JP2003301458A - Hollow pile driving method and driving machine used for it - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a construction method for reliably setting a hollow pile by changing to a setting method in accordance with the hardness of the ground. SOLUTION: Excavation is provided at a protruding end of a working rod inserted through a hollow pile from a lower end of the hollow pile, with a spiral wing having a diameter larger than the outer diameter of the hollow pile and a cap for opening and closing the open lower end of the hollow pile. Using a setting machine equipped with a head, in soft ground, in a state where the lower end of the hollow pile opening is closed by the cap, while excavating below the lower end of the hollow pile closing by rotation of the excavating head, the spiral wing is removed. The hollow pile is pressed into the ground by screwing it into the ground, and in hard ground, the lower end of the hollow pile is opened by the rotation of the drilling head while the lower end of the hollow pile is opened by the cap. The excavated earth and sand is sent into the hollow pile from the lower end of the opening while the rotation of the working rod suppresses the compaction of the excavated earth and sand in the hollow pile, thereby digging a vertical hole below the lower end of the hollow pile. A hollow pile driving method in which a hollow pile is pressed into a vertical hole.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hollow pile driving method for foundation piles and other hollow piles and a driving machine used for the hollow pile driving method.

[0002]

2. Description of the Related Art Conventionally, as a method for placing piles such as foundation piles,
At the tip of the auger screw inserted into the hollow pile, use an excavating blade having the same diameter as the inner diameter of the hollow pile, or a medium excavating machine or an external excavating machine equipped with an expanding blade having a diameter larger than the outer diameter of the hollow pile. While excavating below the hollow pile with the excavation blade by the rotation of the auger screw, the excavated earth and sand are transported upward through the hollow pile, and the hollow pile is press-fitted into the hole of the pre-dug. Type or outside digging type construction method is known, and a spiral wing is provided at the tip of the pile, and a screwed pile with the tip end face of the pile as the closed end or the open end is used, and the spiral wing is rotated by rotating the pile. A screw-type pile driving method in which a pile is screwed into the ground is known.

However, the former medium-drilling or outer-drilling method has the advantage that the piles can be press-fitted relatively easily regardless of whether the soil is hard or soft, but at the time of construction, a large amount of excavated earth and sand is loaded from the top of the hollow piles. However, not only is it expensive to process the waste, but it also has the drawback of deteriorating the working environment.

In the latter screw-in method, a large amount of excavated soil is not discharged, and the drawbacks associated therewith can be eliminated, but since it is a type that rotates the entire pile, the ground that is received on the pile peripheral surface as the depth increases As the frictional force increases, the press-fit resistance from the consolidated ground in the closed end increases, and the press-in resistance due to the consolidated sand in the pile increases in the open end.Still, it is relatively easy to screw in soft ground, but hard ground It's almost impossible to screw in.

[0005]

The first invention of the present application responds immediately to changes in the properties (hard or soft) of the ground during the driving,
It is an object to provide a driving method capable of always driving a hollow pile by changing the driving method suitable for that timely.

A second object of the present invention is to provide a driving method capable of driving a hollow pile having a high supporting force,

An object of the third invention of the present application is to provide a hollow pile driving machine which can effectively carry out the first invention.

[0008]

In order to achieve the above-mentioned object, the first invention of the present application is such that a work rod inserted into a hollow pile has a protruding end from the lower end of the hollow pile having a diameter larger than the outer diameter of the hollow pile. Using a placing machine detachably provided with a drilling head having a spiral blade and a lid for opening and closing the opening lower end of the hollow pile,
In the soft ground, in a state where the hollow pile opening lower end is closed by the lid, the spiral blade is screwed into the ground while excavating the lower part of the hollow pile closed lower end by the rotation of the excavation head, whereby the hollow pile is formed. Pressing into the ground, in the hard ground, with the lid removed and the hollow pile opening lower end opened, excavation below the hollow pile open lower end by rotation of the excavation head while excavating earth and sand from the open lower end to the hollow pile While feeding into the inside, by suppressing the consolidation of the excavated earth and sand in the hollow pile by the rotation of the working rod, the vertical hole is pre-drilled below the lower end of the hollow pile, and the hollow pile is pressed into the vertical hole, After press-fitting the pile to a desired depth, leaving the excavation head in the ground to pull out the work rod from the hollow pile, propose a hollow pile driving method,

According to a second aspect of the present invention, the lid of the excavating head in the first aspect of the present invention is formed into a cap shape that can be inserted into and removed from the lower end of the hollow pile opening, and the hollow pile is press-fitted to a desired depth and then the hollow pile opening is formed in the cap-shaped lid. Providing a hollow pile driving method, in which the lower end is fitted and the hollow pile opening lower end is closed to leave the excavation head in the ground, and the work rod is pulled out from the hollow pile.

According to the third invention of the present application, in a construction in which a rotary driven working rod is inserted into a hollow pile, a working blade for suppressing the consolidation of earth and sand in the hollow pile is projected on the outer peripheral surface of the working rod. The excavation head is detachably connected to the projecting end of the working rod from the lower end of the hollow pile by locking means that can be engaged and disengaged from the outside, and is connected to the excavation head from the outer diameter of the hollow pile. Is also provided with a lid for opening and closing the large-sized spiral blade and the lower end of the hollow pile opening, and a lid opening / closing drive means that can be driven and operated from the outside to bring the lid into and out of contact with the lower end of the hollow pile opening. We propose a hollow pile driving machine.

The above-mentioned "working blades for suppressing the consolidation of earth and sand in the hollow pile" of the working rod in the third invention of the present application mean continuous screw blades for carrying sand and sand, and a continuous small diameter screw for stirring sand and sand provided over the entire length of the working rod. The blade includes a blade, a stirring propeller blade, a composite blade including a stirring propeller blade and a screw blade for two or three turns, and various blades. Embodiments of the present invention will be described below with reference to the drawings.

[0012]

EXAMPLES For convenience, a hollow pile driving machine will be described first. In FIG. 1, a mast (2) is vertically supported on a front end of a base machine (1), and guide rails (3) and (3) laid along the entire length of the mast (2) are attached to a holder (5).
A wire rope (9) that hangs from a top sheave block (8) while supporting a rotation drive unit (4) on which a motor (6) and a speed reducer (7) are mounted so as to be vertically slidable.
And hangs up and down freely with the holder (5) of the drive part (4) and the earth hopper (10) connected to it.
The upper end of the hollow pile (11) is detachably connected and suspended to the lower end of the hopper (10), and the upper end of a working rod (in this example, auger screw) (12) inserted into the hollow pile (11) is attached. It penetrates through the hopper (10) and is connected to the output shaft of the drive unit (4).

The auger screw (12) has a continuous screw blade (13) for conveyance as a blade for suppressing soil compaction, which projects over the entire length of the rod. The lower end of the rod has a small head shaft (as shown in FIG. 2). 14) is concentrically connected, and a drilling head (15) having a spiral wing and a lid is detachably attached to the end of the head shaft (14) protruding from the lower end of the hollow pile (11).

The excavation head (15) is as follows. In FIG. 2, an angled plate-shaped excavating blade (17) is projectingly provided on the lower surface of the closed bottom plate of the hollow short cylindrical head body (16) having a diameter smaller than the outer diameter of the hollow pile (11), A short cylindrical cap-shaped lid (18) having an inner diameter that can be rotatably fitted to the lower end of the opening of the hollow pile (11) is continuously provided, and the main body (16) and the outer peripheral surface of the cap-shaped lid (18) are connected to each other.
Double spiral blade (1 with a diameter larger than the outer diameter of the hollow pile (11)
9) and (19) are projected. Reference numeral (16 ') is a through hole opened at the center of the bottom plate of the head body (16).

As a structure for attaching and detaching the excavating head (15) as described above, first, a conical pivot (20) is provided so as to project from the center of the lower end surface of the head shaft (14), and the head shaft (slightly above it) ( 14) A pair of locking single-acting small hydraulic cylinders (21), (21) are provided on the outer peripheral surface so as to project in the diametrical direction, and piston rods (22), (2) thereof are provided.
2) is directed outward as a lock pin, and on the other hand, in the center of the inner surface of the closed bottom plate of the head main body (16), there is installed a bowl-shaped pivot receiver (23) with which the pivot (20) engages, On the peripheral wall of the head body (16), lock holes (24), (24), which are elongated holes in the circumferential direction, are formed at positions corresponding to the piston rods (22), (22) of the cylinder. By engaging the pivot (20) with the pivot receiver (23), the excavation head (15) is centered with respect to the head shaft (14), and in that state, the piston rods of both hydraulic cylinders (21), (21) are positioned. (2
2) and (22) are locked in the lock holes (24) and (24), the excavating head (15) is moved to the auger screw (1).
2) Auger screw (1
2) It will be locked concentrically at the lower end. The auger screw (12) is attached to the tip of the pivot (20).
A solidified liquid injection hole for cement milk or the like that is pressure-fed through the rod and the head shaft (14) is provided and communicates with the through hole (16 ').

Denoted at (25) are four stabilizing single-acting hydraulic cylinders radially projecting at equal intervals on the outer peripheral surface of the upper end of the head shaft (14), and piston rods (26) thereof.
A roller (27) is rotatably attached to the tip of the ..., and the rollers (27) of each tip are rotatably abutted on the inner peripheral surface of the hollow pile (11) by extension of the piston rods (26). The drilling head (15) by the hollow pile (11)
Hold on the axis of. To further enhance the stability,
A plurality of stabilizing hydraulic cylinders (25) may be provided on the work rod (12) in multiple stages.

The lock cylinders (21), (21)
The pressure oil is supplied to and discharged from the stabilizing cylinders (25) through the pipes in the head shaft (14) and the auger screw (12) rod.

Opening and closing drive of the cap (18) with respect to the lower end of the opening of the hollow pile (11) is also used by the expansion and contraction drive means of the soil discharging hopper (10) in this example. This will be explained below. As shown in FIG. 3, the soil discharging hopper (10) has a rectangular cylindrical hopper outer cylinder (28) having an upper end opened and a lower end inclined with a bottom plate, and an upper end closed to be expandable and contractible, The hopper inner cylinder (29) with the lower end opening, and the earth and sand guide outer cylinder (a cylinder with both ends opening having the same inner diameter as the hollow pile (11) at the center position in one hopper outer cylinder (28) ( 30) is attached to the inclined bottom plate so that the upper end of the guide cylinder (30) protrudes into the upper part of the hopper and the lower end protrudes downward of the inclined bottom plate, and the sand guide is provided at the center position of the other inner cylinder (29) of the hopper. The inner cylinder (31) is attached by ribs (32), and the guide inner cylinder (31) is slidably engaged with the guide outer cylinder (30). (33) and (33) are the hopper inner cylinder (2
9) A hydraulic cylinder for expanding / contracting the hopper and for opening / closing the lid, which is connected to the left and right side surfaces of the upper end of the piston rod (3
4) and (34) are connected to the hopper outer cylinder (28).

(35) is a discharge port on the front surface of the lower end of the hopper outer cylinder (28), and (36) is a lid for opening and closing the discharge port (35), which is opened and closed by a hydraulic cylinder (37).

The upper end surface of the inner cylinder (29) of the earth discharging hopper (10) as described above is connected to the lower end of the holder (5) of the drive unit (4), and the protruding end of the earth and sand guide outer cylinder (30). A pile support cap (38) is fixed to the hollow pile (11) so that the upper end of the hollow pile (11) is detachably connected to the support cap (38), and the auger screw (12) inserted into the hollow pile (11) is The upper end of the inner and outer cylinders (3
1), extend through the inside of (30), and extend the extension end to the hopper (1
0) Penetrating upward inward and connected to the drive unit output shaft.
(39) and (39) are slide fittings of the drive unit (4) engaging with the guide rails (3) and (3), and (40) ... are slide fittings of the same soil discharging hopper (10).

Reference numeral (41) is a sheave block attached to the rear surface of the hopper outer cylinder (28), around which the drawn wire rope (42) is wound around a winch (not shown) of the base machine (1). .

An example of a hollow pile driving method using the hollow pile driving machine of the above example will be described. When placing hollow piles on the ground where the upper layer is soft and the lower layer is hard,
In the setting machine in a few states, the hopper outer cylinder (28) is lowered by the extension drive of the hopper expansion / contraction and cap opening / closing drive cylinders (33), (33), and the hopper (10) is extended. The hollow pile (11) is lowered to fit the lower end of the pile into the cap-shaped lid (18), thereby closing the open lower end of the hollow pile (11).

In that state, when the motor (6) is started to rotate the auger screw (12) and the excavation head (15) to start excavation into the soft layer, first, the excavation blade (1)
While excavating the ground below the hollow pile (11) closed lower end by 7), the spiral blade (1
9) and (19) are screwed in, and thereby the hollow pile (11) is pulled into the ground. Here, it is advisable to add tension to the drawing wire rope (42) to assist the press-fitting of the hollow pile (11).

When the drilling head (15) reaches the hard layer,
The lid opening / closing drive cylinders (33) and (33) are contracted to raise the hopper outer cylinder (28) and the hollow pile (11) so that the hollow pile lower end is appropriately separated from the cap-like lid (18). As shown in 1 and 2, the open lower end of the hollow pile (11) is opened. In that state, the auger screw (1
2) and the excavation head (15) are rotated to start excavation into the hard layer, the excavation blade (17) and the spiral blade (1)
While excavating the hard layer below the hollow pile (11) by 9) and (19), the excavated earth and sand are sent into the hollow pile (11) from the lower end of the opening, and the sent earth and sand are not consolidated in the hollow pile. Screw blade of screw (1
3) to facilitate the subsequent feeding of sediment into the hollow pile (11), thereby digging the vertical hole from which most of the excavated sediment has been discharged below the lower end of the hollow pile, and in the vertical hole. Then, the hollow pile (11) is squeezed and pressed into it with the cooperation of the wire rope (42).

The excavated earth and sand transported upward in the hollow pile (11) is stored in the hopper (10) through the earth and sand guides, the outer cylinders (31) and (30).

When the hollow piles (11) are press-fitted to a predetermined depth, the hollow piles (11) are extended by driving the lid opening / closing cylinders (33) and (33) under tension of the drawing wire rope (42). The lower end of the opening is fitted into the cap-like lid (18) so that the hollow pile is erected on the excavation head (15) with the lower end of the opening closed. Then, by supplying and discharging pressure oil, the lock cylinder (2
1), (21) and the stabilizing cylinders (25) are reduced and driven, respectively, and the piston rods (22), (22)
Are released from the lock holes (24) and (24) (unlocked), and the stabilizing rollers (27) are separated from the inner peripheral surface of the hollow pile (11), and then the upper end of the hollow pile (11) is supported by the pile. After detaching from the cap (28), the auger screw (12), the hollow pile (11) and the excavating head (15) are underground by winding the wire rope (9) together with the drive unit (4) and the hopper (10). Leave it on and pull it to the ground.

The cast hollow pile (11) has a larger diameter than that of the spiral blades (19), (19) in a closed state at the lower end.
Since the lower end is supported by the excavating head (15) that projects, the supporting force of the hollow pile (11) as a foundation pile is increased.

As another embodiment, a hollow pile driving machine in which a stirring rod having propeller blades and screw blades for two turns alternately provided in the longitudinal direction of the rod is inserted into the hollow pile is used. In the hollow pile driving method, when the opening bottom end of the hollow pile is opened in the hard layer to perform excavation, the excavated earth and sand fed into the hollow pile is agitated by the agitation rod to suppress consolidation, and Enables the subsequent sediment transfer into the hollow pile.

As still another embodiment, using the driving machine shown in FIGS. 1, 2 and 3, when the hollow pile (11) is press-fitted to near the final predetermined depth as in the above example, the hollow pile (11) is inserted there. ) Is lowered and the lower end of the hollow pile opening is rotatably fitted to the cap-shaped lid (18) of the drilling head, and then the head shaft (14).
While injecting cement milk from the lower end, drill head (1
The hollow pile (11) is press-fitted while rotating 5) for excavation. Depth Required Do this by hollow pile with soil cement mixed with cement milk and excavated soil (11)
A bulb having a diameter larger than that of the hollow pile is formed at the lower end of the.

[0030]

According to the hollow pile driving method of the first invention of the present application, in the driving step, in the soft ground, the lid is closed at the opening lower end of the hollow pile, and the spiral blade is screwed to excavate earth and sand to the ground. The hollow pile can be press-fitted without discharging, and when the ground turns hard, the lid is removed and the hollow pile opening lower end is opened to switch to the hollow pile press-fitting method. At this time, the excavated soil discharged to the ground at most can be limited to the excavated sediment on the hard ground, and in this way the hollow piles can be reliably laid in response to changes in the properties of the ground. In addition to being able to do so, it is possible to reduce the total amount of excavated sediment discharged to a small amount.

According to the hollow pile driving method of the second invention of the present application,
Since the hollow pile is closed by fitting the lower end of the opening to the cap-shaped lid and is mounted on the excavation head with the spiral wing having a diameter larger than that of the hollow pile, it is installed as a foundation pile. It is possible to realize an increase in supporting force when used.

According to the hollow pile driving machine of the third invention of the present application, the hollow pile driving method of the first invention can be effectively and reliably carried out.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view of a hollow pile driving machine according to the present invention.

FIG. 2 is an enlarged vertical sectional view of an excavation head portion.

FIG. 3 (a) is an enlarged vertical sectional side view of a soil discharging hopper portion. (B) (A) It is the sectional view on the AA line of a figure.

[Explanation of symbols]

11 hollow piles 12 Auger screw 13 screw blades 15 drilling head 18 Cap-shaped lid 19 spiral wings 21 Hydraulic cylinder for lock 22 Piston rod 33 Hydraulic cylinder for hopper expansion / contraction drive and lid opening / closing drive

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuo Yamazaki             1293 Amado-cho, Hanamigawa-ku, Chiba-shi, Chiba Sanwaki             Material Chiba Factory F-term (reference) 2D050 CA02 CB07 EE14

Claims (3)

[Claims] 1. A work rod inserted into the hollow pile has a spiral blade having a diameter larger than the outer diameter of the hollow pile and a lid for opening and closing the open lower end of the hollow pile at the protruding end from the lower end of the hollow pile. Using a placing machine with a removable drilling head, in the soft ground, while the lower end of the hollow pile opening is closed by the lid, excavating below the closed bottom end of the hollow pile by rotating the drilling head. The spiral wing is screwed into the ground, and thereby the hollow pile is press-fitted into the ground.In the hard ground, the hollow pile is rotated by the excavation head with the lid removed and the hollow pile opening lower end opened. While excavating the lower part of the open lower end, it sends the excavated earth and sand into the hollow pile from the open lower end and suppresses the consolidation of the excavated earth and sand in the hollow pile by rotating the working rod, thereby forming a vertical hole below the lower end of the hollow pile. Dig into the vertical hole The hollow pile is pressed, after press-fitting the hollow pile to the desired depth, pull the working rod from the hollow pile, leaving the drilling head into the ground, the hollow pile 設工 method. 2. The lid of the excavation head is formed into a cap shape that can be freely inserted into and removed from the lower end of the hollow pile opening, the hollow pile is press-fitted to a desired depth, and then the lower end of the hollow pile opening is fitted to the cap-shaped lid. The hollow pile driving method according to claim 1, wherein the working rod is pulled out from the hollow pile while leaving the drilling head in the ground with the lower end of the pile opening closed. 3. A structure in which a rotary driven working rod is inserted into a hollow pile, and a working blade for suppressing the consolidation of earth and sand in the hollow pile is projectingly provided on an outer peripheral surface of the working rod, At the protruding end from the lower end of the hollow pile of the working rod, the excavating head, by the locking means capable of engaging and disengaging from the outside,
Removably connected, the excavating head is provided with a spiral blade having a diameter larger than the outer diameter of the hollow pile and a lid for opening and closing the opening of the hollow pile opening, and the lid is provided with the hollow pile opening. A hollow pile driving machine equipped with a lid opening / closing drive means that can be driven and operated from the outside so as to be brought into contact with and separated from the lower end.