JP2007203161A - Joining method of impervious sheet and joint structure of the sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To propose a joining method of an impervious sheet with excellent water barrier properties allowing convenient and inexpensive underwater construction and a joint structure of an impervious sheet suitable for the joining method. <P>SOLUTION: The joint structure of the impervious sheet is constructed by a joining method of the sheet having a first process of adhering a heat-activatable closed-cell foam sheet 3 to the end of the impervious sheet 1, a second process of laying underwater two or more impervious sheets 1 adhered with the closed-cell foam sheet 3 at the end and a third process of placing a cut-off material 2 which allows formation into any shape and shows following properties at ordinary temperature and melts on heating so as to extend over the joined part (a) of the impervious sheets 1 and 1 mutually adjacent in a molten state and adhering the cut-off material 2 to the end of the impervious sheets 1. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a joining method for a water shielding sheet laid in water and a joining structure for a water shielding sheet constituted thereby.

For example, in a sea surface disposal site where waste is reclaimed in the sea area, a water shielding sheet is formed by laying a water shielding sheet in a predetermined area surrounded by a partition formed in the sea, and sewage containing harmful substances, etc. Is prevented from leaking outside.
In addition, a water shielding layer formed by a water shielding sheet may be used also in a reservoir, a reservoir, or the like.

  Joining of the water shielding sheets accompanying the formation of the water shielding layer has been performed on land (in the air) by a thermal welding method, an adhesion method using an adhesive, or the like. However, for example, when a water shielding sheet is laid in a wide area, such as a sea surface disposal site, it is difficult to transport and lay (lay) a water shielding sheet joined on land to the site.

For this reason, conventionally, when constructing such a large area impermeable layer, a float or the like is installed on the impermeable sheet, and the impermeable sheets are joined to each other while floating on the sea surface. When completed, the float was removed, and a water-impervious sheet was laid on the seabed (water bottom).
In addition, as another conventional method for joining water-impervious sheets, there has been performed a method for stopping water by pouring asphalt mastic or the like into a joint between water-impervious sheets in water.

  However, the above-described method for constructing a water shielding layer using a float requires time and labor for installing the float on the water shielding sheet, collecting the float at the time of laying, and laying the sheet at a fixed position. However, there is a problem that it is difficult to lay so that wrinkles are not formed.

In addition, the water stop method using asphalt mastic is that the water shielding sheet and the asphalt mastic adhere to each other, but they do not adhere to each other. Asphalt mastic was separated, and there was a problem that the water shielding property might be lowered.
Here, “adhesion” in this specification refers to a state of being in contact with no gap, and may be a state of physical bonding (adhesion) or a state of only contact.

  Therefore, in Patent Document 1, a housing portion capable of containing air or a weight body is formed by partially doubling the water shielding sheet, and when the water shielding sheets are joined together, air is contained in the housing portion. When laying the water-impervious sheet, put a weight body in the housing part, sink it to the bottom of the water, sink it to the bottom of the water, and then discharge the weight body from the housing part. A method of forming a water shielding layer is disclosed.

Further, in Patent Document 2, after a water-impervious sheet having at least an end corresponding to a joint portion made of an asphalt material is sunk in the bottom of the water, asphalt mastic or the like is poured into the joint between adjacent water-impervious sheets. By this, the method of integrating a water-impervious sheet and an asphalt mastic in the junction part of water-impervious sheets is disclosed.
Japanese Patent Laying-Open No. 2003-211115 ([0027]-[0030], FIG. 5 to FIG. 6) Japanese Patent Laying-Open No. 2003-033745 ([0008]-[0010], FIGS. 1 to 4)

  However, the method for forming a water-shielding layer described in Patent Document 1 requires labor and material costs at the production stage of the water-shielding sheet by forming the housing part by partially forming the water-shielding sheet as a double layer. Due to the increase, the construction cost becomes expensive. In addition, there are problems such as troublesome insertion of air into the housing portion, insertion and discharge of weights, and the like.

  Further, the method for joining the water shielding sheets described in Patent Document 2 is that the water shielding sheet is made more flexible than a known water shielding sheet made of rubber or the like because at least a part of the water shielding sheet is made of an asphalt material. In addition to inferior properties and the like, the weight becomes heavier, so that handling at the time of transportation and laying becomes complicated, resulting in inferior workability.

  From such a point of view, the present invention can be easily and inexpensively constructed in water and has a water shielding sheet with excellent water shielding properties, and a water shielding sheet suitably used for this water shielding sheet joining method. It is an object to propose a joint structure.

  In order to solve such a problem, the present invention includes a step of adhering a heat-weldable foam sheet to an end portion of a water-impervious sheet, a step of laying a plurality of the water-impervious sheets in water, and adjacent to each other. In a state of straddling the joint between the water shielding sheets, a step of closely attaching a water stop material to an end of the water shielding sheet to which the foam sheet is bonded, The water-stopping material is a material that can be molded into an arbitrary shape at room temperature and has a performance of melting by heating, and the water-stopping material is in close contact with the end of the water-blocking sheet in a molten state. It is a feature.

  Such a method for joining the water shielding sheets is completed simply by laying the water shielding sheets in the water and placing the water blocking material in close contact with the end portions of the water shielding sheets at the joints between the water shielding sheets in the water. Therefore, it is excellent in workability. In other words, since the water shielding sheet is laid before joining, the water shielding sheet can be arranged at a predetermined position without forming wrinkles, so a high quality water shielding layer is easily formed on the bottom of the water. can do. Moreover, what is necessary is just to select and use from a well-known water-impervious sheet for a water-impervious sheet, and material cost is cheap. Furthermore, the water-stop material and the water-impervious sheet are separated by being melted by the heat of the water-stop material in the melted state and bonded together through a foam sheet that physically adheres to the water-stop material. There is nothing and it is excellent in water shielding. In the present specification, “thermal weldability” refers to a property of being melted by heat and physically bonded.

  In the water shielding sheet bonding method, the water blocking material is made of asphalt mastic, and if the water blocking material is arranged by pouring, the asphalt mastic is cooled and hardened to complete the bonding of the water blocking sheet. Therefore, it is excellent in workability.

  Further, if the water shielding sheet joining method includes a step of forming a groove for pouring the water-stopping material by placing a pair of outflow prevention members across the joint, the asphalt mastic is, Since it is arranged in a state in which it does not flow out in the lateral direction and maintains a necessary thickness, it is preferable that water impermeability is not impaired.

  In addition, if the outflow prevention member is made of a hardened body made of asphalt mastic, it is softened by the heat of the poured asphalt mastic, so that the shape of the foundation can be obtained even when the flatness of the installation base of the water shielding sheet is poor. It is preferable to creep so as to follow and prevent the asphalt mastic from flowing out.

  Further, if a partition member that divides the groove at a predetermined interval is disposed, even if the installation location of the water shielding sheet is a slope portion, it is possible to prevent the asphalt mastic from flowing down, and to prevent the water from blocking. Asphalt mastic can be arranged while maintaining the required thickness.

  In the water shielding sheet joining method, the water blocking material is a block material made of asphalt mastic cured with heating means such as an electric heater or a hot oil heater embedded therein, and the block material is predetermined. After arrange | positioning in a location, a block material may be heated with a heating means and a water stop material may be closely_contact | adhered to the edge part of the said water shielding sheet. According to this method, the water shielding sheet can be easily joined without being constrained by the state of the installation base of the water shielding sheet (planar surface, inclined surface, non-flat surface, etc.). In addition, it does not require equipment to be transported while maintaining the fluidity of asphalt mastic, so that construction with simple equipment is possible.

  The joining method of the water shielding sheet may include a step of adhering a granular material made of an asphalt mixture to the upper surface of the foamed sheet in a heated state before the water shielding sheet is laid in water.

According to such a water shielding sheet joining method, a granular material made of an asphalt mixture (hereinafter sometimes simply referred to as “granular ascon”) is bonded in advance to the upper surface of the foamed sheet, and therefore, a water stop made of asphalt mastic. When the material adheres to the waterproof sheet, the granular ascon is melted by the heat of the waterproof material and is bonded together with the waterproof material, so that the waterproof material and the waterproof sheet are more strongly bonded. In addition, the weight of the granular ascon bonded to the foamed sheet makes it possible to prevent fluttering of the impermeable sheet due to waves or the like when the impermeable sheet is laid in water, thereby facilitating laying work.
The granular ascon may be adhered to the foamed sheet before or after the foamed sheet is adhered to the water shielding sheet.

  Moreover, the joining structure of the water-impervious sheet of the present invention has two water-impervious sheets arranged side by side, and a heat-weldability that is bonded in advance to the other water-impervious sheet side end of the water-impervious sheet. It is composed of a foam sheet and a water-stopping material that is in close contact with the two water-impervious sheets in a state of straddling the joint between the two water-impervious sheets and bonded to the foam sheet. It is characterized by that.

  According to the joining structure of the water shielding sheet, the foam sheet adhered to the water shielding sheet is melted by the heat of the melted water sealing material, and the water shielding sheet and the water sealing material are physically bonded. Therefore, even if deformation occurs in the installation base such as ground subsidence, the water shielding property at the joint portion does not decrease.

  Moreover, if the joining structure of the water shielding sheet includes a cured body made of asphalt mastic arranged so as to sandwich the water blocking material from both ends, the water blocking material maintains a thickness necessary for water blocking. It is suitable because it is arranged in the state.

  According to the water shielding sheet joining method and the water shielding sheet joining structure of the present invention, it is possible to perform construction in water easily and inexpensively and to form a water shielding layer having excellent water shielding properties.

Hereinafter, the best mode for carrying out the water shielding sheet joining method and the water shielding sheet joining structure according to the present invention will be described in detail with reference to the accompanying drawings. This embodiment demonstrates the case where a water-impervious sheet is formed in a water bottom by the water-impervious sheet joining method and water-impervious sheet joining structure of the present invention in a sea surface disposal site.
Here, FIG. 1 is a perspective view showing an outline of the sea surface disposal site according to the first to third embodiments. FIG. 2 is a transverse cross-sectional view showing a watertight sheet joining structure according to the first embodiment. Moreover, FIG. 3 is a figure which shows the joining structure of the water shielding sheet | seat which concerns on 2nd Embodiment, (a) is a longitudinal cross-sectional view, (b) is a cross-sectional view. Moreover, FIG. 4 is a cross-sectional view showing a watertight sheet joining structure according to the third embodiment. Furthermore, FIG. 5 is a cross-sectional view showing a part of the joint structure of the water shielding sheet according to the fourth embodiment.

<First Embodiment>
In the first embodiment, as shown in FIG. 1, the water shielding layer 11 is formed by laying the water shielding sheet 1 so as to cover the water bottom in a predetermined range surrounded by the caisson revetment 20 or the like, The case where the sea surface disposal site 10 is formed will be described.

  The sea surface disposal site 10 surrounds a predetermined area by the caisson revetment 20, and the bottom surface of the inner water area so that harmful substances are not discharged from the waste dumped in the sea surface disposal site 10 to the surrounding ground or the outer water area B. And the wall surface are covered with a water shielding layer 11.

  The caisson revetment 20 includes a caisson 21, a rubble mound 22, and a back layer 23. The caisson 21 is a reinforced concrete member having a rectangular shape in cross section, and is constructed on the upper surface of the rubble mound 22 so that its upper end protrudes from the water surface. The rubble mound 22 is formed by raising the base G in a trapezoidal manner in the form of a chestnut or crushed stone. The backfill layer 23 is formed on the inner water area A side of the caisson revetment 20 by raising crushed stones, crushed stones and the like in a slope shape with a predetermined inclination.

In addition, in 1st Embodiment, it was set as the structure which surrounds the circumference | surroundings of the sea surface disposal site 10 by the caisson revetment 20, However, The formation method of the sea surface disposal site 10 is not limited to the said method, For example, a sheet pile revetment is used. What is necessary is just to form using a well-known structure suitably, such as using.
Further, the backfill layer 23 is formed on the inner water area A side of the caisson 21, but it goes without saying that the backfill layer 23 may be formed as necessary.
Furthermore, the materials used for forming the rubble mound 22 and the backfill layer 23 are not limited, and may be appropriately selected from known materials. The rubble mound 22 and the backfill layer 23 may be It may be formed of the same material or different materials. Moreover, about the rubble mound 22 or the backfill layer 23, you may give water-stopping property by making asphalt mastic etc. penetrate | penetrate in the clearance gap between the raised chestnut and the crushed stone.

  The water shielding layer 11 includes a plurality of water shielding sheets 1, 1,... Arranged side by side so as to cover the bottom surface (base G) and the wall surface (backfill layer 23) of the sea surface disposal site 10. It is formed by joining adjacent water-impervious sheets 1 to each other via a sheet joining structure (hereinafter sometimes simply referred to as “joining structure”) S.

As shown in FIG. 2, the joining structure S <b> 1 (joining structure S) according to the first embodiment includes the water shielding sheets 1, 1 arranged side by side and another water shielding sheet of the water shielding sheets 1, 1. In the end part on the 1 side, the foamed sheets 3 and 3 as heat-weldable foam sheets bonded in advance, respectively, and the adjacent water-impervious sheets 1 and 1 so as to straddle the joint part a, And the water stop material 2 arrange | positioned so that the said independent foam sheet 3 may be covered is comprised.
Furthermore, in the first embodiment, the outflow prevention materials 4 and 4 which are block members (cured bodies) made of asphalt mastic are disposed so as to sandwich the water stop material 2 from both ends.

The water-impervious sheet 1 prevents outflow of contaminants and the like from the sea surface disposal site 10 to the outside. As shown in FIG. 1 and FIG. The water shielding layer 11 is formed by bonding.
As the water shielding sheet 1, a rubber sheet made of ethylene propylene diene monomer rubber (EPDM) having a thickness of 2 mm is used. The material constituting the water shielding sheet 1 is not limited to an EPDM rubber sheet. For example, a rubber sheet obtained by co-vulcanization of EPDM and butyl rubber (IIR), or a plastic material such as vinyl chloride resin (PVC). A plastic sheet with added flexibility by adding an agent, a sheet containing EPDM as a main component and special rubber, a sheet containing high-density polyethylene (HDPE) polymerized at low temperature and low pressure, and a weathering agent In addition, polypropylene (PPA) may be selected from well-known water shielding sheets, such as a sheet of a material in which polypropylene (PPA) is mainly finely dispersed during raw material polymerization.

The water blocking material 2 shields the joint part a for the purpose of preventing the outflow of contaminants and the like from the gaps between the joint parts a of the water shielding sheets 1 and 1 arranged side by side. As shown in FIG. 2, the water blocking material 2 shields the joint portion a by being in close contact with the water shielding sheet 1.
As the water-stopping material 2, a material that melts by heating and can be formed into an arbitrary shape at room temperature and has followability is used. In the first embodiment, asphalt mastic is used. The blending of asphalt mastic 2 is not limited, but for example, 70% by mass of stone powder with respect to 30% by mass of asphalt or 30% by mass of stone powder with respect to 20% by mass of asphalt and 50% by mass of sand. And those having a composition that can be cast without requiring compaction, such as those having a mass of 15% by mass of asphalt and those having a mass of 25% by mass of stone, 20% by mass of sand, and 40% by mass of crushed stone. Moreover, it cannot be overemphasized that the water stop material 2 is not limited to asphalt mastic.

As shown in FIG. 2, the independent foam sheet 3 is an end portion of the water-insulating sheet 1, for the purpose of integrally bonding the water-insulating sheet 1 and the water-stopping material 2. It is bonded to the contact point. And it melts by the heat | fever at the time of the close_contact | adherence to the water-impervious sheet | seat 1 of the water stop material 2, and adhere | attaches the water stop material 2 physically.
For the independent foamed sheet 3, a continuous foam having no continuity is dispersed innumerably and has heat-weldability, and a foaming ratio of 2 to 60 times is used. In the first embodiment, the closed foam sheet 3 is used as the foam sheet in consideration of water stoppage. However, the type of the foam sheet is limited as long as it has heat-weldability. It is not something. Moreover, although the material of the independent foam sheet 3 is not limited, For example, an independent foam polyethylene sheet, an independent foam polypropylene sheet, an independent foam polyethylene-vinyl acetate copolymer sheet, etc. can be used.

  As shown in FIG. 2, the spill preventive material 4 is disposed in advance on both sides of the place where the water proof material 2 is disposed along the joint portion a in order to prevent the water proof material 2 from flowing out in the lateral direction (in FIG. 2). Left and right). That is, the pair of outflow prevention materials 4 and 4 are arranged so as to face each other with the independent foam sheets 3 and 3 bonded to the respective end portions of the water shielding sheets 1 and 1 adjacent to each other interposed therebetween. Yes.

  The material constituting the outflow prevention material 4 is not limited as long as it can prevent the outflow of the water blocking material 2, but in the first embodiment, the asphalt mastic is cured into a prismatic shape. The block member comprised by these shall be used. In addition, since the mix | blending etc. of the asphalt mastic which comprises the outflow prevention material 4 can use the same thing as what was used in description of the water stop material 2, detailed description is abbreviate | omitted. Needless to say, a known material such as a steel plate or a concrete block may be appropriately used as the outflow prevention material 4. Further, the outflow prevention material 4 may be bonded to the water shielding sheet 1 in advance.

  Next, a method for joining the water shielding sheets according to the first embodiment will be described.

  The water shielding sheet joining method according to the first embodiment includes (1) a foam sheet bonding step, (2) a water shielding sheet laying step, (3) an outflow prevention material arranging step, and (4) a water stoppage. And a material arranging step.

(1) Foam sheet adhesion process The foam sheet adhesion process is a process of adhering the heat-weldable independent foam sheet 3 to the end of the water-impervious sheet 1 on the joining part a side (see FIG. 2). Before laying the sheet 1 underwater, it is performed in the air (land, etc.).

(2) Water-impervious sheet laying step The water-impervious sheet laying step is a step of lining the water-impervious sheet 1 with the independent foamed sheet 3 bonded to the end thereof in the foam sheet adhering step. And laying on the bottom surface (base G) (see FIG. 1).

(3) Outflow prevention material arrangement process The outflow prevention material arrangement process is a pair of outflow prevention with the joint a between the impermeable sheets 1 and 1 laid in the sea surface disposal site (underwater) 10 in the impermeable sheet laying process. This is a step of arranging the materials 4 and 4 and forming a groove for pouring the water-stopping material 2. In addition, the outflow prevention materials 4 and 4 have a shape that does not move due to the pressure of the poured water-stopping material 2, and are substantially equal to the thickness of the water-stopping material 2 necessary for shielding the joint portion a. It is formed in a shape having a thickness (see FIG. 2).

(4) Water-stopping material placement step The water-stopping material placement step is to pour the water-stopping material (asphalt mastic) 2 having fluidity by being heated to 110 to 190 ° C in the grooves formed in the outflow prevention material placement step. This is a step of bringing the water blocking material 2 into close contact with the end portion of the water shielding sheet 1 (see FIG. 2). By pouring the water blocking material 4 so as to be in close contact with the end portion of the water shielding sheet 1, the independent foam sheet 3 adhered to the end portion of the water blocking sheet 1 comes into contact with the water blocking material 2, and the water blocking material 2 This contact surface is melted by the heat of 2. Thereby, a discontinuous uneven surface is formed on the contact surface of the independent foam sheet 3 with the waterstop material 2. And since the water stop material 2 and the independent foam sheet 3 mesh when the water stop material 2 enters into the recesses of the discontinuous uneven surface of the independent foam sheet 3, the water stop material 2 and the independent foam sheet 3 are Glue physically. Thereby, the water-impervious sheet 1 and the water stop material 2 are bonded together. Moreover, since the block member made of asphalt mastic which is the outflow prevention member 4 creeps due to the heat of the water blocking material 1 poured into the groove, the water shielding sheet 1 and the outflow prevention material are formed even on a base having poor flatness. No gap is formed between the water stop material 4 and the water stop material 2 does not flow out in the lateral direction.

  As mentioned above, according to the joining method of the water shielding sheet concerning a 1st embodiment, it becomes possible to constitute joining structure S1 excellent in water shielding in water.

  According to joining structure S1 concerning a 1st embodiment, in order to shield joint part a of impermeable sheets 1 with water-stopping material 2 poured in, water in sea surface disposal site 10 etc. from joint part a ( (Including pollutants) does not flow out and has excellent safety.

  Moreover, since the water-impervious sheet 1 and the water blocking material 2 are in close contact with each other without a gap, the water-impervious sheet 1 and the water-stopping material 2 are excellent in water impermeability. In addition, even if deformation occurs in the foundation such as ground subsidence, the water shielding sheet 1 and the water blocking material 2 are bonded by the independent foam sheet 3, so that the water shielding performance can be maintained without being separated. It is said.

  According to the joining method of the water shielding sheet according to the first embodiment, since the outflow prevention material 4 is arranged, the thickness necessary for water shielding of the water blocking material 2 designed in the joint portion a is maintained. Since it can be applied in a state, it is possible to form the water shielding layer 11 excellent in water shielding.

  Since the water-impervious sheets 1 and 1 can be reliably joined in water, a large cross-section can be obtained by joining the water-impervious sheets 1 in advance on land or when submerging after joining via a float on the surface of the water. Compared with the case of laying down the water-impervious sheet, etc., it is possible to greatly save labor, and construction can be performed easily. In addition, since no special materials or construction machines are required for construction, the cost can be reduced, and inexpensive construction is possible.

<Second Embodiment>
2nd Embodiment demonstrates the case where the joining structure S of the water shielding sheet | seat which concerns on this invention is applied to the water shielding layer 11 formed in slope shape, such as backfilling, in the sea surface disposal site 10 shown in FIG. To do.

  Since the sea surface disposal site 10 according to the second embodiment and the caisson revetment 20 for forming the sea surface disposal site 10 are the same as those described in the first embodiment, detailed description thereof is omitted.

As shown in FIGS. 3A and 3B, the joining structure S2 according to the second embodiment includes the water shielding sheets 1 and 1 arranged side by side and the other water shielding sheets 1 and 1. The heat-weldable independent foamed sheets 3 and 3 that are bonded in advance to the end portion of the water sheet 1 and the joints a between adjacent water-impervious sheets 1 lie side by side, and the independent The waterproofing material 2 is disposed so as to cover the foamed sheet 3, and the pair of outflow prevention materials 4 ′ and 4 ′ are disposed so as to sandwich the waterproofing material 2 from both ends.
Furthermore, in the joining structure S2 according to the second embodiment, as shown in FIG. 3A, the partition members 5, 5,... Are spaced at a predetermined interval between the pair of outflow prevention members 4 ′, 4 ′. It is comprised by arrange | positioning.

  The water-impervious sheet 1 prevents outflow of contaminants and the like from the sea surface disposal site 10 to the outside. As shown in FIGS. 1 and 3, a plurality of sheets are arranged side by side to form a joining structure S (S2). The water shielding layer 11 is formed by joining together. In addition, since the water shielding sheet 1 used by joining structure S2 which concerns on 2nd Embodiment is the same as that of what was demonstrated in 1st Embodiment, detailed description is abbreviate | omitted.

  The water blocking material 2 shields the joint part a for the purpose of preventing the outflow of contaminants and the like from the gaps between the joint parts a of the water shielding sheets 1 and 1 arranged side by side. As shown in FIG. 3B, the water blocking material 2 shields the joint portion a by being in close contact with the water shielding sheet 1. In addition, since the water stop material 2 used by joining structure S2 which concerns on 2nd Embodiment uses the thing similar to what was demonstrated in 1st Embodiment, detailed description is abbreviate | omitted.

  The independent foamed sheet 3 is an end portion of the water shielding sheet 1 for the purpose of bonding the water shielding sheet 1 and the water blocking material 2 together, as shown in FIG. The water-stopping material 2 is melted by heat when closely attached to the water-impervious sheet 1 and physically bonded to the water-stopping material 2. In addition, since the independent foam sheet 3 used by joining structure S2 which concerns on 2nd Embodiment uses the thing similar to what was demonstrated in 1st Embodiment, detailed description is abbreviate | omitted.

  As shown in FIG. 3 (b), the outflow prevention member 4 ′ is arranged in advance on both sides of the water stop material placement location along the joint portion a in order to prevent the water stop material 2 from flowing out in the lateral direction. It is what is done. That is, the pair of outflow prevention materials 4 ′ and 4 ′ are arranged so as to face each other with the independent foam sheets 3, 3 bonded to the respective end portions of the adjacent water shielding sheets 1, 1 sandwiched therebetween. Has been.

  The material constituting the outflow prevention material 4 ′ is not limited as long as it can prevent the outflow of the water blocking material 2, but in the second embodiment, a steel plate is used. Here, in the first embodiment, a hardened body of asphalt mastic is used as the outflow prevention material 4, and when the flatness of the base G is poor, the base G is creeped by the heat of the water stop material 2. In the second embodiment, since the joining structure S2 is constructed in the backfill layer 23 formed in a slope shape in a state where flatness is ensured, the outflow prevention material 4 is configured to follow the unevenness. 'No need to expect a follow-up function. Therefore, even if the outflow prevention material 4 ′ is made of a steel member, the outflow prevention function of the water blocking material 2 can be sufficiently exhibited. Needless to say, a known material such as a block member or a concrete block made of a hardened asphalt mastic may be used as the outflow prevention material 4 '.

  As shown in FIG. 3A, the partition member 5 is disposed so as to divide a groove formed by the pair of outflow prevention materials 4 ′ and 4 ′ at a predetermined interval along the outflow prevention material 4 ′. The member is made of a steel plate. By arranging the partition member 5 in this way, the water-stopping material 2 having fluidity arranged in a slope shape is prevented from flowing down.

The material constituting the partition member 5 is not limited as long as it can prevent the waterstop material 2 from flowing down, but in the second embodiment, the steel plate is the same as the outflow prevention material 4 ′. Shall be used. And in 2nd Embodiment, outflow prevention material 4 'and the partition member 5 are joined mutually, and it is comprised so that it may not fall down by the pressure of the poured water stop material 2. FIG.
Needless to say, the outflow prevention member 4 ′ and the partition member 5 may be configured by members each having a thickness capable of being erected without being joined. In the second embodiment, the outflow prevention member 4 ′ and the partition member 5 are made of the same material, but it goes without saying that they may be made of different materials.

  The height of the outflow prevention member 4 ′ and the partition member 5 is formed to be higher than the planned thickness of the water stop material 2, and as shown in FIG. The short side (the right side in FIG. 3A) of the formed water-stopping material 2 has a height that is greater than or equal to the planned thickness of the water-stopping material 2. Further, the interval between the partition members 5 is an interval that enables the planned thickness of the water blocking material 2 to be maintained, and is appropriately set according to the inclination of the backfill layer 23. Moreover, the plate | board thickness of the outflow prevention material 4 'and the partition member 5 will not be limited if it can prevent the outflow and the flow-down of the water stop material 2, and should just be set suitably.

  Next, a method for joining the water shielding sheets according to the second embodiment will be described.

  The joining method of the water shielding sheet which concerns on 2nd Embodiment is (1) Foam sheet adhesion | attachment process, (2) Water shielding sheet laying process, (3) Formwork process, (4) Water stop material arrangement | positioning And a process.

(1) Foam sheet adhesion process Since the foam sheet adhesion process is the same as the content shown in 1st Embodiment, detailed description is abbreviate | omitted.

(2) Water-impervious sheet laying step The water-impervious sheet laying step is the same as the contents shown in the first embodiment, and thus detailed description thereof is omitted.

(3) Forming process In the outflow prevention material arranging process, the water blocking material 2 sandwiching the joint a between the water shielding sheets 1 and 1 laid in the sea surface disposal site (underwater) 10 in the water shielding sheet laying process is poured. And a pair of outflow prevention materials 4 ', 4' forming a groove for the purpose, and the outflow prevention materials 4 ', 4' in a direction orthogonal to the outflow prevention materials 4 ', 4' so as to divide the groove at a predetermined interval Is a step of arranging the partition members 5, 5,... (See FIGS. 3A and 3B). That is, a frame for pouring the waterstop material 2 is formed by the pair of outflow prevention materials 4 ′, 4 ′ and the partition members 5, 5,...

(4) Water-stopping material arranging step The water-stopping material arranging step is performed at 110 to 190 ° C. on the mold (outflow preventing materials 4 ′, 4 ′, partition members 5, 5,...) Formed in the outflow preventing material arranging step. This is a step of pouring a water-stopping material (asphalt mastic) 2 that is heated and fluidized (see FIG. 2). When the water blocking material 4 is poured, the independent foamed sheet 3 bonded to the end portion of the water shielding sheet 1 comes into contact with the water blocking material 2, so that the contact surface is melted. Thereby, a discontinuous uneven surface is formed on the contact surface of the independent foam sheet 3 with the waterstop material 2. And since the water stop material 2 and the independent foam sheet 3 mesh when the water stop material 2 enters into the recesses of the discontinuous uneven surface of the independent foam sheet 3, the water stop material 2 and the independent foam sheet 3 are Glue physically. Thereby, the water-impervious sheet 1 and the water stop material 2 are bonded together.
In addition, you may remove outflow prevention material 4 ', 4' after hardening of the water stop material 2. FIG.

  As mentioned above, according to joining structure S2 by 2nd Embodiment, since the water stop material 2 poured into the junction part a on a slope is prevented from flowing down by the partition member 5, it is the same as that of a flat part. The water shielding sheets 1 and 1 can be joined.

Further, since the partition member 5 is in close contact with the poured water-stopping material 2, no gap is formed between the water-stopping material 2 and the partition member 5, and a desired water shielding property can be maintained. It becomes possible.
Moreover, since the outflow prevention member 4 ′ and the partition member 5 are joined to form a mold, the outflow prevention member 4 ′ and the partition member 5 are resistant to deformation without being caused by the pressure of the poured water-stopping material 2. Therefore, it is possible to reduce the material cost.

  Since the function and effect of the water shielding sheet joining method and the water shielding sheet joining structure S2 according to the other second embodiment are the same as the contents shown in the first embodiment, detailed description thereof is omitted. To do.

<Third Embodiment>
In the third embodiment, as shown in FIG. 1, the water shielding layer 11 is formed by laying the water shielding sheet 1 so as to cover the water bottom in a predetermined range surrounded by the caisson revetment 20 or the like, The case where the sea surface disposal site 10 is formed will be described.

  Since the sea surface disposal site 10 according to the third embodiment and the caisson revetment 20 for forming the sea surface disposal site 10 are the same as those described in the first embodiment, detailed description thereof is omitted.

  As shown in FIG. 4, the joining structure S <b> 3 according to the third embodiment includes the water-impervious sheets 1 and 1 arranged side by side and the end of the other water-impervious sheet 1 on the water-impervious sheet 1 and 1 side. In addition, the heat-weldable independent foamed sheets 3 and 3 that are bonded in advance to each other, and the water-adhesive sheets 1 and 1 that are adjacent to each other are disposed so as to straddle the joint portion a and cover the independent foamed sheet 3. It is comprised from the water stop material 2 'arrange | positioned in this way.

  The water-impervious sheet 1 prevents the outflow of contaminants and the like from the sea surface disposal site 10 to the outside. As shown in FIG. 1 and FIG. 4, a plurality of sheets are arranged in parallel to form the joining structure S (S3). The water shielding layer 11 is formed by joining together. In addition, since the water shielding sheet 1 used by joining structure S3 which concerns on 3rd Embodiment is the same as that of what was demonstrated in 1st Embodiment, detailed description is abbreviate | omitted.

  The water blocking material 2 ′ shields the joint portion a for the purpose of preventing the outflow of contaminants and the like from the gap between the joint portions a of the water shielding sheets 1, 1 arranged side by side. As shown in FIG. 4, the water blocking material 2 ′ is in close contact with the water shielding sheet 1 to shield the joint portion a. In addition, the water stop material 2 ′ used in the joining structure S3 according to the third embodiment is a block member made of asphalt mastic that has been cured in advance with the electric heater 2a embedded therein as a heating means. After being placed in a predetermined position, the electric heater 2a is softened by being energized and overheated, thereby being in close contact with the water shielding sheet 1. In the third embodiment, the electric heater 2a is used as the heating means for the water-stopping material 2 '. However, the heating heater 2a is not limited to this. What is necessary is just to select and use from means.

  The independent foamed sheet 3 is an end portion of the water shielding sheet 1 for the purpose of integrally bonding the water shielding sheet 1 and the water blocking material 2 ′, as shown in FIG. Is melted by the heat at the time of close contact with the water shielding sheet 1 of the water blocking material 2 ′ (when heated by the electric heater 2a) and physically bonded to the water blocking material 2 ′. is there. In addition, since the independent foam sheet 3 used by joining structure S3 which concerns on 3rd Embodiment uses the thing similar to what was demonstrated in 1st Embodiment, detailed description is abbreviate | omitted.

  Next, a method for joining the water shielding sheets according to the third embodiment will be described.

  The joining method of the water shielding sheet which concerns on 3rd Embodiment is comprised from the (1) foam sheet adhesion | attachment process, (2) water shielding sheet laying process, and (3) water-stop material arrangement | positioning process. .

(1) Foam sheet adhesion process Since the foam sheet adhesion process is the same as the content shown in 1st Embodiment, detailed description is abbreviate | omitted.

(2) Water-impervious sheet laying step The water-impervious sheet laying step is the same as the contents shown in the first embodiment, and thus detailed description thereof is omitted.

(3) Water-stopping material arrangement process The water-stopping material arrangement process is performed on the upper surface of the independent foamed sheet 3 that is bonded to the end of each water-blocking sheet 1 and straddles the joint a of the water-blocking sheets 1 and 1. A block-shaped water-stopping material 2 ′, which is a hardened asphalt mastic, in which the electric heater 2a is embedded, is disposed. And if the water stop material 2 'is arrange | positioned, it will energize and heat an electric heat 2a, softening an asphalt mastic and making it closely_contact | adhere to the water shielding sheets 1 and 1. FIG. At this time, the contact surface of the independent foamed sheet 3 that is in contact with the waterstop material 2 ′ is melted by the heat of the softened asphalt mastic. Thereby, a discontinuous uneven surface is formed on the contact surface of the independent foamed sheet 3 with the water blocking material 2 ′. And since the water stop material 2 'and the independent foam sheet 3 mesh with each other when the water stop material 2' enters into the recesses of the discontinuous uneven surface of the independent foam sheet 3, the water stop material 2 'and the independent foam sheet 3 are physically bonded. Thereby, the water-impervious sheet 1 and the water stop material 2 ′ are bonded.

  As described above, according to the water shielding sheet joining method and the water shielding sheet joining structure S3 according to the third embodiment, the water blocking material 2 ′ formed in a block shape in advance is disposed, and then overheated to prevent water shielding. Since the sheet 1 (independent foam sheet 3) is bonded, the water stop material 2 'does not flow down even at the joint a on the slope, and the installation location is not limited.

  Moreover, since it is not necessary to arrange a member (outflow prevention member 4) for the purpose of preventing outflow of the water blocking material 2 ', the workability is excellent.

  The effects of the water shielding sheet joining method and the water shielding sheet joining structure S3 according to the other third embodiment are the same as the contents shown in the first embodiment or the second embodiment. Therefore, detailed description is omitted.

<Fourth embodiment>
In the fourth embodiment, in the water shielding sheet joining method according to each of the above embodiments, before the water shielding sheet 1 is laid in water, the granular material made of the asphalt mixture is heated in a closed state in a heated state. A case where a granular ascon bonding process for bonding to the upper surface of the sheet 3 is included will be described (see FIG. 5).

That is, the method for joining the water shielding sheets according to the fourth embodiment includes (1) a foam sheet bonding step, (2) a granular ascon bonding step, (3) a water shielding sheet laying step, and (4) a stop. And a water material arranging step.
The (2) granular ascon bonding step may be performed before the (1) foam sheet bonding step and before the independent foam sheet 3 is bonded to the water shielding sheet 1.

The independent foamed sheet 3 according to the fourth embodiment has a granular ascon 3a, which is a granular material made of an asphalt mixture, as shown in FIG. It adheres to the water-impervious sheet 1 in a state protruding from the upper surface of the sheet.
Here, the mixing | blending of the granular ascon 3a is not limited, What is necessary is just to set suitably.

(1) Foam sheet adhesion process Since the foam sheet adhesion process is the same as the content shown in 1st Embodiment, detailed description is abbreviate | omitted.

(2) Granular Ascon Adhesion Process The granular ascon adhesion process is performed by spreading and rolling the heated granular ascon 3a on the upper surface of the independent foamed sheet 3. The installation surface of the closed foam sheet 3 with the granular ascon 3a is melted by the heat of the heated granular ascon 3a, and further the granular ascon 3a is rolled, so the granular ascon 3a is embedded in the closed foam sheet 3 and shown in FIG. Thus, the independent foam sheet 3 and the granular ascon 3a are physically bonded.

(3) Water-impervious sheet laying step The water-impervious sheet laying step is the same as the content shown in the first embodiment, and thus detailed description thereof is omitted.

(4) Water-stopping material arrangement process Since the water-stopping material arrangement process is the same as the contents shown in the first to third embodiments, detailed description thereof is omitted.
In addition, in the joining method of the water shielding sheet | seat which concerns on 4th Embodiment, it cannot be overemphasized that an outflow prevention material and a partition member are arrange | positioned as needed according to the condition of a base | substrate, and the water stop material to be used.

  As mentioned above, according to the joining method of the waterproof sheet concerning a 4th embodiment, in the waterproofing material arrangement process, it adheres to the independent foamed sheet 3 beforehand with the heat of the waterproofing material 2 which consists of heated asphalt mastic. The granular ascon 3a is melted and bonded to the water stop material 2 integrally. For this reason, the water blocking material 2 is firmly bonded to the water shielding sheet 1 by bonding with the granular ascon 3a and physical bonding with the independent foamed sheet 3. Therefore, the joining structure S of the water shielding sheet excellent in water shielding is formed.

  Further, even when the water shielding sheet 1 is laid, the weight of the granular ascon 3a adhered to the independent foamed sheet 3 enables the water shielding sheet 1 to be laid without being affected by underwater waves. Excellent workability.

  The effects of the water shielding sheet joining method and the water shielding sheet joining structure S3 according to the other fourth embodiment are the same as the contents shown in the first to third embodiments. Therefore, detailed description is omitted.

  Next, the result of having conducted the demonstration experiment about the joinability of the joining structure comprised by the joining method of the water shielding sheet of this invention is shown.

  In this demonstration experiment, as the independent foamed sheet 3, a foaming ratio in the air of 15 times, a softening point of 122 ° C., and a thickness of 5 mm is used. And the granular ascon 3a is previously adhere | attached on the upper surface of the independent foam sheet 3 (refer FIG. 5). As the water shielding sheet 1, a rubber sheet (EPDM) is used. As the outflow prevention material 4, asphalt mastic blended with 20% by mass of asphalt, 30% by mass of stone powder, and 50% by mass of sand is formed into a prism having a cross section of 5 cm × 5 cm. Further, as the waterstop material 2, a mixture of 20% by mass of asphalt, 30% by mass of stone powder and 50% by mass of sand heated to 170 ° C. and kneaded is used.

  In this demonstration experiment, the two water-impervious sheets 1 and 1 to which the independent foamed sheets 3 are respectively bonded are laid in a water tank (not shown) in which water is stored, After arranging the pair of outflow prevention materials 4 and 4 with the independent foamed sheets 3 and 3 sandwiched therebetween, the water stop material 2 is poured between the outflow prevention materials 4 and 4 to form the joining structure S (FIG. 2). reference).

  Next, after the asphalt mastic is cooled and solidified, a specimen having dimensions of 9 cm in width, 30 cm in length, and 5 cm in thickness is cut out from the formed joint structure S. At this time, the joint part a between the water shielding sheets 1 is cut out so as to be approximately in the center in the length direction.

Subsequently, the specimen was set in a pressurized water permeability tester and pressurized at 20 ° C. and a pressure of 0.5 MPa for 10 days to conduct a water permeability test on the joint. The water permeability test results are shown in Table 1.
In addition, an iron plate having a width of 9 cm, a length of 20 cm, and a thickness of 1 cm was adhered to the back of the specimen with an epoxy resin, and the sheet was tested using an Instron testing machine at a test temperature of 20 ° C. and a tensile speed of 0.5 cm / min. A tensile shear test of the joint was performed. Table 1 shows the results of the tensile shear test.

  As shown in Table 1, the water imperviousness of the sheet joint was ensured, the tensile shear strength was 90 kPa or more, and the result of the water impervious sheet being mechanically joined was obtained.

The preferred embodiments according to the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the spirit of the present invention.
For example, in each of the above embodiments, the water shielding sheet joining method and the water shielding sheet joining structure according to the present invention are applied when forming the water shielding layer of the sea surface disposal site. The application location of the water shielding sheet joining method and the water shielding sheet joining structure is not limited to the sea surface disposal site, and can be applied to, for example, repair of a reservoir or a reservoir.

  Further, in the fourth embodiment, the granular material made of asphalt mixture is adhered to the upper surface of the independent foam sheet before the impermeable sheet is laid in water, but the impermeable sheet is laid in water. Before heating, an asphalt mixture in a heated state may be laid on the upper surface of the closed foam sheet to form an ascon layer having a predetermined thickness (for example, 5 cm). In this way, if an ascon layer having a predetermined thickness physically bonded to the independent foam sheet is formed in the air in advance, the water stopping material and the ascon layer are integrated in the water stopping material arranging step. Further, it is possible to form a bonded structure of a water shielding sheet excellent in water shielding.

It is a perspective view which shows the outline of the sea level disposal site which concerns on 1st Embodiment thru | or 3rd Embodiment. It is a cross-sectional view which shows the joining structure of the impermeable sheet which concerns on 1st Embodiment. It is a figure which shows the joining structure of the impermeable sheet concerning 2nd Embodiment, Comprising: (a) is a longitudinal cross-sectional view, (b) is a cross-sectional view. It is a cross-sectional view which shows the joining structure of the water shielding sheet which concerns on 3rd Embodiment. It is a cross-sectional view which shows a part of joining structure of the impermeable sheet which concerns on 4th Embodiment.

Explanation of symbols

1 Water-blocking sheet 2, 2 'Water-stopping material 2a Electric heater (heating means)
3 Independent foam sheet (foam sheet)
3a Granular ascon (granular material consisting of asphalt mixture)
4,4 'Outflow prevention material 5 Partition member 10 Sea surface disposal site 11 Water shielding layer 20 Caisson revetment G Base S, S1, S2, S3 Joining structure (joining structure of water shielding sheet)
a Joint

Claims (9)

Adhering a heat-weldable foam sheet to the end of the water-impervious sheet;
Laying a plurality of the water shielding sheets in water;
A step of closely adhering a water-stopping material to an end portion of the water-blocking sheet to which the foamed sheet is bonded, in a state of straddling a joint portion between the water-blocking sheets adjacent to each other;
A method for joining a water shielding sheet including
The water-stopping material is a material that can be molded into an arbitrary shape at room temperature and has a performance of melting by heating, and the water-stopping material is in close contact with the end of the water-blocking sheet in a molten state. A method for joining a water shielding sheet, which is characterized.   The method for joining waterproof sheets according to claim 1, wherein the waterproof material is made of asphalt mastic, and the waterproof material is brought into close contact with an end portion of the waterproof sheet by pouring.   The method for joining a water shielding sheet according to claim 2, further comprising a step of forming a groove for pouring the water-stopping material by arranging a pair of outflow prevention members with the joint portion interposed therebetween.   The method for joining waterproof sheets according to claim 3, wherein the outflow prevention member is a cured body of asphalt mastic.   5. The water shielding sheet joining method according to claim 3, wherein the partition member is arranged so that the groove is divided at a predetermined interval.   The water stop material is made of a block material made of asphalt mastic cured with heating means embedded therein, and after placing the block material at a predetermined location, it is heated to the end of the water shielding sheet. The water shielding sheet joining method according to claim 1, wherein a water blocking material is adhered.   The process according to claim 1, further comprising a step of adhering a granular material made of an asphalt mixture to the upper surface of the foamed sheet in a heated state before the water shielding sheet is laid in water. The water shielding sheet joining method according to any one of the preceding claims. Two water-impervious sheets arranged side by side;
A heat-weldable foam sheet that is bonded in advance to the other water-impervious sheet side end of the water-impervious sheet, and
A waterproofing material closely adhered to the two water-impervious sheets in a state of straddling the joint between the two water-impervious sheets, and bonded to the foam sheet;
A structure for joining water-impervious sheets, comprising:   The bonded structure of the water shielding sheet according to claim 8, wherein a cured body of asphalt mastic is disposed so as to sandwich the water blocking material from both ends.

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