JP2002309568A - Device and method for columnar ground improvement - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the labor for waste by carrying out a process for preventing a filler from being mixed into earth discharged from an excavated hole when columnar ground improvement is carried out. SOLUTION: An excavating head 1 for use in columnar ground improvement by mixing the filler into the earth excavated from the excavated hole has excavating blades 5 provided at the lower part of an excavating rod 2, and agitating blades 7 provided above the blades, with both the excavating blades and the agitating blades fixed to the excavating head. A partition member 10 is provided above the agitating blades 7 via a cylindrical part 13. A driving force is transmitted to the partition member 10 via a pin member 18 provided at the rod 2. When the rod 2 is inverted, the driving force is not conducted. When inserted into the excavated hole to a predetermined depth, the partition member 10 is stopped and the excavated earth below the partition member is mixed with the filler to construct a column.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excavating apparatus used for columnar ground improvement work and a columnar ground improvement method using the excavating apparatus, and relates to an apparatus for treating an excavated soil so that an injection material is not mixed with the soil. And its construction method.

[0002]

2. Description of the Related Art When constructing a building on soft ground, cement, cement milk, water glass,
A method has been used in which an injection material such as a coagulant is mixed into the ground to improve the columnar ground, and the supporting ground of the building is reinforced as a columnar soil cement column. In the columnar ground improvement apparatus, a drilling member attached to the lower end of a hollow drilling rod is provided, and the injection material is injected into the soil excavated by the drilling member, and the mixture is stirred by a mixing and stirring blade disposed above the soil. Then, a column-reinforced part such as a soil cement column is constructed. In addition, when the columnar soil improvement device is used, an anti-rotation wing for preventing the soil from rotating together with the stirring blade attached to the rod is provided to assist the mixing action of the soil and the injection material. Means are also used which are arranged in a state of non-transmission and agitate the soil between the two types of wing members so that the mixing action of the injected material can be performed well.

[0003]

However, when the conventional columnar ground improvement method is used, the injected material is mixed with all of the soil in the hole excavated by the excavator, and is removed after the ground improvement work. Injected material is also mixed in the discharged soil. Since the soil mixed with the injection material cannot be left as it is, it is required to transport it to a disposal site designated as industrial waste and to perform landfill treatment. There is a problem that extra costs are required for disposal. Therefore, in order to reduce the amount of soil that has been mixed with the injection material, at the initial stage of excavation of the hole, remove the excess amount of soil in advance, and then add the injection material to the soil in the hole. However, in practice, pre-processing such as removal of the extraneous soil is performed.
There are many problems that need to be solved in the process control of construction work, and there is a concern that problems may occur in the process control.

[0004] An object of the present invention is to provide a construction method which does not require disposal of soil mixed with an injection material such as cement milk when constructing a column-improved soil cement column, and an apparatus used therefor. I have.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a columnar ground improvement apparatus, and more particularly to a drilling member provided with a drilling member at a lower end and a stirring member provided thereon, and a partitioning member provided at an upper portion at a predetermined interval with respect to a drilling rod provided with a stirring member thereon. , And the partition member is provided so as to be connected to and disconnected from the excavating rod. The partition member is configured as a substantially disk-shaped member, and the partition member is separated from the drill rod in a state where the drill head is drilled to a predetermined depth, and the drill hole is drilled using the drill member below the partition member. And the operation of mixing the injection material. Further, the drilling hole construction method of the present invention, by dividing the soil into which the injection material is not mixed by the partition member,
While constructing the excavation hole, the soil in which the injection material is not mixed can be discharged to the ground.

[0006] By using the apparatus constructed as described above, it is not necessary to dispose of the soil mixed with the injection material as industrial waste only by equipping the conventional excavating head with the partition member. It is possible to arbitrarily reuse the soil that is not used. In addition, when performing the work of constructing a drill hole, since there is no need to attach / detach an extra member to / from the drill rod, it is possible to improve the working efficiency, and it is unnecessary to dispose of the discharged soil. Since there is no need to take time, it is also possible to reduce the construction cost of the borehole.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction of a drilling head according to the present invention and a construction method using the drilling head will be described with reference to the illustrated example. The example shown in FIG. 1 shows the configuration of the excavating head 1 and, like the device used in the conventional columnar ground improvement method, extends along the strut member supported by the arm of the construction vehicle. 1 is configured as an apparatus capable of performing ground improvement while penetrating the ground. In the excavating head 1, the excavating rod 2 which is connected to driving means (not shown) and rotates at a predetermined rotational speed has a hollow arbitrary length.
An ejection hole 4 for ejecting the injection material is provided at an arbitrary position in the tip member 3 provided at the lower end of the nozzle.

A digging wing 5 provided above the tip member 3
Is provided by fixing the base portion to the excavation rod 2 by welding or the like. When the rotation direction of the excavation rod 2 is set in the arrow direction (clockwise direction) in the illustrated example, a predetermined direction is set in the rotation direction. It is provided as a member inclined in the angle descending direction. Also, a claw member 6 is provided at the tip of the excavation wing 5.
Are provided so as to protrude at predetermined intervals, and the claw member 6 is provided.
The soil excavated by... Is moved upward along the slope of the excavation wing 5. The shape of the digging wing 5 and the arrangement interval / shape of the claw members can be configured in the same manner as in the case of the conventional device. The digging wing requires particularly limited conditions. is not.

A stirring blade 7 is attached to the upper part of the excavating blade 5 at a predetermined interval. The stirring blade 7 has a base fixed to a drilling rod and has a length substantially equal to that of the excavating blade 5 And protrude from it. It is possible to arrange only one stirring blade 7 with respect to the excavation rod. However, in order to improve the mixing and stirring performance of the soil, a plurality of stirring blades 7 may be arranged at arbitrary intervals. . By rotating the excavating rod 2, an effect of disturbing the soil in the hole excavated by the excavating blade 5 with the stirring blade 7 is given. Thus, the mixing operation of the injection material can be performed by the stirring blade 7.

A partition member 10 is disposed above the stirring blade 7 at an arbitrary interval. When the excavation rod 2 is rotated in the excavation direction, the partition member 10 is rotated together with the excavation rod 2. However, when mixing the injected material into the excavated soil, the partition member 10 is configured to be released from the rotation of the excavation rod 2. The partition member 10 has a base portion attached to a cylindrical portion 13 slidable with respect to the excavating rod 2. Is provided with the engaged concave portion 15 provided with the engaged portion 16 and the inclined surface portion 17 cut in from below.

As shown in FIGS. 1 to 3, the cylindrical portion 13 is a combination of semi-cylindrical members and is fixed by a stopper 14. The inner diameter of the cylinder is equal to that of the drill rod. The cylindrical part is allowed to rotate freely along the excavating rod, with a margin slightly larger than the outer diameter. The locked portion 16 provided in the engaged concave portion 15 can lock the pin member 18 when rotating the excavation rod 2 during excavation, and the excavation rod 2 is rotated in the opposite direction. At this time, the pin member 18 is guided so as to slip out of the slope portion 17 and come out.

The partition member 10 is constructed as shown in FIGS. 2 and 3. In the example shown in the figure, two semicircular sector plate members 11 and 11a are used in combination. Are provided with downwardly inclined members 12 and 12a which are inclined downward at a predetermined angle. When the partitioning member 10 is settled in the drilling hole while rotating the drilling rod 2 in the drilling direction, the partitioning member 10 is rotated together with the drilling rod 2 so that the soil is in the hole. The partition member 10 is embedded. Further, in a state where the partition member 10 is released from the rotation of the excavation rod 2, the cylindrical portion 13 is not linked to the rotation of the excavation rod 2, but the partition member 10 is positioned at the embedded position, and the excavation head is rotated. Drilling work can be continued.

Using an apparatus using the excavating head 1,
When performing columnar ground improvement work, refer to Figs.
As shown in (a), with the partition member 10 fixed and held with respect to the excavation rod 2, the excavation rod 2 is rotated in the excavation direction so as to penetrate a position where the excavation hole 20 is to be constructed. Then, when the soil excavated by the excavation blade 5 is settled in the ground while being loosened by the stirring blade 7, the partition member 10 also enters the hole. When it is detected that the depth of the partition member 10 has reached a predetermined position while the excavating head 1 is penetrating into the ground, the excavating rod 2 is rotated in the direction opposite to the excavation, and the pin member is rotated. The member 18 is disengaged from the engaged recess 15, and the partition member 10 is released from the rotation by the pin member 18, and as shown in FIG. . Therefore, even if the excavating rod 2 is subsequently rotated in the excavating direction to mix the injected material into the excavated soil, the partition member 10 is not rotated, and the partition member 10 is independently rotated in the hole. It will be in a state of being put in.

The position where the partition member 10 is left in the hole depends on the soil properties of the ground to be excavated and the height at which the pile head is exposed, that is, the depth of the building position at the base of the building, and The position is determined as a position calculated based on the relationship with the amount of the injected injection material. For example, if the borehole diameter is 60
Assuming that 0 mm and a drilling depth of 5 m require 425 kg of a solidifying agent such as cement of the injection material and 255 liters of water, the volume of the injection material is 29.
It is 2 liters, which is about 1.4 m when converted to the height of the pillar. Therefore, the position where the partition member 10 is separated from the rotation of the excavation head and stopped is set when the partition member 10 is lowered to a depth of 1.4 m from the ground surface.
What is necessary is to release the drill rod 2 and leave it.

After excavating the excavating head 10 to a predetermined depth of the excavating hole 20 from the state shown in FIG. 4A, as shown in FIG.・ Continue the work of excavating holes and mixing and stirring the injected material with the stirring member. Then, at the lower part of the partition member 10 left at a position in the middle of the excavation hole 20, the injection material is supplied to the excavated soil, and the columnar ground improvement operation is performed by the soil 21 mixed with the injection material while mixing with the stirring blade. I do. During the ground improvement work, the amount of the soil 21 mixed with the injection material gradually increases below the partition member 10 by the injection material supplied from the ejection hole of the excavation rod 2. When the volume of the mixed soil below the partition member 10 is increased by the supply of the injection material at the portion of the excavation hole, the partition member 10 moves so as to be pushed up toward the upper portion of the hole, and moves to a predetermined depth. In the state where the excavation part has been propelled so far, the height of the partition member 10 becomes a height corresponding to the construction depth of the foundation of the building, and excess soil on the upper part of the partition member 10 is discharged to the ground.

Thereafter, the soil 21 mixed with the injection material is pressed downward by the excavating blade 5 and the stirring blade 7 by rotating the excavating rod 2 in the reverse direction. An operation of raising the excavation head 1 is performed. Then, as shown in FIG. 4C, the partition member 10 engaged with the pin member 18
Is raised with the lower member of the drilling head and can be removed from the borehole 20. The soil 22 partitioned by the partition member 10 inside the excavation hole 20 and raised and discharged together with the partition member may be left as it is because the soil is not mixed with the injection material. It is also possible to use it.

The working device equipped with the excavating head can be configured, for example, as shown in FIG.
The work vehicle 30 shown in FIG. 5 is a self-propelled vehicle generally used in the related art.
3, the guide post 35 is supported upright. A drive head 37 provided on the guide post 35 is provided so as to be able to move up and down by using a wire 34 of a winch 31 provided on a vehicle, and a drilling rod 2 attached to a lower portion is provided on the drive head 35 by a hydraulic motor or the like. Rotate using a drive mechanism. Further, the drive head is provided with a head member for supplying an injection material to an upper end portion of the drill rod 2,
The material is supplied from the injection material mixing device 38 using the supply pipe 39.

When the drilling hole 20 is constructed by using the equipment mounted on the work vehicle, the guide post 35 is positioned at the position where the drilling hole is constructed, and the drilling operation using the drilling head 1 is performed. . Then, after the excavating head 1 is combined with the partition member 10 and excavated to a predetermined depth, the partition member 10 is separated from the excavating rod 2 as shown in FIG. While lowering only the excavating / mixing members, the injection material is mixed into the excavated soil to perform columnar ground improvement work. Further, after the construction of the excavation hole, the soil discharged to the ground can be used for any purpose together with the soil excavated from the foundation of the building or the like, so that the soil is transported to a landfill as industrial waste. There is no need to throw it away. In addition, when mixing and stirring the injected material into the excavated soil, it is possible to apply a combination of a co-rotation prevention mechanism of the soil to the agitating blade, similarly to a conventionally known device of this type, it is possible to apply, A co-rotation prevention mechanism having an arbitrary configuration may be used in combination with the stirring blade.

As the work vehicle, any conventionally known device may be used, and a device capable of satisfying construction conditions such as the construction length of the excavation hole is used. Further, as the injection material mixing apparatus, an apparatus having a performance corresponding to the drilling hole construction conditions can be used. Further, the excavating head is not limited to the interlocking mechanism as shown in the drawings as long as the partitioning member can be set to a driving / non-driving state with respect to the excavating rod. The configuration of the separating means is not particularly limited to the mechanism described in the embodiment.

[0020]

According to the present invention, it is necessary to dispose the soil mixed with the injection material as industrial waste only by equipping the conventional excavating head with a partition member by using the apparatus configured as described above. Therefore, it is possible to arbitrarily reuse soil in which the injection material is not mixed. Also,
When performing the work of constructing a borehole, there is no need to attach / detach an extra member to / from the drilling rod, so it is possible to improve the work efficiency of constructing the borehole, and to dispose of the discharged soil. Since there is no need for extra work, it is possible to reduce the cost of constructing the foundation of the building together with the cost of constructing the excavation hole.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a configuration of a drilling head.

FIG. 2 is a plan view of a partition member.

FIG. 3 is a side view of a partition member.

FIGS. 4A to 4C are explanatory diagrams showing steps of a digging operation of a digging hole.

FIG. 5 is an explanatory diagram of a configuration of a working device.

[Explanation of symbols]

Reference Signs List 1 drilling head, 2 drilling rod, 3 tip member, 4 orifice, 5 drilling wing, 7 stirring blade, 10 partition member, 11 fan plate member, 1
2 downward inclined member, 13 cylindrical portion, 15 engaged concave portion, 16 locked portion, 17 slope portion, 18
Pin members, 20 drill holes, 21 mixed soil,
22 Ejected soil, 30 Work vehicle, 32
Ejected soil, 35 guide posts, 38 infused material mixing equipment.

Claims (5)

[Claims] A hollow excavation rod having an upper portion connected to a driving means and a means for supplying the mixed material, and having a lower end provided with an opening for ejecting the mixed material; a excavation member provided at a tip end of the excavation rod; A stirrer member provided at a predetermined interval above the excavation member, comprising: mixing the mixed material with the stirrer member in the soil of the pile hole excavated by the excavation member by rotating the excavation rod to improve the ground. In the device to be performed, a partition member that partitions the soil of a hole excavated at a predetermined interval above the stirring member is arranged, and in the hole excavated by the excavation member, the partition member is stopped at an arbitrary position. A column-like ground improvement apparatus, wherein the ground improvement can be performed by excavating a hole below the partition member and mixing a mixed material into the excavated soil in the state where the partition member is in the closed state. 2. A locking means for transmitting drive to a partition member is provided at a predetermined position of the excavation rod, and is rotated in a direction opposite to a direction of excavation by the excavation rod to lock the partition member. A means for canceling the drive transmission by means is provided, and in a state where the partition member is buried to a predetermined depth, the partition member is separated from the rotation of the excavation rod and stopped, whereby the soil under the partition member is removed. The columnar ground improvement device according to claim 1, wherein a process of stirring only the mixed material is performed. 3. A method according to claim 1, further comprising forming a pin member as a locking means of the partition member provided to protrude from the excavation rod, and an engaged concave portion as a locked portion provided on the partition member. In the recess, the drive transmission to the partition member is performed by the rotation of the excavation rod in the excavation direction, but the drive transmission to the partition member is released by the rotation of the excavation rod in the reverse direction. 3. The columnar ground improvement device according to 2. 4. The partition member is configured as a combination of two or more fan-shaped or semi-circular members,
At the tip of the partition member in the excavation direction of the excavation rod,
The columnar ground improvement device according to any one of claims 1 to 3, further comprising means for guiding soil upward. 5. A hollow digging rod having an upper portion connected to a driving means and a means for supplying a mixed material, and having a lower end provided with an opening for ejecting the mixed material; a digging member provided at a tip portion of the digging rod; Rotating the excavation rod using a device provided with a stirring member provided at a predetermined interval above the excavation member, and a partition member that partitions the soil of the hole excavated at a predetermined interval above the stirring member. At a predetermined position of the excavated hole excavated by the excavating member, the partition member is separated from the driving of the excavating rod and stopped, and in a state where the mixed material is not mixed into the upper soil partitioned by the partition member, A method for improving a columnar ground, comprising: mixing a mixed material while driving an excavating member and a stirring member only on soil under a partition member to excavate holes and improve a ground.