JP7329249B2 - Managed seawall - Google Patents

Description

TECHNICAL FIELD The present invention relates to a controlled seawall, and more particularly, to a surface impermeable work using a impermeable sheet to impermeable water between a waste disposal site and the sea.

In the conventional landfill revetment, in order to prevent the landfill soil on the back from flowing out to the sea side through the riprap embankment or riprap mound with a large porosity and causing the back landfill ground to collapse, civil engineering systems such as anti-sand sheets and asphalt mats are used. After using a membrane, landfill soil is put in to create a landfill site. Since the landfill material is earth and sand, even if it flows into the sea area, it does not cause any major environmental problems. A possible permeable membrane is considered desirable.

On the other hand, in controlled waste landfill revetments (managed revetments), the outflow and seepage of waste and retained water outside the revetment area is strictly regulated by law. Impermeability is required. The more impermeable, the less the Pascal pressure decays, requiring a human counterforce to counteract the natural forces acting on it.

To further illustrate, a controlled waste landfill seawall must prevent the outflow of waste and the seepage of retained water into the seabed of the waste disposal area and the waters outside the waste disposal site. not. Therefore, the structure of the managed revetment is different from that of ordinary reclaimed revetments, and is a water-blocking revetment with water-blocking work.

Here, the conventional managed bank protection 301 will be described with reference to FIG. The managed revetment 301 consists of a riprap embankment 305 installed on an impermeable improved base 303, a ground treatment crushed stone layer 307, an impermeable sheet (lower impermeable sheet) 309, an intermediate protective crushed stone layer 311, and an impermeable sheet. (Upper waterproof sheet) 313 and a covering protective crushed stone layer 315 are provided.

The subfloor crushed stone layer 307 covers the rubble dike 305 on the waste disposal site side. The impervious sheet 309 covers the ground crushed stone layer 307 . An intermediate protective crushed stone layer 311 covers the waterproof sheet 309 . A waterproof sheet 313 covers the intermediate protective crushed stone layer 311 . A covering protective crushed stone layer 315 covers the impervious sheet 313 .

In the conventional managed revetment 301, as shown by arrows in FIG. Natural external forces act.

The porosity of the rubble dyke 305 is 40% to 50%. As a result, the natural external force (Pascal pressure) that permeates the rubble dyke 305 is hardly attenuated, and almost 100% of the natural external force acts on the non-permeable membrane of the impermeable sheet 309 .

In particular, when using a water-impervious sheet, which is a surface water-impermeable work, the thin (normal thickness is 3 mm) and light-weight water-impervious sheet is a non-permeable membrane (thin film), so the natural external force is almost 100%. % as the surface pressure of the waterproof sheet.

Therefore, there is a risk that the impermeable sheet will be turned up during construction, or that it will be locally damaged even after the completion of the controlled revetment.

Therefore, in the conventional management type revetment 301 , the intermediate protective crushed stone layer 311 is thickened to prevent the impervious sheet 309 from lifting due to the natural external force due to the weight of the intermediate protective crushed stone layer 311 .

That is, an impermeable membrane structure such as a waterproof sheet provides an artificial reaction force (intermediate protective layer) 311 that resists Pascal pressure (uplift).

Although no caissons or cells are provided in FIG. 7, a thick intermediate protective crushed stone layer 311 is similarly provided in the case of a hybrid embankment with caissons or cells installed on the rubble embankment 305 .

Here, Japanese Patent Laid-Open No. 2002-200011 is cited as a document related to the conventional technology.

Japanese Patent Application Laid-Open No. 2003-320335

In the conventional management type revetment 301, as described above, the intermediate protective crushed stone layer 311 is thickened in order to prevent the impervious sheet 309 from lifting due to natural external force. As a result, the volume of the waste disposal site will decrease, and the cross-sectional area of the controlled revetment will increase, increasing the construction cost and extending the construction period.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a controlled seawall that can avoid a reduction in the volume of a waste disposal site as much as possible, an increase in construction costs, and an extension of the construction period. do.

The invention according to claim 1 comprises: a riprap dyke constructed on an impermeable improved base; a seepage control sheet provided on the riprap dyke; It is a managed revetment with a natural external force permeation suppression membrane layer.

The invention according to claim 2 is the controlled seawall according to claim 1, wherein the impervious sheet covers the rubble dyke on the waste disposal site side, and the natural external force permeation suppression membrane The formation is a controlled revetment covering the riprap dyke on the seaward side.

The invention according to claim 3 is the controlled seawall according to claim 1, wherein the impervious sheet covers the rubble dyke on the waste disposal site side, and the natural external force permeation suppression membrane The layer is a controlled revetment installed within the rubble dyke.

The invention according to claim 4 is a managed seawall in which the natural external force permeation suppression membrane layer is composed of a vertical impermeable wall.

The invention according to claim 5 is the managed seawall according to claim 2 or 3, wherein the natural external force permeation suppressing membrane layer fills the gaps between rubble stones constituting the rubble dyke with seawater. It is composed of a material that reduces the natural external force applied to the impermeable sheet by passing through, and is equipped with a ground treatment crushed stone layer, an intermediate protective crushed stone layer, and a covering protective crushed stone layer, and the impermeable sheet is two sheets The ground crushed stone layer covers the rubble embankment on the waste disposal site side, and the first of the two impermeable sheets covers the ground crushed stone layer. The intermediate protective crushed stone layer covers the first impermeable sheet, and the second impermeable sheet of the two impermeable sheets covers the intermediate protective crushed stone layer. , the protective crushed stone layer covers the second impermeable sheet.

The invention according to claim 6 is the managed bank revetment according to claim 2 or 3, wherein the membrane layer for suppressing the permeation of natural external forces passes through the gaps between rubble stones forming the rubble dyke. The impermeable sheet is composed of a material that eliminates the natural external force applied to the impermeable sheet, and includes a ground treatment crushed stone layer and a coated protective crushed stone layer, one impermeable sheet is provided, and the ground treatment The crushed stone layer covers the rubble embankment on the waste disposal site side, the impermeable sheet covers the ground treatment crushed stone layer, and the coated protective crushed stone layer covers the impermeable sheet. is.

Advantageous Effects of Invention According to the present invention, it is possible to avoid a reduction in the volume of a waste disposal site as much as possible, an increase in construction costs, and an extension of the construction period.

1 is a cross-sectional view of a managed bank protection according to an embodiment of the present invention (a cross-sectional view of a plane perpendicular to the extension direction of the managed bank protection). It is sectional drawing of the management type|mold seawall which concerns on the 1st application example. It is sectional drawing of the management type|mold seawall which concerns on the 2nd example of application. It is sectional drawing of the management type|mold seawall which concerns on the 3rd example of application. It is sectional drawing of the management type|mold seawall which concerns on the 4th application example. It is sectional drawing of the management type|mold seawall which concerns on the 5th application example. It is sectional drawing of the conventional management type seawall.

A managed revetment (a managed waste landfill revetment; a managed revetment by a non-permeable revetment) 1 according to an embodiment of the present invention is employed in a waste disposal site 3. As shown in FIG. It is composed of a rubble embankment 5 , an impermeable sheet (water impermeable work) 7 , and a natural external force (Pascal pressure) permeation suppressing membrane layer (seawater permeation suppressing membrane layer; sheet-like seawater permeation suppressing material) 9 .

Here, for the sake of explanation, a predetermined one direction perpendicular to the vertical direction is defined as the inside-out direction, and a direction perpendicular to the vertical direction and the inside-out direction is defined as the lateral direction. The inner side in the inward/outward direction is on the side of the waste disposal site 3, and the outer side in the inward/outward direction is on the sea side. In each figure, the vertical direction of the paper surface is the vertical direction of the management type revetment 1, the horizontal direction of the paper surface is the inside and outside direction, and the direction perpendicular to the paper surface is the horizontal direction. Therefore, the managed revetment 1 extends in the horizontal direction. In addition, the management type revetment 1 does not necessarily extend in a straight line, but may extend in a curved or bent manner.

The rubble dyke 5 is constructed on the ground 11 (impermeable improved base 13). The impervious sheet 7 is provided on the rubble dike 5 on the waste disposal site 3 side. The ground 11 includes an impermeable layer (impermeable base) 17 made of rock or the like, layers (impermeable improved base) 13 and 15 treated to improve impermeability, and improved impermeability. and layers (permeable seabed ground) 19, 21 that have not been treated.

Although details are not shown, the impermeable sheet 7 includes a first protective mat, one impermeable impermeable sheet main body laminated on the first protective mat, and the first protective mat. It has a three-layer structure including a second protective mat laminated on one impermeable waterproof sheet body on the opposite side of the first protective mat. By providing the impermeable sheet 7, the impermeability of the management type revetment 1 is maintained.

In other words, the water-blocking sheet 7 blocks (water-blocking) the waste disposal site 3 from the sea, preventing the waste and retained water from flowing into the sea from the waste disposal site 3. ing.

The main body of the impermeable sheet is made of a material such as synthetic resin, synthetic rubber, or asphalt. For example, a reinforcing material (not shown) formed in a mesh shape is used as a core material in the main body of the impermeable sheet. It may be in. The protective mat protects the waterproof sheet body and is made of nonwoven fabric or synthetic resin. The impermeable sheet 7 covers the rubble dyke 5 and the vicinity of the riprap 5 of the impermeable base 13 .

In the impermeable sheet 7, the thickness direction of the impermeable sheet main body and the thickness direction of the protective mat coincide with each other. The protective mat is attached to the impermeable sheet main body by, for example, an adhesive, and the impermeable sheet main body and the protective mat are integrated. In addition, the impervious sheet 7 is formed in the shape of a thin plate having some flexibility.

The natural external force permeation suppression membrane layer 9 is provided on the rubble dyke 5 on the sea side of the impermeable sheet 7 . The natural external force permeation suppression membrane layer 9 is composed of a material whose seawater permeability is lower than that of the riprap ridge 5, or is composed of a material that does not allow seawater to pass through. .

That is, the natural external force permeation suppression membrane layer 9 reduces the natural external force applied to the impervious sheet 7 by allowing seawater to pass through the gaps between the rubble stones forming the rubble dyke 5, or forms the rubble dyke 5. It is provided to eliminate the natural external force applied to the impermeable sheet 7 due to seawater passing through the gaps between the riprap.

Natural external forces include tidal currents (tidal pressure; pressure generated by tidal currents), waves (wave pressure; pressure generated by waves), tides (tidal fluctuation pressure; pressure generated by tides), wind (wind pressure; pressure), etc., can be mentioned.

The specific gravity of the natural external force permeation suppressing membrane layer 9 is 1.03 or more, which is heavier than seawater, and naturally sinks in seawater.

A precast product is used as the membrane layer 9 for suppressing natural external force permeation. The natural external force permeation suppression membrane layer 9 is installed, laid or cast on site. As a result, a managed revetment can be installed at low cost in a short construction period.

In the case where the natural external force permeation suppressing membrane layer 9 is impermeable to water and eliminates the natural external force applied to the impermeable sheet 7, the natural external force permeation suppressing membrane layer 9 is non-seawater. It may also be called a permeable membrane layer (impermeable membrane layer). The seawater impermeable membrane layer 9 also isolates the waste disposal site 3 from the sea, preventing water from the sea side from flowing into the waste disposal site 3 .

The impermeable sheet 7 covers the rubble dyke 5 and the vicinity of the riprap dyke 5 of the impermeable base 13 on the waste disposal site 3 side (land side; inner side). A natural external force permeation suppression membrane layer 9 covers the rubble dyke 5 on the side opposite to the waste disposal site 3 (sea side; outside).

For example, one natural external force permeation suppression membrane layer 9 is provided. As the natural external force permeation suppression membrane layer 9, asphalt mats, rubber mats, iron plates, sheets, cloth-like fibrous bodies (woven fabrics and non-woven fabrics), concrete plates, and advance foam manufactured by Taiyo Kogyo Co., Ltd. are represented. Bag formwork (filling material such as solidified soil in the bag formwork) can be listed.

In the managed revetment 1 shown in FIG. 1, the natural external force permeation suppression membrane layer 9 reduces the natural external force applied to the impervious sheet 7 by allowing seawater to pass through the gaps between the rubble stones forming the rubble dyke 5. made up of materials. A material that reduces the natural external force is a material that allows seawater to pass through but gives resistance to the flow of seawater.

To explain further, the natural external force permeation suppression membrane layer 9 is made of a material that reduces the amount of permeation of energy possessed by natural external force. Since the water permeability quality of such a natural external force permeation suppression membrane layer 9 is not subject to legal regulations, it is not fixed to the water impermeable base 13, and is not fixed to the sea side surface 29 of the riprap 5, for example ( only) is provided. That is, the natural external force permeation suppression membrane layer 9 is provided from the lower end of the riprap dyke 5 (the boundary between the riprap dyke 5 and the impermeable base 13 ) to the upper end of the riprap dyke 5 .

The lower end of the natural external force permeation suppression membrane layer 9 may be positioned slightly above the lower end of the rubble dyke 5 by being slightly separated from the lower end of the riprap dyke 13 (impermeable base 13). .

As a result, seawater enters from the natural external force permeation suppression membrane layer to the impermeable sheet 7 on the waste disposal site 3 side (land side), but the maximum value of the natural external force is reduced by the natural external force permeation suppression membrane layer 9. smaller than without For example, it is less than half, or less than 1/10.

The managed bank protection 1 shown in FIG. 1 is provided with a ground treatment crushed stone layer 23 , an intermediate protective crushed stone layer 25 and a covering protective crushed stone layer 27 . Two impervious sheets 7 are provided in the managed bank protection 1 shown in FIG. That is, an upper waterproof sheet 7A and a lower waterproof sheet 7B are provided.

The ground treatment crushed stone layer 23 covers the rubble embankment 5 on the waste disposal site 3 side (land side), and the lower layer impermeable sheet which is the first impermeable sheet of the two impermeable sheets 7 7B covers the ground treatment crushed stone layer 23, the intermediate protective crushed stone layer 25 covers the lower impermeable sheet 7B, and the upper impermeable sheet which is the second impermeable sheet of the two impermeable sheets 7 A sheet 7A covers the intermediate protective crushed stone layer 25, and a covering protective crushed stone layer 27 covers the upper waterproof sheet 7A.

The value of the thickness of the intermediate protective crushed stone layer 25 shown in FIG. 1 is smaller than the value of the thickness of the intermediate protective crushed stone layer 311 shown in FIG. For example, it is about 1/10.

Therefore, in the managed seawall 1 shown in FIG. Although it is applied to 7B, there is a possibility that the lower layer impermeable sheet 7B and the like may be lifted up by the natural external force of seawater passing through the rubble dyke 5 and the like.

However, in the managed revetment 1 shown in FIG. 1, the natural external force permeation suppression membrane layer 9 is provided, so even if the intermediate protective crushed stone layer 25 is thin, the impermeable sheet 7B and the like are prevented from being lifted. .

By the way, in the managed seawall 1 shown in FIG. 1, the natural external force permeation suppression membrane layer 9 may be impermeable.

The managed bank protection 1 shown in FIG. 1 will be described in more detail.

The cross-sectional shape of the rubble dyke 5 as a bank protection structure on a plane orthogonal to the horizontal direction is constructed with the cross-sectional shape and cross-sectional dimensions that are required both functionally, in combination, and structurally. For example, it is formed in a trapezoidal shape.

One oblique side of the trapezoid (the oblique side on the sea side) represents the riprap type inclined levee sea area slope 29, and the other oblique side of the trapezoid (the oblique side on the side of the waste disposal site 3) represents the riprap type inclined levee landfill area slope. 31.

The natural external force permeation suppression membrane layer 9 is in direct contact with the riprap type inclined levee sea area slope 29 and covers, for example, the entire surface of the riprap type inclined levee marine area slope 29 . Almost all of the membrane layer 9 for suppressing natural external force permeation is covered with the covering block 33 . The covering block 33 is in direct contact with the natural external force permeation suppressing membrane layer 9 .

The surface treatment crushed stone layer 23 is in direct contact with the slope 31 of the riprap type inclined levee disposal site area and covers the entire surface of the riprap type inclined levee area slope 31 . The lower impermeable sheet 7B covers the entire surface treatment crushed stone layer 23 and the vicinity of the surface treatment crushed stone layer 23 of the impermeable base 13 . The lower impermeable sheet 7B and the pretreated crushed stone layer 23 and the vicinity of the pretreated crushed stone layer 23 of the impermeable base 13 are in direct contact with each other.

The intermediate protective crushed stone layer 25 covers the entire lower impermeable sheet 7B and the vicinity of the lower impermeable sheet 7B of the impermeable base 13 . The intermediate protective crushed stone layer 25 and the lower impermeable sheet 7B and the vicinity of the lower impermeable sheet 7B of the impermeable improved base 13 are in direct contact with each other.

The upper waterproof sheet 7A covers the entire intermediate protective crushed stone layer 25 and the vicinity of the intermediate protective crushed stone layer 25 of the impermeable base 13 . The upper impermeable sheet 7A, the intermediate protective crushed stone layer 25, and the portion of the impermeable improved base 13 near the intermediate protective crushed stone layer 25 are in direct contact with each other.

The covering protective crushed stone layer 27 covers the entire upper impermeable sheet 7A and the vicinity of the impermeable substrate 13 near the upper impermeable sheet 7A. The covering protective crushed stone layer 27 and the upper impermeable sheet 7A and the portion of the impermeable improved base 13 near the upper impermeable sheet 7A are in direct contact with each other.

In addition, what is indicated by reference numeral 37 in FIG. 1 is the superstructure base concrete block, what is indicated by reference numeral 39 in FIG. 1 is the upper concrete, and what is indicated by reference numeral 41 in FIG. It is a riprap embankment.

Here, the operation of the managed bank protection 1 shown in FIG. 1 will be described. Seawater exists on the sea side in FIG. 1, and the natural external force (see arrows in FIG. 1) is applied to the membrane layer 9 for suppressing natural external force permeation. However, since the natural external force applied to the natural external force permeation suppression membrane layer 9 is weakened and passes through the rubble dyke 5, the value of the force (pressure) applied to the lower layer impermeable sheet 7B and the like becomes small. In addition, when the natural external force applied to the natural external force permeation suppressing membrane layer 9 is blocked by the natural external force permeation suppressing membrane layer 9, the value of the force (pressure) applied to the lower layer waterproof sheet 7B etc. becomes almost "0".

In addition, the waste and retained water discarded in the waste disposal site 3 are blocked by the impermeable sheet 7 and are prevented from leaking out to the sea side.

According to the managed seawall 1 shown in FIG. The natural external force applied to the impermeable sheet 7 can be reduced by allowing seawater to pass through the gap of . This eliminates the need to increase the thickness of the intermediate protective crushed stone layer 25 in order to prevent the impervious sheet 7 from floating, and the reduction in the volume of the waste disposal site 3 can be avoided as much as possible.

That is, the volume of the waste disposal site 3 is increased by the space 35 between the broken line shown in FIG. In addition, an increase in construction costs and an extension of the construction period can be avoided.

In addition, in the managed seawall 1, a seawater-impermeable membrane layer (a layer that artificially forms a seawater-impermeable surface) 9 is provided on the rubble dyke 5 on the sea side of the impermeable sheet 7, thereby It is also possible to eliminate the natural external force applied to the impermeable sheet 7 by allowing seawater to pass through the gaps between the riprap 5 . This further eliminates the need to increase the thickness of the intermediate protective crushed stone layer in order to prevent the impervious sheet 7 from floating, and further avoids a reduction in the volume of the waste disposal site 3 .

In the managed seawall 1 shown in FIG. 1, even if a natural external force is applied to the natural external force permeation suppressing membrane layer 9, the applied natural external force pushes the natural external force permeation suppressing membrane layer 9 against the rubble dyke 5. Therefore, the natural external force permeation suppressing membrane layer 9 does not float.

Moreover, according to the managed seawall 1 shown in FIG. Even after the rubble dyke 5 is installed, the natural external force permeation suppression membrane layer 9 can be easily installed.

Moreover, according to the managed bank protection 1 shown in FIG. As a result, even if the natural external force permeation suppressing membrane layer 9 is slightly damaged and seawater passes through the natural external force permeation suppressing membrane layer 9, the function of the natural external force permeation suppressing membrane layer 9 is maintained.

Next, the managed bank protection 1 shown in FIG. 2 will be described.

The managed seawall 1 shown in FIG. 2 differs from the managed seawall 1 shown in FIG. It is configured in the same manner, and has the same effect as the management type revetment 1 shown in FIG.

That is, the impermeable sheet 7 of the managed revetment 1 shown in FIG. there is In addition, the natural external force permeation suppression membrane layer 9 of the managed revetment 1 shown in FIG.

Further explaining, in the managed seawall 1 shown in FIG. In the vertical direction, the position of the upper end of the natural external force permeation suppression membrane layer 9 and the position of the upper end of the rubble dyke 5 coincide with each other.

The natural external force permeation suppression membrane layer 9 is made of a material that reduces the natural external force applied to the impermeable sheet 7 when seawater passes through the gaps between the rubble stones that make up the rubble dyke 5, and is water impermeable. It is composed of a vertical impermeable wall erected from the upper surface of the improved base 13, is not embedded in the impermeable base 13, and is provided from the upper surface of the impermeable base 13 to the upper end of the riprap 5. there is In addition, the lower end of the natural external force permeation suppression membrane layer 9 may be positioned slightly above the upper surface of the impermeable substrate 13 by being slightly separated from the impermeable substrate 13 .

For example, one natural external force permeation suppression membrane layer 9 is provided. Considering workability, sheet piles, iron plates, concrete plates, and bag formwork represented by Advance Form manufactured by Taiyo Kogyo Co., Ltd. (bag formwork Filling material such as solidified soil inside) can be listed.

In the managed seawall 1 shown in FIG. is As a result, the natural external force permeation suppressing membrane layer 9 is installed in a stable state.

Next, the managed bank protection 1 shown in FIG. 3 will be described.

The managed seawall 1 shown in FIG. 3 differs from the managed seawall 1 shown in FIG. It is configured in the same manner and has the same effect as the managed bank protection 1 shown in FIG.

That is, the natural external force permeation suppression membrane layer 9 of the managed revetment 1 shown in FIG.

To explain further, the membrane layer 9 for suppressing natural external force permeation is made of a material that reduces the natural external force applied to the impervious sheet 7 when seawater passes through the gaps between the rubble stones forming the rubble dyke 5. , is developed obliquely within the riprap dyke 5, and is provided from the upper surface of the impermeable base 13 to the upper end of the riprap dyke 5. In addition, the lower end of the natural external force permeation suppression membrane layer 9 may be positioned slightly above the upper surface of the impermeable substrate 13 by being slightly separated from the impermeable substrate 13 .

The membrane layer 9 for suppressing the permeation of natural external force of the managed revetment 1 shown in FIG. The permeation suppression membrane layer 9 may be inclined in the same posture as the slope 29 of the rubble-type inclined bank sea area.

As the natural external force permeation suppression membrane layer 9 shown in FIG. Bag forms represented by foams (the bag forms are filled with a filling material such as solidified soil) can be mentioned.

Next, the managed bank protection 1 shown in FIG. 4 will be described.

The managed seawall 1 shown in FIG. It differs from the managed revetment 1 shown in FIG. 1 in that it is not provided. It has the same effect as

That is, the natural external force permeation suppression membrane layer 9 of the managed revetment 1 shown in FIG. It is configured. As a result, seawater does not enter the waste disposal site 3 side (land side) of the membrane layer 9 for suppressing natural external force permeation.

Further, the managed bank protection 1 shown in FIG. 4 is provided with a ground treatment crushed stone layer 23 and a protective protective crushed stone layer 27, and only one impermeable sheet 7 is provided. The groundwork crushed stone layer 23 covers the rubble embankment 5 on the waste disposal site side (land side), the impermeable sheet 7 covers the groundwork crushed stone layer 23, and the covering protective crushed stone layer 27 covers the impermeable sheet 7. covering.

The natural external force permeation suppression membrane layer 9 of the managed revetment 1 shown in FIG. Therefore, as the impermeable membrane layer (natural external force permeation suppressing membrane layer) 9, a material having a water permeability quality of k=1.0×10 ⁻⁵ cm/s or less is adopted.

To explain further, the non-permeable membrane layer 9 is made of a material that eliminates the natural external force applied to the impermeable sheet 7 by passing through the gaps between the rubble stones forming the rubble dyke 5, and the impermeable base 13 It has a water-impermeable base fixing portion (horizontally developed portion) 43 fixed to the base. It should be noted that the length of the water-impermeable base fixing portion in the inside and outside directions is subject to legal regulations, so the length must be at least 5 m.

The controlled seawall 1 shown in FIG. It is different from the managed revetment 1 shown in FIG. 1 has the same effect.

More specifically, in the managed seawall 1 shown in FIG. C.D.M.) 13 (the lower end of the sheet pile reaches a predetermined depth in the impermeable base 13). In other words, the natural external force permeation suppression membrane layer 9 is embedded in the impermeable stratum (impermeability improving base) 13 to a predetermined depth. The predetermined depth is set at least 2.5 m or more because it is subject to legal regulations. Even if the vertical impermeable wall is made of a material other than the sheet pile, the lower end of the vertical impermeable wall penetrates into the impermeable base to a predetermined depth.

Like the managed revetment 1 shown in FIG. The vertical impermeable wall is integrated with the impermeable improved base 13 by being indented. This eliminates displacement of the vertical impermeable wall with respect to the impermeability improving base 13 when a natural external force is applied to the vertical impermeable wall, and eliminates a change in the attitude of the vertical impermeable wall with respect to the impermeability improving base. In addition, the water impermeability of the membrane layer 9 for suppressing the permeation of natural external force is improved.

The managed seawall 1 shown in FIG. 3 is different from the managed revetment 1 shown in FIG. 1 has the same effect.

More specifically, in the managed seawall 1 shown in FIG. 6, the impermeable membrane layer 9 is fixed to the impermeable stratum 13 for a length of 5 m or longer (the impermeable base fixing portion 43 is provided). In addition, the impermeable membrane layer 9 has good water impermeability.

According to the managed seawall 1 shown in FIGS. 4 to 6, the natural external force permeation suppression membrane layer 9 is a material that eliminates the natural external force applied to the impermeable sheet 7 (material that blocks seawater; seawater impermeable membrane layer). , the seawater-impermeable membrane layer 9 plays the role of a water shield. As a result, one layer (one sheet) of the impermeable sheet 7 can be provided on the waste disposal site 3 side. Moreover, the volume of the waste disposal site 3 can be further increased.

1 Controlled revetment 3 Waste disposal site 5 Rubble embankment 7, 7A, 7B Impervious sheet 9 Membrane layer for suppressing natural external force permeation 13 Impermeability improvement base 23 Crushed stone layer for ground treatment 25 Intermediate protective crushed stone layer 27 Covered protective crushed stone layer

Claims (6)

a riprap embankment built on an impermeable foundation; and
a waterproof sheet provided on the rubble dyke;
a natural external force permeation suppression membrane layer provided on the riprap bank on the sea side of the impermeable sheet;
Management type bank protection characterized by having. The managed seawall according to claim 1,
The impermeable sheet covers the rubble embankment on the waste disposal site side,
The managed seawall, wherein the natural external force permeation suppression membrane layer covers the rubble dyke on the sea side. The managed seawall according to claim 1,
The impermeable sheet covers the rubble embankment on the waste disposal site side,
The managed revetment, wherein the natural external force permeation suppression membrane layer is installed within the rubble embankment. The managed seawall according to claim 3,
A managed revetment, wherein the natural external force permeation suppression membrane layer is composed of a vertical impermeable wall. The managed seawall according to claim 2 or claim 3,
The natural external force permeation suppression membrane layer is made of a material that reduces the natural external force applied to the impermeable sheet when seawater passes through the gaps between the rubble stones that constitute the rubble dyke,
The ground treatment crushed stone layer, the intermediate protective crushed stone layer, and the covering protective crushed stone layer are provided, and two waterproof sheets are provided,
The groundwork crushed stone layer covers the rubble embankment on the waste disposal site side, and the first of the two water-shielding sheets covers the groundwork crushed stone layer, An intermediate protective crushed stone layer covers the first impermeable sheet, a second impermeable sheet of the two impermeable sheets covers the intermediate protective crushed stone layer, and the coated protective crushed stone A controlled revetment, wherein a layer covers the second impermeable sheet. The managed seawall according to claim 2 or claim 3,
The natural external force permeation suppression membrane layer is made of a material that eliminates the natural external force applied to the impermeable sheet by passing through the gaps between the rubble stones that constitute the rubble dyke,
It comprises a surface treatment crushed stone layer and a covering protective crushed stone layer, and is provided with one waterproof sheet,
The surface treatment crushed stone layer covers the rubble embankment on the waste disposal site side, the impermeable sheet covers the surface treatment crushed stone layer, and the covering protective crushed stone layer covers the impermeable sheet. Management type revetment characterized by this.

Images