JP2737826B2 - Face-limited underground wall excavator - 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-limited underground continuous wall excavator.

[0002]

2. Description of the Related Art Underground continuous wall construction involves exchanging a stabilizing liquid while excavating a trench to be a wall, and after digging, constructing a reinforcing steel cage or the like and pouring concrete, forming a wall body, and forming a continuous wall. It is construction to be done. At this time, in order to excavate the ground without independence deeply, the stabilizing liquid: (1) forms a protective film on the excavated surface to prevent the ground from collapsing.

(2) Prevent the flow of groundwater.

(3) To prevent water loss and secure a water pressure corresponding to the earth pressure.

(4) The excavated surface is kept stable for a long time.

Such performance is required. For this purpose, the stabilizer maintains the specific gravity, viscosity, drainage amount, sand distribution, PH, etc. at necessary control values.

[0007] Excavation methods are broadly classified into clamshell bucket methods and rotary excavation methods. The clamshell bucket method is not often used for deep-sealed ones, because the groove wall may be easily damaged when discharging the soil. On the other hand, the stabilizing liquid of the rotary drilling method has a function as a mother liquor for transporting the drilling waste in slurry, in addition to stabilizing the groove wall, and a solid-liquid separation device is incorporated in the slurry discharge part.

[0008]

The conventional method has the following problems.

(1) When excavating with a rotary excavator, the specific gravity of the stable liquid increases due to the stirring and mixing action of the slurry and the muddy water, and the resistance (head) at the time of slurry transportation increases, and solid-liquid separation occurs. Later, when circulated in the groove wall and stored,
The amount of slime increases and the mud film attached to the wall becomes thicker.

(2) The stabilizer is degraded by alkali ions in the soil and the like, and needs to be replaced with a new stabilizer.

(3) During the solid-liquid separation, the stable liquid is discharged by adhering to the debris.

(4) Fine particles in the stable liquid are retained in the liquid, and solid-liquid separation is difficult.

(5) According to the above (1) to (4), strict control of a stable liquid and a large-capacity solid-liquid separator are required to ensure quality.

An object of the present invention is to provide a face-limited underground continuous wall excavator which facilitates stable liquid management and reduces the capacity of a solid-liquid separator.

[0015]

According to the present invention, there is provided a partition wall for defining a face portion of an excavator from a groove wall above the face portion, a stable liquid supply line for supplying a stable liquid to the groove wall portion, and A stable liquid supply control device, a water supply line for supplying fresh water to the face portion and a water supply amount control device, a drain line for discharging the drilling debris of the face portion using clear water as mother liquor, and a drilling debris for the drain line from fresh water. A solid-liquid separation device for separating, and keeping the pressure of the face and the groove wall constant, and
A control panel is provided for adjusting the fresh water supply amount so that the value obtained by subtracting the stable liquid replenishment amount from the drain water amount does not greatly differ from the fresh water supply amount.

[0016]

In the above-structured underground wall excavator with limited face, the face is connected to the ground by a water supply line and a drainage line, and a stable liquid is stored in the groove wall.

[0017] Therefore, excavation slips at the face portion,
By making the slurry circulation using fresh water as the mother liquor, the management of the slurry mother liquor becomes only the specific gravity management according to the performance of the slurry pump, and for the mother liquor that adheres to the slip and is discharged, it is only necessary to supply fresh water. Get better.

Further, the stable liquid stored in the groove wall has little change in specific gravity and the like because there is no agitation and mixing of debris due to transportation of the slurry.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

A pair of cutters 3 are provided on the bottom of the main body 2 of the rotary excavator 1, and a cutter driving unit 4 is provided on the upper surface of the main body 2. And 4 at the bottom of the body 2
Around the circumference, partition seal materials 5 are provided in three stages.

Referring also to FIG. 2 and FIG.
Is formed, for example, of a sheet-like body made of a filter fiber, a rubber plate, a vinyl sheet, or a composite thereof. The partition wall sealing material 5 is slidably supported by upper and lower slide guides 6 formed horizontally on the main body 2, and is provided with a groove wall a by a storage cylinder 7.
Is selectively contacted.

FIGS. 4 and 5 show another embodiment of the partition wall sealing material. The partition wall sealing material 5a is vertically pivotally attached to the step 2b formed on the main body 2a, and is selectively rotated by the undulating cylinder 7a. This is an example of contacting the groove wall a.

In FIGS. 6 and 7, the connecting wall groove A excavated by the rotary excavator 1 is connected to the upper groove wall portion A1 by a partition wall sealing material 5 connected from the main body 2 to the groove wall a. A lower face A2 is defined.

The stable liquid C in the stable liquid tank B1 is provided on the groove wall A1.
1 is provided, and the line L1 is provided with a stable liquid supply pump P1, a stable liquid supply control device D1, and a flow meter M1. The control device D1 is provided with a bypass flow rate adjusting valve V1 and an electric on-off valve V2, and an outflow-side electric on-off valve V3. The symbol S1 is a liquid level meter.

On the other hand, the fresh water C2 in the circulation tank B2 is
A water supply line L2 for circulating and supplying water, and a drainage line L3 for discharging drilling waste using the fresh water as a mother liquor are provided.

In the water supply line L2, a submersible sand pump type circulation pump P2, a water supply amount control device D2,
A flow meter M2 and a water supply pipe 10 are provided. The control device D2 is provided with a bypass-side motorized on-off valve V5 and a flow regulating valve V, and an outflow-side motorized on-off valve V4. On the other hand, the drainage line L3 is provided with a drainage pump P3, a drainage pipe 11, a flow meter M3, and a solid-liquid separation device 12. Further, pressure gauges S2 and S3 are provided on the groove wall portion A1 and the face portion A2, respectively. And the member M
1 to M3, P1, P2, S1 to S3 and V1 to V6
Each is connected to the control panel D3. In addition,
In the drawing, reference numeral L4 is a makeup water line, P4 is a cyclone driving pump, 13 is a cyclone, 14 is a drilling slip pit, 2
0 is an excavator base machine and 21 is a running block.

Next, the operation will be described.

The stable liquid replenishment control device D1 comprises:
The opening of the bypass-side flow control valve V1 is adjusted so that the level of the stable liquid C1 in the groove wall A1 is constant.

Further, the water supply amount control device D2 adjusts the opening degree of the flow control valve V6 on the bypass side to adjust the water supply amount.

The control panel D3 includes a pressure sensor S
3. Based on the detection signal from S2, the value obtained by subtracting the stable liquid supply amount from the drainage amount is such that the pressure inside and outside the face portion A2 is constant based on the detection signal from S2, and the value greatly separated from the water supply amount to the face portion A2. So that it does not become unstable.
The amount of water supply to the face A2 is adjusted by adjusting the opening of the flow control valve V1 and adjusting the bypass flow rate of the stabilizing liquid.

Therefore, the fresh water C2 circulates in the face A2, and the stable liquid C1 is stored at a constant level in the groove wall A1.

Further, by circulating the drilling debris with the mother liquor of the fresh water C2 at the face A2, the management of the mother liquor becomes only the specific gravity management according to the performance of the circulation pump P2, and the mother liquor adhered to and discharged from the debris. Again, it is only necessary to supply fresh water C2.

Further, there is no influence of alkali ions such as cement contained in the excavated soil due to ground improvement or the like.

Further, the stable liquid C stored in the groove wall portion A1
No. 1 requires quality control, but changes in specific gravity and the like are small since there is no agitation and mixing of debris due to slurry transportation.

Further, since alkali ions and the like contained in the soil only statically contact the groove wall a, deterioration is small.

Further, by the slurry transportation by the circulation of the waste water, the solid-liquid separation becomes easier than using the stable liquid as the mother liquor, and the capacity of the solid-liquid separator 12 can be reduced.

[0037]

Since the present invention is constructed as described above, the slurry is transported between the face other than the groove wall for holding the groove wall with the stabilizing liquid and the solid-liquid separating section by the fresh water circulation. In addition to facilitating stable liquid management, the capacity of the solid-liquid separator can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a main part of an embodiment of the present invention.

FIG. 2 is a side sectional view showing one embodiment of a partition wall sealing material.

FIG. 3 is a side view showing a state at the time of sealing in FIG. 2;

FIG. 4 is a side view showing another embodiment of the partition wall sealing material.

FIG. 5 is a side view showing a state at the time of sealing in FIG. 4;

FIG. 6 is an overall configuration diagram showing one embodiment of the present invention.

FIG. 7 is a liquid and electric circuit diagram of FIG. 6;

[Explanation of symbols]

 A: continuous wall groove A1: groove wall portion A2: face portion a: groove wall B1: stable liquid tank B2: circulating tank C1: stable liquid C2: clear water D1: Stabilizing liquid replenishment control device D2: Fresh water control device D3: Control panel L1: Stable liquid replenishing line L2: Water supply line L3: Drainage line L4: Makeup water line M1 ... M3 ... Flow meter P1 ... Stable liquid supply pump P2 ... Circulation pump P3 ... Sludge pump P4 ... Cyclone driving pump S1 ... Level gauge S2, S3 ... Pressure Total V1, V6: Flow control valve V2 to V5: Electric on-off valve 1: Rotary excavator 2: Body 3: Cutter 4: Cutter drive unit 5, 5a Partition wall sealing material 6 Slide guide 7 Storage cylinder 7a ··· Undulating cylinder 10 ··· Water supply pipe 11 · · · Drainage pipe 12 · · · Solid-liquid separation device 13 · · · Cyclone 20 · · · Excavator base machine 21 · · · Running block

Claims (1)

(57) [Claims] 1. A partition that defines a face of an excavator from a groove wall above the face, a stable liquid supply line for supplying a stable liquid to the groove wall, a stable liquid supply control device, and the face. A water supply line and a water supply amount control device for supplying fresh water to the drainage line, a drainage line for discharging the drilling debris of the face portion using fresh water as a mother liquor, a solid-liquid separation device for separating the drilling debris of the drainage line from freshwater, and the face. And a control panel that adjusts the fresh water supply so that the value obtained by subtracting the stable liquid supply from the drainage does not differ greatly from the fresh water supply. A face-limited underground wall excavator characterized by the following features.