JP2002047644A - Work execution controlling method for existing cutoff plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work execution controlling method for an existing cutoff plate allowing objectively judging whether the execution of the existing cutoff plate is normal or not by a simple method in a method for constructing an underground cutoff wall by penetrating a succeeding cutoff plate into the existing cutoff plate penetrated in an underground vertical direction, engaging the succeeding cutoff plate to the existing cutoff plate. SOLUTION: In the method for constructing the underground cutoff plate by providing each one of a male engagement part and a female engagement part on both side parts of a vertical direction of the cutoff plate and penetrating a succeeding cutoff plate into the existing cutoff plate penetrated in the underground vertical direction, engaging the male engagement part and the female engagement part adjacent each other, this method is the execution controlling method for the existing cutoff plate for judging whether the execution of the existing cutoff plate is normal or not by installing a load cell for measuring load applied in a lower direction of the cutoff plate at a ground surface portion on an upper side of the existing cutoff plate and time-sequentially measuring the load, when the succeeding cutoff plate is engaged to the existing cutoff plate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction management method for an existing barrier plate for judging whether or not the construction of the existing barrier plate is normal in an underground barrier plate construction method for water stoppage. .

[0002]

2. Description of the Related Art Conventionally, for the purpose of preventing the spread of underground pollution due to waste, and containing regulating ponds and river embankments,
When constructing an underground blocking wall, a method is generally employed in which a blocking plate such as a sheet pile or a water blocking board having an appropriate width is sequentially connected in the width direction under the ground.

[0003] The shielding plate is mainly made of a steel plate or a sheet made of a flexible synthetic resin which exhibits rigidity even if the thickness is small. For example, as shown in FIG. ~
1.5 m, sheet main body 11 having an effective length of which plate length H varies depending on the driving depth, lower gripping margin 16 when set on the penetrating frame, and engaging portions at both ends engaging with the adjacent blocking plate A barrier plate 10a, 10b having two or three is known.

[0004] Penetration of the blocking plate into the ground is performed by using a penetration frame, and the lower end of the female engaging portion of the blocking plate is engaged with the male engagement of the blocking plate already buried in the ground vertically. Entrained in the ground while engaging the part. In this case, the lower end of the female engaging portion is easily deformed due to the resistance of the ground, and due to this deformation, the male engaging portion and the female engaging portion are not smoothly engaged. There is a possibility that the subsequent blocking plate may penetrate into the ground without engaging, without being engaged. On the other hand, the engagement between the male engaging portion and the female engaging portion is not performed smoothly,
If a forcible penetration of the succeeding barrier plate is performed with high resistance, breakage occurs in the sheet body of the existing barrier plate, causing a serious problem that a desired water stopping function cannot be achieved.

As a method for determining whether the engagement state between the male engaging portion and the female engaging portion is normal, JP-A-2000-13
No. 6529 discloses that when a subsequent impermeable sheet is engaged with an existing impermeable sheet, a small preceding piece is previously engaged with the existing impermeable sheet, and the subsequent impermeable sheet is penetrated. A method for determining whether or not the engagement state of the following impermeable sheet with the existing impermeable sheet is normal by measuring the movement amount of the preceding piece that is pushed and lowered along the existing impermeable sheet. Is disclosed. Although this method is a useful technique in that it is possible to easily determine whether or not the engagement state between the male engagement section and the female engagement section is normal, the method may be applied to the existing blocking plate, for example, if the seat body is damaged. Such a situation cannot be detected. On the other hand, the breakage of the sheet body of the existing blocking plate may be caused by not only the forced penetration caused by the above-described engagement failure, but also the collapse of the earth and sand around the existing blocking plate even in the normal engagement state. Damage and tear may occur due to mechanical shock. Therefore, if the breakage phenomenon of the existing blocking plate, which is caused by such various causes, that is, the construction failure can be detected, it is advantageous in that the penetration and the like can be redone and the construction can be performed with high reliability.

[0006]

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a method for connecting a subsequent blocking plate to a male engaging portion and a female engaging portion adjacent to each other with respect to an existing blocking plate penetrating vertically in the ground. In a method of penetrating while engaging and constructing an underground barrier,
An object of the present invention is to provide a construction management method capable of objectively determining whether the construction of an existing blocking plate is normal or not by a simple method.

[0007]

Under such circumstances, the present inventors have conducted intensive studies and as a result, when engaging the subsequent blocking plate with the existing blocking plate, the ground surface portion above the existing blocking plate has been found. If a load cell for measuring the load in the downward direction of the blocking plate is installed and the load applied to the load cell is measured with the passage of time (penetration depth), for example, tears generated in the seat body due to an accidental factor Have been found that can be more objectively determined, and the present invention has been completed.

That is, the present invention (1) has one of a male engaging portion and a female engaging portion on both sides in the vertical direction of the blocking plate, respectively. In a method of penetrating a subsequent blocking plate while engaging a male engaging portion and a female engaging portion adjacent to each other, and constructing an underground blocking wall,
When the subsequent barrier plate is engaged with the existing barrier plate, a load cell for measuring a load in a downward direction of the barrier plate is installed at a surface portion above the existing barrier plate, and the load is time-sequenced. An object of the present invention is to provide a construction management method for an existing barrier plate, which determines whether or not the construction of the existing barrier plate is normal by performing a measurement. By adopting such a configuration, for example, when the load applied to the load cell gradually increases with time, it can be understood that the existing blocking plate is in a normal construction state. Also, if the load suddenly rises from this normal construction state and then falls instantaneously, any external force shock such as collapse of the surrounding earth and sand will cause a break in the sheet body part of the existing barrier plate, resulting in poor construction. It turns out that it is. Furthermore, when the load gradually rises from the normal construction state and then falls instantaneously, when the subsequent barrier plate is forcibly penetrated due to an engagement failure, the sheet body portion of the existing barrier plate is torn and the construction is performed. It turns out that it is bad. As described above, by reading the load curve of the existing barrier plate, the construction state of the existing barrier plate can be more objectively determined.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A construction management method for an existing blocking plate according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a diagram for explaining a construction management method for an existing barrier plate in the present embodiment, FIG. 2 is a view taken along line AA in FIG. 1, and FIG. 3 is a load cell load obtained by the construction management method. The two forms (A) and (B) are shown by curves.

A known method is applied to the construction method of the underground barrier wall to which the construction control method of the existing barrier plate of the present invention is applied. Specifically, first, a plurality of underground blocking plates 10a, 10b
・ ・ Is prepared. The underground blocking plates 10a and 10b have the same shape, and are formed of a flexible synthetic resin obtained by welding one of the engaging male member 2 and the engaging female member 3 to both longitudinal sides of the seat body 1. It is a shielding plate made of. Engaging male member 2
Is composed of a male engaging portion 4 and a base 5 integrated with the male engaging portion 4 and welded to the seat body 1. The engaging female member 3 includes a female engaging portion 8 and a base 7 integrated with the female engaging portion 8 and welded to the seat body 1. The male engaging portion 4 and the female engaging portion 8 have a structure capable of engaging with each other (FIG. 2).

The penetration of the blocking plate 10a is performed by penetrating into the ground together with a rigid penetration frame (not shown) by a penetration machine, penetrating to a predetermined depth, and then raising the penetration frame while leaving the blocking plate. . Next, the existing blocking plate 10a
A load cell 9 for measuring a load hanging in a downward direction of the existing blocking plate 10a is installed on the ground surface portion 101 above the above. The method of installing the load cell 9 is not particularly limited, and a method of measuring the strain of the wire 102 that suspends the existing blocking plate 10a in a tension state as shown in FIG. 1 can be used. The data of the load measured by the load cell 9 is sent to the arithmetic processing unit 12. The arithmetic processing unit 12 includes a recording unit, and processes the depth of the underground of the penetration blocking plate 10b in a time-series manner with respect to the amount of strain (load) sent from the load cell 9, and displays this in an oscilloscope at the recording unit, for example. Or something.

Next, the blocking plate 10b is penetrated in the same manner. The penetration of the blocking plate 10b
Of the female engaging portion 8 is engaged with the male engaging portion of the blocking plate 10a which has already penetrated in the vertical direction underground, and the string-shaped sealing material 13 is engaged with the female engaging portion at the tip of the male engaging portion. Perform while distributing in the joint. In this case, the load cell 9 and the arithmetic processing unit 1
2 is turned on.

The blocking plate 10b penetrates into the lower end of the female engaging portion while receiving the resistance of the ground. This input is
It extends to the adjacent existing blocking plate 10a via the engaging portion. Therefore, the adjacent existing blocking plate 10a receives a pulling force in the downward direction. The downward pulling force (load) of the existing blocking plate 10a can be detected by a load cell installed on the ground surface above the existing blocking plate 10a. At the time of underground penetration, if the engagement between the female engaging portion of the penetration blocking plate 10b and the male engaging portion of the existing blocking plate 10a is normal, a load curve showing a temporal change of a load hanging downward of the existing blocking plate 10a. Is a straight line having a constant slope shown as "normal load" in FIG. When such a load curve is obtained, it can be said that the existing blocking plate 10a is in a normal construction state.

On the other hand, as another form of penetration, the blocking plate 10
FIG. 3 shows a load curve showing a temporal change of the pulling force hanging downward of the existing blocking plate 10a when the b is penetrated into the ground.
In some cases, the curve (solid line) of (A) is shown. That is, it increased from a normal installation state (a normal load state) the load is suddenly, after a peak value p _1, a case where the minimum value p ₂ is lowered instantaneously. This is because a sudden downward pulling force acts on the existing blocking plate 10a due to some external shock such as the collapse of the surrounding earth and sand, and the maximum load p ₁
This pulling force causes the tear 6 of the seat body 1, and the tearing lowers the downward pulling force acting on the existing blocking plate 10 a, and the minimum load p
₂ is shown. Therefore, in this case,
The existing blocking plate 10a is determined to be improper in construction and is repaired. Specifically, the penetration is stopped, the power of the load cell 9 and the arithmetic processing unit 12 is turned off, and these are removed from the existing blocking plate 10a, and the penetration blocking plate 10b and the existing blocking plate 1 are removed.
Raise 0a. Then, the shielding plate 10a is replaced with a new one, and the same penetration work as described above is performed again.

Further, as another form of penetration, a load curve showing a temporal change of a load hanging downward of the existing blocking plate 10a may be a curve (solid line) of FIG. 3B.
That is, increases gradually the load from the normal construction conditions (normal load state), a peak value p _3, then lowered instantaneously, a case where the minimum value p _4. This is because the penetrating blocking plate 10b is forcibly penetrated in a situation caused by the engagement failure between the male engaging portion of the existing blocking plate 10a and the female engaging portion of the penetrating blocking plate 10b, and the existing blocking plate 10a gradually becomes stronger downward. It is considered that the pulling force was applied, and finally the sheet body 1 of the existing blocking plate 10a was torn. In this case, it is determined that the existing blocking plate 10a is improperly constructed, and the penetration is stopped and the repair work is performed as described above.
In this re-penetration process, it is important to take measures such as removing the soil near the engaging portion so as to prevent the male engaging portion and the female engaging portion from becoming defective in engagement.

FIG. 2 shows the form of engagement between the engaging portion of the blocking plate 10a and the blocking plate 10b obtained under the above-described normal construction conditions. The engagement is ensured, and a structure is employed in which a water-swellable sealing material 13 is interposed in the engagement gap to maintain high watertightness.

[0017]

According to the present invention, for example, when the load applied to the load cell gradually increases with time, it is in a normal construction state. Further, when the load suddenly rises from this normal construction state and then falls instantaneously, it indicates that the sheet body has been torn by some external shock such as collapse of the surrounding earth and sand. Furthermore, if the load gradually rises from this normal construction state and then falls instantaneously, if the male engaging portion of the existing blocking plate and the female engaging portion of the penetrating blocking plate are not properly engaged, the subsequent blocking plate may be damaged. Indicates that the sheet body was torn by the forcible penetration of the sheet. In this way, by reading the load curve of the load cell, it is possible to more objectively determine the construction state of the existing blocking plate. Also,
According to such a construction management method of the existing blocking plate, an abnormal situation can be detected during the penetration process, so that the repair operation can be performed quickly. In addition, if an arithmetic processing unit is connected to the load cell, the penetrating construction history of each used blocking plate can be recorded and stored in the recording unit. Also, if you can get a lot of intrusion history data,
By analyzing this, the cause of the construction failure can be determined with high accuracy from the load curve.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a construction management method of an existing blocking plate according to the present embodiment.

FIG. 2 is a view taken along the line AA of FIG. 1;

FIG. 3 shows two types of load curves (A) and (B) of a load cell obtained by the construction management method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Seat main body part 2 Engagement male member 3 Engagement female member 4 Male engagement part 5 Base (male side) 6 Torn (damaged part) 7 Base (female side) 8 Female engagement part 9 Load cell 10a, 10b Underground cutoff Board 13 Water-swellable sealing material 16 Grip margin 101 Ground surface 102 Suspension wire

Claims (1)

[Claims] 1. A shield plate having one of a male engaging portion and a female engaging portion on both sides in the vertical direction of a shielding plate, and a succeeding shielding plate is attached to an existing shielding plate penetrating vertically in the ground. In a method of constructing an underground blocking wall by engaging and penetrating an adjacent male engaging portion and a female engaging portion, when the subsequent blocking plate is engaged with the existing blocking plate, the existing blocking A load cell for measuring the load in the downward direction of the barrier plate is installed on the ground surface above the board, and it is determined whether the construction of the existing barrier plate is normal by measuring the load in time series. Characteristic construction management method of existing barrier plate.