JP2015175201A - Drilling machine, drilling method, and cleaning method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drilling machine that can reliably wash slime accumulated on joints of a pile hole and discharge it to the ground.SOLUTION: A drilling machine 1, which is used for a reverse circulation type drilling method and configures a pile hole 25 by drilling soil while sucking drilled sediment with mud and discharging them to the ground, comprises a drilling machine body 2 with a suction pump 9 and a suction pipe 10 for sucking drilled sediment with mud and discharging them to the ground, and a cleaning means 11, which is branched from the suction pipe 10 and ejects in the lateral direction a part of mud 30 sucked by the suction pump 9, is provided on a part of the drilling machine body 2.

Description

  The present invention relates to an excavator, an excavation method, and a cleaning method, and more particularly, to an excavator, an excavation method, and a cleaning method in a reverse circulation excavation system.

  As a method of constructing a pile hole for a wall-like underground structure with a knot, a pile hole is constructed by excavating the ground with an excavator and discharging the excavated earth and sand together with mud water to the ground with a suction pump. A drilling method using a reverse circulation method (hereinafter referred to as “reverse circulation method”) is known.

  An example of the reverse circulation excavation method is shown in FIG. For example, a hydrophrase excavator (hereinafter referred to as “HF excavator 1”) is used to construct a pile hole for a wall-like underground structure with a knot by this excavation method, as shown in FIG. Then, the excavator main body 2 of the HF excavator 1 is lowered toward the ground, and the cutter drum 7 at the lower end of the frame 3 of the excavator main body 2 is rotated to excavate the ground while supplying the stable liquid from the ground. By driving the suction pump 9 at the lower end of the frame 3 and discharging the excavated earth and sand together with the muddy water to the ground through the suction pipe 10, the shaft portion 26 of the rectangular cross-sectional pile hole 25 reaching the support layer is formed.

  Next, as shown in FIG. 4 (b), the excavator body 2 of the HF excavator 1 is removed from the pile hole 25, and an earth drill excavator (hereinafter referred to as ED excavator 22) is placed in the pile hole 25. The widening bucket 23 is inserted and the widening bucket 23 is driven to rotate, so that the wall surface 26a of the shaft portion 26 of the pile hole 25 is excavated and widened, and the node portion 27 is provided at the intermediate portion of the shaft portion 26 of the pile hole 25. Form.

  Next, as shown in FIG. 4C, the widening bucket 23 of the ED excavator 22 is removed from the pile hole 25, and the slime cleaner 31 is inserted into the pile hole 25.

  Next, as shown in FIG. 4D, the slime cleaner 31 is positioned at the position of the node portion 27 of the pile hole 25, and the slime cleaner 31 is driven, so that the muddy water 30 in the pile hole 25 is removed from the slime cleaner 31. The slime water 30 is sucked into the slime cleaner 31 from the lower suction port 32 and sprayed from the discharge port 33 at the upper end of the slime cleaner 31 toward the node 27. Thereby, the slime 28 deposited on the lower wall surface 27c of the node portion 27 can be washed out in the pile hole 25, and the lower wall surface 27c of the node portion 27 can be in a clean state in which the slime 28 is not deposited.

  Next, as shown in FIGS. 4 (e) and 4 (f), the slime cleaner 31 is removed from the pile hole 25, the excavator body 2 of the HF excavator 1 is inserted into the pile hole 25, and the excavator body 2 is lowered to the bottom of the pile hole 25. Then, while supplying the stabilizing liquid from the ground into the pile hole 25, the suction pump 9 is driven, and the excavated sediment is discharged to the ground through the suction pipe 10 together with the muddy water, thereby accumulating at the bottom of the pile hole 25. The muddy water 30 containing the slime 28 is discharged to the ground, and the muddy water 30 containing the slime 28 in the pile hole 25 is replaced with a high-quality stabilizer.

  By the way, in the excavation method as described above, the excavator main body 2 of the HF excavator 1 is inserted into the pile hole 25 and removed (FIG. 4A), and the widening bucket 23 of the ED excavator 22 is removed. Is inserted into the pile hole 25 and removed (FIG. 4 (b)), the slime cleaner 31 is inserted into the pile hole 31 and removed (FIG. 4 (c), (d)), HF excavator The process (FIG.4 (e), (f)) which inserts the 1 excavator main body 2 in the pile hole 25 is needed.

  For this reason, while the number of processes as a whole increases, it takes a long time to wash away and remove the slime 28 deposited on the lower wall surface 27c of the node 27 of the pile hole 25, and the entire construction period becomes longer. In addition, since the number of facilities to be used increases, the cost of facilities increases, and a large space is required to install many facilities, so that applicable sites are limited.

  Further, since the slime cleaner 31 is not provided with a mechanism for holding the slime cleaner 31 in the pile hole 25, when the muddy water 30 is sprayed from the slime cleaner 31 toward the lower wall surface 27c of the node 27, The slime cleaner 31 is shaken by the injection pressure of the muddy water 30, and the slime 28 deposited on the lower wall surface 27 c is completely washed away without causing the injected muddy water 30 to hit the lower wall surface 27 c of the node 27 accurately. The slime 28 may remain on the lower wall surface 27c.

  By the way, Patent Literature 1 describes a slime removing device that removes slime deposited on a node portion (expanded diameter portion) of a pile hole. The slime removing device includes an annular donut pipe, a plurality of stable liquid injection pipes connected to the donut pipe via a swivel joint, and a stable liquid supply hose connecting between the donut pipe and the ground stable liquid supply pump. And a plurality of wires for suspending the donut tube, and a suspension for supporting the wires.

  In order to remove the slime accumulated in the joints of the pile hole using the slime removing device having such a configuration, after installing the reinforcing bar in the pile hole constructed in the ground, the lifting device of the slime removing device from the ground By manipulating the wire via, the inner diameter portion of the reinforcing bar is lowered while the donut tube is kept horizontal and positioned at the node portion of the pile hole, and each stable liquid injection tube enters the node portion.

  Then, the stable liquid is supplied to the donut pipe from the stable liquid supply pump on the ground through the stable liquid supply hose, and the stable liquid is ejected from the respective stable liquid injection pipes toward the wall surface of the node through the donut pipe. Wash off the slime and deposit it on the bottom of the pile hole. And the mud containing the slime deposited on the bottom of the pile hole is discharged to the ground, and then the slime removing device is removed to the ground.

Japanese Patent No. 3772250

  Since the slime removal apparatus described in the above-mentioned patent document 1 has washed the slime accumulated in the joints of the pile hole in a state where the reinforcing bar is built in the pile hole, There is a risk of sticking to the reinforcing bars.

  In addition, the stable liquid injection pipe is connected to the donut pipe through a swivel joint and is configured to be rotatable in the vertical direction with respect to the donut pipe, so that when the stable liquid is injected from the stable liquid injection pipe The stable liquid spray pipe moves up and down due to the spray pressure, so that the stable liquid cannot be reliably sprayed onto the wall surface of the node, and slime may remain on the wall surface of the node.

  In addition, since the donut pipe is connected to the stable liquid supply hose, it can be held to some extent in the predetermined position in the pile hole, but if the stable liquid supply hose is flexible, Since the donut tube sways in the pile hole due to the injection pressure when the stable liquid is injected, the stable liquid can be reliably sprayed to the joint of the pile hole as in the conventional technique described with reference to FIG. There is also a problem that it cannot be done.

  Furthermore, the mud containing the slime washed off at the bottom of the pile hole is sucked up by the suction pipe passing through the inner diameter side of the reinforcing rod and discharged to the ground, so it is difficult to absorb the slime accumulated at the bottom of the pile hole. The slime may remain at the bottom of the pile hole.

  The present invention has been made in view of the conventional problems as described above, and the construction period as a whole can be shortened by reducing the number of steps when constructing a pile hole having a node portion. At the same time, the object is to ensure that the slime deposited on the joint can be washed off and discharged to the ground.

In order to solve the above problems, the present invention employs the following means.
That is, the present invention is an excavator used in a reverse circulation type excavation method in which a pile hole is constructed by sucking up excavated sediment with mud and discharging it to the ground while excavating the ground. An excavator body having a suction pump and a suction pipe to be discharged to the ground, and a part of the mud water that is branched from the suction pipe and sucked up by the suction pump to the side of the excavator body. It is characterized in that a cleaning means is provided for spraying toward the surface.

  According to the excavator of the present invention, a part of the excavator body that constructs the pile hole is provided with cleaning means for injecting a part of the muddy water sucked from the pile hole by driving the suction pump to the side. With the excavator body suction pump, the mud containing the slime collected at the bottom of the pile hole is discharged to the ground, and the slime deposited on the wall surface of the pile hole node by the muddy water sprayed by the cleaning means Can be washed off. Therefore, since it is not necessary to use a slime cleaner to wash off the slime deposited on the wall surface of the pile hole node, the number of processes can be reduced as a whole, and the slime deposited on the wall surface of the pile hole node The time required for washing off can be shortened, and the construction period as a whole can be shortened.

  Further, in the present invention, the excavator body includes a rectangular columnar frame, a cutter drum rotatably provided at a lower end of the frame, the suction pump provided at a lower end portion of the frame, and an inner side of the frame. It is good also as providing the said suction pipe which connects between the said suction pump and the ground while being provided, and having provided the said washing | cleaning means in the part below the upper end or the upper end of the said flame | frame.

  According to the excavator of the present invention, the excavator body is inserted into the pile hole, the excavator body is lowered in the pile hole, and the cleaning means is positioned at a position corresponding to the node of the pile hole. In this case, the suction pump is driven to suck up the muddy water in the pile hole, so that a part of the muddy water is supplied to the cleaning means branched from the suction pipe, and the muddy water is directed from the cleaning means toward the wall surface of the pile hole. The slime deposited on the wall surface is washed away in the pile hole.

  Further, in the present invention, the cleaning means is fixed to the frame, and a rectangular annular injection pipe in which a plurality of injection holes are provided in a portion facing the wall surface of the nodal part of the pile hole, and the injection pipe It is good also as providing the branch pipe which connects between the said suction pipes, and the opening-and-closing valve which opens and closes between this branch pipe and the said suction pipe.

  According to the excavator of the present invention, by driving the suction pump with the opening / closing valve of the cleaning means opened, a part of the muddy water sucked up from the pile hole through the suction pipe is injected from the suction pipe through the branch pipe. It is supplied to the pipe, sprayed from the injection hole of the injection pipe toward the wall surface of the node of the pile hole, and the slime accumulated on the wall surface is washed away in the pile hole.

  In addition, the present invention provides a rectangular cross section by excavating the ground with a hydrophrase excavator, driving a suction pump while supplying a stable liquid from the ground, and discharging excavated earth and sand together with muddy water to the ground. Forming the shaft portion of the pile hole, removing the hydrophrase excavator from the pile hole, inserting an earth drill excavator into the pile hole, and driving the earth drill excavator, A step of forming a node portion in an intermediate portion of the shaft portion of the pile hole, removing the earth drill excavator from the pile hole, inserting the hydrophrase excavator into the pile hole, and driving the suction pump In this way, the muddy water is sucked up from the borehole through the suction pipe, and a part of the muddy water is branched from the suction pipe and used for cleaning means. Then, the step of washing the slime deposited on the wall surface by spraying from the washing means toward the wall surface of the node, and the supply of muddy water to the washing means are stopped, and the pile hole is stabilized from the ground. By repeatedly discharging the excavated earth and sand together with the mud while supplying the liquid, the mud containing the slime accumulated at the bottom of the pile hole is discharged to the ground, and the mud containing the slime in the pile hole has a good quality. And a step of replacing with a stabilizing solution.

  Further, the present invention is a cleaning method used for a reverse circulation excavation method for constructing a pile hole having a node by sucking excavated earth and sand together with mud and discharging it to the ground while excavating the ground, A part of the muddy water sucked up from the pile hole by the suction pump provided in the excavator main body of the excavator for excavating the water is sprayed toward the wall surface of the node portion to wash away the slime accumulated on the wall surface. It is characterized by that.

  As described above, according to the present invention, a dedicated slime cleaner for washing away slime deposited on the wall surface of the node of the pile hole becomes unnecessary. Therefore, when constructing a pile hole, the number of steps as a whole can be reduced, and the time required to wash off the slime deposited on the wall surface of the pile hole can be shortened, so the construction period as a whole can be shortened. . Moreover, since the slime deposited on the wall surface of the nodal part of the pile hole can be surely washed out in the pile hole, the quality of the structure constructed in the pile hole can be improved.

It is the schematic which shows the construction procedure of the pile hole for wall-shaped underground structures with a node as one embodiment of this invention. It is a principal part enlarged view of the excavator used in the construction procedure of FIG. It is explanatory drawing which showed the washing | cleaning state of the node part. It is the schematic which shows an example of the construction procedure of the pile hole for wall-shaped underground structures with a node in a prior art.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 3 show an embodiment of the present invention. This embodiment is applied to, for example, the construction of a pile hole 25 for a wall-like underground structure with a knot, and the pile hole 25 is constructed by discharging excavated earth and sand together with the muddy water 30 while excavating the ground. It is effective for the excavation method of the reverse circulation method (hereinafter referred to as “reverse circulation method”).

  The excavator 1 in the present embodiment is a hydrophrase excavator (hereinafter referred to as “HF excavator 1”), which includes a base machine (not shown) arranged on the ground, and a crane boom of the base machine. The excavator body 2 is suspended from the tip so as to be lifted and lowered.

  The excavator body 2 includes a rectangular columnar frame 3, a pair of cutter drums 7 rotatably provided at the lower end of the frame 3, and posture correcting means for correcting the posture of the frame 3 provided at the upper and lower ends of the frame 3 ( (Not shown), a suction pump 9 provided at the lower end of the frame 3, a suction pipe 10 connecting the suction pump 9 and a ground sediment separator (not shown), etc., and the upper end of the frame 3 The cleaning means 11 is provided.

  A columnar head portion 4 is provided at the center of the upper end of the frame 3 so as to protrude upward, and a sheave 5 is provided at the upper end of the head portion 4, and between the sheave 5 and the sheave on the crane boom side. The frame 3 is suspended from the tip of the crane boom by the wound wire 6.

  The cutter drum 7 has a built-in hydraulic motor, for example, and by lowering the excavator body 2 toward the ground by operating the base machine while rotating the cutter drum 7 by driving the hydraulic motor, A hole having a rectangular cross section (shaft portion 26 of the pile hole 25) is formed in the ground.

  The posture correcting means is a plate that adjusts the vertical degree of the frame 3 by extending and contracting in a pantograph manner and contacting the wall surface 26a of the shaft portion 26 of the pile hole 25. Both side surfaces 3c and 3d are provided so as to be extendable and contractible.

  One end of the suction pipe 10 is connected to the discharge port 9a of the suction pump 9 while being inserted through the inside of the frame 3, and the other end is connected to an earth and sand separator installed on the ground. By driving the suction pump 9, the excavated sediment in the pile hole 25 is guided to the ground sediment separator through the suction pipe 10 together with the muddy water 30.

  The cleaning means 11 includes an injection pipe 12 fixed to the upper end of the frame 3, a branch pipe 20 that connects the suction pipe 9 and the injection pipe 12, and an open / close that opens and closes the branch pipe 20 and the suction pipe 10. It consists of a valve 21.

  The injection pipe 12 is formed by bending the pipe so as to have substantially the same size as the frame 3 having a rectangular cross section, and is formed into a square ring shape. The first pipe portion is provided along the front surface 3a and the rear surface 3b of the frame 3. 13 and the second pipe portion 14, between the third pipe portion 15 and the fourth pipe portion 16 provided along the both side surfaces 3 c and 3 d of the frame 3, and between the first pipe portion 13 and the second pipe portion 14. The fifth pipe portion 17 and the sixth pipe portion 18 that connect each other, and the seventh pipe portion 19 that connects between the fifth pipe portion 17 and the sixth pipe portion 18.

  A branch pipe 20 branched from the suction pipe 10 is connected to a connection portion between the fifth pipe portion 17 and the seventh pipe portion 19 of the injection pipe 12, and a part of the muddy water 30 passes from the suction pipe 10 through the branch pipe 20. Supplied to the fifth pipe portion 17 of the injection pipe 12, supplied from the fifth pipe portion 17 to the first pipe portion 13 and the second pipe portion 14, or from the fifth pipe portion 17 to the seventh pipe portion 19 and the sixth pipe. The first pipe part 13 and the second pipe part 14 are supplied through the part 18.

  The on-off valve 21 is provided at a connection portion between the suction pipe 10 and the branch pipe 20 or a connection portion between the branch pipe 20 and the fifth pipe portion 17. The on-off valve 12 is not particularly limited as long as it is a type that can open and close the connecting portion, and may be a manual on-off valve 12 or an electromagnetic on-off valve 12.

  On the outer surfaces (the front surface 3a and the rear surface 3b side of the frame 3) of the first pipe portion 13 and the second pipe portion 14, there are a plurality of obliquely downward injection holes 13a, 14a at predetermined intervals in the length direction. A part of the muddy water 30 sucked up from the inside of the pile hole 25 is configured to be able to be injected from the injection holes 13a and 14a toward a node portion 27 of the pile hole 25 described later.

  The injection angles of the injection holes 13a and 14a are set so that the muddy water 30 can be uniformly injected over the entire lower wall surface 27c of the node 27 of the pile hole 25 described later. In the present embodiment, since the inclination angle of the lower wall surface 27c of the node 27 of the pile hole 25 is 45 ° with respect to the horizontal plane, the injection holes 13a and 14a are injected so as to face downward 45 °. An angle is set. Thereby, the muddy water 30 injected from the injection holes 13a and 14a can be applied perpendicularly to the lower wall surface 27c of the node portion 27, and thereby slime deposited on the lower wall surface 27c can be efficiently removed. . The injection angle of the injection holes 13a and 14a is not limited to the above angle, and may be set to an angle corresponding to the inclination angle of the lower wall surface 27c of the node 27 of the pile hole 25. The angle of jetting in a direction perpendicular to the angle.

  In order to construct the pile hole 25 for a wall-like underground structure with a knot using the HF excavator 1 of the present embodiment configured as described above, first, as shown in FIG. By operating the base machine of the HF excavator 1, the excavator body 2 is lowered toward the ground, the cutter drum 7 at the lower end of the frame 3 of the excavator body 2 is rotated, and the ground is excavated to stabilize the liquid from the ground. , The suction pump 9 at the lower end of the frame 3 is driven, and the excavated soil is discharged to the ground through the suction pipe 10 together with the muddy water 30 to form the shaft portion 26 of the rectangular cross-sectional pile hole 25 reaching the support layer. To do.

  Next, as shown in FIG. 1 (b), the excavator body 2 is pulled up and removed from the shaft portion 26 of the pile hole 25 by operating the base machine, and the earth drill excavator is inserted into the shaft portion 26 of the pile hole 25. By inserting the widening bucket 23 (hereinafter referred to as ED excavator 22) and rotating the widening bucket 23, the wall surface 26a of the shaft portion 26 of the pile hole 25 is excavated and widened. A node portion 27 is formed at an intermediate portion of the portion 26.

  Here, the node portion 27 has an upper wall surface 27a which is inclined downward and outward at a predetermined angle, a middle wall surface 27b which faces the lower end of the upper wall surface 27a and which faces the vertical direction, and a lower inner side which is continuous with the lower end of the middle wall surface 27b. The lower wall surface 27c is inclined at a predetermined angle. The lower wall surface 27c is set at an inclination angle of 45 ° with respect to the horizontal plane, and the slime 28 generated when the node portion 27 is constructed is deposited on the lower wall surface 27c.

  Next, as shown in FIGS. 1 (c) and 1 (d), the widening bucket 23 of the ED excavator 22 is pulled up and removed from the pile hole 25, and the excavator body 2 is operated by operating the base machine of the HF excavator 1. Is inserted again into the pile hole 25, the excavator body 2 is lowered in the pile hole 25, and the cleaning means 11 of the excavator body 2 is positioned at a position corresponding to the node 27 of the pile hole 25. In this case, an opening / closing valve 21 for opening / closing between the suction pipe 10 and the branch pipe 20 is opened in advance.

  And by supplying the stabilizing liquid from the ground to the pile hole 25 and driving the suction pump 9, the excavated earth and sand are discharged to the ground through the suction pipe 10 together with the mud water 30. At this time, a part of the mud water 30 is suctioned. From the pipe 10 to the injection pipe 12 through the branch pipe 20, the injection holes 13 a and 14 a of the first pipe portion 13 and the second pipe portion 14 of the injection pipe 12 are directed toward the lower wall surface 27 c of the node portion 27 of the pile hole 25. Let spray. As a result, the lower wall surface 27c of the node 27 is washed by the muddy water 30, the slime 28 deposited on the lower wall surface 27c is washed off into the pile hole 25, and the slim wall 28 is not deposited on the lower wall surface 27c. State.

  Next, as shown in FIG. 1 (e), the excavator body 2 is lowered to the bottom of the pile hole 25 by operating the base machine of the HF excavator 1, and a stable liquid is supplied into the pile hole 25 from the ground. While the suction pump 9 is driven and the mud 30 is discharged to the ground through the suction pipe 10 together with the mud 30, the mud 30 containing the slime 28 deposited at the bottom of the pile hole 25 is discharged to the ground. The mud 30 containing the slime 28 in the pile hole 25 is replaced with a fresh stabilizing solution.

  In the HF excavator 1 of the present embodiment configured as described above, the cleaning means 11 is provided at the upper end of the frame 3 of the excavator body 2 and a part of the muddy water 30 sucked up by the suction pump 9 is removed. The slime deposited on the lower wall surface 27c is guided to the injection pipe 12 of the cleaning means 11 and sprayed from the injection holes 13a, 14a of the injection pipe 12 toward the lower wall surface 27c of the node portion 26 of the pile hole 25, so that the pile hole 25 Since the shaft portion 26 of the pile hole 25 is widened by the widening bucket 23 of the ED excavator 22, the node portion 27 is formed in the middle portion of the shaft portion 26, and the ED is formed from the inside of the pile hole 25. After removing the widening bucket 23 of the excavator 22, a slime cleaner is inserted into the pile hole 25, and the slime 28 deposited on the lower wall surface 27c of the node 27 is washed away by the slime cleaner. Is not required.

  Further, after removing the widening bucket 23 of the ED excavation 22 from the pile hole 25, the suction pump of the excavator body 2 of the HF excavator 1 inserted into the pile hole 25 is driven under the node portion 27 of the pile hole 25. The operation of cleaning the slime 28 deposited on the wall surface 27c and the muddy water 30 containing the slime 28 deposited on the bottom of the pile hole 25 are discharged to the ground. The operation of substituting with the liquid can be performed.

  Accordingly, the number of steps as a whole can be reduced, and the lower wall surface 27c of the node 27 of the pile hole 25 is washed, and the slime 28 deposited on the lower wall surface 27c is washed away in the pile hole 25, The time required to discharge the muddy water 30 including the accumulated slime 28 to the ground can be shortened, thereby reducing the time required for constructing the pile hole 25 and shortening the construction period as a whole. .

  Moreover, since the injection pipe 12 of the cleaning means 11 is fixed to the upper end of the rigid frame 3, the injection pipe 12 is not shaken by the pressure of the muddy water injected from the injection holes 13a and 14a of the injection pipe 12. The muddy water 30 injected from the injection holes 13a and 14a can be reliably applied to the lower wall surface 27c of the node 27, and the slime 28 deposited on the lower wall surface 27c can be reliably washed out into the pile hole 25.

  The injection holes 13a and 14a of the injection pipe 12 are set to an injection angle corresponding to the inclination angle of the lower wall surface 27c of the node 27, and the muddy water 30 injected from the injection holes 13a and 14a is orthogonal to the lower wall surface 27c. Since it is comprised so that it may hit from the direction, the slime 28 deposited on the lower wall surface 27c can be reliably washed off by the muddy water 30.

  Therefore, the slime 28 does not remain on the lower wall surface 27c of the node 27, and the quality of the wall-like underground structure with a node constructed in the pile hole 25 can be improved.

  Further, since the slime cleaner is not necessary, the number of facilities to be used can be reduced, and the equipment cost can be reduced.

  In addition, since the number of facilities to be used can be reduced, a place for installing the facilities can be reduced, and the range of applicable sites can be expanded.

In the above description, the present invention is applied to the HF excavator 1 for constructing a rectangular cross-sectional pile hole 25 for a wall-like underground structure with a node, but a TBH excavator for constructing a circular cross-sectional pile hole. The present invention may be applied to the TBH excavator in combination with the above-described cleaning means 11 to clean and remove the slime deposited on the node of the pile hole having a circular cross section.
Further, the configuration of the injection pipe is not limited to the above, and a part of the muddy water 30 is supplied from the suction pipe 10 to a pipe provided along both sides in the longitudinal direction of the frame (the pieces on the side where the nodes are formed). It is sufficient if it is configured so as to be injected.

1 Excavator (HF excavator)
2 Excavator Main Body 3 Frame 3a Front 3b Rear 3c 3d Side 4 Head 5 Sheave 6 Wire 7 Cutter Drum 9 Suction Pump 9a Discharge Port
DESCRIPTION OF SYMBOLS 10 Suction pipe 11 Cleaning means 12 Injection pipe 13 1st pipe part 13a Injection hole 14 2nd pipe part 14a Injection hole 15 3rd pipe part 16 4th pipe part 17 5th pipe part 18 6th pipe part 19 7th pipe part DESCRIPTION OF SYMBOLS 20 Branch pipe 21 Open / close valve 22 ED excavator 23 Widening bucket 25 Pile hole 26 Shaft part 26a Wall surface 27 Node part 27a Upper wall surface 27b Middle wall surface 27c Lower wall surface 28 Slime 30 Mud water 31 Slime cleaner 32 Suction port 33 Discharge port

Claims (5)

An excavator used for a reverse circulation excavation method in which a pile hole is constructed by sucking up excavated earth and sand together with mud and discharging it to the ground while excavating the ground,
It has an excavator body equipped with a suction pump and a suction pipe that sucks up excavated soil with mud and discharges it to the ground,
An excavator characterized in that a part of the excavator body is provided with cleaning means that branches off from the suction pipe and injects a part of the muddy water sucked up by the suction pump to the side.   The excavator main body is provided with a rectangular columnar frame, a cutter drum rotatably provided at a lower end of the frame, the suction pump provided at a lower end portion of the frame, the inner side of the frame, and the suction 2. The excavator according to claim 1, further comprising: the suction pipe that connects the pump and the ground, and the cleaning means is provided at an upper end of the frame or a portion below the upper end.   The cleaning means is fixed to the frame, and has a rectangular annular injection pipe provided with a plurality of injection holes in a portion facing the wall surface of the nodal part of the pile hole, and between the injection pipe and the suction pipe. The excavator according to claim 2, further comprising: a branch pipe that connects the pipe and an open / close valve that opens and closes between the branch pipe and the suction pipe. While excavating the ground with a hydrophrase excavator, the suction pump is driven while supplying a stable liquid from the ground, and the excavated earth and sand is discharged to the ground through the suction pipe together with the muddy water, so that the shaft part of the pile hole with a rectangular cross section is removed. Forming, and
By removing the hydrophrase excavator from within the pile hole, inserting an earth drill excavator into the pile hole, and driving the earth drill excavator, a node portion is provided at an intermediate portion of the shaft portion of the pile hole. Forming a step;
The earth drill excavator is removed from the pile hole, the hydrophrase excavator is inserted into the pile hole, and the suction pump is driven to suck up muddy water from the borehole through the suction pipe, Supplying a part of the muddy water to the cleaning means branched from the suction pipe, and spraying the cleaning means toward the wall surface of the node portion to wash off slime deposited on the wall surface;
Slime accumulated at the bottom of the pile hole by stopping the supply of muddy water to the cleaning means and supplying the stable liquid from the ground into the pile hole and repeatedly discharging the excavated earth and sand together with the muddy water. The excavation method is characterized by comprising a step of discharging muddy water containing lime to the ground and replacing the muddy water containing slime in the pile hole with a good quality stabilizing liquid. A cleaning method used in a reverse circulation excavation method of constructing a pile hole having a node by sucking up excavated soil together with mud and discharging it to the ground while excavating the ground,
A part of the muddy water sucked up from the inside of the pile hole by the suction pump provided in the excavator main body of the excavator for excavating the ground is jetted toward the wall surface of the node portion, so that the slime deposited on the wall surface is collected. A cleaning method characterized by washing off.

Images