JP6904937B2 - How to repair the reinforced concrete vertical wall of the tunnel guard passage - Google Patents

Description

The present invention relates to a method for repairing a reinforced concrete vertical wall of a tunnel observer passage.

The reinforced concrete vertical wall of the tunnel guard passage is exposed to a bad environment due to the exhaust gas of various vehicles passing through the tunnel, and therefore tends to deteriorate rapidly. In addition, the deterioration of the reinforced concrete vertical wall is more likely to progress due to salt damage caused by the salt-containing water contained in the antifreezing agent being splashed up as the vehicle travels. If such deterioration progresses, concrete debris may fall on the road surface and cause a serious traffic accident. In order to prevent accidents, it is necessary to promptly repair the deteriorated reinforced concrete vertical wall. There is.

Conventionally, as a method of repairing a deteriorated vertical wall made of reinforced concrete, for example, a rod is fixed to an anchor placed deep in the base wall surface, a tile panel is penetrated through the rod, and tiles are maintained at a predetermined distance from the base wall surface. After fixing the panel, a method of filling the space between the tile panel and the underlying wall surface with a mortar slurry having specific properties and hardening it to form a lightweight cellular concrete layer (Patent Document 1), a damaged part or fragility of the tiled wall surface. After peeling off the part and adjusting the unevenness with the anchor bolt attached to the wall surface and attaching the tile panel that also serves as a mold at a predetermined distance from the wall surface, the tile panel is prevented from swelling when filling with mortar. At the same time, a method of filling a fluid mortar between the tile panel and the wall surface (Patent Document 2) and the like have been proposed.

Japanese Unexamined Patent Publication No. 2014-148825 Japanese Patent No. 5761701

However, in the conventional repair method, it is necessary to place an anchor on the side surface of the vertical wall to fix the panel, and when the deteriorated part of the vertical wall is peeled off and removed, not only the deteriorated part but also the sound part is affected. Since it is necessary to remove it, it is a big problem that the repair work requires a lot of labor and time.
An object of the present invention is to provide a method for repairing a reinforced concrete vertical wall of a tunnel observer passage, which can reduce labor and shorten the construction period.

As a result of various studies, the present inventors removed the concrete at the top of the vertical wall made of reinforced concrete, then chipped the side surface of the vertical wall, and then placed a specific panel that also served as a formwork on the suspended surface at a predetermined interval. It was found that the reinforced concrete vertical wall of the tunnel guard passage can be repaired in a short construction period without much labor by injecting a specific mortar into the gap between the panel and the hanging surface.

That is, the present invention is a method for repairing a vertical wall made of reinforced concrete in a tunnel observer passage.
The first step of removing the concrete at the top of the vertical wall made of reinforced concrete,
The second process of hanging the cover on the side of the vertical wall made of reinforced concrete,
A third step of arranging a plurality of UFC panels for both formwork so as to be adjacent to each other at a predetermined interval from the fishing surface.
It provides a repair method including a fourth step of injecting a rust preventive-containing non-shrink mortar into a gap between a formwork-combined UFC panel and a chipping surface.

According to the present invention, the reinforced concrete vertical wall of the tunnel observer passage can be repaired in a short construction period without requiring a great deal of labor.

It is a schematic diagram which shows an example of the tunnel to which the repair method of this invention is applied. It is a figure which shows the reinforced concrete vertical wall part of the tunnel guard passage of FIG. It is a figure which shows an example of the repair method of this invention schematically. It is a figure which shows an example of the UFC panel which also serves as a formwork.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are designated by the same reference numerals, and duplicate description will be omitted. Also, for convenience of illustration, the dimensional ratios in the drawings do not always match those described.

FIG. 1 is a schematic view showing an example of a tunnel to which the repair method of the present invention is applied. FIG. 2A is a diagram showing a reinforced concrete vertical wall portion of the tunnel observer passage, and FIG. 2B is a diagram showing a reinforced concrete vertical wall portion seen from the roadway side.

As shown in FIG. 1, the observer passage 1 includes a reinforced concrete vertical wall 2 erected along the vertical direction of the tunnel on one end side of the roadway 3 in the tunnel, and a horizontal direction from the upper end of the vertical wall 2. It is provided with a passage portion 1a extended to. In the present specification, the “top end of the reinforced concrete vertical wall” refers to the end portion 2a of the reinforced concrete vertical wall 2 farthest from the bottom surface, as shown in FIG. 2 (a), and also “reinforced concrete”. As shown in FIG. 2A, the “side surface of the vertical wall” means the vertical surface 2b facing the roadway 3 side.

As shown in FIG. 2B, a plurality of handrail columns 4a separated from each other at predetermined intervals are installed on the upper surface of the reinforced concrete vertical wall 2. As shown in FIG. 2C, each support column 4a is fixed by post-installed anchors 4c and is erected upward from the upper surface of the reinforced concrete vertical wall 2. Further, the upper ends of the adjacent columns 4a are erected by the handrail rod 4b, and the handrail 4 is formed by the support column 4a and the handrail rod 4b.

The object of application of the present invention is a vertical wall 2 made of reinforced concrete, and the degree of deterioration thereof is as follows: The appearance grades shown in Table 1 below are "I (incubation period)" to "III-2 (late acceleration period)". The effect of the present invention is enjoyed when the corrosion grade of the reinforcing bar shown in Table 2 below is from "I (no rust adhered to the concrete surface)" to "III (no cross-sectional defect)". It is preferable because it is easy. That is, the repair method of the present invention can be suitably applied to those in which the reinforcing bars in the vertical wall concrete are not replaced or added.

Next, the repair method of the present invention will be described. The repair method of the present invention includes a first step, a second step, a third step, and a fourth step. Hereinafter, each step will be described in detail with reference to the drawings.

<First step>
The first step is a step of removing the concrete at the top end 2a of the reinforced concrete vertical wall 2.
Prior to this step, the construction anchor 4c is cut and removed after the handrail support 4a. Next, as shown in FIG. 3, the concrete at the top end 2a is removed together with a part of the post-installed anchor 4c embedded in the concrete. The amount of concrete removed from the top end 2a can be set as appropriate according to the deterioration status of the concrete, but since the concrete at the top end 2a has deteriorated due to rust or the like of the post-installed anchor 4c, the vertical wall 2 ceiling It is preferable to remove the concrete to about 200 mm from the edge. The concrete removal work can be performed by a general method, and for example, a wall saw or the like can be used.

Further, in the present invention, after removing the concrete from the top end portion 2a, as shown in FIG. 3, there may be a step of placing anchors 6 at predetermined intervals in the concrete removing portion. The anchor 6 may be placed before the third step, and in order to further increase the strength, deformed reinforcing bars may be arranged in the horizontal bars with respect to the vertical bars of the anchor 6. By placing the anchor 6 in this way, the upper end of the UFC panel can be fixed to the anchor 6 when arranging the UFC panel in the third step described later, so that the alignment becomes easy and the adjacent UFC panels are adjacent to each other. It is possible to suppress the non-landing with. The placement interval of the anchor 6 can be appropriately set according to the size of the UFC panel, but is usually about 250 mm.

<Second step>
The second step is a step of hanging the cover of the side surface 2b of the reinforced concrete vertical wall 2. In the chipping step, the deteriorated portion of the concrete may be removed from the upper surface of the side surface 2b of the vertical wall 2.
The amount of chipping can be appropriately set according to the deterioration state of the concrete as long as the vertical wall 2 made of reinforced concrete after chipping has a thickness that can withstand the back earth pressure, but is usually 30 to 50 mm. The chipping work can be performed by a general method, and for example, an electric hammer or an air pick can be used.

Further, in this step, as shown in FIG. 3, a step of providing a groove 8 in the lower end portion of the covering surface, that is, the foundation portion of the reinforced concrete vertical wall 2 may be provided. By providing the grooves 8 in this way, the lower end of the UFC panel can be dropped into the grooves 8 when arranging the UFC panels in the third step, which will be described later, which facilitates alignment and makes adjacent UFCs. It is possible to suppress the non-landing with the panel. The groove 8 can be formed not only before the chipping step or after the chipping step, but also together with the chipping step.
The depth of the groove 8 can be set appropriately as long as the lower end of the UFC panel can be embedded, but it is usually about 50 mm. Further, the depth of the groove 8 can be appropriately set in consideration of the distance from the hanging surface when arranging the UFC panel in the third step described later. The groove 8 can be formed by a general method, and for example, an electric hammer or an air pick can be used.

<Third step>
First, the UFC panel used in the present invention will be described.
In the present invention, the "UFC panel" is formed by molding Ultra High Strength Fiber Reinforced Concrete into a panel shape. For example, "design / construction guideline for ultra high strength fiber reinforced concrete (draft)". ) ”(Hereinafter referred to as UFC guideline), ultra-high strength fiber reinforced concrete, or ultra-high strength equivalent to various physical properties (air permeability coefficient, chloride ion diffusion coefficient) related to substance movement shown in UFC guideline. It can be manufactured using fiber reinforced concrete. By using ultra-high-strength fiber reinforced concrete in this way, it is possible to reduce the weight of the panel, and as a result, it is easy to transport and install with a small number of people, reducing labor and shortening the construction period. Can be done.

In the present invention, since the UFC panel is also used as a mold, characteristics such as high strength, high toughness, and high durability are required. For example, it is preferable to use a UFC panel that has the characteristics shown in Table 3 below.

The size of the UFC panel can be appropriately set according to the size of the reinforced concrete vertical wall, but the height is usually 800 to 1200 mm, preferably about 1000 mm, and the width is usually 500 to 1500 mm, preferably. Is 750 to 1200 mm, and the thickness is usually 10 to 50 mm, preferably 15 to 30 mm.
The shape of the UFC panel is not particularly limited as long as it can be installed horizontally with respect to the reinforced concrete vertical wall, and an example thereof is shown in FIG. The UFC panel 5 shown in FIG. 4A has a protrusion 5a on a part of a rectangular flat plate, and the protrusion 5a is provided with an opening 5b. Note that FIG. 4B shows a cross-sectional view of the UFC panel 5 shown in FIG. 4A along the I-I line. The UFC panel 5 shown in FIG. 4A includes a protrusion 5a having an opening 5b for embedding a handrail in a part of a rectangular flat plate. For example, the lower surface of the opening 5b shown in FIG. 4C. By attaching the insert anchor 5c to the handrail support, the handrail support can be easily installed. The sizes of the protrusions 5a and the openings 5b can be appropriately set according to the handrail support. For example, the thickness of the protrusion 5a is 10 to 30 mm, preferably 15 to 25 mm. Further, the number of openings 5b provided in the protrusion 5a can be appropriately set depending on the installation situation of the handrail, and the UFC panel shown in FIG. 4A is provided with two openings 5b. Further, as shown in FIG. 4B, the end portion of the opening 5b may be an open end, or may be a closed end as long as the handrail can be erected.
Further, the surface of the UFC panel 5 on the side to be filled with mortar, which will be described later, may be provided with irregularities or protrusions in order to improve adhesion to the mortar.

Next, the third step will be described.
The third step is a step of arranging a plurality of UFC panels 5 so as to be adjacent to each other at a predetermined interval from the fishing surface.
The UFC panels 5 are placed next to each other with the sides of the UFC panel 5 in contact with each other at a predetermined distance from the chipping surface, and as shown in FIG. 4 (d), the coupling pin 5d is used as a guide key to be adjacent to each other. The top position can be determined by inserting it into each of the holes 5e provided in the matching UFC panel 5. The coupling pin is, for example, a resin rod-shaped one, usually having a diameter of 8 to 12 mm and a length of 80 to 100 mm.
Further, as shown in FIG. 3, when the anchor 6 is placed on the top end 2a of the reinforced concrete vertical wall 2, the upper end of the UFC panel 5 is fixed to the metal fitting connected to the anchor 6. You may. For example, the bolt 7a may be fixed to the anchor 6 with a reinforcing bar clamp, the bolt may be passed through the UFC panel 5, and the end of the bolt may be fitted with the lip channel steel 7b to fix the UFC panel 5.
Further, as shown in FIG. 3, when a groove 8 is provided at the lower end of the reinforced concrete vertical wall 2, the lower end of the UFC panel 5 is dropped into the groove 8 at a predetermined distance from the fishing surface. The sides of the UFC panel 5 may be brought into contact with each other and placed next to each other. In this case, the lower ends of the UFC panel 5 may be fixed at predetermined intervals via metal fittings. For example, the exposed surface on the roadway side of the lower end of the UFC panel 5 and the roadway surface may be fixed with the L-shaped metal fitting 9.

Further, the UFC panel 5 may be arranged after the resin tape is attached to the side surface and / or the bottom surface of the UFC panel 5. This makes it possible to prevent mortar from leaking between the UFC panels 5 and from the bottom of the UFC panel 5 in the fourth step. Examples of the resin tape include a gap tape in which an adhesive layer is formed on one side of a sponge-like material.

The distance from the chipping surface to the UFC panel 5 can be appropriately set depending on the amount of chipping, but is usually 10 to 80 mm, preferably 15 to 65 mm. When the UFC panel 5 has a protrusion 5a, it is sufficient that the portions other than the protrusion 5a secure the above interval.

<Fourth step>
The fourth step is a step of injecting a rust preventive-containing non-shrink mortar into the gap 10 between the UFC panel 5 and the fishing surface.
As the non-shrink mortar, various non-shrink mortars known as materials for civil engineering and construction can be used.
Examples of the rust preventive include amines such as tertiary amines; nitrites such as calcium nitrite and lithium nitrite; phosphates; chromate; organic phosphate esters; ester salts; organic acids; sulfonic acids; Alkylphenol; mercaptan; nitro compound and the like can be mentioned. Two or more kinds of rust preventives may be used in combination. The rust preventive may be added when kneading the non-shrink mortar, and the amount of the rust preventive added is usually 0.1 to 0.5% by mass, preferably 0.2 in the non-shrink mortar. ~ 0.4% by mass.

The injection of the rust preventive-containing non-shrink mortar can be performed by a general method, and for example, a squeeze pump or the like can be used.
Further, the injection of the rust preventive-containing non-shrink mortar is preferably performed in a plurality of times from the viewpoint of reliability of mortar filling and improvement of work efficiency. For example, after inserting an injection hose into the gap 10 at the upper end of the UFC panel 5 and injecting rust preventive-containing non-shrink mortar from the bottom to the middle of the reinforced concrete vertical wall 2 to form the first mortar layer, 4 to 4 to Cure for about 6 hours. Next, a rust preventive-containing non-shrink mortar is injected to the upper end of the chipping surface to form a second mortar layer, and then cured for about 4 to 6 hours. Next, concrete is cast up to the upper surface of the UFC panel 5 to form the top end 2a of the reinforced concrete vertical wall 2. An expansion material may be added when placing concrete, and examples of the expansion material include a lime-based expansion material suitable for JIS A 6202 concrete expansion material. The amount of the leavening agent added is usually 10 to 30 kg per ^{1 m 3 of concrete.}

After confirming that the concrete at the top end 2a of the reinforced concrete vertical wall 2 has hardened, a handrail is installed on the upper surface of the reinforced concrete vertical wall 2. For the installation of the handrail, for example, after fixing the handrail mounting jig to the upper surface of the reinforced concrete vertical wall 2 with bolts, the handrail strut may be erected on the handrail mounting jig, and the handrail rod may be erected on the handrail strut. ..

Further, in the third step, among the metal fittings used for fixing the UFC panel 5, the metal fittings protruding toward the roadway 3 side can be removed. In this case, the trace hole after the removal of the metal fitting can be filled with non-shrink mortar.

<Fifth step>
After the fourth step, it may have a fifth step of filling the joints between the UFC panels 5 with a filler. Thereby, deterioration of concrete can be further prevented. Examples of the filler include mortar, resin and the like. The filler can be filled by a general method.

The present invention has been described in detail above based on the embodiment. However, the present invention is not limited to the above embodiment. The present invention can be modified in various ways without departing from the gist thereof. For example, in the above embodiment, the UFC panel having the protrusion shown in FIG. 4A is used, but the rectangular flat plate-shaped UFC panel shown in FIG. 4E can also be used. In this case, when installing the handrail, after the fourth step, a post-installed anchor for fixing the handrail support to the top surface of the reinforced concrete vertical wall 2 is installed, and after the handrail support is attached, the handrail rod is erected. good.

1 Observer passage 2 Reinforced concrete vertical wall 3 Roadway 4 Handrail 5 UFC panel 6 Anchors 7a, 7b, 9 Metal fittings 8 Grooves 10 Gap

Claims (6)

The first step of repairing the reinforced concrete vertical wall of the tunnel guard passage and removing the concrete at the top of the reinforced concrete vertical wall,
The second process of hanging the cover on the side of the vertical wall made of reinforced concrete,
A third step of arranging a plurality of formwork-combined UFC panels having an opening at the upper end so as to be adjacent to each other at a predetermined interval from the hanging surface.
A repair method comprising a fourth step of injecting a rust preventive-containing non-shrink mortar into the gap between the UFC panel that also serves as a formwork and the hanging surface. The second step further includes a step of providing a groove at the lower end of the fishing surface.
In the third step, a plurality of formwork-combined UFC panels are arranged so as to be adjacent to each other at a predetermined distance from the hanging surface by dropping the lower ends of the formwork-combined UFC panels into the groove.
The repair method according to claim 1. In the third step, after the resin tape is attached to the side and / or bottom of the UFC panel that also serves as a formwork, a plurality of UFC panels that also serve as a formwork are placed next to each other at a predetermined interval from the hanging surface. The repair method according to claim 1 or 2, wherein the top position of the UFC panel is determined by arranging and inserting a coupling pin into a hole on the side surface of the adjacent UFC panel. After the first step and before the third step, the step of placing anchors at predetermined intervals in the concrete removing portion at the top end is further included.
After the third step and before the fourth step, the step of fixing the upper end portion of the UFC panel also used as a formwork to the metal fitting connected to the anchor is included.
The repair method according to any one of claims 1 to 3. The invention according to any one of claims 1 to 4, further comprising a step of fixing the lower end portion of the UFC panel that also serves as a formwork at predetermined intervals via a connecting metal fitting after the third step and before the fourth step. Repair method. The repair method according to any one of claims 1 to 5 , further comprising a fifth step of filling the joints between the UFC panels that also serve as formwork with a filler after the fourth step.

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