JPH04179731A - Simplified underground continuous wall construction method - Google Patents

Abstract

PURPOSE:To prevent deformation or fracture of a wall by correcting excavation angles by a method wherein an excavation chain inclined to the side of an excavator is driven to form a ditch, forming a pair of walls, each of which is inclined outwardly from the upper edge thereof, through the ditch, and carrying out excavation using walings. CONSTITUTION:A leader 12 vertically provided before a driver's seat 11 is pivoted clockwise on a supporting shaft 15 by means of a hydraulic cylinder 16 fixed to the seat 11 to slightly incline a guide member 14 of a steel casing toward the side of an excavator 1. A driving part 18 is actuated to drive a chain 13 so that the ground surface 26 is excavated downwardly by excavation claws to form a ditch 21 corresponding to the inclined angle theta of the member 14. The member 14 is then lowered along the leader 12 and separated from the part 18 to recover the chain 13 only, leaving the member 14 in the ditch 21, so that walls 22, 23 are formed in the earth in such a manner that they are inclined outwardly from the upper edges thereof, Walings 24 are fixed between the walls 22, 23.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a simple underground continuous wall construction method in which a small-scale narrow continuous wall is formed by excavating underground using a chain saw, and in particular, This invention relates to a continuous underground construction method for parts in which excavation is performed by tilting a chain so that the surface is inclined.

[Conventional technology]

Conventionally, the packet method, pit method, etc. have been used as construction methods for continuously excavating narrow trenches, but with these methods, the excavation width is 40 to 50 CIl+ or more, which makes it difficult to Economical construction was difficult for large-scale construction projects, and advanced know-how based on engineering knowledge and construction experience, such as excavation technology and stabilizing fluid management, was required. Furthermore, in order to prevent the collapse of the ground during excavation, stabilizing liquid and guide walls were required, and it was difficult to excavate close to existing equipment. For this reason, the applicant of this patent previously proposed a simple underground continuous wall construction method described in Japanese Patent Application Laid-Open No. 1-250520. This construction method involves excavating underground using a chain saw, and forming a continuous wall through an arbitrary number of grooves. According to this construction method, narrow walls can be easily and economically formed without using stabilizers or guide walls, and construction can be performed close to existing buildings.

However, if a continuous wall is formed based on this construction method, especially if the wall is formed in the trench after the trench is formed vertically from the ground surface, the wall will be pushed downward from the ground surface due to the stress of earth pressure. As the angle increases, the wall becomes more inclined, and as a result, it becomes impossible to form a continuous wall having the original angle.

In addition, when a continuous wall is formed by a conventional construction method and then a construction excavation section is formed, the formed continuous wall may be deformed or deformed due to the stress of the earth pressure during or after excavation of the construction excavation section. There is a risk of it collapsing, making it unreliable.

[Problem to be solved by the invention]

Therefore, in order to eliminate the drawbacks of the above-mentioned conventional technology, the present invention focuses on the fact that the stress of the earth pressure varies depending on the depth underground, and corrects the excavation angle in advance and excavates to effectively prevent the negative impact on the continuous wall. The purpose of this project is to provide a simple continuous wall construction method.

[Means to solve the problem]

That is, in order to achieve the above object, the present invention tilts a digging chain installed in an excavator toward the excavator, rotates the digging chain in this tilted state, and excavates from the ground surface to underground. This feature is characterized in that a groove is formed by using a steel structure, and a wall is formed through a steel structure.

In addition, at least one pair of walls formed through the trenches excavated by the above-mentioned construction method are arranged in a V-shape on both sides of the construction excavation part, and the distance between the walls arranged in the 71-shape is arbitrary. The present invention is characterized in that the construction work is carried out by excavating the excavated part for construction through several erections.

[For production]

The present invention configured by the above-mentioned means forms a trench by excavating from the ground surface to underground with a digging chain installed in an excavator tilted toward the excavator, and a groove is formed through a steel structure to form a trench. Since a body is formed, the wall body has an inclination angle corresponding to the inclination angle of the excavation chain. Therefore, the wall is formed at an angle that is corrected from the ground surface to the angle that should originally be formed due to the stress of earth pressure.

Further, by forming at least one pair of walls formed at an angle in this way in a V-shape, and excavating a construction excavation part while interposing an arbitrary number of raised sides between the pair of walls, Deformation or collapse of the pair of walls during or after excavation due to earth pressure can be effectively avoided in advance.

〔Example〕

In order to further clarify the gist of the simple underground continuous wall construction method of the present invention, one embodiment will be described below with reference to the drawings.

The excavator 1 used to carry out this construction method has an elongated ladder 12 vertically installed in front of a driver's cab 11 on which an operator rides, and a guide member 1 on this ladder 12.
It has a guide member 14 which is supported so as to be movable up and down via 2a and 12b, and has a chain 13 in the form of an endless track attached to its circumferential surface so as to be movable. The leader 12 is connected to a support shaft 15 formed at the front end of the driver's cab 11 and the driver's cab 11.
The distal end of a hydraulic cylinder 16 fixed to the hydraulic cylinder 16 is supported by a fixed part 17, and is rotatable about the support shaft 15 by hydraulic operation of the hydraulic cylinder 16. Further, the guide member 14 is made of a steel casing in this embodiment, and a drive section 18 for driving the upper chain 13 to travel is disposed on the upper end side. Note that in this excavator 1, the guide member 1 is
A plurality of wire lobes 20 and 21 are stretched across the guide member 12a supporting the guide member 14, and the guide member 14 is raised and lowered by winding the wire lobes 20 and 21 using these winches. ing.

Then, as shown in FIG. 1, the excavator 1 having the above-described configuration is brought close to the existing equipment A, and the leader 12 is moved around the support shaft 15 by hydraulic operation of the hydraulic cylinder 16 as shown in FIG. The guide member 14 is tilted by rotating clockwise.

Note that the inclination angle θ of the guide member 14 is determined appropriately depending on the depth of the groove to be formed, since the stress of earth pressure is greater below the groove, but it is usually determined as shown in FIG. The angle may be approximately 1 to 2 degrees from the vertical line.

After inclining the guide member 14 in this manner, the drive unit 18 is driven to drive the chain 13 and the guide member 14 is lowered along the leader 12 by winding the winch. A large number of digging claws attached to the chain 13 excavate downward from the ground surface 26. The groove 21 thus formed is inclined in accordance with the inclination angle θ of the guide member 14.

After the trench 21 has been formed by the excavator 1, a wall is formed via the steel structure 21. This wall body separates the drive unit 18 from the guide member 14, releases the chain from the endless track state by removing a pin (not shown), and recovers only the chain 13 by driving the drive unit 18 again. The guide member 14 is left inside the guide member 21 . In this way, the steel casing forming the guide member 14 is used as a wall body, and a plurality of wall bodies are formed along the existing equipment A to form a continuous wall.

Next, using the construction method described above, a pair of continuous walls facing each other with a predetermined interval are formed in the ground in a V-shape, and excavation is performed between the two walls to form an excavation section for construction. do. At this time, as the earth's surface is gradually excavated, a plurality of ribs 24 are fixed from one wall 22 to the other wall 23, as shown in FIG. That is, after excavating to a predetermined depth between the pair of walls 22 and 23 to form the construction excavation part 25 of a predetermined depth, first, the first upright 24a is
The excavated part 2 for construction is fixed in the order of fixing a plurality of them from one wall body 22 to the other wall body 23, and then fixing a plurality of second uprights 24b after excavating to a predetermined depth.
5 are excavated and gradually formed downward, they are raised downward in order 24a, 24b, 24c, 24d...-
to be fixed.

If a continuous wall is formed using the construction method described above, even if each wall body 22° 23 is pressed by the stress F of the earth pressure, which increases downward, the wall body 22° 23 will be able to resist the stress F in advance.
Since the walls 22 and 23 are formed to be inclined at an angle θ corresponding to the angle of inclination, the walls 22 and 23 are finally corrected by the earth pressure and are formed in the vertical direction, which is the direction in which they are originally constructed. In addition, in the case where a pair of walls 22 and 23 are formed so as to face each other and the construction excavation part 25 is formed by excavating between the pair of walls 22 and 23, as described above, , a plurality of ribs 2 between mutually opposing wall bodies 22 and 23
4, it is possible to effectively prevent each wall body from being deformed during or after excavation due to the stress of earth pressure.

In the above embodiment, as a construction method for forming a wall in a groove formed by an excavator, the guide member to which the excavation chain is attached is made of a steel casing, and this guide member is left in the groove to form the wall. Although a construction method has been described, the process of forming a wall, which is a component of the present invention, is not limited to this construction method. As long as the first objective of the present invention and the effects described below can be achieved, such as the construction method of forming a wall, any method may be determined, and these changes do not change the gist of the present invention in any way. Needless to say.

〔Effect of the invention〕

As explained above in detail, the present invention forms a trench by excavating from the ground surface to underground with the excavating chain installed on the excavator tilted toward the excavator, and the groove is formed through a steel structure. Therefore, the wall body has an inclination angle corresponding to the inclination angle of the excavation chain. Therefore, the wall body is formed at an angle corrected from the ground surface to the originally intended angle due to stress caused by earth pressure.

Further, by forming at least one pair of walls formed at an angle in this way in a V-shape, and excavating a construction excavation part while interposing an arbitrary number of raised sides between the pair of walls, It is possible to effectively prevent the pair of walls from deforming or collapsing due to earth pressure during or after excavation of the construction excavation section, and it is also possible to sufficiently ensure the safety of workers.

[Brief explanation of drawings]

The drawings show one embodiment of the simple underground continuous wall construction method of the present invention. Fig. 1 is a side view schematically showing the inclined state of the trench formed by an excavator, and Fig. 2 is a side view schematically showing the inclined state of the trench formed by the excavator. FIG. 1---------One excavator 13---------Chain 21------One groove 22---One wall? 23------One other wall body 24------One side raising 25---111 Construction excavation part Fig. 1

Claims (2)

[Claims] (1) Tilt the excavation chain installed on the excavator toward the excavator, rotate the excavation chain in this inclined state, excavate from the ground surface to underground, and form a groove. A simple underground continuous wall construction method characterized by forming a wall through. (2) At least one pair of walls formed through a trench excavated by the construction method according to claim (1) are arranged in a V-shape on both sides of an excavated part for construction, and 1. A simple underground continuous wall construction method, characterized in that the construction is carried out by excavating the construction excavation part through an arbitrary number of raised walls between the walls of the construction.