔The invention's effect〕

As described above, according to the present invention, it is possible to avoid a situation in which the control valve normally operates due to solidified matter, and to surely inject the grout having the predetermined particle size into the target ground.

[Brief description of drawings]

FIG. 1 is a systematic diagram of a grout injection system according to the present invention, and FIG. 2 is a vertical sectional view of a separation device according to the present invention. 1 ... Grout stock solution storage tank, 2 ... Suction pipe, 4 ... Transfer pipe, 5 ... Grout control valve, 6 ... Return pipe, 7 ... Injection pipe, 12 ... Separation device, 14 ... Separation tank , 15 grouting inlet, 16 grouting outlet, 17 mesh material, 21 bottom wall, 22 solidified material.

Claims (1)

[Claims] 1. A grout consisting of a cement-based suspension is injected from a grout storage tank into a ground through an inlet pipe, a grout pump, a transfer pipe, and a grout control valve, and excess grout is controlled by the above-mentioned control. Returning from the valve through the return pipe to the grout storage tank, in the transport device of the cement-based suspension to be reused as grout, in the middle of the suction pipe or the transfer pipe, a separation tank is provided vertically, A grout inlet is formed on a side wall above the bottom lid, a grout outlet is formed at a position higher than the inlet, and the cross-sectional area of the separation tank is the suction pipe or the suction pipe communicating with the inlet and the outlet. It has a size larger than the cross-sectional area of the carrier pipe, higher than the inflow port of the separation tank, and lower than the outflow port, and has a size that does not allow a portion of the grout to pass through. A horizontal net material is provided, and the area between the grout inlet and the bottom wall below is defined as the solidified material deposit portion, and the deposit on this deposit portion can be discharged by opening the bottom wall. A wet transport device for cement-based suspension, characterized in that only grout is circulated without adding other materials into the tank.