JPH0444043B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a construction method and apparatus for building a so-called soil-cement retaining wall by mixing and stirring soil in situ underground and a soil consolidation solution such as a cement solution. It is something.

[Industrial Application Fields] Soil-cement earth retaining walls are widely used, for example, as surrounding earth retaining walls when constructing basements of buildings, or as temporary earth retaining walls in conduit burying work.

[Conventional technology] The conventional soil-cement earth retaining wall construction method uses a device in which multiple vertical stirring shafts are arranged close to each other in parallel.
The cement solution is discharged from the tip of each vertical stirring shaft while the shafts are rotated in opposite directions to excavate and stir, so that soil cement is shaped so that a portion of the excavated hole formed by each vertical stirring shaft overlaps with each other. This is a multi-axis pillar column construction method for constructing earth retaining walls. (See Figure 3).

[Problem to be solved by the invention] In the conventional multi-axis column column construction method, the retaining wall width is 1 to 1.5
Since a multi-shaft excavation device with a series of 3 to 5 axes perpendicular to m is used, if the depth of the retaining wall becomes large, the weight of the device becomes excessive, and therefore the crane to suspend it is also required. It is extremely large and construction costs are high, and it is difficult to use this method on small-scale sites.

Furthermore, the constructed soil-cement earth retaining wall is constructed by rotating a series of vertical stirring shafts that are arranged in close parallel to each other so that the stirring blades of each vertical stirring shaft overlap slightly with each other. Since the earth retaining wall was stirred and mixed, the cross-sectional shape of the earth retaining wall was a circular chain shape as shown in FIG. 3, and there was a drawback that the wall thickness could not be uniform, which should be the ideal earth retaining wall.

The present invention creates a soil-cement earth retaining wall with an arbitrary wall width using a combination device of two vertical stirring shafts and a horizontal stirring shaft installed between the two shafts, This is an attempt to solve all the drawbacks of the conventional construction methods mentioned above.

[Means to solve the problem] The apparatus of the invention is shown in FIG.

The vertical stirring shafts 1, 1' are equipped with rotational force transmission boxes 4,
4' above each tip of the shaft by the same distance of an appropriate length, and around the vertical stirring shaft outside the rotational force transmission box, stirring blades 2 and 2' are installed over almost the entire length of each shaft, and A digging blade 3, 3' is fixed to each tip.

Two such vertical stirring shafts 1, 1' are arranged vertically and parallel to each other with an appropriate interval. The insides of the rotational force transmission boxes 4, 4' are symmetrical and have the same structure, and as shown in FIG.
Lower gear box 9 and solidification solution distribution chamber 10
It is composed of.

Now, if the two vertical stirring shafts 1, 1' are reversed with respect to each other by a reduction motor as in the conventional method, the rotation of the vertical stirring shafts 1, 1' will be controlled by the upper gear in the rotational force transmission box of each shaft. The upper horizontal stirring shaft,
And rotation will be given to the lower horizontal stirring shaft.

Further, a part of the solidifying solution (for example, cement solution) flowing through each of the vertical stirring shafts 1 and 1' is transferred from the solidifying solution distribution chamber 10 in the rotational force transmission box to the horizontal pipe 7 for jetting the solidifying solution. The remaining solution is ejected into the in-situ earth and sand from the ejection hole 16 of the horizontal pipe, and the remaining solution is ejected into the in-situ earth and sand from the tips of both vertical stirring shafts.

As described above, the present invention provides two vertical stirring shafts regardless of the wall width per element (generally 1 to 3 m), a horizontal stirring shaft provided between the shafts,
Since the construction is carried out using a device that combines horizontal pipes for ejecting solidified solution, the weight of the device is greatly reduced compared to the conventional multi-axis column construction method even if the wall depth becomes large. , the crane for suspending this can also be small, and construction costs are therefore low. Additionally, the small size of the crane means that it can also be used on small-scale sites.

In addition, the cross-sectional shape of the soil cement wall constructed by this device has a uniform wall thickness as shown in Figure 2, so the present invention is a construction method that can solve the various drawbacks of conventional construction methods at once. .

[Effect] This will be explained with reference to FIG.

1. The vertical stirring shafts 1, 1' of this device suspended in a predetermined position by a crane are connected to the deceleration motor 19.
At the same time, while rotating the power transmission device 20 in opposite directions, it is gradually suspended into the ground.
Start flowing the soil consolidation solution into both vertical stirring shafts.

Both vertical stirring shafts 1, 1' are provided with rotational force transmission boxes 4, 4', respectively, and their functions are exactly the same, so the vertical stirring shaft 1 side will be explained here.

2 Rotational force transmission box 4 installed on vertical stirring shaft 1
is assembled so that it can freely rotate about the axis without being subject to rotation of the axis.

3. A vertical stirring shaft passes through the rotational force transmission box 4, and the box is partitioned into an upper gearbox 8, a solidification solution distribution chamber 10, and a lower gearbox 9.

4 The rotational force of the vertical stirring shaft 1 is transmitted to the upper horizontal stirring shaft 5 by the bevel gears 11 and 12 in the upper gear box 8, but the rotational force of the vertical stirring shaft 1' is also synchronized with the vertical stirring shaft 1. and
It is transmitted to the horizontal stirring shaft 5 by a similar transmission mechanism.

5. The lower horizontal stirring shaft 6 also receives rotational force in the same manner as the upper horizontal stirring shaft.

6 In the rotational force transmission box, there is a solidification solution distribution chamber 10, and the vertical stirring shaft 1 passing through the chamber has a solidification solution branching hole 15, and the solution is transferred to a horizontal pipe for jetting the solidification solution. 7 and is ejected from the ejection hole 16 of the horizontal pipe 7 into the earth and sand at the original location.

7. A part of the solution in the vertical stirring shaft 1' is also introduced into the horizontal spouting pipe 7 by a similar mechanism.

8. Other solutions are ejected from the tips of both vertical stirring shafts 1, 1' into the soil at the original location.

9 As explained above, this method involves the rotation of both vertical stirring shafts and the solidified solution spouted from the tips of the shafts. A soil-cement earth retaining wall with uniform wall thickness is constructed by the action of

[Example] 1 As shown in FIGS. 4 and 5, the present device is attached to the crane mast 17. A deceleration motor 19 and an attached power transmission device 20 are integrally suspended from the top of the leader 18 of the crane mast so that they can slide along the leader, but this is the same device as in the conventional construction method. It is.

2. Assemble this device, place the cutting blades 3, 3' at the tips of the vertical stirring shafts in the predetermined positions, and start mutually counter-rotating both the vertical stirring shafts 1, 1'. At the same time, the horizontal stirring shafts 5, 6 will also rotate. Start mutually counter-rotating.

3 When the excavation blades 3 and 3' have excavated approximately 1 to 2 meters into the soil, a soil consolidation solution (e.g., cement solution) is introduced into both vertical stirring shafts 1 and 1' from a separate mixing plant using a hose. This equipment is the same as the conventional method.

4 The cement solution flowing into both vertical stirring shafts is
It is ejected from the lower end, and is also ejected into the soil from the ejection hole of the horizontal pipe 7 for ejecting the solidification solution, and is stirred and mixed with excavated and crushed earth and sand by the rotation of both vertical stirring shafts and both horizontal stirring shafts, so-called. It becomes soil cement.

5. While sequentially lowering the device into the soil, once it reaches a certain depth, it is also possible to move the device up and down over a certain range to further ensure sufficient stirring and mixing.

6 When the construction of one element is completed in this way, the device is moved so that one vertical stirring shaft wraps around the existing element, and the adjacent elements are constructed in the same manner, repeating sequentially until the specified A retaining wall length will be constructed.

[Effects of the Invention] As described above, the present invention differs from the conventional multi-shaft column row construction method in which a large number of vertical stirring shafts are arranged in parallel and these are rotated to stir and mix cement solution and earth and sand. Unlike conventional methods, soil and cement solution are mixed by mutually counter-rotating two vertical stirring shafts and a horizontal stirring shaft between them.1. It is efficient and can shorten construction time.

2. The finished wall thickness is uniform, which prevents water leakage.

3. Compared to the construction machine of the conventional multi-axis column construction method, the device of the present invention is lighter, so the crane can be smaller, and therefore the construction cost is not only lower, but also improved in terms of site safety management. It will be advantageous.

4. Since the soil consolidation solution is ejected not only from the tips of the vertical stirring shafts at both ends, but also from the horizontal pipe for spouting the consolidation solution, it is possible to mix high-quality soil cement over the entire construction width.

5. At sites where the construction depth is shallow, the upper horizontal stirring shaft 5 shown in FIG. 1 can be omitted to further reduce the weight of the machine.

[Brief explanation of drawings]

Fig. 1: A diagram of the power transmission system of this device; Fig. 2: A cross-sectional diagram of the soil cement wall created by this device; Fig. 3: A diagram of the soil cement wall constructed using the conventional multi-axis column column construction method. Reference diagram of cross-sectional shape of soil cement wall,
FIG. 4 is a side view of the device set at the front of the crane, and FIG. 5 is a front view of the device set at the front of the crane. 1, 1 is a vertical stirring shaft, 2, 2' is a stirring blade, 3,
3' is a drilling blade, 4 and 4' are rotational force transmission boxes, 5 is an upper horizontal stirring shaft, 6 is a lower horizontal stirring shaft, 7 is a horizontal pipe for jetting solidified solution, 8 is an upper gear box, and 9 is a lower gear. box, 10 is a solidification solution distribution chamber, 1
1 and 12 are bevel gears in the upper gear box, 13 and 14 are bevel gears in the lower gear box, 15 is a branching hole for solidifying solution, 16 is a spout hole of a horizontal pipe for spouting solidifying solution, 17 is a crane mast, 18 is the mast leader, 19 is the reduction motor, and 20 is the power transmission device for the vertical stirring shaft.

Claims (1)

[Scope of Claims] 1 Two vertical stirring shafts are arranged upright in parallel with an appropriate interval, and these vertical stirring shafts are given opposite rotations to excavate and stir underground, and both The soil between the excavation holes is excavated and agitated by the rotation and descent of a single or multiple horizontal agitation shafts that span between both vertical agitation shafts, and at the same time, the soil consolidation solution is pumped through both vertical agitation shafts. Spouting it into the earth and sand from the tip of the shaft and each spout hole of a horizontal pipe for spouting solidified solution connected between the two shafts,
An earth retaining wall construction method in which the solution and excavated earth and sand are mixed by rotation of vertical and horizontal stirring shafts, and an earth retaining wall is constructed by solidifying the mixture. 2. Two vertical stirring shafts that rotate in opposite directions are arranged upright in parallel with an appropriate distance between them, and a horizontal stirring shaft and a horizontal tube for jetting solidified solution are appropriately connected between the vertical stirring shafts. The earth retaining wall construction device according to claim 1, wherein the earth retaining wall construction device is arranged.