JP6484523B2 - Construction method of permeable purifier and groundwater sampling structure - Google Patents

Description

  The present invention relates to a method for constructing a permeable purifier and a groundwater collection structure.

  There are known permeable purifiers that purify groundwater contamination in situ. As a groundwater sampling structure for confirming the effect of this type of permeable purification body, a structure in which a pipe material such as a perforated pipe is installed inside the purification body is generally used (for example, Patent Document 1).

JP 2007-283230 A

  When the pipe material is installed in the permeable purification body, it is necessary to input the purification material after arranging the pipe material, so that the position of the pipe material may be largely deviated from the planned position. If the position of the tube material is shifted, it becomes impossible to collect water from the planned position, and thus there is a possibility that the effect of the permeable purifier cannot be accurately grasped.

  From such a viewpoint, it is an object of the present invention to provide a method for constructing a permeable purification body in which a pipe disposed in the permeable purification body does not easily move. It is an object to provide a groundwater sampling structure that can be grasped.

The invention according to claim 1 for solving such a problem includes an excavation process for forming a shaft in the ground containing contaminated groundwater, and a purification material for purifying the contaminated groundwater is filled in the shaft, and for collecting groundwater And a filling step of installing the support member holding the lower end portion of the tube material in the shaft. The support member includes a ring-shaped outer frame portion disposed along an inner peripheral wall of the shaft, a rod-shaped support portion that extends from the outer frame portion toward the central portion of the shaft, and a rod-shaped support portion that rises from the outer frame portion. A first step of filling the purification material up to an installation height of the outer frame portion and the support portion , and a lower end portion of the tube material fixed to the support portion, A second step of placing the outer frame portion and the support portion on the upper surface of the purification material filled in the first step; and a third step of filling the purification material on the outer frame portion and the support portion . Steps.

  In such a method for constructing a permeable purifier, since the pipe for collecting groundwater is positioned using the support member, the position of the pipe does not easily shift when the purifier is filled.

The invention according to claim 2 includes a support member embedded in a permeable purification body filled in a shaft, and a pipe for collecting groundwater from the inside of the permeable purification body to the upper end portion of the permeable purification body. It is a groundwater sampling structure. A water sampling port for taking in groundwater in the permeable purification body into the tube material is formed at the lower end portion of the tube material, and the lower end portion of the tube material is held by the support member.

  According to such a groundwater sampling structure, since the lower end portion of the pipe material is held by the support member, the water sampling port provided at the lower end portion of the pipe material can be installed at a predetermined water sampling position. That is, according to the groundwater sampling structure according to the present invention, it is possible to install the pipe sampling port at a planned position, and thus it is possible to accurately grasp the effect of the permeable purifier.

In the invention which concerns on Claim 2 , the said support member is a ring-shaped outer frame part arrange | positioned along the inner peripheral wall of the said vertical shaft, and the some rod-shaped support part which goes to the center part of the said vertical shaft from the said outer frame part And a rod-shaped guide part rising from the outer frame part , the tube material is held by the guide part, and the lower end part of the tube material is fixed to the support part,

If it does in this way, since the outer frame part of a support member will be positioned along the inner peripheral wall of a shaft, it will become difficult to move support member itself, and the installation precision of a water sampling port will improve by extension.
Moreover, since a pipe material can be arrange | positioned along the inner peripheral wall of a shaft, a pipe material does not become obstructive when throwing a purification material into a shaft.

In the invention which concerns on Claim 3, when the said support part arrange | positioned in the upstream of the said water sampling inlet is based on the flow of groundwater among the said several support parts, it is in the direction which cross | intersects the flow direction of groundwater. Are arranged along.

  In this way, even if a water channel is formed along the support located on the upstream side of the water sampling port, the water that has passed through the water channel does not flow directly into the water sampling port. It becomes difficult for unpurified water to mix in the water that is used.

In the invention which concerns on Claim 4 , the said guide part and the said pipe material are arrange | positioned along the inner peripheral wall of the said shaft in the downstream of the flow of groundwater, The lower part of the said pipe material is bent, The said water sampling port is, It is arranged at the center of the shaft.

According to the construction method of the permeable purifier according to the present invention, the position of the pipe material disposed in the purifier is difficult to shift.
Moreover, according to the groundwater sampling structure according to the present invention, it is possible to accurately grasp the effect of the permeable purifier.

It is a perspective view which shows typically the purification | cleaning wall containing a permeable purification body. It is a partially broken perspective view of a permeable purifier including a groundwater sampling structure according to an embodiment of the present invention. It is a perspective view of a support member concerning an embodiment of the present invention. (A)-(e) is a partially broken perspective view which shows the construction method of the permeable purification body which concerns on embodiment of this invention. It is a perspective view which shows the modification of a support member.

  First, the purification wall B including the permeable purification body P will be described with reference to FIG.

  The purification wall B purifies the contaminated groundwater W contaminated by passing through the pollution source S, and is formed on the downstream side of the pollution source S. The contaminated groundwater W is purified by passing through the purification wall B to become purified groundwater W ′.

The purification wall B is formed by a plurality of permeable purification bodies P, P,... Arranged in a staggered manner in the ground.
Note that the permeable purifiers P, P,... May be arranged in a row or in a lattice.

  As shown in FIG. 2, the permeable purification body P is formed by filling the shaft 9 with the purification material 1.

  The purification material 1 is a mixture of crushed stone and reaction material. The mixing ratio can be changed as appropriate, and only the reaction material may be used. There is no restriction | limiting in the kind of reaction material, For example, iron powder, activated carbon, chelate resin, microorganisms, etc. can be used as a reaction material. What is necessary is just to select the kind of reaction material suitably according to a pollutant.

Of the plurality of permeable purification bodies P, P,..., At least one permeable purification body P has a built-in groundwater sampling structure.
The groundwater sampling structure is provided to collect groundwater in the permeable purification body P. The support member 2 embedded in the permeable purification body P and the permeable purification from the inside of the permeable purification body P. And a pipe 3 for collecting groundwater reaching the upper end of the body P.

  The support member 2 includes an outer frame portion 21 arranged along the inner peripheral wall of the shaft 9, and a plurality of (three in this embodiment) support portions 22, 22, which are directed from the outer frame portion 21 to the central portion of the shaft 9. 22 and a guide portion 23 rising from the outer frame portion 21.

  The outer frame portion 21 is made of a ring-shaped member having a smaller diameter than the inner diameter of the shaft 9. In the present embodiment, the case where the outer frame portion 21 is a circular ring (frame) is exemplified, but the shape and the like of the outer frame portion 21 are not limited. Although illustration is omitted, the outer frame portion may be polygonal.

The support part 22 consists of a rod-shaped member. As shown in FIG. 3, one end of the support portion 22 is joined to the outer frame portion 21, and the other end of the support portion 22 is the other portion in the central portion of the shaft 9 (the center portion of the outer frame portion 21). It is joined to the support part 22. That is, each support portion 22 intersects with another support portion 22 inside the outer frame portion 21. The plurality of support portions 22, 22, 22 are arranged radially from the center of the outer frame portion 21. Among the plurality of support portions 22, 22, 22, the support portions 22, 22 arranged on the upstream side of the intersecting portion between the support portions 22 (left side of the intersecting portion in FIG. 2) intersect the groundwater flow direction. Arranged along the direction.
Note that the number and arrangement of the support portions 22 may be changed as appropriate.

  The guide part 23 is a guide for making the pipe material 3 face the upper end of the shaft 9, and is made of a rod-shaped member. The guide portion 23 of the present embodiment is erected at the joint portion between the outer frame portion 21 and the support portion 22. The lower end portion of the guide portion 23 is joined to the outer frame portion 21. In this embodiment, although the upper end of the guide part 23 is located in the shaft 9, it does not mean that the length of the guide part 23 is limited. Although illustration is omitted, the upper end of the guide portion 23 may be positioned at the upper end of the shaft 9 or may protrude from the upper end of the shaft 9.

The pipe material 3 is arrange | positioned along the shaft 9 in the downstream (right side in FIG. 2) of the flow of groundwater. The lower part of the pipe material 3 is curved and extends to the central part of the shaft 9. The pipe material 3 of this embodiment consists of a flexible tube with an internal diameter of 10 mm or less. If a small diameter tube or the like is used, the flow of groundwater is not obstructed and the amount of collected water can be reduced.
A water sampling port 3 a for taking in the groundwater in the permeable purifier P into the pipe 3 is formed at the lower end of the pipe 3. The water sampling port 3a is disposed in the central portion of the shaft 9 (the central portion of the outer frame portion 21). In this embodiment, the water sampling port 3a of the pipe material 3 is covered with a filter (mesh member) for preventing clogging. Although not shown, a plurality of through holes provided in the pipe wall of the pipe material 3 may be used as the water sampling port.
The lower end portion of the tube material 3 is held by the support member 2. Although there is no restriction | limiting in the fixing method of the pipe material 3, What is necessary is just to wrap and wind the binding band, the number wire, etc. around the pipe material 3 and the support part 22, for example.

Next, the construction method of the permeable purifier according to this embodiment will be described.
The construction method of the permeable purifier according to the present embodiment mainly includes an excavation process and a filling process.

The excavation process is a process of forming the shaft 9 in the ground G including the contaminated groundwater as shown in FIG.
In the excavation process, the casing 4 is rotationally press-fitted by a casing rotary excavator (not shown), and the inside of the casing 4 is excavated from an opening at the upper end of the casing 4 using a hammer grab (not shown). In addition, there is no restriction | limiting in the formation method of the shaft 9, For example, you may perform the rotary press-in of the casing 4 and excavation of earth and sand with one construction machine by using a leader type casing rotary excavator. Further, the shaft 9 may be constructed by a method that does not use the casing 4.

In the filling step, as shown in FIGS. 4B to 4D, the purification material 1 is filled into the shaft 9, and the support member 2 holding the lower end portion of the tube material 3 is installed in the shaft 9 together with the tube material 3. It is a process to do.
The filling process of the present embodiment includes a first step (see FIG. 4B) in which the purification material 1 is filled up to the installation height of the support member 2, and a support member on the upper surface of the purification material 1 filled in the first step. 2 (see (c) of FIG. 4), a third step (see (d) of FIG. 4) of filling the purifying material 1 on the support member 2, and a second step of pulling out the casing 4 4 steps (see FIG. 4E).

In the first step, as shown in FIG. 4B, the purifying material 1 is filled from the bottom of the shaft 9 to the installation height of the support member 2 using a hopper (not shown).
In the second step, as shown in FIG. 4C, the outer frame portion 21 and the support portions 22, 22, and 22 of the support member 2 are placed on the upper surface of the purification material 1 filled in the first step. The tube material 3 is fixed in advance to the support portion 22 and the guide portion 23 of the support member 2. The support member 2 is disposed so that the guide portion 23 is located on the downstream side of the groundwater, and the pipe material 3 is disposed along the inner peripheral wall of the shaft 9. The outer diameter of the outer frame portion 21 of the support member 2 is smaller than the inner diameter of the casing 4.
In the third step, as shown in FIG. 4D, the purification material 1 is filled on the support member 2 using a hydraulic excavator or a charging pipe (not shown). Since the pipe material 3 is held by the guide portion 23 of the support member 2 and is disposed along the inner peripheral wall of the shaft 9, the tube material 3 is unlikely to become an obstacle when the purification material 1 is filled into the shaft 9. .
In addition, although illustration is abbreviate | omitted, when installing the several pipe material 3 from which the depth of a water sampling position differs in the shaft 9, it refine | purifies to the installation height of the other support member 2 installed above the support member 2 Fill material 1.
In the fourth step, as shown in FIG. 4E, the casing 4 is pulled up by a crane or the like (not shown). In the present embodiment, the casing 4 is pulled up when the purification material 1 is filled up to the upper end of the shaft 9, but the purification material 1 filling operation and the casing 4 lifting operation may be performed alternately.
When the purification material 1 is filled up to the upper end of the vertical shaft 9 and the casing 4 is all pulled out, the permeable purification body P is completed.

  According to the construction method of the permeable purifier according to the present embodiment, since the pipe member 3 for collecting groundwater is positioned using the support member 2, the position of the pipe member 3 is difficult to shift when the purifier 1 is filled. .

  That is, according to the groundwater sampling structure according to the present embodiment, since the lower end portion of the pipe material 3 is held by the support member 2, the water sampling port 3a of the pipe material 3 can be installed at a predetermined water sampling position, and thus Thus, it is possible to accurately grasp the effect of the permeable purifier P.

  In the groundwater sampling structure according to the present embodiment, the support member 2 includes the outer frame portion 21, and the outer frame portion 21 is disposed along the inner peripheral wall of the shaft 9 (the inner peripheral surface of the casing 4). Therefore, the support member 2 comes to be positioned along the inner peripheral wall of the shaft 9 only by placing the support member 2 on the upper surface of the purification material 1. That is, according to the groundwater sampling structure according to the present embodiment, the support member 2 itself becomes difficult to move, and consequently the installation accuracy of the water sampling port 3a is improved.

  Furthermore, if the lower end part of the pipe material 3 is fixed to the crossing part of several support parts 22,22,22, the water sampling port 3a can be stably fixed to a predetermined water sampling position.

  Moreover, since the support parts 22 and 22 arrange | positioned in the upstream of the water sampling port 3a are arrange | positioned along the direction which cross | intersects the flow direction of groundwater, the guide part 23 is arrange | positioned in the downstream of the water sampling port 3a. Even if a water channel is formed along the support unit 22 and the guide unit 23, the water passing through the water channel hardly flows into the water sampling port 3a. That is, according to the groundwater sampling structure according to the present embodiment, it is difficult for unpurified water to be mixed into the water sampled through the pipe material 3, so that the effect of the permeable purifier P can be accurately grasped. It becomes.

Note that the configuration of the support member 2 may be changed as appropriate.
For example, the outer frame portion 21 may be omitted.
Moreover, in this embodiment, although the case where the some support parts 22 and 22 crossed in the center part of the shaft 9 was illustrated, it is good also considering the support part 22 as one. In the case where one support portion 22 is used, only one end of the support portion 22 is joined to the outer frame portion 21 or both ends of the support portion 22 are joined to the outer frame portion 21. Moreover, in this embodiment, although the rod-shaped support part 22 was illustrated, a mesh-shaped support part may be used. The material of the support member 2 is not particularly limited.

Moreover, it may replace with the support member 2 and may use the support member 2a shown in FIG.
The support member 2a includes an outer frame portion 21a, a plurality of (three in this embodiment) support portions 22a, 22a, and 22a from the outer frame portion 21a toward the central portion of the shaft 9, and a guide portion that rises from the outer frame portion 21a. 23a and a pair of braces 24a, 24a that rise obliquely from the outer frame portion 21a toward the guide portion 23a.

The outer frame portion 21a has a C shape. Both end portions of the outer frame portion 21a are respectively joined to the end portions of the support portion 22a.
The configurations of the support portion 22a and the guide portion 23a are the same as the configurations of the support portion 22 and the guide portion 23 of the support member 2.
The brace 24a is a rod-shaped member that extends from the end of the outer frame portion 21a to the upper end of the guide portion 23a. The lower end portion of the brace 24a is joined to the outer frame portion 21a, and the upper end portion of the brace 24a is joined to the upper end portion of the guide portion 23a.

  According to the support member 2a of FIG. 5, since the outer frame portion 21a is interrupted on the upstream side of the groundwater flow, it is difficult to inhibit the flow of contaminated groundwater flowing into the permeable purifier P. Moreover, since the guide part 23a is supported by the braces 24a and 24a, the guide part 23a becomes difficult to deform | transform.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and it is needless to say that the above-described components can be appropriately changed in design without departing from the spirit of the present invention.

P permeable purification body 1 purification material 2 support member 21 outer frame portion 22 support portion 23 guide portion 3 pipe material 3a water sampling port 9 shaft

Claims (4)

An excavation process for forming a shaft in the ground containing contaminated groundwater;
A permeable purifier comprising a filling step of filling the vertical shaft with a purification material for purifying the contaminated groundwater, and installing a pipe for collecting groundwater and a support member holding the lower end of the pipe in the vertical shaft. The construction method of
The support member includes a ring-shaped outer frame portion disposed along an inner peripheral wall of the shaft, a rod-shaped support portion that extends from the outer frame portion toward the central portion of the shaft, and a rod-shaped support portion that rises from the outer frame portion. A guide portion,
The filling step is performed in the first step in which the purifying material is filled up to the installation height of the outer frame portion and the support portion , and the lower end portion of the pipe material is fixed to the support portion. wherein a and a second step of placing the outer frame portion and the support portion to the upper surface of the purification material, and a third step of filling the purification material on the outer frame portion and the support portion has,
A method for constructing a permeable purification body. A support member embedded in the permeable purifier filled in the shaft ,
A pipe for collecting groundwater from the inside of the permeable purification body to the upper end of the permeable purification body, and a groundwater collection structure comprising:
At the lower end portion of the pipe material, a water sampling port is formed for taking the groundwater in the permeable purification body into the pipe material,
The support member rises from the outer frame portion, a ring-shaped outer frame portion arranged along the inner peripheral wall of the shaft, a plurality of rod-shaped support portions from the outer frame portion toward the central portion of the shaft, and A rod-shaped guide portion ,
The pipe is held by the guide part,
The lower end portion of the tube material is fixed to the support portion.
Groundwater collection structure characterized by that. Based on groundwater flow,
Of the plurality of support portions, the support portion disposed on the upstream side of the water sampling port is disposed along a direction intersecting the flow direction of groundwater,
The groundwater sampling structure according to claim 2 , wherein: The guide part and the pipe are arranged along the inner peripheral wall of the shaft on the downstream side of the flow of groundwater,
The lower part of the pipe is bent,
The water sampling port is disposed in the central part of the shaft,
The groundwater sampling structure according to claim 2 or claim 3, wherein

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