JP2001342789A - Accident prevention method and excavation rod during pile bore drilling - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent any accident during cutting-off or coupling of drilling rods. SOLUTION: This method is capable of preventing the rod from engaging with a drill receiving base at the time of rod separation to enable slip rotation and free sliding at the contact surface between the rod and the drill receiving base for preventing any accident during pile hole drilling.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing an accident at the time of excavating a pile hole mainly for preventing an accident at the time of excavating a single rod from a used excavation rod at the end of the excavation. And a drill rod.

[0002]

2. Description of the Related Art Conventionally, a plurality of excavating rods are connected to each other, and after excavation of a pile hole having a predetermined depth is completed, the rods are sequentially separated while being lifted. The excavator pulls up the rod that is connected, pulls up the upper part of the second connected drilling rod slightly above the ground, and sets the lower rod on the cutting cradle to position horizontally. After that, lower the rod slightly, support the flange on the cutting table and position it vertically, cut off the excavating rods above and below, move it to another place while lifting the upper single rod, and move it to the next place as it is Use for drilling a pile hole or temporarily separate the single rod from the excavator. Next, pull up the next excavation rod placed on the cradle by the pile driver, pull it up until the next rod slightly protrudes to the ground, place it on the cradle, and cut off the excavation rods sequentially in the same way, and excavate Complete the separation of the rod.

[0003]

There is no problem if the conventional drilling rod is separated as long as it proceeds as described above, but since the separation is performed with the intervention of an operator, An accident could occur if not performed as scheduled. For example, when the drill cradle is not set horizontally with respect to the excavation rod (the surface of the excavation site is often inclined because it is soft), the support contact portion of the excavation rod is inclined, and the contact pressure is reduced. If the drilling rod is rotated when the drilling rod is uneven or the projection of the drilling rod (for example, a stirrer bar) is hung on a part of the drilling cradle, the drilling cradle moves and hits the worker. There are cases.

[0004] Further, since the cutting cradle is inclined, the cutting cradle may be displaced in the lateral direction due to the rotation of the excavating rod.

[0005]

As described above, when the cradle is moved with the rotation or movement of the digging rod when the digging rod is separated, an unexpected accident may occur. The accident was prevented beforehand by adopting a structure in which the table and the excavating rod always contact with a smooth surface.

[0006] That is, the invention of the method, when the rod is separated,
It is an accident prevention method at the time of excavation of a pile hole characterized by being able to slide and rotate the contact surface with the rod and the cradle so that the rod and the cradle are not locked, To be able to slide and rotate and to be freely slidable is to prevent the rotational force applied to the rod from being transmitted to the cutting stand.

In the invention of the rod, a flange for abutting the cradle is provided at the upper end of the rod, the rod below the flange is formed over a predetermined length, the outer wall is formed in a cylindrical shape, and the projection is formed. It is a pile hole excavating rod characterized in that it does not have any, provided with a disc-shaped upper flange for abutment of a cradle at the upper end of the rod, a predetermined length below the upper flange, a circle A plate-like lower flange is provided, and a rod between the upper flange and the lower flange is formed in a cylindrical shape without any protrusion, and the lower surface of the upper flange and the upper surface of the lower flange are formed smoothly. Pile drilling rod. Further, a reinforcing rib is provided on the upper surface of the upper flange, and a stirring rod and a kneading drum are fixed at a predetermined length to a rod below the lower flange. The predetermined length is 0.5m to 1.5m
It is what it was.

In the above description, the predetermined length below the upper flange is a length in consideration of the vertical movement of the excavating rod after the cutting cradle has been set. Although it is possible, the rod may be further moved up and down depending on the situation at the site (or when the cradle is inclined).

The pile hole excavating rod according to the present invention can be applied to all rods conventionally used for excavating a pile hole, and is not limited to a stirring rod or a kneading drum, but may be a guiding means (a guiding drum or a guiding drum). Tool), a stirring means (a stirring rod, a stirring arm, a protrusion, etc.) or a screw or other means for moving the excavated soil in the axial direction (for example, a rectangular plate having a lead) may be provided in a projecting manner.

In the above invention, the upper surface of the cutting pedestal is
It is necessary to form the sliding surface up to an inclination of 0 to 45 degrees with respect to the center line of the rod.

That is, the ground surface at the site is expected to be softened and muddy, and even if the upper surface of the cradle is set horizontally (at right angles to the center line of the rod), uneven settlement will occur during the work. However, the upper surface of the cutting cradle may be inclined.

The upper flange in the above invention is required to stably hold the rod and smoothly rotate the rod in the cutting support. Therefore, the lower surface of the upper flange must be smooth, but the upper surface is preferably reinforced, and usually has four or more ribs. The lower flange limits upward movement of the drill rod,
It is a requirement that it can slide even when it comes into contact with the lower surface of the cutting stand. Therefore, the upper surface of the lower flange must be smooth. The lower surface of the lower flange need not necessarily be smooth. Therefore, a reinforcing rib may be provided in some cases.
However, in consideration of a case where the worker mistakenly supports the lower flange on the cutting stand, it is preferable that the lower surface of the lower flange has no rib.

In the above invention, both the upper flange and the lower flange are disc-shaped, and the size thereof preferably stops within the outer end of the stirring rod. For example, it is common to reduce the radius by 5% to 20% of the length of the stir bar.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention strictly regulates the relationship between a drilling rod and a cradle so as to prevent an accident from occurring during the work of separating the drilling rod. Even if careless handling is not performed as usual, accidents are prevented from occurring.

In order to stably hold the excavating rod on the cutting cradle, the upper flange is fixed, and when the excavating rod is raised, the stirring rod and the like do not contact the cutting cradle. The lower flange was fixed, and the rod between the upper and lower flanges was formed smoothly.

In the above-mentioned cutting cradle, depending on the state of the ground surface, it may not be possible to maintain the posture at the time of setting.
Even when the rod is inclined from 0 to 45 degrees with respect to the excavation rod, the rod can rotate smoothly and slide smoothly.

Although the above description has been made on the case of detaching the rod having a high risk, the risk is low even when the rod is connected in the opposite manner, and the same effect is obtained when the standard operation procedure is deviated.

[0018]

Embodiment 1 An embodiment of the method of the present invention will be described with reference to FIG.

First, a special head with a drilling blade and a single rod are sequentially connected and mounted on a pile driver as a drilling rod. When a pile hole is drilled to a predetermined depth while rotating the drilling rod, a predetermined cement milk is prepared. Pull out the drilling rod while injecting
Stop with approximately 1m of the upper connecting part of the single rod exposed to the ground.

Next, a cutting pedestal is disposed so as to sandwich the upper shaft portion of the excavating rod, and the rod is stopped in the horizontal direction. Subsequently, the rod is slightly pulled down, and the upper flange of the rod is placed on the cutting cradle to stop the rod in the vertical direction. Then, the uppermost single rod is cut off from the connected rod, and the single rod is pulled further upward with an excavator as it is, and moved to a rod temporary storage area outside the excavation area, or moved to the next pile hole excavation and then directly Use.

Next, the excavating rod mounted on the cutting cradle is mounted on the excavator, and the rod is pulled up while injecting the cement milk. The above-described operation procedure is repeated to sequentially separate the single rod. However, there is a delay in communication between the operator and the operator of the pile driver in the above (temporal), and even if the drilling rod rotates, rises or descends during disconnection, excavation does not take place. If the rod and the cradle are in smooth contact, there is no risk of harm to the operator.

When connecting the rods, the procedure is reversed, and the degree of danger is low, but it goes without saying that the safety is just as effective.

[0023]

Embodiment 2 According to the present invention, 40 cylindrical piles (500φ) can be used.
An embodiment in the case of embedding m will be described with reference to FIGS.

The excavating rod 1 in this excavation work has a rod shaft diameter of 180 φ, a kneading drum 2 (530 φ), and a stirring rod 3
(350φ) and using a special head with a digging blade,
The drilling rod is rotated and excavated while appropriately injecting water from the tip, and the excavated soil that has been agitated, crushed and muddy is kneaded to the inner wall of the shaft of the pile hole 4 to form a strong pile hole wall, and the bottom of the pile hole is formed. And the cement milk is sequentially injected from the bottom of the hole. After mixing the excavated soil and cement milk, making it into soil cement and filling the pile hole almost up to the pile mouth, a predetermined pile is buried.

The pile driver has a special head attached to the tip,
Then, four 10-m single rods are sequentially mounted on the excavator and excavated. After excavating 40 m to form a pile hole of the required size and shape, pull up this drilling rod while injecting cement milk, leave a second single rod from the upper end of this drilling rod, leaving about 1 m in the upper part, and lower flange 6 is stopped in the state (position) where the rod 1 is put in the ground,
To sandwich the excavating rod shaft 1a (between the upper flange and the lower flange width).

Here, the upper flange 5 (16t, 300
φ) is a flat disk, and a rib 5
a is formed, no rib is formed on the lower surface, and the strength is sufficient to withstand the weight of the excavating rod 1 and the load of excavated soil. Therefore, even if the columnar excavating rod is rotated due to a malfunction or an operation error, the shaft of the excavating rod merely rotates and slides with respect to the cutting support 7, and the cutting support 7 does not rotate or move. The contact surface has such a shape.

Next, the excavating rod 1 is lowered, the upper flange 5 is placed on the cutting stand 7, the single rod 10 is separated from the excavating rod 1, and the excavating rod 1 is fixed.

Here, since the distance between the upper flange and the lower flange of the outer diameter of 300φ is set to 60 cm, even if the installation position of the cutting support 7 is shifted up and down by a considerable amount, there is a sliding effect.
There is no danger that the cradle will rotate, move, lift, etc. with the excavating rod, and even if the ground on which the cradle 7 is installed is inclined or loose ground, it will be within the working limit of 45 degrees. The safety can be similarly secured up to the inclination of.

The lower flange 6 has no ribs on the upper and lower surfaces, and has a similar interval width (60 cm to 100 cm) to the stirring bar located below the lower flange 6.
m), the shape of the sliding surface is cylindrical, and there is a danger even if the position of the pedestal 7 is shifted to the lower side of the lower flange 6 due to large ground inclination, loose ground or incorrect installation position adjustment. It is considered that there is no sex.

Subsequently, the upper and lower two single rods are cut off, and the upper single rod 10 is temporarily placed outside the excavation area or used as it is for excavation of the next pile hole.

Next, the remaining excavating rod 1 mounted on the cutting cradle 7 is mounted again on the excavator, the cutting cradle 7 is removed and moved, and while the cement milk is injected again, the remaining digging rod 1 is removed. And then cut it out in the same way.

The dimensions of the cutting support 7 are, for example, a groove width 200 mm sandwiching the rod shaft, a mounting width 400 mm, a height 100 mm, a length 2500 mm, and a rib or the like. The surface facing the rod axis is also considered as a smooth surface.

[0033]

According to the present invention, there is an effect that it is possible to surely prevent a drill rod-related disaster which has occurred once in several years.

Conventionally, the safety that has been ensured in the work procedure, which depends on attention, has been ensured by the improvement of the structure, and the excavation speed has not decreased due to the improvement of the stirring function of the excavation rod. There are various effects such as a tendency for the amount to decrease.

[Brief description of the drawings]

FIG. 1 is a block diagram of an embodiment of the method of the present invention.

FIG. 2 is a front view of the rod in which a part of the embodiment is omitted.

FIG. 3 is a front view of the rod, partially enlarged and partially omitted.

FIG. 4 is a conceptual diagram showing a relationship between a rod and a cradle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drilling rod 1a Shaft part 2 Kneading drum 3 Stirring bar 4 Pile hole 5 Upper flange 5a Rib 6 Lower flange 7 Drilling pedestal 10 Single rod

Claims (7)

[Claims] 1. A pile hole characterized by being able to slide and rotate on a contact surface with a rod and a cradle so that the rod and the cradle are not locked when the rod is separated, and to be free to slide. How to prevent accidents during excavation. 2. The method for preventing accidents during excavation of a pile hole according to claim 1, wherein the slidable and freely slidable rotation means that the rotational force applied to the rod is not transmitted to the cutting cradle. . 3. An upper end portion of a rod is provided with a flange for contacting a cradle, and a rod below the flange has an outer wall formed in a cylindrical shape over a predetermined length and has no projection. Pile hole drilling rod characterized by: 4. A disc-shaped upper flange is provided at an upper end of the rod for contacting a cradle, and a disc-shaped lower flange is provided at a predetermined length below the upper flange. A rod between a flange and a lower flange is formed in a cylindrical shape without any protrusion, and a lower surface of the upper flange and an upper surface of the lower flange are formed smoothly. 5. The pile hole excavating rod according to claim 4, wherein a reinforcing rib is provided on an upper surface of the upper flange. 6. The drilling rod according to claim 3, wherein a stirring rod and a kneading drum are fixed at a predetermined length to the rod below the lower flange. 7. The drilling rod according to claim 3, wherein the predetermined length is 0.5 m to 1.5 m.