JP3935591B2 - Lightweight embankment structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an embankment structure constructed as embankment such as roads and railways, back embankment such as retaining walls and abutments.
[0002]
[Prior art]
When constructing various structures such as roads and railways at a predetermined height, conventionally, earth and sand such as mountain sand is easily piled up on an existing ground to construct an embankment structure.
[0003]
By the way, in the case of constructing a road with a banking structure in a soft ground such as a wetland or a lake, there is a concern that the load of the banking structure may adversely affect the existing ground. Specifically, when an excessive loading load due to embankment acts on the existing ground, the existing ground is consolidated in the direction of gravity by this load, and ground subsidence occurs. In addition, a so-called lateral flow phenomenon occurs in which the ground flows in a direction perpendicular to the road direction (road side).
[0004]
Therefore, when building roads in soft ground areas, as a measure to prevent landform change due to ground subsidence or lateral flow, sand mat construction method that lays sand between existing ground and embankment, below the planned embankment Sand drain construction method to place sand piles, pre-load construction method to construct the original embankment structure after preliminarily embedding in the planned embankment and forcibly promote the settlement of the existing ground using the load Numerous methods have been developed.
[0005]
In recent years, a construction method (EPS construction method) using a polystyrene foam material (polystyrene foam material) as a material for embankment has been introduced and is actually being constructed in various parts of the country. In the EPS method, the core part of the embankment structure is formed by stacking block-shaped expanded polystyrene materials according to certain rules, and the outer surface part is covered with earth and sand to construct the embankment structure. is there.
[0006]
Furthermore, a construction method has been developed for constructing a banking structure using a banking material that is lightened by mixing foam beads made of foamed polystyrene, foamed polypropylene, or the like with earth and sand.
[0007]
[Problems to be solved by the invention]
In the case of the sand mat method and sand drain method, the main purpose is to discharge the groundwater that exists in the gaps between the soil particles that make up the existing ground to the outside by the load of the embankment structure, completely preventing the ground subsidence itself. The actual situation is not possible.
[0008]
In addition, in the case of the preload method, it often takes 10 to 20 years or more to completely drain the groundwater existing in the gaps between the soil particles constituting the existing ground. Since land subsidence is continuously progressing, it cannot be prevented only by suppressing land subsidence.
[0009]
Furthermore, in the case of the EPS method, a special locking tool such as a ground anchor is required as a means for fixing the expanded polystyrene material to the ground, and a special connecting member is required to connect the expanded polystyrene materials, Construction may become complicated and the construction period may be prolonged. Also, the construction cost is high compared to other conventional methods.
[0010]
On the other hand, in order to reduce the thickness of concrete structures such as culvert boxes, retaining walls, and abutments, an embankment structure is also constructed in close contact with the wall surfaces of these concrete structures. The above construction method is applied also to the embankment structure in this case, and the same problems are inherent.
[0011]
Therefore, the problem to be solved by the present invention is to provide a lightweight embankment structure that is effective in preventing ground subsidence and lateral flow of the ground and slimming the concrete structure, and has excellent durability. It is in.
[0012]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the lightweight embankment structure of the present invention is a synthetic resin solid material formed by thermally melting and solidifying a foamed synthetic resin with respect to a strut driven into the ground as a ground fixing material for preventing lifting . The block body and the spacer are alternately passed through and laminated, and a panel material locked to the support column via a support member is erected on the side of the block body and the foamed mortar around the stack space of the block body and its periphery. or characterized in that constructed by the filling of the urethane foam.
[0013]
Here, the synthetic resin solid material includes a lump obtained by crushing an ingot obtained by melting and solidifying a foamed synthetic resin, or a lump formed into a lump in the course of solidification, and a block formed after solidification. . In the case of a lump obtained by crushing an ingot, the size of the lump can be adjusted by changing the degree of crushing. Moreover, when laminating synthetic resin solids on the ground as will be described later, in order to increase the efficiency of the laminating work and ensure stability when laminated on the ground, the shape of the synthetic resin solids is It is desirable to use a block body formed into a fixed shape such as a rectangular parallelepiped, a cube, or a plate. As other embankment materials to be combined with these synthetic resin solid bodies or blocks, earth and sand, foamed mortar, urethane foam and the like can be used.
[0014]
When using a combination of synthetic resin solids and earth and sand, a mixture of synthetic resin solids and earth and sand is piled up on the ground to form an embankment structure, or an aggregate layer of synthetic resin solids and earth and sand Layers can be alternately stacked on the ground to form a banking structure, or a block of synthetic resin solids stacked on the ground can be covered with earth and sand to form a banking structure. In addition, when using a combination of synthetic resin solids, foamed mortar, and urethane foam, the blocks of synthetic resin solids are laminated on the ground with or without a gap, and this laminated space and laminated outside or laminated Only the exterior can be filled with foamed mortar and / or urethane foam to form an embankment structure.
[0015]
The inside of the synthetic resin solid material obtained by melting and solidifying the foamed synthetic resin contains a number of voids formed by the expansion of the gas contained in the foamed synthetic resin foam cell during heating. Therefore, the specific gravity of the synthetic resin solid material is smaller than 2.7 which is the average specific gravity of earth and sand. In addition, since the synthetic resin solid material is formed by heat melting and solidifying a foamed synthetic resin that is originally excellent in shape retention, it has a high strength equivalent to that of soft rock. Therefore, the specific gravity of the embankment material combined with synthetic resin solids and earth and sand is smaller than the specific gravity of earth and sand, and if the embankment structure is constructed with this embankment material, the entire embankment structure will be reduced in weight and strength, Generation of ground subsidence and lateral flow of the ground can be prevented, and further, when the embankment structure is constructed in close contact with the wall surface of the concrete structure, the concrete structure can be slimmed. In addition, if the embankment structure is constructed by combining synthetic resin solids, foamed mortar, and foamed urethane, it is cheaper and economically lighter than when a lightweight embankment structure is constructed using only conventional foamed mortar or urethane foam. An embankment structure can be constructed.
[0016]
Further, the synthetic resin solid material does not generate corrosion, and is excellent in durability and economy. Furthermore, since the voids contained in the synthetic resin solids are independent structures, the initial state is maintained for a long time after construction without absorbing moisture such as rainwater or groundwater and causing an increase in weight. be able to.
[0017]
The melting temperature when the foamed synthetic resin is melted and solidified to obtain a synthetic resin solid is preferably 80 to 300 ° C. When the melting temperature is lower than 80 ° C., the voids contained in the synthetic resin solids increase, and thus the strength tends to decrease. When the melting temperature is higher than 300 ° C., the voids decrease and the apparent specific gravity increases, so that the lightweight embankment material. As a function is lost. Synthetic resin solids that are melted and solidified at 80-300 ° C have a good balance between apparent specific gravity and strength, are lightweight and high in strength, and have excellent functions such as ground subsidence prevention and durability. An embankment structure can be constructed. Moreover, if the apparent specific gravity of a synthetic resin solid substance is 0.4-1.0, the dispersibility in the case of mixing with earth and sand will improve, and a uniform property mixture can be obtained.
[0018]
When a mixture of synthetic resin solids and earth and sand is used as embankment material, a strong binding force between the synthetic resin solids and earth and sand is obtained by setting the blending ratio of the synthetic resin solids in the mixture to 25 to 75% by weight. Is obtained. When the blending ratio of the synthetic resin solids is less than 25% by weight, the function as a lightweight embankment material is lowered because it approaches the properties of the earth and sand, and the possibility of inducing ground subsidence increases. Since the bond strength of the mixture is reduced, stability and durability when a long time has elapsed after construction are reduced.
[0019]
As the foamed synthetic resin which is a raw material of the synthetic resin solid used in the present invention, foamed polystyrene is suitable. Synthetic resin solids having a specific gravity of about 0.7 and a uniaxial compressive strength of about 200 kgf / cm ² can be obtained by thermally melting and solidifying the expanded polystyrene. Therefore, by combining this synthetic resin solid material with earth and sand, foamed mortar, foamed urethane, or the like to form a banking material, the entire banking structure can be reduced in weight and strength.
[0020]
In this case, by using foamed polystyrene, which is a used waste material, as a raw material, it is possible to significantly reduce costs, and to contribute to prevention of environmental pollution through effective use of industrial waste.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory view showing a manufacturing process of a synthetic resin solid constituting a lightweight embankment structure, and FIG. 2 is a longitudinal sectional view showing a lightweight embankment structure according to the first embodiment.
[0022]
First, with reference to FIG. 1, the manufacturing method of the lump (henceforth lump solid) 12 of the synthetic resin solid used as embankment material in this embodiment is demonstrated. As shown in the figure, the foamed polystyrene 11 as waste is melted and solidified to form an ingot 16, and the ingot 16 is crushed or formed into a lump in the solidification process. A solid 12 is obtained. The bulk solid 12 has a structure including a large number of voids 17 (see FIG. 2) formed when the gas contained in the foamed cell of the original foamed polystyrene 11 expands by heating. Yes.
[0023]
In the present embodiment, a bulk solid 12 having an apparent specific gravity of about 0.7 and a uniaxial compressive strength of about 200 kgf / cm ² is obtained by setting the melting temperature of the expanded polystyrene 11 to 80 to 300 ° C. The mixture 14 of the block solid 12 and earth and sand 13 has high strength and is lighter than the earth and sand 13.
[0024]
The lightweight embankment structure 10 in FIG. 2 is constructed by stacking a mixture 14 of the block solid 12 and earth and sand 13 on a ground 15.
[0025]
Thus, by using the mixture 14 of the lump solid material 12 and the earth and sand 13 as the embankment material, even if the lightweight embankment structure 10 is lightened and the ground 15 is soft, the ground 15 is subsidized or the ground 15 side is reduced. No side flow occurs. In addition, since the massive solid material 12 does not corrode even under a high moisture condition, the lightweight embankment structure 10 has excellent durability, and the initial state can be maintained for a long period of time.
[0026]
Moreover, in this embodiment, since the foamed polystyrene 11 which is a used waste material is used as the foamed synthetic resin that is a raw material of the bulk solid 12, the cost can be greatly reduced, and industrial waste can be reduced. It can contribute to prevention of environmental pollution through effective utilization.
[0027]
Furthermore, in this embodiment, when the apparent specific gravity of the massive solid 12 is set to 0.4 to 1.0, the dispersibility when mixed with the earth and sand 13 is good, the mixed state becomes uniform, and the homogeneous lightweight embankment. The structure 10 could be constructed.
[0028]
Moreover, in this embodiment, when the blending ratio of the massive solids 12 in the mixture 14 of the earth and sand 13 and the massive solids 12 is 50% by weight, a strong binding force can be obtained, and the weight is excellent in durability. The embankment structure 10 was able to be constructed.
[0029]
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a longitudinal sectional view showing a lightweight embankment structure according to the second embodiment.
[0030]
The lightweight embankment structure 20 of the present embodiment is constructed by alternately stacking the accumulation layers 21 and the earth and sand layers 22 of the massive solid bodies 12 on the ground 15. By setting it as such a laminated structure, the effort which mixes a lump solid substance and earth and sand like the case of 1st Embodiment can be saved. Moreover, since the accumulation | aggregation layer 21 is formed with the block solid 12 which uses a foaming synthetic resin as a raw material, intensity | strength is high, corrosion does not generate | occur | produce and it is excellent also in durability. Since the light weight embankment structure 20 in this embodiment also becomes lighter than the embankment structure formed only with earth and sand, ground subsidence and lateral flow of the ground do not occur after construction.
[0031]
Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 4 is a longitudinal sectional view showing a lightweight embankment structure according to the third embodiment.
[0032]
The lightweight embankment structure 30 of the present embodiment is constructed by laminating block bodies 31 obtained by molding the ingot 16 shown in FIG. 1 into a rectangular parallelepiped shape on the ground 15 and covering the outside of these block bodies 31 with earth and sand 32. Is. By adopting such a configuration, the main part is a block body 31 having a specific gravity smaller than that of the earth and sand, so that the overall weight is lighter than when only the earth and sand are constructed. There is no flow.
[0033]
In the present embodiment, the block body 31 has a structure including a large number of voids 33, so that it is lightweight and has high strength, does not cause corrosion, and is excellent in durability. Moreover, since the block body 31 is a rectangular parallelepiped shape, the workability | operativity at the time of laminating | stacking on the ground 15 is favorable, and the stability after lamination | stacking is also excellent. The block body 31 is not limited to this shape, and various shapes can be used according to the conditions at the construction site. For example, a cubic block body 34 as shown in FIG. 1 is used. You can also.
[0034]
Next, a fourth embodiment of the present invention will be described with reference to FIGS. FIG. 5 is a longitudinal sectional view showing a lightweight embankment structure according to the fourth embodiment, and FIG. 6 is a partially enlarged view of FIG.
[0035]
The light weight embankment structure 40 of this embodiment is constructed as a widening embankment on the side of the existing embankment structure 41. The lightweight embankment structure 40 is made by laminating blocks 42 and spacers 44 made of a synthetic resin solid material alternately on a support 43 driven into the ground 15 as a ground fixing material for preventing lifting. The panel material 45 is erected and the foamed mortar (or foamed urethane) 46 is filled in the laminated space of the block bodies 42 and the periphery thereof. In this case, the column 43 is connected by a bolt / nut portion 43a, and the panel material 45 is locked to the column 43 via a support member 47 for fixing the panel. It is also possible to stack the block bodies 42 without using the spacers 44 and fill the periphery with foamed mortar (or foamed urethane) 46.
[0036]
By adopting such a configuration, the light weight embankment structure 40 has a block 42 that is cheaper than the foam mortar (or urethane foam) 46 as a main part, and the foam mortar (or foam urethane) 46 around the laminated space and the periphery thereof. Because it has a filled structure, it is cheaper and more economical than the conventional construction of lightweight embankment structures using only foamed mortar (or urethane foam), and the overall weight is lighter than that of construction using only earth and sand. Therefore, after construction, ground subsidence and lateral flow of the ground do not occur. Moreover, the land area can be reduced by this construction method.
[0037]
Next, a fifth embodiment of the present invention will be described with reference to FIG. 7A to 7C are longitudinal sectional views showing the fifth embodiment. This embodiment is an example in which a lightweight embankment structure is constructed on the back surface of an abutment.
[0038]
A lightweight embankment structure 50 a shown in FIG. 5A is constructed by stacking a mixture 14 of massive solids 12 and earth and sand 13 on the back surface of an abutment 51. Moreover, the light weight embankment structure 50b of the same figure (b) is constructed | assembled by laminating | stacking the accumulation layer 52 and the earth-and-sand layer 53 of the block solid body 12 on the back surface of the abutment 51 alternately. Furthermore, the lightweight embankment structure 50c in FIG. 5C is constructed by laminating a block body 54, which is a synthetic resin solid material, on the back surface of the abutment 51 and filling the surrounding area with the earth and sand 13.
[0039]
The massive solid body 12 and the block body 54 are formed by thermally melting and solidifying foamed polystyrene, and are lighter than earth and sand, so that the earth pressure on the back of the abutment 51 is reduced, and ground subsidence and lateral flow of the ground are performed. Thus, the initial state can be maintained for a long time. Moreover, since the back surface earth pressure is reduced, the abutment 51 can be slimmed down, which is an inexpensive and economical construction method. In addition, the lightweight embankment structure for slimming of a retaining wall can also be constructed | assembled by the same construction method as this embodiment.
[0040]
Next, a sixth embodiment of the present invention will be described with reference to FIG. 8A to 8C are longitudinal sectional views showing the sixth embodiment. This embodiment is an example in which a lightweight embankment structure is constructed on the side and above the box culvert.
[0041]
A light-weight embankment structure 60 a shown in FIG. 5A is constructed by stacking a mixture 14 of massive solids 12 and earth and sand 13 on the side and upper side of the box culvert 61. Moreover, the lightweight embankment structure 60b of the same figure (b) is constructed by laminating | stacking the accumulation layer 62 and the earth-and-sand layer 63 of the block solid body 12 on the side and upper side of the box culvert 61 alternately. . Furthermore, the lightweight embankment structure 60c shown in FIG. 5C is constructed by laminating a block body 64, which is a synthetic resin solid material, on the side and upper side of the box culvert 61 and filling the periphery with the sand 13. Is.
[0042]
The massive solid body 12 and the block body 64 are formed by thermally melting and solidifying foamed polystyrene, and are lighter than earth and sand, so that the side earth pressure of the box culvert 61 is reduced, and the ground subsidence and the side of the ground It is possible to maintain the initial state for a long period of time without causing flow. Further, the reduction of the side earth pressure makes it possible to reduce the design load resistance, thereby making it possible to slim the concrete structure body.
[0043]
The lightweight embankment structure according to the present invention is not limited to these embodiments, but is used for construction of general roads such as highways and general national roads or railway construction, as well as for plane crossing roads and plane crossing railways. It can also be used on the body and roadbed.
[0044]
【The invention's effect】
According to the present invention, the following effects can be obtained.
[0045]
(1) By constructing the entire embankment structure with the embankment material containing the synthetic resin solid material obtained by heat melting and solidifying the foamed synthetic resin, the entire embankment structure is reduced in weight and strength. It is possible to prevent the generation of the direction flow. Furthermore, when it is used for reinforcing a concrete structure, the concrete structure can be slimmed.
[0046]
(2) Synthetic resin solids are not corroded and are excellent in durability and economy. Furthermore, since the voids contained in the synthetic resin solids are independent structures, The initial state can be maintained for a long period of time without absorbing water such as groundwater and causing an increase in weight.
[0047]
(3) If the embankment structure is constructed by combining synthetic resin solids, foamed mortar, and foamed urethane, it is cheaper and more economical than the construction of a lightweight embankment structure using only conventional foamed mortar or foamed urethane. A lightweight embankment structure can be constructed.
[0048]
(4) By using a synthetic resin solid material obtained by hot-melting and solidifying a foamed synthetic resin at 80 to 300 ° C., the balance between the apparent specific gravity and strength of the synthetic resin solid material becomes good, light weight and high strength. In addition, it is possible to construct a light-weight embankment structure that is excellent in prevention functions such as land subsidence and durability.
[0049]
(5) By using a synthetic resin solid having an apparent specific gravity of 0.4 to 1.0, dispersibility when mixed with earth and sand is improved, and a uniform property mixture can be obtained. A lightweight embankment structure with excellent properties can be constructed.
[0050]
(6) By setting the blending ratio of the synthetic resin solids in the mixture of the synthetic resin solids and earth and sand to 25 to 75% by weight, the weight can be reduced and a strong bonding force between the massive solids and earth and sand can be obtained. It is possible to construct a lightweight embankment structure that is excellent in strength and durability and can maintain the initial state over a long period of time.
[0051]
(7) By using foamed polystyrene as the foamed synthetic resin of the raw material, a synthetic resin solid having a particularly good balance between apparent specific gravity and strength can be obtained.
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an explanatory view showing a production process of a synthetic resin solid material constituting a lightweight embankment structure.
FIG. 2 is a longitudinal sectional view showing a lightweight embankment structure according to the first embodiment.
FIG. 3 is a longitudinal sectional view showing a lightweight embankment structure according to a second embodiment.
FIG. 4 is a longitudinal sectional view showing a lightweight embankment structure according to a third embodiment.
FIG. 5 is a longitudinal sectional view showing a lightweight embankment structure according to a fourth embodiment.
6 is a partially enlarged view of FIG. 5;
FIG. 7 is a longitudinal sectional view showing a lightweight embankment structure according to a fifth embodiment.
FIG. 8 is a longitudinal sectional view showing a lightweight embankment structure according to a sixth embodiment.
[Explanation of symbols]
10, 20, 30, 40, 50a to 50c, 60a to 60c Lightweight embankment structure 11 Expanded polystyrene 12 Lumped solids 13, 32 Earth and sand 14 Mixture 15 Ground 16 Ingot 17, 33 Air gaps 21, 52, 62 Accumulated layers 22, 53 , 63 Sediment layer 31, 34, 42, 54, 64 Block body 41 Embankment structure 43 Column 43a Bolt / nut portion 44 Spacer 45 Panel material 46 Foamed mortar (foamed urethane)
47 Support member 51 Abutment 61 Box culvert

Claims (4)

Blocks and spacers that are synthetic resin solids formed by hot-melting and solidifying foam synthetic resin against the struts that have been driven into the ground as a ground fixing material for preventing lifting , are laminated by alternately passing blocks and spacers. and characterized in that through the support member laterally provided upright locked panels material to the struts, it was constructed by the filling of the foam mortar or foamed urethane around the stack space of the block body A lightweight embankment structure. The synthetic resin solids, foamed synthetic resin hot melt at 80 to 300 ° C., in which solidified claim 1 Symbol mounting lightweight embankment structures. The lightweight embankment structure according to claim 1 or 2, wherein the apparent specific gravity of the synthetic resin solid is 0.4 to 1.0. The lightweight embankment structure according to any one of claims 1 to 3, wherein the synthetic resin solid material is obtained by thermally melting and solidifying foamed polystyrene.

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