JP3292801B2 - Ground improvement method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is to improve soft ground, ground which is liable to be liquefied by an earthquake, etc., and to improve the ground for correcting the level of an underground object or a ground structure, correcting a sunk road, and the like. Ri engages the ground improvement method, in particular, engineering which can improve inexpensively ground by effectively utilizing the waste incineration ash
About the law.

[0002]

2. Description of the Related Art Conventionally, as a method of correcting the movement of an underground buried object without digging, a ground coagulant (grout) is intensively injected into the ground opposite to the direction in which the object is to be moved, and the pressure is applied. There is a method of moving and correcting underground buried objects, and we also propose an improved method (for example, Japanese Patent Laid-Open No. 1-41).
776 etc.).

[0003]

However, in the conventional method, a mixture of water glass, cement, water and the like is used as a coagulant to be injected, so that the material becomes expensive, and It was extremely difficult to calculate and control the injection amount due to mixing and fluidity. In addition, since the groundwater and the soft soil are pushed out of the construction area, there is a possibility that other buried objects and structures may be affected, and the management is extremely difficult.

On the other hand, an approximation is that a large amount of sludge and garbage is generated as industrial waste and household waste, and these are incinerated. However, these incinerated ash are used only for a small part. At present, most of them are dumped at high cost.

Therefore, an object of the present invention is to easily control the injection amount of a hardening agent to be injected into the ground and to perform the operation easily, and to carry out the operation at a low cost by utilizing waste incineration ash. It is an object of the present invention to provide a ground improvement method capable of improving the ground.

[0006]

In order to achieve the above object, the soil improvement method of the present invention is to vertically lay a pipe in the ground where the ground is to be improved, and to apply a soil improving agent through the pipe. In the ground improvement method to be injected, a press-fit pipe is buried in the ground by a press-fit pipe installation machine, and as the ground improver, a hardening agent mainly composed of ordinary Portland cement and an aggregate mainly composed of waste incineration ash. To obtain a powder obtained by mixing
After the granular material is pressed into the ground from the press-fitting pipe by the granular material injection pump, water around the pressed granular material is absorbed and hardened, and the granular material is pressed into the deepest part. Then, the press-fitting pipe is pulled up by a predetermined amount in the vertical direction, and the granular material is pressed again. In this manner, the pulling-up of the press-fitting pipe and the press-fitting of the granular material are repeatedly carried out, and a plurality of locations are provided at predetermined intervals in the horizontal direction. This is a construction method that is carried out at an intermediate point after construction.

In this case, a mortar is filled in a boring hole formed by extracting a press-fitting pipe after press-fitting the granular material.

[0008] The ground improvement apparatus for implementing the present invention includes :
Press-fitting pipes to be built in the ground where the ground is to be improved, press-fitting pipe installation machines for press-fitting the press-fitting pipes into the ground, and hardening agents mainly made of Portland cement and waste incineration ash as main materials A tank vehicle for transporting powder and granules obtained by mixing the aggregate to a construction site, a construction vehicle equipped with a pressure pump for supplying the powder and granules taken out from the tank vehicle to the press-fit pipe, and the press-fit pipe It is mounted on the installation unit, and a granular material pressurizing pump for pressing the supplied granular material into the ground press-fit tube.

At the time of construction, a press-fitting pipe is erected vertically in the ground by a press-fitting pipe installation machine, and the powdery material is transported to a construction site by a tank vehicle. From the powder and supply to the press-fit pipe,
The granular material supplied to the press-fitting pipe is pressed into the ground by a granular material press-fitting pump mounted on a press-fitting pipe installation machine.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a ground improvement method according to the present invention will be described with reference to the drawings together with its apparatus.
System diagram showing an example of the construction stage for consolidation settlement prevention of crosslinking and the road mounting portion, FIG. 2 is a schematic diagram showing a field device, FIG. 3 is a sectional view of a main part showing a granular material pressed construction process. As shown in FIG. 1, the mounting portion 23 connecting the bridge portion 21 and the road 22 often consolidates and sinks. Even if the mounting portion 23 is embanked and repaired, it quickly sinks. Part 23
It is necessary to rehabilitate the ground after renovating the ground.

In the ground improvement in such a case, first, the hardening agent mainly containing ordinary Portland cement stored in the hardening agent storage tank 1A and the waste incineration ash stored in the aggregate storage tank 1B are used. Aggregate as a main material is mixed by the mixing device 3 while being controlled by the flow control device 2 to obtain powder and granules.

Next, the press-fitting pipe 5 is erected vertically by the press-fitting pipe setting machine 4 in the ground of the mounting portion 23, and the granular material is transported to the site by the tank vehicle 6, and is mounted on the construction vehicle 7. The granular material is supplied to the press-fitting pipe 5 by a pressure pump 8. The granular material supplied to the press-fitting pipe 5 is pressed into the ground by a granular material press-fitting pump 9 mounted on the press-fitting pipe setting machine 4.

As shown in FIGS. 1 and 3, after a predetermined amount of the granular material CP is press-fitted into the deepest portion, the press-fitting pipe 5 is pulled up by a predetermined amount in the vertical direction and press-fitted again. And press-fitting of the granular material CP are repeated, and finally, the press-fitting pipe 5 is withdrawn and the boring hole H formed by this is removed.
Is filled with mortar M.

As described above, construction is performed at the next place at a predetermined interval in the horizontal direction. However, the soft ground is often spread over a wide area, and it is necessary to construct at a large number of places because the construction place is large. After installing at intervals, work is performed in the middle.

As the hardening agent, usually Portland cement is used as a main material, and a little powdered lime or the like may be mixed with this. Further, as an aggregate, waste incineration ash such as garbage and sludge is used as a main material, and a small amount of fine sand, fine slag, pearlite, or the like may be mixed with this.

In the system diagram of FIG. 1, it is shown that the granules are directly injected into the press-fitting pipe 5 from the mixing device 3 via the granule injection pump 9, but for reasons such as road traffic obstruction. , Because the entire device cannot be installed on site,
As shown in FIG. 2, the granular material obtained by the mixing device 3 is transported to a site by a tank vehicle 6, and the granular material CP is sucked from a tank of the tank vehicle 6 by a pressure pump 8 of a construction vehicle 7. And supplied to the press-fitting pipe 5 through the pressure-feeding hose 10.

In FIG. 1, reference numeral 11 denotes a compressor for the hardening agent storage tank 1A and an aggregate storage tank 1B.
Is a hardening agent pump, 13 is an aggregate pump, and 14 is a water tank 15 that absorbs water that may be used for drilling on an asphalt road or cleaning the road when boring with the press-fitting pipe setting machine 4. Is a water pump. In FIG. 2, reference numeral 16 denotes a generator mounted on the construction vehicle 7;
7 is a flow dividing device, 18 is a hydraulic pressure generator for the press-fitting pump mounted on the press-fitting pipe setting machine 4, and 19 is a hydraulic hose.

[0018]

As shown in the procedure (a) of FIG. 3, the press-fitting pipe installation machine 4 basically pierces the underground to be constructed without water, and press-fits the press-fitting pipe 5 to a predetermined depth. Tank vehicle 6
The powder and granules conveyed in the above are pressure-fed to the press-fitting pipe 5 via the flow dividing device 7 and the pressure-feeding hose 10 by the pressure pump 8 of the construction vehicle 7,
As shown in step (b), the powder is injected into the ground by the powder injection pump 9.

The press-fitted granular material CP absorbs moisture around it and is hardened, thereby consolidating the soil. Step (c),
As shown in (d), when a predetermined amount of press-fitting is performed, the press-fitting pipe 5 is inserted.
Pull up a little in the vertical direction and press-fit a predetermined amount at that position.
In this manner, the press-fitting operation is repeated in a stepwise manner. As shown in step (e), after the press-fitting is completed, the press-fitting pipe 5 is extracted, and the resulting bore hole H is filled with mortar M. In order to concentrate on a wide construction site, as shown in step (e), every other line is constructed in the horizontal direction, and then the intermediate part is constructed.

As described above, the press-fitted granular material CP absorbs the surrounding water and hardens, so that soil compaction occurs.
This can be improved even in a flexible ground in a wide range. In addition, since water is absorbed without moving groundwater, there is no adverse effect outside the area.

[0021]

According to the ground improvement method of the present invention, a press-fit pipe is erected vertically in the ground by a press-fit pipe installation machine,
A granule obtained by mixing a hardening agent mainly composed of ordinary Portland cement and an aggregate mainly composed of waste incineration ash is pressed into the ground from the press-in pipe by a powder injection pump. This is a method of absorbing and hardening the water around the pressed-in powder and granular material, so that it can be reliably improved even on soft ground with a lot of moisture, repairing the road surface and moving underground objects The ground can be hardened at the time of correction or the like, and the ground can be easily improved even if the ground is liquefied due to an earthquake or the like. Further, after the granular material is pressed into the deepest portion, the press-fitting pipe is pulled up by a predetermined amount in the vertical direction and the granular material is pressed again, and by repeating the pulling-up of the press-fitting pipe and the press-fitting of the granular material in this manner, The ground can be improved from the deepest part to the upper part in the ground, and the ground can be entirely improved even if the soft ground is wide.

Since the hardening agent to be injected into the ground is a granular material, it is easy to control the injection amount and the like, and can be easily applied. In addition, it can be implemented at low cost by using waste incineration ash. .

[Brief description of the drawings]

[1] shows the actual施例of ground improvement construction method according to the present invention, system diagram showing an example of construction in order to prevent consolidation settlement of the cross road mounting portion.

FIG. 2 is a schematic diagram showing a field device.

FIG. 3 is a cross-sectional view of a main part showing a procedure for press-fitting a granular material.

[Explanation of symbols]

 Reference Signs List 1A Hardening agent storage tank 1B Aggregate storage tank 2 Flow control device 3 Mixing device 4 Press-fitting pipe installation machine 5 Press-fitting pipe 6 Tank vehicle 7 Construction vehicle 8 Pumping pump 9 Powder pressurizing pump 10 Pressing hose CP Powder H Boring hole M Mortar filling

Claims (2)

(57) [Claims] 1. A ground improvement method in which a pipe is erected vertically in the ground where ground is to be improved and a ground improvement agent is injected through the pipe. The ground improver is obtained by mixing a hardening agent mainly composed of ordinary Portland cement and an aggregate mainly composed of waste incineration ash as the ground improving agent, thereby obtaining a powdery and granular material. After the body is pressed into the ground from the press-fitting pipe by the powder press, the water around the pressed-in powder is absorbed and hardened, and the powder is pressed into the deepest part. The vertical
And then press-fit the granules again and press-fitting the press-fit pipe and press-fitting the granules are repeatedly performed at a predetermined interval in the horizontal direction. A ground improvement method characterized by construction at an intermediate location. 2. The soil improvement method according to claim 1, wherein a mortar is filled in a boring hole formed by extracting a press-fitting pipe after the powder and granular material is press-fitted.