JPH1058426A - Usage of water-expansible seal packing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a usage of a water-expansible seal packing which absorbs water and expands sufficiently and which is excellent in form maintaining properties (creep resistance) even after absorption of water. SOLUTION: A water-expansible seal packing 1 constituted of a rubber composition containing a rubber and a water-absorbing resin is fitted on the periphery of an injection hole pipe 2 to be buried in a concrete segment, and it is used on the occasion when the concrete segment is prepared by setting a hydraulic setting cement material in a state of the injection hole pipe 2 being buried.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of using a water-swellable seal packing which absorbs moisture, expands sufficiently, and has excellent shape retention (creep resistance) even after absorbing water. Is a concrete segment used when making a tunnel or the like, and is mounted around a concrete injection pipe buried in the concrete segment, even if it is high-pressure groundwater,
The present invention relates to a method of using a water-swellable seal packing that can be effectively waterproofed.

[0002]

2. Description of the Related Art In recent years, tunnels have been made by a shield method from the viewpoints of shortening the construction period and safety. However, the tunnel itself is composed of a concrete pipe composed of a plurality of arc-shaped concrete segments. . That is, such a concrete pipe is used in the shield method.
A plurality of concrete segments are connected by bolts, and then hydraulic cement material is poured from an injection hole pipe buried in the concrete segments to shield and fix the concrete segments from the surroundings.

Here, a concrete segment used for a concrete pipe is generally prepared by placing an injection hole pipe in a predetermined position of the concrete segment frame beforehand.
It is made by pouring hydraulic cement material.

[0004] However, with the shrinkage of the hydraulic cement material, a gap is easily formed between the molded concrete segment and the injection pipe, and the gap is transmitted from the outside of the concrete pipe to the inside of the concrete pipe, That is, there is a problem that groundwater or the like enters the tunnel.

Therefore, a gap between the concrete segment and the injection hole pipe is formed after the concrete segment is molded.
It was common practice to repair using a putty for repair or a sealant.

[0006] However, such an operation is costly and labor-intensive, takes time to cure the repair putty and the sealing agent, and furthermore, the size of the gap between the concrete segment and the injection hole pipe becomes longer with time. However, there is a problem that groundwater intrusion cannot be sufficiently prevented by repairing with a putty for repair or a sealant.

[0007] Therefore, it has been attempted to mount a so-called O-ring on the injection hole pipe in advance and make a concrete segment therefrom.

However, it is difficult to uniformly compress the O-ring because the size of the gap between the concrete segment and the injection hole pipe is not uniform, and the O-ring is generally planar. In addition, when installed in an injection hole pipe, there was a problem that the waterproof distance in the length direction of the pipe was short, and the effect of preventing groundwater intrusion was poor.

On the other hand, when an O-ring is used,
On the contrary, the rebound resilience of the ring causes a problem that the gap between the concrete segment and the injection hole pipe tends to be large, and as a result, there is also a problem that the waterproof effect is not improved at all.

On the other hand, in the field of household and sanitary articles such as diapers and sanitary articles for children, water-absorbing resins are frequently used. Although the water-absorbing resin is generally made of polyacrylic acid or the like, it has poor creep resistance, and has a problem that its shape is easily deformed particularly in a water-absorbing state.

That is, the conventional water-absorbent resin temporarily absorbs water and expands to provide a waterproof effect, but is easily creep-deformed due to the pressure between the concrete segment and the injection hole pipe and high-pressure groundwater. Even if used as it is, a long-term waterproofing effect could not be obtained.

[0012]

SUMMARY OF THE INVENTION Accordingly, the present invention solves the conventional problems, absorbs water and absorbs water sufficiently, and has excellent shape retention (creep resistance) even after water absorption. It is intended to provide a method of using a seal packing.

More specifically, for example, the hydraulic cement material is mounted around an injection hole pipe buried in a concrete segment used for making a tunnel or the like, and the hydraulic cement material is buried in a state where the injection hole pipe is buried. The method of using the water-swellable seal packing used when making the concrete segment by curing it, and furthermore, using the concrete segment with the water-swellable seal packing attached, effective waterproofing of groundwater and the like is possible. Another object of the present invention is to provide a method of using a water-swellable seal packing.

[0014]

According to the present invention, a water-swellable seal packing made of a rubber composition containing rubbers and a water-absorbent resin is mounted around an injection hole pipe buried in a concrete segment. A method of using a water-swellable seal packing, which is used when a hydraulic cement material is hardened in a state in which an injection hole pipe is buried to form the concrete segment.

[0015] The method of using the water-swellable seal packing includes a water-swelling pipe that is provided with the water-swellable seal packing and that uses a concrete segment embedded therein to effectively waterproof groundwater and the like. It also includes the method of using the conductive seal packing. Hereinafter, the present invention will be described in detail by dividing into components and the like.

(Rubbers) In the present invention, rubbers are mainly used for imparting a function as an elastic body to the water-swellable seal packing. That is, for example, when used in the gap between the concrete segment and the injection hole pipe, it is easily compressed and deformed, and can be easily attached to the slight gap between the concrete segment and the injection hole pipe. By using the elastic force of rubbers, it is tightly fixed at a predetermined position in the gap between the concrete segment and the injection hole pipe, and follows the uneven gap sufficiently to obtain an excellent waterproof effect from the beginning.

Even when the water-absorbent resin absorbs water inside the rubber, the rubber mainly maintains a certain shape, thereby uniformly and effectively exerting a force based on the water absorption to the outside. Then, even after absorbing water, the water-swellable seal packing is tightly fixed to the gap between the concrete segment and the injection hole pipe, and as a result, an excellent waterproof effect is obtained over a long period of time. That is, the water-swellable seal packing of the present invention,
The water-absorbent resin can be regarded as having a structure in which the water-absorbent resin is uniformly surrounded by a so-called rubber elastic band.

Here, the kind of rubbers is not particularly limited, but natural rubber, isoprene rubber, butyl rubber, nitrile rubber, hydrogenated nitrile rubber, acrylic rubber, NBR, chloroprene rubber, ethylene-propylene rubber, EPDM Styrene-butadiene rubber, styrene-butadiene-styrene block polymer, styrene-
Isoprene-styrene block polymer, styrene-ethylene-butylene-styrene block polymer, urethane rubber, silicone rubber, fluorinated rubber, chlorosulfonated polyethylene and the like can be suitably used in the present invention alone or in combination of two or more. .

In particular, natural rubber has good processability and is inexpensive, and isoprene rubber has similar characteristics to natural rubber and more uniform rubber characteristics can be obtained, and is a polar substance such as sodium acrylate. From the standpoint of relatively good compatibility with water-absorbent resins, nitrile rubber, acrylic rubber and NBR
However, from the viewpoint of good water resistance, butyl rubber, hydrogenated nitrile rubber, EPDM, silicone rubber and fluorine-based rubber are styrene-butadiene rubber, styrene- Butadiene-styrene block polymer, styrene-isoprene-styrene block polymer and styrene-ethylene-
Butylene-styrene block polymers are preferred.

A rubber in which natural rubber and chloroprene rubber are blended in a weight ratio of, for example, 90:10 to 50:50 has good weather resistance, high polarity, easy adhesion, and relatively low cost. In this respect, it is suitable for the present invention.

(Crosslinking Agent for Rubbers) In the present invention, in order to improve the shape retention (creep resistance) and mechanical strength of rubbers, it is possible to use a crosslinking agent to increase the molecular weight or three-dimensionally. It is suitable.

The type of the rubber crosslinking agent is not particularly limited. For example, sulfur, sulfur chloride, organic sulfur compounds, organic peroxides, and metal oxides as sulfur-based crosslinking agents can be used. , Tetramethylthiuram disulfide (TMTD), tetramethylthiuram monosulfide (TMTM), dibenzothiazyl disulfide (MBTS), tetraethylthiuram disulfide (T
Phenol-formaldehyde resins represented by ETD), 2-mercaptoimidazoline (EU), bismorpholine disulfide, dipentamethylenethiuram tetrasulfide, quinone dioxime, alkylphenol resin, etc., polythiol compounds, azo compounds and the like can be used. is there.

In particular, from the viewpoint that sulfur-based crosslinking agents are inexpensive and the reaction control is relatively easy, an organic peroxide can provide an excellent crosslinking effect with a small amount of addition, and can be used in TMTD, MBTS and ETM.
U may be used as a cross-linking accelerator in view of easier adjustment of the cross-linking reaction and in obtaining an extremely fast cross-linking reaction. From the viewpoint that the weather resistance of the phenol-formaldehyde-based resin is good, the reaction control is relatively easy, and further, the heat resistance and the creep resistance of the crosslinked rubbers are suitable for the present invention, respectively. It is.

Next, the amount of the rubber crosslinking agent added will be described. That is, in the rubber composition, the rubbers 100
It is preferable to add 0.5 to 5 parts by weight of a rubber crosslinking agent with respect to parts by weight. The amount of rubber crosslinking agent added is
If the amount is less than 0.5 part by weight, the crosslinking effect is poor, and the creep resistance of the rubbers may be inferior. On the other hand, if the amount of the rubber crosslinking agent exceeds 5 parts by weight, the control of the reaction may be prevented. Becomes difficult, or unreacted crosslinking agent remains,
This is because the mechanical strength and heat resistance of the crosslinked rubber may decrease.

Accordingly, from the viewpoint of better balance between the crosslinking effect and the like of the rubber and the reactivity and the like, the amount of the rubber crosslinking agent to be added is 1 to 3 parts by weight with respect to 100 parts by weight of the rubber. Is more preferable.

(Water-absorbing resin) The present invention is characterized in that a water-absorbing resin is used in order to sufficiently and effectively absorb surrounding water. That is, when the water-swellable seal packing of the present invention is used, for example, in a gap between a concrete segment and an injection hole pipe, groundwater that has invaded through the gap is efficiently absorbed by the water-absorbing resin, By expanding, it adheres to the concrete segment and the injection hole pipe, respectively, to prevent the passage of water, and as a result, to prevent water from entering the inside of the concrete pipe.

For example, when the water-swellable seal packing of the present invention is used by being previously attached to an injection hole pipe when producing a concrete segment, the water contained in the hydraulic cement material is absorbed by the water-absorbing material. The resin absorbs and sufficiently closes the gap between the concrete segment and the injection hole pipe by using the water, so that even when the concrete segment is used for the concrete pipe, an excellent waterproof effect is obtained from the beginning. is there.

Here, the kind of the water-absorbing resin used in the present invention is not particularly limited, and for example, a crosslinked product of a neutralized polyacrylic acid, a neutralized self-crosslinked polyacrylic acid , Starch-acrylic acid graft copolymer crosslinked product, starch-acrylonitrile graft copolymer crosslinked product hydrolyzate, vinyl acetate-acrylate copolymer hydrolyzate, acrylate-acrylamide copolymer crosslinked product Product, acrylic acid-2-acrylamide-
A crosslinked product of 2-methylpropanesulfonic acid salt, a crosslinked product of isobutylene-maleic anhydride copolymer, a crosslinked carboxymethylcellulose salt, or polyvinyl alcohol;
Examples include polyvinyl formal, polyvinyl butyral, and crosslinked products thereof. In particular, from the viewpoint of good compatibility with rubbers, a water-absorbing resin comprising a copolymer of a neutralized modified polyacrylic acid is preferred.

Next, the amount of the water-absorbing resin added will be described. That is, it is preferable to add 10 to 40 parts by weight of the water-absorbing resin to 100 parts by weight of the rubber in the rubber composition. If the added amount of the water-absorbing resin is less than 10 parts by weight, the water-absorbing effect and the water-absorbing effect are reduced, and as a result, the waterproof effect of the water-swellable seal packing may be inferior.

That is, more specifically, the rubber composition used for the water-swellable seal packing of the present invention has a weight expansion coefficient (water absorption rate, 23 ° C. temperature) according to JIS K7209 represented by the following formula: It is because it is preferable from the viewpoint of the waterproofing effect that the value of 50% or more, more preferably 60% or more, and optimally 70% or more in the condition) is 50% or more. In order to achieve the above, the amount of the water-absorbing resin to be added is preferably 10 parts by weight or more.

On the other hand, when the amount of the water-absorbing resin added is 4
If the amount exceeds 0 parts by weight, the rate of weight expansion increases, but the proportion of rubbers relatively decreases, and the mechanical properties and creep resistance of the water-swellable seal packing may decrease.

Accordingly, from the viewpoint of better balance between the water absorbing effect and the like and the creep resistance and the like of the water-swellable seal packing, the amount of the water-absorbing resin to be added is 15 to 30 parts by weight based on 100 parts by weight of the rubber. The range of parts by weight is optimal.

(Water Crosslinking Component) In the present invention, the rubber composition preferably contains a water crosslinking component in addition to the rubbers, the rubber crosslinking agent and the water-absorbing resin described above. This is because the creep resistance of the crosslinked rubber alone tends to be insufficient, and it is difficult to obtain long-term shape stability and durability.

More specifically, in the rubber composition used in the present invention, the weight expansion coefficient (23 ° C.) according to JIS K7209 is 50% or more, and
Tensile strength according to JIS K6301 is 4-150
This is because the elongation at break in accordance with Kgf / cm ² and JIS K6301 is preferably 200% or more, and in order to obtain the value and a value in the vicinity thereof, it is more preferable to add a water crosslinking component. .

If the tensile strength of the rubber composition is
If it is less than 4 kgf / cm ² , the mechanical strength of the water-swellable seal packing itself may be inferior. On the other hand, if the tensile strength exceeds 150 kgf / cm ² , the weight expansion coefficient (23 ° C.) is remarkably large. This is because there is a risk that the water-swellable seal packing may be mechanically broken due to expansion of the water-absorbent resin when the breaking elongation is less than 200%.

In the present invention, among the general cross-linking components, a component which cross-links using water is used, which is characterized in that the water-swellable seal packing of the present invention is used for waterproofing. And the compatibility with other resins.

That is, from the viewpoint of improving the compatibility,
The compatibility between rubbers and water-absorbent resins is generally poor, and there has been a problem that large amounts of water-absorbent resins cannot be added to rubbers. To improve the properties of the water-swellable seal packing, such as water absorption.

As the type of the water cross-linking component, any type that can cause a cross-linking reaction by moisture can be suitably used. For example, a combination of a ketiminated polyamide resin and a glycidyl ether compound is preferable. It is.
The reason is that ketimine is hydrolyzed by water, and the generated primary amino group quickly reacts with the glycidyl group of the glycidyl ether compound to form a stable crosslinked structure. On the other hand, in the absence of moisture, the ketimine group of the ketiminated polyamide resin is relatively stable,
This is because of excellent storage stability.

Specific examples of ketiminated polyamide resins are defined as resins derived from polyamide resins and ketones. Further, the amine equivalent of the polyamide resin is preferably in the range of 180 to 250 in consideration of the reactivity with the glycidyl ether compound and the expansion coefficient of the rubber composition obtained.

Here, specific polyamide resins include, for example, those derived from a polymerized fatty acid obtained by heating an unsaturated fatty acid in the presence of a catalyst such as alumina silicate and a polyalkylenepolyamine such as ethylenediamine or diethylenetetramine. Similarly, as specific ketones, diethyl ketone, methyl propyl ketone, methyl isobutyl ketone and the like having 5 to 7 carbon atoms are preferable.

Specific glycidyl ether compounds include compounds obtained by glycidyl etherification of polyether polyol obtained by adding alkylene oxide to polyhydric alcohol, and compounds obtained by glycidyl etherification of polyether polyol obtained by adding alkylene oxide to polyamine. And glycidyl etherified compounds of propylene oxide adduct of propylene glycol (polyoxypropylene glycol).

Next, the amount of the water-crosslinkable component added will be described. That is, in the rubber composition, it is preferable to add 5 to 30 parts by weight of the water-crosslinkable component to 100 parts by weight of the rubber. If the amount of the water-crosslinkable component is less than 5 parts by weight, the water-absorbing effect and the swelling effect are reduced, and as a result, the waterproof effect of the water-swellable seal packing may be inferior. If the amount of ingredients
If the amount exceeds 30 parts by weight, the proportion of rubbers relatively decreases, and the mechanical properties and creep resistance of the water-swellable seal packing may decrease.

Therefore, from the viewpoint of better balance between the water absorbing effect and the like and the creep resistance and the like of the water-swellable seal packing, the amount of the water-crosslinkable component to be added is 10 to 100 parts by weight of rubbers. The range of 20 parts by weight is optimal.

(Other Compounds) In the rubber composition used for the water-swellable seal packing of the present invention, the weight expansion coefficient (water absorption) according to JIS K7209 as a preferable physical property value is 50% or more (23%). ° C), JIS K63
01 to 4-150Kgf / c
m ² , elongation at break according to JIS K6301 is 200
%, It is preferable to further add another composition.

For example, in order to dramatically improve the tensile strength, carbon black is used in an amount of 5 to 40 parts by weight based on 100 parts by weight of rubber. To 100 parts by weight of rubber, 30 to 100 parts by weight, for ease of handling when the rubber composition is processed into a water-expandable seal packing, a softening agent is added to 100 parts by weight of rubber. , 10-4
0 parts by weight, as a crosslinking aid for rubbers, zinc oxide, 3 to 5 parts by weight based on 100 parts by weight of rubbers, 1 to 5 parts by weight of a crosslinking accelerator based on 100 parts by weight of rubbers In order to improve the weather resistance and durability of the rubber composition,
1 to 10 parts by weight per 100 parts by weight of rubber, and 0.5 to 10 parts by weight of stearic acid for 100 parts by weight of rubber for ease of processing the rubber composition Is preferred.

(Form and Usage of Water-Swellable Seal Packing) First, a method of using (water-swelling) seal packing of the present invention will be described. That is, it can be used at any place where a waterproof function is required, such as a tap for a water tap, a packing for a joint of a water pipe, a packing for connecting concrete segments of a side structure, a packing for a water pump, and the like.

However, in consideration of the excellent water absorption, shape retention (creep resistance) and durability of the water-swellable seal packing of the present invention, the water-swellable seal packing is used, for example, for a concrete segment and an injection hole pipe. Used as a putty or sealant in the gap, the water-absorbent resin efficiently absorbs and inflates the high-pressure groundwater that has invaded through the gap, and adheres to the concrete segment and the injection hole pipe, respectively. In particular, it is preferable to prevent water from passing through the concrete segment and prevent water from entering the concrete segment.

Further, as described above, when making the concrete segment, the water-swellable seal packing of the present invention is used by being attached to an injection hole pipe in advance, and the hydraulic expansion seal is buried in the state where the injection hole pipe is buried. It is also suitable for use in making concrete segments with cement materials. What if, when the water-absorbent resin absorbs the moisture contained in the hydraulic cement material, the gap between the concrete segment and the injection hole pipe is sufficiently closed from the time of molding the concrete segment, and used as a concrete pipe This is because an excellent waterproof effect can be obtained from the beginning.

Next, the form of the water-swellable seal packing of the present invention will be described. That is, the form of the water-swellable seal packing can be freely deformed or processed according to the application, and is not particularly limited,
As shown in FIG. 2, it is preferable to process the cylindrical shape in advance. For example, when used in the gap between a concrete segment and an injection hole pipe, attachment to the injection hole pipe becomes possible easily and quickly, and furthermore, the surrounding area is uniformly surrounded, and an excellent waterproof effect is provided. To get

Further, when the water-swellable seal packing of the present invention is used for the purpose, depending on the outer diameter of the injection hole pipe,
It is preferable to determine the inner diameter of the cylindrical water-swellable seal packing, and specifically, in consideration of the mounting properties and the waterproof effect of the water-swellable seal packing, the outer diameter of the injection hole pipe is taken into consideration. A tubular water-swellable seal packing having an inner diameter of 3 to 8 mm smaller is preferable. Therefore, using a hand or a jig, the cylindrical water-swellable seal packing is weakly widened,
It will be pressed into the injection hole pipe.

Further, the length of the cylindrical water-swellable seal packing also depends on the application.
The range of m is preferred. If it is less than 10 mm, the waterproof effect may be poor. On the other hand, if it is more than 30 mm, an excellent waterproof effect may be obtained, but there is a possibility that the mountability to an adherend and the moldability may be reduced.

However, in the present invention, the form is cylindrical.
It is not necessary for the water-swellable seal packing to be physically connected around the entire circumference, and it is sufficient that the seal can be installed along the circumference of the injection hole pipe in a cylindrical form.

Therefore, if the water-swellable seal packing is prepared as a plate-shaped divided piece, and a joint portion that can be fitted is provided at both ends of the divided piece, the pipe can be formed into an injection hole pipe having an arbitrary outer diameter. It is suitable in the present invention because it can be adapted as a shape and the construction is very easy.

It is also preferable that the water-swellable seal packing is processed into the above-mentioned cylindrical shape, and a part of the water-swellable seal packing is cut and opened. Not only is it easy to create, it can be adapted as a cylindrical form to an injection hole pipe of any outer diameter, and the construction is also extremely easy, and further, in the cut portion, the water absorbent resin is easily This is because there is no risk of expansion and a decrease in the waterproof effect.

In addition, at least one side of the plate-shaped split piece constituting the water-swellable seal packing is provided with a rubber /
It is also preferable to provide an adhesive layer made of a phenolic resin-based adhesive or an epoxy adhesive, for example, in addition to facilitating the work and improving the adhesion between the injection hole pipe and the water-swellable seal packing. It is.

In another preferred embodiment of the present invention,
As shown in FIGS. 5 to 7, the surface of the water-swellable seal packing has an uneven shape. If a water-swellable seal packing is used, for example, in the gap between a concrete segment and an injection hole pipe, the entry path for groundwater is mainly that of the surface of the water-swellable seal packing on the concrete segment side. This is because the longer the creepage distance of the surface, the slower the infiltration speed of the groundwater, and as a result, the easier the water-swellable seal packing absorbs water. In addition, by providing the uneven shape on at least one surface, the width of the cylindrical water-swellable seal packing can be easily widened, and for example, there is an advantage that attachment to an injection hole pipe becomes easy.

Here, the concave and convex shape may be a mountain-and-valley shape as shown in FIG. 5, or a semi-cylindrical shape as shown in FIG. 6, and a rectangular shape as shown in FIG. May be used. The size of the uneven shape is not particularly limited. For example, a shape having a height of 1 to 2 mm and a pitch of 1 to 2 mm is preferable from the viewpoint of excellent waterproofing effect and easy production. .

In another preferred embodiment of the present invention,
It is a water-swellable seal packing in the form of a tape having a thickness of 2 to 4 mm. If it is a tape shape, depending on the outer diameter and purpose of the adherend, it is possible to wrap the adherend twice or three times, and furthermore, for example, the length of the injection hole pipe as the adherend In the direction, it is also possible to spirally wind, depending on the estimated groundwater pressure, etc., anticipate the waterproof effect,
It is suitable for the present invention in that it can be varied.

When a tape-shaped water-swellable seal packing is used, it is preferable that the rubber-based cross-linking agent is crosslinked after the tape-shaped water-swellable seal packing is wound around the adherend. It is. Before the crosslinking of the water-swellable seal packing, that is, in the case of a green sheet state, the fluidity of the rubber is good, because it is sufficient and easy to wind, and in the case of the green sheet state, it is superposed. This is because the rubbers are easily fused to each other, and a higher waterproof effect can be expected.

In another preferred embodiment of the present invention,
It is processed into granules having an average particle size of 1 to 50,000 μm, more preferably, an average particle size of 10 to 5,000 μm. It is also preferable to knead and fill.

(Embodiment of the Invention) The present invention will be described in more detail based on examples.

(Example 1) Mixing of rubber composition The mixture was kneaded using three rolls to prepare a rubber composition of No. 1 shown in Table 1. However, it is also preferable to use a kneading machine such as a Banbury mixer or an intermix, depending on the use of the water-swellable seal packing and the difference in raw materials used.

2. Molding of Water-Expandable Seal Packing The rubber composition kneaded and compounded using three rolls was heated at a temperature of 1
Using a mold at 50 ° C., a cylindrical water-swellable seal packing having the following specifications was molded and further subjected to the following test. Inner diameter: 64mm Outer diameter: 75mm Length: 10mm Height of outer surface irregularities: 1.0mm Pitch of outer surface irregularities: 1.5mm

(1) Measurement of Weight Expansion Coefficient 1 According to JIS K7209, 21
The sample was immersed for days, and the weight expansion rate (%, water absorption) was calculated from the weight change during that time.

(2) Measurement of weight expansion coefficient 2 According to JIS K7209, the sample was immersed in tap water at 70 ° C. for 7 days, and the weight expansion rate (%, water absorption rate) was calculated from the weight change during that time. did.

(3) Measurement of form retention 1 The appearance of the sample used in the measurement 1 of the coefficient of weight expansion was visually judged based on the following criteria. 〇: No remarkable change △: Deformation is observed in part of the sample ×: Deformation is observed in the entire sample

(4) Measurement of form retention 2 The appearance of the sample used in the measurement 2 of the coefficient of weight expansion was visually judged based on the following criteria. 〇: No remarkable change △: Deformation is observed in part of the sample ×: Deformation is observed in the entire sample

(5) Measurement of tensile strength Tensile strength was measured using a tensile tester manufactured by Toyo Seiki Co., Ltd. in accordance with JIS K6301.

(6) Measurement of Elongation at Break In accordance with JIS K6301, a tensile tester manufactured by Toyo Seiki Co., Ltd. was used to measure elongation until the sample broke.

(7) Waterproofing Effect Test Steel outer diameter 70 mm, inner diameter 58 mm, length 200
The above-mentioned cylindrical water-swellable seal packing was attached to a substantially end portion of an injection hole pipe having a diameter of mm. Then, after standing almost at the center of a substantially flat mold for molding a concrete segment, a hydraulic cement material was poured into the mold. And curing and hardening the hydraulic cement material,
The mold was removed to obtain a concrete segment to which the water-swellable seal packing was attached. And further, using a compressor, pressurized water of 6 kgf / cm ² ,
It was applied to the gap between the injection hole pipe and the concrete segment. The result was judged based on the following criteria. 〇: No significant water intrusion into the concrete segment △: Slight water intrusion into the concrete segment ×: Remarkable water intrusion into the concrete segment

(Examples 2 to 6) The same test as in Example 1 was repeated using the rubber compositions of Formulations 2 to 6 shown in Table 1 instead of the rubber composition of Formulation 1 of Example 1. .
Table 1 shows the results.

(Comparative Examples 1 and 2) Formulation No. 1 of Example 1
The same test as in Example 1 was repeated using the water-absorbent resin and the rubber composition of Formulation Nos. 7 and 8 shown in Table 1 instead of the rubber composition of Table 1. Table 1 shows the results.

[0073]

[Table 1]

[0074]

According to the present invention, the water-swellable seal packing absorbs moisture to obtain an excellent waterproofing effect, and the water-swellable seal packing has excellent shape retention after water absorption (creep resistance). ), And an excellent waterproof effect was obtained in the long term.

Specifically, a tubular water-swellable seal packing was mounted around an injection hole pipe buried in a concrete segment used for making a tunnel or the like, and the injection hole pipe was buried. As a result of hardening the hydraulic cement material in this state to produce the concrete segment, a concrete segment having an excellent waterproof effect was easily obtained.

[Brief description of the drawings]

FIG. 1 is a diagram in which a cylindrical water-swellable seal packing of the present invention is mounted on an injection hole pipe.

FIG. 2 is a view showing an appearance of a cylindrical water-swellable seal packing of the present invention.

FIG. 3 is a diagram showing a concrete pipe constructed using the water-swellable seal packing of the present invention.

FIG. 4 is a view showing a concrete segment into which an injection hole pipe equipped with a tubular water-expandable seal packing of the present invention is inserted.

FIG. 5 is a cross-sectional view of a water-swellable seal packing having a suitable uneven surface according to the present invention.

FIG. 6 is a sectional view of a water-swellable seal packing having another preferable uneven surface according to the present invention.

FIG. 7 is a cross-sectional view of a water-swellable seal packing having yet another preferable uneven surface according to the present invention.

[Explanation of symbols]

 1: Water-swellable seal packing 2: Injection pipe 3: Concrete segment

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kotaro Sato 2-22-22 Kanda Sakuma-cho, Chiyoda-ku, Tokyo Within Nikka Industries Co., Ltd. (72) Inventor Shoji Uwano 2-5-2-24 Atago, Kazo City, Saitama

Claims (6)

[Claims] 1. A water-swellable seal packing made of a rubber composition containing a rubber and a water-absorbing resin is mounted around an injection hole pipe buried in a concrete segment, and the injection hole pipe is buried. A method for using a water-swellable seal packing, which is used when a hydraulic cement material is cured to form the concrete segment. 2. The rubber composition according to JIS K7209.
50% or more at a weight expansion coefficient (23 ° C.) according to JIS K6301 and a tensile strength according to JIS K6301
In breaking elongation conforming to 4~150Kgf / cm ^2, JIS K6301, using the water-swellable seal packing according to claim 1, characterized in that less than 200%. 3. The water-swellable seal packing according to claim 1, wherein the rubber composition contains 10 to 40 parts by weight of the water-absorbing resin based on 100 parts by weight of rubbers. how to use. 4. The rubber composition as a water crosslinking component,
The method of using a water-swellable seal packing according to any one of claims 1 to 3, further comprising a ketiminated polyamide resin and a glycidyl ether compound. 5. The method of using a water-swellable seal packing according to claim 1, wherein the water-swellable seal packing has an uneven shape on at least one surface. 6. The form of the water-swellable seal packing is as follows:
2. A cylindrical or tape-like shape.
A method for using the water-swellable seal packing according to any one of Items 1 to 5.