JP2008050727A5 - - Google Patents

Description

Civil engineering materials and construction methods

The present invention relates to a civil engineering material and a construction method thereof , and more particularly to a civil engineering material used for revetment, slope protection and landscape decoration, and a construction method thereof .

  Conventionally, concrete is used for the purpose of revetment and slope protection. On the other hand, in recent years, a sheet using natural stone, stone or gravel generated at a construction site has been adopted as a more natural-friendly construction method.

  For example, Patent Literature 1 and Patent Literature 2 disclose a method of fixing a block stone material to a mat-like sheet by using a connector. However, this method requires a step of applying an adhesive for temporarily fixing the block stone to the sheet in advance, a step of making a hole in the block stone, and a step of bonding with a connector. Furthermore, although it is necessary to perform such a process with respect to the stone material generated at the construction site, there is a drawback that it is difficult to cope with it because it is the construction site.

In addition to the above, Patent Document 3 and Patent Document 4 disclose a method of adhering a lump to a mesh sheet via mortar or an adhesive. However, the method of bonding via mortar or adhesive not only leaves concerns about the alkaline components generated from the mortar and the environmental pollutants generated from the adhesive, but it is also created by bonding the lump in advance elsewhere It is necessary to transport the laid sheet to the construction site and lay it down, which is difficult to construct at the site.
JP 2003-321822 A JP 2005-139708 A JP 2005-344479 A Japanese Patent Laid-Open No. 11-303085

  In the conventional method as described above, there are a plurality of steps as described above, and workability is poor. In addition, it is difficult to work on site with a gradient.

The present invention has been made in view of such a current situation, and by making it possible to fix a lump such as stones and gravel generated on site to a sheet without moving to another site, workability is good. The purpose is to provide civil engineering materials and construction methods .

  As a result of intensive studies to solve such problems, the present inventors put a lump such as stone or gravel heated above the melting point of the thermoplastic resin on a sheet made of the thermoplastic resin. As a result, the inventors have found a method of heat-sealing on a sheet, and have reached the present invention.

  In addition, as a result of intensive studies to solve such problems, the present inventors have found that the second thermoplastic resin and a lump such as stone or gravel are formed on the sheet made of the first thermoplastic resin. The present inventors have found a construction method in which the second thermoplastic resin is charged in a state of being heated to the melting point or higher and heat-sealed on the sheet, and the present invention has been achieved.

  That is, the present invention has the following gist.

(1) A lump such as stone or gravel is bonded to a sheet composed of a synthetic fiber woven or knitted fabric formed of a thermoplastic resin by heat-sealing the thermoplastic resin. Civil engineering materials characterized by

(2) The synthetic fiber is a composite fiber having a core part and a sheath part in the fiber cross section, and a mass is adhered to the sheet by heat fusion of the sheath part (1) Civil engineering materials.

(3) The civil engineering material according to (1) or (2), wherein the thermoplastic resin is polylactic acid.

(4) A lump such as stone or gravel heated to a temperature equal to or higher than the melting point of the thermoplastic resin is put on a sheet composed of a synthetic fiber woven or knitted fabric formed of a thermoplastic resin. The construction method for civil engineering materials, wherein the lump is adhered to the sheet by heat-sealing the thermoplastic resin.

(5) The civil engineering according to (4) , wherein as the synthetic fiber , a composite fiber having a core portion and a sheath portion in a fiber cross section is used, and a lump is adhered to the sheet by heat fusion of the sheath portion. Material construction method.

(6) The construction method for civil engineering materials according to (4) or (5) , wherein polylactic acid is used as the thermoplastic resin.

  According to the present invention, it is possible to lay civil engineering materials in which a lump is fixed to a sheet under good workability and without moving lump such as stone or gravel generated on the site to another site. Can do.

  Hereinafter, the present invention will be described in detail.

The sheet formed of the thermoplastic resin used in the present invention is a woven or knitted fabric in which fibers are knitted and woven . Any material may be used as long as it melts and adheres to a lump such as stone or gravel heated to the melting point of the thermoplastic resin.

Since the sheet is a woven or knitted fabric in which fibers are knitted and woven, it can exhibit better adhesiveness than a film-like sheet having a large shrinkage. Further, since it is a sheet of woven or knitted fabric, it has better water permeability than that of a film-like sheet when exposed to rain or the like, so that it is easy for rainwater to escape and the possibility of pool water is reduced. The most preferred form is a knitted fabric, which may have better water permeability than a relatively dense fabric. In a woven fabric, if the fabric density is made too rough in order to improve water permeability, the yarns constituting the woven fabric may be shifted, and not only the appearance will be poor, but also the places where the clumps adhere will be random. Locations that are not firmly fixed tend to occur. A method of fixing with a weaving structure that does not deviate to some extent, such as a mimic structure, is useful, but when the mesh size is 3 cm or more, deviation also occurs. The structure of the knitted fabric is not particularly limited. However, in the case of a knot or knot, the strength of the entire knitted fabric is poor when one place is cut, and a raschel knitting structure is difficult because it is difficult to cut one place continuously. .

For a thermoplastic made of a resin sheet material, not particularly limited as long as it is a thermoplastic material. Considering cost and availability of sheet material, it is preferable to use a general-purpose thermoplastic resin. For example, acrylic resin, polyamide resin, aromatic / aliphatic polyester resin, polyurethane resin, polyolefin resin Examples thereof include resins, polycarbonate resins, polystyrene resins, ABS resins, fluorine resins, chlorine resins including vinyl chloride and vinylidene, and copolymers and mixtures thereof. In order to constitute a woven or knitted fabric, it is preferable to use melt-spun fibers of these resins. More preferably, it is possible to use a polyester-based resin or a polyamide-based resin that can obtain a relatively high strength when fiberized. The fineness of the synthetic fiber is not particularly limited, but fibers having a single yarn fineness of 4 dtex or more and a total fineness of 500 dtex or more are preferable because the mechanical properties are good.

As a fiber which comprises a sheet | seat, it is a composite fiber provided with the core part and the sheath part in the fiber cross section, for example, and the thing by which a lump is adhere | attached on a sheet | seat by heat sealing | fusion of the said sheath part can also be used. In this case, as long as the sheath is melted during heat-sealing and is used for adhesion of the lump, and the core does not melt and maintains the fiber form, reliable adhesiveness and sheet form It is possible to combine retention. For this purpose, the melting point of the thermoplastic resin constituting the sheath part is preferably 10 ° C. or lower than the melting point of the thermoplastic resin constituting the core part.

  In the case of a composite fiber having a core-sheath structure, specifically, the thermoplastic resin of the core part and the sheath part is a polyester resin for both the core part and the sheath part, or the polyamide resin for both the core part and the sheath part. That is, it is advantageous that the resin is of the same series at the time of regeneration or disposal. Specifically, if the resin is a general-purpose resin such as the above-described polyester resin or polyamide resin, a combination in which the core is polyethylene terephthalate and the sheath is a copolymer thereof, or the core is nylon 66 and the sheath is nylon 6 The combination etc. which are can be mentioned. It is also preferred that both the core and the sheath are biodegradable resins.

As a biodegradable resin, that is, a thermoplastic material having biodegradability, an aliphatic polyester resin is preferable in view of cost and availability of a sheet material, and polylactic acid, polybutylene succinate resin, and copolymers thereof. And mixtures can be used. Among these, polylactic acid is particularly preferable because it can provide a relatively high strength when fiberized.

The above thermoplastic resin may be added various additives according to the purpose. Specifically, antioxidants such as phenols, organic phosphites, and organic phosphorus and thioethers such as eggplants; hindered amines, benzophenones, benzotriazoles, benzoates, and other antifungal agents; nonionics, cationics Antistatic agents such as anion type; dispersants such as bisamide type, wax type and organic metal salt type; lubricants such as amide type, wax type, organic metal salt type and ester type; bromine-containing organic type, phosphoric acid type, Examples thereof include flame retardants such as antimony trioxide, magnesium hydroxide, ammonium phosphate, and red phosphorus; and colorants such as carbon black and pigments. These additives can be appropriately combined and blended in any step of producing the material composition. As a method of blending the additive, a conventional kneading apparatus such as a single or twin screw extruder, a Banbury mixer, a kneader, a mixing roll and the like are mixed in a predetermined ratio, and this is melt-kneaded and adjusted. Alternatively, a so-called master batch having a high concentration may be prepared and used after being diluted.

  Examples of the lump such as stone and gravel used in the present invention include cobblestone, cracked stone, crushed stone and concrete lump generated in the field, but are not particularly limited thereto.

  There is no particular limitation on the method of heating the lump such as stone or gravel, either directly using a fire source such as a burner, or indirectly by heating the ambient temperature like a dryer. And heating method. As an on-site response, an asphalt mixing device used when constructing an asphalt road can also be used.

  Next, examples of the present invention will be described in detail.

  A test was conducted in which civil engineering materials using sheets of the following examples were laid on an artificially made 5-minute gradient slope. At this time, approximately 15 cm of cracked stone was used as the lump. As a heating device, an asphalt recycle machine (manufactured by Kaimori Machinery Co., Ltd., `` Astaro '') was used, and the granite and thermoplastic resin as a block were heated to different temperatures for each example as described below. . When laying the civil engineering material, the sheet of each example was laid in advance with a size of 2 m × 2 m on the gradient slope, and fixed with a metal pile at a pitch of 50 cm. Then, about 100 kg of the walnut stone that had been heated from above was added, and the state of adhesion was confirmed after cooling.

Example 1
A master chip was manufactured by mixing nylon 6 chip (melting point: 215 ° C.) with 10% by mass of titanium black and 1% by mass of copper iodide. 4 parts by mass of the master chip and 96 parts by mass of the same nylon 6 chip used for the master chip are mixed, melt-spun using an extruder-type spinning machine, and stretched to have a strength of 8.2 cN / dtex, Original nylon fibers of 1590T210 and 3120T420 having an elongation of 25% and a dry heat shrinkage of 10% were obtained.

  The obtained 3120T420 original nylon fiber was used as a chain knitting yarn, 1590T210 original nylon fiber was used as an insertion yarn, and knitting was performed using a 9G Russell knitting machine. This warp knitted fabric was heat-treated at 180 ° C. for 1 minute to obtain a net having a mesh side of 25 mm as the sheet of Example 1.

(Example 2)
54 yarns 1670T192 original nylon fibers produced by the same method as in Example 1 are twisted together to form a braided net having a mesh size of 25 mm × 25 mm, and the sheet of Example 2 Got the net as.

(Example 3)
A yarn 1670T192 original nylon fiber produced in the same manner as in Example 1 was twisted at 80 T / m and woven in a plain structure with a fabric density of 24 / 2.54 cm × 24 / 2.54 cm. As a sheet, a woven fabric was obtained.

Example 4
The original nylon fiber of the yarn 1670T192 produced by the same method as in Example 1 was twisted at 80 T / m, and using this twisted yarn, a fabric density of 33 / 2.54 cm × 33 / 2.54 cm, 6 1 The woven fabric as a sheet of Example 4 was obtained.

(Summary of Examples 1-4)
About the sheet | seat of Examples 1-4 , it tested, after heating a block to 220 degreeC. As a result, it was confirmed that in each of the sheets of Examples 1 to 4 , the split stones were well fixed to the sheets.

In Example 2, there was a portion where a part of the net was completely dissolved, and the mesh was not completely fixed, and a slight lifting phenomenon was confirmed on the sheet. In Example 3, there was no particular problem during the test, but some accumulated water was observed during the rain. In Example 4, a slight misalignment occurred when laying on the slope . On the other hand, the sheet of the raschel knitted fabric of Example 1 was the best.

( Example 5 )
Polyethylene terephthalate (melting point 260 ° C.) containing 1% carbon black was used as the core of the core-sheath composite fiber. As a sheath part of the fiber, a polyethylene terephthalate oligomer having a molar ratio of a terephthalic acid component to an ethylene glycol component of 1: 1.13, 15 mol% of ε-caprolactone based on the total acid component, and 1,4-butane A copolymerized polyester (melting point: 160 ° C.) polymerized by adding diol at a ratio of 50 mol% with respect to all diol components was used. A multifilament made of a core-sheath composite fiber in which each of the polyester-based polymers described above was arranged in a core part and a sheath part and the mass ratio of the core / sheath was 50/50 was obtained using a conventional composite spinning machine. . The resulting 3330T360 original polyester core / sheath conjugate fiber was used as a chain knitting yarn, and 1670T120 original polyester core / sheath conjugate fiber was used as an insertion yarn, and knitted using a 9G Russell knitting machine. This warp knitted fabric was heat-treated at 120 ° C. for 1 minute to obtain a net as a sheet of Example 5 having a mesh side of 25 mm.

( Example 6 )
54 yarns 1670T120 of the original polyester core-sheath composite fiber produced by the same production method as in Example 5 were twisted together to form a sheet of Example 6 with a mesh size of 25 mm × 25 mm. Got a net.

( Example 7 )
The original polyester core-sheath composite fiber of the yarn 1670T120 produced by the same production method as in Example 6 was twisted at 80 T / m, and using this twisted yarn, the fabric density was 24 / 2.54 cm × 24 / 2.54 cm. A woven fabric was obtained as a sheet of Example 7 by weaving with a plain structure.

( Example 8 )
An original polyester composite core-sheath fiber of yarn 1670T120 produced by the same production method as in Example 6 was twisted at 80 T / m, and using this twisted yarn, the fabric density was 33 / 2.54 cm × 33 / 2.54 cm. Weaving was carried out with a complete imitation structure of 6 pieces to obtain a woven fabric as a sheet of Example 8 .

( Example 9 )
Nylon 66 containing 1% carbon black (melting point: 260 ° C.) was used as the core of the core-sheath composite fiber. Nylon 6 (melting point: 215 ° C.) was used as the sheath of the fiber. Then, a multifilament composed of core-sheath composite fibers having a core / sheath mass ratio of 50/50 was obtained using a conventional composite spinning machine by arranging each nylon polymer in the core and sheath. The obtained 3120T360 original nylon core-sheath conjugate fiber was used as a chain knitting yarn, and 1590T90 original nylon core-sheath conjugate fiber was used as an insertion yarn, and knitted using a 9G Russell knitting machine. This warp knitted fabric was heat-treated at 120 ° C. for 1 minute to obtain a net having a mesh side of 25 mm as the sheet of Example 9 .

(Summary of Examples 5-9 )
For the sheets of Examples 5-8 , the mass was heated at a set temperature of 170 ° C. For the sheet of Example 9 , the lump was heated at a set temperature of 220 ° C. As a result, it was confirmed that the walnut stone as a lump was fixed to the sheets well in the sheets of Examples 6 to 9 .

In Example 6 , there was a portion where a part of the net was completely dissolved, and the mesh was not completely fixed, and a slight lifting phenomenon was confirmed on the sheet. In Example 7 , no particular problem occurred during the test, but some accumulated water was observed during rainfall. In Example 8 , a slight misalignment occurred when laying on the slope. On the other hand, the sheet of the raschel knitted fabric composed of fibers made of a thermoplastic material in Examples 5 and 9 was the best.

( Example 10 )
A polylactic acid chip (manufactured by Nature Works, product number: 6400, melting point: 180 ° C.) was mixed with 10% by mass of titanium black and 1% by mass of copper iodide to produce a master chip. 4 parts by mass of this master chip and 96 parts by mass of the same polylactic acid chip used for the master chip are mixed, melt-spun using an extruder-type spinning machine, and stretched to have a strength of 5.1 cN / dtex, Original polylactic acid fibers of 1590T210 and 3120T / 420 having an elongation of 30% and a dry heat shrinkage of 15% were obtained. The obtained 3120T / 420 original polylactic acid fiber was used as a chain knitting yarn and 1590T210 original polylactic acid fiber was used as an insertion yarn, and knitting was performed using a 9G Russell knitting machine. This warp knitted fabric was heat-treated at 120 ° C. for 1 minute to obtain a net having a mesh side of 23 mm as the sheet of Example 10 .

( Example 11 )
54 original polylactic acid fibers of the yarn 1670T192 produced by the same manufacturing method as in Example 10 were twisted together to form a cocoon net with a mesh size of 25 mm × 25 mm as the sheet of Example 12. Knitted.

( Example 12 )
The original polylactic acid fiber of the yarn 1670T192 produced by the same production method as in Example 10 was twisted at 80 T / m, and woven in a plain structure with a fabric density of 24 / 2.54 cm × 24 / 2.54 cm, A woven fabric as a sheet of Example 12 was obtained.

( Example 13 )
An original polylactic acid fiber of yarn 830T70 produced by the same production method as in Example 10 was twisted at 80 T / m, and using this twisted yarn, a fabric density of 33 / 2.54 cm × 33 / 2.54 cm was used. Weaving was performed with a complete imitation structure to obtain a woven fabric as a sheet of Example 13 .

(Example 14)
As a polylactic acid polymer to be arranged in the core of the core-sheath composite fiber, a copolymerized polylactic acid obtained by copolymerization of L-form of lactic acid at a ratio of 99 mol% and D-form of 1 mol% (manufactured by Cargill Dow, product number: 6200, melting point: 170 ° C.) containing 1% by mass of carbon black was prepared. On the other hand, as a polylactic acid polymer to be arranged in the sheath, a copolymerized polylactic acid (92 parts by weight of L-lactic acid and 8 mole% of D-form copolymer) (manufactured by Cargill Dow, product number: 6300, melting point) 130 ° C.). Using these polylactic acid-based polymers, a multifilament of core-sheath composite fiber having a core / sheath mass ratio of 50/50 (strength: 4.0 cN / dtex, elongation: 30) on a melt composite spinning machine. %, Dry heat shrinkage ratio: 14%). The obtained 3120T420 original polylactic acid fiber was used as a chain knitting yarn, 1590T210 original polylactic acid fiber was used as an insertion yarn, and knitted using a 9G Russell knitting machine. This warp knitted fabric was heat-treated at 100 ° C. for 1 minute to obtain a net having a mesh side of 23 mm as a sheet of Example 14 .

(Summary of Examples 10-14 )
About the sheet | seat of Examples 10-14 , the lump was heated to 185 degreeC in Examples 10-13 , and also tested in Example 14 , after heating to 145 degreeC. As a result, it was confirmed that in each of the sheets of Examples 10 to 14 , the cracked stones were well fixed to the sheets.

In the sheet of Example 11 , a portion where a part of the net was melted was generated, and the mesh was not completely fixed at that portion, and a slight lifting phenomenon was confirmed on the sheet. In Example 12 , there was no particular problem during the test, but some accumulated water was observed during the rain. In Example 13 , a slight misalignment occurred during slope laying . On the other hand, the sheet of the raschel knitted fabric composed of fibers made of the thermoplastic material having biodegradability of Examples 10 and 14 was the best.

In addition, since the sheets of Examples 10 to 14 have biodegradability, not only can the sheet itself be decomposed by being left for a long period of time, but a landscape closer to nature can be created, Environmentally friendly construction was possible.

( Example 15 )
A net produced by the same production method as in Example 5 was used as the sheet of Example 15 . In this net, as in Example 5 , the melting point of polyethylene terephthalate in the core part was 260 ° C., and the melting point of the copolyester in the sheath part was 160 ° C. As input materials, cracked stone and copolymer polyester (melting point: 160 ° C.) chips were used. The copolymerized polyester chip contains PET oligomer having a molar ratio of terephthalic acid component to ethylene glycol component of 1: 1.13, ε-caprolactone at 15 mol% with respect to the total acid component, and 1,4-butanediol. It was added and polymerized at a ratio of 50 mol% with respect to all diol components. And the copolymer polyester chip | tip was mixed with the ratio of 1 mass% with respect to walnut stone, and what heated at 190 degreeC * 2 minute was used.

In the sheet of Example 15, it was confirmed that the cracked stone is fixed to the sheet satisfactorily .

Claims (6)

A lump such as stone or gravel is bonded to a sheet composed of a synthetic fiber woven or knitted fabric formed of a thermoplastic resin by heat fusion of the thermoplastic resin. Civil engineering materials to be used. 2. The civil engineering structure according to claim 1, wherein the synthetic fiber is a composite fiber having a core portion and a sheath portion in a fiber cross section, and a mass is bonded to the sheet by heat fusion of the sheath portion. Materials.   The civil engineering material according to claim 1 or 2, wherein the thermoplastic resin is polylactic acid. A lump such as stone or gravel heated to a temperature equal to or higher than the melting point of this thermoplastic resin is put on a sheet composed of a synthetic fiber woven or knitted fabric made of a thermoplastic resin. A construction method for a civil engineering material, characterized in that an object is adhered to the sheet by thermal fusion of the thermoplastic resin. 5. The civil engineering material according to claim 4, wherein a composite fiber having a core portion and a sheath portion in a fiber cross section is used as a synthetic fiber , and a lump is adhered to the sheet by heat fusion of the sheath portion. Construction method.   The construction method for civil engineering materials according to claim 4 or 5, wherein polylactic acid is used as the thermoplastic resin.