JP2010106510A - Method for joining concrete products together, and press-fit member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for joining concrete products which can further enhance water sealing performance between the concrete products by effectively exerting elasticity belonging to an adhesive. <P>SOLUTION: In the method for joining box culverts 100, an adhesive surface area 3 is determined by an elastic body 2 the surface of which serves as skin layers 21b and 22b disabling the adhesion of the adhesive 4 on a joint surface 1 for being coated with the adhesive 4. Furthermore, a boundary of the adhesive surface area is limited by the elastic body 2 and the joint surface 1 facing the box culvert 100 with the determined adhesive surface area 3, and the adhesive surface area with the defined boundary is filled with the adhesive 4, so that the box culverts 100 can be joined to each other. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a method for joining concrete products for maintaining the joining between concrete products after construction in sewers, drainage channels, joint grooves, etc., which are structures constructed by precast concrete products such as box culverts. is there.

Conventionally, when joining concrete products, what joins concrete products using an adhesive agent is also known (patent document 1). In this patent document 1, an adhesive pack that separates and stores the main agent and the curing agent is removed, and a member that separates the main agent and the curing agent is removed at the time of joining, and the adhesive agent pack is sandwiched between the main agent and the curing agent. In this configuration, the adhesive is mixed and the adhesive is squeezed out from the adhesive pack and applied to the joint surface, and then the concrete products are joined to each other on the joint surface where the adhesive is applied.
Has been proposed (see, for example, Patent Document 1).

On the other hand, there is also disclosed one using an adhesive having elasticity when joining concrete products (see, for example, Patent Document 2). Specifically, by filling the space surrounded by the elastic body and the concrete product itself with an adhesive and joining the concrete products together, it can be cured without leaking the adhesive and between the concrete products. The thing which improved the water-stopping property greatly is also disclosed (for example, refer patent document 2).
JP-A-10-292506 JP 2007-314965 A

  Here, the thing of patent document 2 implement | achieves the stable water-stop by making the adhesive which has elasticity with respect to the elastic deformation of an elastic body suitably also because an elastic body and an adhesive fasten at the time of construction. ing. At present, the adhesive having elasticity has improved its performance, and the present situation is that an adhesive having a higher elasticity than the material used as the elastic body can be effectively used for joining concrete products. That is, from now on, what can further improve the water-stopping property between concrete products by more effectively exerting the elasticity of the adhesive having such elasticity is required.

  This invention pays attention to such a malfunction, and provides the joining method of the concrete product which can exhibit the elasticity which an adhesive agent has more effectively, and can further improve the water stop between concrete products.

  In order to achieve such an object, the present invention takes the following measures. That is, the method for joining concrete products according to the present invention is a method for joining concrete products in which at least two concrete products having joint surfaces at opposite ends are joined by applying an elastic adhesive to the joint surfaces. A method in which a bonding surface area is defined by an elastic body having a skin layer on which the adhesive cannot be bonded to a bonding surface to which an adhesive is applied, and the concrete product is opposed to the concrete product in which the bonding surface area is determined The boundary of the adhesive surface region is limited by the joint surface and the elastic body, and an adhesive is filled in the adhesive surface region where the boundary is limited to bond the concrete products together.

  If it is such, it will become the structure which the adhesive agent which has elasticity contacts an elastic body through a skin layer. Therefore, the elastic body and the adhesive can be brought into contact with and separated from each other. By doing so, when a concrete product contacts and separates, an elastic body and an adhesive agent can expand and contract independently, respectively. Therefore, it is possible to avoid the expansion / contraction of the adhesive from being interfered with by the expansion / contraction range of the elastic body. As a result, the elasticity of the adhesive can be exhibited more effectively, and the water stoppage between the concrete products can be further improved.

  As a specific configuration of the elastic body, the skin layer may be formed on the surface of the elastic body by molding the elastic body by extrusion to form a bubble-free layer.

  And in order to make the positioning of the elastic body relative to the concrete product suitable and to ensure the filling of the adhesive, a concave portion having a groove shape for attaching the elastic body is provided on one or both of the joint surfaces. Is desirable.

  And in order to make it easy for the elastic body and the adhesive to perform independent expansion and contraction, the concave portion is provided with an attachment step portion for attaching the elastic body, and the attachment step portion is provided with an adhesive provided at a position through the step. It is preferable to have a filling step for filling.

  In general, adhesives such as high-elastic adhesives exhibit higher stretchability than materials used as elastic bodies. Therefore, the concave part is formed deeper than the filling step part, and the thickness of the adhesive is determined. Is preferably made relatively small, and this configuration can further clarify the mounting position of the elastic body.

And this invention is based on the said requirements, the outer surface elastic body which attached the adhesion surface area | region to the joint surface of the concrete product in the U shape, and the cyclic | annular or U shape attached to the inner side of the said outer elastic body As a U-shape defined by the inner elastic body, an adhesive is injected from one end of the U-shaped adhesive surface region, and the adhesive is press-fitted until the adhesive reaches the other end. It is supposed to be. Therefore, the adhesive surface area is made U-shaped and the end of the adhesive surface area is opened, so that the end of the adhesive surface area is opened at the time of joining compared to the case where the adhesive surface area is closed, and the internal pressure of the adhesive surface area is increased. Can be prevented. (Embodiment: It is possible to press-fit the adhesive without separately processing the concrete product for injection. The work of press-fitting the adhesive can be completed only by press-fitting from one place.)
Then, as a specific aspect in the case of applying such a joining method to a so-called precast concrete product such as a box culvert or a water channel having a pair of side plates and a bottom plate continuous to the pair of side plates, an adhesive is applied to one of the side plates. A mode in which the adhesive is press-fitted from the upper end of the side plate to the upper end of the other side plate can be exemplified. By doing so, since the press-fitting of the adhesive can be completed only by the work from the upper side of the concrete product, the safety during the work can be effectively improved. In particular, it is possible to effectively avoid such a problem that an operator is forced to work in a narrow place for the press-fitting work of an adhesive, which is seen when applied to a concrete product having a small size.

  As a technique for press-fitting the adhesive more reliably and quickly, there can be mentioned a technique of press-fitting the adhesive with the press-fitting member inserted downward from the upper end of one side plate.

  And in order to press-fit the adhesive reliably and promptly, it is desirable to set the viscosity when using the adhesive to 10,000 mPa · s or less. Specifically, it is preferable to use a two-component adhesive of an epoxy resin and a modified silicone resin as an adhesive having not only such a viscosity but also an adhesive performance and elasticity suitable for the above-described embodiment. In addition, when using an adhesive, the performance of the same adhesive varies depending on the temperature at which it is used. Therefore, as described in detail in the examples below, the adhesive may be selected from several types depending on the temperature. Is preferred.

  Then, the press-fitting member according to the present invention can be suitably applied to the case where the adhesive is injected from one end of the U-shaped adhesive surface region and the adhesive is press-fitted until the adhesive reaches the other end. Is characterized in that the adhesive is inserted from the upper end of one side plate and the adhesive is press-fitted until the adhesive reaches the upper end of the other side plate. As a specific configuration of such a press-fitting member, there can be mentioned one in which a tubular member is passed through an elastic body and a hose capable of injecting an adhesive is connected to one end side of the penetrated tubular member.

According to the present invention, it is possible to effectively avoid adhesion of the elastic body and the adhesive and to make contact and separation. By doing so, when a concrete product contacts and separates, an elastic body and an adhesive agent can expand and contract independently, respectively. Therefore, it is possible to avoid the expansion / contraction of the adhesive from being interfered with by the expansion / contraction range of the elastic body. As a result, the elasticity of the adhesive can be exhibited more effectively, and the water stoppage between the concrete products can be further improved.

  Further, according to the press-fitting member according to the present invention, the adhesive can be press-fitted from an arbitrary place, so that the adhesive can be filled more safely and reliably and more quickly.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  In this embodiment, a case in which an underground structure 200 such as a sewer is constructed using a box culvert 100 as a concrete product will be described. Specifically, this underground structure 200 connects a plurality of box culverts 100 via an elastic body 2, an adhesive 4, and a joint portion 5.

  In this embodiment, the box culvert 100 has a pair of side plates 100a, a bottom plate 100b continuous to the pair of side plates 100a, and a top plate 100c positioned opposite to the bottom plate 100b. It is a form and is provided with the joint surfaces 1 at both ends in the longitudinal direction, and a plurality of the joint surfaces 1 are joined together at the joint surface 1 to construct the underground structure 200. The joint surface 1 has a square outer peripheral shape and a substantially square inner peripheral shape, and has a quadrangular annular shape. In this embodiment, the concrete product having a rectangular tube shape is described as shown in the figure. Of course, in order to form a three-sided water channel by a concrete product that is constituted by a pair of side plates 100a and a bottom plate 100b and whose upper side is opened. The present invention may be applied.

  Here, in the method for joining the box culvert 100 as the concrete product according to the present invention, at least two of the box culverts 100 having the joint surfaces 1 at both ends facing each other, and the adhesive 4 having elasticity on the joint surface 1 are provided. It is a method for joining concrete products that are applied and joined, and in the joining surface 1 to which the adhesive 4 is applied, the adhesive surface region 3 is formed by an elastic body 2 having skin layers 21b and 22b on which the adhesive 4 cannot adhere. The boundary of the adhesive surface region is limited by the joint surface 1 and the elastic body 2 facing the box culvert 100 in which the adhesive surface region 3 is defined, and the adhesive 4 is filled in the adhesive surface region where the boundary is limited. The box culverts 100 are joined to each other.

  Note that the connection method according to the present embodiment is to press-fit the adhesive 4 from one specific place using the press-fitting member 6, and this method will be described in detail later.

  Hereinafter, the joining method of the joining surface 1 of the box culvert 100 will be described in detail together with the description of the configuration of each part.

  As shown in FIGS. 1, 2, 4, and 5, the joint surface 1 is formed at both ends in the longitudinal direction of the box culvert 100, and the elastic body 2 is attached to one joint surface 1. Thus, the uneven surface 10 that can specify the bonding surface region 3 is used, and the other bonding surface 1 is a flat surface 11 that is formed flat except for the configuration related to the joint portion 5 described later.

  The concave / convex surface 10 forms a concave portion 12 having a groove shape for positioning the elastic body 2 and the adhesive 4. 1 and 2, the concave portion 12 circulates around the first packing material 21 (to be described later) formed in a U shape along the side plate 100a and the bottom plate 100b of the box culvert 100 and the periphery of the box culvert 100. The mounting step portion 13 to which the elastic body 2 is attached and the attachment step portion 13 is filled with the adhesive 4 provided at a position through the step. And a slope 15 formed adjacent to the mounting step 13 and the filling step 14.

  As shown in FIGS. 4 and 5, the mounting step portion 13 is formed so that the elastic body 2, specifically, a first packing material 21 and a second packing material 22 described later are positioned through a certain distance. It is a thing. Inclined surfaces 15 that act as a so-called draft when the box culvert 100 is manufactured are formed at both ends by inclining in the direction in which the mounting step 13 is expanded.

  As shown in FIGS. 4 and 5, the filling step portion 14 is joined to the mounting step portion 13 by a step, that is, a filled adhesive 4 provided at a relatively shallow position via the inclined surface 15. Part. That is, since the mounting step portion 13 is formed at a position deeper than the filling step portion 14, the dimension in the joining direction between the elastic body 2 and the filled adhesive 4 is the dimension of the elastic body 2. Is set larger. In the present embodiment, the upper portion of the second packing material 22 on the top plate 100c side is also shallowly formed from the mounting step 13 via the inclined surface 15, but the detailed illustration of such a configuration is shown. Omitted.

  As shown in FIGS. 1 to 5, the elastic body 2 is integrally formed with a nonpolar resin such as polyethylene or polypropylene, which is attached to the uneven surface 10 along the above-described attachment step portion 13. . Specifically, as shown in FIG. 3, by forming by extrusion, skin layers 21b and 22b that do not allow bubbles b to exist are provided on the surface, and cavities 21a and 22a are formed in the center. It has become.

  And the elastic body 2 has the 1st packing material 21 which is the outer side elastic body 2, and the 2nd packing material 22 which is the inner side elastic body 2, as shown in the figure. The first packing material 21 is positioned in the outermost U shape of the joint surface 1, and the upper end is configured to protrude slightly from the surface of the top plate 100 c. The second packing material 22 is formed in an annular shape by circling slightly inward of the first packing material 21 also on the top plate 100c side.

  As shown in FIGS. 1, 2, 4, and 5, the bonding surface region 3 is the bonding surface 1 in the bonding direction of the box culvert 100, specifically, the filling step 14 of the flat surface 11 and the uneven surface 10. In the surface direction of the joint surface 1, the elastic body 2, that is, the first packing material 21 and the second packing material 22, specifically defined by the skin layers 21 b and 22 b, is generally U-shaped. It refers to a quadrangular columnar space communicating with each other while being bent or bent. Since the adhesive 4 filled in the adhesive surface region 3 cannot adhere to the skin layers 21b and 22b provided on the elastic body 2, it can constitute a two-sided adhesive state that contacts only the joint surface 1. It has become a thing.

  The adhesive 4 is, for example, a highly elastic adhesive 4. In this embodiment, the adhesive 4 is mixed with an epoxy resin excellent in adhesive performance and a modified silicone resin excellent in stretchability and weather resistance. The two-component adhesive 4 is used. And the adhesive 4 used in this embodiment, by properly using the three types of adhesive 4 depending on the temperature at the time of construction, the viscosity according to JIS K 6833 is always 10,000 mPa · s or less, pot life 20 minutes or more, In addition, the touch curing time is set to satisfy all the conditions of 6 hours or less, and the adhesive 4 will be described in detail later.

  As shown in FIGS. 1, 2, 4, and 5, the joint portion 5 is for joining the box culverts 100 without shifting in the joining direction, and is embedded in the vicinity of the four corners of the joining surface 1. By setting the both ends of the joint bar 52 to the socket 51, the joint surfaces 1 can be accurately joined. That is, as shown in FIGS. 4 and 5, the box culvert 100 joined by the joint portion 5 is provided on the joint surface 1 by suitably prohibiting relative movement in the surface direction of the joint surface 1. The elastic body 2 and the adhesive 4 will expand and contract in a direction substantially along the joining direction.

  Therefore, in this embodiment, as shown in FIGS. 4 and 5, the skin layers 21 b and 22 b described above are provided on the surfaces of the first packing material 21 and the second packing material 22 that are the elastic bodies 2. 5, the adhesive 4 cannot be bonded to the skin layers 21 b and 22 b of the elastic body 2 and is separated from the skin layer 21 b and 22 b, and is bonded to only two surfaces of the joint surface 1 facing the box culvert 100. . Therefore, in the drawing, the adhesive 4 can be extended larger than the size of the elastic body 2 without being restricted by the range in which the elastic body 2 expands and contracts.

  And as for the joining method which concerns on this embodiment, the one end part of the U-shaped adhesion surface area | region 3 located in the upper end of one side plate 100a as a method of apply | coating the adhesive agent 4 to the above-mentioned adhesion surface area | region 3 The adhesive 4 is press-fitted until the adhesive 4 reaches the other end, that is, the upper end of the side plate 100a. Specifically, a method is adopted in which the adhesive 4 is press-fitted from such one point, with the press-fitting member 6 shown in FIG. 6 inserted from the upper end of one side plate 100a.

  As shown in FIG. 6, the press-fitting member 6 includes an aluminum pipe 61 which is a tubular member having a length of 20 cm, for example, and a pipe insertion of an elastic insertion portion 63 having a length and length of about 15 cm having the same material and dimensions as the elastic body 2 described above. A vinyl hose BH for injecting the adhesive 4 through the binding band 62 is attached to one end of the aluminum pipe 61 that is inserted and penetrated into the hole 63a and then penetrated. In addition, the press-fitting member 6 is provided with an adhesive portion 61a secured to the distal end and the proximal end of the elastic insertion portion 63 via, for example, a double-sided tape.

  Then, as shown in FIGS. 7 and 8, the adhesive 4 is injected with the press-fitting member 6 inserted from one end of the adhesive surface region 3 until the adhesive 4 reaches the other end. 4 is press-fitted. Further, in the present embodiment, finally, the adhesive 4 is also applied to the upper side of the second packing material 22 attached to the top plate 100c, thereby completing the joining operation of the box culvert 100 by the adhesive 4. .

  By adopting the configuration as described above, the bonding method of the concrete product according to the present embodiment defines the bonding surface region 3 by the elastic body 2 having the skin layers 21b and 22b on which the adhesive 4 cannot adhere. Since the box culverts 100 are bonded together by filling the adhesive 4, it is possible to effectively avoid the adhesion between the elastic body 2 and the adhesive 4, and to be able to contact and separate. . By doing so, when the box culverts 100 are brought into contact with each other, the elastic body 2 and the adhesive 4 can expand and contract independently. Therefore, the expansion / contraction of the adhesive 4 can be prevented from being interfered with the expansion / contraction range of the elastic body 2. As a result, the elasticity of the adhesive 4 can be exhibited more effectively, and the waterstop between the box culverts 100 can be further improved.

  In the present embodiment, the skin layers 21b and 22b are formed by extruding the elastic body 2 to form a layer without bubbles b on the surface of the elastic body 2, for example, on the surface of the elastic body 2. The skin layers 21b and 22b are realized with a simple configuration by effectively avoiding the formation of a body film.

  Further, in the present embodiment, the elastic body 2 is attached to one joint surface 1 of the box culvert 100 in order to make the positioning of the elastic body 2 relative to the box culvert 100 suitable and ensure the filling of the adhesive. For this purpose, a recess 12 having a groove shape is provided.

  In order to make the elastic body 2 and the adhesive 4 easily expand and contract independently from each other, in this embodiment, the recess 12 has a step difference between the mounting step portion 13 to which the elastic body 2 is attached and the mounting step portion 13. A filling step 14 for filling the adhesive 4 provided at the interposed position is formed.

  In general, the adhesive 4 such as the high-elasticity adhesive 4 exhibits higher stretchability than the material used as the elastic body 2, and therefore, in this embodiment, the recessed portion 12 is provided with the mounting step portion 13 rather than the filling step portion 14. The thickness of the adhesive 4 is relatively small.

  In this embodiment, the adhesive surface area 3 is defined as a U-shape, and the adhesive 4 is injected from one end of the U-shaped adhesive surface area 3, that is, from the upper end of one side plate 100 a. The adhesive 4 is press-fitted until the adhesive 4 reaches the other end, that is, the upper end of the other side plate 100a.

  In this way, the adhesive surface region 3 is U-shaped and the end of the adhesive surface region 3 is opened, so that the end of the adhesive surface region 3 is opened at the time of bonding as compared to the case where the adhesive surface region 3 is closed. An increase in the internal pressure in the region 3 can be prevented. Further, by forming the adhesive surface region 3 communicated in a U-shape, it is possible to press-fit the adhesive 4 into the box culvert 100 without performing any special processing for injecting the adhesive 4 It is said. In particular, the adhesive 4 press-in operation can be completed only by press-in from one place on the upper side of the box culvert 100. Therefore, since the operator can complete the press-fitting of the adhesive 4 only by the work on the upper side of the box culvert 100, the safety during the work can be effectively improved. Such an improvement in workability is a problem that the operator is forced to work in a narrow place for the press-fitting work of the adhesive 4 as seen particularly when applied to the box culvert 100 having a small size. It can be effectively avoided.

And in this embodiment, since it employ | adopted the method of pressing-in the adhesive 4 in the state which inserted the press-fit member 6 downward from the upper end of one side plate 100a, it is reliable and quick. In addition to realizing filling, it contributes to a safer method for joining concrete products.
<Modification>
Then, the modification of this embodiment is demonstrated. In addition, about this modification, while attaching | subjecting the same code | symbol to the same component as the said embodiment, the detailed description shall be abbreviate | omitted.

  In this modification, as shown in FIGS. 9 and 10, the concave and convex surfaces 12 having a groove shape for attaching the elastic body 2 are formed by providing the concave and convex surfaces 10 on both the joint surfaces 1 provided at both ends of the box culvert 100. It is assumed that it was provided. That is, the mounting step portion 13, the filling step portion 14, and the inclined surface 15 described in detail in the above embodiment are formed on both of the facing joint surfaces 1.

  And by such a structure, the elastic body 2 will be positioned reliably from both directions of joining. Also, as shown in FIG. 10, since the adhesive 4 cannot adhere to the skin layers 21b and 22b as in the above embodiment, the adhesive 4 can extend without being interfered with the elastic body 2. Yes.

  Although the embodiment of the present invention has been described above, the specific configuration of each part is not limited to the above-described embodiment and modifications, and various modifications can be made without departing from the spirit of the present invention. is there. For example, in the above-described embodiment, the skin layer is formed by extrusion molding at the time of manufacturing the elastic body, but of course, the skin layer may be realized using a separate body from the elastic body. For example, the surface of the elastic body may be coated with a separate film or wound.

  In addition, the specific configuration of each part is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

Examples of the present invention are shown below, but the present invention is not limited to the examples.

  In this embodiment, the adhesive is a so-called high-elastic adhesive, and is a two-part liquid mixture formed by mixing an epoxy resin excellent in adhesive performance and a modified silicone resin excellent in stretchability and weather resistance. It is assumed that an adhesive is used. The adhesive 4 used in the present embodiment has a viscosity according to JIS K 6833 of 10,000 mPa · s or less, a pot life of 20 minutes or more, and by using three types of adhesives depending on the temperature at the time of construction. The touch curing time is set to satisfy all the conditions of 6 hours or less.

  The adhesives that can be applied to the present invention are shown as “for winter”, “for general use”, and “for summer”. Specifically, these adhesives are made of two liquids in which an epoxy resin and a modified silicone resin are mixed. In this embodiment, by changing the type of the catalyst as appropriate, as described later, adhesion of “summer”, “winter”, and “general” exhibiting the characteristics shown in FIGS. 11 to 13. It is used as an agent. Note that the “winter” adhesive particularly uses a diluent to reduce the viscosity.

  11 to 13, the viscosity, visible time, and finger touch curing time at each temperature condition were measured for these three types of adhesives.

  FIG. 11 shows the measured viscosities of these three types of adhesives. Specifically, in a method according to JIS K 6833 “General adhesive test method 6.3 Viscosity”, a BH viscometer was used and the rotation speed was 20 rpm.

  FIG. 12 is a measurement of the pot life of these three types of adhesives. Specifically, 300 g of each of the three types of adhesives was used as a sample, and the pot life was specified by measuring the temperature at the center with time.

FIG. 13 shows the measurement of the finger touch curing time of these three types of adhesives. Specifically, using an RCI-type drying time measuring device (drying recorder), the time when the secondary linear mark disappearance point was determined to be the end of curing, and it was defined as the finger touch curing time. Further, the data shows the data when the adhesive application thickness is 0.5 mm.
And in order to press-fit the adhesive reliably and promptly, it is desirable that the viscosity at the time of use of the adhesive is set to 10,000 mPa · S or less. Specifically, it is preferable to use a two-component adhesive in which an epoxy resin and a modified silicone resin are mixed as an adhesive having not only such viscosity but also adhesive performance and elasticity suitable for the above-described embodiment. In addition, when using an adhesive, the performance of the same adhesive varies depending on the temperature at which it is used. Therefore, as described in detail in the examples below, the adhesive may be selected from several types depending on the temperature. From the above adhesives, it was possible to specify an adhesive satisfying the above conditions for each measured temperature. Specifically, when the temperature is 5 ° C., only “for winter” satisfies all the required characteristics. At 10 ° C. and 20 ° C., “winter use” and “general use” satisfy all the required characteristics. At 30 ° C., only “general use” satisfies all the required characteristics. At 40 ° C., only “summer” satisfies all the required characteristics.

  As described above, in the present embodiment, the present invention can be suitably implemented even in various situations by applying an appropriate adhesive according to a change in temperature from a plurality of types of adhesives having different characteristics. Prove that.

The external view which shows the underground structure which concerns on one Embodiment of this invention. The front view which shows the box culvert concerning the embodiment. Explanatory drawing which shows the elastic body which concerns on the same embodiment. Sectional drawing of the principal part of the box culvert concerning the embodiment. FIG. 5 is an operation explanatory diagram according to FIG. 4. Explanatory drawing which shows the press-fit member which concerns on the same embodiment. Action | operation explanatory drawing which concerns on the same embodiment. Other operation explanatory drawing concerning the embodiment. Sectional drawing of the principal part of the box culvert which concerns on the modification of the embodiment. Action explanatory drawing which concerns on FIG. The figure which shows the graph which concerns on the Example of this invention. The figure which shows the other graph which concerns on the same Example. Same as above.

Explanation of symbols

100 ... Concrete product (box culvert)
DESCRIPTION OF SYMBOLS 100a ... Side plate 100b ... Bottom plate 1 ... Joining surface 12 ... Recessed part 13 ... Mounting step part 14 ... Filling step part 2 ... Elastic body 21 ... Outer elastic body (1st packing material)
22 ... Inner elastic body (second packing material)
21b, 22b ... skin layer 3 ... adhesive surface area 4 ... adhesive 6 ... press-fitting member

Claims (13)

A method for joining concrete products, in which at least two concrete products having joint surfaces at opposite ends are joined by applying an adhesive having elasticity to the joint surfaces,
The adhesive surface area is defined by an elastic body having a skin layer on which the adhesive cannot be bonded to the bonding surface where the adhesive is applied,
The boundary of the adhesive surface area is limited by the joint surface and the elastic body of the concrete product facing the concrete product for which the adhesive surface area is defined,
A method for joining concrete products, in which an adhesive is filled in an adhesive surface area having a limited boundary to join concrete products together. The method for joining concrete products according to claim 1, wherein the skin layer is formed on the surface of the elastic body by forming the elastic body by extruding to form a bubble-free layer. The method for joining concrete products according to claim 1 or 2, wherein a concave portion having a groove shape for attaching the elastic body is provided on one or both of the joining surfaces of the concrete products. The said recessed part shall have the attachment step part which attaches the said elastic body, and the said attachment step part has the filling step part for filling with the said adhesive agent provided in the position through the level | step difference. Or the joining method of the concrete products of 3. The method for joining concrete products according to claim 4, wherein the recess is formed deeper in the attachment step than in the filling step. The bonding surface area is defined in a U shape by a U-shaped outer elastic body attached to the joint surface of the concrete product and an annular or U-shaped inner elastic body attached inside the outer elastic body. ,
6. The method for joining concrete products according to claim 5, wherein an adhesive is injected from one end of the U-shaped adhesive surface region and the adhesive is press-fitted until the adhesive reaches the other end. . The concrete product has a pair of side plates and a bottom plate continuing to the pair of side plates,
The method for joining concrete products according to claim 6, wherein the adhesive is pressed into the adhesive from the upper end of one side plate until the adhesive reaches the upper end of the other side plate. The method for joining concrete products according to claim 7, wherein the adhesive is press-fitted with a press-fitting member inserted downward from the upper end of the one side plate. The method for joining concrete products according to claim 6, 7 or 8, wherein the viscosity at the time of use of the adhesive is set to 10,000 mPa · S or less. The method for joining concrete products according to claim 9, wherein the adhesive is a two-part adhesive of an epoxy resin and a modified silicone resin. The method for joining concrete products according to claim 9 or 10, wherein the adhesive is selectively used depending on the temperature. It is used for the method for joining concrete products according to any one of claims 6 to 11,
A press-fitting member, wherein the adhesive is inserted from the upper end of one side plate and the adhesive is press-fitted until the adhesive reaches the upper end of the other side plate. The press-fitting member according to claim 12, wherein a tubular member is passed through the elastic body, and a hose is connected to one end side of the penetrated tubular member by a binding band.