JPS6366965B2 - - Google Patents

Description

Detailed Description of the Invention The present invention is a method for hardening the soft soil in soft ground by mixing and stirring it with a hardening agent such as Beton cement so that stable ground necessary for civil engineering can be easily constructed on the soft ground. Regarding equipment.

Conventionally, in order to obtain stable ground necessary for civil engineering in ponds, lakes, rivers, ports, etc. where sludge, etc. has accumulated on the ground, the sludge above is removed from the supporting ground such as the ground, and sand or mountains are removed. It was necessary to replace it with soil, etc., which required advanced technology, difficult work, and many days, and also resulted in high costs.
There was also the problem of new pollution such as secondary pollution on land due to the large amount of sludge being shipped.

In order to efficiently harden the deep layers of soft ground made of soft soil such as sludge deposited in large quantities, a large-sized soft ground improvement device is required.

The device of the present invention has a telescoping structure in which the pedestal moves further relative to the frame in order to keep the height of the device, which increases as the size increases, to a minimum, and to facilitate the improvement of soft ground in deep layers. There is something special about what he did.

An example of implementing the present invention will be described based on the accompanying drawings.

FIG. 1 schematically shows an example of construction using the apparatus of the present invention, in which A is a front view and B is a side view of A taken along the line X--X. In this figure, 1 is supporting ground such as the underground, and the soft layer 2 in the range from the supporting ground 1 to a certain height h is fixed using a hardening agent such as Beton cement while following the unevenness of the supporting ground. It is a schematic diagram of a hardened ground 3 obtained by continuous hardening treatment over the width W.

FIG. 2 shows a hardening work vessel that is preferably used for carrying out the above-mentioned hardening process.

A is a front view, B is a side view, C is a partially enlarged detailed view of the stirring blade unit in Figure B, and D is a detailed cutaway view of the tip of the stirring blade.

Reference numeral 5 indicates a float of the work boat, which in this case is configured as a catamaran, and the upper part is for receiving the curing agent sent from land, stirring and mixing it again, and feeding it to the stirring blade means 6 described later. Agitator 7 and slurry pump 8 are installed.

In addition, 9 is these power generating devices, and Y is a winch for maneuvering a work boat.

The stirring blade means 6 is equipped with a pedestal 11, which can be raised and lowered by being guided by frames S and S' provided on the rear side, and also has a plurality of stirring blade units 10 which can be raised and lowered individually as shown in Fig. C. They are installed in parallel.

The stirring blade unit 10 is constructed such that a base plate 12 can move up and down within a pair of frames 11 and 11' having a U-shaped groove. That is, since B is attached so that the base plate 12 side can be raised and lowered by a certain distance by the operation of the winch R using the frames S and S' as guides, the above-mentioned hardening process can be carried out to a deeper layer.

In the above embodiment, the work boat is configured as a catamaran, and the frames S and S' supporting the stirring blade means 6 are provided at the stern of the ship. Alternatively, if the frame bodies S and S' are moved in the width direction of the hull, it may be a four-hulled ship. Further, the work boat may be constructed so that it can be divided and combined as appropriate in consideration of transportation, assembly, etc.

Incidentally, the stirring unit 10 may be constructed so that the base plate 12 can be moved up and down by a hoisting device, for example, a winch. In this case, mechanisms such as gears 18, 18' and racks 19, 19' are not required.

FIGS. 3 to 5 illustrate examples of work performed by the apparatus of the present invention. This will be explained below.

Figure 3 shows the state in which a waterway is constructed in soft ground. First, as shown in Figure A, a certain width t of the soft layer 2 on the supporting ground 1 is completely hardened without leaving any untreated parts. The treated portions 4 are cut and removed and piled up on both sides of the hardened ground 3 to form waterway walls.

Figure ₄ shows _the state of constructing stable ground required for civil engineering _in the sea. The hardened walls 3W ₁ , 3W ₂ , which are continuous in the length direction by being hardened by a certain height H ₁ of
3W ₃ ..., a plurality of such walls (two in the drawing) are arranged at appropriate intervals within the soft layer, and the soft layer on each wall surface is completely or partially continuous. A constant high H ₂ hardening process is performed to form a stable hardened ground 3.

To form this structure, the stirring blades a, b, c... are set to stop at the same upper limit position, and the stirring blades a, c,
e, g... are the range of H ₂ , and stirring blades b, d,
By continuously curing the range of (H ₂ + H ₁ ), a tunnel-shaped untreated portion will remain under the lower surface of H ₂ in stirring blades a, c, e, and g. can be easily obtained. On the upper surface thus obtained, necessary structures are constructed as appropriate based on the ground. This drawing shows an embankment, where p indicates foundation stones and q indicates foot protection stones.

FIG. 5 shows a case where the hardened ground 3 is structured in the shape of a grid, and on the hardened ground 3 there are
It is covered with ropes, sheet mats, etc., and is used as a foundation for foundation stones, etc. to construct embankments, roads, runways, etc. in the same manner as described above.

To form the structure, stirrers a, b, c... are set to stop at the upper limit positions, and stirrers c, f...
... are subjected to continuous hardening treatment over time, and stirring blades a, b, d, e... are subjected to continuous hardening treatment intermittently over time.
It can be easily obtained by leaving square-shaped untreated portions in portions b, d, e....

The soft ground improvement device used in the above embodiment was described as having one stage of stirring blades 6 arranged in parallel, but two or more stages of stirring blade means 6 may be arranged in series, or they may be arranged in a staggered manner for effective results. It is also possible to carry out a hardening treatment. Further, it is also free to configure it in a grid-like or other appropriate shape.

What is important in all of the embodiments described above is that the hardening treatment is performed from the bottom along the unevenness of the supporting ground, and the agitation hardening treatment parts are formed into continuous layers bonded with the same strength. It is to be hardened.

The device of the present invention performs hardening treatment by adjusting the distance between the stirring blades so that the soft soil and hardening agent are mixed together, and the stirring blades can stir from the bottom upward along the unevenness of the supporting ground. For this purpose, a method is used in which a large number of stirring blades are continuously raised and lowered individually, or a method is used in which a number of stirring blades are continuously raised and lowered while rotating in a horizontal movement state, and the stirring blades are used to follow the previous hardening process when it is in an uncured state. We solved this problem by injecting the hardening process into the preceding hardening process so that a portion of it polymerizes, and by repeating the same operation, we operated the device so that the hardening process could be performed on continuous hardened layers. This is fundamentally different from the conventional continuous wall, which is made by arranging hardened piles as close as possible in parallel to form a wall.

As described above, in the construction using the apparatus of the present invention, the soft layer is continuously hardened into a desired shape from the bottom to the top along the unevenness of the supporting ground at a constant height and width. height h
The dimensions of the width and width w are determined appropriately depending on the width of the stable ground required and the strength required, but at least in order to create stable ground necessary for civil engineering, it is necessary to A motor 13 is installed in the front of the base plate 12 so that it is guided inside the front U-shaped groove A by a guide roller provided in the
is attached, and a rotating shaft 16 for lifting and lowering is rotated via chain wheels 14 and 15. The rotation shaft 16 is supported by bearings 17, 17', and gears 18, 18' are attached to both ends thereof. 19', respectively. Reference numeral 20 denotes another motor installed on the front surface of the base plate 12, and this motor is connected to the chain wheels 21, 2.
A stirring shaft 2 passing through the base plate 12 via 1'
This is for rotating 2.

On the other hand, the stirring shaft is configured to have a hollow interior, and a stirring blade 23 having a hollow interior is attached to the lower tip to communicate with the hollow stirring shaft, as shown in Figure D. A large number of slits 24 for ejecting the curing agent are bored around the periphery.
Thus, the curing agent is fed from the slurry pump 8 through an appropriate hose (not shown) to the upper end of the stirring shaft protruding above the base plate 12, and passes through the inside of the stirring shaft to the stirring blade. Said slit 2
It is made to erupt from 4. Although not shown, the sludge hardening agent may be supplied to the stirring section through a separately provided pipe or the like. Note that 25 is an earth pressure detection device attached to the tip of the stirring blade.

The stirring blade unit 10 is constructed as described above, and when the rotation shaft 16 is rotated by the drive of the motor 13, the gears 18, 18' are engaged with the racks 19, 1.
9' and rotate the base plate 12 itself to the base 11,1.
1', and the position of the stirring blade 23 attached to the tip of the stirring shaft 22 in the soft stratum can be changed at any time. Although details will be described later, if the frames 11, 11' are guided by the frames S, S' and further raised and lowered, the range of movement of the stirring blades 23 is further expanded. However, this elevation is caused by the earth pressure detection device 25
This is done by changing the drive of the motor 13 within a certain range while detecting the earth pressure. Although this example has been described in which an earth pressure sensing device is provided at the tip of the stirring blade, it is not limited to this example, and various other means can be adopted. For example, this can be done by detecting changes in the torque experienced by the drive system based on the resistance experienced when the stirring shaft is lowered.

As described above, the stirring blade means 6 of the present device raises and lowers the stirring blades for each unit, and for example, each of the stirring blades a, b, c, d... When the rock reaches the surface, it is detected and one motor 20 is driven to rotate the stirring blades, and at the same time, the hardening agent is ejected to harden the stratum. At this time, the drive of the motor 13 is changed to reverse, and the stirring blades are raised one after another, and when they reach a certain height, they are lowered again while performing the same curing process, and this operation is repeated as the work boat advances. Therefore, a certain range above the supporting ground 1 is continuously hardened over a certain height and a certain width. Here is the base plate 12 in each unit that goes up and down.
The lower limit of is different depending on the unevenness of the supporting ground 1, but since the upper limit determines the upper surface of the hardened ground, it is preferable to keep it as constant as possible.

For this purpose, it is also possible to change the direction of rotation of the motor 13 according to changes in the numerical value indicated by the earth pressure detection device, other torque, etc., as in the case described above, but a simple method in this case is It is preferable that a limit switch is provided at a certain position within the frames 11, 11' on which the base plate 12 moves up and down, and that the limit switch is activated by coming into contact with this when the base plate rises. If the limit switch is set to the same position for each unit, all the upper surfaces of the hardened ground will be formed on the same plane, but if necessary, arbitrary height differences can be formed inward and outward. Such a hardened ground can also be easily formed by simply changing its position as appropriate. Therefore, necessary structures and buildings are installed directly or indirectly on such ground.

The above explanation is an example in which the stirring blade means, which has a large number of stirring blades arranged in one stage in parallel, is operated as the work boat moves. It is also possible to operate each stirring blade unit of the stirring blade means and repeat the operation. Alternatively, if the stirring blade unit is configured so that the stirring blade is rotated while moving up and down and also moves horizontally when the work boat is stopped, it will have the same effect as having multiple stirring blades. The same hardening treatment as described above can be carried out even with the stirring blade.

Although detailed explanation has been omitted, the stirring blade means 6 as a whole is
It is best to design it so that it shows a value of 10 or more.

Since the apparatus of the present invention is configured as an example of the apparatus described in detail above, the height of the apparatus can be reduced even if the apparatus performs a considerably deep hardening process. However, if the structure is made to expand and contract in multiple stages, the height of the device can be lowered more easily.

In addition, since the hardening process for shallow areas is performed in a contracted state, and the hardening process for deep areas is performed in an expanded state, it is best to construct the frame from a pair of members as shown in Figure 2. It has a feature that the guide can be reliably and firmly established, and that a stirring blade unit can be provided between the two members of the frame body, so that the unit can be moved back and forth between the same pair of members. Of course,
The structure of the frame body is not limited to the above-mentioned embodiments, and various embodiments may be imagined, such as a single guide column.

If the pedestal has a telescoping structure that allows it to move further relative to the frame, it is necessary to equip a long rotating shaft because the whole unit can be lowered at the same time as the stirring shaft is lowered during the curing process. The device can be compact and short, or the base plate 12 can be moved up and down after the lower end of the pedestal 11 has penetrated into the supporting ground, so the stirring blades can move up and down in a stable manner, making it safer. Moreover, it has an excellent feature of being able to perform highly accurate hardening treatment. Furthermore, if the device is transported in a reduced and short state, it will not only be more stable, but it will also be effective in avoiding obstacles.

When a rotating pile driver or the like is used as the transportation means, it can be provided with a rotating function in addition to a telescoping function.

The device of the present invention is an excellent soft ground improvement device having various features as described above, and can be effectively applied to soft ground improvement work.

[Brief explanation of drawings]

Fig. 1 schematically shows an example of construction using the device of the present invention, in which A is a front view, B is a side view taken along line X-X' of A, and Fig. 2 is a hardening treatment work ship. , where A is a front view, B is a side view,
C is a partially enlarged detailed view of the stirring blade unit in FIG. B, D is a detailed cutaway view of the tip of the stirring blade, and FIGS. 3 to 5 are schematic explanatory views showing working examples. 1... Supporting ground, 2... Soft layer, 3... Hardened ground, 4... Hardening treatment work ship, 6... Stirring blade means,
10... Stirring blade unit, 11... Frame, 12...
...base plate, S...frame body.

Claims (1)

[Claims] 1 A stirring shaft provided with stirring blades is rotatably attached to a base plate, and a hardening agent supply means is provided for supplying a slurry hardening agent to the vicinity of the stirring blade, and two or more base plates are provided. In addition to installing it so that it can be raised and lowered along a pedestal with grooved rails,
A soft ground improvement device characterized in that the pedestal is configured to be able to move up and down a certain distance with respect to a frame supporting the pedestal.