KR20130070075A - A street tree box having function of sinking prevention - Google Patents

Abstract

PURPOSE: A roadside tree planting box is provided to simultaneously treat non-point pollutants, and to be able to prevent the settlement due to the subsidence of neighboring ground. CONSTITUTION: A main body(10) is open on the top, and formed with a planting and filtering space(S1) inside. A collecting chamber(20) has an overflow path which connects the upper part of the planning and filtering space and a collecting space(S2), and a drain gutter(70) which drains the inflow water of the collecting space. A subsidence prevention frame(100) is installed around the main body. A plant vegetation layer(30) is laminated in the planting and filtering space. The subsidence prevention frame comprises to form a lattice structure with multiple horizontal frames and multiple longitudinal frames. A mesh net is formed on the lattice formed by the horizontal frames. An upper medium layer(41) and a lower layer medium layers(42) are respectively laminated on the upper and lower parts of the planting and filtering space. A soil layer(50) is laminated between the upper and lower medium layers.

Description

A street tree box having function of sinking prevention}

The present invention utilizes the tree space of the road to establish a water circulation environment and to efficiently treat non-point pollutants, to provide sufficient moisture to planted trees, and to selectively treat rainfall runoff. It relates to a tree planting box to prevent settlement.

Roads are generally planted on roads. Street trees provide pleasant feelings and psychological stability for pedestrians, drivers and others, absorbing solar heat, blocking or reducing snow, rain, and fog, and alleviating the effects of wind to reduce microclimate control effects. And the branches and leaves of the water pipe has a function of adsorbing dust and dust, and absorbs harmful gases to purify the air.

These street trees have beautiful linear beauty as sculptures, used for water walls and backgrounds, have decorative effects, soften the heavy feeling of urban buildings, and create living spaces in other areas around them. It protects the privacy by separating from the space, and efficiently divides and uses the space. As an engineering effect, it prevents erosion due to soil stabilization, blocks noise, provides sound insulation effect, and has a function as a fire zone.

In the conventional tree planting technique, the above-mentioned functions and effects are merely expected. Recently, various treatment facilities for non-point pollutants, such as rainfall runoff, have been developed in addition to point pollutants such as domestic waste, industrial waste, and industrial waste water.

Most non-point pollutant treatment facilities are classified into natural type and device type, and natural type includes infiltration filtration type, ecological packing filter type, vegetation biofilter type, curb filter type and rain garden type. Vortex type, hydraulic filter type and tribox filter type facilities are available.

In the case of the tribox filter type non-point pollutant treatment facility, the non-point pollutant can be treated while having a vegetation space where roadside trees are planted or flower beds are formed.

Such a tree box filter type non-point pollutant treatment facility is provided with a box body provided with an inlet such as rainfall runoff at the top of one side, and forming a roadside tree or a flower bed, and a media layer filled in the inner bottom of the box body, and the media layer. It includes a vegetation soil layer filled in the upper portion of the box body, and a drain pipe for draining the treated water filtered by the filter medium layer in the ground or rainwater pipe or the sump tank.

In addition, the inlet provided at the upper end of the box body is disposed toward the road so that rainfall runoff flowing along the road can be introduced when the tree box filter type non-point pollutant treatment facility is installed on the road side.

However, in the conventional tribox-type non-point pollutant treatment facility, rainfall runoff flowed into the box body through the inlet from the road side is filtered downward while passing downward through the vegetation soil layer and the media layer, and the ground or rainwater pipe through the drain pipe provided at the bottom of the box body. It is drained to a furnace or a sump, and rainfall runoff water containing a large amount of nonpoint pollutants, as well as rainfall runoff water containing a small amount of nonpoint pollutants after the initial rainfall, are filtered through vegetation soil and media layers, and then drained. There is a problem in that the efficient treatment according to the inflow amount of rainfall runoff because it is drained through.

In addition, since the initial rainfall runoff water containing a large amount of nonpoint pollutants as well as rainfall runoff water containing a small amount of nonpoint pollutants after the initial rainfall was passed through the filter bed, there was a problem that the filtration load of the filter bed layer increases.

In addition, in the conventional tribox-type nonpoint pollutant treatment facility, the rainfall runoff flows downwardly through the vegetation soil layer and the medial layer, and then is drained through a drain pipe provided at the bottom, and the rainfall runoff is not stored in the vegetation soil layer and the medial layer. Therefore, there is a problem that the vegetation environment of the tree is poor because it does not secure enough moisture for the growth of trees such as roadside trees.

In particular, the conventional tribox-type non-point pollutant treatment facility has a problem that the surrounding ground is settled by the weight of the facility itself.

Therefore, the present invention has been made to solve the above problems, by using the tree space of the road to efficiently build a water circulation environment and to implement the treatment of non-point pollutants at the same time as well as the settlement of the surrounding ground The purpose is to provide a tree planting box that can prevent sag due to.

A tree planting box according to the present invention is the top is open to achieve the above object and the body is formed with a planting and filtering space therein; In the planting and filtering space is installed at a relatively lower position than the upper end of the main body, the catchment space for collecting the inflow water therein and the upper flow passage and the collecting space of the upper portion of the planting and filtering space and the collecting space A collecting chamber provided with a drain passage for draining the inflow water; Settlement prevention frame is installed in the periphery of the main body; And a tree vegetation layer laminated on the planting material and filtration space.

Herein, the anti-sedimentation frame is configured around the main body, characterized in that the plurality of horizontal frames and the plurality of vertical frames are configured to form a lattice structure.

In addition, a mesh network may be intermittently formed in the grating formed by the horizontal frame.

In addition, a plurality of flow holes may be formed in the main body so that water may flow between the main body and the surrounding ground.

On the other hand, the tree vegetation layer, the upper and lower media layers stacked on the upper and lower portions of the planting and filtering space, respectively; And it characterized in that it comprises a soil layer laminated between the upper and lower media layers. Here, the upper media layer is characterized by consisting of crushed stone, the drainage passage is configured with a reverse displacement.

On the other hand, the collection chamber, it is preferable to further include at least one of the water passages for communicating the planting and filtering space of the water collecting space and the body. In addition, it is reasonable to further include a filter medium filled in the overflow passage or the permeate passage.

On the other hand, the main body is characterized in that the underground water passage is formed in communication with the ground.

As described above, the tree planting box with a sinking prevention function according to the present invention can be implemented by using the tree space of the road to implement the water circulation environment, treatment of non-point pollutants and prevention of sinking at the same time. .

Rainfall runoff introduced into the planting and filtration space of the body is subjected to a top-down filtration process and a bottom-up filtration process, thereby improving the removal efficiency of non-point pollutants.

It also has a catchment chamber that is higher than the bottom of the tree planting box and lower than the top of the tree planting box, and the overflow passage lower than the top of the catchment chamber and higher than the bottom of the catch chamber, and includes a large amount of non-point pollutants. The effluent is filtered to allow ground penetration, and rainfall runoff that contains a small amount of non-point pollutants after a certain period of time after initial rainfall is not filtered but is drained to rainwater pipes or sump wells to effectively treat nonpoint pollutants. It is effective to build a water circulation environment.

In addition, a water permeation passage is provided in the lower part of the collection chamber to store a certain amount of rainfall runoff after the end of the rainfall, so that the rainfall runoff gradually penetrates into the tree vegetation to secure enough water for the growth of vegetation trees. It has the effect of being able to grow.

In addition, by forming a lattice-type subsidence prevention frame at the periphery of the main body, there is an effect of preventing the sagging of the box due to the subsidence of the surrounding ground which may be caused by excessive penetration of moisture, imposition of excessive load, etc. during use.

1 is a longitudinal sectional view showing a tree planting box with a sinking prevention function of the present invention.
2 is a sectional view taken along the line AA in Fig.
3 is a sectional view taken along line BB of Fig.
Figures 4a to 4c is a schematic diagram showing an embodiment of a tree planting box with a settlement prevention function of the present invention.
5 is a plan view showing a preferred embodiment of the tree space composition structure to which the tree planting box according to the present invention is applied.
6 is a sectional view taken along the line DD of FIG. 5.
7 is a cross-sectional view taken along line EE of FIG. 5.
8 is a cross-sectional view taken along line FF of FIG. 5.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

As shown in Figs. 1 to 3, the tree planting box with a settlement prevention function according to the present invention, the main body 10 is buried in the ground, the main body 10 is provided in the inflow water including rainfall runoff A collection vegetation layer for planting a vegetation (P), including a tree, which is stacked in the collection chamber 20 for collecting and draining, the settling prevention frame 100 configured at the periphery of the main body 10, and the main body 10. It comprises 30.

The main body 10 is configured to accommodate the tree vegetation layer 30, and a planting material and a filtration space S1 are formed therein, and an upper portion thereof is opened so that an inflow water including rainfall runoff is introduced.

As an example, the main body 10 may be configured in a rectangular parallelepiped shape as shown in FIG. 1, and in this case, the main body 10 includes front and rear walls 12 and 13 that form an outer wall with the base plate 11. ) And left and right walls 14 and 15.

Here, the main body 10 is not limited to the rectangular parallelepiped shape shown in FIG. 1 and the like in its shape, and may be configured in various shapes such as a cylindrical shape.

In embedding the main body 10 in the ground, after the trench is installed, the rubble compaction layer 16 is installed on the bottom thereof, and the main body 10 is seated on the upper part, and then the settlement prevention frame 100 to be described below. It is installed on the periphery of the main body 10, and the main body 10 is embedded in the ground by backfilling so that the main body 10 is firmly fixed.

The anti-sedimentation frame 100 is to prevent the subsidence of the surrounding ground by being buried in the ground around the main body 10 to prevent the main body 10 from sagging to the ground.

In addition, the top height of the main body 10 is lower than or equal to the road surface of the sidewalk (R1) and the roadway (R2) so that the rainfall runoff flowing along the sidewalk (R1) and the roadway (R2), that is, the top of the body (10) The upper and rear walls 12 and 13 and the left and right walls 14 and 15 of the main body 10 are overflowed so as to flow into the planting and filtering space S1.

As such, the main body 10 may allow the rainfall runoff to naturally flow in by the position thereof, but is not limited thereto. However, the main body 10 may be connected to a separate inlet pipe through which the rainfall runoff flows. .

The main body 10 may be made of various materials such as iron, plastic, concrete, and may be selectively configured in consideration of site conditions.

On the other hand, the collection chamber 20 is a component mounted on the planting material and filtration space (S1) of the main body 10 may be manufactured separately and combined with the main body 10, but is integrally configured with the main body 10 It is desirable to.

The collection chamber 20 is provided with a collecting space S2 for collecting inflow water including rainfall outflow therein, and may be manufactured in various shapes like the main body 10 described above, and formed in a rectangular parallelepiped as shown in the example. If so, the water collecting space S2 may be formed by the bottom plate body 21, the front and rear walls 22 and 23, and the left and right walls 24 and 25.

In addition, the collection chamber 20 is composed of a bottom plate 21 and one left wall 24 so that the collecting space S2 is the bottom plate 21 and one left wall 24, and the It may be formed by any one of the wall 15 and the front and rear walls 12 and 13 of the left and right walls 14 and 15 of the main body 10.

The collecting chamber 20 is installed at a position relatively lower than the upper end of the main body 10 in the planting and filtering space (S1) of the main body 10.

That is, the bottom plate body 21 of the collecting chamber 20 is installed at a position higher than the bottom plate body 11 of the main body 10 and lower than the upper end of the front and rear walls 12 and 13 and the left and right walls 14 and 15. The front and rear walls 22 and 23 and the left and right walls 24 and 25 have upper ends lower than upper ends of the front and rear walls 12 and 13 and the left and right walls 14 and 15 of the main body 10. .

The upper portion of the sump chamber 20 is also opened to allow the inflow water including rainfall runoff to flow in. The opening is preferably covered by a grating 26.

The grating 26 is intended to prevent the floating material having a predetermined size or more contained in the rainfall runoff to be introduced into the collecting space S2.

In addition, the water collection chamber 20 may include the overflow passage 60 and the drain passage 70, and the overflow passage 60 is not shown in the drawings, but the wall 22 of the collection chamber 20 is formed. , 23, 24, 25 may be composed of the overflow hole perforated in any one of the wall through the wall of the collection chamber (20).

At the inlet side of the overflow passage 60, it is preferable that the filter medium 61 is filled in order to prevent non-point pollutants such as suspended substances collected in the tree vegetation layer 30 from entering the collecting space S2. Do.

The filter medium 61 is not limited to the material and non-point pollutants, including suspended solids and the like while passing through the water particles may be used any filter medium that can be filtered, preferably using a mesh, more preferably Is semi-permanent and can be recycled and made of stainless steel to resist corrosion by water.

The drain passage 70 is connected to the lower end of the collection chamber 20 and may be connected to a manhole or collection well 3 installed between the sidewalk R1 and the driveway R2.

The drainage passage 70 is the collection chamber 20 and the manhole or the sump (3) according to the conditions of the installation place of the tree structure structure for the construction of the water circulation environment according to the present invention as shown in FIG. It can be installed linearly or by-pass between them.

Here, although not shown in the drawing, the drain passage 70 may be configured to reverse the flow of water to flow in only one direction.

This prevents rainwater from flowing back from the manhole or sump 3 during the rainy season during the rainy season as the drain passage 70 is connected to the manhole or the sump 3 so that the nonpoint pollutant substances included in the rainwater may be collected. It is to prevent the inflow into the chamber 20 and the main body 10.

As described above, the present invention is provided with the above-mentioned collecting chamber 20 and the overflow passage 60 lower than the upper end of the collecting chamber 20 and higher than the lower end of the collecting chamber 20. The initial rainfall runoff is filtered to allow it to penetrate the ground.

Rainfall runoff water containing a small amount of nonpoint pollutants after a certain period of time after initial rainfall is not filtered but drained to rainwater pipes or sump tanks to effectively treat nonpoint pollutants such as to create an optimal water circulation environment. Will be.

On the other hand, the tree vegetation layer 30 is laminated in the planting and filtering space (S1), as shown in Figures 1 to 3, the upper media layer 41 and the lower media layer 42 and the soil layer 50 It may be configured to include).

The lower layer filter layer 42 is used for downward filtration and upward filtration, and the lower layer filter layer 41 may use sand and / or gravel.

The soil layer 50 may use a mixed soil or nutrient soil for the local soil or vegetation.

The upper media layer 41 may be composed of gravel, but because the specific surface area has a large porosity, wood chips (to improve the removal efficiency of particulate and dissolved contaminants in adsorption and filtration of fine soils or heavy metals) wood chip) may be used, or crushed stone may be used.

In particular, the settling prevention frame 100 is configured at the periphery of the main body 10, and the ground of the periphery of the main body 10 is prevented from settling based on the settling prevention frame 100.

Herein, the anti-sedimentation frame 100 is configured such that the plurality of horizontal frames 110 and the plurality of vertical frames 120 form a lattice structure, as shown in FIG. 1, such that the horizontal frame 110 and the vertical frame 120 are formed. The subsidence prevention frame 100 is formed of a plurality of gratings formed by the peripheral portion of the main body 10.

That is, the lattice-type anti-sedimentation frame 100 is configured at the periphery of the main body 10 so that the soil is filled with each lattice, and the anti-sedimentation frame 100 acts as a supporting structure on the ground at the periphery of the main body 10. By doing so, it is possible to prevent the ground around the main body 10 from being settled due to excessive penetration of moisture, the weight of the main body 10, or the like.

The settling prevention frame 100 may be installed in the periphery of the main body 10 separately from the main body 10, but as shown in FIG. 4A, the locking protrusions 10 are formed on the outer periphery of the main body 10 and protrude. It may be configured to be able to be integrated with the main body 10 by fastening the settling prevention frame 100 to the -1) using a rebar. In this way, by enabling integral behavior, the settlement function can be further doubled.

In addition, as shown in FIG. 4B, the mesh network 130 may be intermittently configured in the grid formed by the horizontal frame 110.

That is, in the anti-sedimentation frame 100, a plurality of grids formed by the horizontal frame 110 selectively constitute a mesh network 130 as necessary so that the anti-sedimentation frame 100 is grounded around the main body 10. The resistance to longitudinal settlement and deflection can be improved.

The mesh network 130 is appropriate to select the diameter of the mesh in consideration of the particles of the soil to be covered.

In addition, the main body 10 includes a plurality of flow holes 12-1 and 13 in the side walls of the main body 10, that is, the front and rear walls 12 and 13 and the left and right wall bodies 14 and 15, as shown in FIG. 4C. -1, 14-1, and 15-1 are configured to allow the flow of water between the inside of the main body 10 and the periphery of the main body 10 to be configured.

This configuration is to prevent ground subsidence due to the imbalance of moisture contained between the inside of the body 10 and the periphery of the body 10, and to prevent settlements that may be caused by excessive water imbalance such as rainwater. .

Hereinafter will be described the operation of the tree planting box with a sinking prevention function according to the present invention configured as described above.

The tree planting box according to the present invention is installed on the vegetation zone between the sidewalk R1 and the roadway R2, and is installed on the sidewalk R2, which is a typical roadside installation area.

In the installation of the main body 10, the rainwater runoff flowing on the sidewalk (R1) or the roadway (R2) at the time of rainfall is installed so as to be introduced into the planting and filtering space (S1) of the main body 10 and the drainage The passage 70 is installed to be connected to the manhole or the sump 3.

At this time, if necessary, it is also possible to connect the rainfall outflow water inlet pipe to the main body 10 separately.

The vegetation (P) to be planted in the main body 10 is laminated to the lower layer filter layer 42 and the soil layer 50 in the planting and filtering space (S1) of the main body 10, the upper layer filter layer 41 It is planted in the soil layer 50 before laminating, and then the upper layer filtering layer 41 is laminated on the soil layer 40.

In addition, the manhole or the sump (3) can be installed in advance before using the existing installation or planting the tree planting box according to the invention.

Rainfall runoff water generated during the rain in the installation is completed, the overflow of the front and rear walls 12, 13 and the left and right walls 14, 15 of the tree planting box body 10 to the planting and filtering space (S1) Inflow.

Rainfall effluent flowing into the planting and filtration space (S1) is filtered downward while passing through the upper filter layer (41), and the rainfall effluent passing through the upper filter layer (41) is the soil layer (50) It is filtered downward while passing downward, and is filtered downward downward while passing downwardly through the lower media layer 42.

Rainfall outflow water filtered downward through the lower media layer 42 is filled from the bottom of the planting and filtration space (S1).

Rainfall runoff from the bottom of the planting and filtration space (S1) is again filtered through the bottom filter layer 42 and the soil layer 50 and the upper filter layer 41 upward again.

As such, the rainfall runoff flowing into the planting material and the filtration space S1 of the main body 10 is filtered downward while passing downwardly through the upper filter layer 41, the soil layer 50, and the lower filter media layer 42. It is filtered from the bottom of the planting material and the filtration space (S1) of the main body 10 is filtered upward to remove the non-point pollutants contained in the rainfall effluent sufficiently.

Here, when the water level of rainfall runoff rising from the lower end of the planting and filtration space (S1) of the main body 10 reaches the upper media layer 41 and the overflow passage 60, the rainfall runoff flows through the overflow passage 60 The water flows through and flows into the water collecting space S2 of the water collecting chamber 20 to be collected.

At this time, since the filter medium 61 is provided at the inlet side of the overflow passage 60, the non-point contaminant such as the suspended solids collected in the upper filter layer 41 is introduced into the collecting space S2. After filtration once more by the flow into the collecting space (S2) of the collecting chamber (20).

Therefore, the non-point pollutant is sufficiently removed in the rainfall effluent collected in the collecting space S2 of the collecting chamber 20.

Rainfall runoff is rapidly increased due to continuous rainfall or heavy rain, and the level of rainfall runoff flowed into the planting and filtration spaces S1 of the main body 10 is increased from the front and rear walls 22 and 23 of the collection chamber 20. When it is higher than the upper end of the left and right walls 24 and 25, the rainfall runoff flowing into the planting material and the filtration space S1 of the main body 10 is the front and rear walls 22 and 23 and the left and right walls ( 24 and 25 are overflowed to the collecting space S2 of the collecting chamber 20.

The collecting chamber 20 is composed of a bottom plate 21 and one left wall 24 so that the collecting space S2 is the bottom plate 21 and one left wall 24, and the main body 10. In the case of any one of the left and right walls 14 and 15 of the wall 14 and the front and rear walls 12 and 13, the rainfall runoff that fills the planting and filtering spaces S1 of the main body 10 is the left wall. Overflow of the (24) flows into the collecting space (S2) of the collecting chamber (20).

In this case, the rainfall runoff flows directly into the collecting space S2 of the collecting chamber 20 without undergoing the downward filtration process and the upward filtration process as described above.

Rainfall outflow water introduced into the collection space (S2) of the collection chamber 20 is drained to the manhole or the sump (3) through the drainage passage (70).

On the other hand, according to an embodiment of the present invention, the collecting chamber 20 is lower, that is, the bottom plate body 21 of the collecting chamber 20, the collecting and filtering of the collecting space (S2) and the main body 10 One or more pitcher passages 80 communicating with the space S1 may be further included.

The water permeable passage 80 may be composed of a plurality of perforation holes perforated in the bottom plate body 21 of the collection chamber 20, or may be composed of a plurality of water permeable pipes penetrating the bottom plate body 21.

Rainfall outflow water introduced into the collection space (S2) of the collection chamber 20 is drained to the outside through most of the drain passage 70, but a part of the planting of the main body 10 again through the water passage passage (80) It is provided as water necessary for vegetation of the vegetation (P) planted in the soil layer 50 is stacked in the filtration space (S1) to ensure sufficient moisture for the growth of planted vegetation (P) plant (P) can grow actively.

At this time, the permeable passage 80 is preferably filled with the filter medium 61, like the above-described overflow passage 60, whereby the non-point pollutants contained in the rainfall runoff water collected in the collecting space (S2) once more It is filtered to be permeable into the filtration space (S1).

In addition, according to an embodiment of the present invention, the body 10 may further include a ground permeable passage 90 communicating with the ground at the bottom thereof, that is, the bottom plate body 11 of the body 10.

The underground water passage 90 is to allow the rainwater discharged water remaining in the planting material and the filtration space (S1) of the main body 10 into the ground, an excessively large amount in the planting and filtration space (S1). Rainfall runoff is to prevent the long-term retention of the planted tree (P) due to excessive moisture.

The underground water passage 90 may be composed of a plurality of underground water holes perforated in the bottom plate body 11, or may be composed of underground water pipes penetrating the bottom plate body 11.

Thus, by using the above-described present invention, it is possible to simultaneously implement the water circulation environment and the treatment of non-point pollutants by utilizing the tree space.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of the invention.

10: main body 20: collection chamber
30: tree vegetation layer 41: upper layer filter layer
42: lower layer media layer 50: soil layer
60: overflow passage 70: drain passage
80: pitcher passage 90: underground pitch passage
100: sag prevention frame 110: horizontal frame

Claims (11)

A main body which is open at an upper portion and a planting and filtering space is formed therein;
It is installed at a position lower than the upper end of the main body in the planting and filtration space, the catchment space for collecting the inflow water therein and the upper flow passage and the collecting space communicating the upper portion of the planting and filtration space and the collecting space A collecting chamber provided with a drain passage for draining the inflow water;
Settlement prevention frame is installed in the peripheral portion; And
The tree planting box with a sinking prevention function, characterized in that it comprises a; a plant vegetation layer is laminated to the planting and filtering space.
The method of claim 1,
The settling prevention frame,
The tree planting box is configured in the periphery of the main body, the plurality of horizontal frames and the plurality of vertical frames are configured to form a lattice structure.
The method of claim 2,
The grid formed by the horizontal frame is a tree planting box with a settlement prevention function, characterized in that the mesh network is configured.
The method of claim 1,
The tree planting box with a sinking prevention function, characterized in that the plurality of flow holes are formed in the main body.
The method of claim 1,
The tree vegetation layer is
Upper and lower media layers stacked on the top and bottom of the planting and filtration space, respectively; And
A tree planting box with a settlement prevention function, characterized in that it comprises a soil layer laminated between the upper and lower media layers.
6. The method of claim 5,
The upper layer of media
A tree planting box with a settlement prevention function, characterized in that composed of crushed stone.
The method of claim 1,
The tree planting box with a sinking prevention function, characterized in that the reverse passage is configured in the drain passage.
The method of claim 1,
The collecting chamber,
A tree planting box having a sinking prevention function further comprises at least one water passage for communicating the water collecting space and the planting material and filtration space of the main body in the lower portion.
The method of claim 8,
The catch chamber is
A tree planting box with a settlement prevention function, characterized in that it further comprises a filter medium filled in the overflow passage or the pitcher passage.
The method of claim 1,
The body
A tree planting box with a sinking prevention function, characterized in that the ground permeable passage communicating with the ground is formed in the lower portion.
11. The water circulation type road structure according to any one of claims 1 to 10, wherein the tree planting box having a function of preventing settlement is formed while forming a predetermined gap.

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