JPH11229740A - Subsoil excavation method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To substantially reduce a noise or a vibration due to a shock at the time of excavation by applying the constitution that an excavation device suspended with a crane truck is provided with a fixing means for the internal wall of a casing, and installing a bucket type excavation device via a lifting means. SOLUTION: A casing 8 is press fitted into the subsoil 7 by use of a jack 6, and an excavation device 3 suspended with the wire rope 2 of a crane truck an connected to a hydraulic pressure feed hose 4 is inserted in the casing 8. The excavation device 3 has lock teeth 15 pressed to the inner wall of the casing 8 on the operation of a hydraulic cylinder 14 on a support block 9, thereby being fixed. Furthermore, a base body 17 is lifted on the operation of a lifting hydraulic cylinder 16, guided by the fitting slide motion of a guide tube 19 and a guide rod 20, and a bucket 18 is turned up and down via a hydraulic cylinder inside the bas body 17 for an excavation work. Excavation soil in the bucket 18 is discharged so that the whole of the excavation device 3 is pulled out to a position outside the casing 8 with the lock teeth 15 released. According to this construction, a nose or a vibration due to a shock can be substantially reduced, compared with the case of the conventional hammer grab excavation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for excavating a prepared hole for placing ready-mixed concrete in the ground, for example, when constructing a concrete pile for foundation in the ground.

[0002]

2. Description of the Related Art In recent years, construction work of foundation piles in cities and urban areas is often performed by an all-casing method because of its advantages such as low noise and vibration and small construction space.

[0003] This construction method is performed according to a procedure schematically shown in FIG.

That is, as shown in FIG. 1A, a cylindrical casing tube c is inserted into a ground b using a push-in and pull-out jack a.

[0005] As shown in (B), a hammer grab (excavator) d suspended from a self-propelled crane truck or the like is dropped into the casing tube c by its own weight, and the tube c
The ground b inside is excavated and the excavated soil is discharged to the outside.

This excavation operation is performed while gradually pushing the casing tube c to excavate a pilot hole having a required depth. When it is necessary to drill a deep pilot hole, a new tube is joined to the upper end of the casing tube c.

[0007] Then, as shown in (C), after inserting a reinforcing rod cage e into a pilot hole in the casing tube c,
(D) As shown in FIG.
Is installed.

[0008] Finally, as shown in (E), if the jack a is turned over, the casing tube c is pulled out, and the poured fresh concrete f is hardened and cured, the foundation pile g made of reinforced concrete is placed in the ground b. Is constructed.

[0009]

In the above-mentioned all casing method, if the pilot hole in the casing tube c is excavated by using the hammer club d, it is necessary to repeatedly pull up the hammer club d and drop it, and only the own weight is required. This is a problem of low excavation efficiency and poor work efficiency.

[0010] In particular, when the ground is hard, the hammer club d rises due to the reaction force during excavation, and the excavation efficiency is further reduced.

In order to solve this problem, a hammer club d
Although it is conceivable to increase the weight of the vehicle, it is not preferable because this not only causes a large load to be applied to the winch or the like of the crane truck, but also increases the impact force at the time of dropping and increases vibration and noise. .

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has been made to prevent the generation of noise and vibration, suppress the reaction force during excavation, and greatly improve excavation efficiency. It is intended to provide a method and apparatus.

[0013]

In order to achieve the above object, the present invention provides a method for excavating a ground by inserting a cylindrical casing tube into the ground and excavating the ground therein. After inserting the excavating means suspended on a wire rope such as a crane truck into the casing tube, by repeating the work of fixing this inside the casing tube and the work of lowering the excavating means after the fixation,
It is characterized by gradually excavating the ground in the casing tube.

According to another aspect of the present invention, there is provided an excavating apparatus provided on a support base that can be inserted into and removed from a cylindrical casing tube inserted into the ground, and presses an inner surface of the casing tube. Thereby, there are provided restraint means for fixing the support base in the casing tube, elevating means provided downward on the support base, and excavating means attached to the lower end of the elevating means so as to be vertically movable. .

In the above-mentioned excavator, the restraining means comprises at least one pair of hydraulic cylinders provided to face each other so as to be orthogonal to the inner surface of the casing tube, and a locking claw fixed to the piston rod. Is preferred.

It is preferable that the tip of the locking claw has a serrated surface having the same curvature as the inner surface of the casing tube.

Preferably, the elevating means is a plurality of hydraulic cylinders.

It is preferable that guide means are provided between the support base and the excavating means so as to be slidable up and down with each other.

It is preferable that a projection is formed integrally with the casing tube in a state-of-the-art casing tube inserted into the ground so as to prevent rotation of the locking claw.

According to the excavating method and apparatus of the present invention, the excavating means is fixed in the casing tube and then lowered to excavate the ground. There is almost no excavation and the excavation efficiency is improved.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows a ground excavation method and an excavator used for the same according to the present invention. A lower end of a wire rope 2 hanging down from an upper end of a self-propelled crane truck 1 has:
The excavator 3 of the present invention is suspended. Reference numeral 4 denotes a pressure oil supply hose to the excavator 3, which is wound around a roller 5 at an intermediate portion of the crane vehicle 1 and connected to a hydraulic source of the crane vehicle 1.

6 is a jack installed on the ground 7, 8
Is a casing tube inserted into the ground 7 by the jack 6.

As shown in FIG. 2 in an enlarged manner, the excavator 3 includes a restraining means 10 provided on an upper surface of a thick disk-shaped support block 9 which can be inserted into a casing tube 8, The lifting block 11 includes a lifting unit 11 vertically provided on a lower surface, and a bucket type excavating unit 12 provided at a lower end of the lifting unit 11. It is suspended by hanging on 2a.

As shown in the plan view of FIG. 3, the restraining means 10 has a pair of hydraulic cylinders 14 fixed to the upper surface of the support block 9 by fixing brackets 13 so as to face each other by 180 °. A locking claw 15 is fixed to the tip of each piston rod 14a protruding outward.

The tip of the locking claw 15 has a curved surface so as to be in close contact with the inner surface of the casing tube 8, and has a saw-toothed surface to prevent slippage.

Each hydraulic cylinder 14 is simultaneously supplied with pressure oil from a crane truck via any of a plurality of system-specific hydraulic hoses 4a in the pressure oil supply hose 4.

The lifting / lowering means 11 comprises a pair of vertically moving hydraulic cylinders 1 having upper ends fixed to the lower surface of the support block 9 near the outer peripheral end thereof at 180 ° apart in the circumferential direction.
6, the piston rods 16a project downward. Both of these lifting hydraulic cylinders 16 also have
Any system-specific hydraulic hose 4a in the pressure oil supply hose 4
, Pressurized oil from the crane truck is supplied at the same time.

The excavating means 12 has a circular base 17 having an outer diameter that does not interfere with the inner surface of the casing tube 8.
And a pair of buckets 18 pivotally mounted on both lower ends on both sides so as to be vertically rotatable, and a hydraulic cylinder (not shown) for driving both buckets 18 provided in the base 17. The whole 12 is suspended from the support block 9 by connecting the upper end of the base 17 to the piston rod 16a of each of the hydraulic cylinders 16 for lifting.

The hydraulic cylinder for driving the bucket 18 is supplied with pressurized oil from a crane truck via a system-specific hydraulic hose 4a.

Near the outer peripheral end of the support block 9, a pair of guide pipes 19 penetrating and fixed to the mounting portion of the lifting hydraulic cylinder 16 at a distance of 90 ° in the circumferential direction and opposed to each other are provided with guide rods. 20 are fitted so as to be slidable up and down, and their lower ends are fixed to the upper surface of the base 17 in the excavating means 12.

Thus, the excavating means 12 can be stably moved up and down by the pair of guide rods 20.

Next, an excavation procedure using the excavator 3 of the above embodiment will be described.

As described in the conventional example, first, the jack 6 is operated to insert the casing tube 8 vertically into the ground 7 to a predetermined depth.

Next, the excavator 3 suspended by the wire rope 2 of the crane truck 1 is inserted into the casing tube 8, and the bucket 18 is brought into contact with the ground in the casing tube 8, as shown in FIG. Thus, both hydraulic cylinders 14 are actuated to press the locking claws 15 fixed to the piston rods 14a against the inner peripheral surface of the casing tube. As a result, the entire excavator 3 is fixed in the casing tube 8 in an immobile state.

In this state, the hydraulic cylinders 16 for raising and lowering are operated to depress the excavating means 12, and at the same time, the hydraulic cylinders in the base 17 are operated to rotate both buckets 18 upward.

Thus, the ground 7 in the casing tube 8 is excavated.

For excavated soil, the piston rod 14a of the hydraulic cylinder 14 is retracted, the locking claw 15 is separated from the casing tube 8, and then the wire rope 2 is wound up. I do.

Thereafter, the excavator 3 is inserted into the casing tube 8 again, and the casing tube 8 is gradually pushed in while repeating the above-mentioned operation to dig the ground therein. Is excavated. When excavating a pilot hole having a depth exceeding the length of one casing tube 8, another casing tube is joined.

After the completion of the excavation of the pilot hole, the steps of inserting the reinforcing cage into the casing tube 8, placing the ready-mixed concrete, and extracting the casing tube 8 (all not shown) are performed in the same manner as described above. After that, ground 7
A foundation pile made of reinforced concrete will be constructed inside.

As described above, according to the excavation method using the excavator 3 of the above embodiment, the noise and vibration due to impact are extremely small as compared with the conventional excavation of the Hamamaglab type, and the construction can be carried out safely in the city area. be able to.

The excavator 3 is connected to the casing tube 8.
Since the excavation is fixed inside the bucket, there is no possibility that the bucket 18 will be lifted by the reaction force during the excavation, and the excavation efficiency is improved.

Furthermore, the weight is smaller than that of the conventional hammer club, and the winch and the like of the crane truck can be reduced in size.

The excavating means 12 moves up and down while being held by a pair of guide rods 20 inserted through the guide tube 19 fixed to the support block 9, so that the excavating means 12 can be stably moved up and down. The excavating means 12 does not tilt.

The present invention is not limited to the above embodiment.

In the above embodiment, the hydraulic cylinders 14 of the restraining means 10 are paired. However, when the casing tube 8 has a large diameter and requires a large fixing force, a plurality of pairs, for example, two pairs are provided at intervals of 90 °. Is also good.

A hydraulic motor 21 as shown in FIG. 5 is provided in place of the bucket 18, and the earth bucket 22 attached to the rotating shaft is rotated while being pushed, and the earth and the like are scraped into the earth bucket 22 to remove the ground. You can also drill. In this case, excavation can be effectively performed even when the ground is extremely hard. In the case of using such a hydraulic motor 21, since a relative rotational force is generated particularly between the locking claw 15 and the casing tube 8, the projection 23 may be provided integrally with the casing tube 8 as shown in FIG. I just need. In this embodiment, the projection 23 has a triangular shape, and the locking claw 15 can be guided to an appropriate position, so that the fixing is more reliable.

The casing tube 8 can also be applied to one that is inserted into the ground by a rotary pushing device.

The present invention can be applied to the excavation of the preparatory hole for constructing the foundation pile, for example, the excavation of the preparatory hole for driving a pile, or the simple hole for erecting a column.

[0050]

(A) According to the method of the first aspect, efficient excavation can be performed without generating noise or vibration as in the conventional Hamaglav type.

(B) According to the device of the second aspect, the above method is easy to carry out, and since all the restraining means, the elevating means, and the excavating means are provided on the support base, the apparatus is simplified and the size is reduced. The weight can be reduced.

(C) According to the third aspect, the structure of the restraining means is relatively simple and a large restraining force can be obtained.

(D) According to the fourth aspect, the restraining force of the supporting base is further increased.

(E) According to the fifth aspect, the pressing force of the excavating means by the elevating means can be increased, and the excavating efficiency can be improved.

(F) According to the sixth aspect, the excavating means moves up and down stably, which facilitates excavation.

(G) According to the seventh aspect, the locking claw is fixed at a reliable position, and the stopping force against the rotational movement force is increased.

[0057]

[Brief description of the drawings]

FIG. 1 is an overall schematic diagram showing a procedure according to the present invention.

FIG. 2 is a front view of the entire excavator.

FIG. 3 is an enlarged plan view of the same.

FIG. 4 is also a front view at the time of excavation.

FIG. 5 is a front view of another embodiment during excavation.

FIG. 6 is an enlarged perspective view of a casing tube and a locking claw.

FIG. 7 is a schematic view showing a procedure of constructing a foundation pile using a conventional Hamaglav excavation method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crane truck 2 Wire rope 2a Hook 3 Drilling device 4 Pressure oil supply hose 5 Roller 6 Jack 7 Ground 8 Casing tube 9 Support block (support base) 10 Restraining means 11 Elevating means 12 Excavating means 13 Fixture 14 Hydraulic cylinder 14a Piston rod 15 Locking Claw 16 Elevating Hydraulic Cylinder 16a Piston Rod 17 Base 18 Bucket 19 Guide Tube 20 Guide Rod 21 Hydraulic Motor 22 Earth Basket 23 Projection

Claims (7)

[Claims] 1. A method for excavating a ground in which a cylindrical casing tube is inserted into the ground, and excavating means suspended from a wire rope such as a crane truck is inserted into the casing tube. A method for excavating the ground, characterized in that the ground inside the casing tube is gradually dug by repeating the operation of fixing the inside of the casing tube and the operation of lowering the excavating means after the fixing. 2. A restraint which is provided on a support base which can be inserted into and removed from a cylindrical casing tube inserted into the ground, and which fixes the support base within the casing tube by pressing an inner surface of the casing tube. A ground excavation apparatus comprising: means, elevating means provided downward on the support base, and excavating means attached to a lower end of the elevating means so as to be vertically movable. 3. The restraining means comprises at least one pair of hydraulic cylinders provided to face each other so as to be orthogonal to the inner surface of the casing tube, and a locking claw fixed to the piston rod. The ground excavator according to claim 2. 4. The ground excavator according to claim 3, wherein a tip of the locking claw has a saw-tooth surface having the same curvature as an inner surface of the casing tube. 5. The excavator for ground according to claim 2, wherein said lifting means comprises a plurality of hydraulic cylinders. 6. The excavator for ground according to claim 2, wherein guide means are provided between the support base and the excavating means so as to be slidable up and down with each other. 7. A casing tube which is inserted into the ground and has a projection formed integrally with the casing tube to prevent rotation of the locking claw. A ground excavation device according to any one of the above.