JP2003118023A - Self-repairable waterproof sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waterproof sheet which prevents the entrance of water into the body of the sheet even when the sheet is cracked. SOLUTION: Rainwater, groundwater, etc. are prevented from reaching a water absorbing swelling layer 4 by a cover body 5 even when the sheet base material 2 surface of the waterproof sheet 1 in which a fiber aggregate 3 is fixed to the back of the waterproofing, flexible sheet base material 2, the swelling layer 4 is formed on the back of the fiber aggregate 3, and the cover body 5 soluble in alkali water adherent to the surface of cement kept at room temperature is formed on the back of the swelling layer 4 is fixed to a provisional form L or a form K before the placement of concrete. After the placement of the concrete, the cover body 5 of the waterproof sheet 1 is dissolved by the concrete, and the swelling layer 4 is adhered to the outer wall surface W of the building frame. Even when the sheet base material 2 is cracked, and water enters from the crack, the water is absorbed by a clay mineral which is swelled and gelatinized to be prevented from reaching the building frame.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-healing waterproofing sheet having a high water-blocking property utilizing swelling properties of clay minerals and the like. 2. Description of the Related Art Conventionally, there are various waterproofing methods for waterproofing a wall surface and a floor surface of a flat roof, an underground structure, and the like. However, the waterproofing method can be performed at room temperature, and the waterproof layer is uniform, uniform, and lightweight. In synthetic polymer roofing (hereinafter referred to as sheet waterproofing), a woven or nonwoven fabric made of synthetic fiber, carbon fiber or glass fiber is reinforced with a vinyl chloride resin, vulcanized rubber or non-vulcanized rubber sheet base material. A waterproof sheet material formed by laminating is seen. In the waterproofing method using a waterproof sheet, the concrete is attached to the skeleton concrete by a fixing means such as an adhesive or a nail to absorb fluctuations such as cracks in the skeleton. However, in the case of sheet waterproofing using the above waterproof sheet, the joints of the waterproof sheet may be peeled off or the waterproof sheet base material may crack due to fluctuations due to drying of the skeleton concrete, heat of hydration reaction, earthquakes, and the like. If the waterproofing effect is impaired by this, it is necessary to repair the poor waterproofing part (peeled part or cracked part) of this waterproofing sheet, remove the pressing layer on the surface of the waterproofing sheet and reconstruct it, and it requires a great deal of cost. In an underground structure constructed on a small site, it is extremely difficult to repair the waterproof sheet attached to the outer wall surface because the soil outside the wall surface cannot be sufficiently excavated. [0003] Therefore, between two sheets of synthetic fiber nonwoven fabric or cardboard, a sheet-like or plate-like water-stopping material in which clay minerals such as bentonite and bentonite containing modified asphalt which swell and gel by water absorption are fixed and held. Wood can be seen. In addition, in addition to the waterproof sheet, the clay mineral rod-shaped,
Water-stopping materials are also found in concrete joints that are formed into strips or tapes or that the surface of this clay mineral is coated with a water-soluble film or release paper. [0004] However, when the above-mentioned water-blocking material utilizing the clay mineral is installed on the outer wall surface of the underground structure, for example, a temporary formwork or a formwork (hereinafter referred to as a formwork) is required. After fixing the waterproofing material inside of) and adopting the method of placing concrete on the outer wall of the skeleton by installing concrete, between the time when the waterproof material is attached to the formwork and the time when concrete is poured, It is more likely that the waterstop material will be wet by rainfall or groundwater, in which case the water will penetrate into the nonwoven fabric or cardboard itself, forming a waterway, and the clay minerals flowing away from the nonwoven fabric or cardboard, causing a significant loss of water stopping effect. Therefore, not only is it necessary to take measures such as covering the waterproof material, but also in places where there is a large amount of groundwater, there is a risk that clay minerals may flow out of the waterproof material due to flooding of the underground structure. According to the present invention, when a waterproofing material based on the above-mentioned prior art is used on the outer wall surface of an underground structure using a clay mineral, a waterproof material fixed to a formwork is used. In view of the problem that needs to be cured, a fiber aggregate is fixed to the back surface of a waterproof and flexible sheet base material, and the back surface of the fiber aggregate has, for example, a water-absorbing swelling composed of a swellable clay mineral. By forming a layer and providing a waterproof sheet provided with an alkali-soluble coating on the back surface of the water-absorbing swelling layer on the concrete body, even if the waterproof sheet base material cracks, the water entering therefrom is covered with a clay mineral. It absorbs and swells to gel to prevent it from reaching the skeleton. Also, if the sheet substrate side of the waterproof sheet is fixed to the formwork before concrete is poured, the covering is exposed, so that rainwater, groundwater, etc. does not reach the water-absorbing swelling layer, and the concrete is covered after the concrete is placed. The object is solved by dissolving the body and bringing the water-absorbing swelling layer into close contact with the outer wall surface of the skeleton. An embodiment of the present invention will be described below with reference to the drawings. The self-healing waterproof sheet 1 (hereinafter referred to as a waterproof sheet 1) is a waterproof sheet used for waterproofing a flat roof surface of a building and an outer wall surface W of an underground structure.
The sheet 1 comprises a thin sheet substrate 2 and the sheet substrate 2
A fiber assembly 3 such as a nonwoven fabric having a low fiber density formed so as to be fluffed on the back surface is fixed, and the water-absorbing swelling layer 4 is formed on the back surface of the fiber assembly 3 to a predetermined thickness so as to be adapted to the fiber assembly 3. Is fixed, and a cover 5 is provided on the back surface. The sheet base material 2 of the waterproof sheet 1 is made of vinyl chloride synthetic resin, vulcanized rubber-based or non-vulcanized rubber-based material, etc., and thus has waterproofness and flexibility.
Any material having high strength that is not easily broken may be used, and a material having a smooth surface is particularly desirable. In the fiber assembly 3 of the waterproof sheet 1, the constituent fibers of the back surface of the sheet material 4, such as a woven or nonwoven fabric made of a woven or nonwoven fabric made of synthetic fiber, carbon fiber or glass fiber, are fluffy. State, or a state in which the constituent fibers are intertwined, or may be a state in which the fibers are simply fixed to the back surface of the sheet substrate 2 so as to scatter innumerable curled fibers. It is desirable that the water absorption swelling layer 4 be large to some extent so as to penetrate sufficiently. The water-absorbing swelling layer 4 is made of, for example, bentonite, sepiolite, or bentonite containing modified asphalt, and has a swelling property. A semi-kneaded state is obtained by adding a maintenance agent and a viscosity modifier.
The viscosity maintaining agent is for maintaining the viscosity of the kneaded product of bentonite and sepiolite, and is an alcohol such as glycol, or an oil such as castor oil or kerosene. It is for adjusting. In addition, the coating 5 is made of, for example, a film of a polylactic acid resin or the like, which is insoluble in water, that is, a film formed of a substance soluble in alkaline water attached to the surface of the cement at room temperature. good. 3 and 5 are cross-sectional views of the outer wall before the coating 5 is melted. If left as it is, the coating 5 is melted and disappears. Next, a method of applying the self-healing waterproof sheet 1 according to the present invention will be described. Since the waterproofing sheet 1 effectively exhibits a waterproof effect particularly when it is applied to the outer wall surface W of an underground structure, a method of applying the waterproofing sheet 1 will be described in detail below. In the construction of the waterproof sheet 1, a method of fixing the waterproof sheet 1 to the formwork K or the temporary formwork L before casting concrete (waterproofing method outside the head) is preferable. As shown in FIG. 2, the first construction method is a construction method in which the waterproof sheet 1 is temporarily fixed to a formwork K to be removed after placing concrete. In this method, as shown in FIG. 2A, a formwork K is assembled on the ground side of an underground structure, and a waterproof sheet 1 is placed inside the formwork K.
After the sheet substrate 2 is fixed so as to be in close contact with the mold K, the mold K is separately assembled with a predetermined space provided between the sheet K and the mold K. Then, as shown in FIG. 2 (b), concrete is poured between one formwork K and the other formwork K, and after curing and hardening of the concrete, each formwork K is removed. ), The soil P is backfilled in the space between the ground and the waterproof sheet 1. As shown in FIG. 4, the second construction method is a construction method in which the waterproof sheet 1 is installed on a driving (embedding) type temporary formwork L. In this method, as shown in FIG. 4 (a), a temporary form L is assembled on the ground side of an underground structure, and a waterproof sheet 1 is fixed inside the temporary form L so that the sheet base 2 is in close contact therewith.
The mold K is assembled at a predetermined interval from the temporary mold L. Then, as shown in FIG. 4B, the temporary form L, the form K
Concrete is poured in between, and after curing and hardening of the concrete, the formwork K is removed. Next, the operation of the self-healing waterproof sheet according to the present invention will be described. Since the concrete is alkaline, the cover 5 of the waterproof sheet 1 in contact with the concrete skeleton C is melted, and the surface of the water-absorbing swelling layer 4 appears on the concrete skeleton C side and comes into contact with the concrete skeleton C, thereby absorbing water. The swelling layer 4 absorbs the moisture of the concrete and swells and gels, and the flexibility of the water-absorbing and swelling layer 4 deforms corresponding to the concrete skeleton C, so that the water-absorbing and swelling layer 4 is completely adhered to the concrete skeleton C. Even if the waterproof sheet 1 breaks or peels off at the seam of the waterproof sheet 1, even if rainwater or groundwater intrudes from this, it absorbs water in the water-absorbing swelling layer 4 and
Does not reach the concrete skeleton C due to swelling gelation and water stoppage. Also, even if cracks occur in the concrete skeleton C,
The constituent material of the water-absorbing swelling layer 4, that is, the swollen clay mineral, penetrates into the site and is closed. At the time of backfilling the soil P, the sheet base material 2 of the waterproof sheet 1 has a high strength and does not break. If the surface is smooth, the resistance to the input soil P is small, and the state of adhesion of the waterproof sheet 1 to the frame is low. Will be maintained. According to the present invention, the fiber assembly 3 is fixed on the back surface of the waterproof and flexible sheet substrate 2 and the water-absorbing swelling layer 4 is formed on the back surface of the fiber assembly 3. Then, since the alkali-soluble coating 5 was provided on the back surface of the water-absorbing swelling layer 4, the sheet base material 2 was attached to the temporary form L or the form K on the ground side, and the coating 5 was placed on the concrete side to be post-constructed. By arranging, the coating body 5 can absorb the swelling layer 4 against rainwater and groundwater.
Therefore, it is possible to save time for curing the waterproof sheet 1, and after the concrete is poured, the covering 5 is melted because the concrete is alkaline, and the water-absorbing swelling layer 4 can be brought into close contact with the concrete. it can. In addition, a crack occurs in the sheet base material 2 applied to the skeleton for some reason,
Even if rainwater or groundwater tries to invade the skeleton side from this crack, the infiltrated water comes into contact with the water-absorbing and swelling layer 4 of the waterproof sheet 1, so that the water-absorbing and swelling layer 4 absorbs the infiltrating water and swells and gels. Intrusion into the building body can be prevented. Furthermore,
If there is a crack not only in the sheet base 2 but also in the frame,
By allowing the clay mineral gradually swelled and gelled from the cracked portion of the sheet base material 2 to permeate while flowing into the cracked portion of the skeleton together with the infiltration water, and adsorbing and filling the clay mineral into the cracked portion, the cracked portion becomes Since water can be stopped by being closed tightly by the swelled and gelled clay mineral, water leakage from cracked parts of the skeleton can be naturally stopped, and the above-mentioned waterproofing method makes it easy to fix to the concrete skeleton C. Even if one waterproof sheet 1 is torn, it does not require repair and can form a waterproof layer that does not impair the waterproofness. Since the water-absorbing swelling layer 4 is flexible and easily conforms to the body, the workability can be improved, and the water-absorbing swelling layer 4
Since the clay mineral itself has waterproofness, the waterproofing sheet 1 can exhibit a sufficient waterproofing function from the beginning of the construction of the waterproofing sheet 1 in combination with the waterproofing sheet base 2.
Can have immediate effect. In addition, waterproof sheet 1
When the waterproof sheet 1 is formed into a roll when transporting, the cover 5 is interposed between the waterproof sheet 1 and the back surface of the waterproof sheet 1 so that the water-absorbing swelling layer 4 does not adhere to the back surface of the waterproof sheet 1. Its practical effect is extremely large.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional perspective view of a waterproof sheet according to the present invention. FIG. 2A is a cross-sectional view showing a state in which a waterproof sheet is attached to a formwork arranged in an excavated space, and FIG.
It is sectional drawing which shows the state which poured concrete between the formwork, (c) is sectional drawing which shows the state which buried the outside of the waterproof sheet after formwork removal. FIG. 3 is an enlarged cross-sectional view showing a state in which the waterproof sheet according to the present invention is applied to an outer wall surface of an underground structure. FIG. 4A is a cross-sectional view showing a state where a waterproof sheet is attached to a temporary formwork arranged in an excavated space, and FIG.
FIG. 4 is a cross-sectional view showing a state where concrete is poured between the temporary formwork and the formwork. FIG. 5 is an enlarged cross-sectional view showing a state in which the waterproof sheet according to the present invention is applied to a temporary formwork of an outer wall of an underground structure. [Description of Signs] 2 Sheet base material 3 Fiber aggregate 4 Water-absorbing swelling layer 5 Coating

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) E04D 5/10 E04D 5/10 F // B32B 9/00 B32B 9/00 A F term (reference) 2D047 AA02 2E001 DA01 FA24 GA24 HD12 HD13 HE01 HE03 HF01 4F100 AR00A AR00C AR00D BA04 BA07 BA10A BA10D DG06B GB07 GB90 JB08D JB10C JD05 JD05A JD15C JK17A

Claims (1)

Claims 1. A fibrous aggregate is fixed to the back surface of a waterproof and flexible sheet substrate, and a water-absorbing swelling layer is formed on the back surface of the fiber aggregate. A self-healing waterproof sheet, characterized in that an alkali-soluble coating is provided on the back surface of the waterproof sheet.