Rust-proofing method for rebar

Abstract

To solve the problem that in a precast concrete construction method, precast concrete products with embedded rebar need to be stored until they are transported to the construction site, and this storage period is often long, so it is important to find a way to prevent the rebar exposed in the concrete from rusting during storage.SOLUTION: The rust-proofing method is a rust-proofing method for exposed rebar in precast concrete, and includes a covering step of covering the rebar with a resin bag 1 containing a rust inhibitor, and a fixing step of fixing the rust-preventive resin bag 1. According to this rust-proofing method, the rust-proofing effect of the rebar can be easily improved by directly covering the rebar with the resin bag 1 containing the rust inhibitor. By sufficiently preventing rust from building up in a rebar portion 22, the durability and lifespan of the precast concrete are extended, and deterioration of the concrete and repair costs are reduced.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a method for preventing rust on reinforcing bars of precast concrete during storage. [Background technology]

[0002] Traditionally, the precast concrete method has been used in the construction of concrete structures. Concrete structures are usually built by setting up formwork at the construction site and pouring concrete into it, but the precast concrete method is a method in which precast concrete products are manufactured by pouring concrete into formwork with rebars prepared in advance at a facility such as a factory separate from the construction site, forming and hardening the concrete, and then transporting it to the construction site for assembly.

[0003] Precast products are stored for a specified period of time before being transported to the construction site where they are assembled. During this storage period, for example one to one and a half years, the concrete materials become accustomed and their strength increases.

[0004] By the way, the reinforcing bars in reinforced concrete structures play an important role in ensuring the strength and durability of the concrete structure. The reinforcing bars can rust due to the effects of humidity and salt, which can shorten the lifespan of the entire structure.

[0005] Therefore, in order to prevent rust, anti-rust treatment is applied to the reinforcing bars to ensure the strength and durability of the concrete structure. For example, Patent Document 1 describes a highly durable deck made of precast concrete, in which anti-rust paint is applied to protruding screw-processed parts. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Publication 2018-76728 Summary of the Invention [Problem to be solved by the invention]

[0007] Although Patent Document 1 describes applying anti-rust treatment to precast concrete products when they are assembled, precast concrete construction methods require that precast concrete products with embedded rebar be stored until they are transported to the construction site. This storage period is often long, so it is important to have a method of preventing the rebar exposed in the concrete from rusting during storage.

[0008] (1) The method for preventing rust of reinforcing bars according to the present invention is a method for preventing rust of exposed reinforcing bars in precast concrete, and is characterized in that it includes a covering step of covering the reinforcing bars with a resin bag containing a rust inhibitor, and a fixing step of fixing the rust-preventive resin bag.

[0009] According to the rust prevention method of the present invention, by directly covering each reinforcing bar with a resin bag containing a rust inhibitor, the bag is kept filled with the rust inhibitor, and the rust prevention effect of the reinforcing bar can be easily improved. By sufficiently preventing rust on the reinforcing bar, the durability and lifespan of the precast concrete are extended, and deterioration of the concrete and repair costs are reduced.

[0010] (2) The above-mentioned method for preventing rust on reinforcing bars is characterized in that the plastic bag has one end open and the other end closed, the distance from one end to the other end corresponding to the length of the exposed reinforcing bar, the covering step includes a process of covering one end of the reinforcing bar with the opening and extending the plastic bag to the other end of the reinforcing bar, and the fixing step includes a process of fixing the opening of the plastic bag.

[0011] According to this rust prevention method, the resin bag is designed with one end open and the other end closed, so that the entire length of the rebar can be covered from one end to the other, thereby preventing rust from being generated on the entire exposed rebar, and minimizing corrosion of the rebar.

[0012] (3) Another method for preventing rust of reinforcing bars according to the present invention provides rust prevention for exposed reinforcing bars in a precast concrete product. The method for preventing rust of reinforcing bars includes a covering step of covering a plurality of reinforcing bars with a resin sheet containing a rust inhibitor, a waterproofing step of further covering the resin sheet with a waterproof sheet, and a fixing step of fixing the rust-preventive resin sheet and the waterproof sheet.

[0013] According to the rust prevention method of the present invention, the rust prevention effect of the reinforcing bar can be easily improved by directly covering the reinforcing bar with a resin sheet containing a rust inhibitor. In addition, by covering the resin sheet with a waterproof sheet, the intrusion of moisture is prevented and the rust inhibitor contained in the resin sheet is prevented from diffusing to the outside, improving the rust prevention effect. As a result, the reinforcing bar part is sufficiently rust-proofed, which extends the durability and lifespan of the precast concrete and reduces the deterioration of the concrete and the repair costs.

[0014] (4) The precast concrete product of the present invention has an exposed reinforcing bar portion, a resin bag covering the reinforcing bar portion, and a fixing member fixing the resin bag to the reinforcing bar portion, and is characterized in that the resin bag contains a rust inhibitor.

[0015] According to the precast concrete product of the present invention, the rust-preventive effect of the reinforcing bars can be easily improved by directly covering the reinforcing bars with resin bags containing the rust inhibitor. By sufficiently preventing rust on the reinforcing bars, the durability and lifespan of the precast concrete are extended, and deterioration of the concrete and repair costs are reduced.

[0016] (5) Another precast concrete product of the present invention has a plurality of exposed reinforcing bar sections, and comprises a resin sheet covering the plurality of reinforcing bar sections, a waterproof sheet covering the resin sheet, and fixing members for fixing the resin sheet and the waterproof sheet to the reinforcing bar sections, wherein the resin sheet contains a rust inhibitor.

[0017] According to the precast concrete product of the present invention, the rust-preventive effect of the reinforcing bars can be easily improved by directly covering the reinforcing bars with a resin sheet containing a rust inhibitor. In addition, by covering the resin sheet with a waterproof sheet, the intrusion of moisture is prevented and the rust inhibitor contained in the resin sheet is prevented from diffusing to the outside, improving the rust-preventive effect. As a result, the reinforcing bars are sufficiently rust-proofed, which extends the durability and lifespan of the precast concrete and reduces deterioration of the concrete and repair costs. Effect of the Invention

[0018] According to the present invention, the use of a resin bag containing a rust inhibitor or a resin sheet containing a rust inhibitor for the reinforcing bars of precast concrete protects the reinforcing bars from rusting, thereby extending the life of the reinforcing bars and improving the durability of the entire structure of the precast concrete construction method. [Brief description of the drawings]

[0019] [Figure 1] 1 is a plan view showing a resin bag including a rust-preventive material according to a first embodiment of the present invention. [Diagram 2] FIG. 1 is a perspective view showing a precast concrete product according to a first embodiment of the present invention. [Diagram 3] FIG. 2 is a side view showing a process of covering a precast concrete structure with a resin bag according to the first embodiment of the present invention. [Figure 4] FIG. 4 is a plan view showing a resin sheet including a rust-preventive material according to a second embodiment of the present invention. [Diagram 5] FIG. 4 is a perspective view showing a precast concrete product according to a second embodiment of the present invention. [Figure 6] FIG. 11 is a front view showing a state in which a resin sheet is covered on a precast concrete structure according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] A precast concrete product 2 according to a first embodiment of the present invention will be described in detail with reference to the drawings.

[0021] As shown in Fig. 1, the resin bag 1 according to the present invention is made of polyethylene (PE) containing a volatile rust inhibitor, and is a long flat-bottomed bag with one end 11 open and the other end 12 closed to form a bottom. In this embodiment, the resin bag 1 is formed by inflation molding a polyethylene tube with a thickness of 0.1 mm. The length of the resin bag 1 corresponds to the length of the exposed reinforcing bars.

[0022] As shown in Fig. 2, a precast concrete product 2 which uses a resin bag 1 for storage has a concrete portion 21 and a reinforcing bar portion 22 exposed from the concrete portion 21. A portion of the reinforcing bar portion 22 is embedded in the concrete portion 21, and another portion is exposed so as to protrude from the concrete portion 21. In this embodiment, there are ten reinforcing bar portions 22, each of which has a roughly cylindrical shape with a diameter of 5 cm and a length of 100 cm.

[0023] As shown in FIG. 3, the resin bags 1 are attached to the precast concrete product 2 in the order of (A) to (D).

[0024] As shown in FIG. 3(A), a resin bag 1 is prepared, the distance from one end 11 to the other end 12 of which corresponds to the length of the exposed reinforcing bar portion 22.

[0025] As shown in FIG. 3(B), the reinforcing bar portion 22 exposed from the open end 11 is covered with a resin bag 1.

[0026] As shown in FIG. 3(C), the resin bag 1 is placed over the reinforcing bar portion 22 until the other closed end is located at the tip of the reinforcing bar portion 22 and the open end 11 reaches the base of the reinforcing bar portion 22.

[0027] 3(D), the resin bag 1 is placed over the reinforcing bar portion 22 of the precast concrete product 2, and the opening of the resin bag 1 is fixed with tape 3 near the base of the reinforcing bar portion 22. This prevents moisture from entering the resin bag 1 and also prevents the rust inhibitor from leaking out.

[0028] In the first embodiment, the embodiment has been described in which the vicinity of the opening of the resin bag 1 is fixed with tape. However, the fixing member for fixing the vicinity of the opening of the resin bag 1 may be a rubber band, a band with Velcro (registered trademark), or any other fixing member that can fix the resin bag 1 to the reinforcing bar portion 22 and prevent the intrusion of moisture and the outflow of the rust inhibitor.

[0029] In the first embodiment, the length of the resin bag 1 corresponds to the length of the exposed rebar. However, the length of the resin bag may be longer than the exposed rebar.

[0030] In the first embodiment, the resin bag 1 has been described as being a flat-bottom bag. However, the resin bag 1 may be a bag of another shape. Also, the resin bag 1 has been described as being formed by inflation molding. However, the resin bag may be formed by another molding method.

[0031] In the first embodiment, the resin bag 1 is described as being shaped to fit the reinforcing bar section, which is roughly cylindrical in shape with a diameter of 5 cm and a length of 100 cm. However, the resin bag can be shaped in various ways so as to adequately cover the reinforcing bar section.

[0032] Next, a precast concrete product 102 according to a second embodiment of the present invention will be described in detail with reference to the drawings.

[0033] As shown in Fig. 4, the resin sheet 101 according to the present invention is made of polyethylene (PE) containing a volatile rust inhibitor, and has a rectangular shape. In this embodiment, the resin sheet 101 is formed by cutting a polyethylene sheet having a thickness of 0.1 mm. The size of the resin sheet 101 corresponds to the precast concrete product 102 and the exposed reinforcing bars 122.

[0034] As shown in Fig. 5, a precast concrete product 102 that uses a resin sheet 101 during storage has a concrete portion 121 and a reinforcing bar portion 122 exposed from the concrete portion 121. A portion of the reinforcing bar portion 122 is embedded in the concrete portion 121, and another portion is exposed so as to protrude from the concrete portion 121. In this embodiment, five reinforcing bar portions 122 are provided, and the exposed portion has a diameter of 5 cm and is in an inverted U-shape.

[0035] As shown in Fig. 6, a precast concrete product 102 has a resin sheet 101 placed over the reinforcing bar portion 122, and is then covered with a waterproof sheet 104. The waterproof sheet 104 is a well-known blue tarp.

[0036] First, a precast concrete product 102 with the reinforcing bar portion 122 exposed is prepared.

[0037] Thereafter, a rectangular resin sheet 101 is placed over the reinforcing bar portion 122 .

[0038] Thereafter, waterproof sheet 104 is placed on the outside of resin sheet 101 so as to fit along resin sheet 101. Waterproof sheet 104 is preferably larger in size than resin sheet 101.

[0039] Thereafter, the resin sheet 101 and the waterproof sheet 104 are fixed with ropes 103 .

[0040] This prevents moisture from penetrating into waterproof sheet 104. In addition, the rust-preventive material diffused from resin sheet 101 is shielded by waterproof sheet 104, and can be prevented from diffusing to the outside of waterproof sheet 104.

[0041] In the second embodiment, the resin sheet 101 and the waterproof sheet 104 are fixed using the rope 103 as a fixing member. However, the fixing member may be another fixing member such as a band as long as it can fix the resin sheet 101 and the waterproof sheet 104 to the precast concrete product 102.

[0042] In the second embodiment, the precast concrete product 102 has been described as having a reinforcing bar section 122 having an exposed portion shaped like an inverted U covered with the resin sheet 101. However, the reinforcing bar section 122 of the precast concrete product 102 may have another shape, and the resin sheet 101 may have another shape and size corresponding to the shapes of the precast concrete product 102 and the reinforcing bar section 122.

[0043] Furthermore, in the first and second embodiments, the resin bag 1 and the resin sheet 101 are described as being made of polyethylene containing a rust inhibitor. However, the resin bag and the resin sheet may contain a rust inhibitor and have a rust prevention function, and may be made of a resin material whose main component is, for example, polypropylene (PP), polyvinyl chloride (PVC), polyphenylene sulfide (PPS), polyether ether ketone (PEEK), or fluororesin.

[0044] In the first and second embodiments, the resin bag 1 and the resin sheet 101 are described as having a single-layer structure. However, the resin bag 1 and the resin sheet 101 may have a multi-layer structure including a layer containing a rust inhibitor and a shielding layer that does not allow the rust inhibitor to pass through.

[0045] In the first and second embodiments, the resin bag 1 and the resin sheet 101 are described as having a thickness of 0.1 mm. However, the resin bag and the resin sheet may have a thickness of 0.05 mm or more, and preferably have a thickness in the range of 0.08 mm to 0.2 mm.

[0046] The above detailed description is intended to provide a specific embodiment of the present invention, and is not intended to limit the scope of the present invention. Various changes and modifications can be made within the scope of the present invention based on the suggestions of the embodiments. Such changes and modifications are also included within the scope of the present invention. [Industrial Applicability]

[0047] The present invention relates to a method for preventing rust on reinforcing bars in a precast concrete product. [Explanation of symbols]

[0048] 1 Plastic bag 2. Precast concrete products 3 Tape (fixing material) 11 One end (opening) 12 Other end (closed) 21 Concrete Section 22 Reinforced concrete 101 Plastic sheet 102 Precast concrete products 103 Rope (fixing member) 104 Tarpaulin 121 Concrete Section 122 Reinforced concrete

Claims

1. A method for preventing rust on exposed reinforcing bars in a precast concrete product, comprising: A covering step of covering each reinforcing bar portion with a resin bag containing a rust inhibitor; and a fixing step of fixing the anti-rust resin bag.

2. The resin bag has an open end and a closed end, and the distance from the open end to the closed end corresponds to the length of the exposed reinforcing bar portion. The covering step includes a step of covering the opening from one end of the reinforcing bar portion and extending the resin bag to the other end of the reinforcing bar portion, The method for preventing rust on reinforcing bars according to claim 1 , wherein the fixing step comprises a process of fixing the opening of the resin bag.

3. A method for preventing rust on exposed reinforcing bars in a precast concrete product, comprising: A covering step of covering the plurality of reinforcing bar portions with a resin sheet containing a rust inhibitor; A waterproofing step of further covering the resin sheet with a waterproof sheet; A method for preventing rust on reinforcing bars, comprising a fixing step of fixing the rust-preventive resin sheet and the waterproof sheet.

4. It has multiple exposed rebar sections, A plastic bag that covers each rebar section; A fixing member is provided for fixing the resin bag to each reinforcing bar portion, A precast concrete product, characterized in that the resin bag contains a rust inhibitor.

5. It has multiple exposed rebar sections, A resin sheet covering the plurality of reinforcing bar portions; A waterproof sheet covering the resin sheet; A fixing member for fixing the resin sheet and the waterproof sheet to the reinforcing bar portion, A precast concrete product, characterized in that the resin bag contains a rust inhibitor.

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