JP3827309B2 - Auxiliary pile method and embedded pile method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an auxiliary device used for pile foundation work by an embedded pile method at a construction site or the like, and an embedded pile method using the auxiliary device.
[0002]
[Prior art]
Previously, the construction method for building pile foundations was exclusively driven by the ready-made concrete piles, but due to changes in social conditions, noise and vibration during construction were severely regulated. I rarely see driving-in work. At present, the built-in pile method of pre-made piles with less noise and vibration is the mainstream of pile foundation work in general towns.
[0003]
FIG. 5 is a diagram for explaining a conventional buried pile method using the above-mentioned ready-made pile. In this embedded pile method, (a) First, a main pillar 2 (also referred to as a leader) is set up in such a way that a hole reaching a vertical support layer for embedding a pile in advance is supported vertically by a base machine 1 such as a crane. .) Is a drilling drill 4 (screw auger or the like) of an earth auger 3 (prime mover) slidably attached to a guide post provided along the center of the main pillar 2 and is inserted into a steady-state prevention device 5. (B) Cement milk 7 (milk-like product in which cement is melted with water) is poured into the excavation hole 6 from which the excavation drill 4 has been pulled out. (Iii) A concrete or steel ready-made pile 9 is built in the base machine 1 and (d) further cement 41 is mixed in to solidify the soil around the ready-made pile 9. No, it is a method that.
[0004]
Moreover, there exists a cast-in-place pile construction method applied to a large-scale pile foundation as another construction method of pile foundation construction (for example, refer nonpatent literature 1 or nonpatent literature 2).
[0005]
This is a method of digging a hole for making a pile in the field in advance, then putting a rebar into the hole and pouring the concrete into a reinforced concrete pile. Since piles are manufactured on site, transport of the piles is unnecessary, and it has the feature that large diameter piles that support large-scale buildings can be constructed relatively easily. On the other hand, it is necessary to use a casing (sheath tube) or to use a large amount of muddy water having a large specific gravity in order to prevent a hole dug in advance from collapsing.
[0006]
One of the cast-in-place pile methods is an all-casing method using an all-casing excavator. And there is a steel pipe with a special joint (referred to as a casing tube) used in the all-casing method, but this is a double structure made of steel plates with rib reinforcement to protect the hole wall, and is highly resistant to twisting and damage. Special.
[0007]
Generally, the casing is a cylinder inserted into the hole so that the hole of the concrete pile does not collapse, and is usually made of iron plate or steel pipe. In large-scale construction work, a large crane such as a 100-ton crane is used to insert and remove the casing while rotating it. This casing is at most about 3 m deep, and the deeper part is the specific gravity of swollen bentonite or the like. It is normal to drill while using large mud.
[0008]
Patent Document 1 below describes a hanging leader type pile driving machine that is currently becoming mainstream because a normal 20 to 50 t crane class crane can be used as a base machine.
[Patent Document 1]
Japanese Patent Publication No. 2-4732 [Non-Patent Document 1]
“Encyclopedia of Architecture and Civil Engineering” by ACE Network, Saitosha Co., Ltd., published on March 25, 1994, p. 130-131, p. 147
[Non-Patent Document 2]
Taisei Construction Technology Development Department, “Encyclopedia of Architecture and Civil Engineering”, Nihon Jitsugyo Publishing Co., Ltd., published April 25, 1991, p. 318
[0009]
[Problems to be solved by the invention]
However, a base machine 1 such as a crane of 20 to 50 tons used at a general construction site as shown in FIG. 5, a main pillar 2, an earth auger 3, and an excavation drill 4 equipped thereon. In the conventional embedded pile construction method in which the ready-made pile 9 is embedded in the excavated hole 6 that has been excavated in advance, the wall of the excavated drill hole 6 is easily collapsed during or after the excavation drill 4 is pulled out, so that the work is very difficult. Not often.
[0010]
The present invention has been made in view of the above circumstances, and an auxiliary device for preventing the wall collapse of the excavation hole 6 in the embedded pile construction method so that the work of embedding the ready-made pile 9 can be performed efficiently and the auxiliary device. A new and efficient embedded pile construction method using
[0011]
[Means for Solving the Problems]
The present invention
(1) A steel pipe having an inner diameter through which an excavation drill can be inserted and a hook part provided on the outer periphery in the vicinity of the upper end opening part, and engageable with the hook part of the steel pipe so as to be detachable from the upper end opening part of the steel pipe And a sliding mechanism that is slidable with respect to a guide column provided on a suspended main column, and has an insertion hole through which the excavation drill can be inserted. The above object is achieved by providing an auxiliary device for an embedded pile method characterized by comprising a substantially annular cap.
[0012]
(2) An earth auger equipped with an excavation drill is slidably supported by a wire on a guide column attached to a main column suspended vertically by a base machine, and is slidable with respect to the guide column. A cylindrical monken is inserted into the excavation drill and suspended by a wire, and a substantially annular cap slidable with respect to the guide column is inserted into the excavation drill and suspended by a wire. A step of inserting the steel pipe into the excavation drill and attaching and fixing the cap to the upper end opening of the steel pipe; and lifting the main pillar together with the steel pipe to stand perpendicular to the pile driving position A step of vertically holding the excavation drill, the monken and the steel pipe fitted with the cap; and excavating the ground with the excavation drill of the earth auger, at the upper end of the steel pipe Striking the upper surface of the attached cap with the monken and driving the steel pipe into the ground; pulling out the drilling drill from the steel pipe after the completion of driving the steel pipe; and injecting cement milk into the steel pipe; and A step of building a ready-made pile inside, a step of lifting the steel pipe and pulling it out of the ground, a step of mixing cement into the cement milk around the ready-made pile and solidifying the soil around the ready-made pile, By providing an embedded pile method using the auxiliary device for embedded pile method described in (1) above, the above-mentioned problem is achieved.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EMBODIMENTS Embodiments of an embedded pile method auxiliary device according to the present invention and an embedded pile method using the same will be described with reference to the drawings.
[0014]
FIG. 1 is a perspective view showing the structure of an auxiliary device for embedded pile construction according to the present invention.
[0015]
FIG. 2 is a diagram showing a construction start state of pile foundation work using the auxiliary device for embedded pile method according to the present invention.
[0016]
3 and 4 are conceptual diagrams for explaining a part of the steps of the embedded pile method according to the present invention. In addition, the substantially same member as a prior art is shown with a same sign.
[0017]
First, the auxiliary device for embedded pile method according to the present invention comprises a combination of a steel pipe 20 and a steel cap 10 having a length (about 6 m to 12 m) that reaches the support layer as shown in FIG. .
[0018]
The steel pipe 20 has a cylindrical structure in which a convex hooking portion 21 is provided on the outer periphery in the vicinity of the upper end opening 22 and an inner diameter Φ into which a drilling drill (for example, a diameter of 450 mm) can be slowly inserted. The purpose of the steel pipe 20 is to prevent the wall collapse of the excavation hole 6 as will be described later, and it is driven simultaneously with excavation of the excavation hole 6 for embedding in the embedded pile construction method. Pulled out from inside.
[0019]
The cap 10 has a substantially annular shape, and engages with a latching portion 21 of the steel pipe 20 so as to be detachably attached to the upper end opening of the steel pipe 20 (on the lower side of the circumferential surface). It is hooked on the lower side of the convex portion of the hooking portion 21 of the steel pipe 20 with several bolts 12 attached at substantially equal intervals.) And a guide column provided on a hanging main column And a sliding mechanism 15 that is slidable, and has an insertion hole 18 through which the excavation drill can be gently inserted. The upper surface is a flat flange 13. The purpose of the cap 10 is to support the steel pipe 20 vertically and lift it, and to soften the hammering by the monken and prevent the upper end opening 22 from being deformed.
[0020]
Next, in the embedded pile method using the cap 10 and the steel pipe 20 as the auxiliary device for the embedded pile method, first, as shown in FIG. 2, the main pillar suspended vertically by the base machine 1 such as a crane. An earth auger 3 equipped with an excavation drill 4 is slidably supported by a wire with respect to a guide column 8 attached to 2, and a cylindrical monken 31 slidable with respect to the guide column 8 is A substantially annular cap 10 that is inserted into the drilling drill 4 and suspended by a wire and slidable with respect to the guide column 8 is inserted into the drilling drill 4 and suspended by a wire. And a process of
Inserting the steel pipe 20 through the excavation drill 4 and fixing the cap 10 to the upper end opening of the steel pipe 20;
The main pillar 2 is lifted together with the steel pipe 20 and vertically placed on a pile driving location (on a horizontal base 40 in which a hole for passing the steel pipe 20 is drilled), and the excavation drill 4, the monken 31 and the cap 10 are crowned. The step of holding the steel pipe 20 vertically is performed to obtain a state (A) as shown in FIG.
[0021]
Next, as shown in FIG.
(B) While excavating the ground with the excavation drill 4 of the earth auger 3, the upper surface of the flange 13 of the cap 10 which is attached to the upper end of the steel pipe 20 is hit with the monken 31 to drive the steel pipe 20 into the ground. Process,
(C) The step of removing the cap 10 from the steel pipe 20 after the driving of the steel pipe 20 and pulling out the drilling drill 4 from the steel pipe 20 and injecting the cement milk 7 into the steel pipe 20 is performed.
[0022]
Next, as shown in FIG.
(D) a step of building the ready-made pile 9 in the steel pipe 20 using the base machine 1;
(E) hoisting the steel pipe 20 with the base machine 1 (the work is simplified when the cap 10 is attached), and pulling it vertically from the ground;
(F) A series of steps consisting of a step of mixing cement 41 into the cement milk 7 around the ready-made pile 9 and solidifying the soil around the ready-made pile 9 is performed.
[0023]
The above-mentioned monken (drop hammer) refers to a weight used for driving a pile by pulling it with a winch in pile driving work, and the monken used in the present invention has a vertical hole in the center. Nakabori monken corresponding to the so-called “bamboo ring” having Moreover, as said ready-made pile 9 applied to the construction method of this invention, a prestress concrete pile (PC pile) and steel piles (H steel pile other steel materials) can be applied besides the conventional general concrete pile. .
[0024]
By the way, the steel pipe 20 according to the present invention is similar to the cast-in-place pile method casing in terms of the effect of preventing the wall collapse of the excavation hole, but embedding pile foundation work using a relatively small 50t or less crane as a base machine. It is used for the pile construction method and its usage is different. The length of the steel pipe 20 is about the length of the prefabricated pile 9 to be embedded (usually about 6 to 12 m), and the inner diameter Φ is such a dimension that the 450 mm excavation drill 4 is loosely inserted, for example. And it is the structure which does not pull out while turning a pipe like the casing of the cast-in-place pile construction method, but is directly lifted and pulled without turning the pipe and turning the pipe, realizing extremely efficient pile foundation work. It is.
[0025]
According to the present inventor's test, it was possible to drive five piles a day according to the embedded pile construction method of the present invention, although it was limited to two piles a day with one base machine. understood.
[0026]
As a precaution, the steel pipe 20 as an auxiliary device for the embedded pile method according to the present invention is not a hollow “pile”, but is intended to prevent the wall of the excavation hole from collapsing. It is built in 20 and poured out after injecting cement milk 7 into the steel pipe 20. In this regard, it is completely different from a concrete or steel cylindrical pile that is embedded as a pile.
[0027]
【The invention's effect】
Since the auxiliary device for embedded pile method according to the present invention and the embedded pile method using the same are configured as described above,
(1) In the embedded pile method, the wall of the excavation hole is prevented by driving the steel pipe of the auxiliary device at the same time as excavation.
[0028]
(2) The construction efficiency of the embedded pile construction method in the pile foundation construction of a construction site using a general base machine such as a crane of 50 tons or less is improved.
[Brief description of the drawings]
FIG. 1 is a perspective view of an auxiliary device for embedded pile construction according to the present invention.
FIG. 2 is a diagram showing a construction start state of pile foundation work using the auxiliary device for embedded pile method according to the present invention.
FIG. 3 is a diagram for explaining a part of the steps of the embedded pile method according to the present invention.
FIG. 4 is a diagram for explaining a part of the embedded pile method according to the present invention.
FIG. 5 is a diagram for explaining a process of a conventional buried pile method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Base machine 2 Main pillar 3 Earth auger 4 Drilling drill 5 Stabilizer 6 Drilling hole 7 Cement milk 8 Guide strut 9 Ready-made pile 10 Cap 11 Latching mechanism 12 Bolt 13 Flange 15 Sliding mechanism 18 Insertion hole 20 Steel pipe 21 Hang Stop 22 Upper end opening 31 of steel pipe Monken 40 Base 41 Cement Φ Inner diameter of steel pipe

Claims (2)

A steel pipe having an inner diameter through which a drilling drill can be inserted while a latching portion is provided on the outer periphery in the vicinity of the upper end opening,
A sliding mechanism that includes a latching mechanism that engages with a latching portion of the steel pipe and is detachably attached to an upper end opening of the steel pipe and that is slidable with respect to a guide column provided on a hanging main column. An auxiliary device for an embedded pile method, comprising a moving mechanism and a substantially annular cap having an insertion hole through which the excavation drill can be inserted at a central portion. A cylinder in which an earth auger equipped with an excavation drill is slidably supported by a wire to a guide column attached to a main column vertically suspended by a base machine so as to be slidable with respect to the guide column. A ring-shaped monken is inserted into the drilling drill and suspended by a wire, and a substantially annular cap that is slidable with respect to the guide column is inserted into the drilling drill and suspended by a wire; And a process of
Inserting a steel pipe through the excavation drill and fixing the cap to the upper end opening of the steel pipe; and
Hoisting the main pillar together with the steel pipe and standing vertically to the pile driving site, and holding the excavation drill, the monken, and the steel pipe fitted with the cap vertically;
Hitting the upper surface of the cap that is attached to the upper end of the steel pipe with the monken while drilling the ground with the drill drill of the earth auger, and driving the steel pipe into the ground;
Extracting the drilling drill from the steel pipe after the driving of the steel pipe and injecting cement milk into the steel pipe;
Building a ready-made pile in the steel pipe;
Lifting the steel pipe and pulling it out of the ground,
The embedding using the auxiliary device for embedded pile construction method according to claim 1, further comprising: mixing cement into the cement milk around the ready-made pile to solidify the soil around the ready-made pile. Pile method.

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