JP5323980B1 - Waterproof structure of road bridge deck - Google Patents

Abstract

[Problem] To provide a waterproof layer having high performance for preventing salt damage, frost damage, rust corrosion, and other damage deterioration provided on a floor slab surface of a road bridge for paving asphalt pavement.
SOLUTION: A liquid curable resin is applied to a road slab surface such as a concrete slab or a steel slab, and dredged sand coated with petroleum asphalt is sprayed on the coated surface to cure the curable resin. A waterproof structure for road bridge slabs, wherein a waterproofing asphalt coating waterproofing material is adhered thereto, followed by asphalt pavement.
[Selection figure] None

Description

  TECHNICAL FIELD The present invention relates to a method for forming a waterproof layer on a concrete plate surface and a steel plate surface of a floor slab surface of a road bridge for paving asphalt pavement, and has a high performance for preventing salt damage, frost damage, rust corrosion and other damage deterioration. Is to provide.

  In civil engineering and architectural work, waterproofing is an important part of the work. Civil engineering or building structures with imperfect waterproofing not only significantly shorten the durability of the structure, but also may result in loss of assets installed in the structure. That is important.

  In concrete bridges, asphalt pavement is made on concrete floor slabs. Rainwater that enters from the damaged part of the asphalt pavement or the edge of the floor slab is caused by cracks on the concrete slab surface. If it penetrates into the concrete and reaches the rebar inside the concrete, it will corrode the rebar and also affect the life of the concrete bridge itself. Therefore, before paving the asphalt pavement, a waterproof layer is applied to the concrete slab surface. We are constructing. Moreover, construction of drainage pavement is increasing for improving vehicle running safety and reducing noise. In drainage pavement, rainwater penetrates into the pavement, and the role of this waterproof layer is further increasing.

  Floor slabs are under more severe conditions than ever due to the increase in traffic volume and vehicle size in recent years, but replacement and repair of floor slabs require a large amount of money, and traffic restrictions and road closures associated with construction work The impact of traffic congestion on society is great. Under such circumstances, in order to improve the durability of the concrete slab, the performance of the waterproof layer is required to be higher.

  Conventionally, as this waterproof layer, there are a sheet-type waterproof layer, a coating-type waterproof layer, and a pavement-type waterproof layer. As the sheet waterproof layer, there is an asphalt waterproof sheet formed by impregnating a special asphalt into a synthetic fiber nonwoven fabric or glass fiber (Patent Document 1). There are a method in which such a sheet is attached to the floor slab surface with heated asphalt, or attached to the floor slab surface while heating the surface of the sheet with a construction machine.

The coating waterproof layer is a type in which rubber-modified asphalt is heated and melted to form a coating film, and a material in which a synthetic rubber such as chloroprene is dissolved in a volatile solvent is applied and dried to form a coating film. There are various types, for example, a type in which a two-component reaction type epoxy resin is cured to form a coating film, and a type in which a polyurethane resin is cured to form a coating film in recent years (Patent Document 2).
The pavement waterproofing layer is a pavement asphalt mixture made by adding aggregate and stone powder to special asphalt using a normal pavement machine.

In order to incorporate the latest knowledge on materials and technologies used for waterproofing layers in 2007, the “Road Bridge Reinforced Concrete Floor Waterproofing Layer Design and Construction Material” [Japan Road Association] A full review was also carried out. At the same time, each related organization such as NEXCO will revise the standards significantly, and at the same time, establish all waterproof mechanisms that protect the floor slabs, such as floor slabs, pavements, waterproof layers, and drainage facilities, from water. The situation is focusing on.
From such a background, the actual situation is that an excellent waterproof layer capable of exhibiting the performance of the entire system is desired.

  Furthermore, in cold snowy regions such as Hokkaido and Honshu in the Sea of Japan, repeated effects of freeze / thaw and the effects of salt damage caused by antifreezing agents are greatly added, and further improvements are required for this floor slab waterproofing system.

JP 2000-26558 A Japanese Patent No. 3128721

The present invention relates to a floor slab waterproofing system that requires this further improvement.
The following issues are required for the waterproof layer to improve the durability of road bridge decks and to cope with the repeated effects of freezing and thawing in cold snowy areas and the effects of salt damage caused by antifreezing agents.
Tensile and shear adhesion,
Crack resistance,
Blistering resistance performance,
Adaptability to asphalt pavement load,
chemical resistance,
Adaptability to temperature changes,
Resistance to repeated loading of wheel loads in service,
Etc.

Of the above, the tensile adhesiveness and shear adhesiveness must have no effect on the adhesiveness between the floor slab and the pavement due to the presence or absence of the waterproof layer. It is verified by the property and shear adhesiveness.
Crack resistance means that even if a slight crack occurs due to the heavy traffic wheel load that the floor slab receives after service, it will continue to have resistance to repeated opening and closing of the crack.
Blistering prevention performance refers to the occurrence of blistering due to the influence of moisture on the concrete floor slab and direct sunlight during the summer days, etc., when there is a standing period between installation of the waterproof layer and paving. This is the performance to prevent this.

Adaptability to asphalt pavement load means that the waterproof layer is expected to be damaged by pavement heat and the indentation load of the aggregate in the asphalt mixture during asphalt rolling, so resistance to this is necessary And
Since chemical resistance has an alkali as a chemical substance that affects the waterproof layer, resistance with calcium hydroxide is required.
The adaptability to the temperature change takes into consideration the influence of the area and the weather during the service period, and particularly in a cold area, a performance that can withstand a temperature change of −30 ° C. to 50 ° C. (temperature difference 80 ° C.) is required. The resistance of a wheel load in service to repeated load assumes fatigue due to repeated running of a large truck in service, and this is verified by a test called a normal wheel tracking test.

  As described above, the present invention provides a waterproof structure for road bridge slabs that can cope with the problems of conventional waterproofing layers and the effects of repeated freeze-thawing in snowy cold regions and the effects of salt damage caused by antifreezing agents. It is intended.

In order to solve the above-described problems, the present inventors have developed the following floor slab waterproofing system as a result of intensive studies.
The waterproof structure of the road bridge deck according to the present invention is such that a liquid curable resin is applied to a road bridge deck such as a concrete deck or a steel deck, and dredged sand coated with petroleum asphalt on the coated surface is evenly dispersed. Then, the curable resin is cured to fix the dredged sand to the coating surface, and further, a heating type asphalt coating waterproof material is applied thereon, and an asphalt pavement is applied on the heating type asphalt coating waterproof material. It is characterized by.

The present invention relates to a hardened resin layer, a dredged sand layer coated with petroleum asphalt held in the hardenable resin layer, a heating asphalt coating waterproofing material on a road bridge deck such as a concrete floor slab and a steel floor slab. A waterproof layer formed by sequentially laminating a layer and an asphalt pavement layer is formed. By adopting this structure, various problems that have been considered as a conventional problem in addition to waterproof performance can be solved.
In other words, the waterproof system of the present invention is suitable for floor slabs and pavement adhesiveness, chemical resistance, crack resistance, adaptability to asphalt pavement load, adaptability to temperature changes, resistance to repeated load of wheel load, etc. In addition to satisfying the basic performance as a plate waterproof layer, it is possible to provide a waterproof system with high performance against blistering resistance performance and the effects of repeated freezing and thawing in snowy cold regions and the effects of salt damage caused by antifreezing agents.

  The floor slab to which the waterproof structure of the present invention is applied is not particularly limited, and may be a conventional concrete slab, a steel slab or the like. Depending on the material of the floor slab, the plate surface may be cleaned or surface polished. Depending on the curable resin used, it is better to remove dust and moisture from the printing plate.

As the curable resin to be applied to the printing plate, a liquid curable resin is used, and a reactive curable resin is preferable for a strong adhesive force and a certain waterproof property. The reaction curable resin may be either a room temperature curable resin or a heat curable resin, and may be a one-component type or a two-component type composed of a main agent and a curing agent.
The curable resin may be any of urethane, epoxy, and acrylic resins. For example, normal temperature containing (meth) acryl oligomers such as (meth) acrylic acid ester, urethane (meth) acrylate, and epoxy (meth) acrylate. Examples thereof include a curable (meth) acrylic resin. However, it is not limited to these.
When the reactive curable resin has a low viscosity, for example, when applied to a concrete plate, it partially impregnates the concrete surface and forms a layer that blocks water vapor on the plate surface, thereby preventing blistering. be able to.
Although the application amount of the curable resin is not particularly limited, it is set to such an extent that the dredged sand dispersed on the application surface is fixed and held. The coating amount of the acrylic curable resin as one example, 0.2 kg / m ² from 0.5 kg / m ² is desirable. If it is less than 0.2 kg / m ² , the surface cannot be uniformly covered, and it becomes difficult to suppress blistering.

The reaction curable resin is generally applied by a method such as roller brush application, brush application, flow application using a registration mark, or spray application using airless spray, but is not limited to these methods.
The number of times of application is not particularly limited. In the present invention, when the top application is performed, the asphalt-coated silica sand (hereinafter referred to as AS silica sand) is coated before the reaction-curable resin is cured. Although it spread | spreads on a surface, it makes it the state which spread | dispersed AS cinnabar is fixed after hardening of a coating film. Since AS cinnabar is asphalt-coated, it will be sufficient to apply a heated asphalt coating waterproofing material applied to the upper surface.
In addition, you may use AS cinnabar instead of the cinnabar used in the case of the asphalt pavement paved on the upper surface of the waterproof layer of this invention.

As the cinnabar used for AS cinnabar to be spread on the coated surface, those with an average particle size of 0.5 mm to 2.5 mm can be used. Ordinary cinnabar 3 (particle diameter 1.2 mm to 2.4 mm) or cinnabar 4 (particle diameter 0.6) mm to 1.2 mm). AS cinna sand improves tensile adhesion and shear adhesion between the curable resin and the heat-resistant asphalt coating waterproofing material applied on it. If the particle size is too small, these adhesive strengths decrease. In addition, if the particle size is too large, a portion that is not taken into the thickness of the waterproof layer is generated, which may impair the waterproof property of the entire waterproof layer. Therefore, an appropriate particle size is required. On the other hand, there is no problem whether the material of the cinnabar used as the AS cinnabar is natural or artificial.
As for the amount of AS cinnabar, 0.2 kg / m ² to 0.4 kg / m ² is suitable when using cinnabar No.4.

AS cinnabar is a petroleum asphalt that is pre-coated on cinnabar, using a mixture of bronze asphalt, stray, and asphalt. This mixed asphalt is heated and melted. As a result, asphalt-coated cinnabar is obtained.
As an example of petroleum asphalt for AS dredged sand, a mixture of 10-20 blown asphalt and 60-80 straight asphalt can be exemplified, and these can be mixed in equal amounts, or in any proportion depending on the desired waterproofness, etc. Mix and use.

AS asphalt coating waterproofing material to be applied on the surface sprayed with AS cinnabar, it conforms to the grade I standard of flooring waterproofing material described in East Japan / Central Japan / West Japan Expressway Co., Ltd. It shall be a suitable waterproof material. As mentioned above, the waterproof layer is required to have various performances, but the grade I standards for floor slab waterproofing materials described in the East Japan / Central Japan / West Japan Expressway Co., Ltd./Structure Construction Management Guidelines (NEXCO standard) As long as the waterproof material matches the above, a comprehensive waterproof performance can be secured. The heating type asphalt waterproof membrane is preferably in the range of 1.2 kg / m ² to 1.6 kg / m ² . 1.4 kg / m ² is desirable.
A normal asphalt mixture used for paving roads and the like is paved on the heat-resistant asphalt coating waterproof material to complete the waterproof system of the present invention.

Table 1 (quality standards for waterproofing materials) and Table 2 (quality standards for waterproofing layers) show the grade I standards of the construction work management procedures (NEXCO standards) for floor slab waterproofing materials.

Hereinafter, details of the present invention will be described in Examples.
Example In this example, an acrylic resin was used as the reaction curable resin.
A concrete floor slab was used as a floor slab specimen, the surface was polished in advance, a uniform surface was removed to remove dust, and the moisture was dried. On top of this, 0.4 kg / m ^{2 was} applied as a primer with an acrylic resin (a resin liquid comprising a resin mainly composed of an acrylic monomer and a curing agent (such as an organic peroxide)). Immediately thereafter, AS cinnabar was sprayed on the primer-primer application surface in an amount of 0.3 kg / m ² .
AS cinnabar is mixed with 10-20 blown asphalt and 60-80 straight asphalt in an equivalent amount of cinnabar (heated sol No. 4) heated at a temperature of 140 ° C. The one coated with asphalt was used.

After standing for 1 hour or longer, after confirming that AS cinnabar sand had adhered to the primer coating surface, a rubber asphalt-based coating waterproof material was applied as a heating asphalt coating waterproof material. This waterproofing coating material is a waterproofing material that conforms to “Grade I of floor slab waterproofing material” described in the above construction management guidelines.
After heating and applying the rubber asphalt-based waterproof coating material, immediately spray ordinary sand 4 to cool the coating waterproof material, and the excess sand that did not adhere to the waterproof coating layer Was removed.
Table 3 shows the configuration of the waterproof system according to this example.

The asphalt pavement in the configuration shown in Table 3 above was applied, and the pavement type was 13F (straight asphalt) as the type of pavement, and the pavement temperature was 140 ° C. and the compactor was adjusted to a linear pressure of 30 kg / cm 2.
This pavement is one pavement load in the load test in the waterproof material test described in East Japan / Central Japan / West Japan Expressway Co., Ltd./Structure Construction Management Guidelines.

Test Example Various tests were performed on the concrete floor slab specimens having the above waterproof structure.
1) Water immersion wheel tracking test A water immersion wheel tracking test, which is one of the load tests, was performed on this specimen. The conditions of this test are as shown in Table 4 below.

2) Tensile adhesion test Next, a tensile adhesion test was performed to evaluate the performance of the waterproof layer. This test was performed according to the test method described in Appendix-1 of “Road Bridge Floor Waterproof Guidebook”.
For the test, a core cutter with a diameter of 10 cm was removed from the specimen, and a fixing jig was bonded to the upper and lower surfaces of the extracted core with an epoxy adhesive and allowed to stand for 6 hours or more at room temperature to cure the adhesive. The fixing jig thus constructed was installed in an autograph (tensile tester) and a tensile test was performed. The measurement conditions are as shown in Table 5.

表６に示すとおり、引張接着試験の結果は、東日本・中日本・西日本高速道路株式会社・構造物施工管理要領の規格に適合する。なお、別途その他の要求性能に対しても下記表５に記載のとおり適合するものであることが確認された。 Table 6 shows the results of the tensile adhesion test.

As shown in Table 6, the results of the tensile adhesion test conform to the standards of East Japan / Central Japan / West Japan Expressway Co., Ltd./Structure Construction Management Guidelines. In addition, it was confirmed that other required performances were also adapted as shown in Table 5 below.

3) Tests based on other standards Tests based on the Kanto Civil Engineering Standard (Cold Civil Engineering Laboratory Standard) and the NEXCO standards were conducted.
As the asphalt pavement in the test body according to the above example (configuration shown in Table 3), the test was subjected to dense-graded AS pavement (dense-graded asphalt pavement) and SMA pavement (crushed stone mastic asphalt pavement) (with pavement), The test was conducted on a structure up to a heat-resistant asphalt paint waterproofing material (no pavement) without asphalt pavement.
The results are shown in Table 7. As can be seen from the results in Table 7, both “with paving” and “without paving” passed the test.

  The slabs which are the constituent requirements of the present invention, the slab coated with petroleum asphalt, and the flooring slab which is not laminated in the order shown in the present invention without using the heat-resistant asphalt coating waterproofing material are the above tests. Did not show good results. In particular, lamination without using asphalt-coated cinnabar had low waterproofness and tensile adhesive strength, and peeling from the cinnabar layer was observed.

Claims (7)

  On a road bridge floor such as a concrete slab or a steel slab, a curable resin layer, a dredged sand layer coated with petroleum asphalt held in the curable resin layer, a heated asphalt coating waterproofing material layer, and an asphalt A waterproof structure for road bridge decks, which is formed by laminating paving layers sequentially.   2. The floor slab waterproofing structure according to claim 1, wherein the petroleum asphalt coated on dredged sand is a mixture of bron asphalt and straight asphalt.   The slab waterproofing structure according to claim 1 or 2, wherein the cinnabar is cinnabar having a particle diameter of 0.3 mm to 2.4 mm.   The heating-type asphalt coating waterproofing material is a waterproofing material that conforms to the grade I standard of floor slab waterproofing material described in the construction management guidelines of East Japan / Central Japan / West Japan Expressway Co., Ltd. Item 4. The floor slab waterproofing structure according to any one of Items 1 to 3.   The slab waterproof structure according to any one of claims 1 to 4, wherein the curable resin is any one of a urethane resin, an epoxy resin, and an acrylic resin.   It is characterized by the use of dredged sand coated with petroleum asphalt for bonding between the curable resin coating layer and the heated asphalt coating waterproofing material, and for bonding between the heated asphalt coating waterproofing material and the pavement applied thereon. The floor slab waterproofing structure according to any one of claims 1 to 5.   A liquid curable resin is applied to a floor slab surface such as a concrete slab or a steel slab, and the coated surface is sprayed with silica sand coated with petroleum asphalt, and the curable resin is cured to fix the silica sand. A waterproof construction method for floor slabs, which comprises bonding a heat-resistant asphalt coating waterproof material to an asphalt pavement.