Patent Application
20080187704
The present invention relates to a water-sealing material to be fitted to the outer circumferential surface of a pipe, such as a pipe penetrating the outer wall of a structure and the like. In particular, the present invention relates to a pipe-surrounding water-sealing material that can reduce damages caused by construction defects, and remarkably reduce construction labor.
Heretofore, water-sealing materials used in the construction and civil engineering fields have been used for portions in which water leakage occurs, such as a concrete construction-joint part, a contact surface between concrete and other members, and a junction surface between concrete secondary products. The following are known as materials for such water-sealing materials: (1) water-sealing plates that block a water leakage path with a rubber plate buried in a construction-joint part, the rubber plate which is obtained by forming a rubber into a plate, and rubber-based water-sealing materials that block a water leakage path by chemical bonding of a rubber buried in a construction-joint part and concrete due to a concrete curing reaction and an ionic reaction; (2) organic material-based water-swelling water-sealing materials having water swelling functions, which are obtained by mixing a water-swelling polymer with a resin and/or rubber, the organic material-based water-swelling water-sealing materials exhibiting water-sealing effects by utilizing contact surface stress due to the expansion pressure attributable to the swelling functions; and (3) water-sealing panels or water-sealing ropes, in which powder or granular water-swelling clay, such as bentonite or smectite, is filled or held in a corrugated paper, nonwoven fabric, or the like, and inorganic-based water-swelling water-sealing materials which are obtained by kneading water-swelling clay and an adhesive composition in which a gel-formation base oil, asphalt, or the like, is utilized, to form into a shape.
Among the above-mentioned water-sealing materials, with respect to the above-mentioned (1), the water-sealing materials themselves are not water-permeable, but they cannot fill gaps generated upon concrete contraction at the timing of concrete curing, and they merely lengthen and complicate the water leakage path of the concrete construction-joint part. As a result, satisfactory water-sealing effects were not expected. The water-sealing materials mentioned in (1) are combined with concrete by a chemical reaction, and thus an effect of preventing water leakage from a gap generated upon concrete contraction can be expected. However, the water-sealing materials mentioned in (1) above pose problems that when the concrete deforms or moves due to contraction or external force, the resultant concrete is separated or peeled-off from the rubber, resulting in water leakage.
The water-sealing materials mentioned in (2) above absorb water and swell, which may expect to thereby produce an effect of filling a gap generated by concrete contraction. However, since the expansion pressure is high, the water-sealing materials mentioned in (2) pose problems of cracking and/or separation of concrete and/or breakage of a pipe, etc.
The water-sealing materials mentioned in (3) above are free from problems of cracking of concrete and breakage of a pipe, because no excessive swelling pressure is to be formed. However, the water-sealing materials that are referred to as water-sealing panels or water-sealing ropes suffer from dropping and/or uneven distribution of bentonite, and thus cannot stably exhibit water-sealing effects over a long period of time. In addition, due to their high swelling speeds, the water-sealing materials mentioned in (3) completely swell when floods by rainfalls, ground waters, etc. occur before placing the concrete in a prescribed portion, and thus water-sealing effects conspicuously are reduced.
Further, since the materials mentioned in (1) and (2) above are composed of organic materials, the water-sealing effects of the materials were lowered with the lapse of time. That lowering is caused, for example, by deterioration of the materials due to the environment where the materials are to be placed, decomposition of the materials by bacteria in the soil, and the like. Thus, the initial water-sealing effects cannot be maintained over a long period of time due to the nature of the materials themselves, which is a problem.
In the mean time, the following are heretofore known as methods for fitting a pipe-surrounding water-sealing material to the outer circumferential surface of a pipe, such as a pipe penetrating the outer wall of a structure and the like, to thereby construct the pipe-surrounding water-sealing material to a given portion: (4) methods for welding a collar composed of a metal or resin to the surrounding of a pipe, to thereby fit the collar to the pipe's surrounding; (5) methods for sticking around a pipe a water-sealing material having plasticity, by utilizing self-adhesion force, an adhesive, a double-sided tape, etc.; and (6) methods for fitting an annular fixed-form elastic material composed of rubber and the like around a pipe, to thereby clamp and fix the pipe with the annular material by elasticity of the rubber material. Among these methods, the methods mentioned in (4) above achieve extremely high resistance to external force, because a collar is fitted to a pipe by welding. However, tremendous labor and advanced skills are required for the process of the welding operation. In addition, the collar merely lengthens and complicates a water path of a boundary surface between a pipe and concrete, and the resultant water-sealing effects are not satisfactory. The methods mentioned in (5) above use materials having water-swelling functions in many cases, and thus higher water-sealing effects can be expected as compared with the methods mentioned in (4) above. However, the methods mentioned in (5) above pose problems of separation and/or dropping of the water-sealing materials due to poor adhesive strength or poor adhesion, and/or prior swelling or contraction deformation of the water-sealing materials, and/or external force caused by placing concrete.
On the other hand, the methods mentioned in (6) above are free from the problems of separation and dropping of the water-sealing materials composed of rubber. However, in the methods, a sleeve pipe is clamped for fixation, and thus elasticity becomes strong. Therefore, a considerably strong force is needed for construction because the clamping force changes into repulsive force at the timing of construction. In addition, due to the clamping force, a problem arises that a strong force is required for moving a construction site.
Currently, almost of the products used as pipe-surrounding water-sealing materials have rectangular cross sections, and some of such products are partially uneven. These shapes are determined considering water-sealing effects, but not considering workability and/or resistance against external force caused by placing concrete, etc. Thus, there is a problem that when pipe-surrounding water-sealing materials are fitted to a pipe by a primer, self-adhesion, etc., the pipe-surrounding water-sealing materials are separated (or peeled off) from an intended portion and/or shifted (or moved) to a portion not intended to apply the material due to external force, when poor adhesion or the like occurs. In addition, since a pipe-surrounding water-sealing material that has an annular shape and that is fixed to a pipe by clamping force of the material, the clamping force is considerably strong to counteract against external force, and thus the pipe-surrounding water-sealing material has such problems that a considerably strong force is required upon construction and workability is poor.
The present invention resides in a pipe-surrounding water-sealing material, which is composed of an elastic composition, and which has an annular shape. Herein, the “pipe-surrounding water-sealing material” means a material of sealing water around a pipe. The “elastic composition” means a composition that is expansive and contractive.
Other and further features and advantages of the invention will appear more fully from the following description, appropriately referring to the accompanying drawings.
According to the present invention, there is provided the following means:
(1) A pipe-surrounding water-sealing material, which is composed of an elastic composition, and which has an annular shape;
(2) The pipe-surrounding water-sealing material according to item (1), wherein the elastic composition has a water swelling property;
(3) The pipe-surrounding water-sealing material according to item (2), wherein the elastic composition having a water-swelling property contains a water-swelling clay mineral;
(4) The pipe-surrounding water-sealing material according to any one of items (1) to (3), wherein a cross section perpendicular to a target pipe has a substantially semicircular or semi-elliptic shape having a base side in contact with the pipe;
(5) The pipe-surrounding water-sealing material according to item (4), wherein an edge in the circumferential direction of the pipe-surrounding water-sealing material is beveled (or chamfered); and
(6) The pipe-surrounding water-sealing material according to any one of items (1) to (3), wherein a cross section perpendicular to a target pipe has a polygonal shape having a base side in contact with the pipe, and wherein an angle formed between the target pipe and a tangent of an upper shape of the polygonal shape is an obtuse angle.
Herein, the term “being composed of” means to include not only the case where the pipe-surrounding water-sealing material is made only of the elastic composition but also the case where the pipe-surrounding water-sealing material is made of the elastic composition and another optional component(s).
The pipe-surrounding water-sealing of the present invention is composed of an elastic composition, and has an annular shape. For the elastic composition used in the present invention, there is no need to use any organic material, such as rubber, which itself has elasticity. As the composition, a water-swelling composition is more preferable. As the water-swelling composition, a composition containing a water-swelling clay is preferable. The elastic composition that is preferably used in the present invention is a composition with high expansive-and-contractive property (flexibility), according to JIS K 6301, whose tensile strength is preferably 0.1 MPa or higher, and more preferably 0.15 MPa or higher, and whose elongation is preferably 200% or more, and more preferably 300% or more. Further, according to the aforementioned JIS K 6301, the compression permanent set of the elastic composition is preferably 65% or lower, and more preferably 50% or lower, and the impact resilience thereof is preferably 10% or more, and more preferably 20% or more.
Examples of the water-swelling composition that can be preferably used in the present invention include a water-swelling composition that is composed of 5 to 90 mass parts (preferably 5 to 80 mass parts) of a water-swelling clay mineral, 5 to 30 mass parts (preferably 5 to 20 mass parts) of an asphalt, 3 to 30 mass parts (preferably 5 to 25 mass parts) of an elasticity-imparting agent, and 5 to 40 mass parts (preferably 10 to 35 mass parts) of a plasticizer.
As the water-swelling clay mineral that can be used in the above-mentioned water-swelling composition, any of native or denatured water-swelling clay minerals may be used. Preferable is at least one selected from smectite-based clay minerals, such as bentonite, hectorite, etc., and swelling mica. Among these, bentonite is a particularly preferable clay mineral for the following reasons: bentonite is excellent in safety, because it is a naturally-produced inorganic clay mineral; bentonite is stable and a high water-sealing effect can be maintained over a long period of time, because bentonite is not decomposed by microorganisms in the soil; and bentonite is available at an inexpensive cost.
As the asphalt that can be used in the above-mentioned water-swelling composition, use may be made of any of natural asphalts, such as lake asphalt, asphaltite, rock asphalt, etc., or petroleum asphalts, such as straight asphalt, blown asphalt, etc. Further, any of modified asphalts, such as an asphalt compound, a rubberized asphalt, etc., can also be used.
Generally preferable as the elasticity-imparting agent that can be used in the above-mentioned water-swelling composition is one that can be used as an asphalt modifier, although not limited thereto. Examples of the elasticity-imparting agent include thermoplastic elastomers, such as styrene/butadiene block (SBS) copolymers, styrene/isoprene block copolymers, styrene/ethylene/butadiene block copolymers, etc. Further, preferable as the plasticizer that can be used in the above-mentioned water-swelling composition is an oil which can be obtained by refining petroleum and which is generally referred to as a process oil.
The above-mentioned water-swelling composition can include, as an optional component(s) in addition to the above-mentioned components, any of various additives that are conventionally used for water-sealing materials, if necessary, insofar as the excellent effects exhibited by the present invention are not adversely affected. Examples of the additive include softeners (e.g., oils, such as synthetic oils, fatty oils, etc.), stabilizers (e.g., anionic surfactants, nonionic surfactants, etc.), antifoaming agents, antifreezing agents, antioxidants, fillers, colorants, etc.
There is no limitation on the order and method for adding and mixing the components, in producing the above-mentioned water-swelling composition. The above-mentioned water-swelling composition can be obtained as a uniform mixture, by sufficiently mixing a water-swelling clay mineral, an asphalt, an elasticity-imparting agent, and a plasticizer. During this process, the mixing can be facilitated by heating. Generally, the mixing is sufficiently performed under heating at a temperature of 70 to 250° C., and preferably 100 to 200° C., preferably until a uniform mixture is given. During this process, a prolonged heating at a high temperature may lower the quality of the above-mentioned water-swelling composition, and thus heating is preferably performed within the above-mentioned temperature range.
The pipe-surrounding water-sealing material of the present invention, which utilizes an elastic composition and has an annular shape, has preferably in the following shape: that a cross section perpendicular to a target pipe to which the pipe-surrounding water-sealing material is applied, has a substantially semicircular shape or semi-elliptic shape in which a base side is in contact with the pipe, or has a polygonal shape in which a base side is in contact with the pipe, and that an angle that is formed between the tangent of the aforementioned shape (i.e. the substantially semicircular shape, the substantially semi-elliptic shape, or the polygonal shape) and the pipe is an obtuse angle. Further, the pipe-surrounding water-sealing material having a curved upper portion can be easily moved, by rotation of the pipe-surrounding water-sealing material to a construction site of the pipe, by beveling or chamfering an edge portion in the circumferential direction of the curved pipe-surrounding water-sealing material in advance.
The water-sealing material 1 of this embodiment is constructed in such a manner that the upper surface of the pipe-surrounding water-sealing material 1 would have a curved shape, and a flat portion 2 would touch or be in contact with the pipe upon the construction, as shown in
Further, the water-sealing material of the present invention can be more easily moved by rotation, by beveling the edge in the circumferential direction to form a chamfered part 4, as shown in
The curved portion 3 is in contact with concrete to be placed, and the concrete cures along the curved portion, with the result that sufficient water-sealing effects can be exhibited. The curved portion may be complicated by providing a projection(s) or the like on the surface thereof. However, when concrete fails to follow the projection(s) well, a water leakage path may be formed in the projection portion(s), to thereby cause a danger of increasing the possibility of water leakage. Thus, it is preferable to avoid a specific shape of the surface of the curved portion in which concrete fails to follow the shape.
The shape of the upper portion is not particularly limited to a curved shape, and a cross section may have a polygonal shape.
The pipe-surrounding water-sealing material of present invention has excellent durability according to the life time of buildings and/or structures, exhibits a high water-impermeable property (waterproof property), prevents peeling off and/or shifting/dropping of the water-sealing material from the pipe due to external force, and is excellent in workabilities, such as fitting to and detaching from the pipe, moving of the water-sealing material to a construction site for the pipe, etc.
Since the pipe-surrounding water-sealing material of the present invention, basically, can be composed mainly of an inorganic substance(s), degradation thereof with the lapse of time is difficult to occur. Thus, the water-sealing performance of the pipe-surrounding water-sealing material is not lowered with the lapse of time, and thus a desired water-sealing effect can be maintained over a long period of time when it is used for buildings or structures. Further, the pipe-surrounding water-sealing material of the present invention is good in workability, and can be easily moved to a construction site. Moreover, a pipe-surrounding water-sealing material having a higher resistance against external force caused by placing concrete or the like, can be obtained. As a result, it is possible to obtain a pipe-surrounding water-sealing material free from peeling off/dropping, while preventing construction defects, such as poor adhesion and an insufficient adhesive strength. In addition, the water-sealing material can be easily moved to a construction site by, for example, inserting the water-sealing material in the upper portion of a pipe, by utilizing the expansive-and-contractive property thereof and rotating the resultant in such a manner that the front and rear surfaces are successively switched, which makes it possible to remarkably improve the workability.
Hereinafter, the present invention will be described in more detail based on the following examples, but the invention is not intended to be limited thereto. Rather, various aspects or embodiments that can be conceived from the above descriptions and the following disclosures should be encompassed in the scope of claims of the present invention.
Using a kneader equipped with a heating jacket, 55 mass parts of a bentonite (manufactured by Kunimine Industries Co., Ltd.; trade name, Kunigel VA), 5 mass parts of a straight-asphalt of penetration number 60/80, 10 mass parts of an SBS copolymer, and 30 mass parts of a process oil were sufficiently mixed under heating at 170° C., to thereby prepare a water-swelling composition. A given amount of the thus-obtained water-swelling composition was poured, in a molten state under heating, into a mold in such a manner that the cross section would be formed into an equilateral triangle, to thereby shape the water-swelling composition. The end portions of the thus-obtained samples were adhered with each other, to give Sample 1 of an annular shape. Separately, a non-annular (rectangular strip-shaped) sample as it was taken out from the mold is designated to as Sample 2, as a reference example.
A given amount of the water-swelling composition as used in Example 1 was poured, in a molten state under heating, into a mold in such a manner that the cross section would be formed into a semicircular shape, to thereby shape the water-swelling composition. The end portions of the thus-obtained samples were adhered with each other, to give Sample 3 of an annular shape. Separately, a non-annular (rectangular strip-shaped) sample as it was taken out from the mold is designated to as Sample 4, as a reference example.
A given amount of the water-swelling composition as used in Example 1 was poured, in a molten state under heating, into a mold in such a manner that the cross section would be formed into a trapezoid shape, to thereby shape the water-swelling composition. The end portions of the thus-obtained samples were adhered with each other, to give Sample 5 of an annular shape. Separately, a non-annular (rectangular strip-shaped) sample as it was taken out from the mold is designated to as Sample 6, as a reference example.
A given amount of the water-swelling composition as used in Example 1 was poured, in a molten state under heating, into a mold in such a manner that the cross section would be formed into a rectangular shape, to thereby shape the water-swelling composition. The end portions of the thus-obtained samples were adhered with each other, to give Sample 7 of an annular shape. Separately, a non-annular (rectangular strip-shaped) sample as it was taken out from the mold is designated to as Sample 8, as a reference example.
The thus-obtained samples were validated for the resistance against external force, according to the following method. The cross-section size was fixed to a base plane in contact with a sleeve pipe to be 14 mm in width and the height from the base plane to the top end to be 10 mm. The inner diameters of the annular samples were made uniform, and the lengths of the non-annular samples taken out from the molds were made uniform.
A test piece to be used for a validation test for resistance against external force is explained with reference to
As is apparent from the results shown in Table 1, with respect to the samples according to the present invention, no phenomenon of peeling-off/shifting/twisting was observed, at 100 g per second. Further, even if the external force was increased as high as 500 g per second, the Samples 1, 3, and 5 decreased the external force, and thus no phenomenon of peeling-off/shifting/twisting was observed. However, since the Sample 7 did not decrease the external force, phenomena of shifting/twisting were observed. Further, the Sample 8 was peeled off and dropped off at 500 g per second. Furthermore, although not shown in Table 1, in the case of insufficient bonding in the Samples 2, 4, and 6, no phenomenon of peeling-off/shifting/twisting was observed, at 100 g per second, but these samples were peeled off and dropped off, at 500 g per second.
Having described our invention as related to the present embodiments, it is our intention that the invention not be limited by any of the details of the description, unless otherwise specified, but rather be construed broadly within its spirit and scope as set out in the accompanying claims.
This non-provisional application claims priority under 35 U.S.C. §119 (a) on Patent Application No. 2007-023706 filed in Japan on Feb. 2, 2007, which is entirely herein incorporated by reference.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2007-023706 | Feb 2007 | JP | national |
