Site improvement equipment

Abstract

To provide a ground improvement device that can suppress ground rotation in various soil types. [Solution] A ground improvement device comprising an excavation blade, a stirring blade, and a co-rotation prevention blade, wherein the co-rotation prevention blade comprises a prevention blade body portion arranged from the inner diameter to the outer diameter, and a blade modification portion arranged at the outer diameter tip of the prevention blade body portion, and capable of changing the amount of outward protrusion from the tip of the prevention blade body portion, wherein the blade modification portion can be switched between a first mounting position in which it can be attached to the prevention blade body portion at a small protrusion position in which the amount of outward protrusion from the tip is small, and at a large protrusion position in which the amount of outward protrusion is greater than that of the small protrusion position, and a second mounting position which is a different position from the first mounting position, and a second mounting position in which it can be attached to the prevention blade body portion at a medium protrusion position in which the amount of outward protrusion is greater than that of the small protrusion position and less than that of the large protrusion position.

Description

Technical Field

[0001] The present invention relates to a ground improvement device provided with an anti-rotation wing.

Background Art

[0002] Patent Document 1 discloses a stirring and mixing attachment. The stirring and mixing attachment of Patent Document 1 includes a stirring wing that rotates together with a rotating rod to stir and mix excavated soil and a solidifying material, an anti-rotation wing that remains stationary to prevent the excavated soil from rotating together, and a count sensor that detects the relative rotational speed of the anti-rotation wing with respect to the rotational speed of the rotating rod.

[0003] In Patent Document 1, the relative rotational speed of the anti-rotation wing with respect to the rotational speed of the rotating rod inserted into the excavated soil is detected by the count sensor. That is, in Patent Document 1, based on the relative rotational speed, it is grasped whether the anti-rotation wing rotates together with the rotating rod and a phenomenon of the soil rotating together occurs.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, when the co-rotation phenomenon is confirmed by the count sensor, the rotating rod is pulled out from the excavated soil and re-construction is carried out. Therefore, Patent Document 1 is not a technology for fundamentally controlling the co-rotation phenomenon.

[0006] In addition, the ground to be constructed has various properties such as clayey and sandy, and there is also a situation that the likelihood of the co-rotation phenomenon occurring differs depending on the soil properties with different properties.

[0007] Therefore, the present invention aims to provide a ground improvement device that can suppress the co-rotation of the ground even in ground with various soil types. [Means for solving the problem]

[0008] The ground improvement device of the present invention comprises: an excavation blade disposed on the tip side of a rotating rod and rotating in conjunction with the rotation of the rotating rod; a stirring blade disposed in the middle of the axial direction of the rotating rod and rotating in conjunction with the rotation of the rotating rod; and a co-rotation prevention blade disposed in the middle of the axial direction of the rotating rod and rotating relative to the rotation of the rotating rod. The co-rotation prevention blade comprises a prevention blade body disposed from the inner diameter to the outer diameter, and a blade modification part disposed at the outer diameter tip of the prevention blade body, which can change the amount of protrusion outward from the tip of the prevention blade body. The blade modification part is configured to be switchable between a first mounting position in which it can be attached to the prevention blade body at a small protrusion position in which the amount of protrusion outward from the tip is small, and at a large protrusion position in which the amount of protrusion outward from the tip is larger than that of the small protrusion position, and a second mounting position which is a different position from the first mounting position, in which it can be attached to the prevention blade body at a medium protrusion position in which the amount of protrusion outward from the small protrusion position is larger than that of the large protrusion position.

[0009] According to the configuration of the ground improvement device described above, the wing modification section can be attached to the anti-rotation wing body in a first mounting position and a second mounting position. By using the first and second mounting positions interchangeably, it is possible to select large protrusion, medium protrusion, and small protrusion positions, which have different amounts of outward protrusion from the tip of the anti-rotation wing body. Therefore, the amount of penetration into the ground at the tip of the anti-rotation wing formed by the wing modification section can be selected as the amount of protrusion at the large protrusion, medium protrusion, and small protrusion positions. In this way, by selecting the amount of penetration according to the soil type of the ground, the rotational resistance of the anti-rotation wing can be adjusted, and the co-rotation of the ground can be suppressed.

[0010] In the ground improvement device of the present invention, the wing modification section is configured to be attached to the prevention wing body via a mounting member, and when it is attached in the small protruding position in the first mounting position, a small protruding hole through which the mounting member is inserted is provided, and when it is attached in the large protruding position in the first mounting position, a large protruding hole through which the mounting member is inserted is provided, both arranged radially side by side, and when it is attached in the medium protruding position in the second mounting position, a medium protruding hole through which the mounting member is inserted is provided, and this medium protruding hole is arranged opposite to the large protruding hole and the small protruding hole in a direction perpendicular to the radial direction, and may also be arranged approximately midway between the large protruding hole and the small protruding hole in the radial direction.

[0011] According to the configuration of the ground improvement device described above, the blade modification section bites into the ground and receives significant resistance in order to stop the rotation of the anti-rotation blade. However, the central protruding hole is positioned opposite the large protruding hole and the small protruding hole in a direction perpendicular to the radial direction, and is positioned approximately midway between the large protruding hole and the small protruding hole in the radial direction. Therefore, the position can be changed to the large protruding position, the central protruding position, and the small protruding position while maintaining the strength between the large protruding hole and the small protruding hole.

[0012] In the ground improvement device of the present invention, the blade modification section is formed in a plate shape having a surface, a back surface, one radial end, and the other radial end. In the first mounting position, the surface of the blade modification section faces the leading side in the rotation direction of the rotating rod, with one radial end facing radially outward and the other radial end facing radially inward when attached to the prevention wing body. In the second mounting position, the back surface of the blade modification section faces the leading side in the rotation direction of the rotating rod, with one radial end facing radially outward and the other radial end facing radially inward when attached to the prevention wing body.

[0013] According to the configuration of the ground improvement device described above, when changing the orientation of the wing modification section between the first mounting position and the second mounting position, the orientation can be easily switched by changing the orientation of the front and back of the wing modification section and attaching it to the main body of the prevention wing.

[0014] In the ground improvement device of the present invention, the blade modification section is formed in a plate shape having a surface, a back surface, one radial end, and the other radial end. In the first mounting position, the surface of the blade modification section faces the leading side in the rotation direction of the rotating rod, with the one radial end facing radially outward and the other radial end facing radially inward when attached to the prevention wing body. In the second mounting position, the surface of the blade modification section faces the leading side in the rotation direction of the rotating rod, with the other radial end facing radially outward and the one radial end facing radially inward when attached to the prevention wing body.

[0015] According to the configuration of the ground improvement device described above, when changing the wing modification section between the first and second mounting positions, the first and second mounting positions can be easily switched by changing the inner and outer diameters of the wing modification section. [Effects of the Invention]

[0016] According to the ground improvement device of the present invention, the amount of penetration of the tip of the anti-rotation wing into the ground can be adjusted, so that rotation can be suppressed even in ground with various soil types. [Brief explanation of the drawing]

[0017] [Figure 1] This is a partially fractured cross-sectional view showing the usage state of a ground improvement device according to one embodiment of the present invention. [Figure 2] A partially fractured plan view of the ground improvement device, with the stirring blades omitted. [Figure 3] This is a front view of the modified wing section. [Figure 4] This is a front view of the main body of the anti-damping wing. [Figure 5] This is a plan view of the anti-rotation wing. [Figure 6] A partial fractured plan view of the anti-rotation wing. [Figure 7] This is a front view showing the small protrusion position in the first mounting position of the modified wing section. [Figure 8] This is a front view showing the large protruding position in the first mounting position of the modified wing section. [Figure 9]It is a front view showing the middle protruding position of the second mounting posture of the same-wing change part.

Embodiments for Carrying out the Invention

[0018] Hereinafter, referring to FIGS. 1 and 9, the ground improvement device 1 according to an embodiment of the present invention will be described. As shown in FIG. 1, the ground improvement device 1 mainly includes a base machine (not shown), a leader mast erected substantially vertically from the base machine, and an agitation and mixing unit 2 installed so as to be able to move up and down with respect to the leader mast.

[0019] The agitation and mixing unit 2 includes a rotating rod (also referred to as an "auger rod") 3, an excavation head 4 provided with excavation blades 5 disposed closer to the tip (lower end) side of the rotating rod 3, and an earth auger driving device (not shown) for rotating the rotating rod 3 around its axis. The agitation and mixing unit 2 further includes an anti-rotation wing 6 and an agitation wing 7.

[0020] The rotating rod 3 is formed in a long cylindrical shape and has a passage (not shown) for passing a solidifying material (for example, a slurry-like solidifying material such as a cement-based material) inside. The passage is formed from the upper end to the lower end of the rotating rod 3. The tip of the passage is the discharge port of the solidifying material. For example, the discharge port is formed near the lower end of the rotating rod 3.

[0021] The excavation blades 5 are formed in a plate shape and are provided at 180° intervals around a rotating shaft 3A attached to the tip of the rotating rod 3. A plurality of bits 8 are detachably attached along the leading edge of the tip side of these excavation blades 5. The excavation blades 5 are disposed on the tip side of the rotating rod 3 and are configured to rotate as the rotating rod 3 rotates. The bits 8 are attached so as to be inclined in a direction parallel to the inclined surface of the excavation blade 5, that is, in a direction inclined with respect to the rotation direction of the excavation blade 5.

[0022] The anti-rotation blade 6 is positioned midway along the axial direction of the rotating rod 3 and is positioned above the drilling blade 5 at a predetermined distance. The anti-rotation blade 6 is attached to the rotating rod 3 coaxially via a boss portion 9 and is configured to rotate freely (relatively) with respect to the rotation of the rotating rod 3. As shown in Figures 5 and 6, the boss portion 9 is split in two at its radial center, and a connecting member 9A is provided on its outer circumference, extending radially outward from the boss portion 9 to connect the two split boss portions 9, with the connecting members 9A being connected to each other.

[0023] In this embodiment, as shown in Figure 2, three anti-rotation blades 6 are provided at equal intervals in the circumferential direction of the boss portion 9. However, as an alternative example, two anti-rotation blades 6 may be provided at equal intervals (180°) in the circumferential direction. In this embodiment, since three anti-rotation blades 6 are provided, one configuration of the anti-rotation blade 6 will be used to substitute for the other two configurations, and the anti-rotation blade 6 will be described in more detail.

[0024] The anti-rotation wing 6 comprises an anti-rotation wing body 10 as shown in Figure 4 and a wing modification section 11 as shown in Figure 3.

[0025] [Preventive wing body 10] The main body portion 10 of the anti-damping wing comprises a main surface portion 10a, a main back portion 10b, a main upper surface portion 10c, a main lower surface portion 10d, and a main outer end portion 10e, and is formed in a plate shape extending from the inner diameter to the outer diameter. The main surface portion 10a, the main back portion 10b, the main upper surface portion 10c, the main lower surface portion 10d, and the main outer end portion 10e are all flat.

[0026] The prevention wing body 10 extends radially outward from the boss portion 9. As shown in Figure 4, the end of the prevention wing body 10 on the boss portion 9 side is designated as the radially inward end 6B, and the extended end of the prevention wing body 10 is designated as the radially outward end 6A. This prevention wing body 10 has the same length as the drilling blade 5, centered on the rotating rod 3. In other words, the radially outward end 6A of the prevention wing body 10 has the same length as the radially outward end 5A of the drilling blade 5.

[0027] A guide projection 12 for attaching the wing modification section 11, which will be described later, is formed on the plate surface of the main body surface 10a of the prevention wing body 10. In this embodiment, the guide projection 12 has a rectangular cross-section, is positioned at the vertical center of the main body surface 10a, and extends from the radially inner end 6B to a length that does not reach the radially outer end 6A of the main body surface 10a.

[0028] The guide projection 12 has a guide upper surface portion 12a, a guide lower surface portion 12b facing the guide upper surface portion 12a, a guide front surface portion 12c that is continuous in the vertical direction between the guide upper surface portion 12a and the guide lower surface portion 12b, and a guide outer end portion 12d formed at the outer end. These guide upper surface portion 12a, guide lower surface portion 12b, guide front surface portion 12c, and guide outer end portion 12d are all flat.

[0029] At the radial outer end 6A of the main surface portion 10a of the protective wing body portion 10, an upper mounting hole 13 and a lower mounting hole 14 are formed via a guide projection 12 in the vertical center of the protective wing body portion 10. The upper mounting hole 13 is located above the upper guide surface portion 12a of the guide projection 12, near the outer guide end portion 12d. The other mounting hole 14 is located below the lower guide surface portion 12b of the guide projection 12, on the side of the outer guide end portion 12d. These upper mounting holes 13 and 14 are holes that penetrate the plate surface of the protective wing body portion 10. In this embodiment, the upper mounting hole 13 and the other mounting hole 14 of the protective wing body portion 10 have the same diameter, and as shown in Figure 4, the radial spacing width (reference distance) L3 between the upper mounting hole 13 and the other mounting hole 14 is 25 mm.

[0030] [Wing modification section 11] As shown in Figure 3, the wing modification section 11 is detachably provided so as to overlap the radial outer end 6A of the prevention wing body 10, and is configured to change the amount of radial outward protrusion from the radial outer end 6A of the prevention wing body 10. In this embodiment, the wing modification section 11 comprises a wing surface portion 11a, a wing back surface portion 11b facing the wing surface portion 11a, a radial end portion 11c that is continuous with the wing surface portion 11a and the wing back surface portion 11b at one end (outer end side), and a radial end portion 11d that is continuous with the wing surface portion 11a and the wing back surface portion 11b at the other end (inner end side), and is formed to follow the prevention wing body 10.

[0031] The wing modification section 11 is formed in a roughly oval plate shape when viewed from the wing surface 11a, with one end 11c in the wing radial direction curved outward and the other end 11d in the wing radial direction curved inward.

[0032] The wing modification section 11 has a notch 15 that is guided (fitted) to the outer end 12d side of the guide projection 12. In this embodiment, the notch 15 is formed to penetrate the plate surface of the wing modification section 11, extends from the center of the other end 11d in the wing radial direction to the one end 11c in the wing radial direction, and is formed to a length that does not reach the one end 11c in the wing radial direction.

[0033] The notch 15 has an upper notch surface 15a located above, a lower notch surface 15b facing the upper notch surface 15a below, and an outer notch end 15c that is continuous with the upper notch surface 15a and the lower notch surface 15b on the outside. Since the notch 15 is guided by the outer guide end 12d side of the guide projection 12, it is shaped to follow the guide projection 12, and the upper notch surface 15a, the lower notch surface 15b, and the outer notch end 15c are all flat.

[0034] In this embodiment, the prevention wing body 10 and the wing modification section 11 are attached by guiding the notch 15 to the outer guide end 12d side of the guide projection 12 so that they overlap. At this time, as shown in Figures 5 and 6, the height of the guide projection 12 from the main surface 10a of the prevention wing body 10 is formed to be higher than the height of the wing modification section 11 from the main surface 10a of the prevention wing body 10. Therefore, when the notch 15 is guided to the outer guide end 12d side of the guide projection 12, the guide front portion 12c of the guide projection 12 is higher than the wing surface 11a (or wing underside portion 11b) of the wing modification section 11, using the main surface 10a of the prevention wing body 10 as a reference.

[0035] When the wing modification section 11 is attached to the main body of the protective wing 10 so as to overlap it, the wing modification section 11 is configured to be able to move radially within a predetermined range relative to the main body of the protective wing 10. In other words, in this embodiment, the wing modification section 11 can be switched between a first mounting position Y1 and a second mounting position Y2.

[0036] The first mounting position Y1 is a small protrusion position δ1 in which the amount of radial outward protrusion from the radial outer end 6A of the prevention wing body 10 is small, and a large protrusion position δ2 in which the amount of protrusion from the radial outer end 6A is greater than that of the small protrusion position δ1. The first mounting position Y1 shown in Figure 7 is the position in which the amount of radial outward protrusion from the radial outer end 6A of the prevention wing body 10 is small, which is the small protrusion position δ1. Specifically, Figure 7 shows a state in which the notch 15 of the wing modification part 11 is guided by the guide projection 12 of the prevention wing body 10, so that the guide outer end 12d of the guide projection 12 and the notch outer end 15c of the notch 15 come into contact.

[0037] The first mounting position Y1 shown in Figure 8 is a position where the amount of protrusion from the radial outer end 6A of the prevention wing body 10 is greater than that of the small protrusion position δ1, resulting in a large protrusion position δ2. Specifically, Figure 8 shows a state where the notch 15 of the wing modification section 11 is guided by the guide projection 12 of the prevention wing body 10, and the outer guide end 12d of the guide projection 12 and the outer notch end 15c of the notch 15 are far apart.

[0038] The second mounting position Y2 is a different position from the first mounting position Y1. That is, the second mounting position Y2 is a medium-protrusion position δ3 in which the amount of outward protrusion is greater than that of the small protrusion position δ1 and smaller than that of the large protrusion position δ2.

[0039] To accommodate the first mounting position Y1 and the second mounting position Y2, the wing modification section 11 has one overlapping hole 16 and the other overlapping hole 17 which communicate with one mounting hole 13 and the other mounting hole 14.

[0040] As shown in Figure 3, the overlapping holes 16 and 17 are formed on one side (upper side) and the other side (lower side) of the wing modification section 11, via the notch 15 in this embodiment, in the central part of the wing modification section 11 in the vertical direction. Four overlapping holes 16 are arranged radially. Three overlapping holes 17 are arranged radially. These overlapping holes 16 and 17 are positioned to align with the mounting holes 13 and 14, respectively, when the wing modification section 11 is slid radially across the prevention wing body section 10 by guiding the notch 15 to the guide projection 12.

[0041] In this embodiment, as shown in Figure 3, the radial distance L1 between two overlapping holes 16 is 50 mm. Similarly, the radial distance L2 between two overlapping holes 17 is 50 mm. However, since the other overlapping holes 17 are positioned approximately midway between the overlapping holes 16 in a direction perpendicular to the radial direction (vertical direction), the radial distance L4 between adjacent overlapping holes 16 and one overlapping hole 17 between them is 25 mm. These overlapping holes 16 and 17 are formed to penetrate the wing modification section 11.

[0042] One mounting hole 13 and the other mounting hole 14 are located on the upper and lower sides of the prevention wing body 10, and are offset radially by a reference distance L3. Similarly, one overlapping hole 16 and the other overlapping hole 17 are located on the upper and lower sides of the wing modification section 11, and are offset radially by the same distance L4 as the reference distance L3. Furthermore, multiple pairs of one overlapping hole 16 and the other overlapping hole 17 are arranged side-by-side at a distance of twice the reference distance L3 in the radial direction; in this embodiment, three such pairs are arranged in a row. Note that the one mounting hole 13 and the other mounting hole 14 of the prevention wing body 10, and the one overlapping hole 16 and the other overlapping hole 17 of the wing modification section 11 have the same diameter.

[0043] Incidentally, bolts 18 (bolt and nut mechanism) are used as mounting members (connecting members) for attaching one mounting hole 13 and the other mounting hole 14, and one overlapping hole 16 and the other overlapping hole 17. Thus, the wing modification section 11 is attached to the anti-wing body section 10 via bolts 18.

[0044] Furthermore, since one mounting hole 13 and one mounting hole 14 are formed on one side and one on the other side of the prevention wing body 10, even if four overlapping holes 16 and three overlapping holes 17 are formed on the wing modification section 11, only one overlapping hole 16 is superimposed on the one mounting hole 13, and only one overlapping hole 17 is superimposed on the other mounting hole 14.

[0045] The stirring blades 7 are positioned midway along the axial direction of the rotating rod 3 and are positioned above the anti-rotation blades 6 at a predetermined distance. The stirring blades 7 are arranged in two stages, upper and lower, and are configured to rotate coaxially with the rotating shaft 3A and in conjunction with the rotation of the rotating rod 3. In this embodiment, two stirring blades 7 are provided, one above the other, spaced 180° apart in the circumferential direction. Each stirring blade 7 is formed to the same length as the drilling blade 5. In other words, the stirring blades 7, the anti-rotation blade body 10, and the drilling blade 5 are formed to be of the same length.

[0046] The ground improvement method using the above-described ground improvement device 1 is generally as follows: The rotating rod 3 is lowered into the ground G, and as the rotating rod 3 rotates due to the drive of the earth auger drive device, the excavation blades 5 and mixing blades 7 rotate. In addition, the excavation blades 5 are subjected to a weight (the weight of the earth auger drive device, not shown) and the weight of the rotating rod 3, and are pushed into the ground G by a belt drive using a metal chain and a rack mechanism, excavating the ground G while rotating. During excavation, the rotation of the excavation blades 5 is not stopped, and the mixing blades 7 rotate together with the excavation blades 5, and the excavated soil and the unsolidified solidifying agent slurry (a mixture of water and solidifying agent) are mixed by the mixing blades 7 to create an improved body C in the ground G. This constructs a cylindrical improved body C that will serve as the foundation for the structure.

[0047] Incidentally, in the ground improvement device 1, even when the excavation blades 5 and mixing blades 7 rotate, the anti-rotation blades 6 bite into the ground G radially outward from above relative to the excavated soil excavated by the excavation blades 5, so the excavated soil does not rotate (move in the direction of rotation). In other words, the anti-rotation blades 6 can prevent the excavated soil excavated by the rotation of the excavation blades 5 from rotating together with the excavated soil mixed by the mixing blades 7 above the anti-rotation blades 6.

[0048] However, the ground to be constructed has various properties, such as clayey and sandy soil, and the likelihood of the co-rotation phenomenon occurring differs depending on the soil type. For this reason, it is necessary to adjust the length of the co-rotation prevention wing 6.

[0049] In light of these circumstances, in this embodiment, the anti-rotation wing 6 is configured to be switched between a first mounting position Y1 and a second mounting position Y2 to change the length of the anti-rotation wing 6.

[0050] Here, we consider the case where it becomes necessary to attach the wing modification section 11 at the above-mentioned small protruding position δ1 as the first mounting position Y1.

[0051] When mounted in the small protrusion position δ1 in the first mounting position Y1, as shown in Figure 7, the one overlapping hole 16 and the other overlapping hole 17 on the radially outward side of the wing modification section 11 are overlapped with the one mounting hole 13 and the other mounting hole 14 on the prevention wing body section 10, and mounted with bolts 18. When mounted in the small protrusion position δ1, the outer guide end 12d of the guide projection 12 and the outer notch end 15c of the notch 15 are in contact. In other words, the one overlapping hole 16 and the other overlapping hole 17 on the radially outward side are the small protrusion holes that result in the small protrusion position δ1, which is the minimum amount of protrusion. In the small protrusion position δ1, the wing surface portion 11a of the wing modification section 11 faces the leading side in the rotational direction of the rotating rod 3, with one end 11c in the wing radial direction facing radially outward and the other end 11d in the wing radial direction facing radially inward, and it is mounted to the prevention wing body section 10.

[0052] At the small protruding position δ1, if the anti-rotation wing 6 bites into the ground G from above, it performs its function as an anti-rotation wing in the ground improvement method using the ground improvement device 1. Furthermore, the wing modification section 11 is formed in a substantially elliptical plate shape when viewed from the wing surface 11a, and one end 11c in the radial direction of the wing is curved outward, thereby reducing resistance with the ground G and making it easier to bite into it.

[0053] However, if the amount by which the anti-rotation wing 6 bites into the ground G from above is insufficient when the wing modification section 11 is attached at the small protrusion position δ1, it may be attached at the large protrusion position δ2, as shown in Figure 8. In this case, the one overlapping hole 16 and the other overlapping hole 17 adjacent to each other in the radially outward direction are overlapped with the one mounting hole 13 and the other mounting hole 14, respectively, and attached with bolts 18. When attached at the large protrusion position δ2, the outer guide end 12d of the guide projection 12 and the outer notch end 15c of the notch 15 are far apart. In other words, the one overlapping hole 16 and the other overlapping hole 17 adjacent to each other in the radially outward direction are large protrusion holes that result in a large protrusion position δ2, which has a greater protrusion amount than the small protrusion position δ1, which is the minimum protrusion amount. At the large protrusion position δ2, the wing surface portion 11a of the wing modification portion 11 faces the leading side in the rotational direction of the rotating rod 3, and one end 11c in the radial direction of the wing is attached to the prevention wing body portion 10 with the other end 11d in the radial direction facing outward.

[0054] Incidentally, the radial spacing between the overlapping holes 16 is 50 mm, and the radial spacing between the overlapping holes 17 is 50 mm. Therefore, at the large protrusion position δ2, the wing modification section 11 protrudes radially outward from the anti-rotation wing body 10 by 50 mm compared to the small protrusion position δ1. At the large protrusion position δ2 shown in Figure 8, if the anti-rotation wing 6 bites into the ground G from above, it will perform its function as an anti-rotation wing in the ground improvement method using the ground improvement device 1.

[0055] By the way, even when the wing modification section 11 is attached to the prevention wing body section 10 at the large protrusion position δ2 shown in Figure 8, if the amount of penetration into the ground G is insufficient, the radially adjacent overlapping holes 16 and 17 are further overlapped with the mounting hole 13 and 14, respectively, and attached with bolts 18. In this case as well, the radially adjacent overlapping holes 16 and 17 are designated as large protrusion holes. The radial spacing between the overlapping holes 16 is 50 mm, and the radial spacing between the overlapping holes 17 is 50 mm, resulting in a protrusion amount 50 mm larger than that in Figure 8.

[0056] In this case, even in the first mounting position Y1, the wing surface portion 11a of the wing modification portion 11 faces the leading side in the rotational direction of the rotating rod 3, and one end 11c in the wing radial direction is attached to the prevention wing body portion 10 with the other end 11d in the wing radial direction facing outward.

[0057] By the way, when moving from the small protrusion position δ1 to the large protrusion position δ2 of the wing modification section 11, it is possible that the wing modification section 11 may protrude too much. In this case, the wing modification section 11 is set to the second mounting position Y2. That is, the radial spacing between one mounting hole 13 and the other mounting hole 14 is set to 25 mm, and the radial spacing between adjacent overlapping holes 16 and one overlapping hole 17 is also set to 25 mm, which is used to change the amount of protrusion of the wing modification section 11.

[0058] In other words, the wing modification section 11, which was initially in the mounting position Y1, is inverted. As a result, as shown in Figure 9, one mounting hole 13 and the other overlapping hole 17 on the outer side overlap, and the other mounting hole 14 and the adjacent one overlapping hole 16 on the outer side overlap. Then, the one mounting hole 13 and the other overlapping hole 17 on the outer side are attached with bolts 18, and the other mounting hole 14 and the adjacent one overlapping hole 16 on the outer side are attached with bolts 18. In this case, the other overlapping hole 17 on the outer side and the adjacent one overlapping hole 16 on the outer side become protruding holes.

[0059] If we consider that the radial spacing between one mounting hole 13 and the other mounting hole 14 is 25 mm, and that the radial spacing between adjacent overlapping holes 16 and one overlapping hole 17 is also 25 mm, then the intermediate protrusion position δ3 when the wing modification section 11 is in the second mounting position Y2 is the amount of protrusion between the small protrusion position δ1 in the first mounting position Y1 and the large protrusion position δ2 in the first mounting position Y1. Specifically, the intermediate protrusion position δ3 is a protrusion of 25 mm from the small protrusion position δ1 and a retraction of 25 mm from the large protrusion position δ2. In other words, the intermediate protrusion position δ3 is a different amount of protrusion from the small protrusion position δ1 and the large protrusion position δ2.

[0060] In the central protruding position δ3, the wing modification section 11 is reversed compared to the first mounting position Y1, so the underside surface 11b of the wing modification section 11 faces the leading side in the rotational direction of the rotating rod 3, and one end 11c in the radial direction of the wing is attached to the main body of the anti-wing wing 10 facing radially outward, and the other end 11d in the radial direction of the wing is attached radially inward.

[0061] Furthermore, when the other overlapping hole 17 and the one overlapping hole 16, which are aligned radially inward, and the one mounting hole 13 and the other mounting hole 14 are attached with bolts 18 in the wing modification section 11, the resulting central protrusion position δ3 has a larger protrusion amount than the aforementioned central protrusion position δ3. In this case, since the one overlapping hole 16 and the other overlapping hole 17, which are aligned radially, are spaced 50 mm apart, the central protrusion position δ3 will have a protrusion amount of 50 mm at each interval.

[0062] According to the configuration of the ground improvement device 1, when changing the wing modification section 11 from the first mounting position Y1 to the second mounting position Y2, the underside portion 11b of the wing modification section 11 is attached to the prevention wing body portion 10, thereby easily switching from the first mounting position Y1 to the second mounting position Y2.

[0063] At the central protruding position δ3, if the anti-rotation wing 6 bites into the ground G from above, it fulfills its function as an anti-rotation wing in the ground improvement method using the ground improvement device 1. Furthermore, since the other end 11d in the radial direction of the wing is curved inward, it reduces resistance with the ground G and makes it easier to bite into it.

[0064] Thus, in this embodiment, the wing modification section 11 can be attached to the anti-rotation wing body section 10 in a first mounting position Y1 and a second mounting position Y2. Therefore, by using the first mounting position Y1 and the second mounting position Y2, it is possible to select a large protrusion position δ2, a medium protrusion position δ3, and a small protrusion position δ1, which have different amounts of radial outward protrusion from the tip of the anti-rotation wing body section 10. Thus, in the anti-rotation wing 6 formed by the wing modification section 11, the amount of penetration of the tip of the anti-rotation wing 6 into the ground G can be selected as the amount of protrusion at the large protrusion position δ2, the medium protrusion position δ3, and the small protrusion position δ1. By selecting the amount of penetration according to the soil type of the ground G, the rotational resistance of the anti-rotation wing 6 can be adjusted, and the co-rotation of the ground G can be suppressed.

[0065] Furthermore, according to the configuration of the ground improvement device 1, the blade modification section 11 bites into the ground G to stop the rotation of the anti-rotation blade 6 and receives significant resistance. However, since the central protruding hole is positioned approximately midway between the large protruding hole and the small protruding hole in a direction perpendicular to the radial direction, it can be repositioned to the large protruding position δ2, the central protruding position δ3, and the small protruding position δ1 while maintaining the strength between the large and small protruding holes.

[0066] The present invention can be modified in various ways without departing from its spirit. Furthermore, the specific configuration of each part is not limited to the embodiments described above.

[0067] In the above embodiment, the notch 15 of the wing modification section 11 was formed to penetrate the plate surface of the wing modification section 11, extending from the center of the other end 11d in the radial direction to the one end 11c in the radial direction, but not reaching the one end 11c in the radial direction. However, the notch 15 can also be formed to extend from the center of the other end 11d in the radial direction to the one end 11c in the radial direction, and reach the one end 11c in the radial direction. In this case, the wing modification section 11 can guide the notch 15 to the guide projection 12, and can also be configured to reverse the left and right sides of the wing modification section 11, that is, to reverse the one end 11c in the radial direction and the other end 11d in the radial direction.

[0068] In this embodiment, in the first mounting position Y1, the front wing surface portion 11a of the wing modification portion 11 can be attached to the main body of the anti-blade wing 10 with the leading side in the rotation direction of the rotating rod 3, one end 11c in the wing radial direction facing outward, and the other end 11d in the wing radial direction facing inward. In the second mounting position Y2, the front wing surface portion 11a of the wing modification portion 11 can be attached to the main body of the anti-blade wing 10 with the leading side in the rotation direction of the rotating rod 3, the other end 11d in the wing radial direction facing outward, and one end 11c in the wing radial direction facing inward.

[0069] According to the configuration of this ground improvement device 1, when changing the wing modification section 11 between the first mounting position Y1 and the second mounting position Y2, the first mounting position Y1 and the second mounting position Y2 can be easily switched by changing the inner and outer diameters of the wing modification section 11. In the above embodiment of the ground improvement device 1, there was a notch 15 and a guide projection 12, but the notch 15 and the guide projection 12 can be omitted.

[0070] In the above embodiment, the wing modification portion 11 is formed in a substantially oval plate shape when viewed from the wing surface portion 11a, with one end 11c in the wing radial direction curved outward and the other end 11d in the wing radial direction curved inward. However, the curved portion may also have a chamfered edge. Even if the curved portion has a chamfered edge, it reduces resistance with the ground G and makes it easier to penetrate.

[0071] In the above embodiment, four overlapping holes 16 are provided via notches 15, and three overlapping holes 17 are provided via notches 15. However, five or more overlapping holes 16 can be provided while maintaining the spacing between adjacent overlapping holes 16, and four or more overlapping holes 17 can be provided while maintaining the spacing between adjacent overlapping holes 17. With this configuration, it is possible to further increase the amount of protrusion from the first mounting position Y1 of the small protrusion position δ1 to the first mounting position Y1 of the large protrusion position δ2. In addition, it is possible to set the second mounting position Y2 of the medium protrusion position δ3 more times from the small protrusion position δ1 to the large protrusion position δ2.

[0072] In the above embodiment, the main body of the protective wing 10 is provided with one mounting hole 13 and the other mounting hole 14 as holes. However, the one mounting hole 13 and the other mounting hole 14 can also be configured as protrusions that fit into the one overlapping hole 16 or the other overlapping hole 17.

[0073] In the above embodiment, a bolt 18 (bolt-nut mechanism) was used as the mounting member. However, a pin that fits into the hole may also be used.

[0074] In the above embodiment, the prevention wing body 10 was described as having the same length as the drilling blade 5 with respect to the rotating rod 3. However, even if the prevention wing body 10 is shorter than the drilling blade 5 when comparing the length of the prevention wing body 10 and the drilling blade 5, it is still possible to attach the blade modification section 11 to the prevention wing body 10. [Explanation of Symbols]

[0075] 1: Ground improvement device, 2: Mixing and stirring section, 3: Rotating rod, 3A: Rotating shaft, 4: Drilling head, 5: Drilling blade, 5A: Radial outer end, 6: Co-rotation prevention blade, 6A: Radial outer end, 6B: Radial inner end, 7: Mixing blade, 8: Bit, 9: Boss section, 9A: Joining member, 10: Prevention blade body section, 10a: Body surface section, 10b: Body underside section, 10c: Body top surface section, 10d: Body bottom surface section, 10e: Body outer end, 11: Blade modification section, 11a: Blade surface section, 11b: Blade underside section, 11c: Blade radial direction One end, 11d: radial end of wing, 12: guide protrusion, 12a: upper surface of guide, 12b: lower surface of guide, 12c: front surface of guide, 12d: outer end of guide, 13: one mounting hole, 14: other mounting hole, 15: notch, 15a: upper surface of notch, 15b: lower surface of notch, 15c: outer end of notch, 16: one overlapping hole, 17: other overlapping hole, 18: bolt, C: improved body, G: ground, Y1: first mounting position, Y2: second mounting position, δ1: small protrusion position, δ2: large protrusion position, δ3: medium protrusion position

Claims

1. A drilling blade positioned at the tip of the rotating rod and rotating in conjunction with the rotation of the rotating rod, A stirring blade is positioned midway along the axial direction of the rotating rod and rotates in conjunction with the rotation of the rotating rod, The rotating rod is positioned midway along its axial direction and includes an anti-rotation vane that rotates relative to the rotation of the rotating rod, The anti-rotation wing comprises an anti-rotation wing body portion arranged from the inner diameter to the outer diameter, and a wing modification portion arranged at the outer tip of the anti-rotation wing body portion, which can change the amount of outward protrusion from the tip of the anti-rotation wing body portion. The wing modification section is, A first mounting position in which the anti-wing body can be attached is such that the amount of protrusion outward from the tip is small, and the amount of protrusion outward from the tip is larger than that of the small protrusion position, A second mounting position, which is different from the first mounting position, is a medium-protrusion position in which the amount of protrusion is greater than the small protrusion position and smaller than the large protrusion position, and the second mounting position is such that the wing can be attached to the main body of the prevention wing. A ground improvement device configured to allow switching between modes.

2. The wing modification section is configured to be attached to the main body of the prevention wing via a mounting member. When mounted in the small protruding position in the first mounting position, a small protruding hole through which the mounting member is inserted, and when mounted in the large protruding position in the first mounting position, a large protruding hole through which the mounting member is inserted, are arranged radially side by side. When mounting in the centrally protruding position in the second mounting posture, a centrally protruding hole is formed through which the mounting member is inserted. The ground improvement device according to claim 1, wherein the central protruding hole is arranged opposite to the large protruding hole and the small protruding hole in a direction perpendicular to the radial direction, and is positioned approximately midway between the large protruding hole and the small protruding hole in the radial direction.

3. The wing modification section is formed in a plate shape having a surface, a back surface, one radial end, and the other radial end. In the first mounting position, the surface of the wing modification portion faces the leading side in the rotational direction of the rotating rod, and the wing is attached to the main body of the prevention wing with one radial end facing radially outward and the other radial end facing radially inward. The ground improvement device according to claim 1 or claim 2, wherein in the second mounting position, the back surface of the wing modification portion faces the leading side in the rotational direction of the rotating rod, and is attached to the prevention wing body with one radial end facing radially outward and the other radial end facing radially inward.

4. The wing modification section is formed in a plate shape having a surface, a back surface, one radial end, and the other radial end. In the first mounting position, the surface of the wing modification portion faces the leading side in the rotational direction of the rotating rod, and the wing is attached to the main body of the prevention wing with one radial end facing radially outward and the other radial end facing radially inward. The ground improvement device according to claim 1 or claim 2, wherein in the second mounting position, the surface of the wing modification portion faces the leading side in the rotational direction of the rotating rod, and the other radial end is attached to the prevention wing body with the radial end facing radially outward and the radial end facing radially inward.

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