JPH08193333A - Caisson press in method - Google Patents

Abstract

PURPOSE: To make it possible to reduce stress produced when a long span-caisson is pressed in and construct a large-scale underground structure by penetrating a caisson and pressing in the caisson while the load of the caisson is being placed on a permanent substructural column. CONSTITUTION: The lower end of a structural stud 4 of a central foundation pile 3 is fixed and erected. A caisson 5 is constructed on a ground and a permanent structural column 4 is adapted to penetrate into a through hole 51 where a jack 21 is fixed with the upper end of an earth anchor 2. The load of the caisson 5 is arranged to be placed on the permanent structural column 4 by way of a lowering device 6 of a mounting space 52 at the lower part of the through hole 51 of the caisson 5. Or when the caisson 5 is loaded on the lowering device 6, the jack is expandingly and contractingly lowered while the outside surface of the permanent structural column 4 is being fixed and opened alternately by means of a fixing device. When the jack is lowered, an underground story skeleton and an exterior wall are constructed with a tower crane 53. The portion of an underground skeleton layer 1 is excavated with an excavating machine 54 in a lower work chamber. Then, the earth anchor 2 is pulled up with the jack 21 so that the caisson 5 may be pressed in by the reaction. At that time, the settling speed of the caisson 5 is controlled with the lowering device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a caeson press-in method for constructing an underground structure by press-fitting caesons into the ground.

[0002]

2. Description of the Related Art One of the methods for constructing underground structures is
There is a press-in construction method of Son. This construction method is effective when it is desired to take as much underground as possible in a narrow place where both sides are sandwiched between buildings and the like.

[0003]

When constructing a large-scale underground structure by the press-in construction method, the length (span) in the horizontal direction of the caisson becomes large. Stress is generated. Therefore, it is necessary to enlarge the cross section of the caisson to counter such stress,
In reality, it is not possible to design such large-section caissons. Therefore, it is a reality that Cason's method of press-fitting cannot be adopted for the construction of large-scale underground structures.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and can reduce the stress at the time of press-fitting that occurs in a caisson having a long span, thus providing a large scale underground structure It is an object of the present invention to provide a causson press-fitting method that enables the construction of objects.

[0005]

That is, according to the present invention, in a caeson press-fitting construction method in which a caisson is press-fitted into the ground to construct an underground structure, the caisson is penetrated to establish a true column. The causon press-fitting method is characterized in that the caisson is press-fitted while the caisson's load is kept on the structure. In addition, in the cason press-fitting method in which a caisson is press-fitted into the ground to construct an underground structure, the caisson is pierced to raise the structure pillar, and the outer surface of this structure pillar has upper and lower ends. Equipped with a lowering device that alternately fixes the parts to the outer surface of the true column and expands and contracts while opening to support the caisson by this lowering device, and through the lowering device to the true column. It is characterized by press-fitting the caisson while entrusting the load of
It is a cason press-fitting method. Furthermore, in the cason press-fitting construction method in which a caisson is press-fitted into the ground to construct an underground structure, the caisson is pierced to set up a structure pillar, and the caisson through which this structure pillar penetrates. A nut is fixed to the peripheral portion on the bottom surface side of the through hole, the caisson is penetrated and screwed with the nut to mount a screw steel rod along the true column, and this screw steel rod is the case of the true column. -Connecting to a rotary drive device provided on the upper side of the son, rotating the screw steel rod to make it possible to lower the caisson integrally with the nut, and at the same time, to install the nut, the screw steel rod and the rotary drive device. It is characterized by press-fitting the caisson while depositing the caisson load on the structure column via
It is a cason press-fitting method.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. <a> Standing of true pillars As shown in Fig. 1, a water stop wall 1 is constructed around the planned construction site of the underground structure, and an earth anchor-2,
Build foundation piles 3 such as drill piles. The lower end of the foundation pile 3 is fixed to the center foundation pile 3 and the true post 4 is erected. Part of the ground is 1m
Drill to a degree. The required number of structural columns 4 is set up according to the construction scale.

<B> Construction of caisson Cason 5 is constructed on the ground. Through hole 5 in caisson 5
1 is opened, and the true pillar 4 is penetrated inside. Also,
A jack 21 such as a VSL jack is attached to the upper end of the earth anchor-2 and fixed to the upper surface of the caisson 5. In addition,
Generally, the underground structure is RC structure or SRC structure, but since the present invention can reduce stress, it can be S structure, and the construction period and the construction cost can be shortened.

<C> Descent Device As shown in FIGS. 1 and 4, a mounting space 52 is formed below the through hole 51 of the caisson 5, and the mounting space 52 is formed.
A descent device 6 is installed inside.

As an example of the descending device 6, a structure comprising a jack 61 which expands and contracts in the vertical direction and fixing devices 62a and 62b provided at the upper and lower ends thereof can be considered. Casson 5
Is mounted on the lowering device 6 and configured to bear the load on the true column 4 via the lowering device 6.

The descending of the caisson 5 is carried out by the fixing devices 62a, 6a.
The jacks 61 can be expanded and contracted while alternately fixing and opening the outer surface of the false column 4 by means of 2b, so that the jack 61 can be lowered like a worm. When the caisson 5 is press-fitted, the descending device 6 controls the sinking speed of the caisson 5 to
Can be performed so that excessive stress does not occur.

FIG. 5 shows a lowering device 7 having another structure. This lowering device 7 fixes a plurality of nuts 71 to the ceiling surface of the mounting space 52 of the caisson 5, penetrates the caisson 5, and screw-engages with the nuts 71 to form a plurality of threaded steel rods 72. Wear along the pillar 4. The threaded steel rod 72 is connected to the rotary drive motor 74 via a gear box 73 provided on the upper side of the casing 5 of the true column 4.

Therefore, it becomes possible to store the load of the caisson 5 on the true column 4 through the nut 71, the threaded steel rod 72 and the rotary drive device. The fall of Kason 5 is motor 74.
By rotating the threaded steel rod 72,
The caisson 5 can be lowered integrally with the nut 71.

<D> Cason press-fitting The tower crane 53 is installed on the caisson 5, and is used to construct a basement skeleton or outer wall. An excavator 54 such as an overhead traveling type is installed in the lower working room of the caisson 5,
As a result, excavation for one layer of the basement building is performed.

After the excavation is completed, as shown in FIG. 2, the jack 21 is used to pull up the earth anchor-2, and the caisson 5 is press-fitted by its reaction force. At this time, the descending device 6 controls the settlement speed of the caisson 5 so that an excessive stress is not generated in the caisson 5.

The above work is repeated to press-fit the caisson 5 to a predetermined depth, and then the main pile and the foundation pile 3 are joined as shown in FIG. The excavator 54 is removed and the lower working chamber of the caisson 5 is backfilled and the press-fitting is completed.

<E> Measurement of Cason Deflection The press-fitting of the caisson 5 is performed while measuring whether or not excessive stress deformation has occurred in the caisson 5. As one of the measuring methods, as shown in FIG. 6, a light emitter 8 is provided at one end of the bottom surface of the caisson 5 and a light receiver 8 is provided at the middle and the other end thereof.
A method in which 1, 82 are equipped and the amount of displacement thereof is measured can be considered.

Further, the pressure of the press-fitting jack 21 and the jack 61 of the lowering device 6 is measured, and a measuring gauge such as a strain gauge is attached to the reinforcing bar in the caisson 5 to measure the depression and the sinking. There is also.

[0018]

Since the present invention has been described above, the following effects can be obtained. <a> Since the caisson is press-fitted into the true column while supporting it, even if the cason has a large span, the span is substantially divided by the true column, and It is possible to reduce the stress generated in the. Therefore,
Large-scale underground structures can be constructed using the Son press-fitting method.

<B> Since the mountain retaining wall is unnecessary, it is possible to shorten the construction period and the construction cost.

<C> In the present invention, since the stress can be reduced, the caisson can be made into an S structure, and the construction period and the construction cost can be shortened.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing the process of starting a structure pillar and constructing the bottom floor caisson.

FIG. 2 is an explanatory diagram of a caulking press-fitting process.

FIG. 3 is an explanatory diagram showing a state in which caulking has been press-fitted.

FIG. 4 is an explanatory view of a causson lowering device.

FIG. 5 is an explanatory view of a causson descending device.

FIG. 6 is an explanatory diagram of a method for measuring the deflection of a caisson.

Continuation of the front page (72) Inventor Eiji Tajima 1-25-1 Nishishinjuku, Shinjuku-ku, Tokyo Taisei Corporation

Claims (3)

[Claims] 1. A caeson press-fitting method for press-fitting a caisson into the ground to construct an underground structure, in which a caisson is pierced to raise a structure pillar, and the causson is attached to the structure pillar. The causson press-fitting method is characterized in that the caisson is press-fitted while the load of 2. A caisson press-fitting method for constructing an underground structure by press-fitting a caisson into the ground to raise a structure pillar by penetrating the caisson, and on the outer surface of this structure pillar. Equipped with a lowering device that alternately fixes the upper and lower ends to the outer surface of the true column, expands and contracts while opening, and supports the caisson by this lowering device and attaches to the true column via the lowering device. A causson press-fitting method characterized in that the caisson is press-fitted while the caisson load is kept. 3. A cason press-fitting method of constructing an underground structure by press-fitting a caisson into the ground, initiating a true pillar by penetrating the caisson and passing through the true pillar. -A nut is fixed to the peripheral edge of the bottom of the through hole of the son, the caisson is penetrated and screwed with the nut, and a threaded steel rod is mounted along the structure column. It is connected to a rotation driving device provided above the caisson of the pillar, and the caisson can be lowered integrally with the nut by rotating the screw steel rod, and the nut, the screw steel rod and the rotation The caisson press-fitting method is characterized in that the caisson is press-fitted while the caisson load is entrusted to the true column via a drive device.