JP4415705B2 - Method for reinforcing underground concrete structure and underground concrete structure - Google Patents

Description

  The present invention relates to the reinforcement of concrete structures, and in particular, is a technique that can be suitably used for reinforcing box culverts and manholes of infrastructure equipment such as electricity, water, and gas, which are narrow construction conditions. .

  With the lapse of many years, a concrete structure needs to be reinforced due to an influence such as a decrease in strength due to deterioration of a main body structure and a response to an applied load increased by a change in external force. Conventionally, as a method for reinforcing a deteriorated concrete structure, for example, a method of excavating an existing concrete structure from the outside to remove the deteriorated portion and then newly increasing the thickness with reinforced concrete to improve the strength is used. It was.

  However, since the reinforcement method requires a formwork for placing concrete, a large work space is required for reinforcement. Therefore, it has been difficult to apply to the reinforcement of concrete structures in narrow places such as manholes.

  In view of such a problem, as a method for reinforcing a concrete structure of a manhole that is a narrow space, a method of sticking a fiber sheet in which high-strength fibers such as carbon fibers are woven into a sheet shape to the concrete structure to be reinforced Was used. According to this reinforcing method using a fiber sheet, it is only necessary to paste a sheet containing fibers in advance, so that it could be performed even in a narrow space. Furthermore, since the fiber sheet manufactured in advance is used, it was possible to reinforce with a certain quality and sufficiently reinforce the strength. However, although this fiber sheet can sufficiently reinforce concrete against tension and bending, it has a problem that it cannot sufficiently reinforce concrete against shear. Furthermore, depending on the construction location, the reinforcement location may leak, and it may be difficult to bond the fiber sheet to such a leak location.

  The present invention has been made in view of the various problems described above, and can be reinforced against any load of shearing, bending, and tensioning on a concrete structure. It is a technical problem to provide a method for reinforcing a concrete structure with a limited number of construction sites that can be used.

  The reinforcing panel for a concrete structure according to the present invention is configured as follows in order to solve the above technical problem. A panel for reinforcing a concrete structure by sticking to a concrete structure, the cement mortar panel containing a short fiber, and a fiber sheet containing a fiber, the cement mortar panel and the fiber The sheet is polymerized.

  The present invention is a panel used to reinforce an existing concrete structure. Due to the above configuration, the fiber contained in the cement mortar and the fiber contained in the fiber sheet can be used for the tensile stress and bending stress of the concrete structure. Can be reinforced. Hereinafter, the structure of the reinforcing panel for a concrete structure according to the present invention will be described in detail.

  First, the short fiber is a fiber having a short fiber length or a short cut, and when used as a reinforcing material, the short fiber exists in a discontinuous state in the composite material. Therefore, the tensile and bending strength of cement mortar can be improved by containing short fibers in cement mortar. Examples of the short fiber include steel, stainless steel, vinylon, police ethylene, polypropylene, carbon fiber, glass fiber, nylon, carbon, and aramid. In addition, since this short fiber mixes in a cement mortar material instead of a reinforcing bar, what does not rust like a reinforcing bar is desirable.

  As described above, the cement mortar panel used in the present invention contains short fibers. By mixing the short fibers into the cement mortar, the tensile strength is reduced by about 10% compared with the cement mortar containing no short fibers. It can be improved about 10 to 20 times. However, it is difficult to obtain sufficient strength as compared with reinforcing bars only with these short fibers. Therefore, a fiber sheet was polymerized on a cement mortar panel in order to increase the tensile strength of the reinforcing panel when used in combination with short fibers. The fiber sheet is preferably one that can efficiently add tensile strength. For example, a carbon fiber sheet or an aramid fiber sheet can be used, and a carbon fiber having particularly excellent characteristics can be preferably used. The cement mortar panel may be a concrete panel made of concrete.

  The carbon fiber is a fiber obtained by heating and carbonizing an organic fiber at 700 to 1800 ° C. in a nitrogen stream. Carbon fiber has excellent properties such as high specific strength, high specific modulus, conductivity, heat resistance, low expansion coefficient, chemical stability, self-lubricity, and high thermal conductivity. Examples of the type of carbon fiber include filament, tow, cloth, blade and the like. In addition, the present invention can be easily handled when reinforcing, and the fibers are formed into a sheet shape so that it can be applied to various places.

The strength of the fiber sheet depends on the amount of fiber and the thickness of the sheet. Therefore, it is desirable to change appropriately according to design conditions. The fiber amount can be expressed by a basis weight. For example, a carbon fiber sheet having a basis weight of 200 (g / m ² ) and a thickness of 0.011 cm has a tensile strength of 5500 (N / mm ² ). The tensile strength per 1 m ^{2 of} this carbon fiber sheet is 55000 (kg / cm ² ) × 0.011 (cm) × 100 (cm) × 1/3 (safety factor) = 20167 (kg). When this value is replaced with a reinforcing bar, the tensile strength per meter is π × 19 × 19/4 (cross-sectional area) × 4 (number) × 1600 (allowable tensile strength of reinforcing bar) = 18137 kg in the case of D19 mm 200 pitch bar arrangement. Become. Comparing these two calculated values, it can be seen that the value of the carbon fiber sheet is larger and has a higher tensile strength than the reinforcing bar. On the other hand, when the calculated values are compared and the value of the carbon fiber is small, the amount of fiber may be increased or the thickness may be amplified depending on the reinforcing state.

  The cement mortar panel according to the present invention is preferably manufactured in advance at a factory or the like. Depending on the reinforcement site, there may be a narrow space where almost no space is available for the formwork, and when cement mortar panels are installed on site, short fibers cannot be mixed evenly, maintaining a certain level of quality. There are cases where it is not possible. On the other hand, it is preferable to construct a cement mortar panel in advance in a factory or the like because it is possible to improve the workability, quality stability, and cost. Further, the shape of the cement mortar panel is desirably manufactured according to the reinforcing portion, and can be various shapes such as a flat plate, a curved plate, a concavo-convex plate, and a hunched plate. In addition, the thickness of the cement mortar panel is not particularly limited. If it is too thin, the cement mortar panel may be warped and cracked. If it is too thick, handling, installation, etc. may be difficult due to its own weight. From such a viewpoint, the present applicant conducted various experiments and studies on the thickness of the cement mortar panel. As a result, the thickness of the cement mortar panel is preferably 15 mm or more and 60 mm or less.

In the present invention, the cement mortar panel and the fiber sheet are polymerized to increase the strength of both members. Therefore, it is desirable that the cement mortar panel and the fiber sheet are fixed. Examples of the fixing method include a method of bonding both members using an adhesive, and a method of screwing using a bolt or the like. The adhesive may be any adhesive as long as the cement mortar panel and the fiber sheet can be integrated with a predetermined adhesive strength. For example, an epoxy adhesive, a urethane adhesive, a silicone adhesive, a rubber adhesive, and an acrylic adhesive. Adhesives, polymer cement adhesives, vinyl ester adhesives, polyester adhesives, and polyolefin adhesives can be used.

  Moreover, as for the panel for reinforcement of the concrete structure which concerns on this invention, it is desirable to superpose | polymerize two or more said cement mortar panels and fiber sheets. As described above, the thickness of the cement mortar panel is preferably 15 mm or more and 60 mm or less. Further, the thickness of the fiber sheet is preferably about 0.1 mm from the viewpoint of easy handling. That is, the cement mortar panel and the fiber sheet are both limited to a certain thickness from the viewpoint of workability and the like. However, the strength of the reinforcing panel is limited depending on the amount of fibers mixed in and the thickness of each member, and the amount of fibers mixed in is also limited. Therefore, it is necessary to increase the thickness in order to obtain high strength. Thus, when it is desired to increase the strength of the reinforcing panel, it is desirable to polymerize a plurality of layers of cement mortar panel and fiber sheet. Thereby, based on the intensity | strength of each member, the panel for reinforcement of desired intensity | strength can be obtained by combining these.

  Furthermore, the reinforcing panel for a concrete structure according to the present invention may be characterized in that a plurality of layers of cement mortar panels and fiber sheets are alternately arranged. In order to increase the strength of the reinforcing panel, the arrangement method is not particularly limited when a plurality of cement mortar panels and fiber sheets are polymerized. However, for example, in a factory or the like, a cement mortar panel and a fiber sheet bonded in advance are made into one layer, and this layer is combined to make a reinforcing panel, so that the reinforcement having a desired strength can be made more efficiently and easily. Panel can be obtained. As another arrangement method, a fiber sheet may be arranged between cement mortar panels. As described above, the fiber sheet has a high tensile strength even if it has a small thickness. However, if the surface is scratched or the like, the tensile strength of the portion may be reduced. On the other hand, it is desirable to form the fiber sheet with a small thickness from the viewpoint of ease of handling and the like, and there is a possibility that a crack may occur from the scratched portion. For this reason, it is desirable to dispose cement mortar panels that are hardly damaged or the like on the outside and dispose the fiber sheet between the cement mortar panels. The fiber sheet disposed between the cement mortar panels may be a single sheet or a plurality of sheets, and it is desirable to design appropriately so as to obtain a necessary reinforcing strength.

  The present invention is also a method for reinforcing a concrete structure using the reinforcing panel, wherein the reinforcing panel is fixed to a wall to be reinforced with an anchor, and an adhesive is filled in a gap between the reinforcing panel and the wall. And the reinforcing panel and the wall surface are integrated. According to the reinforcing method, the wall surface can be easily and effectively reinforced.

  As described above, according to the method for reinforcing a concrete structure according to the present invention, it is possible to effectively reinforce the cement mortar panel and the fibers of the fiber sheet. It is possible to reinforce against the load. Further, the reinforcing panel is small in thickness and does not involve a bar arrangement work as in the prior art, so that there are few restrictions on construction sites, and it can be suitably used even in narrow spaces. In addition, by manufacturing the reinforcing panel in advance in a factory or the like, the work on site can be greatly reduced, so that the construction period can be shortened.

  Hereinafter, an embodiment of a method for reinforcing a concrete structure according to the present invention will be described. This embodiment is a reinforcement of an existing box culvert. This box culvert has an underground power transmission line, and has a manhole at the top as an entrance for inspection and the like. FIG. 1 is a plan view of a box culvert, and FIG. 2 is a view taken in the direction of arrow A in FIG. As shown in each figure, the wall surface 4 of the box culvert is formed with a plurality of power transmission line conduits 4a for drawing in the power transmission line, and in this embodiment, the wall surface 4 below the power transmission line conduit 4a is reinforced. I do. As for the deterioration state, cracks occur in the concrete, and water leaks from the cracked parts.

  The reinforcing panel 1 used in the present embodiment will be described. FIG. 3 is a perspective view of the reinforcing panel 1. The reinforcing panel 1 was manufactured in a state where a cement mortar panel 2 and a fiber sheet 2 were polymerized one layer at a factory in advance. The reinforcing panel 1 is obtained by bonding a cement mortar panel 2 mixed with polypropylene fibers 2a as short fibers and a fiber sheet 3 made of carbon fibers. This reinforcing panel 1 is 200 × 20 × 3 (cm) and the weight per sheet is set to 30 kg in consideration of workability on site.

  The cement mortar panel 2 is a panel in which polypropylene fibers 2a are mixed in cement mortar and has the following characteristics. (1) Since the polypropylene fiber mixed as a short fiber does not rust, the cement mortar panel itself does not rust. (2) The quality is stable because it is manufactured in advance at the factory. (3) The relative kinematic modulus in 300 cycles according to the freeze-thaw test method is 80% or more, and is excellent in weather resistance and durability. (4) Since polypropylene fiber is mixed, bending and tensile strength are large, and initial cracking resistance is large compared with cement mortar not mixed with polypropylene fiber. (5) The compressive strength is 100 N / mm2, and the resistance to wear is high. (6) Polypropylene fiber is free from problems such as dioxin and environmental hormones, and is therefore environmentally friendly and can be treated as industrial waste similar to cement mortar containing no fiber. (7) Bending toughness is large.

As described above, the cement mortar panel 2 according to the present embodiment. It has various excellent features. Moreover, about the cement mortar panel 2 used for this Embodiment, the experiment which investigates compression, tension, and bending strength was conducted. The results are shown in Table 1.

Next, the carbon fiber sheet 3 used in the present embodiment is manufactured with a basis weight of 200 (g / m ² ), and the thickness thereof is 0.111 mm. As a result of experimenting the tensile strength of the carbon fiber sheet 3, a result of 3,500 (N / mm ² ) or more was obtained. That is, it was found to have a high tensile strength. The reinforcing panel 1 according to the present embodiment is a panel in which a cement mortar panel 2 and a carbon fiber sheet 3 are overlapped. A plurality of the panels are overlapped according to design conditions and fixed to the wall surface 4 to be integrated. The wall surface 4 is reinforced by the above.

First, the reinforcement of the wall surface 4 to be reinforced is examined. The reinforcement study will be described in detail based on the flowchart shown in FIG. In step 11, the proof stress for bending, shearing and punching shearing of the existing wall surface is calculated. This is for calculating the proof stress of the wall surface to be reinforced and confirming the proof stress in the existing state. Although detailed calculation is omitted here, the results of bending, shearing, and punching shear strength are obtained.

  In step 12, the current state of the existing wall surface and reinforcement are examined. In the present embodiment, in the confirmation of the proof stress, it was obtained that both had proof strength, but the current deterioration of the wall surface caused cracks in the concrete and water leakage from the cracked portions. ing. In view of such a situation, the cause of the difference between the calculation result obtained in step 11 and the current state is examined. One possible reason for this is that the design load was underestimated. That is, the factors such as the earth pressure, water pressure, etc. that are different from the current values in the calculation of the proof stress, and the fact that an unexpected upper load is acting are factors. As a second factor, it is conceivable that the side surface, the top plate, and the true wall are not integrally constructed at the time of construction of the wall surface. In the present embodiment, as a result of various studies, it is determined that the current wall surface deterioration is due to these factors, and a reinforcement plan is created from the calculation result and the deterioration state.

In step 13, the shear strength when the reinforcing panel based on the reinforcement plan is attached to the wall surface is calculated. A schematic diagram modeling the reinforcement of the wall according to the present embodiment is shown in FIG. The wall surface to be examined this time is a 1.8 m × 2.7 m wall surface. The earth pressure received by the wall surface is calculated in consideration of the distance from the ground surface, the specific gravity of the soil, and the like. The result is shown in FIG. Further, the shearing force acting as a simple beam is obtained with the trapezoidal load shown in FIG. The calculation process is shown in FIG. Based on the calculated values calculated in FIGS. 6A and 6B, the shear force of the entire working surface generated on the wall surface is obtained.
The acting shear force per unit area is
τ = 4.725 + 2.286 = 7.011 (t / m)
The acting shear force of the entire working surface is a value obtained by multiplying this by a total length of 2.7 (m).
W = 7.011 × 2.7 = 18.9 (t)

Next, evaluation when the reinforcing panel 1 is attached to the wall surface 4 is performed. The reinforcing panel 1 used here is one in which the two reinforcing panels 1 are used so that the carbon fiber sheets 3 face each other. This reinforcing panel 1 has an allowable shearing force of 10.1 N / m ² and an allowable bending stress of 25.2 N / m ² . The reinforcing panel 1 is attached to the wall surface 4 using the anchor 5. The anchor 5 is used to integrate the reinforcing panel 1 and the wall surface 4, and it is the fixing anchor 6 that receives the shearing force.

  Here, the construction plan of the anchor 6 is examined. When the anchor anchor 6 having an average shearing force of 4.9 t is used and the safety factor is 3, the allowable shearing force is 4.9 / 3 = 1.6 t. Here, since the acting shear force of the wall surface 4 is 18.9 t, the required number of anchors is 18.9 / 1.6 = 12. The anchor pitch is calculated as 2.7 / 12 = 0.225 m. In consideration of the safety factor 2 in this calculated value, the fixing anchors are 12 × 2 rows.

When the reinforcing panel 1 is fixed to the wall surface 4 with the number of fixing anchors calculated in the above calculation, a shearing force is received at a portion corresponding to the column 7 of the reinforcing panel 1 (part A in FIG. 5A). The shear strength resistance generated in step 1 is examined (step 14).
When the reinforcing panel is calculated as a simple beam, the acting shear force per unit length is
τc = S / bd = 7.011 × 1000 / (100 × 6) = 11.685 (kg / cm ² )
On the other hand, the allowable shearing force τp of the two reinforcing panels overlapped with a safety factor of 3,
τp = 10.1 × 1/3 = 3.37 (N / mm ² ) = 34.4 kg / cm ²
When this value is compared, τp> τ, and therefore, it is evaluated that it has a shear strength acting on the column portion.

As step 15, the bending strength against bending stress due to earth pressure or the like on the back surface of the wall surface is examined. The bending test of the present embodiment was performed in accordance with JIS A1106-1993 “Concrete bending strength test method”. The bending strength σc acting on the reinforcing panel from the wall surface is
σc = MX1 / bd2 × 1 / LC = 1.075 × 105 / (100 × (62)) × 6.0 = 179.16 kgf / cm ² = 17.6 N / mm ²
On the other hand, the allowable bending stress σp of the two reinforcing panels overlapped is assumed that the safety factor is 1.4.
σp = 25.2 / 1.4 = 18.0 N / mm ²
When this value is compared, it is evaluated that it has bending strength because σp> σc.
As a result of the above examination, since it has been evaluated that the existing wall surface 4 can be reinforced by the reinforcing panel 1, the reinforcing panel 1 having two layers as the reinforcement plan is used for reinforcement.

  Next, the construction of the reinforcing panel 1 will be described based on the flowchart shown in FIG. First, as a preparatory work, wire protection and wastewater treatment are performed (step 21). The wall surface 4 to be reinforced is provided with a power transmission line port 4a. Since the power transmission line is drawn into the power transmission line port 4a, it is necessary to protect the power transmission line. Further, since water leaks from the cracked portion of the wall surface 4 and is stored in the box culvert, the previously stored water is removed.

  Water stoppage and water transfer treatment of the water leakage portion of the wall surface 4 to be reinforced are performed (step 22). In the state where water leakage has occurred on the wall surface 4, the reinforcing panel 1 cannot be attached. Therefore, a water-stopping material such as a urethane-based water-stopping material is injected into the water leakage portion. A water guide pipe is installed at a location where water cannot be sufficiently stopped by the injection of the water stop material, and water leakage from the wall surface 4 to be constructed is stopped.

  The wall surface 4 to be reinforced is suspended and cross-sectional repaired (step 23). When the deterioration of the wall surface 4 is severe, it may be difficult to integrate with the reinforcing panel 1 as it is and attachment may be difficult. In such a case, the wall surface 4 is suspended and the cross section is repaired. In this embodiment, since the deterioration state was severe, the wall surface 4 was suspended by 5 cm, and cracks and cross-sectional defects were filled with polymer cement mortar for repair.

  After the wall surface 4 is repaired, the first reinforcing panel 1 is attached (step 24). The first-layer reinforcing panel 1 is set at an appropriate location, and the gap between the reinforcing panel 1 and the wall surface 4 is filled with an adhesive. Next, the second-layer reinforcing panel 1 is attached (step 25). Adhesion is applied between the first and second reinforcing panels 1 with an adhesive. In the present embodiment, the first and second reinforcing panels 1 are bonded together using an epoxy resin as an adhesive. In addition, the carbon fiber sheet 3 of the reinforcing panel 1 is easily scratched on the surface, and there is a risk that the strength at that location may be reduced if the scratch is applied. Therefore, it is desirable that the second-layer reinforcing panel 1 has the carbon fiber sheet 3 disposed on the inner side. In this embodiment, the carbon-fiber sheet of the first-layer reinforcing panel and the second-layer reinforcing panel are arranged. Polymerization was conducted with the carbon fiber sheet in contact.

  After setting the reinforcing panel 1 for the necessary layers, the reinforcing panel 1 is fixed to the wall surface 4 with the anchor 5 (step 26). After fixing with the anchor 5, if necessary, the periphery of the reinforcing panel 1 and the joints are sealed using an epoxy resin putty. Next, it is inspected whether or not the wall surface 4 and the reinforcing panel 1 are integrated (step 27). This is because if there is a gap between the wall surface 4 and the reinforcing panel 1 and they are not integrated, the reinforcing effect of the reinforcing panel 1 is not sufficiently exhibited. In the present embodiment, the air gap is inspected by hitting the surface of the reinforcing panel 1. As a result, several voids were confirmed, and the vicinity was drilled and filled with epoxy resin to close the voids.

By constructing the reinforcing panel 1 in this way, the wall surface 4 and the reinforcing panel 1 can be integrated, and the wall surface 4 can be cracked, bent and sheared, and wall displacement due to water pressure and earth pressure is suppressed. Is possible. However, even if the wall surface 4 and the reinforcing panel 1 are integrated, if the integration of the concrete and the structure is insufficient, the strength (or strength) against the hydraulic power and earth pressure necessary for the structure may not be obtained. is there. Therefore, next, the support column 7 is placed on the side wall 8 adjacent to the reinforced wall surface 4 (step 28). In this embodiment, fixing anchors 6 are driven on both side walls 8 adjacent to the reinforced wall surface 4, and reinforced concrete columns 7 are driven. By placing the fixing anchor 6, integration with the concrete structure can be achieved.

  As described above, according to the present embodiment, the reinforcement panel 1 and the wall surface 4 are integrated by constructing the reinforcement panel 1 of the necessary layer on the wall surface 4 to be reinforced, thereby facilitating the reinforcement of the wall surface 4. Could be done. Moreover, compared with the conventional reinforcement method, since a bar arrangement work, concrete placement work, etc. are unnecessary, construction efficiency was able to be improved.

  In the present embodiment, the wall surface 4 is reinforced using the reinforcing panel 1 having two layers, but the number of layers is preferably various layers depending on the wall surface 4 to be reinforced. For example, FIG. 8 is a schematic view of a wall surface to which a reinforcing panel 1 having three layers is attached. When attaching the reinforcing panel 1 composed of three layers, the first layer and the second layer have the carbon fiber sheet 3 portion disposed on the surface, and the third layer has the carbon fiber sheet 3 portion disposed on the back surface. . This is for protecting the carbon fiber sheet 3, and even when the number of layers increases, it is desirable to dispose the cement mortar panel 2 on the surface of the uppermost layer portion. In addition, although the construction method can use the said construction method even if the number of layers differs, when there are many layers, there exists a possibility that work efficiency may fall if it attaches to a wall surface for every layer. Therefore, when the number of layers is large, if necessary, the layers may be bonded in advance, and the reinforcing panel bonded with the required number of layers may be attached to the wall surface.

  In the present embodiment, a reinforcing panel is manufactured in advance at a certain standard at a factory, and these are combined to reinforce the wall surface. Therefore, it is necessary to integrate adjacent reinforcing panels for each layer. Examples of a method for joining adjacent reinforcing panels include a method using an adhesive and a method of providing a joint member at a joint between the reinforcing panels. The joint member only needs to be configured to be able to join adjacent reinforcing panels. For example, the joint members 10a and 10b shown in FIG. 9 can be exemplified. The joint members 10a and 10b are provided with a protrusion at a joint portion of one reinforcing panel 1 and a groove portion fitted to the protrusion at a joint portion of the other reinforcing panel 1. According to the joint members 10a and 10b, the reinforcing panels 1 can be easily connected. When a gap is generated between the protrusion and the groove, it is desirable to fill the gap portion with a filler in order to integrate the adjacent reinforcing panels and close the gap. Moreover, the cross-sectional shape of the protrusion and the groove may be a trapezoid as shown in FIG. 9A or a semicircular shape as shown in FIG. 9B. However, by using the joint member 10b having a semicircular cross section, the angle at which the adjacent reinforcing panels 1 are joined to each other can be made different. Therefore, even if the wall surface to be reinforced is distorted, It is possible to arrange the reinforcing panel 1 according to 4, which is preferable.

  Next, an example of arrangement of reinforcing panels for each layer will be described. As described above, if joint portions are arranged in a certain direction across a plurality of layers that join adjacent reinforcing panels for each layer, the strength at the joint portions may be reduced. In order to prevent such a decrease in strength, when using a reinforcing panel composed of a plurality of layers, it is desirable to vary the arrangement direction of the reinforcing panels for each layer. FIGS. 10A and 10B are arrangement examples of the reinforcing panel 1 having three layers, and show the arrangement directions from the first layer to the third layer. In any arrangement example, the parallel direction is different for each layer. As described above, by disposing the reinforcing panel 1, it is possible to prevent a decrease in strength even at a joint portion between the adjacent reinforcing panels 1.

In this embodiment, the reinforcing panel is used to reinforce the box culvert. However, the reinforcing panel can be used to reinforce various places. For example, slab reinforcement,
Examples include reinforcement of caves and bridges. Moreover, since the reinforcing panel according to the present invention can have various shapes, the shape of the wall surface to be reinforced is not limited to a flat surface, and may be a curved surface.

<Test example>
A test for verifying the strength of the reinforcing panel according to the present invention was conducted. The test method was carried out according to the “Bending Toughness Test” of JSCE-G552-1983. The specimens are three bodies: unreinforced concrete 31, D19 mm pitch reinforced concrete 32, and reinforcing panel 33 according to the present invention (see FIG. 11). As the reinforcing panel 33, a panel obtained by polymerizing a cement mortar panel mixed with polypropylene fibers and a carbon fiber sheet having a basis weight of 200 g / m ² was used. Each specimen 31, 32, 33 was placed on a two-point supported test jig (bottom) 35, a test jig (top) 34 was placed on the top, a load was applied, and strain against the load was measured. (See FIG. 12). The result is shown in FIG. As is apparent from the test results, it was found that the reinforcing panel 33 according to the present invention has higher strength than the other two bodies.

It is a top view of the box culvert used as the reinforcement object of this Embodiment. It is A arrow directional view of FIG. It is a perspective view of the panel for reinforcement concerning this embodiment. It is a flowchart which shows the reinforcement examination procedure which concerns on this Embodiment. It is the schematic of the state which attached the reinforcement panel (2 layers) which concerns on this Embodiment to the wall surface. It is the figure which showed the calculation process of the earth pressure which the wall surface which should reinforce which concerns on this Embodiment receives. It is a flowchart which shows the construction procedure of the wall surface reinforcement which concerns on this Embodiment. It is the figure which showed the example of arrangement | positioning of the reinforcement panel (3 layers) which concerns on this Embodiment. It is the figure which showed the joint member between reinforcement panels. It is the figure which showed the example of arrangement | positioning of the panel for reinforcement. It is sectional drawing of the test body of the strength verification test of a reinforcement panel. It is the figure which showed the outline of the test of the strength verification test of a reinforcement panel. It is a test result of the strength verification test of a reinforcing panel.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reinforcing panel 2 Cement mortar panel 2a Polypropylene fiber 3 Carbon fiber sheet 4 Wall surface 5 Anchor 6 Anchor anchor 7 Post 8 Side wall 10 Joint member

Claims (7)

Reinforcement having a cement mortar panel containing short fibers and a fiber sheet containing fibers, the cement mortar panel and the fiber sheet being polymerized, and having at least the same shear strength and bending strength as the wall to be reinforced A method of reinforcing an underground concrete structure using a construction panel,
A wall surface different from the wall surface to be reinforced, and connected to a column anchored to the wall surface adjacent to the wall surface to be reinforced, and the reinforcing panel is independent of the wall surface to be reinforced. Installation process on the wall to be reinforced;
An underground process comprising: an integration step of filling an adhesive into a gap between the reinforcing panel and the wall surface to be reinforced, and integrating the reinforcing panel and the underground concrete structure. How to reinforce a structure. In the integration step, a water-stopping material that stops water leakage from the wall surface to be reinforced is injected into a water leakage portion of the wall surface to be reinforced, and the bonding is performed in a gap between the reinforcing panel and the wall surface to be reinforced. 2. The method for reinforcing an underground concrete structure according to claim 1, wherein the reinforcing panel and the underground concrete structure are integrated by filling with an agent. The underground concrete structure has the wall surface to be reinforced and a side wall perpendicular to the wall surface to be reinforced.
In the installation step, the reinforcing panel is connected to a column that is different from the wall to be reinforced and is anchored to the side wall as a wall adjacent to the wall to be reinforced. The method for reinforcing an underground concrete structure according to claim 1 or 2, wherein the reinforcing method is provided on the wall to be reinforced independently of the wall to be reinforced. The underground concrete structure is a box culvert having the wall surface to be reinforced and a side wall orthogonal to the wall surface to be reinforced.
The wall surface to be reinforced of the box culvert is provided with a plurality of power transmission line inlets for drawing a power transmission line,
In the installation step, a wall surface different from the wall surface to be reinforced, and connecting a column anchored to the side wall as a wall surface adjacent to the wall surface to be reinforced and an end portion of the reinforcing panel, The method for reinforcing an underground concrete structure according to claim 1, wherein the reinforcing panel is provided on the wall surface to be reinforced independently of the wall surface to be reinforced. Reinforcement having a cement mortar panel containing short fibers and a fiber sheet containing fibers, the cement mortar panel and the fiber sheet being polymerized, and having at least the same shear strength and bending strength as the wall to be reinforced An underground concrete structure using panels,
A column that is different from the wall to be reinforced, and is anchored to a wall adjacent to the wall to be reinforced,
The reinforcing panel provided on the wall surface to be reinforced independently of the wall surface to be reinforced by being connected to the column,
An adhesive filling a gap between the reinforcing panel and the wall surface to be reinforced, and an adhesive that integrates the reinforcing panel and an underground concrete structure. Concrete structure. The underground concrete structure has the wall surface to be reinforced and a side wall perpendicular to the wall surface to be reinforced.
6. The underground concrete structure according to claim 5, wherein the support column is a wall surface different from the wall surface to be reinforced and anchored to the side wall as a wall surface adjacent to the wall surface to be reinforced. object. The underground concrete structure is a box culvert having the wall surface to be reinforced and a side wall orthogonal to the wall surface to be reinforced.
The wall surface to be reinforced of the box culvert is provided with a plurality of power transmission line inlets for drawing a power transmission line,
The support column is a wall surface different from the wall surface to be reinforced, and is anchored to the side wall as a wall surface adjacent to the wall surface to be reinforced,
  6. The underground concrete structure according to claim 5, wherein an end of the reinforcing panel and the support column are connected to the reinforcing panel.

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