JPH0941369A - Method of remodeling and reinforcing construction of pile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the bending strength and shearing yield strength of a pile by expansible fillers and a sheathed pipe unified with the pile by injecting the fillers into space between the sheathed pipe and the pipe and curing the fillers. SOLUTION: A steel pipe 3 is rotated and penetrated up to specified depth, pressure water is changed over to a stabilizing liquid and extraction and drilling processes are completed while filling the inside of a drilled hole, a sheathed pipe 2 is connected to an auger excavator 11 and faced to a section just above a pile A, and the pipe 2 is lowered while being turned, and revolved and penetrated to the pile A. The periphery of the pile A is excavated by a cutter 13 at a front end in the sheathed pipe 2, a ring 15 hermetically seals space between the front end of the sheathed pipe 2 and the outer circumferential surface of the pile A, and the inside of the space is supplied with fresh water from an upper section while preventing the intrusion of residual slime, etc., between the sheathed pipe 2 and the pile A. When the sheathed pipe 2 is penetrated up to specified depth, a detergent is introduced into the space and the inside of the space is cleaned, and expansible high-strength fillers are pressed-into and filled into the space between the sheathed pipe 2 and the pile A extending over the upper section from a place in a lower section, thus reinforcing the pile A by the cured layer of the fillers and the sheathed pipe 2, then remodeling the pile to a pile resisting bending and shearing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pile remodeling and reinforcing method for reinforcing the bending and shearing strength of a pile in the upper layer portion of the pile placed in the ground, that is, an already constructed pile. ,
Alternatively, the present invention relates to a construction method for imparting a required depth to a required depth and a required strength to an upper layer portion of a remaining pile after dismantling and removing a ground structure and a damaged pile.

[0002]

2. Description of the Related Art Foundation piles have great strength in the vertical direction, but are weak against bending and shearing forces due to horizontal forces generated by earthquake motion. When rebuilding a damaged building or scraping and building a building, the handling of existing foundation piles becomes a problem.

Even when considering the reuse of the piles left behind, it is very difficult to judge and verify the soundness of the piles, and there is a safety problem.

Even if a plan is made for the extension of piles, there is a difference in performance between the new and old piles, and there remains a problem in the design of the foundation structure.

Conventionally, several methods, which will be described later, have been used to modify and reinforce the piles, but each has its own advantages and disadvantages.

A) Excavating and removing the upper layer of the piles left behind,
Place new piles. In that case, the part where the existing pile is an obstacle will be pulled out and removed.

(B) Pull out all the remaining piles and place new piles.

C) A construction method in which the steel material is put inside the pile head of the existing pile and the concrete is filled.

D) A method of digging out the entire upper layer of the pile, covering the outer periphery of the pile with a steel pipe, and pouring a filler or concrete between them.

(E) Proposed examples such as a method of fitting a steel pipe to the outer periphery of an existing pile by striking without excavating, or a method of rotationally press-fitting a steel pipe with an excavation cutter inside is also found. In this case, there are some methods in which a filler is added and some methods are not.

[0011]

By the way, in the above-mentioned conventional construction methods, both the construction methods a) and b) further loosen the weak ground, which requires a great deal of cost and construction period, and generates industrial waste, noise, and vibration. There is.

In the case of the method (c), the strength cannot be greatly increased, and if cracks or the like occur in the pile body, the steel wire, steel rod, etc. in the pile body will be corroded, which is safe in the long term. It is difficult to plan new buildings, and there are major restrictions.

The method (d) has certainty, but excavation requires soil retaining work or the like on the outer periphery, and the depth at which it can be reinforced is limited, so that there are major problems in terms of cost and construction period.

The construction method (e) can be affirmed in terms of methodologies and there are experimental examples, but all have structural and strength problems, and construction methods are also unrealistic.

Further, when the pile construction method using cement milk or the like is adopted at the time of construction of the pile, it is almost impossible to fit the steel pipe, and the pile cement may be left over by cement cement, mud or the like. It has been pointed out that there is uncertainty in the integration of the steel pipe with the steel pipe, and there is no information that it has been put to practical use.

[0016] Therefore, the present invention does not pull out or dismantle the existing pile, and remodel it to the required depth for any pile, whether it is a damaged pile or a healthy pile. It can be reused without reinforcement, and even if it is necessary to add piles in the plan design of the upper building to be rebuilt, it is also possible to place the same type of piles and make similar modifications and reinforcements. , It is an object to provide a method of pile modification and reinforcement that enables effective planning and design of existing buildings by effectively utilizing existing piles.

[0017]

In order to solve the above problems, the invention according to claim 1 provides a steel pipe in which a cutter and a roller bit are mounted around a tip end portion having an inclination angle.
A hole drilling process in which a mixed pressure water and a control system are used to rotationally penetrate the upper outer periphery of the pile placed in the ground to form a circular hole around the pile to remove the drilling device, and After the drilling process, a steel sheath with a cutter and a blocking ring at the tip is rotatably penetrated into the part of the pile where the drilled hole is formed, and the gap between the pile and the sheath is washed, and the expansive high strength is applied to this gap. This method adopts a structure including a process of press-fitting a filler and integrating the pile and the sheath tube.

In the hole drilling process, when the steel pipe is rotated, the mixed pressure water jet is used together so that the hole can be smoothly drilled, and in order to prevent the torsion damage of the pile, the steel pipe is rotated and penetrated. Is controlled by the control system.

The cleaning of the gap between the pile and the sheath tube is performed by putting a cleaning agent in fresh water for cleaning.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings.

The method for modifying and reinforcing a pile of the present invention comprises two components. First, as shown in FIGS. 1 to 4, the first method is to drill holes in the outer peripheral portion of the upper layer of the pile A to be modified or reinforced. Device 1
The second step is to form a hole by using
As shown in FIG. 6, after the drilling step, the steel sheath 2 is rotatably penetrated into the portion of the pile A where the drilling is formed, and the sheath 2 and the pile A are filled with the expansive high-strength filler B. It is a process of integrating by press fitting.

1 to 3 show the structure of a hole drilling device 1 used for carrying out the first hole drilling step, and it has a larger diameter than the pile A and the outer peripheral surface of the pile A at the time of external fitting on the pile A. The tip of the steel pipe 3 forming a necessary gap between the steel pipe 3 and
A plurality of window holes 5 are arranged on the peripheral wall of the tip of the roller along the inclination of the inclination angle 4, and a roller bit 6 having an upside-down inverted truncated cone shape is rotatably attached to the portion of the window holes 5.

As shown in FIG. 3 (A), the roller bit 6 projects inward and outward from the steel pipe 3, and the inner diameters of all the roller bits 6 are set so as to be close to the outer diameter of the pile A. A friction cutter 7 is provided at a position on the tip side between the roller bits 6 so as to project from the inner and outer directions of the steel pipe 3 and the inclination angle 4 so that the inner peripheral surface of the steel pipe 3 has
A plurality of wire brushes 8 that are in sliding contact with the outer peripheral surface of the pile A are provided.

A plurality of steel spacers 9 are provided on the inner peripheral surface of the steel pipe 3 so as to be coaxial with the pile A when the steel pipe 3 is penetrated, and a circular slime is formed on the peripheral wall of the steel pipe 3. A discharge hole 10 is provided, and the nozzle 1 at the tip is further provided inside.
2a faces a position close to the roller bit 6, and a pressure water feed pipe 12 whose rear end is directly connected to the auger machine 11 is fixed.

FIG. 6 shows the structure of the sheath pipe 2 in the step of integrating the pile A and the sheath pipe 2, and the steel sheath pipe 2 is the steel pipe 3 described above.
The cutter 13 is fixed to the tip of the sheath 13 and has a plurality of spacers 14 for maintaining a coaxial state at the time of insertion into the pile A. The tip is slightly squeezed inward, and a ring 15 made of soft rubber or the like for sealing the space between the pile A and the sheath tube 2 is incorporated therein.

Next, the reinforcing method of the present invention will be described with reference to the accompanying drawings.

First, as shown in FIG. 1, the boring machine 1 is connected to an auger excavator 11 which moves up and down along a leader 17 of a working machine 16, and a steel pipe 3 is mounted directly on a pile A driven in the ground. The steel pipe 3 rotated by the activation of the auger machine 11 is lowered to penetrate the pile A.

FIG. 4 shows a state in which the steel pipe 3 has penetrated into the pile A by rotation, the tip of the steel pipe 3 has an inclination angle 4, and a roller bit 6 and a friction cutter 7 are provided at the tip portion in an arrangement along the inclination angle 4. Since the cement milk C and the earth and sand solidified on the outer peripheral surface of the pile A can be efficiently crushed, the jet of mixed pressure water is jetted from the nozzle 12a into the steel pipe 3 at the time of rotary penetration, and the slime is generated. Is discharged to the ground by the ascending flow of pressure water, and the outer peripheral surface of the pile A is cleaned by the sliding contact of the wire brush 8. The mixed pressurized water is water mixed with air and a viscous additive.

As shown in FIG. 4, after the steel pipe 3 has been rotationally penetrated to a predetermined depth, while the steel pipe 3 is being rotated, the pressure water is switched to a stable liquid to withdraw while filling the inside of the drilling hole to complete the drilling process. To do. Upon completion of this drilling step, an annular drilling hole is formed on the outer periphery of the upper portion of the pile A.

In the drilling process, the work machine 16 is equipped with the rotary penetration control system 18. This system 18 has a function of automatically measuring and recording the rotation torque, the penetration speed, the water pressure, etc. at the time of penetration of the steel pipe 3 and controlling the rotation penetration to prevent damage to the pile.

Examples of such a system include Japanese Patent Publication No. 54-31603 and Japanese Patent Publication No. 4-60 proposed by the present inventors.
No. 164, Japanese Examined Patent Publication No. 6-76692 and the like can be used, and these systems have been used in actual construction and have a good track record, and can be effectively used for implementing the construction method of the present invention.

Next, when the drilling process is completed, as shown in FIG.
The sheath pipe 2 is connected to the auger machine 11, the pipe 2 is directly above the pile A, the pile pipe A is lowered while rotating, and the pile pipe A is rotationally penetrated.

The sheath tube 2 is excavated around the pile A by the cutter 13 at the tip, and the ring 15 seals the gap between the tip of the sheath tube 2 and the outer peripheral surface of the pile A, so that the sheath pipe 2 and the pile A are separated from each other. Fill the gap with fresh water from the top while avoiding residual debris.

When the sheath pipe 2 is penetrated to a predetermined depth, a cleaning agent is put into the gap for cleaning, and in the final stage, the gap between the sheath pipe 2 and the pile A extends from the lower position to the upper portion of the expansive high-strength filler. B is press-fitted and the work is completed.

Expandable high-strength filler B hardens and expands, so that the sheath tube 2 and the pile A are integrated, and the pile A is reinforced by the hardened layer of the filler B and the sheath tube 2 and is strong against bending shear. Can be converted into piles.

When the piles are modified and reinforced by the construction method of the present invention, the damage degree and soundness of the existing piles are investigated,
Then, the pile design, the reinforcement, and the pile expansion corresponding to the design of the new construction are examined, and the pile design is summarized.

In the pile modification and reinforcement method according to the present invention, damaged piles, healthy piles, and piles to be added are made into safe and homogeneous foundation piles by the steel sheath and pipe design technology. The major feature is that it can be modified and reinforced. Remodeling,
The strength of the reinforced pile will be verified by vertical and horizontal tests.

[0038]

As described above, according to the present invention, after removing the aboveground structures and foundations, the pile heads of the remaining foundation piles are reinforced to the required depth and to the required strength. However, if it is necessary to reconstruct piles that can withstand reuse, and if it is necessary to add more piles, it is possible to construct foundation piles that are stable in terms of the basic structure without the difference between old and new by the same method. The features and effects are summarized below.

(I) It is possible to economically reuse the foundation pile by reinforcing and reinforcing the head portion of the foundation pile that remains.

(II) It is not necessary to pull out and dismantle the remaining foundation pile, which is a great effect in terms of construction period and economy.

(III) Emission of industrial waste is extremely small, and there is no noise and no vibration, so there is almost no pollution.

(IV) Since the piles are not pulled out or dismantled and removed, no harmful loosening of the ground or subsidence occurs.

(V) Since a flexible basic structure designing method can be adopted for a new plan or design, its application range is wide.

[Brief description of drawings]

FIG. 1 is a front view showing a set state of a steel pipe in which a hole drilling process is performed.

[Fig.2] Enlarged vertical section of steel pipe

3A is a cross-sectional view taken along the arrow AA of FIG.
(B) is a cross-sectional view taken along the arrow BB of FIG.

FIG. 4 is a vertical cross-sectional view showing a hole drilling process.

FIG. 5 is a front view showing a state in which a sheath pipe is set in which a sheath pipe and a pile are integrated.

FIG. 6 (A) is a longitudinal sectional view in which a sheath tube is rotationally inserted,
(B) is an enlarged vertical sectional view in which an expansive filler is filled therein,
(C) Enlarged sectional view showing the tip structure of the sheath tube

[Explanation of symbols]

 1 Drilling Device 2 Sheath Pipe 3 Steel Pipe 4 Inclination Angle 6 Roller Bit 7 Friction Cutter 8 Wire Brush 9 Spacer 10 Slime Discharge Hole 11 Auger Machine 12 Water Pipe 13 Cutter 14 Spacer 15 Ring 16 Working Machine 18 Rotation Penetration Control System

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Haruharu Funabiki 3-32-4404, Tomimatsucho, Amagasaki City (72) Inventor Yasuhiko Mamehata 8-5, Shiroyamadai, Hashimoto City

Claims (1)

[Claims] 1. A steel pipe, in which a cutter and a roller bit are mounted around a tip having an inclined angle, is rotationally penetrated into the upper outer periphery of a pile driven into the ground by using mixed pressure water and a control system, A drilling process for forming a circular drilling hole around the pile and removing the drilling device, and after the drilling process, a steel sheath with a cutter and a blocking ring at the tip is drilled for the pile. A method of remodeling and strengthening piles, which involves the steps of rotatingly penetrating the piled portion and cleaning the gap between the pile and the sheath pipe, and then press-fitting an expansive high-strength filler into this gap to integrate the pile and the sheath pipe.