JP2007177445A - Supporting equipment for caisson-bottom excavator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the technology of using an excavator, which excavates a section below a caisson skeleton in a bottom hole, capable of being hardly excavated by a clamshell, in the state of fixing the excavator to an inner surface of a caisson at any time, in an open caisson sinking method. <P>SOLUTION: A covering body 52 is temporarily attached in a sucked manner to an inner surface of a steel plate 12 by sucking the atmosphere inside the covering body 52 by means of a suction unit 53; a jet of pressure water is emitted into the covering body 52 from a pressure water blowoff device 54, so that mud 60 on the inner surface of the steel plate 12 in the covering body 52 can be removed; removed muddy water is discharged by a discharge device 55; the supply of electric power to an electromagnetic device 51 from a power source 511 makes an electromagnetic device 51 attached to the cleaned inner surface of the steel plate 12 by an attractive force; and an excavating force of the excavator 40 is borne by it. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a support device for an excavator that excavates the lower caisson floor, and more specifically, supports the reaction force of an excavator used for excavating the ground of the lower caisson bottom, which is difficult to drill with a clam shell, in the vicinity of the lower end of the caisson housing. This is related to the supporting device to be operated.

  Conventionally, an open caisson press-fitting method is known as a method for constructing a foundation such as a pier or a large-scale underground structure by laying an RC or PC caisson in the bottom of the water or in the ground. This open caisson press-fitting method uses a jack with a ground anchor to support the reaction force by excavating the ground in the box with a clamshell while sequentially stacking the caisson housing on top of the caisson housing having the blade edge at the lower end. It overcomes the resistance and frictional force of the outer periphery of the caisson and presses and sinks the caisson into the ground.

  However, the excavation of the ground by the clamshell is the maximum extent of excavation in a range approximately equal to the range enclosed by the inner surface of the caisson, and the ground at the bottom of the caisson is difficult to excavate by the clamshell. Therefore, when the ground where the caisson is pressed and subsidized is soft ground, even if unexcavated soil exists at the bottom of the caisson, the caisson can be pressed and subsidized by the above-described open caisson press-in method, but the caisson is pressed. If hard ground such as bedrock appears at the bottom of the caisson during the process, the unexcavated soil at the bottom of the caisson may become a resistance, and the caisson may not be able to be pressed and settled.

  As a device to cope with such problems, it consists of a mounting base that moves along a rail installed horizontally on the inner wall of the lower part of the caisson that has been press-fitted and submerged, and an excavator attached to this mounting base. An excavation apparatus has been proposed that excavates the ground below the caisson by an excavator that is remotely operated from the ground while moving the mounting base along (see, for example, Patent Document 1).

According to the excavator that supports the reaction force on such a caisson housing, it is possible to excavate the ground below the caisson, which is difficult to excavate with a clam shell. Even if hard ground such as bedrock appears at the bottom of the caisson during the press-fitting process, the caisson can be reliably press-fitted and submerged by excavating the hard ground.
Japanese Patent No. 2717874

  However, in the excavator described above, the rail on which the mounting base for mounting the excavator needs to be installed in the caisson beforehand, and when excavating the ground in the box with a clamshell, it is installed on the lower inner wall surface of the caisson. There is a risk of clamshell grab buckets coming into contact with and colliding with the damaged rails and damaging the rails.

  In view of the above circumstances, an object of the present invention is to provide a support device for a caisson lower bottom excavator that does not require a rail or the like to be attached in advance to the inner wall surface of the caisson.

  The support device for the caisson lower bottom excavator of the present invention that achieves the above object is the excavator support device for excavating the ground of the caisson lower bottom by supporting the reaction force on the caisson housing, and a steel plate is attached to the inner wall near the lower end. The caisson housing is used, and the support device includes an electromagnet device that adsorbs and desorbs on the inner surface of the steel plate, a positioning control device for the electromagnet device, and a lifting device.

  The support device for the caisson lower bottom excavator of the present invention is configured such that the electromagnet device attracted to the inner surface of the steel sheet by supplying electric power positions the excavator and supports the excavation reaction force. Since it separates, it is not necessary to previously attach members, such as a rail which supports the reaction force of an excavator, to the inner wall surface of a caisson. Therefore, according to the support device for the caisson lower bottom excavator of the present invention, when the excavator for excavating the ground of the caisson lower bottom difficult to excavate with the clamshell is pulled up, the suspended excavator is pulled up. There is no obstacle such as a rail protruding inside the caisson, and the rail or the like is prevented from being damaged by a grab bucket or the like.

  Here, the support device for the caisson lower bottom excavator according to the present invention includes a covering body that includes the electromagnet device and partially covers the inner surface of the steel plate, and sucks an atmosphere inside the covering body to thereby cover the covering body. It is preferable to include a suction device for temporarily adsorbing the steel plate to the inner surface of the steel plate, a pressure water jetting device for cleaning mud on the inner surface of the steel plate in the covering, and a discharge device for discharging the cleaned mud water.

  Here, the “atmosphere” referred to in the present invention refers to a gas or liquid existing in the internal space of the covering that partially covers the inner surface of the steel plate.

  In this way, by sucking the atmosphere inside the covering body to temporarily adsorb the covering body and cleaning the mud on the inner surface of the steel sheet in the covering body, the electromagnet device built in the covering body is reliably and largely attached to the inner surface of the steel sheet. It can be adsorbed by adsorption force.

  However, when the attracting force by the electromagnet device is superior to the force that impedes the attracting by the mud on the inner surface of the steel plate in the covering, it is not particularly necessary to remove the mud.

  The caisson lower-bottom excavator support device of the present invention includes a plurality of the support devices and a back surface including an arc-shaped rail connecting the plurality of support devices, and the rail is a support portion on which the excavator is mounted. It is also a preferable form.

  According to the support device for the caisson bottom bottom excavator equipped with such a rail, it is possible to excavate a wide range of ground by moving the excavator along the rail without changing the adsorption position by the electromagnet device. it can.

  According to the support device for the caisson bottom bottom excavator of the present invention, since the electromagnet device that is adsorbed and desorbed on the inner surface of the steel sheet by supplying and interrupting electric power positions the excavator and supports the excavation reaction force, the excavator is not used. Occasionally there are no obstacles such as rails protruding inside the caisson, rails etc. are not damaged by grab buckets etc., and an excavator with a caisson housing supporting the reaction force is used effectively from time to time I was able to do it.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a longitudinal sectional view showing an open caisson press-fitting method for sinking the caisson 10 using a support device 50 to which an embodiment of the present invention is applied. FIG. 1 shows the state of the press-fitting process in which the caisson 10 is press-fitted and submerged in the ground.

  The lowermost caisson housing of the caisson 10 has a blade edge 11 at the lower end, and a steel plate 12 is attached to the inner wall over a range from the lower end of the inner wall near the blade edge 11 to a height of about 3 m. A segment block is added to the top of the caisson housing, or a caisson housing constructed by in-situ reinforced concrete is stacked on the top of the caisson housing. A plurality of ground anchors (not shown) are driven into the ground and fixed to the ground 100. The ground in the box is excavated with a clamshell grab bucket 70 and a jack (not shown) is used to counteract the ground anchor and overcome the edge resistance and the frictional force of the outer peripheral surface of the caisson 10 to press the caisson 10 into the ground. Let it sink.

  In this press-fitting process, when hard ground such as bedrock appears in the lower bottom of the caisson 10 and the caisson 10 is difficult to press-sink, the caisson lower-bottom excavator 20 is loaded from the ground as shown in FIG. The caisson 10 is lowered while the caisson 10 is excavated by using the caisson lower bottom excavator 20, such as the ground 13 at the lower bottom of the caisson 10.

  The caisson 10 is set in the ground 100 from the ground along the planned sinking line 14, and sinks deep below the water level 15.

  The caisson lower bottom excavator 20 is suspended from the ground by a wire 93 of a crane 92 and is lifted and lowered as necessary. The positioning control device 94 controls the suction position of the support device 50 that supports the caisson lower bottom excavating device 20. The crane 92 is an embodiment of the lifting device of the present invention, the positioning control device 94 is an embodiment of the positioning control device of the present invention, and the support device 50 is the caisson lower bottom excavator of the present invention. It is an Example of a support apparatus.

  The caisson lower bottom excavator 20 includes a support device 50, a frame 30 attached to the support device 50, and an excavator 40. The support device 50 adsorbs to the inner surface of the steel plate 12 attached to the inner wall near the lower end of the caisson 10 to position the excavator 40 and supports the excavation reaction force. The excavator 40 is attached to the frame 30 and excavates the ground 13 at the lower bottom portion of the caisson 10 by swinging between the vertical drooping position and the caisson blade edge 11. This combination of the frame 30 and the excavator 40 is an embodiment of the excavator of the present invention. The caisson lower bottom excavator 20 is supplied with high-pressure hydraulic pressure from a hydraulic device 90 provided on the ground through a hydraulic pressure supply pipe 91 to swing the excavator 40 and drive the excavator 40 to rotate.

  Next, with reference to FIGS. 2-4, the Example of the support apparatus of the caisson lower bottom excavator of this invention is explained in full detail.

  2 is a side view of the state where the caisson lower bottom excavator 20 shown in FIG. 1 is temporarily adsorbed on the inner surface of the steel plate 12, and FIG. 3 is a side view of the state where the caisson lower bottom excavator 20 is adsorbed on the inner surface of the steel plate 12. FIG. 4 and FIG. 4 are front views of the caisson lower bottom excavator 20.

  As shown in FIGS. 2 to 4, the caisson lower bottom excavator 20 includes two support devices 50, and two arc-shaped rails 80 made of H-shaped steel that connect the two support devices 50 to each other on the back surface. I have. A frame 30 is suspended from the arc-shaped rail 80, and an excavator 40 that swings between the vertical drooping position and the caisson blade edge is mounted on the frame 30. This arc-shaped rail 80 is an embodiment of the arc-shaped rail of the present invention.

  Each support device 50 includes an electromagnet device 51, a covering 52, a suction device 53, a pressure water ejection device 54, and a discharge device 55, respectively.

  The electromagnet device 51 is attracted to the inner surface of the steel plate 12 when power is supplied from the power source 511 via the power cable 511a, and detached from the inner surface of the steel plate 12 when power from the power source 511 is cut off. The electromagnet device 51 has a recess 51a on the surface of the electromagnet device 51 that is adsorbed and desorbed on the inner surface of the steel plate 12, and a coil spring 512 is incorporated in the recess 51a. This electromagnet device 51 is an embodiment of the electromagnet device of the present invention. In the present embodiment, the electromagnet device 51 having a maximum attractive force of 100 KN is used.

  The covering body 52 incorporates an electromagnet device 51 rigidly coupled to the covering body 52 and partially covers the inner surface of the steel plate 12 via an elastic member 56. This covering 52 is an example of the covering of the present invention.

  The suction device 53 sucks the atmosphere inside the covering 52 through the suction pipe 531 and temporarily adsorbs the covering 52 to the inner surface of the steel plate 12. In the state where the support device 50 is temporarily attracted in this way, one end of the coil spring 512 incorporated in the concave portion 51a of the electromagnet device 51 comes into contact with the inner surface of the steel plate 12 facing the electromagnet device 51 as shown in FIG. A space is maintained between the electromagnet device 51 and the inner surface of the steel plate 12. The atmosphere here refers to a gas or liquid existing in the internal space of the covering 52 that partially covers the inner wall surface of the caisson 10. This suction device 53 is an embodiment of the suction device of the present invention.

  The pressure water ejecting device 54 cleans the mud 60 on the inner surface of the steel plate 12 in the covering 52 by ejecting pressure water into the covering 52 via the pressure water ejecting pipe 541. The cleaned muddy water is sucked and discharged by the discharge device 55 through the discharge pipe 551. The pressure water ejection device 54 is an embodiment of the pressure water ejection device of the present invention, and the discharge device 55 is an embodiment of the discharge device of the present invention.

  As shown in FIG. 2, the supporting device 50 configured in this way first sucks the atmosphere inside the covering 52 by the suction device 53 to temporarily adsorb the covering 52 on the inner surface of the steel plate 12, and ejects pressure water. Pressure water is ejected from the device 54 into the covering 52 to clean the mud 60 on the inner surface of the steel plate 12 in the covering 52, and the cleaned mud is discharged by the discharging device 55. However, when the attraction force by the electromagnet device 51 exceeds the force that inhibits the attraction of the inner surface of the steel sheet 12 in the covering 52 by the mud, the mud does not have to be removed by cleaning.

  Thereafter, as shown in FIG. 3, the excavating force of the excavator 40 can be supported by attracting the electromagnet device 51 to the cleaned inner surface of the steel sheet 12 by supplying power from the power source 511 to the electromagnet device 51. . Further, by pressing the electromagnet device 51 on the cleaned inner surface of the steel plate 12, the support device 50 can be reliably adsorbed to the inner surface of the steel plate 12 with a large adsorption force. The coil spring 512 incorporated in the recess 51a of the electromagnet device 51 is housed in the recess 51a when the electromagnet device 51 is attracted to the inner surface of the steel plate 12.

  Two arc-shaped rails 80 made of H-shaped steel connecting the two support devices 50 provided on the back surface of each support device 50 are connected to the upper and lower arc-shaped rails 80 by a vertical connecting member 81. Each arc-shaped rail 80 has an inner flange 80a and an outer flange 80b. The vertical connecting member 81 and the inner flange 80a are rigidly connected to the back surface of each support device 50, and the outer flange 80b functions as a rail. Further, the upper arc-shaped rail 80 of the upper and lower two arc-shaped rails 80 includes a crane wire coupling portion 80 c and is suspended from the ground by the wire 93 of the crane 92. A rack 82 is provided on the side surface of the outer flange 80 b of the lower arc-shaped rail 80.

  The frame 30 includes eight upper and lower wheels 31 suspended from the upper and lower arc-shaped rails 80 and a pinion gear 83 that meshes with a rack 82 provided on the side surface of the outer flange 80 b of the lower arc-shaped rail 80. When the pinion gear 83 is driven, the frame 30 turns along the arcuate rail 80. A crane wire coupling portion 32 is provided at the upper end of the frame 30 and is suspended from the ground by a wire 93 of a crane 92. Further, the excavator 40 is suspended from the lower end of the frame 30 by a bracket 46 and a connecting pin 43.

  The frame 30 is firmly formed by frame members 33, 34, and 36 such as H-shaped steel and side plates, and necessary portions of the connecting portion are made flexible by pins 35 and the like. In addition, a hydraulic cylinder 47 that swings the excavator 40, a shock absorber 48, and the like are provided.

  The excavator 40 may use, for example, a device having rotating screw blades, and the length thereof is long enough to excavate the ground 13 in the portion up to the blade tip under the caisson blade edge. Is established. Thus, by determining the swing angle of the excavator 40, the excavation range can be excavated appropriately without waste. In this embodiment, an apparatus having a rotating shaft (screw blade shaft) 41 having screw blades 42 is shown as the excavator 40. The model of the excavator 40 is not limited to this embodiment, and any excavator may be used. For example, instead of screw blades, a device having a rotating shaft with a large number of projecting rods or blades attached, a device having a propeller or impeller, rotating and reciprocating, a drilling and drilling device using high pressure fluid, a combination of these devices, etc. Good.

  The rotation drive unit 45 rotates the screw blade shaft 41.

  The excavator 40 is coupled to and suspended from the frame 30 by a bracket 46 and an eccentric coupling pin 43. The excavator 40 is driven to swing by a hydraulic cylinder 47 attached to the frame 30. The ram of the hydraulic cylinder 47 is coupled to the head pin 44 of the excavator 40. The excavator 40 is driven to swing by the expansion and contraction of the ram of the hydraulic cylinder 47.

  As described above, according to the support device 50 of the embodiment, the caisson lower bottom excavating device 20 that is suspended when the excavator 40 that excavates the ground 13 at the lower bottom portion of the caisson 10 that is difficult to excavate with a clamshell is not used. As a result, the obstacles such as the rails protruding inside the caisson 10 do not exist, and the rails and the like are prevented from being damaged by the grab bucket 70 or the like.

  In addition, when caisson 10 press-fit process, hard ground such as bedrock appears at the bottom of caisson 10, and when it is necessary to excavate the hard ground using an excavator, caisson bottom bottom excavator 20 is lowered. The excavator 40 is positioned by the support device 50 including the electromagnet device 51 that is adsorbed to and desorbed from the inner surface of the steel sheet 12 by supplying and interrupting electric power, and the excavation reaction force is strongly supported, so that the excavator 40 is effectively effective as needed. Can now be used.

  Further, in the support device 50 of the embodiment, since the support device 50 includes the arc-shaped rail 80 and the frame 30 on which the excavator 40 is mounted travels along the arc-shaped rail 80, the adsorption position by the electromagnet device 51 is changed. A wide range of ground can be excavated by moving the excavator 40 without doing so.

  In the above-described embodiment, an example in which two support devices of the present invention are provided has been described. However, the support device of the present invention may be one or more than two.

  In the above-described embodiment, an example in which the back surface of the support device of the present invention is provided with the arc-shaped rail and the excavator is mounted on the rail has been described, but the present invention is not limited to this, and the present invention is not limited thereto. An excavator may be rigidly coupled to the support device.

It is a longitudinal cross-sectional view which shows the open caisson press-fit method which sinks a caisson using the support apparatus with which one Embodiment of this invention was applied. It is a side view of the state where the caisson lower bottom excavator shown in FIG. It is a side view of the state which made the caisson lower bottom excavator shown in FIG. 1 adsorb | suck to the steel plate inner surface. It is a front view of the caisson lower bottom excavator shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Caisson 11 Cutting edge 12 Steel plate 13 Ground 14 Planned settlement line 15 Water level 20 Caisson lower bottom drilling device 30 Frame 31 Wheel 32 Crane wire coupling part 33, 34, 36 Frame member 35 Pin 40 Excavator 41 Rotating shaft (screw blade shaft) )
42 Screw blade 43 Coupling pin 44 Head pin 45 Rotation drive unit 46 Bracket 47 Hydraulic cylinder 48 Shock absorber 50 Support device 51 Electromagnet device 51a Recessed portion 511 Power source 511a Power cable 512 Coil spring 52 Cover body 53 Suction device 531 Suction tube 54 Pressure water jet Device 541 Pressure water jet tube 55 Discharge device 551 Discharge tube 56 Elastic member 60 Mud 70 Grab bucket 80 Arc-shaped rail 80a Inner flange 80b Outer flange 80c Crane wire coupling portion 81 Vertical connecting member 82 Rack 83 Pinion gear 90 Hydraulic device 91 Hydraulic supply tube 92 Crane 93 Wire 94 Positioning Control Device 100 Ground

Claims (3)

  In a support device for an excavator that excavates the ground at the bottom bottom of the caisson by supporting a reaction force on the caisson housing, a caisson housing in which a steel plate is attached to the inner wall near the lower end is used, and the support device is an electromagnet that is adsorbed and desorbed on the inner surface of the steel plate. A support device for a caisson lower bottom excavator, comprising: a device, a positioning control device for the electromagnet device, and a lifting device.   A covering body containing the electromagnet device and partially covering the inner surface of the steel sheet; a suction device for sucking the atmosphere inside the covering body and temporarily adsorbing the covering body to the inner surface of the steel sheet; and an inner surface of the steel sheet in the covering body The support device of the caisson bottom bottom excavator according to claim 1, further comprising: a pressure water jetting device for cleaning the mud of soil and a discharging device for discharging the cleaned mud water.   The caisson lower bottom excavation according to claim 1, wherein a plurality of said support devices are provided, and arc-shaped rails connecting the plurality of support devices are provided on the back surface, and the rails are support portions to which excavators are attached. Support device for the machine.

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