JP2865192B2 - Face water pressure control device in muddy water shield method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a face water pressure control device in a muddy water shield method.

[0002]

2. Description of the Related Art In a muddy water shield construction method, muddy water is circulated using a pump, and the face is stably held by the water pressure.

Conventionally, the face water pressure is controlled by measuring the face water pressure with a face water pressure gauge attached to the face and changing the rotation speed of the ground-side mud pump to keep the face water pressure constant.

[0004]

However, when the face water pressure is controlled by the pump on the ground as described above, since the distance between the ground and the face is large, the hydraulic pressure of the face is affected by the change in the rotation speed of the pump. The phenomenon that the change is delayed occurs. This tendency becomes remarkable especially when the excavation distance becomes long. Also,
In the case of automatically controlling the face water pressure, the following performance is deteriorated because each control coefficient is obtained in consideration of the delay. Deterioration of the followability of the automatic face water pressure control leads to instability of the face water pressure, which may cause the face to collapse.

[0005] The present invention relates to a muddy water shield construction method,
It is an object of the present invention to provide a control device that improves the followability of face water pressure control and stabilizes the face.

[0006]

[0007]

According to the present invention, mud is fed from a regulating tank to a face by a mud sending pump through a mud sending line, and is adjusted from a face by a mud discharging pump through a treatment plant through a mud sending line. In the face water pressure control system in the muddy water shield method in which the mud is drained into the tank and the face water pressure is maintained and excavated, a bypass circuit is provided to connect the mud feed line immediately after the mud pump on the most face side of the mud line and the mud feed line. A pump and an opening adjustment function valve are arranged in the bypass circuit, and a mud sending water pressure adjusting means for controlling a mud sending pump by a water pressure gauge provided before a branch of the mud sending line bypass circuit; Face water pressure adjusting means for controlling the opening degree control valve by means of a gauge and a water pressure gauge provided on the face side of the bypass circuit branch of the mud feed line, and sludge discharge by a flow meter provided on the sludge pump face side of the sludge discharge line Pump It is provided with a Gosuru waste sludge flow rate adjusting means.

[0008]

The mud pump is operated under the control of the mud water pressure adjusting means so that the water pressure before branching the bypass circuit of the mud line becomes higher than the face water pressure, and the bypass circuit is opened so that the face water pressure becomes an appropriate value. The degree of opening of the degree adjusting function valve is controlled by the face water pressure adjusting means, and a surplus of the mud feeding flow rate is passed through the bypass circuit to the sludge discharge line. When the face water pressure changes, the opening of the opening adjustment function valve is adjusted by the face water pressure adjusting means to adjust the flow rate of the mud to the face, and the face water pressure is maintained at an appropriate value.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, a mud feed line 4 is provided from a regulating tank 1 provided on the ground to a face 2 via a mud feed pump p1, and a treatment plant 3 is provided from the face 2 via a mud discharge pump p2, pe. A sludge line 5 is provided to return to the adjustment tank 1 via the tank. In addition, a bypass circuit 6 is provided immediately after the sludge pump p <b> 2 on the most face side of the sludge line 5, that is, the bypass circuit 6 connecting the vertical shaft side and the sludge feed line 4. The bypass circuit 6 is provided with a pump pb and an opening adjustment function valve 7 from the mud feed line 4 side. Muddy water pressure gauges 11 and 12 are provided upstream and downstream of the branch B of the bypass circuit 6 of the muddy line 4,
The face 2 is provided with a face water pressure gauge 13. A face valve set 8 is provided to control the fluid circuit of the face 2, and the face 2 of the sludge pump p 2 of the sludge line 5 is provided.
A sludge flow meter 14 is provided on the side.

Further, a muddy water pressure regulator 15 which is a muddy water pressure adjusting means for controlling the muddy water pump p1 on the ground by the muddy water pressure gauge 11, and a sludge flow rate control for controlling the sludge pump p2 by the sludge flow meter 14. There is provided a sludge flow rate adjuster 17 as a means, and a face water pressure adjuster 16 as a face water pressure adjusting means for controlling the opening of the opening degree adjusting function valve 7 by the face water pressure gauge 13 and the mud feeding pressure manometer 12. .

Next, the control mode will be described. Mud pump p
Numeral 1 is controlled and operated by the mud-feed water pressure regulator 15 so that the water pressure upstream of the bypass circuit indicated by the mud-feed water pressure gauge 11 for maintaining the face water pressure is higher than the face water pressure, and mud feeding is performed. At this time, the opening adjustment function valve 7 of the bypass circuit 6 is opened, and when the valve 7 is opened, the pump pb is operated to prevent backflow from the sludge discharging line 5 to the sludge feeding line 4. The opening degree of the opening degree adjusting function valve 7 is controlled by the face water pressure measured by the face water pressure gauge 13 when the mud is fed to the face 2 and by the mud pressure manometer 12 during the bypass operation. In this way, the mud is fed with a margin for the flow rate of the muddy water required by the face 2, and the margin is flown to the sludge discharge line 5 through the bypass circuit 6.

Therefore, when the face water pressure decreases for some reason, the opening degree adjusting function valve 7 is throttled by the face water pressure regulator 16, the flow rate to the face 2 increases, and the water pressure is maintained. When the face water pressure increases, the opening of the opening adjustment function valve 7 is increased, and the flow rate of the bypass circuit 6 is increased.
Reduce and stabilize face water pressure. Further, the sludge flow rate is measured by the sludge flow meter 14 so that a stable sludge flow rate is obtained, and the sludge pump p2 is controlled and operated by the sludge flow rate regulator 17.

These controls are performed by each of the adjusters 15 to 17.
Can be performed manually, but each water pressure gauge / flow meter 11-
A sensor can be attached to 14 to automatically control each of the adjusters 15 to 17.

[0014]

As described above, according to the present invention, the conventional fluid circuit, which can flow only the same flow rate as one circuit from the face to the ground, is provided by providing a bypass circuit to the front of the face valve set. The flow rate of the surface can be given a margin with respect to the flow rate required at the face, and the flow rate to the face can be changed near the underground face. Therefore,
The response to the control input is improved, and the controllability is improved because the operation of the valve is faster than the increase in the rotation speed of the pump.

[Brief description of the drawings]

FIG. 1 is a fluid circuit diagram showing one embodiment of the present invention.

[Description of Signs] 1 ... Adjusting tank 2 ... Face 3 ... Treatment plant 4 ... Sludging line 5 ... Drainage line 6 ... Bypass circuit 7 ... Opening adjustment function Valve 8: Face valve set 11, 12: Sludge water pressure gauge 13: Face water pressure gauge 14: Sludge flow meter 15: Sludge water pressure regulator 16: Face water pressure regulator 17・ ・ ・ Sludging flow regulator p1 ・ ・ ・ Sludging pump p2, pe ・ ・ ・ Sludging pump pb ・ ・ ・ Pump

Claims (1)

(57) [Claims] 1. A sludge pump sends mud from a regulating tank to a face via a mud sending line, and a sludge pump pumps mud from a face through a treatment plant to a regulating tank via a mud sending line to maintain face water pressure. In the face water pressure control device in the muddy water shield construction method, a bypass circuit is provided that connects the mud pump directly after the mud pump on the face side of the mud discharge line and the mud feed line. A mud pump pressure adjusting means for disposing a function valve and controlling a mud pump by a water pressure gauge provided before a branch of a mud feed line bypass circuit;
A face water pressure adjusting means for controlling an opening adjustment function valve by a water pressure gauge provided on a face and a water pressure gauge provided on a face side of a bypass circuit branch of a mud feed line, and provided on a mud discharge pump face side of a mud discharge line. A face water pressure control device in a muddy shield method, comprising: a sludge flow rate adjusting means for controlling a sludge pump by a flow meter.