JPS599699B2 - An underground excavation method that enlarges and shapes the lower part of the trench. - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an underground excavation method for shaping an oblique excavation wall surface.

Underground excavation methods are well known in the art.

This underground excavation method is a method of excavating a space of the desired shape and depth underground using rectangular or circular units, but all walls excavated by this force method are vertical.

For this reason, when excavating underground before constructing an underground structure, the width of the top of the ground surface and the bottom of the underground excavation are the same, so it is necessary to ensure the supporting capacity of the structure. In many cases, the width of the bottom required for this becomes the width of the top, which increases both the amount of work and construction cost, making it uneconomical.

An object of the present invention is to provide an underground excavation method that eliminates the drawbacks of the prior art described above.

That is, according to the underground excavation method of enlarging and shaping the lower excavated part of a trench according to the present invention, by excavating a width wider than the trench width at the top at an arbitrary position underground, planning and design can be performed. Therefore, it is possible to accurately excavate a space underground that matches the required shape and dimensions.

As a result, there is an advantage that the minimum required underground structure can be constructed rationally and economically.

Hereinafter, the underground excavation method according to the present invention will be explained in detail with reference to the drawings.

Figures 1 to 4 illustrate an embodiment of the earth and sand excavation device used to carry out the present invention, in which a wall-shaped groove is excavated by filling the groove with liquid such as muddy water in advance. This is an earth and sand excavation device for shaping and enlarging one side of the lower excavation part of the excavation section so that it has an even more oblique excavation wall surface.

That is, this device has a frame 2 on one side, on which an appropriate number of rotary bits 1 are attached as soil scraping tools at appropriate positions to match the shape of the diagonal excavation wall surface, and a frame 20 on the other side. In order to balance the force and the entire device, a reaction force receiving frame/balancing case 3 is connected to a hanging frame 5 via a pin 4.
The jack 6 is provided to be suspended from the suspension frame 5 and lifts up the frame 2 and the reaction force receiving frame/balance case 3 by taking a reaction force particularly at the lower part of the hanging frame 5.

Further, this rotary bit 1 is rotated by an appropriate number of motors 7 via a deceleration/rotation mechanism built into the frame 2.

An air lift 8 is disposed on the hanging frame 5 for discharging the earth and sand scraped by the rotary bit 1 and liquid such as muddy water in the groove to the ground outside the groove.

The earth and sand excavator shown in FIGS. 1 to 4 is operated as follows to perform underground excavation to form an oblique excavation wall surface.

First, the procedure for excavating the lower enlarged portion 10 of the groove 9, which has been excavated by filling the groove with liquid such as mud water, as shown in FIGS. 5 and 6, will be explained.

Fig. 7 shows a rotary bit 1 attached to the frame 2 of the earth and sand excavator, which is rotated, and the center of the hanging frame 5 is aligned with the center line 11 of the lower part of the groove 9 that has already been excavated, and the hanging frame 5 is gently lowered. Then, operate the jack 6 slightly to press the reaction force receiving frame/balance case 3 against the earth and sand wall surface 12 on the opposite side of the planned excavation area, and at the same time, move the frame 2 with the rotary bit 1 attached to the wall surface of the planned excavation area 10. It shows the pressed state.

From this state, by rotating the rotary bit 1 and gradually pushing the frame 2 into the earth and sand by operating the jack 6, the rotary bit 1 scrapes away the earth and sand at the planned excavation location 10, and the frame is opened. It accumulates on the trench bottom from the hole 13 and below the earth and sand excavator.

This accumulation. The object 14 is discharged out of the groove by the air lift 8 together with liquid such as muddy water in the groove.

If this operation is continued and the frame 2 is pushed out to a predetermined position by the operation of the jack 6, the parts 15 that cannot be directly scraped off by the rotary bit 1 will be removed with a somewhat unshaped 4.
As it is, the predetermined lower enlarged portion 10 excavation is generally formed.

This state is shown in FIG. Next, if the entire earth and sand excavator is pulled upward little by little as shown in FIG. 9 in this state, the middle part will have the same excavation width as the enlarged lower part 10 as shown in FIG. The enlarged portion 16 up to is generally formed.

After the enlarged portion 17 shown in FIG. 6 is formed by such a procedure, the entire excavation equipment is moved laterally to the position of the excavation portion 18 shown in FIG. 6, and excavation work is carried out in the same manner as described above. , except for the portion 15 which cannot be completely covered by the rotary bit 1, the excavation enlarged portion 18 is further enlarged and generally formed.

After completing the above operations, as shown in Figure 9, if you move the entire earth and sand excavation device in the horizontal direction with 1 while placing it on the diagonal operation wall, the rotary bit 1 will be installed by shifting it up and down little by little. (as shown in FIG. 3), the portion 15 remaining during the excavation is also scraped off, and not only the oblique excavated wall surface but also other wall surfaces can be shaped into a predetermined shape.

In addition, by raising and lowering the earth and sand excavation equipment little by little, the sixth
The side excavated wall surface 19 shown in the figure can also be shaped into a substantially wall shape.

By repeating the above-mentioned procedure repeatedly and excavating as needed, a space with an arbitrary height and a wall widened on one side compared to the trench width at the top can be created underground. It is possible to reliably print in the position of

Note that the configuration of the earth and sand excavation device described above is not limited to that described above.

For example, instead of the rotary type, a reciprocating type, endless type, or spiral type scraping tool may be used, and the shape of the device can be freely selected depending on the shape of the planned excavation.

Further, the shape to be excavated and formed by the underground excavation method of the present invention for forming this oblique excavation wall surface is not limited to the above-mentioned one.

For example, various excavation cross-sectional shapes as shown in FIG.

Also, as shown in Figs. 11 and 12, excavation is performed below the cross-buried structure 20 encountered during the process of constructing an underground continuous wall, and below the shoe opening 21 in an open caisson as shown in Figs. 13 and 14. By applying the method of the present invention to the excavation of

In this case, 22 in FIGS. 11 and 12 is a guide column, 2
3 is an air lift.

Up until now, it has been assumed that the diagonal excavation wall remains stable after excavation, but in reality, depending on the nature of the soil and other conditions, it may be difficult to maintain stability in the excavation trench after diagonal excavation. There are many cases where it is difficult for the wall to remain stable until reinforcing cages are inserted and concrete is placed, and there is a risk that the wall will collapse.

In such a case, prior to excavation to form the diagonal excavated wall, a soil consolidating material or the like is poured in advance into the earth and sand 10 (shown in Figure 7) at the location to be excavated so that there is no risk of the wall collapsing even after excavation. Therefore, it is essential to improve the properties of the soil.

In order to ensure that this condition is met, an underground excavation method will be described in which an earth and sand consolidating material is injected into the planned earth and sand excavation location 10 directly from within the trench.

Figures 15 to 18 illustrate an embodiment of the earth and sand consolidation material injection device used to carry out the present invention. This device aims to improve the properties of the earth and sand by injecting earth and sand consolidation material into the planned excavation location 10 on one side of the lower part of the trench.

That is, this earth and sand consolidating material injection device has on one side a plate 32 which also serves as a pouring material outflow prevention plate to which an appropriate number of injection pipes 31 having an appropriate number of injection holes 30 for injecting the consolidating material into the earth and sand are attached.
On the opposite side, a reaction force receiver/balance frame 33 for balancing the reaction force of the plate 32 and the entire device is suspended from the hanging frame 35 via a hanging tool 34, and a reaction force is taken at the lower part of the hanging frame 35. The jacks 36 and 9 are configured to push out the plate 32 and the reaction force receiver/harance frame 33, respectively.

This injection pipe 31 is connected to the injection material surging container 38 installed on the hanging frame through a hose etc. 37, and the injection material supplied from the ground, etc. outside the trench is smoothly and appropriately ejected into the earth and sand. It has functions.

The earth and sand consolidating material injection device shown in FIGS. 15 to 18 is operated as follows to inject the consolidating material into the planned excavation location 10 where an oblique excavation wall surface is to be formed.

First, the procedure for injection into the lower enlarged portion 10 shown in FIG. 5 will be explained.

As shown in Fig. 19, the earth and sand consolidation material injection device is gently lowered by aligning the center of the hanging frame 35 with the center line 11 of the lower part of the groove 9 that has already been excavated, and the jack 36 for the reaction force receiver/balance frame 33 is activated. Then move the frame to the planned excavation location 100 and the earth and sand wall 1 on the opposite side.
2, then press the injection material outflow prevention plate 32.
By operating the jack 36, the plate is pressed until it comes into close contact with the groove wall surface of the area 10 to be excavated, and the injection pipe 31 is inserted into the area 1 to be excavated by the length that protrudes from the plate 32.
This shows the state of being press-fitted into the earth and sand of 0.

While maintaining this state, pour the injection material into the injection hole 30 of the injection pipe 31.
Plate 3 that also serves to prevent the injection material from flowing out if it erupts into the soil.
Combined with the effect of 2, it is possible to effectively inject into the planned injection range 39 centered on the planned excavation location 10.

This state is shown in FIGS. 19 and 20. By injecting the soil consolidation material through these steps, the properties of the soil around the planned excavation location 10 will be improved so that it will be stable even when an slanted excavation wall surface is formed, so this will be successively applied to the locations deemed necessary. On the other hand, the earth and sand can be improved appropriately in any soil condition and at any position, and it is possible to form a diagonal excavated wall surface in a stable state.

So far, we have been talking about one side of the groove, but it goes without saying that it can be done on both sides of the groove at the same time just as well as on one side.

As described above in detail in accordance with each condition, according to the underground excavation method of the present invention, even if the properties of the soil constituting the wall surface of an already excavated trench etc. vary, the above-ground part of the trench can be Since it is possible to reliably excavate a space with a diagonal excavation wall surface wider than the width of the slanted excavation wall at any position underground, it will open up a new field in future underground excavation methods, and will lead to the development of underground trench structures. We are confident that this will make a significant contribution to the construction sector.

[Brief explanation of drawings]

Fig. 1 is a side view showing one embodiment of the earth and sand excavation device according to the present invention, Fig. 2 is a plan view, Fig. 3 is a front view, and Fig. 4 is a view taken along line I-I in Fig. 2. Figure 5 is a cross-sectional view showing the trench that has already been excavated and the area to be expanded, Figure 6 is its plan view, and Figure 7 is the lower part of the trench that has already been excavated using the earth and sand excavator. Fig. 8 is a side view showing the frame and balance frame pressed against the walls on both sides of the hanging groove; Figure 10 is a sectional view illustrating the shape that can be excavated and shaped by the method according to the present invention, and Figure 11 is a continuous underground wall formed by the method according to the present invention. A plan view showing the excavation method under the cross-sectional buried object during construction, Figure 12 is the same as ■- in Figure 11.
■A vertical cross-sectional view along the line, Figure 13 is a plan view showing the excavation procedure below the shoe blade of the open caisson, and Figure 14 is the first
FIG. 15 is a side view showing one embodiment of the earth and sand consolidation material injection device according to the present invention, and FIG.
Figure 6 is a plan view, Figure 17 is a vertical cross-sectional view taken along line v-v in Figure 15, Figure 18 is a cross-sectional view taken along line EV-IV in Figure 15, and Figure 19 is a soil consolidation view. The material injection device is hung at the bottom of the trench that has already been excavated, the plate is pressed against the wall of the intended injection site on one side of the trench, the injection pipe is press-fitted, and the balance frame is pressed against the wall on the other side to inject the material. FIG. 20 is a side view showing the state in which it is present, and FIG. 20 is a front view thereof. 1...Rotary bit, 2...Frame, 3...
Reaction force receiver/balance case, 4... pin, 5... support frame, 6... jack, 7... motor, 8... air lift, 9... already excavated groove, 10... ... lower enlarged part, 11 ... center line of the trench, 12 ... earth and sand wall surface on the opposite side of the planned excavation location, 13 ... hole in frame 2,
14... Excavated deposit, 15... Location that cannot be scraped directly with a rotary bit, 16... Enlarged part in the middle, 17... Enlarged part, 18... Enlarged part, 19...
・Side excavated wall surface, 20...Cross buried objects, 21...
- Shoe blade opening, 22... Guide post, 23... Air lift, 30... Injection hole, 31... Injection pipe, 32
... Injection material pouring prevention plate, 33 ... Reaction force receiver and balance frame, 34 ... Hanging tool, 35 ... Hanging frame, 3
6... Jack, 3T... Hose, etc., 38... Injection material surging container, 39... Scheduled injection range.

Claims (1)

[Scope of Claims] 1. In a trench that has been excavated in the form of a wall by filling the trench with liquid such as muddy water, a frame with an earth and sand scraping tool installed in the trench, and a frame on the opposite side of the frame. A reaction force receiving frame and a balancing case for balancing the reaction force and the entire device are hung neatly via pins, and a jack is used to push up the frame and the case, respectively, and the scraped earth and sand are removed from the liquid. An earth and sand excavator equipped with an airlift and an air lift for discharging to the ground is lowered, the jack is operated to press the case against the earth and sand wall on the opposite side of the area to be excavated, and the frame is moved to the area to be excavated. enlarging the lower excavated part of the trench, characterized in that the excavated part is enlarged on one or both sides of the lower part of the trench by gradually pushing it into the earth and sand and scraping off the earth and sand with the earth scraping tool. An underground excavation method for modeling. 2. The lower excavation portion of the trench according to claim 1, wherein the earth and sand excavation device that has descended into the trench is pulled upward or moved laterally by t, -tU to further enlarge the excavation portion. An underground excavation method that enlarges and shapes. 3. A patent characterized in that when the wall surface to be expanded by the above-mentioned excavation method is unstable and there is a risk of landslide, an earth and sand consolidation material is injected into the above-mentioned area in advance, and then the lower part of the above-mentioned trench is excavated. An underground excavation method for enlarging and shaping a lower excavated portion of a trench according to claim 1 or 2.