JP2018096082A - Reinforcement construction method and reinforcement structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reinforcement construction method and a reinforcement structure with simple and little work burden of construction, suppressing the extension of cracks etc. happened in steel members of a steel structure, and restoring the strength degradation by the section decrease occurred by cracks and corrosion.SOLUTION: The reinforcement construction method for reinforcing a partially damaged steel structure 8, comprises: a removing process of removing a surface treatment 4 from a steel member 2 used for the steel structure 8; and a coating process of applying a fiber reinforced paste 5 to a surface 20 of the steel member 2. In the removing process, the steel member 2 is exposed by removing the plating or painting provided as the surface treatment 4 of the steel member 2 around a defect portion 3 where the steel member 2 is partially damaged. In the coating process, the fiber reinforced paste 5 is applied so as to cover the defect portion 3 in an exposure range R1 where the surface treatment 4 is removed and the steel member 2 is exposed.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a reinforcing method and a reinforcing structure for reinforcing a partially deficient steel structure.

  In recent years, there has been concern over the aging of infrastructure such as buildings that were built during the period of high economic growth in Japan and have been in operation for more than 50 years. However, many of these buildings may carry infrastructure, and in many cases, construction such as easy rebuilding or demolition or full-scale repair and reinforcement by stopping the infrastructure function is not possible. For these buildings, it is required to provide materials that can be easily repaired and reinforced, and have sufficient functions, and are usually repaired with cement, repaired with a resin composition, or even at the work site. Materials such as fiber reinforced prepregs that can be pasted are proposed and used.

  Repair work using cement is mainly considered for civil engineering construction using concrete. However, since cement has a problem of adhesion to the groundwork, when it is applied vertically or when it is applied to the ceiling, it is necessary to install ancillary accessories such as reinforcing bars and wire nets to adhere the cement separately. There is a problem that it is necessary and construction is complicated (for example, Non-Patent Document 1).

  In order to solve this problem, a method has been developed in which a resin is directly injected into a generated crack portion to close the crack (for example, Patent Document 1 and Non-Patent Document 2). However, in order to infiltrate the resin into fine cracks, a high-pressure injection method is required at the work site, and a resin with a low viscosity and good flow is required. A countermeasure cannot be taken, and a reinforcing effect cannot be obtained simply by filling a crack hole. In addition, this repair method is mainly intended for concrete and is not necessarily a preferable method for repairing steel structures and the like.

  Furthermore, in order to overcome the above problems, recently, a repair method has been developed in which a fiber-reinforced prepreg is attached to the surface of a building structure to maintain rigidity (for example, Non-Patent Document 3). This method is an application of a construction method (for example, Non-Patent Document 4) for the purpose of suppressing crack growth that has conventionally occurred on the tail of an aircraft, etc., to the field of construction and civil engineering. It is assumed that the effect of suppressing the growth of a crack generated in the structural member can be obtained by pasting (for example, Non-Patent Document 5). However, unlike an aircraft tail, etc., the structure of a building is not necessarily flat, but there are irregularities and ribs, so the prepreg application method for attaching a large sheet at the work site is not necessarily the preferred method. Absent.

  The disclosed technology of Patent Document 2 tries to overcome the problems of the prepreg application method by processing and attaching the fiber-reinforced prepreg sheet in accordance with the shape of the steel structure and the state of the generated crack. It is a thing. However, detailed work at the work site is not necessarily a preferable measure in terms of cost and safety. In addition, these methods need to use a preferred adhesive when a fiber-reinforced prepreg is attached to the base, and depending on the selection of this adhesive, the fiber-reinforced prepreg may be peeled off after application, Problems such as inability to obtain a crack growth suppression effect have occurred.

  In addition, in the disclosed technologies of Patent Document 3 and Patent Document 4, it is attempted to suppress crack propagation by adding a nanofiller to the resin so that the filler penetrates into the crack to solve such problems. However, it has not been fully verified how much crack suppression effect can be obtained by penetration of the nanofiller into the crack.

  Further, in the disclosed technique of Patent Document 5, a spray-type repair material is proposed in which the rigidity of the steel structure and the mortar layer is approximately equal to the shearing force by adjusting the polymer cement ratio. However, the spray type repair material of Patent Document 5 uses a brittle material called cement, even if it is possible to obtain rigidity. For example, in a building such as a steel bridge that is constantly exposed to vibration or the like, the spray material is used. It has elements that are not necessarily sufficient in terms of its own strength and adhesive strength between the spray material and the steel structure that requires reinforcement.

  Further, in the disclosure techniques of Patent Document 6 and Patent Document 7, a method is proposed in which a composite material system in which a fibrous filler is added to a thermosetting resin is used to reinforce a building outer wall or a building foundation by coating. Yes. However, in this method, depending on the orientation of the fibrous filler, not only the strength and the elastic modulus are deflected, but there is a possibility that a balanced reinforcing effect cannot always be obtained for the target building. The glass fiber or rock wool fiber proposed in the method has a high specific gravity because it is an inorganic filler, for example, when it is applied perpendicularly to the outer wall with a thickness, etc. Problems in terms of workability are likely to occur, and there are problems that are not necessarily sufficient.

JP 2004-263048 A JP 2006-57352 A JP 2011-62809 A JP 2005-28462 A JP 2012-184575 A JP 2003-213136 A JP 2003-213938 A

Fukuda et al., Tunnel Engineering Report, Vol. 15, p29 (2006) Nippon Steel & Sumikin Cement Co., Ltd. Special Product Guide, June 2013 Ishikawa, Journal of the Adhesion Society of Japan, 45, p139 (2009) M.M. Sato et al. Adv. Comp. Mater. , 11 (1), p51-59 (2002) Matsumoto et al., Structural Engineering Papers, VOL. 59A, p798 (2013)

  As described above, temporary cracks due to the application of cementitious materials, the injection of the resin composition into the cracked part, or the application of a sheet-like prepreg, etc., to fatigue cracks occurring in steel structures Although there are examples of research aimed at suppressing the growth, there are no examples that have achieved a significant suppression and improvement of crack propagation with practicality by a construction method that is simple and less burdensome during construction. For this reason, there is a need for a simple construction method and a coating type reinforcement method and a reinforcement structure that realize mechanical properties that cannot be realized by conventional cements, polymer cements, resin compositions, or fiber reinforced prepregs. Here, coating refers to applying a repair material at various work sites.

  Therefore, the present invention has been devised in view of the above-described problems, and its object is to suppress the development of cracks and the like generated in the steel material of a steel structure, and to prevent cracks and corrosion. In order to recover the strength reduction caused by the reduction in the cross-section caused by the above, it is to provide a simple and simple reinforcing method and a reinforcing structure with less work load during construction.

  The reinforcing method according to the first invention is a reinforcing method for reinforcing a partially deficient steel structure, a removing step of removing surface treatment from the steel material used for the steel structure, and the surface of the steel material. An application step of applying a fiber reinforced paste to the steel sheet, and in the removing step, the plating or coating provided as a surface treatment of the steel material is removed around a defect portion where the steel material is partially lost. The steel material is exposed, and in the application step, the fiber reinforced paste is applied so as to cover the defect in an exposed range where the surface treatment is removed and the steel material is exposed.

  The reinforcing method according to a second aspect of the present invention is the covering range in which the surface treatment of the steel material is not removed in a portion substantially orthogonal to the direction of the main stress acting on the steel structure in the coating step in the first aspect. Is characterized in that the fiber reinforced paste is applied only to the exposed range without applying the fiber reinforced paste.

  In the reinforcing method according to the third invention, in the second invention, in the application step, the anticorrosion treatment is performed by providing an anticorrosive material in the exposed range between the application range where the fiber reinforced paste is applied and the coating range. It is characterized by giving.

  In any one of the first to third inventions, the reinforcing method according to the fourth invention is that, in the application step, an anticorrosive material is provided on substantially the entire surface of the fiber reinforced paste in the application range where the fiber reinforced paste is applied. It is characterized by applying anticorrosion treatment.

  The reinforcing method according to a fifth aspect of the present invention is the reinforcement method according to any one of the first to fourth aspects of the present invention, wherein, in the removing step, the steel material is cracked in an end portion of the defect portion, and the steel material has the defect portion. A stop hole that suppresses the progress of the crack is formed.

  A reinforcing method according to a sixth aspect of the present invention is the method according to any one of the first aspect to the fifth aspect, wherein in the coating step, the fiber reinforced paste is placed between the steel material and the surface of the steel material in the coating range where the fiber reinforced paste is coated. A reinforcing material is provided so as to be sandwiched.

  In any one of the first to sixth inventions, the reinforcing method according to a seventh aspect of the present invention is such that, in the application step, a transparent plate is provided so as to cover an end portion of the defective portion in which the steel material is cracked. The fiber reinforced paste is applied so as to surround the transparent plate.

  In any one of the first to seventh inventions, the reinforcing method according to the eighth invention is that, in the application step, the fiber-reinforced paste is applied over substantially the entire circumference of the partially lost steel structure. Features.

  In the reinforcing method according to a ninth aspect of the present invention, in any one of the first to eighth aspects, a resin composition containing a room temperature curable thermosetting resin and a filler is used as the fiber reinforced paste in the coating step. The resin composition contains both a fibrous filler and a non-spherical particle filler as the filler, has a viscosity of 5 to 2000 Pa · s at 25 ° C., and 100 wt. The fiber filler and the non-spherical particle filler are contained in a total amount of 20 to 150 parts by weight with respect to the part in a blending ratio of the following formula (1), and the average particle diameter of the non-spherical particle filler is 1 to 80 μm. To do.

  Blending amount of non-spherical particle filler / blending amount of fibrous filler = 1 to 10 (1)

  A reinforcing structure according to a tenth invention is a reinforcing structure for reinforcing a partially deficient steel structure, comprising a fiber reinforced paste applied to the surface of a steel material used in the steel structure, the fiber The reinforcing paste covers the defect portion in an exposed range where the steel material is exposed by removing the plating or coating provided as a surface treatment of the steel material around the defect portion where the steel material is partially missing. It is characterized by being applied.

  According to 1st invention-10th invention, since stress transmission is made through the fiber reinforced paste applied so that the defect | deletion part of steel materials may be covered, it is a case where the partial defect | deletion arises in the steel materials of a steel structure, In addition, the steel structure can be sufficiently reinforced. In addition, it mainly applies fiber-reinforced paste, and can easily reinforce and repair the missing part of the steel, reducing the work burden during construction and suppressing the development of cracks, etc., in the steel of the steel structure. In addition, it is possible to recover the strength reduction due to the reduction in the cross section caused by cracks, corrosion, and the like.

  In particular, according to the second invention, the fiber-reinforced paste is applied only to the exposed range of the steel material without applying the fiber-reinforced paste to the covered range of the steel material, so that the adhesive surface of the fiber-reinforced paste is hardly peeled off. Thus, the reinforcing effect of the fiber reinforced paste can be improved.

  In particular, according to the third invention, the fiber reinforced paste is applied only to the exposed range of the steel material, so that a gap in which the steel material is exposed is generated between the applied range of the fiber reinforced paste and the coated range of the steel material. Even in such a case, it is possible to prevent the steel material from being corroded by electric corrosion or the like by providing a corrosion protection material in the gap where the steel material is exposed and performing the anticorrosion treatment.

  In particular, according to the fourth invention, the fiber reinforced paste after coating is completely cured by providing the anticorrosive material on almost the entire surface of the fiber reinforced paste including the gap in the exposed range of the steel material and applying the anticorrosion treatment. It is possible to prevent deterioration due to moisture absorption of the fiber reinforced paste, which may occur when the humidity suddenly increases due to previous rainfall or the like, and at the same time, it is possible to prevent the steel material from being corroded by electrolytic corrosion or the like. Furthermore, it becomes easier to secure an appropriate thickness of the fiber reinforced paste by molding the fiber reinforced paste before curing from an anticorrosive material such as a sealing waterproof tape.

  In particular, according to the fifth aspect, even when the steel material is cracked and the end of the defect is sharp, a stop hole is formed at the end of the defect of the steel, and the end of the defect By relaxing the stress concentration at the part, it is possible to suppress the growth of cracks.

  In particular, according to the sixth invention, a reinforcing material such as a steel plate is provided so that the fiber reinforced paste is sandwiched between the surface of the steel material, and stress is transmitted to the reinforcing material bonded to the fiber reinforced paste. Thus, the reinforcing effect on the steel structure can be improved. In addition, even if the stress is transmitted to the reinforcing material and the thickness of the fiber reinforced paste applied is reduced, the fiber reinforced paste and the reinforcing material are combined together to obtain a sufficient reinforcing effect. By reducing the thickness, it is possible to improve the strength per unit thickness of the fiber reinforced paste and efficiently improve the reinforcing effect while suppressing the amount of the fiber reinforced paste used.

  In particular, according to the seventh invention, a transparent plate is provided so as to cover the end portion of the defect portion where the steel material is cracked, and a fiber-reinforced paste is applied so as to surround the transparent plate without covering it, By ensuring the visibility by the transparent plate at the end of the defect part, it becomes possible to follow the crack condition at the end part of the defect part. In addition, since the fiber reinforced paste is applied so as to surround the transparent plate, it is possible to accurately apply the thickness of the fiber reinforced paste applied by simple operation only in accordance with the thickness of the transparent plate. .

  In particular, according to the eighth aspect of the present invention, the fiber reinforced paste is applied only over the entire circumference of the steel structure, instead of applying the fiber reinforced paste only around the defect portion that becomes a part of the steel structure. By wrapping the structure, not only the adhesion force of the fiber reinforced paste, but also the stress transmission to the fiber reinforced paste is made by the supporting pressure, and it becomes possible to increase the load carrying capacity and prevent the adhesion breakage, It is possible to greatly reduce the risk in the case of the adhesion failure.

  In particular, according to the ninth invention, by using a predetermined resin composition containing a room temperature curable thermosetting resin and a filler as a fiber reinforced paste, a method of reducing the work load at the time of construction can be used to reduce defects in the steel material. Crack propagation and the like can be suppressed. In addition, by changing the thickness and shape of the application of the fiber reinforced paste in various ways to realize a flexible design of the cross-sectional area and bonding area of the reinforcing part, various types of defects in various types of steel materials can be obtained. It can be reinforced.

It is a perspective view which shows the illumination pillar used as the object of the reinforcement structure and reinforcement method to which this invention is applied. It is a perspective view which shows the defect | deletion part of the steel materials used for the steel structure used as the object of the reinforcement structure and reinforcement method to which this invention is applied. (A) is a longitudinal cross-sectional view which shows the defect | deletion part defect | deleted so that steel materials may penetrate, (b) is a longitudinal cross-sectional view which shows the defect | deletion part in which a part of plate | board thickness of steel material was defect | deleted. (A) is a longitudinal cross-sectional view which shows the surface treatment before a steel material lose | deletes, (b) is a longitudinal cross-sectional view which shows the surface treatment after a steel material lose | deletes. It is a front view which shows the reinforcement structure to which this invention is applied. It is a longitudinal cross-sectional view which shows the removal process of the reinforcement construction method to which this invention is applied. (A) is a front view which shows the edge part of the defect | deletion part which the steel materials lost | missed in the crack shape, (b) is a front view which shows the stop hole which suppresses the progress of the crack. It is a longitudinal cross-sectional view which shows the application | coating process of the reinforcement construction method to which this invention is applied. (A) is a front view which shows the reinforcing material of the steel plate provided so that a fiber reinforced paste may be inserted | pinched, (b) is the AA line cross-sectional view. (A) is a front view which shows the reinforcing material of the reinforcing bar provided so that a fiber reinforced paste may be inserted | pinched, (b), (c) is the AA line cross-sectional view. It is a front view which shows the transparent plate provided so that the steel material might cover the edge part of the defect | deletion part missing | missed in the shape of a crack. It is a longitudinal cross-sectional view which shows the state by which stress transmission is made through the fiber reinforced paste after hardening by the reinforcement structure and reinforcement construction method to which this invention is applied. (A) is a longitudinal cross-sectional view which shows the state which has not apply | coated the fiber reinforcement paste to the coating range of steel materials with the reinforcement structure and reinforcement construction method to which this invention is applied, (b) is a fiber in the coating range of steel materials. It is a longitudinal cross-sectional view which shows the state by which the reinforcement | strengthening paste was apply | coated. (A) is a longitudinal cross-sectional view which shows the state by which stress transmission is made through the fiber reinforced paste and reinforcing material after hardening by the reinforcement structure and reinforcement construction method to which this invention is applied, (b) is the fiber reinforced paste. It is a longitudinal cross-sectional view which shows the state made thin. It is a front view which shows the action direction of the main stress of the steel structure used as the object of the reinforcement structure and reinforcement method to which this invention is applied. It is a perspective view which shows the state by which the fiber reinforcement paste was apply | coated over the perimeter of the steel structure by the reinforcement structure and reinforcement method to which this invention is applied. It is a longitudinal cross-sectional view which shows the state by which the visibility by the transparent plate was ensured by the edge part of the defect | deletion part of steel materials with the reinforcement structure and reinforcement method to which this invention is applied. (A) is a front view which shows the test body in the tensile test of the reinforcement structure and reinforcement construction method to which this invention is applied, (b) is the side view. It is a graph which shows the relationship between the load of each test body and the displacement in the tensile test of the reinforcement structure and reinforcement method to which this invention is applied. It is a graph which shows the relationship between the maximum load of each test body and the average thickness of a test body in the tensile test of the reinforcement structure and reinforcement method to which this invention is applied. It is a front view which shows the test body in the fatigue test of the reinforcement structure and reinforcement method to which this invention is applied. It is a front view which shows the steel pipe used as the object of the reinforcement structure and reinforcement method to which this invention is applied. It is a front view which shows the anchor installed in the vicinity of a steel pipe by the reinforcement structure and reinforcement method to which this invention is applied. It is a front view which shows the steel pipe for coating | cover provided so that the circumference | surroundings of a steel pipe may be surrounded by the reinforcement structure and reinforcement construction method to which this invention is applied.

  Hereinafter, the form for implementing the reinforcement structure 1 and the reinforcement construction method to which this invention is applied is demonstrated in detail, referring drawings.

  As shown in FIG. 1, the reinforcing structure 1 and the reinforcing method to which the present invention is applied are partially applied to a steel structure 8 in which a steel material 2 such as an illumination column or a sign column is used, due to deterioration over time. Used to reinforce the missing steel structure 8.

  The reinforcing structure 1 and the reinforcing method to which the present invention is applied are mainly used for reinforcing an existing steel structure 8. In addition, the reinforcing structure 1 and the reinforcing method to which the present invention is applied are used to reinforce the steel structure 8 such as a lighting column or a sign column, and any steel material 2 such as a shape steel, a steel pipe, a thin plate or a thick plate can be used. It may be used to reinforce the steel structure 8 used.

  The steel structure 8 is, for example, a base 8a to which a lighting column or the like is connected to the ground, or an opening 8b for maintaining and managing the lighting equipment, and the like, and the steel material 2 used for the steel structure 8 is fatigue cracked. Etc. may occur. At this time, as shown in FIG. 2, the steel structure 8 such as an illumination column causes the steel material 2 to be partially lost due to the occurrence of fatigue cracks or the like in the steel material 2, thereby forming the defect portion 3.

  The defect portion 3 is formed by generating a fatigue crack at a location where the stress of the steel material 2 is concentrated, such as the vicinity of the toe where the rib 81 is rotated by the base portion 8a such as an illumination column and joined by welding. As shown in FIG. 3 (a), the defect portion 3 is formed not only by the occurrence of a fatigue crack but also by the defect that the steel material 2 penetrates due to an external impact force or the like. . Moreover, the defect | deletion part 3 may be formed when a part of board | plate thickness of the steel material 2 is defect | deleted by corrosion etc. of a metal, as shown in FIG.3 (b).

  The steel material 2 used for the steel structure 8 is provided with plating or coating as the surface treatment 4 of the steel material 2 as shown in FIG. 4A for the purpose of preventing corrosion due to rainwater and the like and improving aesthetics. . At this time, the surface 20 of the steel material 2 is covered with a plating layer such as galvanizing or the like, and is covered with a general anticorrosion coating or the like, and the steel material 2 is subjected to the surface treatment 4.

  As shown in FIG. 4 (b), the steel material 2 used for the steel structure 8 is partially lost due to the occurrence of fatigue cracks or the like, with the surface treatment 4 applied to the steel material 2. As a result, the defect 3 is formed. At this time, the surface 20 of the steel material 2 is in a state where plating or coating is provided as the surface treatment 4 of the steel material 2 even around the defect 3 where the steel material 2 is partially lost.

  As shown in FIG. 5, the reinforcing structure 1 to which the present invention is applied includes a fiber reinforced paste 5 applied to the surface 20 of the steel material 2 used in the steel structure 8. And the reinforcement structure 1 to which this invention is applied passes the reinforcement construction method to which this invention is applied, removes the plating or coating provided as the surface treatment 4 of the steel material 2 around the defect | deletion part 3 of the steel material 2, and removes the steel material 2 The fiber reinforced paste 5 is applied so as to cover the defect portion 3 in the exposed range R1 in which is exposed.

  As shown in FIGS. 6 to 8, the reinforcing method to which the present invention is applied includes a removal step of removing the surface treatment 4 from the steel material 2 used in the steel structure 8, and a fiber reinforced paste 5 on the surface 20 of the steel material 2. In particular, it is carried out from a state in which the surface treatment 4 is applied to the steel material 2.

  First, in the removal step, as shown in FIG. 6A, by using a shot blast or a disk grinder 40 or the like, a surface treatment is performed on the surface 20 of the steel material 2 around the defect portion 3 of the steel material 2, The plating or coating provided as the surface treatment 4 of the steel material 2 is removed.

  In the removal step, as shown in FIG. 6B, the plating or coating provided as the surface treatment 4 of the steel material 2 is removed around the defect portion 3 of the steel material 2 to be used for the steel structure 8. Exposed steel material 2 is exposed. At this time, as for the steel material 2 used for the steel structure 8, the range which removed the surface treatment 4 of the steel material 2 and exposed the steel material 2 becomes the exposure range R1, and the surface treatment 4 of the steel material 2 is removed. The non-covered range is the coating range R2 coated with plating or painting.

  Here, when removing the surface treatment 4, it is ideal that it is desirably completely removed in the entire exposure range R <b> 1, but this is impossible in practice, and it is also very easy to confirm. Have difficulty. For example, “Ryuichi Yokota, Ken Fujii, Kouichi Horii, Junya Hidekuma“ Effect of residual rust on partial strength recovery of corroded steel sheet using adhesives ” In I-439, 2016 ", it has been confirmed in an experiment of an adhesive bonded joint that if 75% of the surface treatment of the bonded surface is removed, there is no change in yield strength as a joint. For this reason, it is sufficient if it can be visually confirmed that the surface treatment 4 in the exposure range R1 is almost removed, and the fine spot-like surface treatment 4 remains on the edge of the weld bead that is difficult to remove. Even if it is a case, it can be regarded as what the plating or coating provided as the surface treatment 4 was removed.

  As shown in FIG. 7 (a), the steel material 2 used in the steel structure 8 is broken like a crack due to the occurrence of a fatigue crack or the like, so that one or both end portions 3a of the broken portion 3 are formed. It may be sharply formed. At this time, in the removing step, the steel material 2 is cut into a substantially circular arc shape or the like as shown in FIG. Thus, the stop hole 30 that suppresses the progress of the crack of the defect portion 3 may be formed in the steel material 2.

  Next, in the coating process, as shown in FIG. 8A, fiber reinforcement is performed so as to cover the defect portion 3 of the steel material 2 in the exposed range R1 where the surface treatment 4 of the steel material 2 is removed and the steel material 2 is exposed. Paste 5 is applied. At this time, the steel material 2 used for the steel structure 8 removes the surface treatment 4 and exposes the steel material 2 so as to partially or entirely cover the defective portion 3 of the steel material 2. The range in which the fiber reinforced paste 5 is applied is the application range R3.

  Here, in the coating step, the fiber reinforced paste 5 is applied only to the exposed range R1 where the steel material 2 is exposed without applying the fiber reinforced paste 5 to the coating range R2 where the surface treatment 4 of the steel material 2 is not removed. It is desirable to apply. At this time, the steel material 2 used for the steel structure 8 is separated from or brought into contact with the surface treatment 4 of the coating range R2 so as not to overlap with the surface treatment 4 of the steel material 2 of the coating range R2. The fiber reinforced paste 5 is applied to the surface 20 of the substrate.

  Finally, in the application step, as shown in FIG. 8 (b), an application range R3 in which the fiber reinforced paste 5 is applied and a coating range R2 in which the surface treatment 4 of the steel material 2 is not removed, as necessary. In the meantime, the anticorrosion treatment is performed by providing the anticorrosion material 50 in the gap of the exposed range R1 where the steel material 2 is exposed. As the anticorrosion material 50, for example, waterproof tape, touch-up paint, caulking material, or the like is used, and after the fiber reinforced paste 5 applied to the surface 20 of the steel material 2 is cured, the coating range R2 to the application range R3. It is pasted or applied so as to cover the exposure range R1.

  In the application step, as shown in FIG. 8C, an anticorrosion material 50 such as a waterproof tape is provided on substantially the entire surface of the fiber reinforced paste 5 in the application range R3 where the fiber reinforced paste 5 is applied, as necessary. You may give an anti-corrosion process. At this time, in the coating process, the fiber reinforced paste 5 after coating is completely formed by providing the anticorrosive material 50 on almost the entire surface of the fiber reinforced paste 5 including the gap in the exposed range R1 of the steel material 2 and performing the anticorrosion treatment. It is possible to prevent deterioration of the fiber reinforced paste 5 due to moisture absorption, etc., which may occur when the humidity suddenly increases due to rainfall before being hardened, and at the same time, prevent the steel material 2 from being corroded by electrolytic corrosion or the like. . Furthermore, it becomes easier to secure an appropriate thickness of the fiber reinforced paste 5 by forming the fiber reinforced paste 5 before curing from the top of the anticorrosive material 50 such as a sealing waterproof tape.

  In addition, in the application process, as shown in FIGS. 9 and 10, the steel plate 60, the flat steel, the reinforcing bar 61 or the steel reinforced paste 5 applied to the surface 20 of the steel material 2 is cured before the fiber reinforced paste 5 is cured. A reinforcing material 6 such as a steel bar may be attached to the fiber reinforced paste 5. At this time, in the application step, the reinforcing material 6 such as the steel plate 60 is provided so that the fiber reinforced paste 5 is sandwiched between the surface 20 of the steel material 2 in the application range R3 where the fiber reinforced paste 5 is applied. .

  When the steel plate 60 is provided as the reinforcing member 6, as shown in FIG. 9, the steel plate 60 is bent in advance in accordance with the curvature of the steel structure 8 such as an illumination column. In the application step, the steel plate 60 is attached so as to cover the defective portion 3 of the steel material 2 and the fiber reinforced paste 5 by using the adhesive force of the fiber reinforced paste 5 in the stage before curing. Since the fiber reinforced paste 5 is sandwiched between the steel plate 2 and the surface 20 of the steel material 2, it is not necessary to bend or the like strictly in accordance with the curvature of the steel structure 8 such as an illumination column.

  When the reinforcing bar 61 is provided as the reinforcing member 6, as shown in FIG. 10A, the reinforcing bar 61 is bent in advance in a substantially U shape or the like so as to bypass the rib 81 of the base 8 a such as a lighting column. And In the application step, the reinforcing bars 61 are attached so as to surround the defect portion 3 of the steel material 2 by using the adhesive force of the fiber reinforced paste 5 in the stage before curing. At this time, the reinforcing bar 61 may be provided so as to be exposed from the fiber reinforced paste 5 as shown in FIG. 10B, or embedded in the fiber reinforced paste 5 as shown in FIG. May be.

  In addition, in the coating process, as shown in FIG. 11, a transparent plate such as an acrylic plate, a plastic plate, or a glass plate so that the steel material 2 covers the end portion 3a of the missing portion 3 that is missing in a crack shape as necessary. 31 may be provided. At this time, in the coating process, the transparent plate 31 having translucency is disposed at the position of the end portion 3 a of the defect portion 3, and the end portion 3 a of the defect portion 3 and the transparent plate 31 are not covered with the fiber reinforced paste 5. The fiber reinforced paste 5 is applied so as to surround the transparent plate 31.

  Here, in the coating step, a resin composition containing a room temperature curable thermosetting resin and a filler is mainly used as the fiber reinforced paste 5. And this resin composition contains both a fibrous filler and a non-spherical particle filler as a filler.

  The fiber reinforced paste 5 has a viscosity of 5 to 2000 Pa · s at 25 ° C. at room temperature before curing. The fiber reinforced paste 5 preferably has a viscosity of 50 to 2000 Pa · s at 25 ° C. Since the viscosity of the fiber reinforced paste 5 is in the above range, the resin composition can change the shape of the resin composition applied at the time of coating, and at the same time requires a certain time until the mold collapses. , Molding becomes easy. In addition, the fiber reinforced paste 5 may have a viscosity at 25 ° C. higher than 2000 Pa · s, no fluidity, and a viscosity that cannot be measured without departing from the scope of the present invention. The fiber reinforced paste 5 may have a viscosity of 5 to 2000 Pa · s at 25 ° C. by thickening before curing.

[Normal temperature curable thermosetting resin]
As the room temperature curable thermosetting resin related to the fiber reinforced paste 5, a thermosetting resin capable of room temperature curing is used. Examples of the thermosetting resin include an epoxy resin, a polyurethane resin, an acrylic resin, and a polyester resin. The thermosetting resin is not particularly limited as long as it satisfies the conditions such as the adhesiveness of the coated surface and the strength of the cured product, but from the viewpoint of the adhesiveness with the surface 20 of the steel material 2 and the strength of the cured product, it is an epoxy. Resins are preferably used.

  This epoxy resin is liquid and is preferably a compound having two or more epoxy groups in one molecule. This epoxy resin is, for example, a glycidyl ether type epoxy resin obtained from a polyol, a glycidyl amine type epoxy resin obtained from an amine having a plurality of active hydrogens, a glycidyl ester type epoxy resin obtained from a polycarboxylic acid, or a plurality of in the molecule. A polyepoxide obtained by oxidizing a compound having a double bond is used. Examples of the epoxy resin include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol AD type epoxy resins, bisphenol S type epoxy resins and the like, bisphenol type epoxy resins, epoxy resins having a biphenyl skeleton, and epoxy having a naphthalene skeleton. Resin, epoxy resin having dicyclopentadiene skeleton, phenol novolac epoxy resin, novolac epoxy resin such as cresol novolac epoxy resin, triglycidyl-p-aminophenol, N, N, N ′, N′-tetraglycidyl- Examples thereof include glycidylamine type epoxy resins such as 4,4′-methylenedianiline, resorcin diglycidyl ether, triglycidyl isocyanurate, etc. Nord A type, bisphenol F type, bisphenol AD type, cresol novolak type bifunctional or more liquid epoxy resins such as glycidyl ether type epoxy resins are preferred.

  The fiber reinforced paste 5 is, for example, a two-pack type in which a curing agent is blended with an epoxy resin before construction, and the viscosity immediately after mixing the main agent and the curing agent is 5 to 2000 Pa · s at 25 ° C. At this time, the viscosity of the thermosetting resin as the main agent is desirably in the range of 0.5 to 30 Pa · s at 25 ° C., and more preferably 0.7 to 20 Pa · s. When the viscosity is less than 0.5 Pa · s, there is a problem that the fiber-reinforced paste 5 is liable to sag during coating and the necessary strength cannot be obtained. In addition, when the viscosity is more than 30 Pa · s, there are problems that the filler is difficult to knead, and the viscosity of the fiber reinforced paste 5 is too high to make coating difficult. The measurement of the viscosity of the fiber reinforced paste 5 can be performed according to the viscosity test method of JIS K 7233 epoxy resin and a curing agent.

  When the fiber reinforced paste 5 is used by mixing the main agent and the curing agent, the curing agent is not particularly limited as long as it can be cured at room temperature, and is not particularly limited, such as an acid anhydride type or an amine type. Considering the pot life and usage environment, amine-based curing agents are preferred. Examples of the amine-based curing agent include aliphatic polyamines such as diethylenetriamine, alicyclic polyamines such as isophoronediamine, aromatic amines such as diaminodiphenolsulfone, and modified products thereof. As amine-based curing agents, liquid aliphatic polyamines having a viscosity in the range of 0.01 to 2 Pa · s and their modified products can be cured at room temperature for a short time and can be easily mixed at the time of construction. Can be preferably used. Moreover, there is no restriction | limiting in particular about the compounding ratio of a hardening | curing agent, However, What has an amine number that the ratio of a hardening | curing agent will be 20-100 parts with respect to 100 parts of equivalent of the epoxy resin used as a main ingredient is preferable.

  In order to obtain a sufficient tensile elastic modulus to suppress crack growth in the coating type, the mixing ratio of fibrous filler and non-spherical particle filler that is optimal for room temperature curing type thermosetting resin is examined. did. Optimizing the blending ratio of these fillers increases the viscosity of the resulting resin composition, so that not only the reinforcing effect of the resin composition after blending is obtained, but also in terms of construction such as dripping prevention during coating. The merit is also obtained.

[Fibrous filler]
As the fibrous filler according to the fiber reinforced paste 5, inorganic fibers such as carbon fibers, glass fibers, rock wool fibers, and organic fibers composed of polymers can be used, and a mixture thereof can also be used. Carbon fiber and glass fiber, or a mixture thereof are more preferable in terms of handling during production. More preferably, the fibrous filler according to the fiber reinforced paste 5 is a chopped carbon fiber or glass fiber having a length of 3 mm or more and a fiber diameter of less than 30 μm per fiber in terms of the tensile elasticity. Strand fibers can be used. In addition, although the fibrous filler which concerns on the fiber reinforced paste 5 is not limited, in order to improve the affinity with a matrix material, this fibrous filler is, for example, sizing treatment such as epoxy resin sizing or silane coupling. Those subjected to surface treatment with an agent or the like are preferable.

[Non-spherical particle filler]
As the non-spherical particle filler according to the fiber reinforced paste 5, pitch coke pulverized product, talc, mica, clay, calcium carbonate, carbon black, graphite pulverized product, wollastonite, crushed silica powder, resin-based fine particles and the like can be used. Mixtures of these can also be used. As the non-spherical particle filler related to the fiber-reinforced paste 5, the non-spherical filler such as pitch coke pulverized product, talc, mica, etc. has a scale-like particle shape. It is preferable because it is easily expressed. The non-spherical particle filler according to the fiber reinforced paste 5 is more preferably a pitch coke crushed having a scaly shape, a high elastic modulus of itself, and excellent compatibility with a resin composition composed of a carbon-based element. It is a product. In particular, pitch coke pulverized products with needle-like crystallinity made from coal-based tar have high strength and elastic modulus of the pulverized particles, and most of the composition is carbon. Differently, a non-spherical particle filler that is most preferable as the non-spherical particle filler according to the fiber-reinforced paste 5 can be obtained without using a compatibilizing agent or the like, and can exhibit strength and elastic modulus, and can be easily scaled when pulverized. It is.

  The non-spherical particle filler used by being incorporated in the fiber reinforced paste 5 has an average particle diameter of 1 to 80 μm, preferably 1 to 50 μm, more preferably 1 to 30 μm, and still more preferably an average particle diameter of 5 to 20 μm. It is. A non-spherical filler having an average particle size of less than 1 μm is not preferable because it significantly increases the viscosity when mixed with the thermosetting resin mixture, and thus makes coating difficult. Further, a non-spherical filler having an average particle size of more than 80 μm is not preferable because the strength of the thermosetting resin mixture cannot be obtained. The average particle size of the non-spherical particle filler in the fiber reinforced paste 5 is the median diameter (D50) of the non-spherical particle filler measured by a laser diffraction / scattering particle size distribution measuring device.

[Filler blending amount]
The fiber reinforced paste 5 contains a total of 20 to 150 parts by weight of a fibrous filler and a non-spherical particle filler, preferably 40 to 120 parts by weight, with respect to 100 parts by weight of a room temperature curable thermosetting resin. It is blended with. When the blending amount of the fibrous filler and the non-spherical particle filler is less than 20 parts by weight with respect to 100 parts by weight of the thermosetting resin that cures at room temperature, the tensile elastic modulus for obtaining the reinforcing effect cannot be obtained. In addition, when the blending amount exceeds 150 parts by weight, voids generated in the resin composition increase, resulting in a decrease in strength of the fiber reinforced paste 5 itself.

  Moreover, the fiber reinforced paste 5 is 1-10 in the following formula (1), more preferably 2-8, in the following formula (1). To be. When the blending ratio is less than 1, sufficient tensile elastic modulus for obtaining the reinforcing effect cannot be obtained, and when the blending ratio exceeds 10, not only sufficient tensile elastic modulus for obtaining the reinforcing effect, Tensile strength can no longer be obtained.

  Blending amount of non-spherical particle filler / blending amount of fibrous filler = 1 to 10 (1)

  In the fiber reinforced paste 5, the blending ratio of the thermosetting resin, the fibrous filler, and the non-spherical particle filler is 3 to 30 parts by weight of the fibrous filler with respect to 100 parts by weight of the thermosetting resin. Is preferably 10 to 120 parts by weight, more preferably 5 to 20 parts by weight of the fibrous filler and 20 to 100 parts by weight of the non-spherical particle filler. If the blending amount of the fibrous filler and the non-spherical particle filler is within this range, there will be no problem in construction and mechanical properties such as the obtained elastic modulus and strength. In particular, the above formula (1) It is possible to design to the compounding ratio and to enhance the crack growth suppressing effect.

  As one of the embodiments of the fiber reinforced paste 5, by mixing a chopped fibrous filler and a non-spherical particle filler with a thermosetting resin that can be cured at room temperature, an adhesive or the like can be used on-site. A fiber reinforced paste 5 that can easily be applied to the vertical portion and can exhibit a tensile elastic modulus that suppresses the growth of cracks in the steel material 2 has been realized.

  Moreover, in the range which does not impair the physical property of the fiber reinforced paste 5, it is for thermosetting resin other than the thermosetting resin used for matrix resin, inorganic filler, combined use of an organic filler, and also for dispersibility and adhesive improvement. Additives such as silane coupling agents, UV inhibitors, thermal degradation inhibitors, antioxidants, flow control agents, and the like may be used in combination.

  The fiber reinforced paste 5 may be a two-component resin composition in which a thermosetting resin (main agent) and a curing agent are separately provided, and an operator mixes both of them immediately before work. By using a two-component resin composition, it is possible to use a highly reactive curing agent, enabling on-site construction in a short period of time, and storing the main agent and curing agent separately. It can be stored for a long time without any particular restrictions on conditions, and can be quickly constructed as necessary.

  Although the fiber reinforced paste 5 is not limited, in the production of the fiber reinforced paste 5, it is preferable to use a mixer such as a general helical mixer, a Henschel mixer, a Dalton mixer, or a centrifugal mixer. It is more preferable to reduce the pressure in these mixings because the bubbles included in the mixture can be removed.

  Moreover, although the fiber reinforced paste 5 is not limited, it is preferable that the fiber reinforced paste 5 is mixed with the resin and the curing agent immediately before the coating work because of the ease of the coating workability in the outdoor construction site. . For example, the fiber reinforced paste 5 is prepared by preparing a mixture in which fibrous and particulate fillers are mixed in advance with a main resin varnish or a curing agent, and a necessary amount of the main resin varnish or a curing agent is added to the mixture immediately before the coating operation. It is preferable to use a mixture. In this case, the mixture prepared in advance may be a mixture of the main agent, fibrous filler and particulate filler, one of the fillers is mixed with the main agent, and the other filler is mixed with the curing agent to be used. It may be a way to prepare things. Considering the convenience during construction, a method of preparing a mixed varnish in which a main resin varnish, a fibrous filler and a particulate filler are mixed, and mixing a curing agent immediately before the coating operation is preferable. On the other hand, a method of preparing a mixed curing agent in which a curing agent, a fibrous filler, and a non-spherical particle filler are mixed and mixing the main resin varnish immediately before the coating operation is also preferably used, but the main mixture has a high viscosity. The method of adding the one having a lower viscosity is more preferable because of good handling properties. The mixing method at the construction site is not particularly limited, but a method of mixing with a drum can-mounted mixer or a handy-type mixer is preferable from the viewpoint that it is simple and has a low work load during construction. An example of a drum can type mixer is Seken made mazel, and an example of a handy type mixer is a handy type Otsuka brush mother.

  Although it does not limit the fiber reinforced paste 5, about the mixture which mixed the main ingredient resin varnish and the hardening | curing agent, a viscosity is 5-2000 Pa.s at 25 degreeC, More preferably, a viscosity is 50-at 25 degreeC. A pressure of 2000 Pa · s is preferable in order to simplify the coating on the wall or ceiling. For this reason, it is preferable that the viscosity immediately after mixing is 10 to 2000 Pa · s at 25 ° C., more preferably 30 to 1500 Pa · s, and more preferably 50 to 1000 Pa in terms of prevention of sagging during coating and handling. -More preferably, it is s. In addition, the mixture may have a viscosity higher than 2000 Pa · s, no fluidity, and a viscosity that cannot be measured without departing from the spirit of the present invention.

  The fiber reinforced paste 5 may have thixotropic properties (thixotropic properties) due to the property of being a resin composition containing a thermosetting resin and a filler. Although the fiber reinforced paste 5 is not limited, the thixotropic index of the thixotropic property (thixotropic property) of the medium viscosity type in the standard JIS A 6024: 2008 of the epoxy resin for building repair is 5 ± 1, The fiber reinforced paste 5 may exhibit a thixotropic index of 4 or more, preferably 5 or more, as measured in the same standard. When the thixotropic index is within the above range, the resin composition of the fiber reinforced paste 5 is not easily lost during coating, and coating and molding are easy. The curing time of the fiber reinforced paste 5 is preferably about 10 minutes to 5 hours in terms of construction work, and more preferably about 30 minutes to 3 hours. In addition, as an easy confirmation method of a good cured state, after coating the mixture immediately after mixing the main resin varnish and the curing agent to a thickness of 20 mm with respect to the horizontal plane, the change in thickness after 2 hours It is preferably cured within 2 mm.

  Although this invention is not limited, if the humidity conditions during construction are extremely high, the composition before curing that has been molded or applied after mixing should be protected against moisture absorption by protecting its surface with sheets. Is desirable. These sheets may be the same as those used as the anticorrosion material 50 applied or pasted in the gap of the exposed range R1 where the steel material 2 is exposed for the purpose of anticorrosion. For this anticorrosion material 50, for example, a silicone adhesive sheet for construction and civil engineering manufactured by Shin-Etsu Chemical Co., Ltd., Shin-Etsu Patch Seal HNS-200, or the like is preferably used.

  Although the fiber reinforced paste 5 is not limited, the fiber reinforced paste 5 preferably has, for example, a tensile shear strength of 1 MPa or more indicating adhesion to the general structural material rolled steel SS400. Even if the tensile shear strength is less than this, there is no particular problem. However, it is sometimes excellent in terms of long-term durability or the like that the peeling after coating is less likely to occur.

[Coating method]
The application method of the fiber reinforced paste 5 is not particularly limited as long as it can apply a material having a viscosity of 5 to 2000 Pa · s at 25 ° C., and a generally used method can be used. The fiber reinforced paste 5 is a steel material 2 used for the steel structure 8 and is applied and cured so as to cover the defect portion 3, thereby exhibiting a crack growth suppressing effect. The thickness to be applied is not particularly limited as long as coating is possible and sufficient strength is maintained after curing. The fiber reinforced paste 5 has a high crack growth suppressing effect when applied to the defect portion 3 of the steel material 2 at a thickness of about 1 mm to about 30 mm, preferably about 10 mm to 20 mm. The curing method can be cured at room temperature, but a generally used method such as heating can be used as necessary. In applying the fiber reinforced paste 5, a primer may be used in order to improve adhesion. Although the kind of this primer is suitably selected according to the material of the steel material 2 to reinforce and the resin kind of the fiber reinforced paste 5, for example, an epoxy resin type primer or a silane coupling agent type primer is preferably mentioned.

  As shown in FIG. 12, the reinforcing structure 1 and the reinforcing method to which the present invention is applied include a fiber reinforced paste 5 so as to expose the steel material 2 around the defect portion 3 of the steel material 2 and cover the defect portion 3 of the steel material 2. Is applied. In the reinforcing structure 1 and the reinforcing method to which the present invention is applied, the fiber-reinforced paste 5 applied to the surface 20 of the steel material 2 is bonded to the surface 20 of the steel material 2 at the stage before curing, and the stage after curing. Thus, the steel material 2 is fixed across the missing portion 3.

  In the reinforcing structure 1 and the reinforcing method to which the present invention is applied, the fiber reinforced paste 5 is bonded to the surface 20 of the steel material 2, and the one end side 51 a and the other end side 51 b across the defect portion 3 are bonded surfaces of the fiber reinforced paste 5. 51. The reinforcing structure 1 and the reinforcing method to which the present invention is applied are such that the fiber reinforced paste 5 is fixed across the defect portion 3 and cured from one end side 51a to the other end side 51b of the bonding surface 51 of the fiber reinforced paste 5. Stress is transmitted through the subsequent fiber reinforced paste 5.

  At this time, in the reinforcing structure 1 and the reinforcing method to which the present invention is applied, stress is transmitted through the fiber reinforced paste 5 applied so as to cover the defect portion 3 of the steel material 2, so that the steel material 2 of the steel structure 8 is partially Even when a general defect occurs, the steel structure 8 can be sufficiently reinforced. In addition, the reinforcing structure 1 and the reinforcing method to which the present invention is applied mainly consist of the application work of the fiber reinforced paste 5 and can easily reinforce and repair the defective portion 3 of the steel material 2, thereby reducing the work burden during construction. In addition, it is possible to suppress the progress of cracks and the like generated in the steel material 2 of the steel structure 8 and to recover the strength decrease due to the cross-sectional reduction caused by cracks and corrosion.

  In particular, the reinforcing structure 1 and the reinforcing method to which the present invention is applied, as shown in FIG. 13 (a), the coating range R2 of the steel material 2 is applied to the exposed range R1 of the steel material 2 without applying the fiber reinforced paste 5. Only the fiber reinforced paste 5 is preferably applied. At this time, in the reinforcing structure 1 and the reinforcing method to which the present invention is applied, the adhesive surface 51 of the fiber reinforced paste 5 becomes difficult to peel off, and the reinforcing effect by the fiber reinforced paste 5 can be improved. On the other hand, as shown in FIG. 13 (b), when the fiber reinforced paste 5 is applied also to the coating range R2 of the steel material 2, the fiber reinforced paste 5 overlaps with the surface treatment 4 and is plated or painted. Since the bonding surface 51 is easily peeled off, the reinforcing effect of the fiber reinforced paste 5 is reduced.

  Further, in the reinforcing structure 1 and the reinforcing method to which the present invention is applied, the fiber reinforced paste 5 is applied only to the exposed range R1 of the steel material 2 as shown in FIG. A gap in which the steel material 2 is exposed may be formed between the steel material 2 and the coating range R2. At this time, the reinforcing structure 1 and the reinforcing method to which the present invention is applied are the steel material from the gap between the coating range R3 and the coating range R2 by providing the anticorrosion material 50 in the gap where the steel material 2 is exposed and performing the anticorrosion treatment. It is possible to prevent 2 from being corroded by electric corrosion or the like.

  Further, the reinforcing structure 1 and the reinforcing method to which the present invention is applied are provided so that the reinforcing material 6 such as the steel plate 60 shown in FIGS. 9 and 10 sandwiches the fiber reinforced paste 5 between the surface 20 of the steel material 2. It is desirable. At this time, as shown in FIG. 14 (a), the reinforcing structure 1 and the reinforcing method to which the present invention is applied have a steel structure by transmitting stress to the reinforcing material 6 bonded to the fiber reinforced paste 5 as well. The reinforcement effect for 8 can be improved.

  Further, in the reinforcing structure 1 and the reinforcing method to which the present invention is applied, since stress is transmitted also to the reinforcing material 6, as shown in FIG. 14 (b), the thickness to which the fiber reinforced paste 5 is applied is reduced. Also, the fiber reinforced paste 5 and the reinforcing material 6 are combined to obtain a sufficient reinforcing effect. At this time, in the reinforcing structure 1 and the reinforcing method to which the present invention is applied, the strength per unit thickness of the fiber reinforced paste 5 is improved by reducing the thickness of the fiber reinforced paste 5. It is possible to efficiently improve the reinforcing effect while suppressing the amount used.

  Here, when reinforcing the columnar steel structure 8 such as an illumination column or a sign column, as shown in FIG. 15, the stress generated in the height direction of the steel structure 8 is the circumferential direction of the steel structure 8. Therefore, the height direction of the steel structure 8 is the main stress acting direction α. And the reinforcement structure 1 and the reinforcement construction method to which this invention is applied are the coating | coated in which the surface treatment 4 of the steel material 2 is not removed especially in the part substantially orthogonal to the action direction (alpha) of the main stress which acts on the steel structure 8. The fiber reinforced paste 5 is applied only to the exposed range R1 without applying the fiber reinforced paste 5 to the range R2. At this time, when the columnar steel structure 8 is reinforced, the fiber reinforced paste 5 is applied so as not to overlap the surface treatment 4 on both the upper and lower sides of the exposed range R1 in the height direction which is the main stress application direction α. However, the fiber reinforced paste 5 may be applied so as to overlap the surface treatment 4 on both the left and right sides of the exposure range R1 in the circumferential direction that does not become the main stress application direction α. When the steel structure 8 to be reinforced is not columnar, the stress generated in the left-right direction of the steel structure 8 is larger than the stress generated in the up-down direction, and the left-right direction of the steel structure 8 is the main stress. There may be a direction of action α.

  Note that, in the reinforcing structure 1 and the reinforcing method to which the present invention is applied, as shown in FIG. 5, the fiber reinforced paste 5 is applied only around the defect portion 3 of the steel material 2 in a part of the circumferential direction of the steel structure 8. In addition, as shown in FIG. 16, the fiber reinforced paste 5 may be applied over substantially the entire circumference of the steel structure 8. At this time, the reinforcing structure 1 and the reinforcing method to which the present invention is applied improve the strength per unit thickness by reducing the thickness of the fiber reinforced paste 5 while increasing the total amount of the fiber reinforced paste 5 to be applied. As a result, the reinforcing effect can be improved efficiently. Moreover, since the reinforcing structure 1 and the reinforcing method to which the present invention is applied wraps the steel structure 8 with the fiber reinforced paste 5 applied over substantially the entire circumference of the steel structure 8, only the adhesion force of the fiber reinforced paste 5 can be obtained. In addition, the stress is transmitted to the fiber reinforced paste 5 by the supporting pressure, so that it is possible to increase the load carrying capacity and prevent the adhesion from being cut off, and it is possible to greatly reduce the risk due to the sticking out.

  In the reinforcing structure 1 and the reinforcing method to which the present invention is applied, the stop hole 30 may be formed in the end portion 3a of the defective portion 3 formed sharply in the steel material 2, as shown in FIG. At this time, the reinforcing structure 1 and the reinforcing method to which the present invention is applied are such that even if the steel material 2 is cracked and the end 3a of the defect 3 is sharp, the end of the defect 3 of the steel 2 Since the stop hole 30 is formed in 3a and the stress concentration at the end portion 3a of the defect portion 3 is relaxed, it is possible to suppress the progress of the crack.

  As shown in FIG. 11, the reinforcing structure 1 and the reinforcing method to which the present invention is applied are provided with a transparent plate 31 so as to cover the end portion 3a of the defect portion 3 in which the steel material 2 is broken like a crack. The fiber reinforced paste 5 may be applied so as to surround without covering 31. At this time, as shown in FIG. 17A, the reinforcing structure 1 and the reinforcing method to which the present invention is applied ensure the visibility by the transparent plate 31 at the end portion 3a of the defective portion 3, thereby preventing the defective portion. It is possible to follow the crack condition of the end portion 3a of the third.

  Moreover, since the reinforcing structure 1 and the reinforcing method to which the present invention is applied apply the fiber reinforced paste 5 so as to surround the transparent plate 31, it is a simple operation that only applies according to the plate thickness of the transparent plate 31, and the fiber The thickness to which the reinforcing paste 5 is applied can be made accurate. Note that the reinforcing structure 1 and the reinforcing method to which the present invention is applied, as shown in FIG. 17B, when the transparent plate 31 and the steel plate 60 are used together, By notching the portion, it is possible to observe the progress of the crack without being blocked by the steel plate 60 that is the reinforcing member 6.

  Furthermore, in the reinforcing structure 1 and the reinforcing method to which the present invention is applied, it is desirable to use a predetermined resin composition containing a room temperature curable thermosetting resin and a filler as the fiber reinforced paste 5. At this time, the reinforcing structure 1 and the reinforcing method to which the present invention is applied are simple and can suppress the crack propagation and the like of the defective portion 3 of the steel material 2 by using a method with less work load at the time of construction. . In addition, the reinforcing structure 1 and the reinforcing method to which the present invention is applied are realized by changing the thickness and shape of applying the fiber reinforced paste 5 in various ways to realize a flexible design of the cross-sectional area and the bonding area of the reinforcing portion. It becomes possible to reinforce the defect portion 3 of various aspects in various types of steel materials 2.

  Next, in order to verify the reinforcing effect by the reinforcing structure 1 and the reinforcing method to which the present invention is applied, a tensile test and a fatigue test were performed. In the design of the test body, as the fiber reinforced paste 5, epoxy resin YD-128 (bisphenol A type liquid epoxy resin, viscosity 12 Pa · s) manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. and curing agent FXD821- manufactured by T & K TOKA Co., Ltd. Pitch coke powder manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., which is a non-spherical particle filler, with respect to 100 parts of a resin composition in which F (modified alicyclic polyamine curing agent, viscosity 0.065 Pa · s) is mixed 100 to 45 40 parts of an average particle diameter of 15 μm) and 0.5 parts of a silane coupling material (Glycidyl silane coupling agent A-187 manufactured by Momentive Performance Materials) were added, and the rotation and revolution made by Inoue Manufacturing Co., Ltd. A mixture with a viscosity of 150 Pa · s by mixing at room temperature using a type planetary mixer After that, 10 parts of chopped carbon fiber having a fiber length of 6 mm (80NT manufactured by Nippon Graphite Fiber Co., Ltd.) as a fibrous filler was added to this mixture, and the resulting mixture was poured into a tray. JIS_K7162-test piece 1B type obtained by cutting from a flat plate after standing still, the tensile strength of the fiber reinforced paste itself is 25 MPa, and the flat bar of SS400 with the steel material surface blasted in the same manner Further, a shear test piece according to JIS_K6850 was prepared, and the fiber reinforced paste 5 having an adhesive strength after curing of the fiber reinforced paste itself of 8 MPa was used. And in the tensile test, the test body shown in FIG. 18 was used. Moreover, in the curing of the epoxy resin using an amine curing agent, this mixing operation was performed in a room with an environmental condition of 25 ° C. and 60 RH% in order to prevent deterioration due to moisture absorption before curing.

  The design of the specimen for the tensile test was based on the premise that the fiber reinforced paste 5 supplements the cross-sectional area of the steel material 2 lost due to the defect portion 3 and the stop hole 30. In addition, for the actual steel structure 8, the fiber reinforced paste 5 is applied from one side. However, if the specimen is an asymmetric material, additional bending due to axial deviation occurs and it is difficult to understand the results. For this reason, it was set as the board thickness of the steel pipe assumed with an illumination pillar, and the fiber reinforcement paste 5 was coated on both surfaces.

  First, the width of the defect portion 3 and the stop hole 30 was set to 50 mm. This was set based on the prediction that it would be impossible to find unless the size of the defect portion 3 was 30 mm or more. The setting was such that 10 mm diameter stop holes 30 were provided at both ends of the 30 mm. Although the diameter of 10 mm is small as the stop hole 30, for example, the outer diameter of the steel pipe is less than 200 mm.

Considering that the cross-sectional area of the steel material 2 lost due to the defect 3 and the stop hole 30 is supplemented with the fiber reinforced paste 5, it is necessary to satisfy “lost steel strength F _S ≦ strength F _C of the fiber reinforced paste 5”. Therefore, the relationship of the following formula (2) is established, where the coating thickness of the fiber reinforced paste 5 is t. Further, considering that the shared load of the fiber reinforced paste 5 is transmitted by the adhesive force, it is necessary to satisfy “lost steel strength F _S ≦ adhesive strength F _B of the fiber reinforced paste 5”. The required application length L (application area) of 5 is expressed by the following equation (3).

F _S = A × σ _s = 50 × 4.5 × 235 ≦ F _C = 100 × t × 25 (2)
Here, the width of the defect portion 3 and the stop hole 30 is 50 mm, the thickness of the steel material 2 is 4.5 mm, the strength of the steel material 2 is 235 MPa, the application width of the fiber reinforced paste 5 is 100 mm, and the tensile strength of the fiber reinforced paste 5 Is 25 MPa.

F _S = 50 × 4.5 × 235 ≦ F _B = 100 × L × 8 (3)
Here, the width of the defect portion 3 and the stop hole 30 is 50 mm, the thickness of the steel material 2 is 4.5 mm, the strength of the steel material 2 is 235 MPa, the application width of the fiber reinforced paste 5 is 100 mm, and the adhesive strength of the fiber reinforced paste 5 Is 8 MPa.

  Table 1 shows a list of test specimens. The parameters are the application length, the application thickness, and the direction of application of the fiber reinforced paste 5. No. No. 4 has a coating thickness of 20 mm and a coating length of 100 mm on one side (overall length 200 mm). At the time of coating, the test specimen is placed on the floor and the work is performed with the operator facing down. No. In Nos. 2 and 3, the coating length is 150 mm on one side (overall length 300 mm). No. In No. 3, a test body is set up assuming that the actual lighting column is applied only to the coating, and the construction is carried out so that the worker faces sideways. If these coating materials perform sufficiently, the coating material should surely have sufficient adhesion and avoid peeling. Since the coating thickness is difficult to control, the total thickness of the finished mold was measured at 5 points using a caliper immediately above the defect 3.

  According to the result of the tensile test, as shown in FIG. It was confirmed that any of the specimens 2 to 4 exhibited strength exceeding the design load. Also, as shown in FIG. 20, when the horizontal axis is the average thickness of the test specimen and the vertical axis is the load at the time when the fiber reinforced paste 5 is broken or peeled off, the breakage occurs when the coating thickness t of the fiber reinforced paste 5 is large. It is confirmed that the load at the time is also increased, and the possibility of peeling is reduced. In addition, the average thickness of this test body is the average value which measured the application | coating thickness t of the fiber reinforced paste 5 in both surfaces of the steel material 2 at 5 points | pieces, and the plate | board thickness (4.5 mm x 2 = 9 mm) of a test body The total value of

  Next, in the fatigue test, the specimen shown in FIG. 21 was used, and before applying the fiber reinforced paste 5, the fatigue test was first performed in the state of only the steel material 2 to introduce a fatigue crack. In that case, it was impossible to generate a fatigue crack in the state where the stop hole 30 was provided because of the setting of the size of the specimen. For this reason, the fatigue test was carried out with the slit of 40 mm length provided by laser processing without providing the stop hole 30, a fatigue crack was introduced, and then the fatigue test was performed again by applying the fiber reinforced paste 5. . The application thickness of the fiber reinforced paste 5 was 20 mm, and the application length was 100 mm on one side (total length 200 mm).

  According to the results of the fatigue test, as shown in Table 2, no. It was confirmed that any of the specimens 1 to 4 exhibited fatigue strength exceeding 100,000 times. For this reason, it was confirmed that the coated portion of the fiber reinforced paste 5 does not peel even after repeated fatigue loading and exhibits the effect of suppressing the growth of fatigue cracks. And it was estimated that almost no peeling of the fiber reinforced paste 5 occurred until the steel material 2 was broken. It should be noted that there was no significant change in performance depending on the coating posture, whether the construction was performed with the worker facing down or the construction was performed with the worker facing sideways.

  In the above, the situation where the present invention is applied mainly to the base 8a of the lighting column or the marker column has been described. Other than that, for example, as shown in FIG. 22, the present invention can be applied to the ground corrosion of the steel pipe 7 in order to reinforce the steel structure 8 such as the steel pipe 7 to be a guardrail pole. Here, the steel pipe 7 serving as a guardrail pole or the like has a bottom surface 7a of a steel pipe 7 embedded in a base 70 such as concrete, and serves as a boundary between a portion embedded in the base 70 and a portion exposed to the ground surface. Corrosion occurs at this time, and the steel material 2 is partially lost to form a defect 3.

  When reinforcing the steel structure 8 against such ground corrosion, as shown in FIG. 23, an anchor 71 is installed in the vicinity of the steel pipe 7 and the fiber reinforced paste 5 is applied so as to wrap the anchor 71. It is desirable. At this time, in the reinforcing structure 1 and the reinforcing method to which the present invention is applied, since the lower end portion 7a of most of the steel pipes 7 is embedded in the concrete base 70, the base 70 in the vicinity of the steel pipe 7 is drilled with a drill or the like. The anchor 71 is installed as a chemical anchor. In addition, it is desirable for the anchor 71 to have a steel material strength equivalent to the proof stress lost due to partial loss of the steel material 2. Furthermore, the fiber reinforced paste 5 is applied over substantially the entire circumference of the steel pipe 7 so that, for example, the height H of the fiber reinforced paste 5 from the base 70 is about twice or more the outer diameter D of the steel pipe 7. Is desirable. At this time, when the height H of the fiber reinforced paste 5 is twice or more the outer diameter D of the steel pipe 7, the stress transmission from the steel pipe 7 to the fiber reinforced paste 5 is due to the adhesive force of the fiber reinforced paste 5. It is secondary and mainly depends on the support pressure of the fiber reinforced paste 5 against the steel structure 8. In addition, by removing the surface treatment 4 existing at the end of the fiber reinforced paste 5, the adhesion at the interface 7b between the fiber reinforced paste 5 and the steel pipe 7 is improved, and the water channel at the interface 7b is blocked. Therefore, the long-term deterioration factor of the steel pipe 7 can be reduced.

  As shown in FIG. 24, the reinforcing structure 1 and the reinforcing method to which the present invention is applied are larger than the outer diameter D of the partially missing steel pipe 7 so as to surround the periphery of the base 8a of the partially missing steel pipe 7. A coating steel pipe 72 having an inner diameter D ′ may be provided. At this time, the coating steel pipe 72 is filled with the fiber reinforced paste 5 in the gap G between the coating steel pipe 72 and the steel pipe 7 at a height H that is at least twice as large as the outer diameter D of the partially lost steel pipe 7. Thus, a higher reinforcing effect can be exhibited. At this time, the anchor 71 may be inserted into the gap G between the covering steel pipe 72 and the steel pipe 7 to transmit the stress via the fiber reinforced paste 5 and the anchor 71, and the covering steel pipe 72 and the steel pipe 7 are welded. They may be directly integrated by joining or bolt joining. When stress is transmitted through the anchor 71, the upper end of the anchor 71 is bent to form the hook portion 71a, and the hook portion 71a is hooked on the upper end edge of the covering steel pipe 72, thereby ensuring stress transmission. .

  As mentioned above, although the example of embodiment of this invention was demonstrated in detail, all the embodiment mentioned above showed only the example of actualization in implementing this invention, and these are the technical aspects of this invention. The range should not be interpreted in a limited way.

DESCRIPTION OF SYMBOLS 1: Reinforcement structure 2: Steel material 20: Surface 3: Defect part 3a: End part 30: Stop hole 31: Transparent board 4: Surface treatment 40: Disc grinder 5: Fiber reinforcement paste 50: Anticorrosive 51: Adhesive surface 51a: One end Side 51b: Other end side 6: Reinforcement material 60: Steel plate 61: Reinforcing bar 7: Steel pipe 7a: Lower end 7b: Interface 70: Base 71: Anchor 71a: Hook 72: Steel pipe 8 for covering 8: Steel structure 8a: Base 8b : Opening 81: Rib R1: Exposure range R2: Covering range R3: Application range

Claims (10)

A reinforcing method for reinforcing a partially missing steel structure,
A removal step of removing the surface treatment from the steel material used for the steel structure, and an application step of applying a fiber reinforced paste to the surface of the steel material,
In the removing step, the steel material is exposed by removing the plating or coating provided as a surface treatment of the steel material around the defect portion where the steel material is partially lost,
In the application step, the fiber reinforced paste is applied so as to cover the defect portion in an exposed range in which the steel material is exposed by removing a surface treatment. In the coating step, in the portion substantially orthogonal to the acting direction of the main stress acting on the steel structure, the exposed area without applying the fiber reinforced paste to the coating area where the surface treatment of the steel material is not removed. The reinforcing method according to claim 1, wherein the fiber-reinforced paste is applied only in a range. The reinforcing method according to claim 2, wherein, in the application step, an anticorrosion treatment is performed by providing an anticorrosive material in the exposed range between an application range where the fiber reinforced paste is applied and the coating range. The said application | coating process performs an anti-corrosion process by providing an anti-corrosion material in the substantially whole surface of the said fiber reinforced paste in the application | coating range which apply | coated the said fiber reinforced paste. Reinforcement construction method. The said removal process WHEREIN: The stop hole which suppresses the progress of the crack of the said defect | deletion part is formed in the said steel material in the edge part of the said defect | deletion part which the said steel material defect | deleted in the shape of a crack. 4. The reinforcing method according to any one of 4 above. In the said application | coating process, a reinforcing material is provided so that the said fiber reinforced paste may be inserted | pinched between the surfaces of the said steel materials in the application range which apply | coated the said fiber reinforced paste. Reinforcing method described in item 1. In the application step, a transparent plate is provided so as to cover an end portion of the defect portion in which the steel material is cracked, and the fiber reinforced paste is applied so as to surround the transparent plate. Item 7. The reinforcing method according to any one of items 1 to 6. In the said application | coating process, the said fiber reinforced paste is apply | coated over substantially the perimeter of the steel structure partially lost. The reinforcement construction method in any one of Claims 1-7 characterized by the above-mentioned. In the coating step, a resin composition containing a room temperature curable thermosetting resin and a filler is used as the fiber reinforced paste,
The resin composition contains both a fibrous filler and a non-spherical particle filler as the filler, has a viscosity of 5 to 2000 Pa · s at 25 ° C., and 100 parts by weight of a room temperature curable thermosetting resin. The fibrous filler and non-spherical particle filler are expressed by the following formula (1)
Blending amount of non-spherical particle filler / blending amount of fibrous filler = 1 to 10 (1)
The reinforcing method according to any one of claims 1 to 8, wherein the blending ratio is 20 to 150 parts by weight in total and the average particle diameter of the non-spherical particle filler is 1 to 80 µm. A reinforcing structure for reinforcing a partially missing steel structure,
Provided with fiber reinforced paste applied to the surface of steel used in steel structures,
The fiber reinforced paste covers the defect portion in an exposed range in which the steel material is exposed by removing plating or coating provided as a surface treatment of the steel material around the defect portion where the steel material is partially missing. The reinforcing structure is characterized by being applied as follows.

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