JP2615096B2 - Drilling method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the invention]

<Industrial application field> The present invention relates to a method of constructing a cast-in-place pile and excavating a hole for laying a steel pipe pile, a concrete pile, a steel pipe sheet pile, and the like. <Conventional technology> In excavation, excavated soil must be discharged. Conventionally, excavated soil is excavated by using a screw conveyor provided on a shaft equipped with an auger head, In some cases, this is sucked up by vacuum. <Problems to be solved by the invention> However, when the depth of the excavation hole is as deep as 50 to 60m, the former one does not discharge the excavated sediment sufficiently, and the excavated sediment resists the settlement of the pile. Becomes large. Even in the latter case, when the depth becomes deeper, the discharge of excavated sediment will not be sufficient, and since the excavated sediment will be discharged through the hollow shaft, the sediment at the center of the hole will be The discharge of sediment in the periphery is not sufficient. The present invention has been made to solve such a problem.

Configuration of the Invention

<Means for Solving the Problems> According to the present invention, a water pipe and an air pipe are provided on a shaft that is rotatably driven with an auger head mounted on a lower end, and the upper end is connected by a connecting plate fixed around the shaft. The drain pipe, which has become a straight pipe, is attached to the outside of the shaft to supply the liquid for mudification of excavated earth and sand from the water pipe. Air is supplied through the pipe, and by the lifting effect of the air, the excavated soil is excavated from the bent upper end of the discharge pipe which is supported by the connecting plate fixed to the periphery of the shaft and rotates around the shaft through the annular saucer. It has the characteristic of discharging. <Operation> According to the present invention, mudified excavated earth and sand is discharged through a discharge pipe by a lifting effect of air supplied to a discharge pipe attached to a shaft. Because it rotates around the shaft,
Excavated earth and sand around the hole can be reliably discharged, and the mud collection area can be increased.Furthermore, the bent discharge pipe rotating around the shaft supported by the connecting plate fixed around the shaft can be bent. Since the excavated earth and sand is discharged from the upper end through an annular pan, the exhaust pipe is located outside the shaft as described above to widen the mud collection area, but with a simple configuration, the soil was collected over a wide area. The mud can be discharged smoothly, and the discharge pipe is straight tubular except for the upper end, so that the mud does not clog in the straight tubular part, and the possibility of mud clogging in the discharge pipe is slightly reduced. Even if there is, it will be clogged at the bent portion at the upper end, and since this portion is on the ground, the clogged portion can be easily removed. <Exemplary Embodiment> The present invention will be described based on the illustrated apparatus. In the illustrated drilling apparatus, a tubular shaft 3 is attached to an auger drive unit 1 via a swivel apparatus 2 and a shaft 3
An auger head 4 having an excavating stirrer blade 40 is attached to the tip of the aerial, and an air pipe 5 and a discharge pipe 6 are further provided in parallel with the shaft 3. The shaft 3, which is driven to rotate by the auger drive unit 1 and has an auger head 4 attached to the tip, serves as a passage for sending water for muddy excavated earth and sand toward the tip of the shaft 3. The water sent through the inside of the shaft 3 is discharged as a jet from a tip end surface of the shaft 3 and a jet port provided in the auger head 4. As shown in FIG. 2, the swivel device 2 includes an outer cylinder 20 and an inner cylinder.
Auger drive unit 1 and shaft 3
And a jacket 21 rotatably attached to the outer surface of the outer cylinder 20 via an O-ring 23. The jacket 21 is suspended from the auger drive unit 1 by the support arm 18. Have been. The space between the inner peripheral surface of the jacket 21 and the outer peripheral surface of the outer cylinder 20 communicates with the space between the outer cylinder 20 and the inner cylinder 22 in the double pipe, and the upper end of the air pipe 5 It is connected. As shown in FIG. 3, the air pipe 5 and the discharge pipe 6 are supported at a plurality of upper and lower locations by a connecting plate 30 fixed to the shaft 3, and rotate together with the shaft 3.
The lower end of the discharge pipe 6 opens downward in the vicinity of the auger head 4, and the lower end of the air pipe 5 is connected slightly above the lower end opening as shown in FIG. The upper end of the air pipe 5 is connected to the swivel device 2 as described above, and the upper end of the discharge pipe 6 is bent in a U-shape, and is suspended from the auger drive unit 1 via the support arm 19. It opens downward above the receiving tray 60. A conduit 61 and a mud collecting pipe 62 are connected to the receiving tray 60 as a mud collecting device. In the figure, reference numeral 64 denotes a hoisting device for adjusting the length of the mud collecting pipe 62, and 63 denotes a tank. In the excavation by the excavation device, the auger drive unit 1 drives the shaft 3 and the auger head 4 to perform excavation, and discharges water through the shaft 3 to convert excavated soil into muddy water. Then, the supply of air to the air pipe 5 is started from the time when the excavation is performed for several meters. The air sent to the air pipe 5 rises through the inside of the discharge pipe 6, and at this time, the muddy water is involved and the muddy water is raised by its lifting effect. Further, since the discharge pipe 6 rotates around the shaft 3, the muddy water is surely discharged to the entire area of the hole. The mud that has risen inside the discharge pipe 6
From the tank 63 through a conduit 61 and a mud collecting pipe 62, where water is separated. At the time of this excavation, as shown in FIG. 5, if the steel pipe casing 7 is used together, the vertical accuracy of the excavation can be increased. At this time, the steel pipe casing 7 may be hung from the auger drive unit 1. However, as shown by a chain line in FIG. Vertical accuracy can be further increased. Further, as shown in FIGS. 7 and 8, the engagement arm 48 is slidably engaged with the junction 46 of the already installed steel pipe sheet pile 45 in the vertical direction, and the outer periphery of the lower part of the steel pipe casing 7 is loosened. If the rotatable support 47 is attached to the engagement arm 48, the vertical accuracy can be further increased. In this manner, the excavation is performed while discharging the excavated earth and sand. After the excavation to the required depth is completed, the auger head 4 is taken out of the excavation hole, and the steel pipe pile, the concrete pile, or the steel pipe is removed. A sheet pile or the like is hung and inserted into the excavation hole, and the periphery of the pile and the tip of the pile are reinforced with mortar or the like and reinforced. When cast-in-place piles are used, Fig. 6 (a)
As shown in (b), a reinforcing steel cage 93 is suspended in the excavation hole, and concrete 95 is filled and poured through the tremy tube 94. Further, when the steel pipe casing 7 is used for the excavation as described above, the steel pipe casing 7 can be used as a pile or a sheet pile by leaving the steel pipe casing 7 in the hole and solidifying it. Although the shaft 3 also serves as the water tube 8,
One in which three pipes of an air pipe 5, a discharge pipe 6, and a water pipe 8 are provided side by side in the shaft 3, one in which the shaft 3 also serves as the air pipe 5, or one in which the inside of the cylindrical shaft 3 is divided into two, and the water pipe 8 and the air The same drilling operation can be performed even when the shaft 5 is used also for the pipe 5.

【The invention's effect】

As described above, in the present invention, the auger head is attached to the lower end, and the water pipe and the air pipe are provided side by side on the shaft that is driven to rotate, and the connecting pipe fixed around the shaft excluding the upper end forms a straight tube. The drain pipe is attached to the outside of the shaft to supply muddy liquid for excavated earth and sand from the water pipe, and to supply air through the air pipe to the lower part of the drain pipe that has an open lower end and an upper end connected to the mud collector. Then, by the lifting effect of the air, the excavated earth and sand is discharged from the bent upper end of the discharge pipe rotating around the shaft supported by the connecting plate fixed to the periphery of the shaft through the annular saucer. The muddy excavated soil is discharged through the discharge pipe by the lifting effect of the air supplied to the discharge pipe attached to the Even if it is deep, it can surely discharge excavated earth and sand, and since the discharge pipe rotates around the shaft driven and rotated with the auger head attached to the lower end, the entire area of the hole In particular, the excavated earth and sand can be reliably discharged from the bent upper end of the discharge pipe that rotates around the shaft supported by the connecting plate fixed to the periphery of the shaft. Although the discharge pipe is positioned outside the shaft as described above to widen the mud collection area, the simple configuration allows for smooth discharge of the polluted mud over a wide area. Since the discharge pipe has a straight tubular shape except for the upper end, mud does not clog in the straight tubular portion, and even if there is a possibility that mud may be clogged in the discharge pipe, the upper end may be bent. Will be clogged in parts, this part because it out on the ground, in which it is possible to easily remove the jammed portion.

[Brief description of the drawings]

1 is a cross-sectional view of an apparatus according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of a swivel apparatus of the above, FIG. 3 is a horizontal cross-sectional view of the above, and FIG. 5, FIG. 5 is a cross-sectional view in the case of using a steel pipe casing together, FIGS. 6 (a) and 6 (b) are cross-sectional views showing a process of forming a cast-in-place pile, and FIGS. It is a partial front view and a horizontal cross-sectional view showing an example, wherein 3 is a shaft, 4 is an auger head, 5 is an air pipe, and 6 is a discharge pipe.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Koji Sumi 2--20 Koraibashi, Higashi-ku, Osaka-shi, Osaka Inside the Takechi Corporation (72) Inventor Takahiro Kitamura 2--20 Koraibashi, Higashi-ku, Osaka-shi, Osaka Takechi Corporation In-house (72) Inventor Shingo Yamamoto 2-20 Koraibashi, Higashi-ku, Osaka-shi, Osaka Prefecture Takechi Corporation (56) References JP-A-57-155432 (JP, A) JP-A-60-192022 (JP, A) 62-172793 (JP, U)

Claims (1)

(57) [Claims] A water pipe and an air pipe are attached to a shaft which is rotatably driven with an auger head mounted on a lower end thereof, and a discharge pipe which is formed in a straight tubular shape except for an upper end portion by a connecting plate fixed around the shaft. Is attached to the outside of the shaft to supply the liquid for mudification of excavated earth and sand from a water pipe, and supply air through an air pipe to a lower part of a discharge pipe having an open lower end and an upper end connected to a mud collector. A borehole for discharging excavated earth and sand from a bent upper end of a discharge pipe rotating around the shaft supported by a connecting plate fixed to the periphery of the shaft by a lifting effect by air through an annular tray; Method.