JP4890622B2 - Ground improvement mixing and stirring device, and ground improvement mixing and stirring method - Google Patents

Description

  The present invention relates to a mixing and stirring device for ground improvement of soft ground in civil engineering and construction foundation work, and a mixing and stirring method for ground improvement. Specifically, a mixing / stirring device for ground improvement provided with a stirring blade that rotates and rotates together with a rotating rod to mix and stir the excavated soil and solidified material, and a co-rotation preventing blade that stops stationary and prevents the excavated soil from rotating together. With such an apparatus, the rotating rod penetrates into the ground from the ground surface (ground), the excavating blade provided at the tip of the rotating rod or a portion near the tip, and the stirring blade provided behind the rotating blade ( Simply mix and agitate the excavated earth and sand in the ground with a mixing stirrer blade) and discharge a slurry-like solidification material (consolidation material) such as lime or cement. The present invention relates to a ground improvement mixing and stirring method for improving the ground by mixing and stirring the earth and sand and the solidified material, and then solidifying them.

  Conventionally, this kind of ground improvement mixing / stirring device includes a drilling blade provided at or near the tip of a rotating rod (a drilling shaft rotated by a rotation driving means), and a stirring blade provided behind it. In addition, a co-rotation prevention wing having a larger diameter (projection length in the lateral direction from the rotating rod) than the outer diameter (excavation rotating diameter) of this excavating blade is rotatably mounted on the rotating rod via a boss. In addition, there is known one that prevents co-rotation of excavated earth and sand (a lump) (Patent Document 1). Further, the co-rotation preventing blade is a horizontal shaft body, and the horizontal shaft body is provided with a cylindrical body that is rotatable about the axis of the horizontal shaft body inside the outer diameter (excavation rotation diameter) of the drilling blade. Further, the cylindrical body has at least three projecting pieces extending outward from the cylindrical body at substantially equal angular intervals when viewed from the axial direction of the cylindrical body as mixing and stirring means for excavated soil. On the other hand, when the rotating rod is rotated when the horizontal shaft is not rotating around the axis of the rotating rod, the rotating rod contacts the protruding piece and the protruding piece together with the cylindrical body. There is one provided with at least one rotation drive unit that rotates the shaft around the axis of the horizontal shaft body (Patent Document 2).

  In the prior art of Patent Document 1 described above, when the ground (soil) is dug by the rotation of the excavating blade, the ground is excavated into a cylindrical shape having the same diameter as the outer diameter of the excavating blade, and is simultaneously stirred by the stirring blade. The At this time, since the co-rotation prevention blade has a longer protrusion length than the excavation blade, the end of the common rotation prevention blade is outside the excavation site (unexcavated soil) by the difference in length (biting length). It is pushed into the ground in such a way that it is pushed into the part) and becomes constrained. For this reason, the co-rotation preventing wing does not rotate around the axis of the rotating rod or the rotation is restricted. As a result, during this excavation process, together with the excavating blade and the stirring blade, a so-called coagulant phenomenon (sediment) that tries to rotate around the rotating rod together with the dumping blade becomes a co-rotation preventing blade. Therefore, the excavation soil co-rotation is stopped. And, in this mixing and stirring state of the excavated soil, while discharging the slurry (liquid) solidified material from the tip of the rotating rod, mixing and stirring this and the excavated soil, after lifting the rotating rod, By solidifying it, it is possible to obtain a high-quality improved body that is not heterogeneous, such as a large soil mass remaining in the improved body or a solidified material that is unevenly distributed and solidified. Further, the technique described in Patent Document 2 applies the rotation drive unit to the projecting piece, and rotates the projecting piece around the axis of the horizontal shaft body together with the cylindrical body, as described above. In addition to preventing the excavated soil from co-rotating, it is mixed and stirred three-dimensionally.

  By the way, in order to more reliably stop or restrict the rotation of the co-rotation preventing wing with the above-described conventional technology, the protrusion length of the co-rotation preventing wing is lengthened, and the erosion soil is eaten into the unexcavated soil at the outer end. You just need to increase the length. However, the greater the length, the greater the resistance to bite into unexcavated soil. In addition, there is a problem that it is easy to collide with a large stone or rubble, and it is easy to be forced to stop construction. For this reason, conventionally, the biting length of the tip portion of the co-rotation preventing wing is set as small as possible to facilitate construction and improve efficiency.

  On the other hand, the above-mentioned co-rotation preventing wing is rotatably attached to the rotating rod, and in the excavation process, it is only in plan view and stopped by the resistance force at the tip that has digged into the ground outside the excavation range. is there. For this reason, when the sticking force of stone, debris, and excavated soil is large, the force that the excavated soil adheres to the agitating blade in a dumping shape and rotates the anti-rotating blade in the same manner as the rotating rod prevents co-rotation. It may exceed the resistance of the ground that holds the wings against rotation. In such a case, the co-rotation preventing wing rotates and causes co-rotation of the excavated soil. In addition, the same thing occurs when a foreign object such as a stone is caught between the co-rotation prevention blade and the excavation blade or between the co-rotation prevention blade and the stirring blade. On the other hand, the occurrence of the co-rotation phenomenon cannot be visually recognized from the outside, and as a result, the quality of the improved body is deteriorated. The same applies to the technique described in Patent Document 2. That is, in the technique described in Patent Document 2, if the horizontal shaft body forming the co-rotation preventing wing rotates in the same manner around the axis of the rotating rod, it cannot only prevent co-rotation of the excavated soil around the rotating rod. In addition, co-rotation may be promoted, and three-dimensional mixed stirring cannot be obtained.

  Under such circumstances, there has been proposed a mixing and stirring device for ground improvement provided with a monitoring device for monitoring the co-rotation of excavated soil during construction (Patent Documents 3 and 4). In this stirring and mixing device, as a non-contact type count sensor, the magnet is fixed in the recess provided on the co-rotation prevention wing side, while the rotary rod is provided with a recess provided at a position facing the magnet. A magnetic proximity switch is housed, and when the magnet approaches a certain range, this is detected, and the number of times (relative rotational speed) is counted to stop or rotate the co-rotation prevention blade. It is configured to check and monitor the status. That is, with this count sensor, the relative rotation speed of the co-rotation preventing blade with respect to the rotating rod is detected, and if the relative rotation speed is substantially the same as the rotation speed of the rotating rod, the co-rotation preventing blade is stopped. On the other hand, it seems that no co-rotation of the excavated soil occurs. On the other hand, if the relative rotational speed is significantly lower than the rotational speed of the rotating rod, the co-rotation preventing wing rotates, and the co-rotation of the excavated soil occurs. It will be. Thus, the monitoring is performed.

  In the mixing and stirring device for ground improvement provided with the monitoring device, a transmission cable for outputting an electrical signal for detecting the relative rotational speed is supplied from a magnetic proximity switch provided in the thick section of the rotating rod. It passes through the hole penetrating to the upper end of the rotating rod, is pulled out to the outside through a slip ring (swivel joint) provided at the upper end, and is connected to a counter device installed on the ground. That is, a signal indicating the relative rotational speed is transmitted through the transmission cable and received by the counter device.

Japanese Patent Publication No.58-29374 JP-A-8-120665 JP 2000-144703 A JP 2001-323454 A

  However, the detection method using the magnetic switch having the above configuration has the following problems to be solved. This is because the excavation head of the mixing and stirring device for ground improvement excavates the ground, and mixes and stirs the excavated earth and sand (aqueous slurry) in the ground. Therefore, the count sensor as described above is placed under severe conditions in the ground close to liquefaction, that is, earth and sand. Therefore, it has a serious problem that it is basically fragile. Further, the rotating rod is usually made of iron (magnetic material) and is easily affected by iron sand contained in the earth and sand. Therefore, there is a problem that reliability in detection is low.

  In addition, the rotating rod and the co-rotation preventing wing cannot be employed in a precise or complicated structure in consideration of the use conditions, and therefore, usually, the rotating rod and the co-rotation preventing wing are only mounted in a rotatable paired relationship. . Accordingly, there is a gap between the pair and the occurrence of wear on the surface of the pair is large. For this reason, earth and sand, iron sand, etc. can easily enter the gap, and in this sense, there is a problem that the count reliability is applied.

  Furthermore, when a transmission cable is provided along the rotating rod, not only is the cable required, but there is a high risk of short-circuiting based on the usage conditions. In some cases, cable connection means are usually required. On the other hand, when an electric signal is transmitted by a wireless transmission means without using such a transmission cable, there is a problem that a high cost is incurred. In Patent Document 3, it is said that a contact-type sensor equipped with a limit switch or the like may be used as a count sensor. However, such a process is a mixed state process close to liquefaction of earth and sand and slurry. When it is used in the above, its reliability is very low, and there is a problem that it cannot withstand practical use or its durability is extremely low. In any case, in the prior art described in Patent Documents 3 and 4, since the count sensor is attached to a site in the ground, there is a problem in durability and reliability.

  An object of the present invention is to provide a technique that solves the problems of the monitoring technique of the rotation state of the co-rotation preventing blade in the above-described prior art.

According to the first aspect of the present invention, there is provided a rotary rod having a drilling blade at a tip or a portion near the tip, a stirring blade provided on the rotary rod above the drilling blade, and the rotary rod rotating about its axis. In the mixing and stirring device for ground improvement, comprising a co-rotation preventing blade that is freely attached and has a protruding length that has a projecting length larger than the drilling rotation diameter by the excavating blade,
A vibration generator that generates vibration by colliding with the co-rotation preventing blade whose rotation is restricted during excavation process by rotation of the rotating rod is provided directly or indirectly on the rotating rod. To do.
According to a second aspect of the present invention, there is provided a rotating rod provided with a drilling blade at a tip or a portion near the tip, a stirring blade provided on the rotating rod above the drilling blade, and the rotating rod rotating about its axis. In the mixing and stirring device for ground improvement, comprising a co-rotation preventing blade that is freely attached and has a protruding length that has a projecting length larger than the drilling rotation diameter by the excavating blade,
A vibration generator that generates vibrations by colliding with an excavation blade, a stirring blade, or a collided portion provided in the rotation rod that rotates in the excavation process by the rotation of the rotating rod is directly or indirectly to the co-rotation preventing blade. It is characterized by being provided.

The invention according to claim 3 is characterized in that the vibration generating body is provided via a spring body, and the mixing and stirring device for ground improvement according to any one of claims 1 and 2 It is.
In the invention according to claim 4, the vibration generated when the excavated excavated soil and the solidified material are mixed and agitated is detected by a sensor, and from the detection data, The ground improvement mixing / stirring method using a stirring device according to any one of claims 1 to 3, comprising a method for detecting a rotation state.

According to a fifth aspect of the present invention, there is provided a rotating rod having a drilling blade at a tip or a portion near the tip, a stirring blade provided on the rotating rod above the drilling blade, and the rotating rod rotating about its axis. A grounding improvement mixing / stirring device, comprising a co-rotation prevention blade that is freely attached and has a protrusion length that is larger than a rotation diameter of excavation by the excavation blade,
The stirring blade extends laterally from the rotating rod, has a horizontal shaft body having a protruding length smaller than the excavation rotation diameter of the excavating blade, and is fitted on the horizontal shaft body so as to be rotatable about the horizontal axis. A rotating body, and at least three projecting pieces extending outwardly of the rotating body at substantially equal angular intervals when viewed from the axial direction of the rotating body on the outer peripheral surface of the rotating body,
The projecting piece collides with the co-rotation preventing blade whose rotation is restricted during the excavation process by the rotation of the rotating rod, so that the rotating body rotates intermittently around the horizontal axis of the horizontal shaft body. Mixing for ground improvement, mixing for ground improvement using a stirring device, stirring method,
When mixing and stirring the excavated excavated soil and the solidified material, vibration generated when the protruding piece collides with the co-rotating blade is detected by a sensor, and the rotation of the co-rotating blade is detected from the detected data. It includes a method for detecting a stop state or a rotation state.

According to a sixth aspect of the present invention, there is provided a rotary rod having a drilling blade at a tip or a portion near the tip, a stirring blade provided on the rotary rod above the drilling blade, and the rotary rod rotating about its axis. A grounding improvement mixing / stirring device, comprising a co-rotation prevention blade that is freely attached and has a protrusion length that is larger than a rotation diameter of excavation by the excavation blade,
The co-rotation preventing wing extends laterally from the rotating rod and has a horizontal shaft body having a projecting length larger than the excavation rotation diameter of the excavation blade, and the horizontal shaft body on the inner side of the excavation rotation diameter of the horizontal shaft body. A rotating body that is externally fitted and arranged to be rotatable around the horizontal axis, and a mixing and stirring means for excavating soil on the outer peripheral surface of the rotating body at substantially equal angular intervals when viewed from the axial direction of the rotating body. And at least three protruding pieces extending outward of the rotating body,
When the horizontal rod does not rotate around the axis of the rotary rod, the rotary rod collides with the projecting piece when the rotary rod rotates, and the projecting piece together with the rotary body is placed on the rotary shaft. In the ground improvement mixing, which is provided with at least one rotation drive unit that rotates intermittently around the axis, the ground improvement mixing using the stirring device, the stirring method,
When mixing and agitating the excavated excavated soil and the solidified material, vibration generated when the rotation drive unit collides with the protruding piece is detected by a sensor, and the rotation of the co-rotation prevention blade is detected from the detected data. It includes a method for detecting a stop state or a rotation state.

  The invention according to claim 7 is the mixing and stirring method for ground improvement according to claim 6, wherein the rotation drive unit is the stirring blade or the excavation blade.

  According to the mixing / stirring device for ground improvement of the present invention, when excavating the ground by rotating the rotating rod at a predetermined number of revolutions per unit time, when the co-rotation preventing wing is in plan view and stopped, The generation state of the vibration, that is, the period of the peak of the vibration wave is basically a predetermined one. Therefore, when mixing and stirring the excavated soil and the solidified material using such a mixing and stirring device, vibration generated when the vibration generator collides with the co-rotation preventing blade is detected by a sensor. It is possible to detect and detect the rotation stop state or the rotation state of the co-rotation prevention wing from the detection data. Thereby, the co-rotation of excavated soil can be monitored. That is, if the number of occurrences of vibration wave peaks per time is a predetermined value or close to it, it is recognized that the co-rotation preventing blade is stopped or substantially stopped, and mixing and stirring is preferable. It can be confirmed that it is done. Therefore, in this case, the construction may be continued as it is. On the other hand, when the number of occurrences of vibration wave peaks per hour is significantly smaller than the predetermined one, the co-rotation preventing blade is rotating and mixing excavation of excavated soil is not preferable. I understand that. Therefore, in such a case, it is possible to take measures such as excavation again by pulling out the rotating rod from the ground.

  What should be noted in the present invention is that a rotation stop state or a rotation state around the rotating rod of the co-rotation preventing wing is detected by detecting the vibration with a sensor. That is, the vibration propagates as it is not only from the position where the vibration occurs, but also to a portion connected to the rotating rod, not only the metallic rotating rod itself (usually a steel pipe). Therefore, a sensor for detecting vibration (an acceleration sensor or a vibration sensor for detecting vibration) can be attached to an upper end portion of the rotating rod located on the ground via a swivel fitting or the like. . That is, including the cable that transmits the detected signal to the control device, the sensor is placed on the ground surface, not under the harsh conditions and environment in the ground close to liquefaction, so to speak of earth and sand as in the prior art. Since it can be installed, the above-mentioned problems in the prior art can be solved at once, and the reliability and durability can be remarkably enhanced, and the construction cost can be reduced. In the present invention, the “spring body” is exemplified by a leaf spring or a coil spring, but may be any other flexible structure.

  In addition, although Claim 6 and 7 are the cases where what is called a three-dimensional stirring apparatus is used, the vibration which generate | occur | produces when the said drive part for rotation as a vibration generation body collides with a protrusion piece is detected in this case. By doing so, the same effect as described above can be obtained.

The front view of an example of embodiment of the mixing and stirring apparatus for ground improvement which materialized this invention. The figure seen from arrow A1 of FIG. BB sectional drawing of FIG. The front view of the modification of FIG. The front view of the modification of FIG. The front view of the other example of embodiment of the mixing and stirring apparatus for ground improvement which actualized this invention. The partial view seen from arrow A2 of FIG. The front view of the other example of embodiment of the mixing and stirring apparatus for ground improvement which actualized this invention.

  Embodiments of the present invention will be described with reference to FIGS. In the figure, reference numeral 100 shows an example of a mixing / stirring device for ground improvement. A rotating rod 101 constituting the mixing / stirring device has a hollow shaft (tube) shape and constitutes a rotation driving means provided at the upper end thereof. For example, the auger motor (hereinafter referred to as a motor) 105 is configured to rotate by rotational driving. Then, from the tip (lower end of FIG. 1) side to the rotating rod 101, the excavating blade 11, the co-rotation preventing blade 21, and the stirring blade 31 are perpendicular to the rotating rod 101, respectively. It is provided in a shape protruding in the lateral direction.

  The excavation blade 11 excavates the ground 900 with a predetermined excavation rotation diameter (rotation diameter D1), and is fixed to the rotation rod 101 by welding or bolting. Further, the agitating blade 31 is a place where the excavation progresses and the agitating blade 31 itself enters the ground 900 to mix and agitate the excavated soil in the ground. It is formed from a strip-shaped iron plate having a protruding length that becomes a rotation diameter D <b> 2 smaller than that, and is fixed to the rotating rod 101. That is, the stirring blade 31 rotates together with the rotating rod 101 and mixes the solidified material (consolidated material) made of, for example, cementitious slurry and discharged from the discharge port 103 at the tip of the rotating rod 101 with the excavated soil. It is configured to stir. The solidified material is configured to be pressure-fed through a tube (not shown) passed through the rotating rod 101 from an external slurry supply means (not shown).

  On the other hand, the co-rotation prevention wing 21 is made of a strip-shaped iron plate, and is provided so as to project laterally from an annular body 23 that is externally fitted to the rotary rod 101 so as to protrude laterally. Is set to have a diameter D3 larger than the protruding length (rotating diameter D1) of the excavating blade 21. The movement of the annular body 23 is restricted by a restriction ring portion 110 provided on the rotating rod 101 so as not to move forward and backward (up and down) with respect to the rotating rod 101. Thus, after the rotating rod 101 is rotated by the motor 105 at the upper end and excavation of the ground 900 by the excavating blade 11 is started, when the excavated soil is further agitated by the agitating blade 31, Of the tip portion of 21, the portion 25 located outside the excavation diameter (excavation rotation diameter D1) by the excavation blade 11 is used as the ground 900 site (unexcavated soil portion) outside the excavation diameter (excavation rotation diameter D1). Encroach. By doing so, the co-rotation preventing wing 21 itself does not rotate with respect to the ground 900 in plan view. That is, the co-rotation prevention blade 21 that does not rotate in this way is attached to the excavation blade 11 and the stirring blade 31 in a dumping manner during the excavation and mixing process, and the rotation rod 101 is combined with the excavation blade 11 and the stirring blade 31. The excavated soil is sufficiently mixed and stirred together with the solidified material in the form of a slurry because the excavated soil is prevented from co-rotating around the excavated soil. Note that a plurality (set) of stirring blades 31 and co-rotation preventing blades 21 may be provided above and below the rotating rod 101 while maintaining a gap. However, in this example, one is provided for simplicity of explanation. It is assumed.

  Further, in this example, when the stirring blade 31 rotates together with the rotating rod 101, the vibration generator 41 provided to give an impact to the stopped co-rotation preventing blade 21 includes a spring material (for example, It is fixed to the lower edge of one blade (one side) of the stirring blade 31 via a leaf spring 43 made of spring steel or the like. That is, a vibration generator (for example, an iron rod or an iron short cylinder) 41 is fixed via a spring member 43 fixed to the stirring blade 31 in an arrangement that hangs downward, as shown in FIGS. As described above, the stirring blade 31 rotates with the rotating rod 101 so that the vibration generating body 41 collides with the co-rotation preventing blade 21 to generate vibration. After the collision, as shown in FIG. 2, the spring member 43 is elastically deformed to overcome the co-rotation preventing wing 21 and continue to rotate. In this example, the co-rotation preventing wing 21 is provided in a shape extending symmetrically with respect to the rotating rod 101 in plan view (see FIG. 1 from above). For this reason, every time the rotating rod 101 makes one rotation, the vibration generating body 41 is configured to collide with the co-rotation preventing blade 21 twice.

  In this example, as described above, the motor 105 that rotationally drives the rotating rod 101 is attached to the upper end of the rotating rod 101. A sensor (for example, an acceleration sensor) 51 that detects vibration generated when the vibration generating body 41 collides with the co-rotation preventing wing 21 is attached to the upper end portion of the casing that surrounds the motor 105.

  From the acceleration sensor 51, a transmission cable 61 for extracting and transmitting the detected vibration as an electrical signal is connected to a signal receiving control device 71 arranged outside. And it is comprised so that the state of a vibration wave may be output by output display means, such as the monitor 81 attached to this control apparatus, and it has comprised the detection apparatus.

  In the mixing / stirring device 100 for improving the ground as described above, the rotating rod 101 is set up vertically, rotated, and excavated by the excavating blade 11 at the tip thereof. The end portion 25 is encroached into the unexcavated soil outside the excavation diameter D1, the excavation proceeds, and the excavated soil is stirred by the rotating stirring blade 31. Then, the solidified material is discharged into the excavated soil while rotating the rotating rod 101 at a predetermined rotational speed (rpm), and the excavated soil is mixed with the solidified material by the excavating blade 11 and the stirring blade 31 that rotate together with the rotating rod 101. Stir. Thereafter, the rotating rod 101 is pulled out from the ground, and an improved consolidated body is obtained after solidification with a solidifying material. In this mixing and stirring process, the co-rotation preventing blade 21 has its end 25 encroached into the unexcavated soil outside the excavation rotation diameter D1, so that it rotates around the rotating rod 101. Is regulated. For this reason, the excavated soil to rotate (co-rotate) around the rotating rod 101 together with the excavating blade 11 and the stirring blade 31 is rotated (so-called co-rotating) by the co-rotation preventing blade 21 whose rotation is restricted. Be blocked.

  And in the mixing for ground improvement of the said example, the mixing by the stirring apparatus 100, and the stirring process, the vibration generating body 41 collides with the co-rotation prevention blade 21 fundamentally with a predetermined period, and this is repeated. At this time, when the co-rotation preventing wing 21 is stopped in plan view, the vibration generator 41 collides with the co-rotation preventing wing 21 twice at a predetermined cycle every time the rotating rod 101 makes one rotation. To do. The vibration corresponding to the collision is detected by the sensor 51 and displayed on the ground monitor 81 or recorded in the recording device. As a result, if the number of occurrences of vibration corresponding to the number of collisions is approximately twice the number of rotations of the rotating rod 101, the co-rotation preventing blade 21 is substantially stationary in the ground 900 and the slurry of the excavated soil is solidified. The material is mixed and stirred in a desired state. Therefore, it is determined that the improved consolidated body after consolidation is homogeneous and has high strength.

  On the other hand, when the number of vibrations is significantly less than twice the number of rotations of the rotating rod 101, the co-rotation preventing wing 21 is not in the desired stop state or close to it in the ground 900, and is considerably high. It is rotating and it can be determined that excavated soil co-rotates. Therefore, in such a case, it is possible to respond in real time by pulling up the rotating rod 101 and re-digging, or replacing the co-rotation prevention wing 21 with one having a longer protruding length and re-digging. .

  The important points are as follows. In the present invention, since the vibration as described above is detected, the sensor 51 can be installed on the ground (on the ground) 900 instead of in the ground, such as being attached to the casing of the motor 105 at the upper end of the rotating rod 101. Is a point. That is, such vibration is generated at a location where the vibration generating body 41, which is a location where the vibration is generated, collides with the metallic rotating rod 101 (usually a steel pipe), such as the upper end of the rotating rod 101, from the location where the vibration generator 41 collides. The sensor 51 (vibration sensor) for detecting vibration is attached to the casing of the motor 105 located on the ground surface or the upper end portion of the rotating rod 101 via a swivel fitting as in this example. I can leave. Thereby, the transmission cable (electric wire) 61 for transmitting the signal detected by the sensor 51 does not need to be routed in the ground 900, and can be connected to the control device 71 installed on the ground as it is. As described above, the sensor 51 can be installed on the ground 900 instead of the harsh conditions and environment in the ground 900 in which the earth and sand and the slurry-like solidified material are liquefied as in the prior art. Like the count sensor in the prior art described above, there is no damage or the like caused by being provided in the ground. Therefore, the specific effect that the reliability and durability can be remarkably enhanced is obtained.

  In the above example, it has been described that the vibration generating body 41 collides with the co-rotation preventing wing 21 twice each time the rotating rod 101 makes one rotation. However, as shown in FIG. Each time the rotating rod 101 makes one revolution, the collision convex part 27 that protrudes upward is provided on the upper edge of the rotation rod 41 so that the vibration generating body 41 collides with the collision convex part 27. The vibration generator 41 may collide with the co-rotation preventing wing 21 once. That is, if a specially shaped portion (collision convex portion 27) is provided on the co-rotation preventing wing 21 and the vibration generating body 41 collides with the special shape portion, the uneven rotation of the co-rotation preventing wing 21 can be prevented. Also effective. In the example of FIG. 4, the only difference is that the impacted convex portion 27 that protrudes upward is provided on the upper edge of one wing of the co-rotation preventing wing 21. In the following examples, only differences from the previous example will be described. In the above example, the co-rotation preventing wing is embodied in both wings, but it is obvious that this may be a single wing (a wing shape protruding only on one side). Each time the rotating rod 101 makes one rotation, the vibration generator 41 collides with the co-rotation preventing wing 21 once.

  In the above example, the case where the vibration generator 41 is provided so as to hang down on the stirring blade 31 has been described. However, as shown by a two-dot chain line in FIG. It may be provided upright via 43. Further, in each of the above examples, the case where the vibration generator 41 is indirectly provided on the rotating rod 101 by providing the vibration generator 41 on the stirring blade 31 or the excavation blade 11 has been described. As indicated by the dotted line, it may be directly attached to the rotating rod 101 via the bent spring body 43 or the like instead of the stirring blade 31 or the excavation blade 11 so as to collide with the co-rotation prevention blade.

  Further, as shown in FIG. 5, a stirring blade 31 that rotates with the rotating rod 101 is provided on the co-rotation preventing blade 21 that should stop the vibration generating body 41 via the spring body 43. When the motor rotates, it may collide with the vibration generating body 41. Similarly, as shown by a two-dot chain line in FIG. 5, the vibration generating body 41 is provided on the co-rotation preventing blade 21 so as to hang down via the spring body 43, and the vibration is generated when the excavation blade 11 rotates. You may make it collide with the generator 41. FIG. From this, it is clear that the impacted part not intended for excavation or stirring is separately fixed and formed on the rotating rod, and the vibration generator 41 provided on the co-rotation prevention blade 21 is rotated. Vibration may be generated by the collision of the colliding part rotating together with the rod 101.

  Moreover, the mixing / stirring device for ground improvement used in the present invention is not limited to the one in which the vibration generating body is attached via the spring body. FIG. 6 and FIG. 7 show an example thereof. In the mixing and stirring apparatus 200 shown in FIG. 6, the vibration generating body is configured by the stirring blade 231 as follows. That is, in each of the above examples, the case where the stirring blade 31 is embodied as a simple airfoil having a strip plate shape has been described. However, in this example, the stirring blade 231 is formed as follows, and the vibration generator is formed as follows. It is composed. In other words, in this example, the stirring blade 231 extends laterally from the rotating rod 101, and has a horizontal shaft body 251 having a projection length equal to or smaller than the excavation rotation diameter D1 of the excavation blade 11, and is fitted on the horizontal shaft body 251. And a cylindrical rotating body 261 arranged so as to be rotatable about its horizontal axis, and an outer side of the rotating body 261 on the outer peripheral surface of the rotating body 261 at substantially equal angular intervals when viewed from the axial direction of the rotating body. And four rod-like projecting pieces 241 extending in the direction. The projecting piece 241 collides with the co-rotation preventing wing 21 whose rotation is restricted during the excavation process by the rotation of the rotating rod 101, so that the cylindrical rotating body 261 is moved around the horizontal axis of the horizontal axis 251. It is configured to rotate intermittently. That is, by causing the projecting piece 241 to collide with the stopped co-rotation preventing wing 21 so that the pin gear meshes, the rotating body 261 rotating around the rotating rod 101 together with the projecting piece 241 is rotated around the horizontal shaft body. It is configured as follows. For this reason, the co-rotation preventing blade 21 may be a simple airfoil double airfoil having a strip shape as in the above example, but in this example, when viewed from the axial direction of the rotating rod 101, for example, the rotating rod 101 Are arranged as a + shape extending four at 90 degree intervals around the axis.

  When the ground 900 is improved in the ground improvement mixing / stirring apparatus 200, the rotation of the projecting piece 241 is controlled in the excavation process by the rotation of the rotating rod 101 based on the above configuration. The cylindrical rotating body 261 is intermittently rotated around the horizontal axis of the horizontal shaft body 251 by colliding with the gears so as to mesh with each other. For this reason, in such a mixing and stirring apparatus 200, the rotating protruding piece 241 is used as a vibration generator. That is, when the excavated excavated soil and the solidified material are mixed and agitated, the sensor 51 provided with the vibration generated when the projecting piece 241 forming the vibration generator collides with the co-rotation preventing wing 21 as in the above example. The rotation stop state or the rotation state of the co-rotation prevention blade 21 can be detected from the detection data. In this embodiment, when the co-rotation preventing wing 21 is stopped, the projecting piece 241 provided on the left and right horizontal shaft bodies 251 is rotated four times when the rotating rod 101 makes one rotation. Since there is a collision at the time of the engagement, the rotation stop state or the rotation state of the co-rotation preventing blade 21 can be determined in the same manner as in the above example based on the vibration generated in the collision. In this example, since a pair of left and right stirring blades 231 having four projecting pieces 241 are provided, the state of vibration is complicated, so that only one of them is provided to facilitate the detection. It is good to have

  In the above example, the description has been given of the case where the co-rotation preventing wing 21 is embodied as a simple airfoil having a strip shape, but the co-rotation preventing wing is not limited to such in the present invention. Even in the case of a mixing and stirring apparatus having a three-dimensional mixing and stirring action as shown in FIG.

  That is, in the mixing and stirring apparatus 300 of FIG. 8, the co-rotation preventing blade 321 extends laterally from the rotary rod 101 and has a horizontal shaft body 351 having a projecting length larger than the excavation rotation diameter D1 of the excavation blade 11, and the horizontal shaft body. 351, a rotary body 361 that is externally fitted to the horizontal shaft body 351 inside the excavation rotation diameter D1 and is rotatably arranged around the horizontal axis, and mixing of excavated soil on the outer peripheral surface of the rotary body 361 As a stirring means, four projecting pieces 341 having four rod shapes extending outward from the rotating body 361 at substantially equal angular intervals when viewed from the axial direction of the rotating body 361 are provided. The rotating rod 101 collides with the rod-shaped protruding piece 341 when the rotating rod 101 rotates when the horizontal shaft 351 does not rotate around the axis of the rotating rod 101 and the protruding piece 341 together with the rotating body 361. 4 are provided at equiangular intervals around the axis of the rotating rod 101. The rotating driving shaft 401 is rotated intermittently around the axis of the horizontal shaft 351 like a pin gear. In this example, the rotation drive shaft 401 or the projecting piece 341 forms a vibration generator.

  Therefore, when the excavated soil is excavated using the mixing and agitating apparatus 300 of FIG. 8 and mixed and agitated, the tip 25 of the horizontal shaft body 351 forming the co-rotation preventing blade 21 is cut into the unexcavated soil and stopped. In other words, when the excavated excavated soil and the solidified material are mixed and agitated, vibration generated when the rotary drive unit 401 collides with the protruding piece 341 is attached in the same manner as in the above examples. It can detect with the sensor 51, and can detect the rotation stop state or rotation state of the co-rotation prevention wing 21 in the same manner as in the previous example. Instead of providing the rotation drive unit 401 as in this example, the agitating blade 31 or the excavating blade 11 may be caused to collide with the protruding piece 341 and the vibration at the time of the collision may be detected.

  In the above description, the sensor 51 is described as being attached to the casing of the motor 105 attached to the upper end of the rotating rod 101. However, when the rotational driving of the rotating rod 101 is not performed at the upper end of the rotating rod 101, the rotating rod 101 is used. The sensor 51 can also be attached to the upper end of 101 via a swivel joint (metal fitting). The attachment position of the sensor 51 may be a position where vibration can be detected, and may be set appropriately.

  The sensor only needs to be able to detect the above-described vibration, that is, the state of occurrence of the vibration, and detect the stop state or the rotation state of the co-rotation preventing wing. Accordingly, a configuration using a metal strain gauge or a semiconductor strain gauge is used. An acceleration sensor, an impact sensor, or various types of vibration sensors can be used.

11 Excavation blades 21 and 321 Co-rotation prevention blades 31 and 231 Agitation blades 41 Vibration generator 43 Spring material 100, 200, 300 Mixing and stirring device 101 for ground improvement Rotary rods 241 and 341 Protruding pieces 251 and 351 Horizontal shaft body 261 , 361 Rotating body 401 Drive unit for rotation

Claims (7)

A rotating rod provided with a drilling blade at the tip or a portion near the tip, an agitating blade provided on the rotating rod above the drilling blade, and attached to the rotating rod so as to be rotatable about its axis. In a mixing / stirring device for ground improvement comprising a co-rotation preventing wing having a protruding length that is larger than the excavation rotation diameter,
A vibration generator that generates vibration by colliding with the co-rotation preventing blade whose rotation is restricted during excavation process by rotation of the rotating rod is provided directly or indirectly on the rotating rod. Mixing and stirring device for ground improvement. A rotating rod provided with a drilling blade at the tip or a portion near the tip, an agitating blade provided on the rotating rod above the drilling blade, and attached to the rotating rod so as to be rotatable about its axis. In a mixing / stirring device for ground improvement comprising a co-rotation preventing wing having a protruding length that is larger than the excavation rotation diameter,
A vibration generator that generates vibrations by colliding with an excavation blade, a stirring blade, or a collided portion provided in the rotation rod that rotates in the excavation process by the rotation of the rotating rod is directly or indirectly to the co-rotation preventing blade. A mixing / stirring device for ground improvement characterized by being provided.   The mixing and stirring device for ground improvement according to any one of claims 1 and 2, wherein the vibration generating body is provided via a spring body.   Including a method of detecting the vibration generated when mixing and stirring the excavated excavated soil and the solidified material with a sensor and detecting the rotation stop state or the rotation state of the co-rotation preventing blade from the detection data. The mixing for ground improvement according to any one of claims 1 to 3, and the mixing and stirring method for ground improvement using a stirring device. A rotating rod provided with a drilling blade at the tip or a portion near the tip, an agitating blade provided on the rotating rod above the drilling blade, and attached to the rotating rod so as to be rotatable about its axis. A grounding improvement mixing / stirring device comprising a co-rotation preventing wing having a projecting length larger than a drilling rotation diameter,
The stirring blade extends laterally from the rotating rod, has a horizontal shaft body having a protruding length smaller than the excavation rotation diameter of the excavating blade, and is fitted on the horizontal shaft body so as to be rotatable about the horizontal axis. A rotating body, and at least three projecting pieces extending outwardly of the rotating body at substantially equal angular intervals when viewed from the axial direction of the rotating body on the outer peripheral surface of the rotating body,
The projecting piece collides with the co-rotation preventing blade whose rotation is restricted during the excavation process by the rotation of the rotating rod, so that the rotating body rotates intermittently around the horizontal axis of the horizontal shaft body. Mixing for ground improvement, mixing for ground improvement using a stirring device, stirring method,
When mixing and stirring the excavated excavated soil and the solidified material, vibration generated when the protruding piece collides with the co-rotating blade is detected by a sensor, and the rotation of the co-rotating blade is detected from the detected data. A mixing / stirring method for ground improvement comprising a method for detecting a stopped state or a rotating state. A rotating rod provided with a drilling blade at the tip or a portion near the tip, an agitating blade provided on the rotating rod above the drilling blade, and attached to the rotating rod so as to be rotatable about its axis. A grounding improvement mixing / stirring device comprising a co-rotation preventing wing having a projecting length larger than a drilling rotation diameter,
The co-rotation preventing wing extends laterally from the rotating rod and has a horizontal shaft body having a projecting length larger than the excavation rotation diameter of the excavation blade, and the horizontal shaft body on the inner side of the excavation rotation diameter of the horizontal shaft body. A rotating body that is externally fitted and arranged to be rotatable around the horizontal axis, and a mixing and stirring means for excavating soil on the outer peripheral surface of the rotating body at substantially equal angular intervals when viewed from the axial direction of the rotating body. And at least three protruding pieces extending outward of the rotating body,
When the horizontal rod does not rotate around the axis of the rotary rod, the rotary rod collides with the projecting piece when the rotary rod rotates, and the projecting piece together with the rotary body is placed on the rotary shaft. In the ground improvement mixing, which is provided with at least one rotation drive unit that rotates intermittently around the axis, the ground improvement mixing using the stirring device, the stirring method,
When mixing and agitating the excavated excavated soil and the solidified material, vibration generated when the rotation drive unit collides with the protruding piece is detected by a sensor, and the rotation of the co-rotation prevention blade is detected from the detected data. A mixing / stirring method for ground improvement comprising a method for detecting a stopped state or a rotating state.   The mixing and stirring method for ground improvement according to claim 6, wherein the driving unit for rotation is the stirring blade or the excavation blade.

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