JP2010043447A - Natural stone connecting member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a natural stone connection member firmly adhered to a natural stone, preventing the strength from being lowered due to rusting even when a plurality of natural stones connected to each other are laid down in water, and maintaining the firm connection to the natural stone over a long period. <P>SOLUTION: This member is used to connect a plurality of natural stones to each other. The member is formed of a fiber assembly containing fibers which has a sheath-core structure in which a sheath part lower in melting point than a core part is formed around the core part. The sheath part of the fiber assembly is heat-sealed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a natural stone connecting member, for example, a root construction to prevent scouring of a riverbed, a bank protection to protect the riverbank, a wavebreak to protect the coast, a sabo dam to prevent a large amount of sediment from flowing out during heavy rain, etc. The present invention relates to a natural stone connecting member for connecting a plurality of natural stones used as civil engineering structures.

  In order to protect rivers and coasts from high waves caused by typhoons, heavy rains, heavy rains, etc., rivers and coasts, various rooting and revetment methods are widely known. ing. However, when laying blocks or stones using the Negishi method or the revetment method, only a small amount on the river or coast does not have a stable weight / laying area. There is a risk of being swept away by intense water flow and water pressure. For this reason, when laying blocks and stones near rivers and coasts, many blocks and stones are often laid in a lump so that they have a somewhat stable weight and area so that they will not be washed away.

  A large number of blocks and stones laid in a lump aggregate are stably laid without being swept away even in the case of high waves due to river flooding or flooding or sea level rise on rivers and coasts. It has the effect of sufficiently protecting rivers and coasts, and also has a certain laying area, so that it can be laid over a wide area at a time, which leads to simplification of the laying work process and becomes efficient.

  In addition, when laying in a lump assembly, concrete blocks are used because the weight and shape can be freely designed and adjusted according to the laying location and purpose of use such as revetment, sand protection, and wave protection. Is often used. In particular, it is often found that concrete revetment structures such as loading blocks and tension blocks in rivers and wave-dissipating blocks on coasts are laid in various places. One method of laying the above-mentioned concrete blocks as a mass of aggregates on rivers and coasts is a connection method in which the blocks are connected to each other by a connecting member attached to the blocks to form a civil engineering structure. At this time, a metal product is often used as a connecting member that connects a plurality of concrete blocks used in civil engineering structures, and a plurality of blocks are connected by a metal product by various methods (for example, (See Patent Document 1).

  However, since the plurality of blocks connected by the connecting member are mainly laid in water, rust occurs when the connecting member is a metal product. Corrosion proceeds from the metal surface to the inside of the metal material in which rust has occurred, and thus the metal has no inherent strength. As a result, the strength as a member for connecting a plurality of blocks decreases, and the effectiveness as a connecting member cannot be fully exhibited.

  In recent years, it has become very important to suppress the generation of carbon dioxide, which is a greenhouse gas that affects global warming. Concrete, which is used as a civil engineering structure and is a raw material for blocks whose weight and shape can be freely designed and adjusted, can be obtained by cementing rock material with cement. However, carbon dioxide is released from the main raw material limestone in the process of producing quick lime as a cement component. That is, since concrete, which is a raw material for blocks that have been widely used as civil engineering structures, emits carbon dioxide when manufactured, the use of concrete blocks becomes a cause of global warming.

Therefore, there is a proposal that can reduce carbon dioxide emissions generated during cement generation and prevent global warming by using natural stones instead of concrete blocks in civil engineering structures. (For example, refer to Patent Document 2). However, even when natural stones are used in civil engineering structures, metal products are still used as connecting members that connect natural stones. However, the strength of the connecting member is inevitably lowered due to rust.
JP 2001-295248 A JP-A-10-331133

  The problem of the present invention is that the natural stone and the connecting member are firmly bonded, and even when a plurality of connected natural stones are laid in water, the strength of the connecting member due to rust does not decrease, and the natural stone is strong. An object of the present invention is to provide a natural stone connecting member that enables long-term connection.

  As a result of intensive studies to solve such problems, the present inventors have used a fiber assembly including fibers having a core-sheath structure as a member for connecting natural stones to each other, on the outer periphery of the fiber assembly. Since the adhesive does not penetrate into the fiber assembly due to the heat-sealing layer formed, the natural stone and the fiber assembly are firmly bonded, and even when multiple connected natural stones are laid in water It has been found that it is possible to provide a connecting member that is capable of providing a strong connection with natural stone for a long period of time.

That is, the present invention is (1) a fiber assembly including a fiber having a core-sheath structure in which a plurality of natural stones are connected to each other, and a sheath having a melting point lower than that of the core is provided around the core. A natural stone connecting member, wherein the sheath part of the fiber assembly is heat-sealed,
(2) The natural stone connecting member according to (1), wherein both the core and the sheath of the fiber having a core / sheath structure are polyester polymers,
(3) A concave portion is formed in each of the natural stones connected to each other, and the natural stone connecting member according to any one of (1) or (2) is partially inserted into the concave portion of each natural stone. Natural stone connection structure characterized by being fixed by an adhesive in the recess,
Is a summary.

  According to the present invention, a fiber having a core-sheath structure is included as a connecting member between natural stones constituting a civil engineering structure that protects against floods during heavy rains / intensifications and high waves during bad weather in rivers, coasts, riverbanks, etc. By using the fiber assembly, a heat-sealing layer is provided on the outer periphery of the fiber assembly, so that the adhesive does not penetrate into the fiber assembly and the loss of the adhesive can be reduced, so that natural stone and the fiber assembly are strong. It is possible to provide a connecting member that does not decrease the strength as a connecting member even when it is bonded to water and is laid in water, and that enables a strong connection with natural stone for a long period of time.

Hereinafter, the present invention will be described in detail. However, the present invention is not limited to this content.
The natural stone connecting member of the present invention is a core-sheath structure in which a member for connecting a plurality of natural stones, which are constituents of a civil engineering structure, is provided with a sheath having a lower melting point than the core around the core. It is comprised by the fiber assembly containing the fiber which has this, The heat-sealing was given to the said sheath part of this fiber assembly, It is characterized by the above-mentioned.

  In the present invention, natural stone is used as a structure of a civil engineering structure instead of a conventionally used concrete block. The fiber assembly inserted in the concave portion of the natural stone is fixed to the natural stone by an adhesive in the concave portion of the natural stone. However, in the past, since a concrete block was used as a component of a civil engineering structure, when an adhesive was poured into the concave portion provided in the concrete block, countless fine dots scattered on the concave surface of the concrete block. Since the adhesive penetrates into the gap, the amount of the adhesive that is originally required is reduced. As a result, when a concrete block is used as a component of the civil engineering structure to be connected, the adhesion between the fiber assembly and the concrete block is deteriorated. On the other hand, when the natural stone of the present invention is used as a structure of a civil engineering structure, there is no decrease in the amount of adhesive because there are innumerable fine voids on the surface of the natural stone, and the connecting member can be used with the originally required amount of adhesive. Adhesive with natural stones. Furthermore, since carbon dioxide generated in the block raw material concrete generation process is not generated, it becomes possible to reduce the discharge of carbon dioxide into the atmosphere, leading to prevention of global warming.

  Moreover, in this invention, a fiber assembly is used instead of the metal product conventionally used as a connection member which connects natural stones. As a result, even when natural stone is laid in water, the connecting member does not rust, so the strength of the connecting member due to rust does not decrease, and it is possible to provide a natural stone connecting member that can be used for a long time. Become.

  The fiber aggregate in the present invention is fixed to the natural stone by the adhesive in the concave portion after being inserted into the concave portion of the natural stone. The fiber assembly to be inserted into the recess needs to include a fiber having a core-sheath structure in which a sheath having a lower melting point than that of the core is provided around the core. Fibers having a core-sheath structure are heat-treated at a temperature equal to or higher than the melting point of the fibers of the sheath part and lower than the melting point of the fibers of the core part, so that the sheath part having a lower melting point than the core part melts. Adhesion is caused to form a heat fusion layer. At that time, each fiber in the fiber assembly is fixed by heat fusion, and the outer periphery of the fiber assembly is covered with the heat fusion layer, so that the fiber assembly is not covered with the heat fusion layer. Since the adhesive does not penetrate into the fiber assembly, the natural stone and the fiber assembly are securely bonded. That is, since adjacent fibers in the fiber assembly are fixed by heat-sealing, a fiber assembly that does not lose fiber even when individual fibers are pulled can be obtained, and the adhesive to the inside of the fiber assembly can be obtained. A fiber assembly having no penetration and excellent adhesion to natural stone is obtained.

  The amount of the core-sheath structure fiber contained in the fiber assembly is preferably 20% by mass or more, and more preferably 40% by mass or more. That is, when the content of the core-sheath structure fiber is 20% by mass or more, the outer periphery of the fiber assembly is covered with the heat-sealing layer, so that the adhesive does not penetrate into the fiber assembly and has an adhesive force with natural stone. However, when the amount is 20% by mass or less, it becomes difficult to form a heat-sealing layer on the outer periphery of the fiber assembly. Therefore, most of the adhesive necessary for bonding the fiber assembly to natural stone is a bundle of fiber assemblies. It is not preferable because it penetrates between the fibers constituting the material and the amount of adhesive which is originally necessary for adhesion is insufficient.

  Here, when the fiber assembly does not include the core-sheath structure fiber, in order to obtain a required adhesion effect so that the adhesive force between the fiber assembly inserted into the natural stone recess and the natural stone does not decrease, the fiber assembly It is necessary to perform post-processing after the outer periphery of the resin is coated and hardened with a resin or the like that is difficult for the adhesive to penetrate. By covering and solidifying the outer periphery of the fiber assembly with a resin or the like, the adhesive does not penetrate into the fiber assembly, so that the fiber assembly is maintained while maintaining a sufficient amount of adhesive for bonding with natural stone. This is because an adhesive effect with natural stone can be obtained.

  On the other hand, since the fiber assembly of the present invention includes the core-sheath structure fiber, a heat-seal layer is formed on the outer periphery of the fiber assembly due to the heat-seal effect, and the adhesive does not permeate. There is an advantage that it is not necessary to provide. Therefore, the cost necessary for providing another resin layer on the outer periphery of the fiber assembly can be suppressed, which is effective.

  The fiber assembly including the fiber having the core-sheath structure may be composed of a core-sheath structure fiber and another fiber, or may be composed of a fiber containing 100% of the core-sheath structure fiber. That is, the core-sheath structure fiber and other fibers may be used as a fiber assembly, or the core-sheath structure fiber alone may be used as a fiber assembly. At this time, other fibers contained in the fiber assembly are optional, but it is necessary that the fiber assembly does not melt at the melting point of the sheath portion of the fiber having the core-sheath structure at the time of heat treatment of the fiber assembly. This is because, when other fibers are melted during the heat treatment of the fiber assembly, the fiber form is not retained.

  It is preferable that the fiber assembly in the present invention has a core-sheath structure including a core part and a sheath part. For example, as a fiber assembly having a core-sheath structure, a core portion of a fiber assembly is formed by twisting a plurality of yarns or strands, and another plurality of yarns or strands are arranged around the core portion. By configuring the sheath of the fiber assembly, it is possible to form a rope or braid. At that time, the core portion of the fiber assembly can be composed of only the fibers of the core-sheath structure, and can be composed of fibers other than the core-sheath structure fiber, or It can also be composed of a mixture with other fibers. Moreover, the sheath part of a fiber assembly needs to be comprised only with a core sheath structure fiber, or to be comprised with the mixture of a core sheath structure fiber and another fiber. That is, it is necessary to include at least the core-sheath structure fiber. If the sheath portion of the fiber assembly does not contain core-sheath structure fibers, the heat fusion layer due to the heat fusion effect is not formed on the outer periphery of the fiber assembly, the adhesive penetrates into the fiber assembly, and natural stones and This is because the adhesive strength of the is deteriorated.

  The fiber constituting the fiber assembly in the present invention and the core-sheath structure fiber comprising the core part and the sheath part are any fiber using a polymer such as polyamide, aliphatic polyester, aromatic polyester, vinylon, polypropylene, aramid, etc. Alternatively, the fiber cross section may be a round cross section, a flat or irregular cross section.

  As for the fiber which has a core sheath structure in this invention, it is more preferable that both a core part and a sheath part are polyester polymers. That is, it is preferable that the core part of the core-sheath structure fiber is made of a polyester polymer and the sheath part is made of a polyester copolymer having a melting point lower than that of the polyester polymer of the core part. As such a fiber, for example, “Melset” manufactured by Unitika Fiber Co., Ltd. having a core-sheath structure in which high-viscosity polyester is arranged in the core and copolymer polyester is arranged in the sheath is suitable. .

  Moreover, as a fiber assembly in this invention, when a core-sheath structure fiber and another fiber are mixed, it is desirable that the core-sheath structure fiber and the other fiber are composed of an equivalent polymer. When the core-sheath structure fiber and other fibers are composed of different polymers, the compatibility between the core-sheath structure fiber and the other fibers is low, and the core-sheath structure fiber becomes a fusion component during heat fusion. It becomes difficult for the sheath portion of the fiber to adhere to other fibers, or the fibers may come off when pulled.

  The core-sheath structure fiber and other fibers that can be used in the fiber assembly in the present invention may be functional fibers to which a colorant, an antibacterial agent, a weathering agent, or the like is added, or those using pre-dyed yarn. Absent.

  The connecting structure using the natural stone connecting member of the present invention is a structure in which a fiber assembly in which a heat-sealing layer is formed on the outer periphery serving as a connecting member is partially inserted into a concave portion provided in the natural stone and fixed with an adhesive. However, it is sufficient that the natural stones are connected to each other by using the fixed fiber aggregate, and the shape is exemplified by connecting the natural stones by a single cord-like fiber aggregate. can do. Alternatively, the other end of the fiber assembly opposite to the one end connected to the natural stone is in the form of a hook or a loop, and it is only necessary to be able to link the fiber assemblies using the other end, There is no particular limitation.

Specific examples of such a connection structure are shown in FIGS.
As shown in FIG. 1, one end of a connecting member on which the heat-bonded layer 5 is formed by heat-treating the cord-like fiber assembly 2 is inserted into the concave portion 3 of one natural stone 1, and the other end of the connecting member is inserted. The structure which inserts in the recessed part 3 of the other natural stone 1, and fixes and connects each inserted part with the adhesive agent 4 is mentioned.

  Further, as shown in FIG. 2, a connecting member having a hook 6 formed at the tip is prepared and bonded to the natural stone 1 with the adhesive 4. It is assumed that the hook 6 is obtained by heat-sealing the sheath portion of the core-sheath structure fiber or having been hardened with a resin so as to have a required strength at the time of connection. The natural stones having the hooked connecting portions obtained in this manner are hooked together as shown in FIG. 3 so that the natural stones are connected.

Moreover, it is good also as a state which connected the some natural stone using the connection members which made the connection part the structure of the loop shape 7 like FIG.
Moreover, the fiber assembly used as a connection member needs to have the strength exceeding the total weight of the natural stone after connection, and the safety factor of the fiber assembly with respect to the total weight of the natural stone after connection ( That is, it is preferable that the safety factor = the strength of the fiber assembly / the total weight of the natural stone after connection) is 1.1 to 1.5. If the safety factor is less than 1.1, the strength of the connecting member is lost to the total weight of the natural stone after the connection, which is dangerous because the fiber assembly is cut in the lifting work at the time of laying. On the other hand, if the safety factor is 1.5 or more, the connecting member has an unnecessarily strong force, leading to an extra cost for the connecting member.

  The total weight of the plurality of natural stones connected by the connecting member is generally 2t to 5t. Therefore, it is assumed that the strength of the fiber assembly serving as the connecting member needs to be able to withstand this total weight, and it is necessary to determine the strength of the fiber assembly based on the balance with the safety factor described above. There is. Since the fiber assembly of the present invention includes core-sheath structure fibers, a heat-sealing layer is formed on the outer periphery of the fiber assembly due to the heat-seal effect, and each fiber is heat-sealed, so that the connecting member As a result, a fiber assembly having sufficient tensile strength to be used as a fiber is obtained.

  In addition, rivers, coasts, harbors, lake shores, etc. are under severe conditions as environments where civil engineering structures are used. Therefore, there are various degradation factors, and in particular, degradation due to the climate is the greatest concern. That is, civil engineering structures laid on rivers, coasts, harbors, lake shores, etc. are generally required to have a durability of about 30 years after laying. However, since the connecting member of the present invention is not a metal product, it is laid in water. In this case, since rust does not occur, it has a strength suitable as a connecting member and can maintain the strength as a connecting member for a long period of time.

  Furthermore, the fiber assembly constituting the connecting member of the present invention includes fibers having a core-sheath structure as described above, and the outer periphery of the fiber assembly is covered with a heat-sealing layer. The weather resistance is improved because it prevents the fiber from entering the fiber. On the other hand, when the connecting member is composed of fibers that do not contain core-sheath structure fibers, the surface of the fiber assembly is not covered at all, so sunlight and ultraviolet rays enter the inside of the fiber assembly. Deteriorated easily by light and ultraviolet rays.

  As the durability of the natural stone connecting member of the present invention, it is preferable to have the strength of the safety factor 1.1 to 1.5 described above even after 30 years of laying. Long-term strength retention needs to be determined by the strength of the fiber assembly in consideration of weather resistance degradation, and the strength degradation of the fiber assembly after weather resistance is preferably less than 40%, particularly preferably less than 20%. When the strength deterioration of the fiber assembly after weathering is 40% or more, the amount of fibers that are required to form the fiber assembly to increase the safety factor 1.1 to 1.5 is increased, thereby reducing the cost. It becomes high and is not preferable.

  The total fineness and diameter of the fiber assembly are particularly limited as long as the total strength calculated from the strength of the single fibers constituting the fiber assembly is designed to be within the range of the safety factor described above. It is not a thing and can change suitably with the total weight of the natural stone after connection.

  The fineness of the single fiber constituting the fiber assembly is not particularly limited, but is preferably 280 dtex to 3000 dtex. If the fineness of the single fiber is 280 dtex or less, the strength of the single fiber is weak, so that a large number of fibers are used when forming the fiber assembly, which is very laborious in work. Further, when the fineness of the single fiber is 3000 dtex or more, it becomes difficult to produce the raw yarn.

  The adhesive used for fixing the natural stone and the connecting member is not particularly limited. Examples of the adhesive include inorganic adhesives, organic adhesives, natural adhesives, and synthetic adhesives. However, in consideration of firmly fixing the connecting member to natural stone, a synthetic adhesive is preferable. Specifically, solution-types typified by α-olefin-based adhesives, urethane resin solvent-based adhesives and ether-based cellulose, acrylic resin-based adhesives, epoxy resin-based adhesives, silicone-based adhesives, etc. Examples thereof include a reaction system represented by an aqueous dispersion system represented by an acrylic resin emulsion adhesive, a urethane resin emulsion adhesive, and an epoxy resin emulsion adhesive. A reaction system is preferable for obtaining a strong adhesive effect on a stone or the like, and an acrylic resin adhesive is particularly preferable.

Next, the present invention will be specifically described with reference to Examples and Comparative Examples. In addition, the measurement and evaluation of each value in an Example and a comparative example were performed as follows. Moreover, the connection member for connecting the natural stones whose total mass after a connection is 3t was used for the sample of an Example and a comparative example.
(1) Tensile strength Using an autograph AG-I type manufactured by Shimadzu Corporation, the tensile strength of a test piece having a sample length of 25 cm was measured at a tensile speed of 30 cm / min. did.
(2) Weather resistance (post-weather strength and appearance observation)
An acceleration test was conducted using a sunshine weather meter manufactured by Nishiyama Seisakusho, and the tensile strength and appearance after 7500 hours of irradiation were observed. Appearance observation was performed visually to evaluate the presence or absence of changes before and after the test.
(3) Adhesion situation After putting adhesive (acrylic resin adhesive) into the concave part of natural stone, observe the adhesive state between the natural stone and the sample inserted into the concave part after inserting the sample into the concave part and leaving it for 1 hour. And evaluated according to the following criteria.
○: Adhered completely.
Δ: Part of the sample is adhered.
X: Not bonded.
Example 1

Six 1100 dtex core-sheath fibers having a polyester copolymer (melting point 260 ° C.) in the core and a polyester copolymer (melting point 160 ° C.) having a lower melting point than the core in the sheath (Z A core yarn was formed by twisting with -250 T / m, lower twist) × 3 pieces (S-120 T / m, upper twist). Next, the obtained five core yarns were twisted with a twist number of S-60 T / M to obtain a rope core.
On the other hand, a sheath yarn was formed by twisting under the same conditions as the core yarn.
The rope core portion was covered with S-60 T / M by eleven sheath yarns obtained to cover the periphery of the rope core portion. One strand was obtained by these rope core part and rope sheath part. Three strands of this strand were twisted at a twist number of Z-25 T / M to obtain a rope with a total rope fineness of 950400 dtex and a rope diameter of 14 mm.
The obtained rope is heat-treated at 200 ° C. for 10 minutes, which is a temperature range above the melting point of the polyester copolymer constituting the sheath portion of the core-sheath fiber and less than the melting point of the polyester copolymer constituting the core portion. As a result, the sheath yarn which is the sheath portion of the strand constituting the rope is heat-sealed to form a fiber assembly in which a heat-sealing layer is formed at least on the outer periphery of the rope. A connecting member was obtained.
(Example 2)

For the rope core, only polyethylene terephthalate multifilament (melting point 260 ° C., hereinafter referred to as PET) was used instead of the core-sheath structure fiber used in Example 1. Otherwise, a rope core was obtained in the same manner as in Example 1. The obtained rope core part was comprised only by PET, and did not have a core sheath structure fiber.
A sheath yarn was formed under the same conditions as in Example 1.
Using 11 obtained sheath yarns, the periphery of the rope core portion made of PET alone was covered with S-60T / M to constitute a rope sheath portion. One strand was obtained by these rope core part and rope sheath part. Three strands of this strand were twisted at a twist number of Z-25 T / M to obtain a rope having a total rope fineness of 950400 dtex and a rope diameter of 14 mm.
Thereafter, the natural stone connecting member of Example 2 was obtained in the same manner as Example 1.
In addition, the ratio of the core-sheath structure fiber which comprises the sheath yarn which covered the circumference | surroundings of PET used for the rope core part of the said sample and a rope core part is core-sheath structure fiber: PET = 69: 31 (mass% ratio). there were.
(Example 3)

Using only PET instead of the core-sheath structure fiber used in Example 1, PET of 1100 dtex is 6 (Z-250 T / m, lower twist) × 3 (S-120 T / m, upper twist). A core yarn was formed by twisting. Next, 14 core yarns obtained were twisted at a twist number of S-60 T / M to obtain a rope core.
On the other hand, a sheath yarn was formed under the same conditions as in Example 1.
Using the obtained two sheath yarns, the periphery of the rope core portion made of only PET was covered with S-60T / M to form a rope sheath portion. One strand was obtained by these rope core part and rope sheath part. Three strands of this strand are twisted at a twist number of Z-25T / M, thereby forming a strand in which the periphery of a rope core portion made of only PET is covered with a sheath portion using a sheath yarn made of a core-sheath structure fiber. A rope having a total rope fineness of 950400 dtex and a rope diameter of 14 mm was obtained. Thereafter, in the same manner as in Example 1, a natural stone connecting member of Comparative Example 2 was obtained.
The ratio of the core-sheath structure fiber covering the periphery of the rope core part and the PET used for the rope core part of the connecting member was core-sheath structure fiber: PET = 12.5: 87.5 (mass% ratio). .
(Comparative Example 1)

A fiber assembly was formed using only PET instead of the core-sheath structure fiber used in Example 1. Other than that was carried out similarly to Example 1, and obtained the sample of the comparative example 1. FIG. That is, the rope core part formed on the core yarn and the rope sheath part formed on the sheath yarn were both made of only PET.
In addition, since the said sample was comprised only by PET unlike the core-sheath structure of Example 1, the heat processing aiming at heat sealing | fusion was not performed.
(Comparative Example 2)

A zinc aluminum alloy plated iron wire having a diameter of 14 mm was used as Comparative Example 2.
Table 1 shows the test results of the natural stone connecting members obtained in Examples 1 to 3 and Comparative Examples 1 and 2.

  As shown in Table 1, since the samples used in Examples 1 and 2 were composed of a fiber assembly including fibers having a core-sheath structure, the heat due to the sheath component was formed on the outer periphery of the fiber assembly due to the heat fusion effect. As a result of the provision of the fusion layer, the adhesive did not penetrate into the fiber assembly. That is, since the sample used in Examples 1 and 2 contained 20% by mass or more of fibers having a core-sheath structure in the fiber assembly, the fiber assembly and natural stone were firmly bonded with an adhesive. It was. On the other hand, the sample used in Example 3 contained fibers having a core-sheath structure, but the content in the fiber assembly was not 20% by mass or more, so the heat fusion effect by the sheath component was satisfactory. However, it was not as much as in Examples 1 and 2. As a result, the adhesive slightly penetrated into the fiber assembly, and a temporary adhesion performance with natural stone was exhibited.

  Moreover, since Examples 1-3 did not use a metal material, the strength reduction as a connecting member due to rust did not occur. Therefore, the safety factor as a connecting member before and after the weather resistance test was 1.1 or more, and the tensile strength was sufficiently maintained.

  Since the comparative example 1 was comprised with the fiber assembly instead of the metal material, the strong fall as a connection member by rust did not arise. Therefore, the safety factor as the connecting member before and after the weather resistance test was 1.1 or more, and the tensile strength was sufficiently maintained. However, because it did not contain any fibers having a core-sheath structure, a heat-sealing layer of a sheath component was not provided on the outer periphery of the fiber assembly due to the heat-sealing effect, so that the adhesive penetrated significantly inside the fiber assembly. As a result, the natural stone and the sample were not adhered at all.

  Since the sample used in Comparative Example 2 was a metal material, there was no penetration of the adhesive into the metal. For this reason, the adhesive force between the natural stone and the metal material was sufficiently maintained. However, rust was generated in the metal material during the weather resistance test, and the metal material was corroded due to this, so that the safety factor as a connecting member was 1.1 or less, and the strength was significantly reduced.

  Based on the above, it was confirmed that Examples 1 to 3 sufficiently satisfy the effects of the present invention.

  According to the present invention, a block that generates carbon dioxide when producing concrete as a raw material is used as a civil engineering structure that protects a coastal area from floods during heavy rains / increases in water and high waves during bad weather in rivers, coasts, riverbanks, etc. Rather than using natural stone, and using a specific fiber assembly that does not rust even when laid in water as a connecting member for connecting natural stones, it is necessary as a connecting member even when laid in water It is possible to provide a natural stone connecting member having sufficient tensile strength, strength, and adhesion with natural stone.

An example figure of the connection method using the natural stone connection member in this invention An example figure of a hook type natural stone connecting member in the present invention An example figure of the connection method using the hook-shaped natural stone connection member in this invention An example figure of the connection method using the loop type natural stone connection member in this invention

Explanation of symbols

1: Natural stone
2: Natural stone connecting member (fiber assembly)
3: Recess 4: Adhesive
5: Heat fusion part 6: Hook-like fiber aggregate 7: Loop-shaped fiber aggregate

Claims (3)

  A member that connects a plurality of natural stones, and is composed of a fiber assembly including a fiber having a core-sheath structure in which a sheath having a lower melting point than that of the core is provided around the core. A natural stone connecting member, wherein the sheath portion of the aggregate is heat-sealed.   2. The natural stone connecting member according to claim 1, wherein both the core and the sheath of the fiber having a core-sheath structure are a polyester polymer.   A concave portion is formed in each of the natural stones connected to each other, and the natural stone connecting member according to claim 1 is partially inserted into the concave portion of each natural stone and bonded within the concave portion. A natural stone connection structure characterized by being fixed by an agent.

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