JP3996999B2 - Water shielding sheet joint structure and inspection method for water shielding sheet joint - Google Patents

Description

【００３４】
表１の結果より、実施例では初期接着力および施工性に優れているとともに、２個所の接合部とも接合不良を検査することができる。それに対して比較例１では接合不良の検査は構造的には、接合材と遮水シートＡ、Ｂのそれぞれの間の接合部で検査が可能であるものの、初期接着力劣っているため加圧検査ができないという結果になった。また、比較例２では初期接着力と施工性では実施例と同等もしくはそれ以上の結果が出ているものの、接合材と遮水シートＡとの間の検査を行うことができず。接合不良に関し不安が残るということがわかる。
【００３５】
【発明の効果】
本発明の請求項１では接合部の欠陥を検査するための構造を有する遮水シート同士の接合部構造において、接合する遮水シート同士の間に接合材を介在させて融着しており、該接合材と遮水シートの融着部分には、接合部長手方向に伸びる融着部分に挟まれた未融着部分を設けることによって気密性通路を形成し、接合材は接合部の幅方向で１部材からなると共に少なくとも前記気密性通路において接合材の上下を連通する通気孔を接合材の長手方向に間隔をおいて複数形成してなることを特徴とする遮水シートの接合部構造である。
【００３６】
このような接合部構造とすることによって、二列の接合材を所定間隔をおいて配置するという作業を必要とせず、一つの接合材を配置すればよく、また、接合材の少なくとも未融着部分に通気孔を備えていることから接合材の上下を一度で検査することが可能である。
【００３７】
請求項２では、接合する遮水シート同士の間に接合材を介在させて融着しており、接合部には該接合部長手方向に伸びる融着部分に挟まれた未融着部分を設けることによって気密性通路を形成し、接合材は接合部の幅方向で１部材からなると共に少なくとも前記気密性通路において接合材の上下を連通する通気孔を接合材の長手方向に間隔をおいて複数形成してなり、遮水シートの接合部の気密性通路内を減圧もしくは加圧した後、気密性通路内の圧力の変動を検知することにより、遮水シート接合部の検査をする遮水シート接合部の検査方法である。
【００３８】
これは、請求項１の接合部構造を利用した接合部の検査方法であり、やはり、一度で接合部の上下両方を検査することができるという長所を有している。
また、請求項３では圧力の変動のあることを確認した後、接合部に石鹸水を塗布して気密性通路を加圧し、泡の発生を目視で確認することによって欠陥箇所を特定する遮水シート接合部の検査方法である。
【００３９】
このような検査方法を採ることによって、欠陥の有無を判定した後に、現場作業においても欠陥の箇所を目視で確認することができる
【図面の簡単な説明】
【図１】遮水シートの接合部構造の断面斜視図である。
【図２】遮水シートの接合部構造の断面図である。
【図３】接合材の斜視図である。
【図４】融着装置で融着しているところの斜視図である。
【図５】本発明の検査方法を実施している様子を示す平面図である。
【図６】従来の接合部構造の斜視図である。
【符号の説明】
１ 接合部
２ 接合材
３ 接合代
４ 気密性通路
５ 通気孔
６ 不定形シール材
７ 真空ポンプ
８ 挿入管[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for inspecting a defect of a water shielding sheet, and more particularly to an inspection method that does not place a burden on a joint and can easily determine the presence or absence of a defect.
[0002]
[Prior art]
In a landfill-type waste disposal site where industrial waste and general waste are dumped, in order to prevent sewage leaking from the disposal site from penetrating into the basement and causing environmental pollution, a water-impervious construction is installed at the bottom of the disposal site. Is required. Although various things are mentioned as a water-impervious construction, the method of laying the resin-made sheet | seat or the rubber-made water-impervious sheet | seat is often employ | adopted from the surface of certainty, safety, workability, and economical efficiency.
[0003]
In addition, in order to prevent water leakage, a water shielding sheet is laid on the bottom surface of a facility that stores water in a recess such as a reservoir, reservoir, or pool. Further, in underground structures and the like, a water shielding sheet may be laid over the structure in order to prevent groundwater from leaking into the structure.
[0004]
And since these water-impervious sheets are difficult to cover at once, it is difficult to cover the bottom of the water storage facility such as a waste disposal site or a reservoir having a vast area and the surroundings of the structure with a single water-impervious sheet. Construction that covers the entire surroundings of waste disposal sites, water storage facilities, and underground structures by joining and integrating on the site using a plurality of water shielding sheets is performed.
[0005]
However, in the method of joining such a water shielding sheet in the field, there is a case where a joint failure occurs in the joint part joined in the field, and there is a problem that sewage or stored water leaks from a defective portion due to the joint failure.
Conventionally, the proper inspection of the joint portion of the water shielding sheet is performed by performing an adhesion test of the joint portion by a sampling test, or at the construction site in the two water shielding sheets 12 and 13 at the water shielding sheet joint portion 11 as shown in FIG. The two rows of the bonding materials 14 and 15 are arranged, and air is pressed into the airtight passage 16 surrounded by the water shielding sheet and the two rows of the bonding materials, and the pressure is lowered after the pressure is maintained for a certain time. Otherwise, it was rated as no air outflow.
[0006]
In addition, when bonding a water shielding sheet using a bonding material made of a thermoplastic elastomer, the bonding material is previously fused to one water shielding sheet at a factory or the like and bonded to the other water shielding sheet at the site. The inspection of the joint portion is performed only on the joint portion on the side performed at the site.
[0007]
[Problems to be solved by the invention]
However, the operation of arranging the bonding material in two rows at the joint portion of the water shielding sheet and forming an airtight passage for performing the inspection with the water shielding sheet and the two rows of bonding material is performed by using two rows of bonding materials. This is not preferable because it requires careful and troublesome work in the field, such as having to be arranged at intervals, and this causes a reduction in work efficiency. In addition, there is a problem in that since the two rows of joining materials are connected by pressing the joint portion, the airtight passage is blocked, and the defect inspection of the joint portion cannot be performed. Moreover, in joining of a water shielding sheet by natural vulcanization of rubber, the initial adhesive force at the time of performing the joining work is small, and there is a current situation that it takes time to complete the adhesion.
[0008]
In addition, a bonding material is heat-sealed to one water-impervious sheet in advance at a factory, and the bonding material and the other water-impervious sheet are heat-bonded at the site. However, it cannot be said that the inspection is not complete because the part previously joined at the factory is not inspected.
[0009]
Therefore, it is conceivable that an unfused portion is also provided in the joint portion on the side to be thermally fused in advance, and the joint portions on both sides of the joining material are inspected, but the inspection must be performed twice. This will cause prolonged installation work on site.
Therefore, the present invention shows a sufficient initial adhesive force in the field, can easily provide an airtight passage for inspection without much labor, and is bonded to two waterproof sheets to be bonded. Provided is a water shielding sheet joint structure that allows two joints between materials to be inspected at once, and a joint inspection method using the same.
[0010]
[Means for Solving the Problems]
In Claim 1 of this invention, in order to achieve such an object, in the junction structure of the waterproof sheet which has a structure for inspecting the defect of a junction part, a bonding material is provided between the waterproof sheets to be joined. interposed therebetween are fused, the fused portion of the bonding material and the water shield sheet, an airtight passageway formed by providing a non-fused portion sandwiched fused portion extending joining the longitudinal direction of The bonding material is composed of one member in the width direction of the bonding portion, and at least a plurality of air holes communicating with the upper and lower sides of the bonding material in the airtight passage are formed at intervals in the longitudinal direction of the bonding material. It is the junction part structure of the water-impervious sheet.
[0011]
By adopting such a joint structure, it is not necessary to arrange two rows of bonding materials at a predetermined interval, and only one bonding material may be arranged, and at least unbonded bonding materials are used. Since the portion is provided with a vent hole, it is possible to inspect the top and bottom of the bonding material at a time.
[0012]
According to the second aspect of the present invention, bonding is performed by interposing a bonding material between the water shielding sheets to be bonded to each other, and an unfused portion sandwiched between fused portions extending in the longitudinal direction of the bonded portion is provided at the bonded portion. Thus, the airtight passage is formed, and the joining material is composed of one member in the width direction of the joining portion, and at least a plurality of vent holes communicating with the upper and lower sides of the joining material in the airtight passage are provided in the longitudinal direction of the joining material. After forming the air-tight passage in the air-tight passage at the joint of the water-impervious sheet, the water-impervious sheet for inspecting the water-impervious sheet joint by detecting pressure fluctuations in the air-tight passage This is a method for inspecting a joint.
[0013]
This is a method for inspecting a joint using the joint structure according to claim 1 and also has an advantage that both the upper and lower sides of the joint can be inspected at a time.
Further, in claim 3, after confirming that there is a fluctuation in pressure, water is applied to the joint portion to pressurize the airtight passage, and the water shielding is performed to identify the defective portion by visually confirming the generation of bubbles. It is an inspection method of a sheet joined portion.
By adopting such an inspection method, it is possible to visually confirm the location of the defect even in the field work after determining the presence or absence of the defect.
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a perspective view of a joint structure of a water shielding sheet according to the present invention, FIG. 2 is a sectional view of the joint structure, and FIG. 3 is a perspective view of a joining material.
The joining part 1 overlaps the edge part of the upper side water-impervious sheet A and the lower water-impervious sheet B, and interposes the joining material 2 between the overlapped parts. Joining between the respective water-impervious sheets A and B and the joining material 2 is performed by heat fusion, joining only the both ends of the joining part 1 in the width direction, and joining part 1 in the central part. The airtight passage 4 which is an unjoined portion extends along the longitudinal direction of the. This structure is adopted in both of the two joint portions between the upper water-impervious sheet A and the bonding material 2 and between the lower water-impervious sheet B and the bonding material 2.
[0015]
In addition, at least in the portion corresponding to the airtight passage 4 of the bonding material 2, the air holes 5 communicating the upper and lower sides of the bonding material 2 (the upper water shielding sheet A side and the lower water shielding sheet B side and both sides). Is provided over the entire length of the bonding material 2. As an operation for inspecting whether or not there is a bonding failure in the bonding portion 1 and identifying a bonding failure portion, the inside of the airtight passage 4 is depressurized or pressurized. At this time, by providing this vent hole 5 The upper and lower sides of the bonding material 2 can be inspected in one operation.
[0016]
Further, the joining material 2 is not particularly required to be in two rows, and only the both ends in the width direction of the joining material in one row can be heated, so that only the both ends can be fused with the water shielding sheet. Not something.
[0017]
In the present invention, materials that can be used as the material of the water shielding sheets A and B are EPDM (ethylene propylene rubber), HDPE (high density polyethylene), LDPE (low density polyethylene, PP (polypropylene), TPO (thermoplastic olefin), etc. The thickness is used in the range of 0.8 to 3.0 mm, and if it is less than 0.8 mm, the water shielding sheet is liable to be damaged due to insufficient strength, and if it exceeds 3.0 mm, there is a step in the joint. Since it becomes large, it is not preferable in terms of watertightness.
[0018]
The materials that can be used as the bonding material 2 are VLDPE (very low density polyethylene), LLDPE (linear low density polyethylene), MDPE (medium density polyethylene), HDPE (high density polyethylene), EVA (ethylene vinyl acetate), It is a thermoplastic elastomer such as EEA (ethylene ethyl acrylate), TPO (thermoplastic olefin) or a copolymer of α-olefin. As the thickness of the bonding material 2, a thickness of 0.8 to 3.0 mm can be used, and if it is less than 0.8 mm, there is a problem that insufficient bonding force or poor bonding is likely to occur, exceeding 3.0 mm. The two rows of the bonding material 2 are connected to each other to block the airtight passage 4 and in some cases the inspection work cannot be performed, or the volume of the airtight passage 4 becomes too large, and the inside of the airtight passage 4 is decompressed.・ It takes too much time to pressurize. There was a problem that the level difference of the joint portion became large and a problem occurred in terms of water tightness.
[0019]
The vent hole 5 provided in the bonding material 2 is not particularly limited in form, but for example, a circular hole having a diameter of about 3 to 10 mm is provided near the center in the width direction of the bonding material 2 at a predetermined pitch in the longitudinal direction, or a small diameter. And the like in which a large number of holes are randomly provided.
[0020]
In this method, an unbonded portion is provided between the bonding material 2 and the water-impervious sheets A and B. For example, a melt having two heating irons 10 disposed between the connecting portions 9 that do not perform heating as shown in FIG. A method of heat-bonding using a dressing device, or pasting a non-woven fabric or woven fabric made of a material having a high melting point such as glass fiber on a portion corresponding to the unbonded portion of the bonding material 2 or the water shielding sheets A and B in advance. Various methods such as a method of fusing only a portion without a non-woven fabric by heating can be employed. Further, the bonding material 2 may be previously bonded to one water-impervious sheet at a factory or the like.
[0021]
The width of the fused portion occupying the width of the bonding material 2 is in the range of 5 to 15 mm. If the thickness is less than 5 mm, the bonding force becomes insufficient or a defective bonding portion is likely to occur. If the thickness exceeds 15 mm, the width of the bonding portion becomes too wide.
[0022]
On the other hand, the width of the airtight passage 4 which is an unjoined portion is 5 to 25 mm, and is less than 5 mm, or the airtight passage 4 becomes too narrow and insertion of an insertion tube for inspection becomes difficult. There is a problem, and if it exceeds 25 mm, the volume of the airtight passage 4 becomes too large, and it takes too much time to depressurize and pressurize the inside of the airtight passage 4, which is not preferable.
[0023]
Next, a method for inspecting the joint using the above-described joint structure of the water shielding sheet will be described.
As shown in FIG. 5, the joining portion 1 provided by the above method is divided into a predetermined length along the longitudinal direction of the joining portion (for example, about several meters to several tens of meters is divided into one section, In order to provide airtightness, the airtight passage 4 is filled with an indeterminate shaped sealing material 6 or is sandwiched by grip pliers, etc. (not shown). As shown in FIG. 5, the insertion tube 8 of the pressurizing pump 7 for pressurizing the airtight passage 4 is inserted.
[0024]
Then, air is blown into the airtight passage 4 by the pressurizing pump 7 to bring it into a pressurized state. Thereafter, after a predetermined time has passed in the pressurized state, the pressure gauge is read, and if the pressure is changed, it can be seen that there is a joint defect portion somewhere in the section.
[0025]
In order to inspect the presence or absence of a defective portion, the inside of the airtight passage 4 may be decompressed, and a vacuum pump is used instead of the pressurizing pump. In the case of pressurization, since the pressure cannot be increased too much due to fear of peeling of the joint portion, one inspection section is shortened. Therefore, in consideration of the efficiency of the inspection work, the inspection by the reduced pressure is preferable.
[0026]
If the compartment with the defective portion can be identified, the airtight passage at the joint in the compartment containing the defective portion is next pressurized with a pressure that swells when seen from the outside. And if the state of a junction part is observed and abnormality of a fusion | melting location is discovered, it can specify that the location is a defect location.
[0027]
As another method for identifying the defective portion, soap water is applied to the entire joint portion in the section including the defective portion, and the inside of the airtight passage is pressurized. And if the state of a junction part is observed and the bubble generation | occurrence | production location of soap water is discovered, it will be understood that the location is a defective location.
[0028]
In order to depressurize the airtight passage, it is necessary to use a vacuum pump. However, the pressurizing pump may be replaced with a depressurizing vacuum pump, or a pump that can switch between depressurizing and pressurizing originally. May be used.
[0029]
【Example】
Next, when the joint structure of the water-impervious sheet of the present invention was used, comparison of initial adhesive strength and workability, and comparison of inspectable portions of the joint portions were performed.
As an example, a water shielding sheet A, B made of vulcanized EPDM and a bonding material having a width of 70 mm and a thickness of 1.5 mm made of polypropylene are used. What was melt | fused to the water-impervious sheet A at the factory in the state which took the unfused part corresponding to the airtight path | pass for 30 mm at the direction both ends by 10 mm width was used. Then, using the fusing device as shown in FIG. 4, the other water-impervious sheet A is fused with a bonding margin of 12 mm at both ends in the width direction and an unfused portion corresponding to the airtight passage with a width of 20 mm. We joined.
[0030]
As Comparative Example 1, water-impervious sheets A and B made of vulcanized EPDM were bonded with a natural vulcanized rubber tape having a width of 50 mm and a thickness of 1.0 mm made of butyl rubber, and one end of the water-impervious sheet A was airtight. In order to provide the passage, the joining materials were arranged in two rows at intervals of 20 mm, and the other water-impervious sheet B was overlapped and joined from above.
[0031]
As Comparative Example 2, a bonding material having a width of 70 mm and a thickness of 1.5 mm made of polypropylene was applied in advance to the end of a water shielding sheet B made of vulcanized EPDM. An airtight passage composed of an unfused portion was provided on the side, and fusion bonded.
[0032]
Measure the initial (30 minutes later) adhesive strength and the adhesive strength after aging (7 days) between the two water shielding sheets A and B to be joined to each of the above Examples and Comparative Examples 1 and 2, respectively. The ease of construction was confirmed, and whether or not inspection was possible at two joints between the joining material and the two water shielding sheets A and B was confirmed. Whether or not the inspection was possible was judged on the premise that the pressure fluctuation was confirmed by holding at an air pressure of 0.5 kgf / cm ² for 1 minute. The results are shown in Table 1.
[0033]
[Table 1]

[0034]
From the results of Table 1, in the examples, the initial adhesive force and the workability are excellent, and the bonding failure can be inspected at the two joint portions. On the other hand, in Comparative Example 1, the inspection of the bonding failure is structurally possible at the bonding portion between the bonding material and the water shielding sheets A and B, but the initial adhesive force is inferior, so pressurization is performed. The result was that it could not be inspected. Further, in Comparative Example 2, although the initial adhesive force and workability are equal to or higher than those in the example, the inspection between the bonding material and the water shielding sheet A cannot be performed. It can be seen that anxiety remains about the bonding failure.
[0035]
【The invention's effect】
In claim 1 of the present invention, in the joint structure between the water-impervious sheets having a structure for inspecting the defect of the joint part, the bonding material is interposed between the water-impervious sheets to be joined, and is fused . An airtight passage is formed by providing an unfused portion sandwiched between fusion portions extending in the longitudinal direction of the joint portion in the fusion portion of the joining material and the water shielding sheet, and the joining material is formed in the width direction of the joint portion. A joint structure for a water shielding sheet, comprising a single member and a plurality of air holes communicating at the upper and lower sides of the joining material at least in the longitudinal direction of the joining material in the airtight passage. is there.
[0036]
By adopting such a joint structure, it is not necessary to arrange two rows of bonding materials at a predetermined interval, and only one bonding material may be arranged, and at least unbonded bonding materials are used. Since the portion is provided with a vent hole, it is possible to inspect the top and bottom of the bonding material at a time.
[0037]
According to the second aspect of the present invention, bonding is performed by interposing a bonding material between the water shielding sheets to be bonded to each other, and an unfused portion sandwiched between fused portions extending in the longitudinal direction of the bonded portion is provided at the bonded portion. Thus, the airtight passage is formed, and the joining material is composed of one member in the width direction of the joining portion, and at least a plurality of vent holes communicating with the upper and lower sides of the joining material in the airtight passage are provided in the longitudinal direction of the joining material. After forming the air-tight passage in the air-tight passage at the joint of the water-impervious sheet, the water-impervious sheet for inspecting the water-impervious sheet joint by detecting pressure fluctuations in the air-tight passage This is a method for inspecting a joint.
[0038]
This is a method for inspecting a joint using the joint structure according to claim 1 and also has an advantage that both the upper and lower sides of the joint can be inspected at a time.
Further, in claim 3, after confirming that there is a fluctuation in pressure, water is applied to the joint portion to pressurize the airtight passage, and the water shielding is performed to identify the defective portion by visually confirming the generation of bubbles. It is an inspection method of a sheet joined portion.
[0039]
By adopting such an inspection method, after determining the presence or absence of defects, it is possible to visually confirm the location of defects in field work. [Brief description of drawings]
FIG. 1 is a cross-sectional perspective view of a joint structure of a water shielding sheet.
FIG. 2 is a cross-sectional view of a joint structure of a water shielding sheet.
FIG. 3 is a perspective view of a bonding material.
FIG. 4 is a perspective view showing a state where fusion is performed by a fusion apparatus.
FIG. 5 is a plan view showing a state in which the inspection method of the present invention is performed.
FIG. 6 is a perspective view of a conventional joint structure.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Junction part 2 Joining material 3 Joining allowance 4 Airtight passage 5 Vent hole 6 Indeterminate sealing material 7 Vacuum pump 8 Insertion pipe

Claims (3)

At the junction structure of the water shield sheets each having a structure for inspecting defects of the joint, it is fused by interposing a bonding material between the water shield sheets between the joining, the joining director the junction An airtight passage is formed by providing an unfused portion sandwiched between fusion portions extending in the hand direction, and the joining material is composed of one member in the width direction of the joining portion, and at least the upper and lower portions of the joining material in the airtight passage. A joint structure for a water shielding sheet, wherein a plurality of air holes communicating with each other are formed at intervals in the longitudinal direction of the joining material . The bonding material between the water shield sheet between the bonding is interposed and fused, the airtightness passage by providing a non-fused portion sandwiched fused portion extending into the joint the longitudinal direction of the joint The bonding material is formed of one member in the width direction of the bonding portion and at least a plurality of vent holes communicating with the upper and lower sides of the bonding material in the airtight passage at intervals in the longitudinal direction of the bonding material, Method of inspecting a water shielding sheet joint by inspecting the water shielding sheet joint by detecting pressure fluctuations in the airtight passage after reducing or pressurizing the inside of the airtight passage at the joint of the water shielding sheet . 3. The water shielding sheet according to claim 2 , wherein after confirming that there is a fluctuation in pressure, a defective portion is specified by applying soapy water to the joint, pressurizing the airtight passage, and visually confirming the generation of bubbles. Inspection method for joints.

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