JP7338009B2 - soil improvement equipment - Google Patents

Description

TECHNICAL FIELD The present invention relates to a ground improvement device used in a ground improvement method using a solidification material.

An excavation shaft in which an inner shaft and an outer shaft are formed as inner and outer double shafts, and both the inner and outer shafts are rotatable in opposite directions, and an inner stirring blade and an outer stirring blade are attached to the drilling shaft. There has been proposed a soil improvement device comprising a relative stirring impeller attached to relatively reversely rotate at the inner and outer positions (see, for example, Patent Document 1). Both ends of the inner stirring blade and the outer stirring blade are attached to the excavation shaft, and the intermediate portion is formed in an arc shape that bulges outward. A solidifying material discharging part for discharging solidifying material is provided, and the solidifying material discharging part is provided with a solidifying material discharging hole extending in the vertical direction.

Japanese Patent No. 3739620

However, in the mixed stirring region adjacent to each of the inner stirring blade and the outer stirring blade, including the region sandwiched between the inner stirring blade and the outer stirring blade, the inner stirring blade or the outer stirring blade adheres to the soil to be improved There was a possibility that a co-rotating phenomenon that rotates together with the

Therefore, an object of the present invention is to provide a ground improvement apparatus capable of reducing the possibility of occurrence of a co-rotation phenomenon in a mixing and stirring area when soil to be improved is mixed and stirred by a pair of stirring members.

The ground improvement device of the present invention is
A cylindrical inner rotating shaft member and a cylindrical outer rotating shaft member surrounding the inner rotating shaft member over the entire circumference with the inner rotating shaft member partially protruding downward are rotated around their respective axes. by rotating them in mutually opposite directions, the portion of the inner rotating shaft member protruding from the outer rotating shaft member and the outer rotating shaft member are fixed so as to protrude in the radial direction thereof. A soil improvement device configured to mix and agitate soil to be improved and a solidification material by a pair of agitating members,
radially extending from the inner rotating shaft member and the outer rotating shaft member so as to be interposed between the pair of stirring members, and rotating around the axis with respect to each of the inner rotating shaft member and the outer rotating shaft member; A shearing assisting member rotatably provided in the
In the ground improvement device having the above configuration,
At least one stirring member of the pair of stirring members extends from at least one of the portion of the inner rotating shaft member protruding from the outer rotating shaft member and the outer rotating shaft member in the radial direction thereof. , and extends obliquely upward or obliquely downward .
In the ground improvement device according to claim 1,
Preferably, the auxiliary shearing member projects obliquely upward or downward with respect to the radial direction while projecting in the radial direction of the inner rotary shaft member and the outer rotary shaft member.
In the ground improvement device having the above configuration,
Each of the pair of stirring members extends obliquely downward with respect to the radial direction from each of the portion of the inner rotating shaft member protruding from the outer rotating shaft member and the outer rotating shaft member. extend,
It is preferable that the auxiliary shearing member protrude in the radial direction of the inner rotary shaft member and the outer rotary shaft member and extend obliquely downward with respect to the radial direction.

According to the soil improvement device having this configuration, as the fluidity of the soil to be improved in the region sandwiched between the pair of stirring members decreases, the soil flows or moves so as to be dragged by the pair of stirring members. The amount of soil to be improved will increase. For this reason, the auxiliary shearing member rotates about the axis in a direction in which it is dragged relatively strongly so as to be caught in the soil to be improved that is flowing or moving so as to be dragged by each of the pair of stirring members. As a result, the shearing force is applied from the shear auxiliary member to the soil to be improved in the area sandwiched between the pair of stirring members, improving the fluidity of the soil to be improved and, in turn, reducing the possibility of co-rotation. is planned.

In the ground improvement device having the above configuration,
It is preferable that the auxiliary shearing member protrudes in the radial direction of the inner rotary shaft member and the outer rotary shaft member by an amount of protrusion larger than that of at least one of the pair of stirring members.

According to the soil improvement device having this configuration, the shear assisting member is present on the side of at least one of the stirring members with respect to the distal portion that protrudes in the radial direction compared to at least one of the stirring members. Locking soil pressure of the soil to be improved can be applied. As a result, when the auxiliary shearing member rotates around the axis so as to be caught in the soil to be improved that is flowing or moving so as to be dragged by the pair of stirring members, the area sandwiched by the pair of stirring members A shearing force is applied to the soil to be improved from the auxiliary shearing member including the distal portion, thereby improving the fluidity of the soil to be improved and, in turn, reducing the possibility of occurrence of the co-rotation phenomenon.

In the ground improvement device having the above configuration,
As the auxiliary shearing member, a plurality of auxiliary shearing members projecting in the radial direction of the inner rotating shaft member and the outer rotating shaft member are provided, and the plurality of auxiliary shearing members have rotational symmetry about the axis. It is preferably arranged so as not to

According to the soil improvement device having this configuration, the force acting on the shear auxiliary member from the soil to be improved that is flowing or moving so as to be dragged by each of the pair of stirring members is applied in the at least two directions (or range of directions). can be differentiated. As a result, it is possible to solve the situation where the force received by the soil to be improved from the soil to be improved is applied to the auxiliary shearing member and the rotation of the auxiliary shearing member about its axis is stagnant. For this reason, when the auxiliary shearing member rotates around the axis, the auxiliary shearing member exerts a shearing force on the soil to be improved in the region sandwiched between the pair of agitating members, thereby increasing the fluidity of the soil to be improved. is improved, and the possibility of occurrence of the co-rotation phenomenon is reduced.

In the ground improvement device having the above configuration,
The auxiliary shearing member is provided so as to protrude in the radial direction of the outer rotating shaft member from an annular support member rotatably loosely fitted to the outer rotating shaft member or the inner rotating shaft member,
The auxiliary shearing member is configured to be displaceable in the axial direction by a cam mechanism with respect to the inner rotary shaft member and the outer rotary shaft member within a range that does not interfere with each of the pair of stirring members ,
The cam mechanism comprises a protrusion formed on one of an outer peripheral surface of the outer rotating shaft member or the inner rotating shaft member and an inner peripheral surface of the annular support member, and the outer rotating shaft member or the inner rotating shaft member. and a cam groove extending in a curved, arcuate or sinusoidal shape while being inclined with respect to the circumferential direction or horizontal direction formed on the other of the outer peripheral surface of the annular support member and the inner peripheral surface of the annular support member. preferably .

According to the soil improvement device having this configuration, the force received by the shearing assisting member from the soil to be improved can be changed in various ways, and the situation in which the rotation of the shearing assisting member around the axis is stagnant can be resolved. For this reason, when the auxiliary shearing member rotates around the axis, the auxiliary shearing member exerts a shearing force on the soil to be improved in the region sandwiched between the pair of agitating members, thereby increasing the fluidity of the soil to be improved. is improved, and the possibility of occurrence of the co-rotation phenomenon is reduced.

BRIEF DESCRIPTION OF THE DRAWINGS Explanatory drawing regarding the structure of the ground improvement apparatus as 1st Embodiment of this invention. FIG. 10 is an explanatory diagram of a first modified arrangement mode of the stirring member and shearing assisting member; FIG. 11 is an explanatory diagram of a second modified arrangement of the stirring member and shearing assisting member; FIG. 11 is an explanatory diagram of a third modified arrangement mode of the stirring member and the auxiliary shearing member;

(Configuration of ground improvement device)
A ground improvement apparatus as one embodiment of the present invention comprises a rotating shaft member 110, a relative stirring mechanism 120, and an excavating member 140, as shown in FIG.

The rotating shaft member 110 includes a substantially cylindrical inner rotating shaft member 112 extending in the vertical direction and a substantially cylindrical rotating shaft member 112 extending in the vertical direction so as to surround the inner rotating shaft member 112 over the entire circumference. It has a double shaft structure composed of the outer rotating shaft member 111 and the outer rotating shaft member 111 . Each of the outer rotating shaft member 111 and the inner rotating shaft member 112 is configured to rotate about the same axis in opposite directions by a driving motor via a counter-rotating gear mechanism (not shown) (Patent See Japanese Patent No. 3739620).

A substantially cylindrical conduit member extending vertically is inserted through the inside of the inner rotating shaft member 112 . A substantially cylindrical space surrounded by the inner peripheral surface of the conduit member constitutes a first solidifying material supply passage.

An excavating member 140 is fixed to the lower end of the inner rotating shaft member 112 . A first solidifying material discharge part is provided at the center of the excavating member 140 . The first solidifying material discharge part communicates with the first solidifying material supply path. The first solidifying material discharge part is configured to downwardly discharge the solidifying material supplied through the first solidifying material supply passage.

The relative stirring mechanism 120 includes a first stirring member 121 and a second stirring member 122 that rotate in directions opposite to each other. The first stirring member 121 is fixed to the outer rotating shaft member 111 constituting the rotating shaft member 110, and the second stirring member 122 is fixed to the inner rotating shaft member 112 constituting the rotating shaft member 110. there is Each of the first stirring member 121 and the second stirring member 122 protrudes substantially horizontally in a plurality of orientations from each of the locations spaced apart in the axial direction of the rotating shaft member 110 . The first stirring member 121 and/or the second stirring member 122 may extend obliquely upward or obliquely downward from the rotating shaft member 110 .

For example, N _i (i=1, 2 (N _i is an integer equal to or greater than 2 (eg, N _i =2))) i-th stirring members 12i are rotated N _i times with respect to the central axis of the rotating shaft member 110. The layout, shape and size of the i-th stirring member 12i are designed so as to have rotational symmetry. The arrangement and shape of the i-th stirring member 12 i less than N _i (for example, a single) i-th stirring member 12 i have N _i -fold rotational symmetry with respect to the central axis of the rotating shaft member 110 . and size may be designed. The arrangement mode, shape and/or size of the i-th stirring member 12i may be designed so that the i-th stirring member 12i of N _i or less than N _i does not have rotational symmetry.

The first stirring member 121 and/or the second stirring member 122 are provided with a second solidifying material discharging portion. The second solidifying material discharge part communicates with the second solidifying material supply path through the solidifying material introduction path formed in the first stirring member 121 and/or the second stirring member 122 . The first solidifying material supply path and the second solidifying material supply path may be composed of two independent solidifying material supply paths, or may be partly composed of a common solidifying material supply path. The second solidifying material supply path and the second solidifying material discharge part may be omitted.

The soil improvement device as one embodiment of the present invention further comprises a shear assisting member 220 as shown in FIG.

The auxiliary shearing member 220 has a substantially annular shape and is rotatably loosely fitted on the outer peripheral surface of the outer rotating shaft member 111 (or the inner rotating shaft member 112) in the intermediate region between the first stirring member 121 and the second stirring member 122. It extends substantially horizontally in a plurality of orientations from the annular support member. The shear assisting member 220 may extend obliquely upward or obliquely downward from the rotating shaft member 110 . A plurality of sets or groups of shearing assisting members 220 may be provided so as to protrude in the radial direction of the rotating shaft member 110 from each of a plurality of different locations in the axial direction of the rotating shaft member 110 .

For example, M pieces (M is an integer of 2 or more (for example, M=3)) of the auxiliary shearing members 220 have M-fold rotational symmetry with respect to the central axis of the rotating shaft member 110. 220 configurations, shapes and sizes are designed. The layout, shape, and size of the auxiliary shearing members 220 are designed so that less than M (for example, a single) auxiliary shearing member 220 has M-fold rotational symmetry with respect to the central axis of the rotating shaft member 110. may have been The arrangement, shape and/or size of the auxiliary shearing members 220 are designed so that the M or less than M shearing auxiliary members 220 do not have rotational symmetry with respect to the central axis of the rotating shaft member 110. may be

As shown in FIG. 1, the radial extension amount r0 of the shearing assisting member 220 (the farthest reaching distance from the axis when it is rotationally driven around the axis) It is smaller than the radial projection amount R1 and the radial projection amount R2 of the second stirring member 122, respectively. This is because the diameter or maximum diameter of the circular trajectory drawn by the distal portion of the one or more shearing assisting members 220 when rotated about the central axis of the rotating shaft member 110 rotates about the central axis of the rotating shaft member 110. is smaller than the diameter or the maximum diameter of the circular orbit drawn by the distal portion of each of the one or more first stirring members 121 when turned, and one or more when rotated around the central axis of the rotating shaft member 110 It means smaller than the diameter or the maximum diameter of the circular orbit drawn by the distal portions of the plurality of second stirring members 122 .

The auxiliary shearing members 220 are arranged so that the distance between the auxiliary shearing member 220 and the first stirring member 121 and the distance between the auxiliary shearing member 220 and the second stirring member 122 are substantially equal in the axial direction of the rotating shaft member 110. Alternatively, the shear assisting member 220 may be arranged such that at least two of the intervals are different. For example, the distance between the auxiliary shearing member 220 and the first stirring member 121 may be greater or smaller than the distance between the auxiliary shearing member 220 and the second stirring member 122 .

(Function of ground improvement device)
The soil to be improved is excavated by rotating the excavating member 140 integrally with the inner rotating shaft member 112 . In addition, the solidifying material is discharged to the soil to be improved from each of the first solidifying material discharging part and the second solidifying material discharging part. By rotating the first stirring member 121 and the second stirring member 122 together with the outer rotating shaft member 111 and the inner rotating shaft member 112, respectively, the soil to be improved and the solidification material are stirred and mixed.

(Effect)
According to the soil improvement device having this configuration, as the fluidity of the soil to be improved in the intermediate region sandwiched between the pair of stirring members 121 and 122 decreases, the soil is dragged by the pair of stirring members 121 and 122, respectively. As a result, the amount of soil to be improved that is flowing or moving increases. For this reason, the assisting shearing member 220 is moved along the axis of the rotating shaft member 110 in the direction in which it is dragged relatively strongly so as to be caught in the soil to be improved that is flowing or moving so as to be dragged by the pair of stirring members 121 and 122 respectively. rotate around. As a result, the auxiliary shearing member 220 applies a shearing force to the soil to be improved in the intermediate region sandwiched between the pair of stirring members 121 and 122 to improve the fluidity of the soil to be improved and eventually prevent the co-rotation phenomenon. The possibility of occurrence is reduced.

(Another embodiment of the present invention)
The radial protrusion amount r0 of the shear assisting member 220 may be smaller than at least one of the radial protrusion amount R1 of the first stirring member 121 and the radial protrusion amount R2 of the second stirring member 122. .

For example, as shown in FIG. 2, the radial extension amount r0 of the shear assisting member 220 is smaller than the radial extension amount R1 of the first stirring member 121, while the diameter of the second stirring member 122 is less than R1. The ground improvement device may be configured so as to be larger than the overhang amount R2 in the direction. This is because the diameter or maximum diameter of the circular trajectory drawn by the distal portion of the one or more shearing assisting members 220 when rotated about the central axis of the rotating shaft member 110 rotates about the central axis of the rotating shaft member 110. is smaller than the diameter or the maximum diameter of the circular orbit drawn by the distal portion of each of the one or more first stirring members 121 when turned, and one or more when rotated around the central axis of the rotating shaft member 110 It means that the distal portion of the plurality of second stirring members 122 is larger than the diameter or the maximum diameter of the circular orbit drawn.

In the shear assisting member 220, the anchoring soil pressure from the soil to be improved existing around the second stirring member 122 against the distal portion that protrudes in the radial direction compared to the second stirring member 122. can act. As a result, when the auxiliary shearing member 220 rotates about the axis so as to be caught in the soil to be improved that is flowing or moving so as to be dragged by the second stirring member 122, the soil to be improved in the upper region of the second stirring member 122 is removed. A shearing force is applied to the soil from the auxiliary shearing member 220 including the distal portion, thereby improving the fluidity of the soil to be improved and, in turn, reducing the possibility of occurrence of the co-rotation phenomenon.

As shown in FIG. 3, the radial protrusion amount r0 of the shearing assisting member 220 is equal to the radial protrusion amount R1 of the first stirring member 121 and the radial protrusion amount of the second stirring member 122. The soil improvement device may be configured to be larger than each of R2. This is because the diameter or maximum diameter of the circular trajectory drawn by the distal portion of the one or more shearing assisting members 220 when rotated about the central axis of the rotating shaft member 110 rotates about the central axis of the rotating shaft member 110. is greater than the diameter or maximum diameter of the circular orbit drawn by the distal portion of each of the one or more first stirring members 121 when it is rotated, and one or more when it is rotated around the central axis of the rotating shaft member 110 It means that the distal portion of the plurality of second stirring members 122 is larger than the diameter or the maximum diameter of the circular orbit drawn. In FIG. 3, the radial protrusion amount R1 of the first stirring member 121 is smaller than the radial protrusion amount R2 of the second stirring member 122, but the radial protrusion amount R1 of the first stirring member 121 may be greater than the amount of protrusion R2 of the second stirring member 122 in the radial direction.

In the shear assist member 220, the first and second stirring members 121 and 122, respectively, relative to the radially flared distal portion relative to the first and second stirring members 121 and 122, respectively. It is possible to apply the retaining soil pressure from the soil to be improved existing in the surrounding area. As a result, when the auxiliary shearing member 220 rotates around the axis so as to be caught in the soil to be improved that is flowing or moving so as to be dragged by the first stirring member 121 and the second stirring member 122, the first stirring member 121 and the second stirring member 122 rotate. A shearing force is applied to the soil to be improved in the intermediate region between the member 121 and the second stirring member 122 from the shearing auxiliary member 220 including the distal portion to improve the fluidity of the soil to be improved, and eventually the co-rotation phenomenon. reduction of the possibility of occurrence of

As schematically shown in FIG. 4, the shear assisting member 220 is configured such that the extending manner in the direction parallel to the axis is different for each of at least two azimuths with respect to the axis. If so, the forces acting on the shear assisting member 220 from the soil to be improved that is flowing or moving so as to be dragged by the pair of stirring members 121 and 122 are differentiated in the at least two orientations (or orientation ranges). be able to. As a result, the force that the auxiliary shearing member 220 receives from the soil to be improved can be changed in various ways, and the situation in which the rotation of the auxiliary shearing member 220 about the axis is stagnant can be resolved. Therefore, when the auxiliary shearing member 220 rotates around the axis, the shearing force is applied from the auxiliary shearing member 220 to the soil to be improved in the region sandwiched between the pair of stirring members 121 and 122, and the improvement is performed. The fluidity of the target soil is improved, and the possibility of occurrence of the co-rotation phenomenon is reduced.

In the soil improvement device, the stirring mechanism may be configured by three or more stirring members rotationally driven in different modes while avoiding interference.

In the above embodiment, the first stirring member 121 and the second stirring member 122 are rotationally driven about the same axis in opposite directions. They may be rotationally driven at different rotational speeds in the same direction around the same axis. The stirring mechanism may be composed of two or more stirring members rotationally driven around respective axes of rotating shaft members spaced apart from each other.

The shear assisting member 220 may be configured to be displaceable in the axial direction within a range that does not interfere with the pair of stirring members 121 and 122 .

The displacement is realized by, for example, a cam mechanism. The cam mechanism has a substantially cylindrical protrusion (or recess) formed on one of the inner peripheral surface of the annular support member and the outer peripheral surface of the outer rotary shaft member 111 and a circumferential or horizontal cam mechanism formed on the other. and a cam groove (or cam track) extending in a curved, arcuate or sinusoidal shape while being inclined with respect to the cam. When a force that rotates the annular support member relative to the outer rotary shaft member 111 acts on the shear assist member 220, the annular support member is guided by the cam mechanism to rotate the outer rotary shaft member 111. It can be displaced in the direction of the axis while rotating relative to.

According to the soil improvement device having this configuration, the force received by the shearing assisting member 220 from the soil to be improved can be changed in various ways, and the situation in which the rotation of the shearing assisting member 220 around the axis is stagnant can be resolved. Therefore, when the auxiliary shearing member 220 rotates around the axis, the auxiliary shearing member 220 exerts a shearing force on the soil to be improved in the region sandwiched between the pair of agitating members 121 and 122, thereby causing the improvement. The fluidity of the target soil is improved, and the possibility of occurrence of the co-rotation phenomenon is reduced.

110... rotary shaft member 111... first rotary shaft member 112... second rotary shaft member 121... first stirring member 122... second stirring member 140... excavating member 220... shearing auxiliary member.

Claims (6)

A cylindrical inner rotating shaft member and a cylindrical outer rotating shaft member surrounding the inner rotating shaft member over the entire circumference with the inner rotating shaft member partially protruding downward are rotated around their respective axes. by rotating them in mutually opposite directions, the portion of the inner rotating shaft member protruding from the outer rotating shaft member and the outer rotating shaft member are fixed so as to protrude in the radial direction thereof. A soil improvement device configured to mix and agitate soil to be improved and a solidification material by a pair of agitating members,
radially extending from the inner rotating shaft member and the outer rotating shaft member so as to be interposed between the pair of stirring members, and rotating around the axis with respect to each of the inner rotating shaft member and the outer rotating shaft member; A shearing assisting member rotatably provided in the
At least one stirring member of the pair of stirring members extends from at least one of the portion of the inner rotating shaft member protruding from the outer rotating shaft member and the outer rotating shaft member in the radial direction thereof. A ground improvement device that slopes and extends obliquely upwards or obliquely downwards . In the ground improvement device according to claim 1,
The auxiliary shearing member protrudes in the radial direction of the inner rotary shaft member and the outer rotary shaft member and extends obliquely upward or downward with respect to the radial direction.
Soil improvement device. In the ground improvement device according to claim 2,
Each of the pair of stirring members extends obliquely downward with respect to the radial direction from each of the portion of the inner rotating shaft member protruding from the outer rotating shaft member and the outer rotating shaft member. extend,
The auxiliary shearing member protrudes in the radial direction of the inner rotary shaft member and the outer rotary shaft member and extends obliquely downward with respect to the radial direction.
Soil improvement device. In the ground improvement device according to any one of claims 1 to 3 ,
The soil improvement device, wherein the auxiliary shearing member protrudes in the radial direction of the inner rotating shaft member and the outer rotating shaft member by an amount of protrusion larger than that of at least one stirring member of the pair of stirring members. In the ground improvement device according to any one of claims 1 to 4 ,
As the auxiliary shearing member, a plurality of auxiliary shearing members projecting in the radial direction of the inner rotating shaft member and the outer rotating shaft member are provided, and the plurality of auxiliary shearing members have rotational symmetry about the axis. Soil improvement equipment that is arranged not to . In the ground improvement device according to any one of claims 1 to 5 ,
The auxiliary shearing member is provided so as to protrude in the radial direction of the outer rotating shaft member from an annular support member rotatably loosely fitted to the outer rotating shaft member or the inner rotating shaft member,
The auxiliary shearing member is configured to be displaceable in the axial direction by a cam mechanism with respect to the inner rotary shaft member and the outer rotary shaft member within a range that does not interfere with each of the pair of stirring members ,
The cam mechanism comprises a protrusion formed on one of an outer peripheral surface of the outer rotating shaft member or the inner rotating shaft member and an inner peripheral surface of the annular support member, and the outer rotating shaft member or the inner rotating shaft member. and a cam groove extending in a curved, arcuate or sinusoidal shape while being inclined with respect to the circumferential direction or horizontal direction formed on the other of the outer peripheral surface of the annular support member and the inner peripheral surface of the annular support member. ing
Soil improvement device.

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