JPH05106223A - Non-sludge withdrawal work-executing device for foundation pile, and non-sludge withdrawal work executing method for foundation - Google Patents

Abstract

PURPOSE:To enable a foundation pile to be driven into with non-oscillation, non-noise, and complete non-sludge withdrawal by arranging a plurality of salient strips on the periphery of easing, and by arranging consolidation shoes to be set adjacently to the upper side of an auger head. CONSTITUTION:A foundation pile work executing device is composed of an auger head 2 with an earth pressing edge 2c formed at the peripheral edge of a spiral screw wing 2b, and a cylindrical casing 3 for fitting the auger head to rotate it. In the work executing device, on the periphery of the lower end section of casing 3, consolidation shoes 4a-4d are firmly fitted, and the periphery of the casing 3, a plurality of salient strips 5a-51 are arranged. The salient strips 5a-51 are arranged with fixed positive oblique angles and fixed negative oblique angles to be alternately applied to the central line of the casing 3. Then, the inner peripheral surface of a hole opened widely by the auger head 2 is more widely opened by the consolidation shoes 4a-4d, and is consolidated, and the inner peripheral surface of the hole is prevented from being destroyed, and non-sludge withdrawal can be completely performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for constructing a foundation pile for supporting a structure on soft ground without soil discharge, and a foundation pile using the above-mentioned device for soil elimination. It relates to the method of construction.

[0002]

2. Description of the Related Art The technique of driving foundation piles to support a structure on soft ground has been used since ancient times.
Since the beginning of modern times, technical improvements have been concentrated on high-efficiency construction using mechanical power. However, the noise pollution caused by pile driving has become a social problem in recent years, and the development of a vibration-free and noise-free foundation pile construction technique has been promoted.
Furthermore, soil removal is a difficult issue for construction in urban areas. Although this disposal of soil is not technically impossible, it requires a lot of labor and cost, and may cause traffic congestion around the workplace.

In order to meet the social demands of no vibration, no noise, and no soil discharge, a screw auger having a thick soil surface formed on the outer peripheral portion of the screw blade piece, casing, etc. is used for digging. At the same time, the technology of constructing a foundation pile while preventing the collapse of the hole circumference by firmly consolidating the hole peripheral wall by the action of the above-mentioned soil surface is being developed and researched, but in the hole expanded and expanded with a screw auger When inserting the casing or the pile, a large frictional resistance is generated between the casing and the pile and the inner surface of the hole, so that this inserting operation requires a large amount of power and a long working time. As a prior art closest to the present invention for reducing such a problem, Japanese Patent Laid-Open No. 56-146584 (Japanese Patent Publication No. 57-44794) "Foundation pile construction device" is known. The above-mentioned publicly known technology is one in which an advanced spiral auger head is attached to the lower end of a cylindrical casing while expanding / consolidating soil, but the expansion / consolidation of soil is completely achieved only by the auger head described above. Since it is not performed, a spiral ridge is provided on the outer peripheral surface of the cylindrical casing.

[0004]

In the above-mentioned known technique, since the spiral projection is provided on the outer peripheral surface of the casing, the projection acts as a screw conveyor, and some soil is discharged. The amount of this soil removal depends on the soil quality, but in any case it is not possible to carry out completely soil-free construction. The present invention has been made in view of the above circumstances, and provides a device and a construction method capable of performing a foundation pile for supporting a structure on a soft ground with no vibration, no noise, and no complete soil discharge. The purpose is to provide.

[0005]

The basic principle of the present invention created in order to achieve the above-mentioned object will be described in relation to the basic principle of the present invention.
The outline is as follows with reference to FIG. 1 corresponding to the embodiment. The auger head 2 is attached to the lower end of the casing 3 to expand and consolidate the soil while advancing. In the present invention, soil is a broad concept including sand, gravel, clay and mixtures thereof. Consolidation shoes 4a to 4d are arranged adjacent to above the auger head 2 and fixed to the casing 3. The maximum diameter of this compaction shoe is larger than the outer diameter of the auger head, and completes the consolidation finish while further expanding the inner peripheral surface of the hole where the auger head is expanded and consolidated.
As a result, the casing 3 needs only to take the role of transmitting the rotational force, and it is not necessary to have the function of the screw conveyor. However, it is necessary to maintain the concentric state with the hole while the compression shoe slides so as not to roughen the inner peripheral surface of the hole that has been subjected to the consolidation finish, and
It is desired to reduce the friction caused by the sliding as much as possible.

As a concrete configuration based on the above principle,
The soil-free construction apparatus according to the present invention assumes a reference cylindrical surface having a diameter D _0, is concentric with the reference cylindrical surface, and has a bottom circle diameter D.
An auger head base having a conical surface of ₁ <D _0, and a screw blade concentric with the reference cylindrical surface, having a soil edge along the reference cylindrical surface, and fixed to the conical surface of the auger head base. , A cylindrical casing fixed to the auger head base and having a diameter substantially the same as the bottom circle of the auger head base and concentric with the reference cylindrical surface, and adjacent to the auger head base, and around the casing. A fixed compaction shoe having an outer diameter dimension D ₂ > D ₀ and a plurality of protrusions fixed to the periphery of the casing and having a top surface along the reference cylindrical surface; , The plurality of ridges are parallel to each other at a constant positive inclination angle θ with respect to a line parallel to the center line of the casing on the development view of the outer peripheral surface of the casing, at equal intervals. Are arranged and that Parts being characterized in that it is arranged parallel at equal intervals form a certain negative slope angle -θ with respect to a line parallel to the center line.

In addition, according to the method for constructing non-discharging foundation piles of the present invention based on the above-mentioned principle, an auger head having a conical surface that expands upward and a spiral surface having a soil edge on the periphery is provided.
It is attached to the lower end of a vertical straight cylindrical casing, and a compaction shoe having a diameter larger than the outer diameter of the soil edge is fixed to the outer peripheral surface near the lower end of the casing, and the lower end of the casing. Fix a number of ridges inclined at a positive angle with respect to the vertical line and a number of ridges inclined at a negative angle to the outer peripheral surface other than the above part and rotate it to the upper end of the casing. The auger head is screwed into the ground while applying force, and the inner peripheral surface of the hole that the auger head expands into the soil is further expanded while consolidating with the above-mentioned compaction shoe to form a cylindrical compacted soil wall. The ridge formed on the casing is slid on the top surface of the ridge along the inner circumferential surface of the compacted soil wall to reduce rotational friction and supply rotational energy to the auger head and the compacted shoe, thereby eliminating discharge. When you make a hole in the soil that has a vertical cylindrical surface, A, characterized by preventing the collapse of the bore inner surface by the compaction soil walls.

[0008]

[Operation] When the above-mentioned soil-free construction method is carried out using the above-mentioned soil-free construction device, the screw blades of the auger head generate a propulsive force, and the conical auger head base takes the lead in expanding the soil. Consolidation, and the soil edge of the screw blade promotes consolidation of surrounding soil. Further, the consolidation shoe completes the consolidation of the soil to form a cylindrical consolidation soil wall.

The outer diameter of the casing provided with the ridge is smaller than the inner diameter of the compacted soil wall, and the circle drawn by the top surface of the ridge is almost the same as the inner diameter of the compacted soil wall. Rubbing with a small friction without roughening the inner surface of the compacted soil wall. As a result, there is no risk of destroying and collapsing the inner peripheral surface of the consolidated soil wall, and without suffering a large power loss due to friction,
The casing is guided so as to be concentric with the compacted soil wall.
And, the ridges alternately form positive and negative angles,
Since it does not form a spiral, it does not act as a screw conveyor, therefore without carrying the soil upward and discharging it,
Complete non-removal will be realized.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows one embodiment of a soil-free construction device for foundation piles according to the present invention, and FIG. 1 (B) is a vertical sectional view.
(A) is the AA sectional view. As shown in FIG. 1 (B), the device of this embodiment is used with its longitudinal direction set upright vertically. Therefore, in the following description, the upper and lower names will be used based on the posture (FIG. B) in this usage state.

A vertical right circular cylinder having a diameter D ₀ is assumed as a reference cylindrical surface. This reference cylindrical surface is a fictitious cylindrical surface assumed as a design reference. A base plate 2a of the auger head is constructed by forming a steel plate member having a circular cone having a diameter D ₁ slightly smaller than the above diameter D ₀ and having an apex facing downward and having an inverted conical surface. Around the auger head base 2a, a screw blade 2b made of a steel plate is welded and fixed, and the edge of the periphery is folded up along the reference cylindrical surface 1 to form a compressed soil edge 2c. To do.
A casing 3 made of a steel pipe having an outer diameter D ₁ <D ₀ is fixed concentrically with the auger head 2 composed of the auger head base 2 a, the screw blades 2 b and the soil edge 2 c configured as described above. This fixing is detachably attached by a bolt (not shown).

Four compaction shoes 4a, 4b, 4c and 4d are fixed around the lower end of the casing 3 so as to be adjacent to the bottom surface of the auger head base 2a. As shown in FIG. 1 (A), these compaction shoes have a circumferential length shorter than L / N. However, L is the outer peripheral dimension of the casing 3, and N is the number of installed compaction shoes and is an integer of 2 or more. That is,
Surrounding the casing 3 with a plurality of consolidation shoes, and
The compaction shoes are arranged separately from each other. As shown in FIG. 1 (B), the above-mentioned compaction shoe has a large diameter at the upper side and projects outward from the reference cylindrical surface, and has a small diameter at the lower side (close to the auger head) and has the above-mentioned reference diameter. It is located inside the cylindrical surface. The diameter D ₂ shown in FIG. 1A indicates the maximum outer diameter of a plurality of (four in this example) consolidation shoes, and D ₂ > D ₀ .

As shown in FIG. 1A, a large number (12 in this example) of ridges 5a to 5a are formed on the outer periphery of the casing 3.
5 l are arranged and fixed to the casing 3. As for any one of these, for example, the ridges 5a, as shown in FIG. 1B, the ridges 5a ₁ and 5a having a length equal to or less than 1 / N of the length of the casing 3 are provided. Are arranged in the vertical direction (axial direction of the casing 3, that is, axial direction of the reference cylindrical surface 1). Similarly to this, each of the ridges other than the ridge 5a is also configured to have a length of 1 / N or less of the length of the casing 3, and is arranged in the vertical direction and is vertically separated.

As shown in FIG. 1B, 12
The ridges 5a to 5l of the book are arranged in a line around the periphery of the casing 3. The twelve ridges 5a~5l spaced by twelve ridges 5a ₁ ～5L downwards ₁ (in this figure is it appears only six) may be sequence set surrounding the periphery of the casing 3 There is. Also, the twelve ridges 5a~5l ridges 5a ₃ upwardly spaced twelve of ~5l ₃ (in the figure appearing only six) are arrayed similarly. The development view is shown in FIG. The outline of the overall appearance is shown in Fig. 2.
Appears in (A). The line z-z shown in FIG. 3 is a line parallel to the center line of the cylindrical casing. Many ridges 5a
˜5l is a constant positive tilt angle θ with respect to the above line zz
Are arranged in parallel with each other. Also,
The large number of ridges 5a _{1 to} 5l ₁ and 5a _{3 to} 5l ₃ are the lines z-
They are arranged in parallel with each other so as to form a constant negative angle −θ with respect to z. As shown in FIG. 1A, the plurality of ridges 5a to 5l are arranged with their top surfaces aligned with a circle having a diameter D ₀ , that is, aligned with the reference cylindrical surface 1. The mortar feed pipe 6 is arranged along the center line of the casing 3 and the auger head 2, and the lower end of the mortar feed pipe 6 has an opening 6
It is a. Although the tip of the mortar feed pipe 6 of this example is open to the top surface of the conical auger head base 2a, the tip of the mortar feed pipe is not necessarily located at the apex of the auger head base 2a when carrying out the present invention. It does not have to be opened, and may be opened in the vicinity of the auger head 2.

Using the soil-free construction apparatus (FIG. 1) configured as described above, the soil-free construction method of the present invention was carried out.
An example will be described next with reference to FIG. The upper end of the casing 3 is attached to the rotary drive MD, and the circular arc arrow B
When it is rotated like the above, the screw blades 2b of the auger head 2 are screwed into the soil to generate a downward thrust. The conical auger head base 2a is pressed down into the soil by this propulsive force and the self-weight of the device, and the soil is expanded and advanced while consolidating. Along with this, the casing 3 vertically penetrates into the soil. The hole expanded by the auger head base 2a is further expanded while the compression shoe 4c is pressed against the inner peripheral surface of the hole, and the soil on the inner peripheral surface is further consolidated and solidified to form a cylindrical consolidation layer 8. The ridge 5 provided around the casing 3 (see FIG. 2A) rotates with the casing 3, and the top surface thereof slides on the inner peripheral surface of the consolidation layer 8. The consolidation layer 8 is expanded by the consolidation shoe 4 and has an inner diameter of about D ₂ . The diameter of the rotation locus circle on the top surface of the ridge 5 is the diameter D ₀ of the reference cylindrical surface. Therefore, the top surface of the ridge 5 slides while lightly touching the inner peripheral surface of the consolidation layer 8, does not receive a large frictional resistance, and there is no risk of collapsing the inner peripheral surface. Then, as described above, the top surface of the ridge 5 is lightly contacted with the inner peripheral surface of the consolidation layer 8, while the case 3 is guided so as to maintain the vertical posture. In this manner, the auger head 2 and the casing 3 enter into the soil while forming the cylindrical consolidation layer 8, so that this operation is performed completely without soil.

When the casing 3 is lowered to a predetermined depth, the casing 3 and the auger head 2 are hoisted by a crane device (not shown) while reversing the casing 3 in the direction opposite to the arrow B, and at this time, the mortar feed pipe 6 is opened. Pouring cement mortar into the hole, about 70 of the expanded hole
% With cement mortar. Continuing with Figure 2 (B)
As shown in Fig. 3, the ready-made concrete pile 10 is hung down in the cement mortar 9 in the expanded hole to solidify the cement mortar and the ready-made concrete pile 1
Plant 0. In this way, the placing of the prefabricated concrete pile 10 is performed without completely discharging soil, without generating the noise of the impact pile driver and without transmitting the vibration of the vibration pile driver to the surroundings. be able to.

Although illustration is omitted, after the casing 3 and the auger head 2 are lifted while injecting the cement mortar as described above, the reinforcing bar (even if it is a basket or a core material) is placed in the cement mortar in the expansion hole. It is also possible to construct a so-called cast-in-place pile by inserting the cement mortar into the cement mortar and hardening it. Even if it is constructed in this way, it is possible to construct foundation piles with absolutely no soil discharge and no noise or vibration.

As a further different embodiment, after the casing 3 and the auger head 2 are lifted while the cement mortar is being injected as described above, the auger head is removed from the casing, and the casing 3 is again hung down and placed in the expansion hole. It can also be inserted and the cement mortar solidified. When constructed in this manner, the casing 3 is buried in the ground, so that a cast-in-place pile that is strong and particularly strong against bending stress can be formed. In this embodiment, instead of suspending and embedding the casing 3, it is also possible to suspend and embed a steel pipe pile having substantially the same diameter as the casing 3.

[0019]

As is apparent from the above embodiments, when the soil-free construction method of the present invention is used to implement the soil-free construction method of the present invention, no vibration, no noise, and It has an excellent practical effect of being able to drive foundation piles without completely discharging soil.

[Brief description of drawings]

FIG. 1 shows an embodiment of a soil-free construction device for foundation piles according to the present invention, (B) is a longitudinal sectional view, and (A) is its A-
FIG.

FIG. 2 is a process explanatory view showing an embodiment of a soil-free construction method for foundation piles according to the present invention, in which (A) shows a state during excavation, and (B) shows a concrete pile after being laid. The state is drawn.

FIG. 3 is a development view for explaining an arrangement of a large number of protrusions in the above embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Standard cylindrical surface, 2 ... Auger head, 2a ... Auger head base, 2b ... Screw blade, 2c ... Consolidation edge, 3 ... Casing, 4, 4a-4d ... Consolidation shoe, 5, 5a-5
l ... ridges, 5a ₁ ~5l ₁ ... ridges, 5a ₃ ~5l ₃ ... ridge,
6 ... Mortar supply pipe, 6a ... Opening, 8 ... Consolidation layer, 9 ... Cement mortar, 10 ... Ready-made pile.

Claims (10)

[Claims] [Claim 1] assumes a diameter D ₀ becomes the reference cylindrical surface, with the reference cylindrical surface concentric with the auger head base diameter of the bottom circle having a D ₁ <D ₀ becomes a conical surface, the reference cylindrical surface concentric A screw blade fixed to the conical surface of the auger head base, having a compressed soil edge along the reference cylindrical surface, and having substantially the same diameter as the bottom circle of the auger head base, and concentric with the reference cylindrical surface. Then, a cylindrical casing fixed to the auger head base, a compaction shoe having an outer diameter dimension D ₂ > D ₀ that is fixed to the periphery of the casing so as to be adjacent to the auger head base, and A plurality of ridges fixed to the periphery and having a top surface along the reference cylindrical surface, and the plurality of ridges on the development view of the casing outer peripheral surface On the center line of the casing On the other hand, some of them are arranged in parallel and at equal intervals with a constant positive tilt angle θ, and the rest are fixed with a negative tilt angle − with respect to the center line.
A non-removal construction device for foundation piles, characterized by being arranged in parallel at equal intervals with θ. 2. The ridges whose lengthwise dimension is shorter than half the lengthwise dimension of the casing, are arranged such that the ridges are vertically separated from each other, and the ridges are opposed to each other in the lengthwise direction. The soil-free construction device for foundation piles according to claim 1, wherein the same inclination has different positive and negative angles. 3. The compaction shoe is a strip-shaped member that is provided so as to surround the casing, and has a circumferential length dimension that is shorter than half the circumferential dimension of the casing. The soil-free construction device for a foundation pile according to claim 1 or 2, wherein the compaction shoes are arranged in the circumferential direction and are spaced apart from each other in the circumferential direction. 4. The compaction shoe has a smaller diameter closer to the auger head base and a larger diameter farther from the auger head base. The outer diameter dimension D _{2 of the} large diameter portion is
The soil-free construction device for a foundation pile according to claim 3, wherein D ₂ > D ₀ . 5. A mortar feed pipe is provided in the auger head base and the casing so as to substantially coincide with the axis thereof, and the tip of the mortar feed pipe is located near the conical auger head. Characterized by being open,
The soil-free construction device for foundation piles according to claim 1. 6. An auger head having a conical surface that expands upward and a spiral surface that has a soil edge on the periphery is attached to the lower end of a vertical straight cylindrical casing, and the vicinity of the lower end of the casing. On the outer peripheral surface of the casing, a consolidation shoe having a diameter larger than the outer diameter of the soil edge is fixed, and on the outer peripheral surface other than the lower end portion of the casing, a positive angle with respect to a vertical line on the development view. Fix a number of ridges inclined at a negative angle and a number of ridges inclined at a negative angle, and screw the auger head into the ground while applying a rotating force to the upper end of the casing, The inner peripheral surface of the expanded hole is further expanded while consolidating with the above-mentioned compaction shoe to form a cylindrical compacted soil wall, and the top surface of the ridge provided on the casing is Sliding along the inner peripheral surface to reduce rotational friction, the auger It is characterized by supplying rotational energy to the soil and the compaction shoe to form a hole having a vertical cylindrical surface in the soil without discharging soil, and preventing the collapse of the inner surface of the hole by the compacted soil wall. Pile-free soil construction method. 7. The vertical cylindrical surface-shaped hole is formed by using a mortar feed pipe opening along the center line of the casing and the auger head and opening near the auger head. The earth-free construction method for a foundation pile according to claim 6, wherein the auger head and the casing are pulled up while being reversed while the mortar is being injected. 8. The mortar is poured into the hole in the vertical cylindrical surface, the auger head and the casing are pulled up to the ground and removed, and then the ready-made concrete pile is hung and planted in the mortar. The non-removable earth construction method for a foundation pile according to claim 7. 9. The mortar is solidified by raising the auger head and the casing to the ground while removing the auger head and the casing while injecting the mortar into the hole of the vertical cylindrical surface, and suspending and inserting the rebar into the mortar. A non-removable earth construction method for a foundation pile as set forth in claim 7. 10. The mortar is poured into the hole in the vertical cylindrical surface, and the auger head and the casing are pulled up to the ground and removed, and then, the mortar has the casing with the auger head removed or substantially the same as the casing. The method for soil-free construction of foundation piles according to claim 7, characterized in that a steel pipe pile having a diameter is hung down and the mortar is solidified.