JPS5941504A - Water-proofing work for joint of rubberized asphalt sheet - Google Patents

Abstract

PURPOSE:To increase the water-tightness of the joints of water-proof sheets by making the joints even by a method in which the end portions of rubberized asphalt sheets formed by laminating a base material with an adhesive layer are laminated and a hot molten asphalt is coated on said portion. CONSTITUTION:A rubberized asphalt sheet is formed by laminating an adhesive layer 3 on a base material 2. composed of a mixture of a rubber of butadiene, etc., and 50% or more a bituminous substance, e.g., blown asphalt, etc. The adhesive layer 3 is of basically the same composition as the base material 2 but richer in the bituminous substance than in the base material 2. The end portions of the sheets 1 are laminated, and a hot molten asphalt 5 is coated on said portion 4 in such a way that the adhesive layer 3 in the laminated portion 4 is softened and bonded with the base material 2 of the lower sheet 1. Afterwards, the molten asphalt 5 is allowed to cool for solidification to increase the water- tightness of the joint.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a joint waterproofing method for rubberized asphalt sheets for waterproofing purposes such as roofs, water tanks, etc.

The rubberized asphalt sheet mentioned above is made of a mixture of rubber and asphalt, and has appropriate elasticity as well as excellent durability and weather resistance, so it is widely used in various waterproofing constructions.

Conventionally, the joint waterproofing method for rubberized asphalt sheets involves applying a solvent-based adhesive to the joints at the edge of the sheet, and after the solvent evaporates, overlapping and tightening other sheets. A construction method has been adopted in which parts are overlapped and then heated with a burner to join them. However, the former construction method requires a certain amount of adhesive, an open time, an appropriate amount of crimping, etc. There are constraints, and these conditions are greatly influenced by the environmental conditions at the time of construction. For example, in strong winds, adhesion may occur due to the adhesion of sand and dust; in high temperatures, the open time is short, resulting in adhesion defects due to over-drying; and in low temperatures, the open time becomes longer, reducing construction efficiency. During installation, environmental conditions had to be fully understood, as condensation water that forms on the adhesive surface at high temperatures can cause poor adhesion of the sheet. Furthermore, from a technical standpoint, there were many causes of adhesion failure, such as variations in adhesive strength due to uneven coating and poor adhesion due to insufficient rolling pressure.

On the other hand, even with the latter construction method, uneven welding tends to occur due to variations in the sheet surface temperature depending on the heating position, and poor adhesion tends to occur due to deterioration of the sorting material due to heating at high temperatures.

As described above, the construction methods that have been widely adopted in the past are greatly influenced by the skill level of the worker as well as the environmental conditions, and in each case, high expectations were placed on the skill level of the worker.

This invention aims to improve the shortcomings of these conventional joint construction methods in many ways, and it is possible to make the joints of each tarpaulin sheet uniform without requiring special skill on the part of workers, and to achieve a high level of accuracy and high efficiency. This is a common practice, and its gist is that hot molten asphalt is applied to the overlapped or abutted parts of rubberized asphalt sheets with adhesive layers, and the heat retained in this molten asphalt is actively utilized. , the point is to perform efficient jointing of each tarpaulin sheet.

Next, specific embodiments of the joint waterproofing method of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a partial longitudinal cross-sectional view of an example of a rubberized asphalt sheet used in the present invention. It is laminated and its thickness is about 2 to 4 m/m. The base material (2+) constituting the sheet (1) contains bituminous materials such as blown asphalt, straight asphalt, etc. of 50 inches or more! A mixture, if necessary, a thermoplastic synthetic resin, such as a styrene butadiene block copolymer,
It is also possible to strengthen the base material by adding polyethylene, polypropylene, polybutadiene, etc.

In addition, the adhesive layer (3) is basically composed of the same composition as the base material (2), and in order to increase the adhesiveness, the amount of bitumen added to the base material (2) is set to be higher than that of the base material (2). 1; Intentionally increased in amount, with a softening point of 80° to 120°
'C, penetration index is 5 or more (JIS K 25.30
), the hot-melting asphalt softens due to the heat it possesses as shown below, and the bonding with the other side sheet base material becomes easier and stronger.

Rubberized asphalt sheet (1) consisting of the above structure (
1) is lap-jointed at its edges as illustrated in Figure 2, but first the side edges of the sheets are overlapped, and then hot molten asphalt (5) is applied to this overlapped part (4). ). Hot molten asphalt (5
) The adhesive layer (3) of the overlapping part (4) is appropriately softened by the heat retained in the layer (4) and bonded to the base material (2) of the lower 7-t (1), and at the same time the hot melt asphalt (5) is released. Good for cold solidification,
The watertightness of the core area further increases due to the accumulation and solidification at the sheet joint.

Further, in another embodiment of the present invention illustrated in FIG. (7) is laminated, and then hot melt asphalt (5) is applied on the auxiliary sheet (7), and the heat of the hot melt asphalt is used to form the auxiliary sheet) [Adhesive layer (3) of 71]
The auxiliary sheet (7) and the laid rubberized asphalt sheets (1) (1) are joined together, and at the same time, the hot molten asphalt is allowed to cool and solidify, and is piled up at the joint part of the butt sheet. The solidification further enhances the watertightness of the sheet abutting portion.

Hot-melted asphalt used in this construction method (5) A wide range of materials commonly referred to as asphalt, such as Haflon asphalt, straight asphalt, asphalt compound for waterproofing work, and natural asphalt, can be used, and the temperature at which the molten asphalt is applied is 160~280°
C, preferably 200 to 260°C. If you apply asphalt to the notebook joint at this melting temperature, it will be difficult to apply it.
It is a rubberized asphalt sheet of about 4 m/m.
If □, the heat retained by the hot-molten asphalt is sufficient to soften the adhesive layer of the sheet.

The joint construction method for waterproof sheets of this invention involves overlapping rubberized asphalt sheets having an adhesive layer, or by butting the sheets together and overlaying an auxiliary sort made of the same material on the abutted part, and then overlapping the sheets at the joined part. The adhesive layer of the rubberized asphalt sheet is softened and fused using the retained heat of the molten asphalt, making it possible to firmly join the joints of the sheet, making it easier to work than conventional adhesive construction methods or burner construction methods. It is less dependent on the skill level of the person involved, and is not affected by the environmental conditions at the time of construction, making it possible to obtain uniform joints of the tarpaulin sheet with a high degree of perfection, and it is also possible to Compared to the construction method, the temperature distribution at the sheet joint is more uniform, and unlike conventional adhesive construction methods, there is no uneven adhesive application, so there is no uneven adhesion, and the hot-melt asphalt that is then applied is left to cool and solidify. Then, the presence of the solidified asphalt layer increases the watertightness of the joint portion of the tarpaulin sheet, making the waterproofness even more complete.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a part of the rubberized asphalt sheet used in this invention, FIG. 2 is a cross-sectional view of the joint portion when the joint waterproofing method of the rubberized asphalt sheet according to the present invention is implemented, and FIG. 2 is a diagram corresponding to FIG. 2 showing another embodiment. In the figure, (1) is a rubberized asphalt sheet, (2) is a base material, (3) is an adhesive layer, (4) is a superimposed part, (5) is a hot melt asphalt, (6) is a butted part, (7) indicates an auxiliary sheet. Patent applicant Mitsuboshi Belting Co., Ltd.

Claims (1)

[Claims] 1. To join the edges of rubberized asphalt sheets having adhesive layers, hot-melt asphalt is applied to the rubberized asphalt sheets located at the joint, and the adhesive layer of the sheets is bonded by the heat retained in the applied asphalt. A joint waterproofing construction method for rubberized asphalt sheets, characterized by softening and joining the edges of rubberized asphalt sheets.