JPH0721189B2 - Foam block for civil engineering foundation - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a foam block for civil engineering foundation reinforced with at least one of a fiber and a fabric.

More specifically, a foam made of high-rigidity resin is reinforced with at least one of specific composite fiber and composite yarn,
The present invention relates to a foam block for civil engineering foundation having good dimensional stability, compressive strength, tensile strength and the like.

[Prior Art] In recent years, as an ultra-light embankment method on soft ground or uneven land, styrofoam rectangular blocks are stacked vertically and horizontally to construct a styrofoam embankment, on which bridges, airfields, paved roads, railways, etc. are constructed. The so-called EPS civil engineering method is being developed.

Such a construction method has advantages such as excellent shape retention and light weight of the foam block that can prevent ground subsidence and enables inexpensive and quick construction.It has already been put to practical use in Europe, and even in Japan. It has come to be constructed.

As such a proposal, there is one in which foam blocks made of a synthetic resin are arranged to form a foundation, but those using the foam block alone do not have sufficient dimensional stability and mechanical performance of the foam block itself, It is not preferable because it causes deformation and fracture due to complicated and extreme compression and tensile action due to external stress, which causes ground subsidence and ground flow.

To solve this problem, Japanese Patent Laid-Open Nos. 62-45801 and 6-61
Japanese Patent Laid-Open No. 3-47426 discloses a proposal to strengthen or strengthen a foam block by disposing or mixing a reinforcing member such as a wire mesh or a net. However, there have been many ideas for reinforcing foam such as Styrofoam with wire mesh or net, but since the reinforcing member and the foam are not bonded and integrated sufficiently, the foam and the reinforcing member are not affected by external stress. It does not have a structure that causes a slip phenomenon, and both are integrated and simultaneously take the stress. Therefore, it does not have an effective improvement effect against problems such as deformation and destruction.

[Problems to be Solved by the Invention] It is an object of the present invention to solve the above problems and provide a foam block for civil engineering foundation in which ground subsidence or ground flow is unlikely to occur.

[Means for Solving the Problems] In order to achieve the above object, the present invention has the following configuration.

That is, the foam block for civil engineering foundation according to the present invention, the flexural modulus of the non-foamed resin alone is made of a resin having a high rigidity of 150 kg / mm ² or more, and the foamed resin is an intrafiber resin. In addition, it is characterized by being reinforced by at least one of a composite fiber and a composite yarn which have an adhesive component and a fibrous component and are sufficiently stretched in the axial direction of the fiber.

Alternatively, it is also a foam block for civil engineering foundation whose surface and / or interior is reinforced by mixing at least one of a composite fiber and a composite yarn, and the composite one component is thermally deformed or melted by heat treatment. It is an adhesive component and is characterized in that other components are present as fibrous components to reinforce the foam resin, and the surface of the fabric is composed of at least one of the composite fiber and the composite yarn. And a foam block for civil engineering foundation, at least one of which is reinforced, wherein the composite one component is thermally deformed or melted by heat treatment to become an adhesive component, and the other component exists as a fibrous component and foams. It is characterized by being reinforced with a body resin, and further, when at least one of the composite fiber and the composite yarn is mixed, a small amount of the composite fiber and the composite yarn is contained. The configured fabric by one Kutomo, a surface and inside of at least one of enhanced the civil engineering foundation for foam blocks, said plurality coalescence components by heat treatment becomes thermally deformed or melted and adhesive component,
It is characterized in that other components are present as fibrous components to reinforce the foam resin.

In the foam block for civil engineering foundation of the present invention, preferably, the foam resin is a polymer containing a styrene monomer unit, and the adhesive component in the composite fiber is foamed. It is characterized in that it is a polymer containing the same monomer unit as the body resin, and at least one of the composite fiber and the composite yarn,
It is characterized by being a core-sheath type fiber,
In such a core-sheath type composite fiber structure, a multi-core sheath type fiber is preferable.

[Operation] As described in the section of the prior art, the use of a synthetic resin foam as a foam block for civil engineering foundation, a wire mesh,
It is known to reinforce the foam with a net or the like. However, such foam has been problematic in that it has poor dimensional stability and mechanical performance as a foam block for civil engineering foundations. The reason is that the foam and the reinforcing material cannot be sufficiently bonded and integrated, and an effective reinforcing structure has not been obtained.

Therefore, the present inventors intend to reinforce a specific foam made of a high-rigidity resin by using a specific composite fiber composed of a plurality of components or by using a cloth composed of the specific composite fiber. Solves this problem.

The present invention, at least one component has a high fiber strength sufficiently stretched in the fiber axis direction, and the other at least one component is easily and sufficiently thermally deformed under heat treatment temperature conditions, preferably foaming temperature conditions. A specific composite fiber composed of a component capable of melting or a cloth composed of the specific composite fiber (hereinafter referred to as "composite fiber / same cloth") is mixed with a foam resin composed of a specific high rigidity resin, This is achieved by using an integrated adhesive structure. Here, the heat treatment is pressure contact with a heating surface such as a heating press,
This means that the foam resin and the cloth are integrated by at least one of pressure bonding and adhesion. Of course, it is particularly preferable to simultaneously perform the foaming treatment at this temperature.

That is, at least one component of the composite fiber in the composite fiber and the cloth causes thermal deformation or melting by mixing the composite fiber and the cloth having such characteristics with a specific foam resin and then performing heat treatment. , The adhesive component is changed, and is preferably united by foaming energy to be bonded and integrated with the foam resin, and at least one other component remains as a fibrous one, against external stress such as bending and twisting, This is a structure in which the foam resin and the composite fiber / fabric simultaneously receive stress. By the mechanism of such reinforcement, the foam block for civil engineering foundation of the present invention can be a foam block for civil engineering foundation that is not easily deformed or destroyed by external stress, and a foundation material that is unlikely to cause ground subsidence or ground flow. Can be provided.

That is, the foam block for civil engineering foundation of the present invention is composed of two parts. One is a foam resin portion corresponding to the matrix portion of the foam resin, and the other is a composite fiber portion that reinforces the foam resin portion. The composite fiber portion is further divided into an adhesive component (A) for achieving adhesive integration with the foam resin and a fibrous component (B) for improving mechanical performance.

As the foam resin portion applied to the present invention, a foam resin of a highly rigid synthetic resin having excellent deformation resistance is used. In other words, the flexural modulus of the non-foamed resin alone is 150 kg /
Those with a rigidity of mm ² or more are preferable, especially 200 kg / m
Those having a rigidity of m ² or more are preferably used. This flexural modulus is measured by the ASTM-D790 method. Such high-rigidity resins include polystyrene, styrene / ethylene copolymers, acrylonitrile / styrene copolymers, ABS resins and the like, and are used as foams of these resins.

The component B in the conjugate fiber portion used in the present invention is a component that is sufficiently stretched in the fiber axis direction to have high orientation and high strength, and has extremely little strength deterioration due to heat during heat treatment, It is preferably applied that does not easily deteriorate even if it is buried in the soil for a long time. That is, the fiber strength in the B component unit is at least 2 g / d or more, and in particular,
It is preferably 3 g / d or more. For example, polyesters typified by polyethylene terephthalate, polyamides typified by nylon 6, nylon 66, polyarylate, polyacrylonitrile, polypropylene and copolymer modified products thereof, or a mixture of other components can be used. A polymer having spinnability can be applied. From these polymers, one or more polymers are used depending on the combination with the foam resin and the component A, the heat treatment temperature, and the environment in which they are used.

On the other hand, it is important that the component A, which contributes to the adhesive integration with the foam resin as an adhesive component, is one that causes thermal deformation or melting by heat treatment, and further satisfies the following or Is preferred.

That is, it is a polymer containing the same monomer units as the foam resin, is a polymer having good adhesion and compatibility with the foam resin, in particular, among them, preferred, but the same as the foam resin Even if it does not contain a monomer unit, due to thermal deformation or melting during heat (foaming) treatment, high frictional force or anchor effect acts on the foam resin component, and the fibers come out of the foam resin. The present invention can be sufficiently achieved as long as it can prevent slippage and slippage. Further, the combination of the A component and the B component may be the same component type polymers or different component type polymers.

The form of the composite fiber used in the present invention is a form such as a core-sheath type fiber, a bimetal type fiber, a multi-layer bonding type fiber, a radial multi-layer type fiber, etc. Among them, many core components are contained in the sheath component. Since the multicore-sheath type composite fiber, which is a structural fiber, has an adhesive component interposed between the multicores, the adhesive integration with the foam resin becomes better, and it is particularly preferably used. That is, it is represented by, for example, polymer array fibers, mixed spun fibers, and the like.

Further, in the above description, the case of the conjugate fiber obtained by the composite spinning has been described, but the present invention is not limited to the case of using such a conjugate fiber, and the core component or the sheath component described above is used. A mixed yarn such as a fibrous component, or a fiber made of a polymer described and explained as the A component and the B component, or a composite yarn such as a mixed twisted yarn may be used. That is, in the present invention, a fiber or yarn composed of component A and B
It is also possible to use a composite yarn using a combination of fibers or yarns composed of components.

Further, the reinforcing means according to the present invention is not limited to a fibrous or thread-shaped reinforcing means, but a cloth composed of at least one of the above-mentioned composite fiber and composite yarn is disposed in a foam resin for reinforcement. Is also included. In this case, the arrangement method of the foam resin (P) and the cloth (H) is
P / H / P, H / P / H, P / H / P / H or P / H / P / H / P are arranged and used.

Needless to say, the above-mentioned reinforcement by the fiber or thread and the reinforcement by the cloth may be used together. In this case, the reinforcing effect is extremely large, which is a preferable method. As such a cloth, any one of woven fabric, knitted fabric, non-woven fabric, reticulated sheet, or the like, a composite thereof, or a mixture thereof is used.

Further, in the present invention, there is no problem even if a reinforcing material such as a metal net or various cloths is used together with the above-mentioned composite fiber portion.

When the foam block for civil engineering foundation of the present invention is reinforced with fibrous or thread-like ones, a large number of reinforcing fibers are dispersed in the foam resin, or alternatively, it is reinforced with the above-mentioned cloth. In the case of the above-mentioned structure, the reinforcing fibers are present in the form of a cloth on the inside or the outside surface of the foam resin, and the reinforcement is made by using at least one of the fibers and yarns and the cloth. Both of these two types of structures will appear when the above is aimed at.

Further, in the present invention, the fiber length of the conjugate fiber may be any form of a long fiber (filament), a short fiber (staple) or an extremely short fiber (whisker).

In the present invention, the method for producing the foam block for civil engineering foundation is not particularly limited and may be produced by any method, but if one example of the preferable method is given, it is commercially available as a foam resin. Using expandable polystyrene beads, the core component is polyethylene terephthalate and the sheath component is a multi-core sheath type composite fiber composed of a copolymer of styrene and acrylic ester. The primary foaming is performed by spraying, and the primary expanded beads and the multi-core sheath type composite fiber are jetted from separate ejectors into a molding die having a part of the openings to be mixed and filled. Then, steam is blown into the molding die for secondary foaming and the sheath component of the multi-core sheath type composite fiber, which is a low heat-deformable component, is thermally deformed, and the foam resin component is bonded and integrated to achieve the civil engineering foundation. Foam blocks can be produced. Such foam blocks for civil engineering foundations are stacked vertically and horizontally and used as a foundation material for various structures.

[Examples] Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples, but rather brings about the following developments.

Example 1 A polymer array fiber having a commercially available expandable polystyrene bead as the foam resin portion (A), polyethylene terephthalate as the core component and a polystyrene copolymer as the sheath component as the composite fiber portion (B) (fiber length: 51 mm) was used. The ratio of both parts was A / B = 80/20. Next, the expandable polystyrene beads were blown with steam to be heated to produce primary expanded beads. The primary expanded beads and the polymer array fibers were mixed and filled by ejecting each from a separate ejector into a molding die partly opened. Then, steam was blown into the molding die to heat it again for secondary foaming, and at the same time, the foam resin and the composite fiber were bonded and integrated to produce a molded product. This foam block was one in which the composite fiber was uniformly dispersed in the foam resin and was well bonded and integrated.

This foam block (length 1820mm, width 920mm, thickness 920mm
Cube) was used to form a paved road model by stacking 5 layers in the vertical direction, 5 columns in the horizontal direction and 5 columns in the width direction to form a foundation, and placing concrete in the upper layer.

On this road model, we carried out repeated running tests by loading a jari on a truck and observed the displacement of the recesses in the wheels. A foam block without fiber reinforcement was used as a comparative example. As a result, it was observed that the road model using the foam block for civil engineering foundation of the present invention had a significantly smaller displacement than the comparative example.

Example 2 Polymer array fibers having a core component of nylon 66 and a sheath component of styrene / 2-ethylhexyl acrylate copolymer (number of cores in one filament: 36, single yarn fineness: 10 denier)
A woven fabric was made using the above, and the same die as in Example 1 was used to dispose on the inner wall surface of the forming die.

The space of the inner volume of the molding die was filled with expandable beads of polystyrene that had undergone primary expansion, and heated by steam to perform foam molding.

The foam block obtained is one in which the sheath component of the polymer array fiber is plasticized on the outer surface of the foam resin and the woven fabric consisting of the core component is covered, and the woven fabric and the foam resin are bonded together. The integration was extremely good and had a woven structure.

Using this foam block as a base material for paved roads, the same test as in Example 1 was conducted. As a result, it was observed that the displacement of the recesses in the rings was significantly smaller than that in the comparative example.

[Effects of the Invention] The foam block for civil engineering foundations of the present invention is one in which a foam resin made of a high-rigidity resin is reinforced by at least one of a composite fiber having good adhesion and high strength and the cloth. It has excellent dimensional stability against external stress and good mechanical performance such as good compressive strength and tensile strength.

The foam block for civil engineering foundation of the present invention is a bridge, an airfield,
By using it as a basic material for paved roads, railways, etc., it is possible to make a safe ground that is unlikely to cause subsidence or ground flow over a long period of time.

Claims (9)

[Claims] 1. The flexural modulus of a non-foamed resin alone is 150 kg / mm.
Reinforced by at least one of a composite fiber and a composite yarn, which is composed of a foam resin composed of a resin having high rigidity of ² or more, and the foam resin has an adhesive component and a fibrous component in the fiber and is sufficiently stretched in the axial direction of the fiber. A foam block for civil engineering foundations that is characterized by being 2. A foam block for civil engineering foundation whose surface and / or interior is reinforced by mixing at least one of a composite fiber and a composite yarn, wherein the composite one component is thermally deformed or melted by heat treatment. 2. The foam block for civil engineering foundation according to claim 1, wherein the foam block serves as an adhesive component, and other components are present as fibrous components to reinforce the foam resin. 3. A foam block for civil engineering foundation, wherein at least one of the surface and the inside is reinforced with a fabric composed of at least one of a composite fiber and a composite yarn, and the composite one component is thermally deformed by heat treatment. Alternatively, the foam block for a civil engineering foundation according to claim 1, wherein the foam block is melted to become an adhesive component, and other components are present as fibrous components to reinforce the foam resin. 4. A foam block for civil engineering foundation, wherein at least one of the surface and the inside is reinforced by mixing of at least one of a composite fiber and a composite yarn and a fabric constituted by at least one of the composite fiber and the composite yarn. hand,
The civil engineering according to claim 1, wherein the composite one component is thermally deformed or melted by heat treatment to be an adhesive component, and the other component is present as a fibrous component to reinforce the foam resin. Foam block for foundation. 5. The foam block for civil engineering foundation according to claim 2, 3, or 4, wherein the heat treatment includes a foaming treatment. 6. The foamed resin is a polymer containing a styrene monomer unit, and the foamed resin is a polymer containing a styrene monomer unit.
The foam block for civil engineering foundations according to claim 3 or 4. 7. The civil engineering work according to claim 1, 2, 3 or 4, wherein the adhesive component in the composite fiber is a polymer containing the same monomer units as the foam resin. Foam block for foundation. 8. The composite fiber and / or the composite yarn, wherein at least one of them is a core-sheath type fiber.
The foam block for civil engineering foundations according to item 2, 3, or 4. 9. The foam block for civil engineering foundation according to claim 8, wherein the core-sheath type composite fiber structure is a multi-core sheath type fiber.