JPH0629499B2 - Gravel pile construction method and its equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention creates a gravel pile (a columnar body of sand, gravel, crushed stone, etc.) in soft ground, and absorbs moisture in the ground through the gravel pile, The present invention relates to a gravel pile construction method for discharging and a device therefor. In particular, the present invention inserts a tubular bag body into the casing while piercing the casing into the ground, fills the tubular bag body with gravel to form a bagging gravel pile, and the bagging gravel pile is provided. The present invention relates to a method and a device for burying only chisel in the ground.

(Prior Art) As a conventional construction method of this type, there is one disclosed in Japanese Patent Publication No. 58-39972. This is attached to the outer periphery of the sand introduction pipe that is hung continuously at the lower part of the sand hopper, and attached with a water-permeable tubular bag that is contracted and held in a bellows shape so that it is gradually pulled out downward along it, and The lower end of this tubular bag is tightly bound, and while the casing is driven into the ground by a vibration driving device, the sand in the sand hopper is inserted into the casing while filling the tubular bag from the sand introduction tube, The casing is pulled out and the sand bag is left in the ground.

(Problems to be Solved by the Invention) According to the above-mentioned conventional method, once the long tubular bag body is once attached to the sand introducing pipe, the subsequent work is easy and the construction of a plurality of sand piles is possible. Although it can be performed continuously, when installing this long tubular bag, remove the machine frame from the sand introduction pipe, or use a tubular bag with a length for multiple sand piles in the sand introduction pipe. The installation work was extremely troublesome because it was necessary to squeeze it up and keep it in a retracted state.

INDUSTRIAL APPLICABILITY The present invention does not require the troublesome mounting work of the tubular bag as described above, and continuously forms a belt-shaped water-permeable sheet on the tubular bag along the forming chute at the bottom of the gravel hopper. It is an object of the present invention to provide a construction method and a device which are fed down while being inserted into a casing.

(Means for Solving the Problem) In order to achieve the above-mentioned object, in the method of the present invention according to claim 1, the rotary casing 3 in which the fixed casing 6 is inserted is rotated and the ground casing W is rotated. During the perforation, while the perforation is being performed, the belt-shaped water-permeable sheet 12 is wound around the cylindrical forming chute 8 that is hung continuously under the gravel hopper 7 and the overlapped edges of the sheet 12 are vertically aligned. The tubular bag body 17 is formed by joining by the direction joining means 16
The lower part 17 of the gravel hopper 7 is inserted into the fixed casing 6 with the lower end closed, and the gravel G such as sand and gravel in the gravel hopper 7 is inserted into the tubular bag body 17 through the tubular forming chute 8. After filling the casings 3 and 6 to a predetermined depth and the lower end of the tubular bag 17 filled with the gravel G reaches the lower end in the fixed casing, the tubular bag 17 is filled. The upper end is cut below the cylindrical forming chute 8 so that both casings 3 and 6 are pulled out.

In the method of the present invention according to claim 2, the rotary casing 3 in which the fixed casing 6 is inserted is rotated, and the rotary casing 3 is hung and connected to the lower portion of the gravel hopper 7 before being inserted into the ground W. While the belt-shaped water-permeable sheet 12 is being wound around the cylindrical forming chute 8 and the both side overlapping edges of the sheet 12 are joined by the vertical joining means 16, a tubular bag body 17 is formed. After the body 17 is fed downward, it is inserted into the fixed casing 6 to close the lower end of the tubular bag body 17, and then the rotary casing 3 is inserted into the ground together with the fixed casing 6.
After the casings 3 and 6 reach a predetermined depth, the gravel G such as sand and gravel in the gravel hopper 7 is filled into the tubular bag 17 in the fixed casing 6 through the tubular forming chute 8. After that, both the casings 3 and 6 are pulled out while the tubular bag body 17 is fed downward, and the tubular bag body 17 is cut below the both casings 3 and 6.

Furthermore, the apparatus for carrying out the gravel pile construction method according to claim 1 is a rotary casing 3 rotatably hung under a machine frame 1 suspended by a leader, and a rotary casing for driving the rotary casing 3. Driving means 5, a fixed casing 6 whose upper end is attached to the machine casing 1 side and is inserted into the rotary casing 3 over its entire length, a gravel hopper 7 arranged in the machine casing 1, and a fixed casing 6. , A cylindrical forming chute 8 which is hung and connected to the lower part of the gravel hopper 7, and a sheet supplying means 15 which supplies a strip-shaped water-permeable sheet 12 to the vicinity of the upper end of the cylindrical forming chute 8. Forming plate 14 for winding the water-permeable sheet 12 around the entire outer peripheral surface of the cylindrical forming chute 8 and overlapping both side edges of the sheet 12, and the sheet 12 wound on the cylindrical forming chute 8. Longitudinal joining means 16 that joins both side overlapping portions to form a tubular bag body, and a tubular bag body 17 that is fed downward to insert the tubular bag body 17 into the fixed casing 6. It is provided with means 18 and a bag body cutting means for cutting the upper end portion of the tubular bag body 17 filled with the gravel G below the tubular forming chute 8.

(Example) An example will be described with reference to the drawings.

FIG. 1 shows a dual gravel pile construction device for carrying out the invention (construction method) according to claim 1. In addition, this gravel pile forming apparatus can also implement the invention (construction method) according to claim 2, and in this case, the use of the heat welding cutting apparatus 20 described later is unnecessary.

In FIG. 1, reference numeral 1 is a machine frame that is suspended and supported by a leader (not shown) installed upright on a crawler crane,
A pair of left and right rotary casings 3, 3 each having a screw 2 screwed on the outer peripheral surface over the entire length are rotatably hung at the lower part of the machine casing 1, and the lower ends of the rotary casings 3 are respectively installed. A shoe (bottom lid) 4 is attached so as to be openable and closable.

The rotary casings 3 and 3 are driven by rotary drive mechanisms 5 and 5 (see FIG. 3) provided in the machine frame 1 to rotate in opposite directions.
A fixed casing 6 having a diameter slightly smaller than that of the rotary casing 3 is inserted and arranged along the entire length of the rotary casing 3, and an upper end portion of the fixed casing 6 is fixed to the machine casing 1.

7 is a gravel hopper arranged on the upper part of the machine frame 1,
At the bottom of the gravel hopper 7, a fixed casing 6,
Cylindrical forming chutes 8 and 8 are provided at positions directly above, respectively.
Are vertically integrated downwards. Further, inside the gravel hopper 7, an on-off valve 10 for opening and closing the discharge port 9 to each forming chute 8 is provided, and each on-off valve 10 is an air cylinder.
Driven by 11.

Reference numeral 12 is a strip-shaped mesh (net-shaped) sheet made of a thermoplastic such as vinyl chloride as a strip-shaped water-permeable sheet wound in a roll shape on a reel 13 which is detachably attached to the machine frame 1. As shown in FIG. 2, the roll-wound mesh sheet 12 is supplied to the vicinity of the upper end of each forming chute 8 by the sheet supplying means and guided to the forming plate 14, and the forming plate 14 forms the forming chute 8. While being wound on the outer peripheral surface of the mesh sheet 12, both side edges 12a, 12a in the longitudinal direction of the mesh sheet 12 are formed on the outer peripheral surface of the forming chute 8 while being overlapped with each other to form a cylindrical shape. The sheet feeding means includes, for example, a rotation driving mechanism (not shown) for rotating the winding drum portion of the winding frame 13, an intermediate guide roller 15, and the like.

Reference numeral 16 denotes a longitudinal heat sealer as a longitudinal joining means for joining the polymerized longitudinal side edges 12a, 12a of the mesh sheet 12 wound around each forming chute 8 and is shown in FIGS. 1 and 2. As shown in FIG.
The cylindrical bag 17 is formed by heat welding the 12a. Reference numeral 18 denotes a feed roller as a feeding means for feeding the tubular bag body 17 formed by each forming chute 8 downward.
As is apparent from the figure, a pair of cylindrical bags 17 are formed at a position opposite to each other on the lower side of the forming chute 8 and are clamped while holding both sides of the cylindrical bag 17, and the bag 17 is fed downward and fixed. It is designed to be inserted into the casing 6. Reference numeral 19 is a motor that drives each feed roller 17.

Reference numeral 20 denotes a heat-welding cutting device that simultaneously heat-welds and cuts the tubular bag body 17 laterally below the forming chute 8 and has a pair of left and right movable frames 20a, 20a, and one movable frame 20b. The horizontal heat sealer 21b and the cutter 22b are provided with the welding table 21a and the cutter receiver 22a on the other movable frame 20a, and the movable frames 20a and 20b move in opposite directions and come into contact with each other to form a tubular bag. The body 17 is heat-sealed in the lateral direction to seal the lower end of the upper bag body 17, and at the same time, the lower part of the sealing portion is cut to open the upper end of the separated lower bag body 17. It will be.

As shown in FIG. 3, each rotary drive mechanism 5 has small gears 24, 24 fixed to the output shafts 23, 23 of a prime mover (not shown) disposed on the front and rear sides of the upper end of the rotary casing 3. The small gears 24, 24 are meshed with a large gear 25 fixed to the upper end of the rotary casing 3.

Next, an embodiment for carrying out the invention according to claim 1 will be specifically described by using the gravel pile forming device having the above-described configuration.

First, the left and right reels 13 around which the mesh sheet 12 is rolled,
13 are mounted on the machine frame 1 at fixed positions, and
The leading end portion of the mesh sheet 12 slightly fed from 13 is supplied from the guide roller 15 to the forming plate 14, further fitted onto the forming chute 8 via the forming plate 14, and sandwiched by the feed rollers 18, 18. deep. Then, the rotary drive mechanisms 5 and 5 penetrate the ground W while rotating the rotary casings 3 and 3 in the direction of the arrow in FIG. 4A.

On the other hand, each longitudinal heat sealer 16 is moved toward the forming chute 8 to weld both overlapping edge portions of the mesh sheet 12 by the length of the heat sealer 16 to form a tubular bag body 17, and then the heat sealer. 16 is retracted to its original position, and the tubular bag body 17 is moved by a length substantially corresponding to the length of the tubular tube body 17 formed by the welding and joining thereof.
Send by 8 and 18. After that, the heat sealer 16 is again moved closer to the forming chute 8 to weld and join the overlapping edge portions on both sides of the reticulated sheet 12. By repeating such an operation, a series of cylindrical bag bodies 17 are formed almost continuously and are inserted into the fixed casing 6 (see FIG. 4A).

In the case of the tubular bag body 17 formed first, the tip of the tubular bag body 17 is sealed by using the heat welding cutting device 20, and the tubular bag body 17 is inserted into the fixed casing 6. In order to perform the operation easily and surely, after sealing the tip of the tubular bag body 17, the on-off valve 10 is opened and a small amount of the gravel G in the hopper 7 is put into the tubular bag body 17 as shown in FIG. 4A. And weight it.

When the rotary casing 3 reaches a predetermined depth in the ground W and the lower end of the tubular bag 17 reaches the lower end of the fixed casing 6, as shown in FIG. 10, 10
The gravel G in the gravel hopper 7 by opening the
Is filled into the cylindrical bag body 17 through the molding chutes 8 and 8.
When the gravel G is full, the on-off valves 10 and 10 are closed.

After the filling of the gravel G into the tubular bag body 17 is completed, the heat welding cutting device 20 is operated to weld and cut the upper end portion of the tubular bag body 17 below the forming chute 8 to thereby form At the same time as sealing the lower end of the tubular bag body 17 portion on the chute 8 side, the tubular bag body 17 portion on the fixed casing 6 side is separated from the tubular bag body 17 portion on the forming chute 8 side. Then the 4th
As shown in FIG. C, while rotating the rotating casings 3 and 3 in the direction opposite to that at the time of insertion, they are pulled out together with the fixed casings 6 and 6 from the ground W, and only the bag body 17 filled with the gravel G is removed. A gravel pile is formed by leaving it in the ground W (see FIGS. 4C and 4D).

After completing the construction of the gravel pile in one place,
The entire apparatus may be moved to the next predetermined place, and a series of steps similar to the above may be performed. It is possible to form the tubular bag body 17 for ten gravel piles with one strip-shaped mesh sheet 121 that is wound around one reel 13. When this roll-wound mesh sheet 12 is used up, the old winding frame 13 is removed, a new winding frame 13 with the mesh sheet 12 wound in a roll is attached, and the leading end is guided by the guide roller 15 and forming. It suffices to wind it around the plate 14 and the molding chute 8, and these operations can be easily performed.

The above is the description of the embodiment of the invention according to claim 1, in which the rotary casing 3 is inserted into the ground W, and the tubular bag body 17 is formed in the fixed casing 6 while the rotary casing 3 is being inserted. After being inserted, the lower end of the tubular bag 17 reaches the lower end in the fixed casing 6 and both casings 3, 6 reach a predetermined depth in the ground, and then the gravel G on the tubular bag 17 is inserted. Do the filling,
After that, the upper end of the tubular bag body 17 is cut below the tubular forming chute 8, but in the embodiment of the invention according to claim 2, when the rotary casing 3 is inserted into the ground W, First, the tubular bag 17 is formed and inserted into the lower end of the fixed casing 6 to close the lower end of the tubular bag 17, and then the rotary casing 3 is inserted into the ground W. Thereafter, the tubular bag body 17 is filled with the gravel G, both casings 3 and 6 are pulled out, and the upper end portion of the tubular bag body 17 is cut below the both casings 3 and 6. Hereinafter, claim 2
An embodiment of the present invention will be described with reference to FIG.

That is, before the rotary casing 3 is penetrated into the ground W, the mesh sheet 12 is supplied to the forming chute 8 through the forming plate 14, and the mesh sheet 12 is held by the feed rollers 18 and 18, and Move the longitudinal heat sealer 16 toward the forming chute 8 to move the mesh sheet 12
Both sides of the overlapped edges are weld-bonded by the length of the heat sealer 16 to form a tubular bag body 17, and then the heat sealer 16 is retracted to its original position, and the tubular bag body formed by the welding joint. The cylindrical bag body 17 is fed downward by the feed rollers 18 and 18 by a length substantially corresponding to the length of 17. After that, the heat sealer 16 is again moved closer to the forming chute 8 to weld and join the overlapping edge portions on both sides of the reticulated sheet 12. By repeating such an operation, a series of cylindrical bags 17
The tubular bag 17 is inserted into the fixed casing 6 up to the lower end while forming.

Then, when the lower end portion of the tubular bag body 17 reaches the lower end portion in the fixed casing 6, the tubular bag body 17 formed by the feed rollers 18, 18.
Then, the lower feeding is temporarily stopped, and the lower end portion of the tubular bag body 17 is manually bound with a string or the like to close it.

In this way, from the state where the lower end of the tubular bag 17 inserted into the fixed casing 6 is closed, the rotary casing 3 is rotated and penetrated into the ground W together with the fixed casing 6.

When both casings 3 and 6 reach a predetermined depth in the ground W, the opening / closing valves 10 and 10 are opened to fill the gravel G in the gravel hopper 7 into the tubular bag body 17. When the gravel G is full, the on-off valves 10 and 10 are closed.

After the filling of the gravel G into the tubular bag 17 is completed as described above, the casings 3 and 6 are pulled out to remove the gravel G.
The tubular bag body 17 filled with the gravel G is left in the ground W. In this case, the tubular bag body 17 portion filled with the gravel G is fitted into the forming chute 8 to feed the roller 18, Since it is connected to the bag body 17 part sandwiched by 18, if both casings 3 and 6 are pulled out in this state, the tubular bag body 17 part filled with gravel G will be
6 will be pulled up to the ground together with 6, or will be separated from the bag body 17 portion on the molding chute 8 side.

Therefore, in order to avoid such rising and division of the tubular bag body 17 and leave only the tubular bag body 17 portion filled with the gravel G in the ground W and prepare for the next construction work, The operation of forming the tubular bag body 17 from the mesh sheet 12 is restarted, and the tubular bag body 17 formed by the forming chute 8 is fed into the casings 3, 6 by the feed rollers 18, 18.
The rotary casing 3 is pulled out together with the fixed casing 6 while feeding downward at a speed substantially the same as the pulling speed.

When both casings 3 and 6 are pulled up to the ground in this way, the lowering of the tubular bag body 17 is stopped, and the upper end portion of the tubular bag body 17 portion filled with this gravel is attached to both casings 3 and 6. Cut with a knife or the like below. Since the lower ends of the casings 3 and 6 are located at a lower position on the ground, the cutting work in this case can be easily performed by the worker on the ground. By cutting the tubular bag body 17, the tubular bag body 17 portion extending from the forming chute 8 and inserted to the lower end in the fixed casing 6, and the tubular bag body filled with the gravel G and left in the ground W. It will be separated into 17 parts of the body. Then, the lower end portion of the cylindrical bag body 17 portion inserted into the fixed casing 6 is tightly bound and closed with a string or the like to prepare for the next construction work.

In the embodiment of the invention according to claim 1 described above, the upper end of the tubular bag body 17 filled with the gravel is automatically cut by the cutter of the heat welding cutting device 20 for cutting below the forming chute 8. However, the lower end of the tubular bag body 17 on the side of the forming chute 8 after cutting may be bound by a worker with a string or the like without using a heat sealer. You may do it.

Further, in the gravel pile forming apparatus of the above-described embodiment, the fixed casing 6 is arranged so as to be immovable with respect to the rotary casing 3, and the lower end of the fixed casing 6 is housed in the lower end portion of the rotary casing 3. However, preferably, as illustrated in FIGS. 5 and 6, the fixed casing 6 is provided to be movable up and down with respect to the rotary casing 3 so that the lower end portion of the fixed casing 6 can protrude from the lower end of the rotary casing 3 when necessary. It is desirable to do so.

That is, as shown in FIGS. 5 and 6, the machine casing 1 is erected and supported around the upper end portion of the fixed casing 6 which is inserted into the rotary casing 3 so as to be relatively rotatable and vertically movable. Plural fluid pressure cylinders 26 are provided, and the piston rods 26a of each fluid pressure cylinder 26 are connected to the fixed casing 6. Therefore, as shown in FIG. 5, the piston rods 26a of each fluid pressure cylinder 26 are normally extended. So that the lower end of the fixed casing 6 fits within the lower end of the rotary casing 3 and the rotary casing 3 is reversed while the gravel pile is being constructed, and the gravel pile that has been bagged up is ground from the lower end of the fixed casing 6 to the ground W. When the fluid is discharged into the inside, the piston rod 26a of each fluid pressure cylinder 26 is contracted as shown in FIG. The required length is projected from the end. When the lower end of the fixed casing 6 projects from the lower end of the rotary casing 3, the shoe 4 is forcibly opened, as is apparent from FIG.

As described above, if the lower end of the fixed casing 6 is projected when the casing is pulled out, even if the shoe 4 is pressed by the earth and sand around the lower end of the rotating casing 3 to close it, the lower end of the rotating casing 3 is closed. The shoe 4 can be maintained in an open state by the fixed casing 6 projecting from it, and the bag 17 discharged from the lower end of the fixed casing 3 does not come into contact with the rotating shoe 4. There is no danger of being damaged by. An air spring device or a rack and pinion drive device may be used instead of the fluid pressure cylinder.

Although the mesh sheet 12 is used as the water permeable sheet in the above-described embodiments of the inventions according to claims 1 and 2, a cloth sheet other than the mesh sheet 12 may be used as long as it has water permeability. Good.

Further, in the embodiment of the invention according to claim 1, the heat sealer 16 is used to join the polymerized side edges of the strip-shaped mesh sheet 12 formed on the forming chute 8 by heat welding. However, in addition to such a heat sealer, a joining means such as a sewing machine that can automatically sew both side edges of the mesh sheet 12 on the outer peripheral side surface of the forming chute 8 can be used. According to such a joining means, the water-permeable sheet can be made of any material other than thermoplastic products.

Furthermore, in the above-described embodiment of the invention according to claim 1, the gravel G is filled into the bag body 17 at the stage when the tubular bag body 17 is almost inserted into the fixed casing 6. If it is possible to securely join both side edges of the mesh sheet 12 on the forming chute 8, while the tubular bag body 17 is being inserted into the fixed casing 6, the gravel G on the tubular bag body 17 can be removed. Filling may be performed.

Further, in each of the above-mentioned embodiments, the description has been given of the double-type gravel pile forming apparatus capable of simultaneously forming two gravel piles, but the present invention can be applied to a single-type or triple-type or more. Is. However, the double type is the most efficient and can be economically constructed.

Furthermore, in the above-described embodiment of the invention according to claim 1, the rolled reticulated sheet 12 is mounted on the machine frame 1, but may be installed on the ground.

(Effect of the Invention) According to the invention of claim 1, while the rotary casing is being pierced into the ground together with the fixed casing, during the piercing,
A tubular water-permeable sheet, a forming chute and a longitudinal joining means are continuously formed into a tubular bag body, and the bag body is inserted into a fixed casing while being fed downward with its lower end closed, After filling the gravel into the tubular bag inside the hopper, both casings reach a predetermined depth, and the lower end of the tubular bag filled with gravel reaches the lower end in the fixed casing. Since the upper end of the bag is cut below the tubular forming chute and both casings are pulled out, the strip-shaped water-permeable sheet is rolled in advance and the forming chute is fed out from the rolled sheet. By supplying the bagging gravel pile to the bag, it is possible to easily form a bagging gravel pile having a desired length and efficiently construct a large number of bagging gravel piles. In particular, when the water permeable sheet is used up, there is no need to perform the troublesome work of removing the sand introduction tube and holding the new bag in a contracted state as in the conventional method, but just using the new water permeable sheet. Since it is only necessary to introduce the tip part of the above into the forming chute side, the work is much simpler than the conventional method, and it is possible to achieve a marked improvement in the construction work efficiency of the gravel pile. According to the invention, before piercing the casing into the ground, a tubular bag is formed from a water-permeable sheet, and the tubular bag is inserted into the fixed casing while being fed downward, After closing the lower end of the bag body, the rotary casing was pierced into the ground together with the fixed casing, and after both casings reached a predetermined depth, the gravel was put into the tubular bag body through the tubular forming chute. Cylindrical bag filled after filling While lowering the body, pull out both casings and cut the tubular bag body under both casings, so the first bagging gravel pile was buried in the ground and the pile construction work at that location was completed. After that, when both casings are pulled up to the ground, the tubular bag is already inserted in the fixed casing, so that it is possible to immediately move on to the next gravel pile construction work, further improving work efficiency. You can

According to the gravel pile forming apparatus of the third aspect, all the gravel pile forming work can be automatically performed, which can greatly contribute to labor saving of work and improvement of work efficiency.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of a gravel pile forming apparatus showing an embodiment of the present invention, FIG. 2 is a partially enlarged perspective view of the apparatus of FIG. 1, and FIG.
FIG. 3 is a sectional view taken along the line III-III in FIG. 1, FIGS. 4A to 4D are explanatory views showing a construction process of the present invention, and FIGS. 5 and 6 show a gravel pile forming apparatus according to another embodiment, respectively. FIG. 1 ... Machine frame, 2 ... Screw, 3 ... Rotating casing, 4 ... Shoe, 5 ... Rotation drive mechanism, 6 ... Fixed casing, 7 ... Gravel hopper, 8 ... Forming chute, 10 ... Open / close valve, 12 ... Mesh sheet (band-shaped water permeable sheet), 12a ... Vertical edge of mesh sheet, 14 ... Forming plate, 16 ... Vertical heat sealer (longitudinal joining means), 17 ... Tube Bag, 18 ... Feeding roller (feeding means), 20 ...

Claims (3)

[Claims] 1. A rotary casing having a fixed casing inserted therein is rotated while being pierced into the ground, and during the piercing, a strip-shaped chute is formed on a cylindrical molding chute that is hung continuously under the gravel hopper. While the water-permeable sheet is being wound and supplied, both side overlapping edges of the sheet are joined by a longitudinal joining means to form a tubular bag body, and the tubular bag body is fed downward with its lower end closed. While inserting into the fixed casing, gravel such as sand and gravel in the gravel hopper is filled into the tubular bag inside the fixed casing through the tubular forming chute, and both casings reach a predetermined depth. After the lower end of the tubular bag filled with gravel reaches the lower end of the fixed casing, the upper end of the tubular bag is cut below the tubular forming chute and both casings are pulled out. Gravel pile construction method. 2. A belt-shaped water-permeable sheet is wound around a cylindrical forming chute which is hung continuously under the gravel hopper, before being inserted into the ground while rotating a rotating casing having a fixed casing inserted therein. While feeding the sheet, both side overlapping edges of the sheet are joined by a longitudinal joining means to form a tubular bag body, and while the tubular bag body is fed downward, the tubular bag body is inserted to its lower end portion, After closing the lower end of the tubular bag, the rotary casing was pierced into the ground together with the fixed casing, and after both casings reached a predetermined depth, gravel such as sand and gravel in the gravel hopper was removed. Filling the tubular bag inside the fixed casing through the tubular forming chute, then pulling out both casings while lowering the tubular bag, and cutting the tubular bag below both casings. Characteristic gravel pile construction Method. 3. A rotating casing, which is rotatably suspended from a lower portion of a machine frame suspended by a reader, a rotation driving means for driving the rotating casing, and an upper end portion attached to the machine frame side for rotation. A fixed casing inserted over the entire length in the casing, a gravel hopper arranged in the machine frame, a cylindrical formed chute continuously connected to the lower portion of the gravel hopper located immediately above the fixed casing, and a belt-like shape. Sheet feeding means for feeding the water-permeable sheet to the vicinity of the upper end of the tubular forming chute, and forming for winding the supplied water-permeable sheet around the entire outer surface of the tubular forming chute and superposing both side edges of the sheet. The plate and the longitudinal joining means for joining both side edge overlapping portions of the sheet wound around the tubular forming chute to form a tubular bag body, and the tubular bag body in the fixed casing. A feed means for feeding the tubular bag downward for insertion, and a bag cutting means for cutting the upper end of the tubular bag filled with gravel below the tubular forming chute. An apparatus for carrying out the gravel pile construction method according to claim 1.