Ambient temperature repair material

Abstract

To provide an ambient temperature repair material that contains waste cooking oil, has excellent workability, and also has excellent strength, bendability, aggregate scattering resistance, and durability.SOLUTION: An ambient temperature repair material according to the present invention contains an aggregate, asphalt, cement, and a fatty acid, and further contains a waste cooking oil and hydroxystearic acid. Furthermore, it is preferable that the ambient temperature repair material according to the present invention has a mass ratio of a fatty acid content to a waste cooking oil content of 80 to 99:20 to 1. In addition, it is preferable that the ambient temperature repair material according to the present invention contains 1.0 to 5.0 pts.mass of hydroxystearic acid when the sum of the fatty acid content and the waste cooking oil content is 100 pts.mass.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a room temperature repair material. [Background technology]

[0002] In order to repair locally damaged areas in existing road pavements, cold repair materials (cold asphalt mixtures) that can be applied at room temperature are used. Regarding room temperature repair materials, various techniques have been proposed, as shown below. For example, Patent Document 1 proposes a soft asphalt mixture characterized by containing 30 to 150 parts by weight of linseed oil fatty acid and / or linseed oil fatty acid ester per 100 parts by weight of soft asphalt having a penetration of more than 80 and not more than 300. Furthermore, Patent Document 2 proposes a method for producing a paving binder, which is characterized in that a raw material containing at least one of vegetable-derived oils, waste oils of the vegetable-derived oils, edible animal fats and oils, and waste materials of the edible animal fats and oils are polymerized by at least one of polymerization, condensation, and crosslinking to obtain a paving binder. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5939722 [Patent Document 2] JP 2013-72078 A Summary of the Invention [Problem to be solved by the invention]

[0004] Currently, waste oil as industrial waste is seen as a problem, and the amount of waste oil discharged is increasing year by year. Therefore, in order to realize a carbon-neutral society, technological development is being promoted, such as the production of aviation fuel (SAF: Sustainable Aviation Fuel) from waste cooking oil. In order to actively promote the 3Rs (Reduce, Reuse, Recycle) in the construction industry, the inventors conducted a detailed study on the use of waste cooking oil in cold repair materials as proposed in Patent Documents 1 and 2. As a result, the inventors confirmed that the inclusion of waste edible oil in a room-temperature repair material significantly reduces "workability (applicability)." Furthermore, the inventors wanted to ensure the material properties required for a room-temperature repair material, such as "strength," "flexibility," "aggregate scattering resistance," and "durability," while including waste edible oil in the room-temperature repair material, and further to improve these material properties.

[0005] From this perspective, an object of the present invention is to provide a room-temperature repair material which contains waste edible oil, has excellent workability, strength, flexibility, aggregate scattering resistance, and durability. [Means for solving the problem]

[0006] The above problems can be solved by the following measures. The room-temperature repair material according to the present invention is a room-temperature repair material containing aggregate, asphalt, cement, and a fatty acid, and further containing waste edible oil and hydroxystearic acid. According to the present invention, the room temperature repair material contains hydroxystearic acid in addition to waste cooking oil, and therefore the viscosity is improved, resulting in excellent workability. Also, according to the present invention, the room temperature repair material contains hydroxystearic acid in addition to waste cooking oil, and therefore the waste cooking oil is retained inside the room temperature repair material (oil leakage is suppressed), resulting in excellent strength, flexibility, aggregate scattering resistance, and durability. In the room-temperature repair material according to the present invention, the content of the fatty acid and the content of the waste edible oil are preferably in a mass ratio of 80-99:20-1. According to the present invention, by specifying the ratio between the fatty acid content and the waste edible oil content, it is possible to more reliably achieve excellent strength, flexibility, aggregate scattering resistance, and durability. In the room temperature repair material according to the present invention, the content of the hydroxystearic acid is preferably 1.0 to 5.0 parts by mass, where the total of the content of the fatty acid and the content of the waste edible oil is taken as 100 parts by mass. According to the present invention, the content of hydroxystearic acid is specified, so that the workability, strength, flexibility, aggregate scattering resistance, and durability can be further reliably improved. Effect of the Invention

[0007] The room-temperature repair material according to the present invention contains waste edible oil and yet is excellent in workability, strength, flexibility, aggregate scattering resistance, and durability. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment (the present embodiment) for carrying out the room-temperature repair material according to the present invention will be described. [Room temperature repair material] The room temperature repair material according to this embodiment contains aggregate, asphalt, cement, and fatty acid, and further contains waste edible oil and hydroxystearic acid. As mentioned above, "room temperature repair material" is a material used to repair locally damaged areas in existing road pavements, etc., and is a material that can be applied at room temperature. It is also called room temperature asphalt mixture or room temperature composite material. Hereinafter, each element constituting the room temperature repair material according to this embodiment will be described.

[0009] (aggregate) The aggregate is preferably a coarse aggregate, a fine aggregate, and a filler, and has a continuous grain size. The coarse aggregate is a known one such as crushed stone, crushed balls, gravel, and steel slag. In addition, artificially fired aggregate, fired foamed aggregate, artificial lightweight aggregate, ceramic grains, and emery can also be used. The fine aggregate is a known one such as natural sand, artificial sand, and screenings. The filler is stone powder made by crushing limestone or other rocks, crushed sand, slaked lime, cement, recovered dust, or fly ash. And the crushed stone and crushed sand are as specified in JIS A5005:2020. The maximum particle size of the aggregate is appropriately selected from approximately 2.5mm to 15mm depending on the conditions of use. For example, if the repair area (hole, etc.) is shallow or thin, a relatively small particle size of 2.5mm can be used as the maximum particle size. If the object to be repaired is larger than a certain size, a particle size of 5mm can be used as the maximum particle size. Furthermore, if permeability is required, a large particle size of approximately 15mm can be used as the maximum particle size.

[0010] (asphalt) Asphalt includes straight asphalt, blown asphalt, and asphalt for waterproofing work, and is defined in JIS K 2207-1996. The asphalt content in the room temperature repair material is, relative to 100 parts by mass of aggregate, preferably 1 part by mass or more, 3 parts by mass or more, or 4 parts by mass or more, and preferably 15 parts by mass or less, 12 parts by mass or less, or 10 parts by mass or less.

[0011] (cement) Cement includes portland cement (JIS R 5210:2009), blast furnace cement (JIS R 5211:2009), silica cement (JIS R 5212:2009), fly ash cement (JIS R 5213:2009), ecocement (JIS R 5214:2009), etc. The cement content in the room temperature repair material is, relative to 100 parts by mass of aggregate, preferably 0.5 parts by mass or more, 1 part by mass or more, or 2 parts by mass or more, and preferably 10 parts by mass or less, 8 parts by mass or less, or 5 parts by mass or less.

[0012] (fatty acid) The fatty acid is a monovalent carboxylic acid of a long-chain hydrocarbon, and is not particularly limited, but examples thereof include palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, etc., and is composed of one or more kinds. In addition, as the fatty acid, any known fatty acid used in general room temperature repair materials may be used, and soybean-derived fatty acids may also be used.

[0013] (Waste cooking oil) Waste edible oil is edible oil (animal or vegetable oil) that has been used or discarded due to expiration date, etc. Examples of waste edible oil include, but are not limited to, discarded frying oil for frying food. Because the room temperature repair material contains waste cooking oil, it is possible to utilize discarded waste cooking oil, thereby contributing to the realization of a carbon-neutral society.

[0014] (Fatty acid content and waste cooking oil content) The mass ratio of the fatty acid content to the waste cooking oil content in the room temperature repair material is preferably 80-99:20-1, and more preferably 90-93:10-7. By setting the mass ratio of the fatty acid to the waste cooking oil within a predetermined range, it is possible to obtain the effect of reducing carbon dioxide emissions due to the use of the waste cooking oil, while at the same time making each property (strength, flexibility, aggregate scattering resistance, durability) excellent. In addition, the total content of the fatty acids and the waste cooking oil in the room temperature repair material is, when the asphalt content is 100 parts by mass, preferably 50 parts by mass or more, 60 parts by mass or more, or 70 parts by mass or more, and is preferably 90 parts by mass or less, 85 parts by mass or less, or 80 parts by mass or less.

[0015] (Hydroxystearic acid) Hydroxystearic acid, specifically, is 12-hydroxystearic acid, which is a saturated fatty acid having an asymmetric hydroxyl group at the 12th carbon of stearic acid. By containing hydroxystearic acid, the room temperature repair material can have excellent workability, strength, flexibility, aggregate scattering resistance, and durability even if it contains the above-mentioned waste edible oil. The content of hydroxystearic acid in the room temperature repair material is, when the total of the fatty acid content and the waste cooking oil content is 100 parts by mass, preferably 1.0 parts by mass or more, 1.5 parts by mass or more, and preferably 5.0 parts by mass or less, 4.0 parts by mass or less, or 3.0 parts by mass or less.

[0016] [Manufacturing method of room temperature repair material] In the manufacturing method of the room temperature repair material according to the present embodiment, first, aggregate is stirred, and then asphalt is added and mixed. Then, the mixture of fatty acid and waste edible oil, hydroxystearic acid and cement (and other additives as necessary) are added and mixed to manufacture the room temperature repair material. In addition, it is preferable to carefully manage the mixing time during each mixing process to prevent overmixing. The cold repair material produced by the above-mentioned method is stored and transported in bags, and is sold in the bags.

[0017] [Repair method using room temperature repair materials] The repair method using the room-temperature repair material according to this embodiment includes a filling step, a watering step, and a compaction step. The filling process is a process in which cold repair material is filled into repair locations (holes, etc.) that have appeared on the asphalt road surface. The cold repair material is filled manually by workers using a shovel or similar tool from a bag. The amount of cold repair material filled should be enough to raise the material slightly above the road surface. In addition, if there are many areas to be repaired or the repairs are large, heavy machinery may be used to fill the holes instead of doing it by hand.

[0018] The watering process is a process in which water is sprayed onto the cold repair material that has been filled into the repair area. The watering is done manually by a worker using a watering nozzle. The amount of water sprayed is, for example, 1.5 liters or more for a mass of 20 kg of cold repair material.

[0019] The compaction process is a process in which the sprayed cold repair material is compressed to make the road surface even. Compaction is performed by hitting the surface of the cold repair material with a shovel or by using a compactor. After compaction, the cold repair material is cured for a specified period of time to harden. EXAMPLES

[0020] [Example 1: Examination of the ratio of fatty acids to waste cooking oil] (Preparation of each sample in Table 1) Samples 1-1 to 1-3 (room temperature repair materials) containing aggregate, asphalt, cement, and further fatty acid and waste edible oil in the mass ratios shown in Table 1 were prepared. In each of Samples 1-1 to 1-3, the amount of asphalt added was 4 parts by mass and the amount of cement added was 3 parts by mass when the aggregate was 100 parts by mass. In each of Samples 1-1 to 1-3, the total amount of fatty acid and waste edible oil added was 75 parts by mass when the asphalt was 100 parts by mass.

[0021] (Test content: Room temperature Marshall stability test) Hydration was carried out on the samples (room temperature repair materials) prepared using the above method to prepare test specimens. After 30 minutes of curing at 20°C after hydration, a Marshall stability test was carried out at a test temperature of 20°C to measure stability (KN) and flow (1 / 100cm). Other conditions in the Marshall stability test were in accordance with "B001 Marshall stability test method" described in the Pavement Evaluation and Test Method Handbook (compiled by the Japan Road Association). The pass standard for "strength" was a stability (KN) of 6.0 or more, and the pass standard for "flexibility" was a flow (1 / 100 cm) of 15 to 40.

[0022] (Test content: Cantabro test) Hydration was carried out on the samples (room temperature repair materials) prepared using the above method to prepare test specimens. After 30 minutes of curing at 20°C after hydration, a Cantabro test was carried out at a test temperature of 20°C to measure the loss rate (%). Other conditions in the Cantabro test were in accordance with 1.5.6 Performance test of emergency repair materials (room temperature mixtures) described in the Pavement Design and Construction Guidelines (edited by Metropolitan Expressway Company Limited). The pass standard for "aggregate scattering resistance" was a loss rate (%) of 20.0 or less.

[0023] (Test content: Low speed wheel tracking test) Hydration was carried out on the samples (room temperature repair materials) prepared using the above method, and test specimens were prepared. After 30 minutes of curing at 20°C after hydration, a low-speed wheel tracking test was carried out at a test temperature of 20°C, and the dynamic stability (revolutions / mm) and settlement (mm) were measured. Other conditions for the low-speed wheel tracking test were in accordance with 1.5.6 Performance test of emergency repair materials (room temperature mixtures) described in the Pavement Design and Construction Guidelines (edited by Metropolitan Expressway Company Limited). The passing standard for "durability" was a dynamic stability (times / mm) of 3,000 or more.

[0024] [Table 1]

[0025] (Discussion of the results in Table 1) According to the results in Table 1, all of the material properties of Samples 1-1 to 1-3 satisfied the pass criteria (quality target values), but Sample 1-2, which had a small loss rate and high dynamic stability, was determined to be the most preferable.

[0026] [Example 2: Study of basic composition] (Preparation of each sample in Table 2) Basically, the sample was the same as that in Example 1, except for the following points. In the sample shown as "general purpose mix" in Table 2, the amount of asphalt added was 7 parts by mass and the amount of cement added was 2 parts by mass, relative to 100 parts by mass of aggregate. In the sample shown as "cold climate type mix" in Table 2, the amount of asphalt added was 7 parts by mass and the amount of cement added was 5 parts by mass per 100 parts by mass of aggregate. In all samples, the mass ratio of fatty acids to waste cooking oil was 93:7.

[0027] (Test Contents) Basically, the test contents were the same as those in Example 1, except for the following points. For samples marked with a "Test temperature" of "-5°C" in Table 2, the samples were cured at -5°C for 60 minutes after adding water, and then each test was carried out at a test temperature of -5°C.

[0028] [Table 2]

[0029] (Discussion of the results in Table 2) According to the results in Table 2, all of the material properties of samples 2-1 to 2-3 met the pass criteria (quality target values), but since an oil film was generated when water was added, it was determined that measures to suppress the oil film were necessary.

[0030] [Example 3: Study of workability by adding hydroxystearic acid] (Preparation of each sample in Table 3) Basically, the sample was the same as that in Example 1, except for the following points. The amount of hydroxystearic acid shown in Table 3 was added at the same time as the cement was added. In all samples, the mass ratio of fatty acids to waste cooking oil was 93:7.

[0031] (Test content: Workability test) Seven panelists evaluated the samples (room-temperature repair materials) prepared using the above method on three levels (○, △, ×) for "handling," "clumping," "sagging," and "rakeability" based on the following criteria. For samples where the ratings were divided, a majority vote was used, and the rating given by the largest number of people was considered the final rating.

[0032] "Handling" was an evaluation of whether the sample was difficult to handle when scooped with a shovel, with samples that were easy to handle being rated as "○", samples that were neither difficult nor easy to handle being rated as "△", and samples that were difficult to handle being rated as "×". "Lumpiness" is an evaluation of the degree to which lumps (clumps) occurred in the sample, with a rating of "O" indicating that almost no lumps occurred, a rating of "△" indicating that a few lumps occurred, and a rating of "X" indicating that many lumps occurred. "Dropping" was an evaluation of whether the material separated and caused the sample to stick to the bag when placed in the bag. If there was almost no sticking to the bag, it was rated as "○", if there was some sticking to the bag, it was rated as "△", and if there was a lot of sticking to the bag, it was rated as "×". "Rakeability" is an evaluation of whether or not the sample can be leveled using a rake or a dragonfly. If the sample was easy to level, it was rated as "○", if it was neither easy nor difficult to level, it was rated as "△", and if it was difficult to level, it was rated as "×". For the "overall evaluation," a score of 3 points was assigned for each of the evaluation items of handling, clumping, sagging, and rakeability, a score of 3 for ○, 2 points for △, and 1 point for ×, and the total score was calculated.

[0033] [Table 3]

[0034] (Discussion of the results in Table 3) According to the results in Table 3, it was confirmed that Samples 3-2 and 3-3, in which hydroxystearic acid was added, had significantly improved workability compared to Sample 3-1. In addition, in Samples 3-2 and 3-3, the generation of an oil film when water was added, which was a problem in Example 2, was also suppressed.

[0035] [Example 4: Examination of material properties by adding hydroxystearic acid] (Preparation of each sample in Table 4) Basically, the sample was the same as that in Example 1, except for the following points. The amount of hydroxystearic acid shown in Table 4 was added at the same time as the cement was added. In all samples, the mass ratio of fatty acids to waste cooking oil was 93:7.

[0036] (Test Contents) The test contents were the same as those in Example 1.

[0037] [Table 4]

[0038] (Discussion of the results in Table 4) According to the results in Table 4, all of the material properties of Samples 4-1 to 4-4 met the pass criteria (quality target values). However, taking into consideration the results of Example 3 described above, it was determined that Sample 4-1, which does not contain hydroxystearic acid, does not exhibit excellent workability. Based on the results in Table 4, it was determined that, among Samples 4-2 and 4-3, the results of Sample 4-2, in which the content of hydroxystearic acid was 1.5 parts by mass, were particularly preferable.

Claims

1. A cold repair material containing aggregate, asphalt, cement, and fatty acid, A room temperature repair material further comprising waste edible oil and hydroxystearic acid.

2. 2. The room temperature repair material according to claim 1, characterized in that the content of the fatty acid and the content of the waste cooking oil are in a mass ratio of 80-99:20-1.

3. The room temperature repair material according to claim 1 or 2, characterized in that the content of the hydroxystearic acid is 1.0 to 5.0 parts by mass when the total of the content of the fatty acid and the content of the waste cooking oil is 100 parts by mass.

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