JP6480672B2 - Concrete frame reinforcement method for water supply equipment - Google Patents

Description

  The present invention relates to a method for reinforcing a concrete frame such as a culvert, a dam bank, or a building.

  In order to increase the seismic strength of existing concrete structures, reinforcement methods have been carried out to improve the shear strength. In this reinforcement method, a drilling hole is formed in a concrete frame forming a concrete structure with a rotary tool such as a drill or a core boring machine, and a shear reinforcement member such as a reinforcing bar is inserted into the hole. A fixing material is filled in a gap between the inner wall surface of the drilling hole. The fixing material is closely packed so as not to form a cavity in the gap between the reinforcing bar and the inner wall surface of the drilling hole. Thereafter, the fixing material is cured, and the reinforcing bars are fixed to the concrete frame, whereby the shear strength of the concrete structure is improved.

  As this fixing material, non-shrinkable mortar (grout) is used because it is easily available and inexpensive. The non-shrink mortar is injected from the opening of the drilling hole toward the back after inserting the reinforcing bar into the drilling hole. At this time, if the fluidity of the mortar is not sufficient, or if the gap between the reinforcing bar and the inner wall surface of the drilling hole is very narrow, the non-shrinkable mortar may not reach the gap between the reinforcing bar and the inner wall surface of the drilling hole. was there. In Patent Document 1, a capsule containing a fluid curable resin such as an epoxy resin or a polyester resin is inserted into a drilling hole, and a shear reinforcement member is inserted into the drilling hole to crush the capsule to obtain a resin. A method is described in which a non-shrinking mortar is injected after the slag is caused to flow out so that no cavity is formed between the reinforcing bar and the inner wall surface of the hole.

JP 2003-113673 A

  It is necessary to reinforce the concrete frame so as to satisfy the shear strength shown in, for example, a concrete standard specification (Public Works Association). When the thickness of the concrete frame exceeds 2,000 mm, such as a dam wall, a long depth of drilling hole is formed so that the reinforcing bar has a fixed length that satisfies the standard (the length of the reinforcing bar embedded in the concrete). Must. In such a case, according to the method described in Patent Document 1, a capsule in which a resin is encapsulated in the back of a long hole so that the fixing material is filled to the details of the gap between the reinforcing bar and the inner wall surface of the hole. It was necessary to insert many. In addition, since a large amount of expensive resin is used compared to mortar, the material cost of concrete reinforcement work has been increased. Therefore, there has been a demand for a method that can reliably fill the gap between the reinforcing bar and the inner wall surface of the drilling hole without using an expensive resin for the fixing material.

  In addition, since the non-shrink mortar contains a large amount of aluminum oxide, the aluminum component is eluted into the water when it comes into contact with water after construction. Such fixing materials are stipulated in “Ministerial Ordinance Establishing Technical Standards for Water Supply Facilities” (Ministry of Health and Welfare Ordinance No. 15 on February 23, 2000: Ministry of Health, Labor and Welfare Ordinance No. 15 on February 28, 2014) Because it does not meet the water quality standards, it could not be used to reinforce waterworks facilities. Therefore, in order to satisfy this standard, it is necessary to coat the surface of the concrete frame with a mortar satisfying the water quality standard after filling with the fixing material, or to use a resin containing no aluminum component for the fixing material. This has led to an increase in the construction cost of concrete frame reinforcement and prolongs the construction period.

The present invention has been made to solve the above-mentioned problems. “Ministerial Ordinance for Establishing Technical Standards for Water Supply Facilities” (Ministry of Health and Welfare Ordinance No. 15 on February 23, 2000: final revision on February 28, 2014) Meets the standards of water purification equipment or water treatment equipment (water supply equipment, etc.) specified in the Ministry of Health, Labor and Welfare Ordinance No. 15). The purpose of the present invention is to provide a concrete frame reinforcement method for water supply equipment that can be filled with fixing material to every corner of the gap with the inner wall surface and can be constructed at a low cost in a short construction period.

Concrete skeleton Retrofit for water supply equipment of the present invention made in order to achieve the object (hereinafter, simply referred to as concrete skeleton Retrofit) from the surface of the concrete skeleton is a water supply equipment for supplying clean water it A step of forming a hole toward the center; an expansion material mainly composed of calcium oxide; and 3.4 to 6% by weight of aluminum oxide. The amount of the aluminum compound leached into the clean water is 0.00. The fixing material capsule absorbs the liquid by bringing the liquid into contact with the fixing material capsule in which a mortar which is a fixing material of less than 02 mg / L is sealed in a cylindrical container, and then the hole is removed from the fixing material capsule. And inserting the shear reinforcement member into the hole, and destroying the cylindrical container, so that the fixing material that has flowed out from the hole is removed from the inner wall of the hole Filling between the surface and the shear reinforcement member.

  In the concrete frame reinforcing method, the temperature of the liquid is preferably 40 ° C. at the maximum.

  In the concrete frame reinforcing method, the fixing material may be a mortar containing a cellulosic thickener.

  In the concrete frame reinforcing method, the mortar preferably contains 0.1 to 5.0% by weight of the cellulose-based thickener mainly composed of 2-hydroxypropyl methyl ether.

  In the concrete frame reinforcing method, the concrete frame may be water supply equipment.

  In the concrete frame reinforcing method, the depth of the hole may be 40 to 250 times the diameter of the reinforcing bar that is the shear reinforcing member.

  In the concrete frame reinforcing method, a plurality of the fixing material capsules may be inserted per one hole.

  The concrete frame reinforcing method may be formed in a horizontal direction.

  According to the concrete frame reinforcing method of the present invention, the gap between the inner wall surface of the drilling hole and the shear reinforcing material can be assured by simply inserting the shear reinforcement member into the drilling hole while crushing the fixing material capsule inserted into the drilling hole. Since it can be filled, the concrete frame reinforcement work can be carried out simply, quickly and inexpensively.

  When the fixing material used in the concrete frame reinforcing method is a mortar containing an expansion material mainly composed of calcium oxide and containing a maximum of 6% by weight of aluminum oxide, the reinforcing part comes into contact with water after construction. However, the amount of aluminum components eluted in the water is “Ministerial Ordinance for Establishing Technical Standards for Water Supply Facilities” (Ministry Ordinance No. 15 of the Ministry of Health and Welfare on February 23, 2000: Ordinance No. 15 of the Ministry of Health, Labor and Welfare on February 28, 2014) ), The concrete frame of waterworks equipment can be reinforced.

  The fixing material used in the concrete frame reinforcing method is a mortar containing 0.1 to 5.0% by weight of a thickener mainly composed of a cellulose-based thickener, for example, 2-hydroxypropyl methyl ether, When the shear reinforcement member is a reinforcing bar, even if it is a long hole having a depth of 40 to 250 times the nominal diameter of the reinforcing bar, the mortar is filled between the inner wall surface of the hole and the reinforcing bar without a gap, Does not cause poor filling.

It is a schematic cross section explaining one form of the concrete frame reinforcing method of the present invention. It is a schematic cross section of the waterworks equipment reinforced using the concrete frame reinforcement method of the present invention. It is a schematic cross section explaining another form of the concrete frame reinforcement method of this invention. It is a graph which shows the correlation of the temperature of the liquid which the fixing material capsule used for the concrete frame reinforcement method of this invention contacts, and the construction possible time of a fixing material capsule. It is a partially-omission side view which shows another form of the reinforcing bar used for the concrete frame reinforcement method of this invention. Aluminum oxide content of fixing material used in the concrete frame reinforcement method of the present invention and water supply equipment and materials-leaching test method JWWA Z 108: 2012 (Japan Water Works Association: "Test on materials of materials and equipment" ( It is a graph which shows the correlation with the leaching amount of the aluminum compound measured based on the prescription | regulation of 2000 Ministry of Health, Labor and Welfare notification No. 45).

  Hereinafter, although the form for implementing this invention is demonstrated in detail, the scope of the present invention is not limited to these forms.

  FIG. 1 shows a schematic cross-sectional view of one embodiment of the concrete frame reinforcing method of the present invention. The concrete frame 1 is an existing box culvert 20 used as a water supply equipment (see FIG. 2). The back surface 1 b of the concrete frame 1 is in contact with the ground 2. FIG. 1A shows a process of forming the hole 4. The core boring machine 3 is set on the surface 1a of the concrete casing 1, and the core drill 3a attached to the tip of the core boring machine 3 is rotated so that the drilling holes 4 are formed from the surface 1a of the concrete casing 1 toward the center thereof. Form. The hole 4 can be formed in a horizontal direction, a vertical direction, and an oblique direction.

  FIG. 1B shows a process of inserting the fixing material capsule 5 into the hole 4. In the fixing material capsule 5, a mortar 5a as a fixing material is sealed in a cylindrical container 5b. The mortar 5a is a so-called dry mortar that is not kneaded with water. Since the mortar 5a contains an expansion material mainly composed of calcium oxide, the contained aluminum oxide is suppressed to a very small amount. Specifically, the content of the expansion material is 1 to 10% by weight, and the content of the aluminum oxide is 6% by weight or less.

  The fixing material capsule 5 is immersed in the tray 7 containing the water 6 until the bubbles 6 a are not generated, and the water 6 that has entered through the cylindrical container 5 b is absorbed by the mortar 5 a in the fixing material capsule 5. Thereby, fluidity and viscosity are imparted to the mortar 5a. The fixing material capsule 5 is taken out from the water 6 and then inserted into the hole 4.

The cylindrical container 5b is formed of a non-woven fabric that does not easily break even when exposed to the water 6 and does not disperse the fibers in the water, and easily absorbs the water 6. An example of such a nonwoven fabric is a nonwoven fabric having a basis weight of 50 g / m ² or less. Paper such as Japanese paper may be used. Therefore, the mortar 5a enclosed in the cylindrical container 5b does not flow out into the water 6. Further, the cylindrical container 5b has a strength that can be handled by hand even when the fixing material capsule 5 is taken out of the water 6. The water 6 is preferably tap water because it can be easily obtained at the construction site.

  FIG. 1 (c) shows a step of inserting a shear reinforcement member into the hole 4 and filling the mortar 5 a between the reinforcing bar 8 and the inner wall surface of the hole 4. The reinforcing reinforcing bar 8 that is a shear reinforcing member has a base end that forms a surface substantially perpendicular to the central axis of the reinforcing bar 8 and a tip that forms a surface inclined by 45 degrees with respect to the base end surface. Yes. Thereby, the tip of the reinforcing reinforcing bar 8 is sharply pointed and easily breaks through the cylindrical container 5b. The total length of the reinforcing bar 8 is slightly shorter than the depth of the drilling hole 4 so that the fixing length of the reinforcing bar indicated in the standard can be satisfied.

  While striking the base end of the reinforcing steel bar 8 with a hammer drill 9, the reinforcing steel bar 8 is inserted into the drilling hole 4. The mortar 5a flows out into the hole 4 from the cylindrical container 5b pierced by the sharp tip of the reinforcing reinforcing bar 8. The reinforcing reinforcing bar 8 advances through the hole 4 while pushing away the mortar 5a. The hammer drill 9 is moved away from the base end of the reinforcing bar 8 when the tip of the reinforcing bar 8 hits the inner wall surface of the hole 4 and the base end of the reinforcing bar 8 is buried in the mortar 5a in the hole 4. The above operation is repeated for each drilling hole 4. Then, the reinforcement of the concrete housing 1 is completed when the mortar 5a is cured.

  FIG. 1 (d) shows a concrete frame 1 that has undergone the steps shown in FIGS. 1 (a) to (c). The hardened mortar 5 a closes the opening of the hole 4 and is closely packed between the inner wall surface of the hole 4 and the reinforcing reinforcing bar 8. The reinforcing reinforcing bars 8 are fixed to the concrete frame 1 by being inserted into the drilled holes 4 so as to three-dimensionally cross over the plurality of main reinforcing bars 11. In this way, the shear strength of the concrete frame 1 can be further improved by crossing the reinforcing bars.

Further, the length L ₁ from the base end of the reinforcing bar 8 to the surface 1a and the length L ₂ from the tip end of the reinforcing bar 8 to the back surface 1b are preferably 50 mm or more. According to it, the reinforcing bar 8 protrudes from the opening of the hole 4 to the surface of the concrete frame 1 due to the pressure on the uncured mortar 5a generated during the construction and the stress on the concrete frame 1 due to the shaking of the earthquake. In addition to preventing a problem that the concrete frame 1 penetrates the ground 2 through the concrete frame 1, the concrete frame 1 gives the reinforcing bar 8 a sufficient cover (the thickness of the concrete frame 1 covering the reinforcing bar 8). Rust prevention can be achieved. The concrete frame reinforcing method of the present invention is suitable for a concrete frame in which the distance between each main reinforcing bar 11 and the surface 1a and the back surface 1b of the concrete frame 1 is 50 mm or more so that the reinforcing bar 8 surely intersects with the main reinforcing bar 11. Used for. Note that the length L ₁ and L _2, may be different even in the same.

  FIG. 2 shows a schematic cross-sectional view of the box culvert 20 to which the concrete frame reinforcing method of the present invention is applied. The box culvert 20 is water supply equipment such as a water pipe through which the water 21 flows. A plurality of holes 4 are formed from the surface 1a of the concrete casing 1 of the box culvert 20 toward the back surface 1b in contact with the ground 2. Reinforcing bars 8 inserted into all of the hole 4 are fixed in the hole 4 by mortar 5a.

  Examples of the concrete casing 1 of the box culvert 20 include those having a thickness of 400 to 2000 mm. In this case, the reinforcing reinforcing bars 8 having a total length of 300 to 1800 mm and a diameter of 13 to 32 mm can be suitably used. In order to secure the fixing length of the reinforcing reinforcing bars 8, the hole 4 is preferably formed to a depth of 350 to 1900 mm and a diameter of 16 to 42 mm.

  The amount of aluminum compound leached into the water 21 from the mortar 5a having an aluminum oxide content of 6% by weight or less is “Ministerial Ordinance for Establishing Technical Standards for Water Supply Facilities” No. 15: The final revision does not exceed the water quality standards stipulated in the Ordinance No. 15 of the Ministry of Health, Labor and Welfare on February 28, 2014. Since the concrete frame reinforcing method of the present invention reinforces the water supply equipment using such a mortar 5a as a fixing material, aluminum of the fixing material does not leach after the fixing material is filled in the drilling holes. Thus, additional work such as coating is unnecessary on the surface of the concrete frame. Therefore, the construction period can be shortened. Furthermore, since the concrete frame reinforcing method uses an inexpensive mortar as the fixing material, the material cost of the reinforcing work can be reduced as compared with the case where a resin fixing material is used. As a result, it is possible to reinforce the concrete frame of water supply equipment at low cost.

  FIG. 3 shows another embodiment of the concrete frame reinforcing method according to the present invention. The concrete frame 1 of the dam dam body 30 shown in FIG. 3 (a) often has a thickness exceeding 2000 mm, and is much thicker than that of a culvert or a building. Therefore, a relatively thick and long reinforcing bar is used as the reinforcing reinforcing bar 8 in order to improve the shear strength. First, the process of forming the drilling hole 4 in this concrete housing 1 with the core boring machine 3 (refer FIG. 1 (a)) is performed. At this time, the drilling hole 4 is formed so that the depth M of the drilling hole 4 is 40 to 250 times the diameter N (see FIG. 3B) of the reinforcing reinforcing bar 8 inserted into the drilling hole 4. The diameter N is a nominal diameter of a reinforcing bar defined in JIS G 3112. Thereby, the fixing length of the reinforcing bar which can provide sufficient shear strength to the concrete frame 1 can be obtained. For example, when a reinforcing steel bar 8 having a concrete casing 1 having a thickness of 5000 mm and a diameter N of 19.1 to 50.8 mm (name: D19 to D51) is used, a drilling hole 4 having a depth M of 4600 mm. Is preferably formed. Thus, when reinforcing the concrete frame 1 of the dam dam body 30, an extremely long hole 4 is formed in order to improve the shear strength to a predetermined value.

  Next, as shown in FIG. 3 (b), a step of inserting a plurality of fixing material capsules 5 in which water 6 has been absorbed into the holes 4 is arranged. The fixing material capsules 5 may be sequentially inserted into the holes 4, or a predetermined number of fixing material capsules 5 may be connected in advance, and a series of fixing material capsules 5 may be inserted into the holes 4. Finally, the step of inserting the reinforcing bar 8 into the hole 4 and filling the mortar 5a between the inner wall surface of the hole 4 and the reinforcing bar 8 is performed.

  The flow-down value of the mortar 5a measured in accordance with the fluidity test method (J14 funnel test) of JIS C-F 541-2013 filled mortar specified in the concrete standard specification is 8 seconds or more, and conforms to JIS R 5201. The measured flow test value of the mortar 5a is 150 mm or more.

  Such a mortar 5a extends to every corner of the hole 4 even when the depth of the hole 4 is very long and the depth direction is horizontal to the ground. It has both the fluidity that allows the space between the reinforcing reinforcing bars 8 to be tightly packed and the viscosity that does not flow out of the opening of the hole 4. Therefore, according to the concrete frame reinforcing method of the present invention, as shown in FIG. 3 (c), the dam dam body does not leave a gap in the hole 4 or the mortar 5 a flows out from the hole 4. 30 can be reinforced.

  In order to obtain the desired flow-down value and flow test value, the mortar 5a may contain a thickener. A cellulose-based thickener containing a cellulose derivative such as cellulose ether is preferable as the thickener, and a cellulose-based thickener mainly composed of 2-hydroxypropyl ether is preferable. In this case, the content of the cellulose-based thickener mainly composed of 2-hydroxypropyl ether of the mortar 5a is preferably 0.1 to 5.0% by weight. Thereby, the mortar 5a which made fluidity | liquidity and viscosity compatible can be obtained.

  The time for immersing the fixing material capsule 5 in the water 6 and the temperature of the water 6 will be described. FIG. 4A shows the correlation between the immersion time (minutes) when the fixing material capsule 5 is immersed in water 6 at 20 ° C. and the weight fraction (% by weight) of the water 6 contained in the fixing material capsule 5. It is a graph. As shown in FIG. 6A, the fixing material capsule 5 absorbs water 6 rapidly until 2 minutes have passed since the start of immersion. During this time, water 6 enters the voids in the fixing material capsule 5. Since the water 6 pushes out the air accumulated in the gap, the pushed-out air is visually recognized from the outside as bubbles 6a (see FIG. 1C).

  After about 2 minutes from the start of the immersion, the weight of the water 6 in the fixing material capsule 5 is constant. Bubbles 6a are not generated. The operator can confirm that the fixing material capsule 5 has completely absorbed the water 6 by simply looking at the presence or absence of the bubbles 6a. The mortar 5a of the fixing material capsule 5 that has completed the absorption of the water 6 is gradually cured after maintaining the fluidity for a certain period of time. When the temperature of the water 6 is 20 ° C., the curing start time of the mortar 5a is about 20 minutes after the start of immersion. That is, it is necessary to insert the fixing material capsule 5 into the hole 4 and insert the reinforcing reinforcing bars 8 during the workable time T shown in FIG. When the workable time T elapses, the mortar 5a starts to harden and gradually loses its fluidity and viscosity, so that it becomes difficult for the mortar 5a to tightly fill the hole 4 into which the reinforcing steel bars 8 are inserted.

  The length of the workable time T is adjusted by the temperature of the water 6. FIG. 4B is a graph showing the correlation between the temperature (° C.) of the water 6 and the workable time T (minutes). The higher the temperature of the water 6, the shorter the construction possible time T. In particular, when the temperature is 40 ° C. or more, the construction possible time T is as short as 10 minutes or less, so that the construction becomes difficult. On the other hand, when the temperature of the water 6 is low, the workable time T becomes long. However, the time until the mortar 5a is cured becomes excessive, and the possibility that the mortar 5a flows out from the opening of the hole 4 increases. From this, the temperature of the water 6 is preferably 10 to 35 ° C, and more preferably 15 to 25 ° C.

  The water 6 may be absorbed by the mortar 5a by spraying the water 6 on the fixing material capsule 5. Moreover, the material of the cylindrical container 5b should just be a thing which does not tear easily even if exposed to the water 6, and permeate | transmits the water 6, for example, can mention the woven fabric or nonwoven fabric of a cellulose or polyolefin.

  FIG. 5 shows a partially omitted side view of another form of the reinforcing reinforcing bar 8. A hemispherical end 8a that protrudes in the extending direction of the central axis XX of the reinforcing reinforcing bar 8 and has a hemispherical shape whose diameter is larger than that of the body 8b is formed at both ends of the reinforcing reinforcing bar 8 shown in FIG. Has been. The reinforcing reinforcing bar 8 has a step surface 8c facing each other between the hemispherical end portion 8a and the trunk portion 8b.

  When the reinforcing reinforcing bar 8 is inserted into the hole 4 and the fixing material capsule 5 is broken by the hemispherical end portion 8a, and the mortar 5a is filled in the hole 4, the mortar 5a comes into close contact with the stepped surface 8c. Meanwhile, the reinforcing reinforcing bars 8 are fixed in the hole 4. As a result, an anchor effect appears between the step surface 8c and the mortar 5a. This reinforcing rebar 8 has a high pulling resistance (force that resists the force applied in the direction of pulling out the rebar from the concrete frame) compared to the reinforcing rebar without the hemispherical end 8a due to the anchor effect. Even if a shearing force is generated in the concrete frame 1 due to the earthquake and the reinforcing bar 8 receives a force in a direction in which the reinforcing bar 8 is pulled out from the concrete frame 1, the reinforcing bar 8 is not easily pulled out. Therefore, the concrete frame reinforcing method using the reinforcing reinforcing bars 8 shown in FIG. 5 has the same nominal diameter as that of the reinforcing reinforcing bar 8 without the hemispherical end portion 8a, and the number of reinforcing reinforcing bars 8 is reduced. Even if a thinner reinforcing bar 8 is used, a high shear strength can be imparted to the concrete frame 1. As a result, the material cost is reduced, and the concrete frame can be reinforced at low cost. Moreover, since the thin reinforcing steel bar 8 can reduce the possibility of interfering with the existing main reinforcing bar 11 during construction, it is excellent in workability. Therefore, since it can construct smoothly, the construction period of concrete frame reinforcement can be shortened.

  FIG. 5 shows an example in which the hemispherical end portion 8 a is formed at both ends of the reinforcing reinforcing bar 8, but the hemispherical end portion 8 a may be formed only at one end portion of the reinforcing reinforcing bar 8. Further, the hemispherical end 8a can be formed by forging, particularly forging.

  Examples of the shear reinforcing member include a steel rod, a metal rod such as a cut bolt, or a resin rod reinforced with carbon fiber or aramid fiber in addition to the reinforcing bar.

  Below, the Example which applied the concrete frame reinforcement method of this invention and the comparative example which does not apply this invention are shown.

(Example)
A mortar as a fixing material used in the concrete frame reinforcing method of the present invention was prepared. First, 58 kg of early strength Portland cement (manufactured by Ube Mitsubishi Cement Co., Ltd.), 2 kg of mortar expansion material (product name: Taiheiyo Hyper Expan Co., Ltd., manufactured by Taiheiyo Materials Co., Ltd.) whose main component is calcium oxide, and 2-hydroxy main component 1kg of mortar thickener (product name: Asuka Clean) manufactured by Shin-Etsu Chemical Co., Ltd., which is propyl methyl ether, and 1kg of mortar thickener (product name: Aerosil manufactured by Nippon Aerosil Co., Ltd.) whose main component is silica fine particles. Was added. Further, 30 kg of silica sand, 3 kg of gypsum, 4 kg of silica fume and 1 kg of additives were added to obtain 100 kg of the mortar of the example.

(Comparative Example 1)
A mortar of Comparative Example 1 was obtained in the same manner as in the Example except that the mortar thickener was not added.

(Comparative Example 2)
A mortar of Comparative Example 2 was obtained in the same manner as in the Example except that the mortar thickener was changed to 6% by weight.

(Comparative Example 3)
A mortar of Comparative Example 3 was obtained in the same manner as in the Example except that the mortar thickener was changed to 12% by weight.

(Leaching test)
About the mortar of an Example and Comparative Examples 1-3, the content rate of aluminum oxide is calculated | required based on the determination method of the aluminum oxide prescribed | regulated to JISR5202, and also water supply equipment-leaching test method JWWA Z 108: 2012. The leaching test was conducted in accordance with (Japan Water Works Association: “Testing on Materials of Materials and Equipment” (specified by Ministry of Health, Labor and Welfare Notification No. 45)). The results are shown in FIG. The figure is a graph showing the correlation between the aluminum oxide content (% by weight) and the aluminum compound leaching amount (mg / L). As is clear from FIG. 6, the mortar of the example is “Ministerial Ordinance for Establishing Technical Standards for Water Supply Facilities” (Ministry of Health, Labor and Welfare No. 15 February 23, 2000: Final revision February 28, 2014, Ministry of Health, Labor and Welfare) Since it is far below 0.02mg / L, which is the standard of Ordinance No.15), it can be used for concrete frame reinforcement for waterworks equipment. The mortar of Comparative Example 1 shows almost the same value as the standard. Since the mortars of Comparative Examples 2 and 3 greatly exceed the standard, they cannot be used to reinforce the concrete frame of waterworks equipment.

(J14 funnel test and flow test)
30% by weight of tap water was added to each of the mortars of Examples and Comparative Examples 1 to 3. Subsequently, the J14 funnel test prescribed | regulated to JSCE-F 541-2013 and the flow test prescribed | regulated to JISR5201 were done.

(Long construction test)
The mortars of Examples and Comparative Examples 1 to 3 were each filled into a tubular container (diameter: 24 mm, length: 300 mm) of a nonwoven fabric (weight per unit: 0.4 g / m ² ) with one end opened, and the opening was closed to fixer capsule Was made. The fixing material capsule was immersed in tap water at 20 ° C. for 2 minutes. A drilling hole having a depth of 4600 mm, a diameter of 28 mm, and a depth direction parallel to the ground was formed in a concrete frame having a thickness of 5000 mm. A necessary number of fixing material capsules were inserted into the hole, and a deformed steel bar D19 (nominal diameter 19.1 mm) as a shear reinforcing member was inserted.

  Table 1 shows the results of the J14 funnel test, flow test, and long construction test.

  In Table 1, “rebar insertion / possibility” was indicated as “◯” when smooth construction was possible, “Δ” when construction was possible but time-consuming, and “x” when construction was impossible. About "hole filling", it confirmed visually from the opening of the hole. The case where no gap was observed between the reinforcing bar and the inner wall surface of the drilled hole was indicated as ◯, and the case where the gap was observed was indicated as ×. Since the comparative example 3 was not able to insert a reinforcing bar, it was not evaluated. As for “determination”, if the rebar insertability and hole filling are both ◯, good, the rebar insertion possibility is △ and the hole filling is ◯, either rebar insertion is possible or hole filling On the other hand, those with x were not allowed.

  As is clear from Table 1, the concrete frame reinforcement method using the mortar of the example can be suitably used for reinforcing a very thick concrete frame such as a dam dam body and a concrete frame of waterworks equipment. .

  The concrete frame reinforcing method of the present invention is used to reinforce concrete frames such as waterworks equipment and dam dams.

1 is a concrete frame, 1a is a surface, 1b is a back surface, 2 is the ground, 3 is a core boring machine, 3a is a core drill, 4 is a drilling hole, 5 is a fixing material capsule, 5a is a mortar, 5b is a cylindrical container, 6 is Water, 6a bubbles, 7 tray, 8 reinforcing steel bar, 8a hemispherical end, 8b trunk, 8c stepped surface, 9 hammer drill, 11 main reinforcing bar, 20 box culvert, 21 water supply , 30 is a dam body, L ₁ and L ₂ are lengths, M is a depth, N is a diameter, T is a workable time, and X is a central axis.

Claims (7)

Forming a drilling hole from the surface of the concrete frame, which is a water supply equipment for flowing water , toward the center of the concrete frame;
Mortar which is a fixing material containing an expansion material mainly composed of calcium oxide and 3.4 to 6% by weight of aluminum oxide and whose amount of aluminum compound leached into the clean water is less than 0.02 mg / L is cylindrical. A step of causing the fixing material to absorb the liquid by bringing the liquid into contact with a fixing material capsule sealed in a container, and then inserting the fixing material capsule into the hole;
Filling the gap between the inner wall surface of the drilling hole and the shear reinforcement member by inserting a shear reinforcement member into the drilling hole and destroying the cylindrical container,
A concrete frame reinforcement method for water supply equipment characterized by having. The concrete body reinforcement method for waterworks equipment according to claim 1, wherein the temperature of the liquid is 40 ° C at the maximum. The concrete frame reinforcing method for waterworks equipment according to claim 1, wherein the fixing material is a mortar containing a cellulosic thickener. The mortar, for water supply equipment according to claim 3, characterized by containing 0.1 to 5.0% by weight of the cellulose-based thickener mainly comprising 2-hydroxypropyl methyl ether the concrete skeleton Retrofit for. The depth of the said drilling hole is 40 to 250 times the diameter of the reinforcing bar which is the said shear reinforcement member, The concrete frame reinforcement construction method for waterworks equipments of Claim 1 characterized by the above-mentioned. The concrete frame reinforcing method for waterworks equipment according to claim 1, wherein a plurality of the fixing material capsules are inserted per one hole. 2. The concrete frame reinforcing method for waterworks equipment according to claim 1, wherein the hole is formed in a horizontal direction.

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