JP6858574B2 - Adhesion-enhanced drainage basin - Google Patents

Description

The present invention is a technique for preventing deterioration of a floor slab or a girder of a bridge, and relates to a technique for improving the adhesive force between a drainage basin used for the floor slab and the floor slab.

In recent years, the amount of antifreeze agent using sodium chloride or calcium chloride has tended to be sprayed on the pavement surface of roads. This is because the use of studded tires has been banned, and it has become necessary to reliably prevent freezing of the pavement surface, and along with this, a large amount of antifreezing agent has been sprayed. However, when an antifreeze agent is used, it becomes necessary to consider the drainage of salty water in the drainage of the pavement surface. Salt corrodes metal and deteriorates concrete. Therefore, a plurality of drainage basins for draining rainwater that has fallen on the bridge are buried in the floor slab of the bridge at predetermined intervals. Water containing salt will also be drained from this drainage basin, but if there is a gap between the drainage basin and the floor slab and water infiltrates, it will accelerate the deterioration of the floor slab. Become. Further, not only the floor slab but also the steel girders and concrete girders that support the floor slab are deteriorated by the water that has entered the inside, which may lead to a decrease in the durability of the entire bridge.

Patent Document 1 discloses a technique relating to a rainwater fall prevention bridge drainage basin. The rainwater fall prevention bridge drainage basin is integrally molded with rubber, and the basin body consists of two parts, an upper part of the basin and a drainage cylinder placed below it. The rainwater fall prevention bridge drainage basin is inserted into the drainage basin mounting hole formed through the floor slab of the bridge, and is appropriately attached by fixing means. A rainwater fall prevention flange is projected over the entire circumference of the outer peripheral surface of the upper part of the box. This rainwater fall prevention flange portion is installed on the waterproof layer, and is arranged in a state of being sandwiched between the waterproof layer and the pavement portion.

Japanese Unexamined Patent Publication No. 2003-301414

However, even with the method of Patent Document 1, a minute gap may be generated at the boundary between the floor slab concrete and the drainage basin, and water containing salt infiltrates the floor slab from this gap, and the bridge such as the floor slab and the bridge girder. There is a risk of progressing overall deterioration. Further, when the drainage basin has a flange as in Patent Document 1, it is considered that a problem occurs in the workability of the drainage basin. This is because the flange portion needs to be arranged so as to be sandwiched between the pavement surface and the waterproof layer, so it is necessary to install a drainage basin before pavement.

Therefore, it is preferable to eliminate the gap between the drainage basin and the floor slab by increasing the adhesive force at the boundary between the outer peripheral surface of the drainage basin and the concrete. It is thought that the performance cannot be achieved as necessary, and it is inevitable that a minute gap will be created between the floor slab and the drainage basin. Inorganic zinc rich paint is applied to the surface of the drainage basin to contribute to strengthening the adhesive force, but even the drainage basin that has been painted in this way does not have high adhesive force to concrete.

On the other hand, when using an FRP resin drainage basin, it is not possible to paint with inorganic zinc rich paint, so concrete is poured as it is, or silica sand is sprayed on the surface instead of such zinc painting to strengthen the adhesive force. There is also. However, the current situation is that the drainage basin sprayed with such silica sand does not have the expected adhesive strength. Therefore, it is desired to improve the adhesive force between the outer peripheral surface of the drainage basin and the concrete.

Therefore, an object of the present invention is to provide a drainage basin capable of improving the adhesive force between the floor slab and the drainage basin and closing the gap between the floor slab and the drainage basin.

In order to achieve the above object, the drainage basin according to one aspect of the present invention has the following features.

(1) The drainage basin provided on the floor slab of a bridge is characterized in that a polymer cement mortar is applied to the outer peripheral surface of the drainage basin.

According to the aspect described in (1) above, the adhesive force between the outer peripheral surface of the drainage basin and the concrete used for the floor slab is enhanced, and it is possible to prevent a gap from being formed between the drainage basin and the floor slab during construction. .. By arranging the drainage basin at the time of construction of the floor slab in a state where the polymer cement mortar is applied to the outer peripheral surface of the drainage basin in advance, it is possible to improve the adhesive force between the drainage basin and the floor slab. As a result, it prevents the formation of a gap between the drainage basin and the floor slab, prevents the ingress of drainage containing antifreezing agents used especially in winter, and deteriorates the concrete, reinforcing bars, girders, etc. used for the floor slab. Can be prevented.

(2) In the drainage basin according to (1), it is preferable that the outer peripheral surface of the drainage basin is provided with a large number of irregularities, and the mortar is coated on the unevenness.

(3) In the drainage basin according to (1), it is preferable to spray silica sand on the outer peripheral surface of the drainage basin and then spray the mortar on the silica sand.

According to the embodiment described in (2) or (3) above, it is possible to increase the adhesive force between the drainage basin and the mortar, so that it is possible to more reliably prevent the formation of a gap between the drainage basin and the floor slab. it can.

(A) It is a top view of the part where the drainage basin is installed of the 1st embodiment. (B) It is sectional drawing from the front of the part where the drainage basin is installed of 1st Embodiment. It is sectional drawing from the side surface of the drainage basin installed in the bridge of 1st Embodiment. It is a perspective view of the drainage basin of 1st Embodiment.

First, the first embodiment of the present invention will be described with reference to the drawings. FIG. 1A shows a top view of a portion where the drainage basin 10 of the first embodiment is installed. FIG. 1B shows a cross-sectional view from the front of the portion of the bridge 100 where the drainage basin 10 is installed. FIG. 2 shows a cross-sectional view from the side surface of the portion of the bridge 100 where the drainage basin 10 is installed. The drainage basin 10 is composed of three parts, a square frame portion 11, a tapered portion 12, and a tubular portion 13. The drainage basin 10 is usually cast of FC250 or the like as a material, and such a drainage basin is rust-proofed using an inorganic zinc rich paint. In addition to this, a drainage basin made of galvanized steel or an FRP drainage basin may be used. In this embodiment, the drainage basin 10 will be described as using a steel material. The square frame portion 11 is a rectangular frame designed to accommodate grating and the like, and a portion connected from the lower portion of the square frame portion 11 to the tubular portion 13 is a tapered portion 12.

The bridge 100 has a floor slab 50 and a wall balustrade 30, and drainage basins 10 are provided near the ground covering portion 31 provided in the lower part of the wall balustrade 30, that is, on both sides of the bridge 100 at predetermined intervals. The interval at which the drainage basin 10 is installed is determined with reference to the amount of rainfall and the wastewater treatment capacity for the bridge section. Generally, it is often installed at both ends in the width direction of a bridge with a low cross slope. The floor slab 50 is covered with a pavement portion 40 composed of a surface layer 41 and a base layer 42. Rainwater flowing on the surface of the surface layer 41 is collected in a drainage basin 10 and flows through a tubular portion 13 to a water pipe (not shown). A floor slab waterproof layer 43 is provided between the floor slab 50 and the pavement portion 40. The floor slab waterproof layer 43 is a sheet type or a coating film type, but in any case, it is adhered to the floor slab 50 by using a primer or the like, and has a high adhesive force. A headrace band 44 is provided between the drainage basin 10 and the base layer 42. Further, the drainage basin 10 is provided with a water guide pipe 21 for the purpose of improving drainage.

FIG. 3 shows a perspective view of the drainage basin 10. The outer peripheral surface of the drainage basin 10 is covered with the polymer cement mortar 15. As the polymer cement mortar 15, it is preferable to use a fast-curing polymer cement mortar, for example, it is preferable to use a "rubber latex mortar" manufactured by Pacific Materials Co., Ltd. The thickness of the polymer cement mortar 15 is preferably about 5 mm to 10 mm, and the layer is preferably formed with a uniform film thickness. The outer peripheral surface of the drainage basin 10 is not limited to the polymer cement mortar 15, and can be replaced as long as it has a function of increasing the adhesive force between the metal and the cement constituting the drainage basin 10. is there.

At this time, it is desirable that the outer peripheral surface of the drainage basin 10 is roughened to some extent by using sandblasting or the like to provide unevenness. The method of roughening the surface does not prevent the use of a method such as acid treatment using a chemical. Further, there are a case where the polymer cement mortar 15 is directly sprayed on the surface of the drainage basin 10 and a case where the polymer cement mortar 15 is sprayed on the drainage basin 10 after being painted. Further, although FIG. 3 shows that the polymer cement mortar 15 is applied to the entire outer peripheral surface of the drainage basin 10, it is sufficient that the outer peripheral surface portion of the concrete contact surface member is covered with the polymer cement mortar 15.

Since the drainage basin 10 of the first embodiment has the above configuration, it exhibits the actions and effects described below. Specifically, in the drainage basin 10 provided at the end of the floor slab 50 of the bridge 100, the polymer cement mortar 15 is applied to the outer peripheral surface of the drainage basin 10, so that the adhesive force with the floor slab 50 is improved. To do. As a result, it is possible to prevent a gap from being formed at the boundary between the floor slab 50 and the drainage basin 10.

This is because the polymer cement mortar 15 is applied to the outer peripheral surface of the drainage basin 10 in advance, so that the adhesive force between the drainage basin 10 and the floor slab 50 is improved when the floor slab 50 is constructed. Normally, when the bridge 100 is used, vibration or the like is generated, so that an environment in which a gap is likely to occur at the boundary between the drainage basin 10 and the floor slab 50 is created. However, by interposing the polymer cement mortar 15, the floor slab 50 adheres to the drainage basin 10 and a gap is less likely to occur. It has been confirmed that this adhesive force continues to exert its effect even when the bridge 100 is used.

According to the results confirmed by the applicant by experiments, the adhesion strength between the drainage basin 10 and the floor slab 50 is as low as ^{about 0.3 N / mm 2 when the polymer cement mortar 15 is not installed.} However, it was confirmed that when the polymer cement mortar 15 was applied, it was ^{significantly improved to about 3.3 N / mm 2 or more.} Further, when the drainage basin 10 was cast, the adhesion strength between the drainage basin 10 and the floor slab 50 was about 0.2 N / mm ^{2 unless the polymer cement mortar 15 was constructed, but when the polymer cement mortar 15 was constructed, the adhesion strength was about 0.2 N / mm 2.} The adhesion strength between the drainage basin 10 and the floor slab 50 was about 2.7 N / mm ² . As a result, it becomes difficult for a gap to be formed at the boundary between the drainage basin 10 and the floor slab 50, so that the drainage of the bridge 100 is guided to the inside of the drainage basin 10 and the drainage enters between the drainage basin 10 and the floor slab 50. Therefore, it is possible to prevent deterioration of the concrete of the floor slab 50 and the girder (not shown) near the drainage basin 10.

Then, the drainage basin 10 is supplied to the work site in a state where the polymer cement mortar 15 is applied to the outer peripheral surface of the drainage basin 10, so that it takes time and effort to improve the adhesive force of the drainage basin 10 at the work site. It is also preferable in that it does not take a long time and the quality can be maintained. This improves the workability of the bridge 100 and also leads to a reduction in construction time, which is another merit.

Next, a second embodiment of the present invention will be described. The second embodiment has almost the same configuration as the first embodiment, but the material of the drainage basin 10 is different. FRP is used as the material of the drainage basin of the second embodiment, and as pointed out in the problem, the surface thereof may have a lower adhesive force with concrete than the case of using a casting or a steel material. Therefore, improvement of the adhesive force can be expected by a method of spraying silica sand around the drainage basin 10 and then further spraying the polymer cement mortar 15. According to the experiment conducted by the applicant, when the silica sand was not sprayed and the polymer cement mortar 15 was not applied, the adhesion strength between the drainage basin 10 and the floor slab 50 was about 0.1 N / mm ² , but the silica sand was sprayed. adhesion strength in the case of is about 0.4 N / mm ^2, in the case of applying the polymer cement mortar 15 after construction blowing silica sand, catch basins 10 and adhesion strength of the floor plate 50 is 1.8 N / mm ² It has been confirmed that Therefore, it is desirable to spray silica sand on the drainage basin 10 to construct the polymer cement mortar 15.

In addition, the outer surface may be roughened by blasting without spraying silica sand around the drainage basin 10, or the surface may be roughened by chemical treatment. Even in this case, the polymer cement mortar 15 is applied. By doing so, improvement of adhesive force can be expected.

Although the embodiment of the drainage basin 10 according to the present invention has been described above, the present invention is not limited to this, and various changes can be made without departing from the spirit of the present invention. For example, the shape of the drainage basin 10 is described in FIGS. 1 to 3, but it does not prevent the application of the present invention to drainage basins having other shapes. Further, since the structure of the bridge 100 as shown in the cross-sectional view of the bridge 100 shown in FIG. 2 is merely an example, it does not prevent the drainage basin 10 of the present invention from being used for the bridge 100 having other structures.

10 Drainage basin 11 Square frame part 12 Tapered part 13 Cylindrical part 21 Water guide pipe 30 Wall height column 40 Pavement part 41 Surface layer 42 Base layer 43 Floor slab Waterproof layer 44 Water guide belt 50 Floor slab

Claims (3)

In the drainage basin provided on the floor slab of the bridge
A polymer cement mortar that improves the adhesion to the floor slab is applied and provided on the outer peripheral surface of the drainage basin.
The thickness of the layer formed by the polymer cement mortar shall be about 5 to 10 mm.
A drainage basin characterized by. In the drainage basin according to claim 1,
The outer peripheral surface of the drainage basin is provided with a large number of irregularities, on which the mortar is applied.
A drainage basin characterized by. In the drainage basin according to claim 1,
After spraying silica sand on the outer peripheral surface of the drainage basin,
Spraying the mortar on the silica sand,
A drainage basin characterized by.

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