JPH0246758B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <<Industrial Application Field>> The present invention relates to a method for efficiently, reliably, and economically treating excavated soil containing muddy water generated in a muddy water construction method.

<<Conventional technology and its problems>> In the muddy water construction method, the ground is excavated while filling an underground trench hole with muddy water as a stabilizing liquid.During the excavation, excavated soil containing muddy water is generated. The water content of the excavated soil varies depending on the soil quality, but it is usually
It is as high as 25-70% and exhibits properties that are above the liquid limit.

Therefore, when the excavated soil is loaded directly into a dump truck and transported to a dumping site, it spills all over the place during transportation, which not only requires a large amount of money to dispose of, but also becomes a source of pollution.

Therefore, in the past, excavated soil was stored in a temporary storage area on the site, dried in the sun to lower the water content, and then transported to a dumping site, or when a temporary storage area could not be secured, container trucks were used unavoidably. Countermeasures have been taken, such as transporting the waste in small quantities using dump trucks or other vehicles equipped with measures to prevent muddy water from seeping out.

However, the former method has the problem that it takes too many days to lower the excavated soil to a predetermined moisture content. In addition, the latter may not meet the acceptance standards of soil dumping sites due to the poor transport efficiency of excavated soil and the high water content of excavated soil. Since muddy water that can be reused as a stabilizing liquid is also discarded, there are problems such as being uneconomical.

The present invention solves the above problem by focusing on the fact that muddy water floats to the top due to vibrations during the process of transporting excavated soil with a high water content using a dump truck or the like. To provide a treatment method that uses a soil tank equipped with a drain pipe and a decompression drain pipe to collect muddy water in excavated soil for reuse, and improves the efficiency of transporting excavated soil with a reduced water content ratio. This is the purpose.

<Means for Solving the Problems> In order to achieve the above object, in the method for treating excavated soil in the muddy water construction method of the present invention, a plurality of vibrating devices are installed inside the excavated soil containing muddy water generated in the muddy water process. The excavated soil is vibrated by driving the vibrating device, and is housed in an earthen tank in which a decompression drain pipe is installed between these vibrating devices and has a through hole that allows the mud to pass through. The method is characterized in that muddy water separated from the excavated soil is extracted into the reduced pressure drain pipe through the hole.

《Function》 According to the method for treating excavated soil having the above configuration, vibration is applied to the excavated residual soil containing muddy water using a vibrating device, so that the separation of the earth and sand of the excavated soil and the muddy water is promoted, and the muddy water separated from the residual soil is It is drawn into the depressurized drain pipe through the through hole and quickly extracted from the excavated soil.

<<Examples>> Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

The figure shows an example of the method for treating excavated soil according to the present invention.

The treatment method shown in the figure is applied when forming an underground excavation trench 1 using the muddy water construction method. Since excavation is carried out while filling the hole 1 with muddy water 2, excavation residue 5 containing muddy water 2' is generated as a result of the excavation.

Therefore, in the present invention, the excavated soil 5 is processed according to the following procedure.

The excavated soil 5 is pumped from the trench 1 into the soil tank 3.
moved inward.

A pair of vibrating devices 4, 4 are mounted on the inner side surface of the soil tank 3, facing each other, and the vibrating devices 4,
A hollow cylindrical drain pipe 9 with a large number of through holes bored between the drain pipes 9 is installed.

One end of the drain pipe 9 is extended to the outside of the soil tank 3 and connected to the upper part of the mud storage tank 11.

A pressure reducing device 10 is disposed in the upper part of the mud storage tank 11, and a mud feeding path extending to the groove hole 1 is installed in the lower part of the mud storage tank 11. The pressure inside the drain pipe 9 decreases.

When the excavated soil 5 is stored in the soil tank 3, the vibration device 4 and the pressure reducing device 10 are driven.

As a result, vibration from the vibration device 4 is applied to the excavated soil 5, and separation of muddy water 2' and earth and sand in the excavated soil 5 is promoted.

As for the vibration conditions in this case, vertical vibration is effective, but lateral vibration may also be used, the frequency is 1500 to 7000 VPM, and the vibration time is 1 to 7000 VPM.
3 minutes is desirable, and is selected as appropriate depending on the condition of the excavated remaining soil 5.

The separated muddy water 2' is sucked through the hole in the drain pipe 9, extracted into the mud storage tank 11, and then reused as a stabilizing liquid when excavating other trenches via the mud feeding route. be done.

In this case, since the drain pipe 9 is vibrated by the vibration device 4, clogging of the through hole through which the muddy water 2' passes is prevented.

On the other hand, the excavated soil 5 from which the muddy water 2' has been separated is transported by a dump truck or the like and disposed of as a landfill in a soil dumping site, since its water content is significantly reduced.

Now, when the excavated residual soil 5 is processed in the above procedure, the separation of the muddy water 2' is promoted by applying vibration to the excavated residual soil 5, and the separated muddy water 2'
Since the water is extracted by suction by reducing the pressure inside the drain pipe 9, the water content ratio of the excavated soil 5 can be reduced in a short time.

<<Effects of the Invention>> As explained in detail above, according to the method for treating excavated soil in the muddy water construction method according to the present invention,
The water content ratio of excavated soil can be reduced in a short time, and the muddy water extracted from excavated soil can be reused as a stabilizing liquid.

In addition, since the water content of excavated soil is decreasing,
Efficiency in disposing of this will be improved and disposal costs will also be reduced.

[Brief explanation of the drawing]

The figure is a schematic vertical sectional view showing an embodiment of the method of the present invention. 1...Underground excavated trench hole, 2,2'...Muddy water, 3...
...Earth tank, 4...Vibration device, 5...Excavation remaining soil, 9...
...Drain pipe, 10...Pressure reducing device, 11...
mud storage tank.

Claims (1)

[Claims] 1 Excavated soil containing muddy water generated by muddy water construction method,
It is housed in an earthen tank equipped with a plurality of vibrating devices and a depressurized drain pipe with a through hole for passing the muddy water between these vibrating devices.The vibrating devices drive the excavated soil. A method for treating excavated soil in a muddy water construction method, characterized by applying vibration and extracting muddy water separated from the excavated soil into the depressurized drain pipe through the through hole.