JP4887460B1 - Ground compaction device - Google Patents

Abstract

The object of the present invention is to push the excavated earth and sand into the outside in the radial direction without carrying it to the ground at the time of excavation, and to consolidate the hole wall and to easily supply supply materials such as sand, gravel or aggregate and solidified material. Provided is a ground compaction device that can easily construct a foundation and can simplify the structure and work.
SOLUTION: A base end portion is supported by a work machine 2 so as to be movable up and down, and an opening portion 5 for introducing a replenishing material 4 such as sand, gravel or aggregate and a solidifying material into a peripheral wall is provided in a circumferential direction and an axial direction. A plurality of cylindrical casings 3 formed at appropriate intervals, and a rotating shaft that is rotated forward or reversely by a rotation drive unit 9 that is inserted along the axis of the casing 3 and provided at the base end of the casing 3. 8 and provided at the front end of the rotary shaft 8 to excavate the ground G by forward rotation and consolidate the excavated earth and sand toward the hole wall 13b, and reversely rotate the replenishment material 4 in the casing 3 to the hole of the excavation hole. And a compacted portion 6 that press-fits to the hole bottom 13b side and forms the columnar foundation 21.
[Selection] Figure 1

Description

  The present invention relates to a ground compacting device that improves soft soil in a columnar shape, and more particularly to a ground compacting device that improves compaction performance.

  As one method for consolidating soft ground, a columnar consolidation method (also called a sand pile method) based on an excavation earth auger is known. In this method, after excavating the ground to the required depth with an earth auger, the earth and sand added to the ground soil previously dug by reverse rotation of the earth auger is sent to the bottom of the excavation hole and consolidated, A compacting foundation (columnar foundation, also called a sand pile) is created in the ground as the earth auger gradually pulls up from the excavation hole against the load applied from the work equipment side. Is.

  However, in the above construction method, earth and sand are fed along the longitudinal direction of the earth auger by reverse rotation of the earth auger, but due to the mounting angle of the spiral blade of the earth auger, the component in the vertical direction of the pressure becomes higher, Does not spread so much in the lateral direction (outwardly of the digging hole), and the sediment immediately compacts in the vertical direction to generate a consolidation reaction force. It is difficult to create.

  Further, in the above construction method, since a difference in the degree of consolidation occurs due to a load that resists the consolidation reaction force that pushes up the earth auger, it is necessary to apply a sufficient load from the work machine side. About 10 tons are necessary, and this is a limitation when trying to develop a small machine in accordance with the circumstances of a narrow residential area in an urban area.

  In order to solve such a problem, the present inventor has previously proposed a ground compaction device that can easily form a columnar base body having a sufficient strength in the lateral direction (see Patent Document 1). This ground compaction device is provided so that a base end portion can be moved up and down by a work machine, and a rotary shaft having a rotation driving unit at the base end portion and a sediment such as excavated sediment along the rotary shaft are provided. It is provided at the transport part (spiral blade) and the tip of the rotating shaft, and excavation of the ground is possible by forward rotation, and the sand and sand from the transport part is pushed outward in the radial direction of the excavation hole by reverse rotation And a compacting cam having a predetermined shape having at least two cam surfaces having an arcuate cross section.

Japanese Patent No. 3259910

  However, in the ground compaction device, while excavating the ground, the excavated soil is carried to the ground by a spiral wing and excavated to the required depth, and only pure sand (for example, mountain sand) for sand pile formation is transported to the compaction cam. When trying to create a high-strength sand pile by feeding in, not only pure sand but also soil in the hole wall will be sent by the spiral wing, and a sand pile mixed with sand and soil will be created. May not be suitable for high-strength columnar foundations. As a countermeasure, the present inventor has also proposed an invention in which a cylindrical casing is provided so as to surround the periphery of the rotating shaft, and only pure sand is fed to the compaction cam by the casing. In this case, since the outer peripheral surface of the casing is in surface contact with the hole wall, it sticks to the hole wall and the frictional resistance increases, which may be a great resistance to digging the ground.

  Moreover, when constructing a sand pile of pure sand only, it is necessary to treat excavated earth and sand carried to the ground. In addition, when sand is fed and consolidated by a compaction cam, the hole wall is not consolidated, so the sand may be pushed inwardly in the radial direction of the drilling hole and a large amount of sand may be required. It is possible that there is. Moreover, although the hopper for supplying sand is provided in the upper end part of the said casing, it is necessary to supply sand with respect to the hopper with heavy machinery, such as a bucket crane, and an operation | work is difficult.

  The present invention has been made in view of the above circumstances, and it is possible to press the digging earth and sand to the outside in the radial direction during excavation to consolidate the hole wall, and sand, gravel or aggregate and It is an object of the present invention to provide a ground compacting device that can easily supply a replenishing material such as a solidified material, easily form a columnar foundation, and can simplify the structure and work.

In order to achieve the above-described object, the present invention has a work machine in which a base end portion is supported so as to be movable up and down, and an opening for feeding a supplemental material such as sand, gravel or aggregate and a solidifying material to a peripheral wall. A plurality of cylindrical casings formed at appropriate intervals in the direction and the axial direction, and rotation that is rotated forward or reversely by a rotation drive unit that is inserted along the axial center in the casing and provided at the base end of the casing. The shaft is provided at the tip of the rotating shaft, and the ground is excavated by forward rotation, the excavated soil is consolidated to the hole wall side, and the replenishment material in the casing is pressed into the hole bottom side of the excavation hole by reverse rotation. And a compaction unit comprising a compaction part for forming a columnar foundation , wherein the opening is narrowed in the peripheral wall of the casing, and the position of the vertical rib between the openings is circumferential in the axial direction of the casing. It is formed in a honeycomb shape that changes sequentially. The on ground around the casing, characterized in that the hopper for introducing into the casing of the replenishment material from the opening is placed.

The consolidated portion has two semi-disc shaped blade members intersecting in an X shape when viewed from the side with respect to the rotation axis, and lower end edges opposite to each other as viewed from above than the casing. It consists of a screw part provided so as to protrude outward, and is arranged between one upper edge part and the other lower edge part of the two blade members and swings to the upper edge part via a hinge. It hangs down and closes when the rotary shaft is rotating forward to prevent the intake of excavated sediment into the casing, and opens when the rotary shaft rotates backward to supply supply material from the casing to the drilling hole. It is preferable that a check valve made of a plate-shaped valve body that is allowed is provided.

The hopper includes an annular or arc-shaped leg portion placed on the upper surface of the ground, an annular or planar arc-shaped rising portion that rises from the leg portion, and an annular shape that is formed with a diameter increasing upward from the rising portion. Or it is preferable to have a plane arc-shaped hopper part .

  It is preferable that a non-hole portion not having the opening in a predetermined range is formed on the outer peripheral surface on the front end side of the casing in order to prevent inflow and circulation of excavated earth and sand into the casing during excavation.

  According to the present invention, the excavated earth and sand can be pushed radially outward during excavation to consolidate the hole wall, and supply materials such as sand, gravel or aggregate and solidified material can be easily supplied. Thus, the columnar foundation can be easily created, and the structure and work can be simplified.

1 schematically shows a ground compaction apparatus according to an embodiment of the present invention. (A) is a top view of a screw part, (b) is a XX arrow side view of (a). It is a top view which shows an example of a hopper. It is a top view which shows the other example of a hopper. It is a figure explaining the operation | work by a ground compaction apparatus, (a) is a figure at the time of ground excavation work, (b) is a figure at the time of ground excavation work completion, (c) is a figure at the time of ground compaction work, (d) is a ground It is a figure at the time of completion | finish of consolidation operation | work. It is a figure which shows schematically the modification of the principal part of a ground compaction apparatus, (a) is a cross-sectional side view, (b) is the YY sectional view taken on the line of (a).

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is explained in full detail based on an accompanying drawing.

  As shown in FIG. 1, the ground compaction apparatus 1 of the present embodiment includes a cylindrical casing 3 that is long in the vertical direction and supported by a work machine 2 [see FIG. Yes. The casing 3 is made of a tubular steel pipe, for example, a cylindrical steel pipe. The length of the casing 3 is 5 to 8 m, for example, depending on the columnar base body to be created, and the diameter of the casing 3 is 300 to 500 mm. The upper end portion (base end portion) of the casing 3 is closed by detachably attaching an end plate 3a by bolting, and the lower end portion (tip end portion) of the casing 3 is an open end.

  In the peripheral wall of the casing 3, there are openings 5 in the circumferential direction and the axial direction in which the supply material 4 such as sand, gravel or aggregate and solidified material can be supplied or charged at the height position of the ground G. Are formed at appropriate intervals. As the replenishment material 4, a wide variety of materials can be used including a combination of a plurality of materials, and aggregates and various solidification materials (cement etc.) that can be flowed by the ground compaction device 1. It is possible to create a columnar foundation with the necessary strength.

  In order to ensure the strength of the casing 3, it is preferable that the adjacent openings 5 are arranged so as to be shifted in the circumferential direction so as not to be aligned in the axial direction of the casing 3. For example, the opening 5 is formed in a so-called honeycomb shape in which turtle shell-shaped ones are arranged in a staggered manner as in the illustrated example. By forming in this way, the strength of the casing 3 can be improved and the replenishment material 4 can be smoothly fed. The opening 5 may be a quadrangle as shown in FIG. 5, or may be a triangle, a circle, an ellipse, or the like.

  Further, a predetermined range, for example, W = 1 m, is provided on the outer peripheral surface of the lower end side of the casing 3 in order to prevent inflow and circulation of the excavated earth and sand from the opening portion 5 into the casing 3 during excavation by driving the screw portion 6 described later. It is preferable that a non-porous portion 7 not having the opening 5 is formed.

  A rotation shaft 8 is inserted into the casing 3 along the axial center, and a rotation capable of switching the rotation direction for rotating the rotation shaft 8 forward or backward on the end plate 3a at the upper end of the casing 3 is possible. A drive unit 9 is provided. This rotational drive part 9 consists of a hydraulic motor with a gear, for example.

  At the upper end portion of the casing 3, a locked portion 11 that is locked to a lifting / lowering hook 10 of the working machine 2 and suspends the ground compacting device 1 is provided directly or on the end plate. Is provided indirectly. As shown in FIG. 5A, the working machine 2 has a lead portion 12 that is held upright on the ground, and the lifting hook 10 is connected to the lead portion 12 via an endless chain (not shown). An elevating rotation driving unit (not shown) is provided for elevating and lowering. In addition, as the work machine 2, as long as the ground compaction apparatus 1 can be lifted and pushed downward, for example, a truck crane for burying a power pole may be used.

  The lower end portion of the rotating shaft 8 protrudes from the lower end portion of the casing 3, and the ground G can be excavated by forward rotation at the lower end portion of the rotating shaft 8, and the replenishment material in the casing 3 by reverse rotation. A screw portion 6 is provided as a consolidation portion for pushing 4 into the hole bottom 13b side of the excavation hole 13 and radially outward to perform consolidation. The screw portion 6 is composed of two semi-disc-shaped blade members 14 and 15 in this embodiment, and the two blade members 14 and 15 intersect the rotation shaft 8 in an X shape when viewed from the side. It is preferable that lower end edges 14b, 15b opposite to each other as viewed from above are provided so as to protrude outward from the casing 3 (FIGS. 1 and 2 (a)). )reference).

  In order to make it easy to carry out the replenishment material 4 from the casing 3, upper edge portions 14 a and 15 a of the blade members 14 and 15 are provided to extend into the casing 3, or It is preferable that at least one spiral blade 16 is provided in a portion corresponding to the non-hole portion 7. Further, in order to smoothly convey the replenishment material 4 put into the casing 3 from the hopper 20 through the opening 5, the rotating shaft 8 is provided with a plurality of spiral blades intermittently at predetermined intervals. Or are provided continuously. The tip of the lower end portion of the rotary shaft 8 is a sharp portion 8a protruding at an acute angle.

  The screw portion 6 has a check valve 17 that prevents the earth and sand excavated during the forward rotation from being taken into the casing 3 and allows the supply of the replenishment material 4 from the casing 3 to the excavation hole 13 during the reverse rotation. Is provided. In the illustrated example, the check valve 17 includes, as shown in FIGS. 2A and 2B, one upper edge 14a, 15a and the other lower edge 15b of the two blade members 14, 15. 14b and plate-like valve elements 19 which are swingably suspended from the upper edge portions 14a and 15a via hinges 18 and are rotated forward (arrow A). Is closed as shown by a solid line to prevent the intrusion of excavated earth and sand into the casing, and when the rotating shaft 8 rotates in the reverse direction (arrow B), the valve is opened as shown by a virtual line to send out the replenishment material. It comes to allow.

  On the ground G around the casing 3, a hopper 20 for introducing the replenishment material 4 into the casing 3 from the opening 5 is installed. As shown in FIG. 3, the hopper 20 of the present embodiment includes an annular rising portion 20 a through which the casing 3 can be inserted, and an annular leg formed on the ground G and formed below the rising portion 20 a. It integrally has a portion 20b and a hopper portion 20c having a diameter expanded in a reverse truncated cone shape upward from the rising portion 20a.

  During excavation, the replenishment material 4 can be easily charged and filled into the casing 3 under the ground G from the opening 5 by the hopper 20, and the opening 5 of the casing 3 under the ground G is closed with the replenishment material 4. In addition to preventing the excavated earth and sand from the hole wall 13a from entering the casing 3, the surface of the casing 3 is reduced in friction resistance when the surface of the casing 3 advances in close contact with the hole wall 13a. As shown in FIG. 4, the hopper may be a divided hopper 20 </ b> D that is one of a plurality of hoppers 20 in FIG. 3 divided into a plurality of, for example, four in the circumferential direction. Depending on the situation, it can be used properly so as not to interfere with the work. The split hopper 20D includes a planar arc-shaped rising portion 20a ′, a planar arc-shaped leg portion 20b ′ formed below the rising portion 20a ′ and placed on the ground G, and the rising portion 20a. It has a flat arc-shaped hopper portion 20c formed upward from '.

  Next, the operation of the ground compacting device 1 having the above configuration will be described. First, as shown in FIG. 5 (a), the ground compaction device 1 is vertically set up by the work machine 2 on the ground G to be ground compacted, and the screw portion 6 at the lower end portion of the rotary shaft 8 is properly adjusted by the rotation drive unit 9. While rotating, the ground G is excavated by applying a downward load to the ground compacting device 1 by the up-and-down rotation driving part of the lead part 12 of the work machine 2. In this excavation process, the ground G is excavated by the blade members 14 and 15 constituting the screw part 6, and the excavated earth and sand (ground soil) is put into the casing 3 by the check valve 17 as shown by a dotted arrow F in FIG. Is prevented from flowing into the tangential direction or radially outward, and the hole wall 13a of the excavation hole 13 is thereby consolidated. Note that the casing 3 does not rotate in any process including the excavation process.

  In this excavation process, by supplying the replenishment material 4 to the hopper 20, the replenishment material 4 is charged into the casing 3 under the ground G from the opening 5 on the outer periphery of the casing 3 of the ground compacting device 1, Drilling to the drilling depth of. Thus, as shown in FIG. 5 (b), when the ground G is excavated to a predetermined excavation depth, the rotation direction of the rotation drive unit 9 is switched and the rotation axis as shown in FIG. 5 (c). By reversing the rotation 8, the replenishment material 4 in the casing 3 is supplied and pushed into the hole bottom 13 b side (downward) and tangentially or radially outwardly by the blade members 14, 15 of the screw part 6 to be consolidated. The

  As a result, the columnar base body 21 is sequentially formed upward from the hole bottom 13b, and the ground compaction device 1 is raised by the reaction force as the columnar base body 21 is formed. Since the replenishment material 4 in the casing 3 also decreases with this rise, the replenishment material 4 is sequentially supplied to the hopper 20 so that the replenishment material 4 is always filled in the casing 3 below the ground G. In this way, as shown in FIG. 5 (d), the columnar basic body 21 is formed up to the hole opening, thereby completing the formation.

  In this consolidation process, since the hole wall 13a of the excavation hole 13 is preliminarily consolidated using excavation earth and sand in the excavation (drilling) process, the replenishment material 4 may be pushed outward in the radial direction more than necessary. In addition, the usage amount of the replenishment material 4 can be reduced. Moreover, since excavated earth and sand are used for consolidation of the hole wall 13a and are not carried to the ground, processing of excavated earth and sand is not required. Moreover, since the columnar foundation body 21 can be formed only with the pure supply material 4 without mixing the earth and sand of the ground with the replenishment material 4 or mixing the excavated earth and sand, the columnar foundation body 21 having high strength can be easily formed. Can be created.

  The blade members 14 and 15 of the screw portion 6 receive a consolidation reaction force from the hole bottom 13b side, but receive a greater consolidation reaction force from the hole wall 13a side (the radial direction of the drilling hole). The ground compaction device 1 is not pushed up unintentionally like the conventional construction method. For this reason, it is not necessary to apply a load against the compaction reaction force to the ground compaction device 1, and therefore the work machine 2 is not necessarily enlarged and can be miniaturized. The degree of compaction can be inferred from the torque applied to the rotary drive unit 9 and the columnar foundation body 21 can be formed by gradually pulling up the ground compaction device 1 while maintaining a desired compaction density. .

  Thus, according to the ground compaction device 1, the base end is supported by the work machine 2 so as to be movable up and down, and the opening for introducing the replenishment material 4 such as sand, gravel or aggregate and solidified material to the peripheral wall 5 is formed by a cylindrical casing 3 in which a plurality of cylinders 5 are formed at appropriate intervals in the circumferential direction and the axial direction, and a rotational drive unit 9 that is inserted along the axis of the casing 3 and provided at the base end of the casing 3. A rotating shaft 8 that is rotated or reversely rotated, and a ground G that is provided at a lower end portion of the rotating shaft 8 is excavated by the forward rotation, and the excavated earth and sand is consolidated to the hole wall 13a side, and in the casing 3 by reverse rotation. The replenishment material 4 is pushed into the hole bottom 13b side of the excavation hole 13 and is press-fitted to the screw portion 6 to form the columnar foundation 21, so that the excavated earth and sand are not carried out to the ground during excavation. Pressed outward to consolidate hole wall 13a The columnar base body 21 can be easily Construction and easily supply only replenishing material 4 sand or gravel it is Rukoto, can be simplified in structure and operations.

  The screw portion 6 is provided with a check valve 17 that prevents the earth and sand excavated during the forward rotation from being taken into the casing 3 and allows supply of the replenishment material 4 from the casing 3 to the excavation hole 13 during the reverse rotation. Therefore, the ground G can be excavated during the forward rotation of the screw part 6 and the excavated earth and sand can be pushed into the hole wall 13a without being taken into the casing 3, and can be consolidated. It is possible to easily form the columnar foundation 21 by pushing the replenishment material 4 filled into the hole bottom 13b side and the hole wall 13a side.

  Further, since a hopper 20 for introducing the replenishment material 4 into the casing 3 from the opening 5 near the ground G is installed on the ground G around the casing 3, a bucket crane or the like is not used. The replenishment material 4 can be easily supplied to the hopper 20 and the remaining amount of the replenishment material 4 in the hopper 20 can be easily confirmed visually.

  Further, a non-hole portion 7 not having the opening 5 is formed in a predetermined range on the outer peripheral surface on the lower end side of the casing 3 in order to prevent inflow and circulation of excavated earth and sand into the casing 3 during excavation. Therefore, it is possible to prevent a situation in which it becomes difficult to push the excavated earth and sand into the hole wall 13a when the excavated earth and sand flows from the opening 5 and circulates.

  The embodiments of the present invention have been described in detail with reference to the drawings. However, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the gist of the present invention. . For example, instead of the hopper 20, a plate material such as a steel plate may be placed on the ground, the supply material 4 may be placed, and the supply material 4 may be thrown into the casing 3 through the opening 5 while being scraped by a scoop or the like. .

  In addition, the casing may be formed in a rectangular tube shape in order to suppress a problem that the excavated earth and sand enters the casing 3 and adheres to the inner wall of the casing to hinder the rotation of the spiral blade. Further, as shown in FIG. 6, the compaction part is provided at the tip of the rotary shaft 8, and the ground can be excavated by forward rotation, and the sand from the transport part is removed by reverse rotation and the bottom side of the excavation hole and You may have the consolidation cam (consolidation part) 30 which has an at least 2 cam surface pressed in radial direction outward and is consolidated. Further, the spiral blade 16 may be provided continuously along the longitudinal direction of the rotating shaft 8. Thereby, the replenishment material 4 thrown in in the casing 3 from the hopper 20 through the opening part 5 can be smoothly conveyed below.

  The consolidation cam 30 is composed of two cam plates 31 and 31 having a circular arc shape and a side inverted triangle. The cam plates 31 and 31 are formed, for example, by cutting the side surface of a large-diameter steel pipe into a triangular shape. Has been. The two cam plates 31, 31 are disposed so as to sandwich the rotating shaft 8 at the tip portion of the rotating shaft 8 with the inner sides facing each other, and are symmetrically displaced with respect to the rotating shaft 8 from side to side. It is being fixed to the rotating shaft 8 in the state. As a result, when the consolidation cam 30 is rotated in the clockwise direction (arrow A) (forward rotation), the ground G is excavated by the inner surface 31x of the laterally protruding portion 31a of the cam plates 31 and 31 protruding outward in the radial direction. On the contrary, when the consolidation cam 30 is rotated counterclockwise (arrow B) (reverse rotation), the sand is moved downward and tangentially or radially outwardly by the outer surface 31y of the side protrusion 31a of the cam plates 31, 31. It can be pressed and consolidated. The cam plate 31 is preferably integrally fixed to the rotary shaft 8 by welding or the like, but may be detachably attached by a coupling means such as a bolt and a nut.

DESCRIPTION OF SYMBOLS 1 Ground compaction apparatus 2 Working machine 3 Casing 4 Supply material 5 Opening part 7 Screw part 8 Rotating shaft 9 Rotation drive part 10 Lifting hook 11 Locked part 12 Lead part 13 Excavation hole 14, 15 Blade member 16 Spiral blade 17 Reverse Stop valve 18 Hinge 19 Valve body 20 Hopper 21 Columnar foundation

Claims (4)

The base end is supported by the work machine so that it can be raised and lowered, and a plurality of openings are formed on the peripheral wall at appropriate intervals in the circumferential direction and the axial direction for supplying replenishing materials such as sand, gravel or aggregate and solidified material. A cylindrical casing, a rotary shaft that is inserted along the axial center in the casing and rotated forward or reversely by a rotation drive unit provided at a base end portion of the casing, and a distal end portion of the rotary shaft. Excavating the ground by forward rotation and consolidating the excavated earth and sand toward the hole wall; and by consolidating the replenishment material in the casing into the hole bottom side of the excavation hole by reverse rotation and forming a columnar foundation A ground compaction apparatus provided , wherein the opening is formed in a honeycomb shape in which the gap between the openings is narrowed in the peripheral wall of the casing and the position of the vertical rib between the openings is sequentially changed in the circumferential direction in the axial direction of the casing. On the ground around the front Ground compaction device hopper for introducing the replenishment material through the opening in the casing, characterized in that it is placed. The consolidated portion has two semi-disc shaped blade members intersecting in an X shape when viewed from the side with respect to the rotation axis, and lower end edges opposite to each other as viewed from above than the casing. It consists of a screw part provided so as to protrude outward, and is arranged between one upper edge part and the other lower edge part of the two blade members and swings to the upper edge part via a hinge. is rotatably droop, and closed during forward rotation of the rotary shaft to prevent the uptake of excavation soil into the casing, the supply of opened during reverse rotation of the rotary shaft replenishment material from the casing to the wellbore 2. The ground compaction device according to claim 1, further comprising a check valve made of a plate-shaped valve body that is allowed. The hopper includes an annular or arc-shaped leg portion placed on the upper surface of the ground, an annular or planar arc-shaped rising portion that rises from the leg portion, and an annular shape that is formed with a diameter increasing upward from the rising portion. The ground compaction device according to claim 1 , further comprising a flat arcuate hopper portion .   A non-perforated portion that does not have the opening in a predetermined range is formed on the outer peripheral surface of the front end side of the casing in order to prevent inflow and circulation of excavated earth and sand into the casing during excavation. The ground compaction device according to claim 1.