JP2019143046A - Ordinary temperature asphalt mixture, hydrogenated ordinary temperature asphalt mixture, and manufacturing method of ordinary temperature asphalt mixture - Google Patents

Abstract

To provide an ordinary temperature asphalt capable of providing a hydrogenated ordinary temperature asphalt mixture high in adhesiveness and high in Marshall stability even when a road surface is wet, the hydrogenated ordinary temperature asphalt mixture high in adhesiveness and high in Marshall stability even when a road surface is wet, and a manufacturing method of the ordinary temperature asphalt mixture capable of effectively manufacturing the ordinary temperature asphalt mixture.SOLUTION: An ordinary temperature asphalt mixture contains an aggregate, asphalt, a surfactant containing at least oleic acid and an alkali additive, in which the oleic acid is contained at 60.0 to 66.5 mass% in 100 mass% of the surfactant. The hydrogenated ordinary temperature asphalt mixture contains the ordinary temperature asphalt mixture and water.SELECTED DRAWING: None

Description

  The present invention relates to a room temperature asphalt mixture, a water-added room temperature asphalt mixture, and a method for producing a room temperature asphalt mixture.

  The heated asphalt mixture has excellent durability and is widely used for general road pavement and the like. The heated asphalt mixture is suitable for mass production and use because it requires heating.

  However, the heated asphalt mixture is not economical and suitable for applications that require a small amount of production and use, such as repairing such as filling a paved road. In addition, the heated asphalt mixture becomes more viscous when the mixture temperature is lowered, and the construction becomes difficult. Furthermore, when the road surface is wet, such as a road during rain or a puddle portion of the road, the heated asphalt mixture is deteriorated in adhesiveness and difficult to construct.

  On the other hand, Patent Document 1 discloses a normal temperature construction type asphalt mixture containing asphalt, aggregate, tall oil fatty acid and cement, and having a weight ratio of tall oil fatty acid to cement of 100: 10 to 100: 300. It is disclosed. According to the room temperature construction type heated asphalt mixture of Patent Document 1, room temperature construction at 100 ° C. or lower with the road surface wet is possible.

  Patent Document 2 discloses an asphalt mixture containing aggregate, asphalt, a lubricant solidifying material, and an alkaline additive, and the lubricant solidifying material contains 39 to 59% by weight of oleic acid. According to the asphalt mixture of Patent Document 2, normal temperature construction at 100 ° C. or lower with the road surface wet is possible.

  Patent Document 3 discloses an asphalt mixture containing aggregate, asphalt, a lubricious solidifying material, and an alkaline additive, and the lubricious solidifying material contains 67 to 85% by weight of oleic acid. According to the asphalt mixture of Patent Document 3, normal temperature construction at 100 ° C. or lower with the road surface wet is possible.

Japanese Patent No. 5582978 Japanese Patent No. 5916937 Japanese Patent No. 5916938

  However, the normal temperature construction type heated asphalt mixture of Patent Document 1 and the asphalt mixtures of Patent Documents 2 and 3 have a problem that the Marshall stability and the dynamic stability are not sufficiently high. Moreover, the normal temperature construction-type heating asphalt mixture of Patent Document 1 and the asphalt mixtures of Patent Documents 2 and 3 have a problem that the adhesiveness when the road surface is wet is not sufficiently high.

  The present invention has been made in view of the above circumstances, and a room temperature asphalt mixture that provides a water-added room temperature asphalt mixture that has high adhesion and high marshall stability and dynamic stability even when the road surface is wet. It is an object of the present invention to provide a water-added room temperature asphalt mixture having high adhesiveness and high marshall stability and dynamic stability even when wet, and a method for producing a room temperature asphalt mixture capable of efficiently producing a room temperature asphalt mixture.

  The room temperature asphalt mixture according to the first aspect of the present invention includes aggregate, asphalt, a surfactant containing at least oleic acid, and an alkaline additive, and the oleic acid is 100% by mass of the surfactant. 60.0-66.5 mass% is contained in, It is characterized by the above-mentioned.

  The water-added room temperature asphalt mixture according to the second aspect of the present invention includes the room temperature asphalt mixture and water.

  A method for producing a room temperature asphalt mixture according to a third aspect of the present invention is a method for producing the room temperature asphalt mixture, comprising mixing 100-120 ° C. aggregate and 150-180 ° C. asphalt. A first mixing step for obtaining a first mixture; a second mixing step for mixing the first mixture with a surfactant containing oleic acid to obtain a second mixture; the second mixture; and an alkaline additive; A third assembling step to obtain a third mixture by mixing the oleic acid in 100% by mass of the surfactant with 60.0-66.5% by mass of the resulting normal temperature asphalt mixture. It is characterized by.

  According to the present invention, a room temperature asphalt mixture from which a water-added room temperature asphalt mixture with high adhesion and high Marshall stability and dynamic stability is obtained even when the road surface is wet, high adhesiveness even when the road surface is wet and It is possible to provide a water-added room temperature asphalt mixture having high Marshall stability and dynamic stability, and a method for producing a room temperature asphalt mixture capable of efficiently producing a room temperature asphalt mixture.

  Hereinafter, the manufacturing method of the normal temperature asphalt mixture which concerns on this embodiment, a water addition normal temperature asphalt mixture, and a normal temperature asphalt mixture is demonstrated.

[Normal temperature asphalt mixture]
The room temperature asphalt mixture according to the present embodiment includes aggregate, asphalt, a surfactant containing oleic acid, and an alkaline additive. Moreover, in the normal temperature asphalt mixture which concerns on this embodiment, the mixture which consists of an aggregate, asphalt, and surfactant is defined as a mixture before alkali addition. For this reason, the normal temperature asphalt mixture which concerns on this embodiment contains the mixture before an alkali addition, and an alkaline additive. Furthermore, in the normal temperature asphalt mixture according to the present embodiment, a mixture composed of asphalt and a surfactant is defined as a binder mixture. For this reason, the normal temperature asphalt mixture which concerns on this embodiment contains an aggregate, a binder mixture, and an alkaline additive. Moreover, the mixture containing the normal temperature asphalt mixture and water which concern on this embodiment is defined as a water addition normal temperature asphalt mixture.

(aggregate)
The aggregate is not particularly limited, and a known aggregate for a normal temperature asphalt mixture can be used. Specifically, coarse aggregate, fine aggregate, and filler can be used as the aggregate. Here, the coarse aggregate is an aggregate that remains on the 2.36 mm sieve. A fine aggregate is an aggregate that permeates through a 2.36 mm sieve and remains on the 0.075 mm sieve. A filler is a mineral powder that passes through a 0.60 mm sieve.

  As the coarse aggregate, for example, crushed stone, crushed stone, gravel, or steel slag can be used. For example, No. 7 crushed stone can be used as the crushed stone. Moreover, natural sand, artificial sand, and screenings can be used as the fine aggregate. For example, sand such as coarse sand and fine sand can be used. As the filler, for example, stone powder that is a powder of limestone can be used. Recycled aggregate or the like can be used as the coarse aggregate and the fine aggregate.

(asphalt)
As the asphalt, a known one that is usually used in a normal temperature asphalt mixture can be used. As the asphalt, for example, straight asphalt 60/80 or the like is used. As the asphalt, modified asphalt or the like can be used.

  Asphalt is usually contained in 2 to 10% by mass, preferably 4 to 9.5% by mass, more preferably 4 to 7% by mass, and further preferably 4 to 5% by mass in 100% by mass of the mixture before alkali addition. . It is preferable that the asphalt content is within the above range because sufficient Marshall stability and dynamic stability can be obtained.

(Surfactant)
The surfactant used in the present embodiment includes a carboxylic acid, and includes at least oleic acid among the carboxylic acids. The surfactant used in the present embodiment reacts quickly with calcium hydroxide generated from an alkaline additive in the presence of water, thereby producing a thickener that quickly thickens the normal temperature asphalt mixture. Have. The main component of the thickener is assumed to be calcium dicarboxylate (RCOO) ₂ Ca such as calcium dioleate as described later.

  Thus, the room temperature asphalt mixture according to this embodiment quickly generates a thickener in the presence of water. Therefore, according to the room temperature asphalt mixture according to the present embodiment, when the room temperature asphalt mixture pavement is constructed using the water-added room temperature asphalt mixture obtained in the presence of water, the strength of the water addition room temperature asphalt mixture is rapidly increased. It becomes possible to release traffic early.

  Note that the thickening of the room temperature asphalt mixture according to the present embodiment in the presence of water, that is, the thickening of the water-added room temperature asphalt mixture containing the room temperature asphalt mixture and water, the components in the alkaline additive, the surfactant, This is presumably due to the saponification reaction. Specifically, the thickening of the water-added room temperature asphalt mixture is presumed to be due to the saponification reaction between the calcium hydroxide produced by the reaction of the calcium compound in the alkaline additive with water and the surfactant. The presumed mechanism is shown below.

First, in a water-added room temperature asphalt mixture, it is presumed that a reaction represented by the following formula (1) that generates calcium hydroxide occurs by a reaction between a calcium compound in an alkaline additive and water.
[Chemical 1]
CaO + H ₂ O → Ca (OH) ₂ (1)

Next, in a water-added room temperature asphalt mixture, it is presumed that calcium hydroxide and a surfactant cause a saponification reaction of the following formula (2). In Formula (2), RCOOH is a component contained in the surfactant used in the present embodiment, and R represents an alkyl group.
[Chemical 2]
2RCOOH + Ca (OH) ₂ → (RCOO) ₂ Ca + 2H ₂ O (2)

The room temperature asphalt mixture according to this embodiment is presumed to be thickened by calcium dicarboxylate (RCOO) ₂ Ca generated by the formula (2).

In addition, the surfactant used in this embodiment includes at least oleic acid CH ₃ (CH ₂ ) ₇ CH═CH (CH ₂ ) ₇ COOH. For this reason, in a water-added room-temperature asphalt mixture, at least calcium dioleate [CH ₃ (CH ₂ ) ₇ CH═CH (CH ₂ ) ₇ COO] ₂ Ca, which is (RCOO) ₂ Ca of oleic acid, is rapidly generated. Guessed.

  In the present embodiment, when the surfactant contains a specific amount of oleic acid, the mechanical strength is quickly developed, so it is presumed that calcium dioleate rapidly thickens the water-added room temperature asphalt mixture.

  The surfactant used in the present embodiment can include, for example, saturated fatty acids such as palmitic acid and stearic acid, unsaturated fatty acids such as linoleic acid and linolenic acid, and the like as carboxylic acids other than oleic acid.

  The oleic acid contained in the surfactant may be added as oleic acid as a chemical substance, but may be derived from animal fat or vegetable fat containing oleic acid. Examples of animal fats containing oleic acid include beef tallow and pork oil. In the case where the animal fat is beef tallow, for example, 100 g beef tallow containing 77.7 g oleic acid is known. It is preferable that the surfactant contains beef tallow because it is easy to adjust the content of oleic acid in the surfactant within the preferable range described later, is inexpensive, and is easy to handle.

  Examples of vegetable fats containing oleic acid include olive oil, safflower oil, sunflower oil, peanut oil, almond oil and the like. When the vegetable fat containing oleic acid is, for example, vegetable oil, it is known that 54.6 g of oleic acid is contained in 100 g of vegetable oil. It is preferable that the surfactant contains vegetable oil because it is easy to adjust the content of oleic acid in the surfactant within the preferable range described later, is inexpensive, and is easy to handle.

  As long as the conditions containing at least oleic acid are satisfied, the surfactant is one or more of the above-mentioned oleic acid, carboxylic acids other than oleic acid, animal fat containing oleic acid, vegetable fat containing oleic acid Can be used in combination.

  In the room temperature asphalt mixture according to this embodiment, oleic acid is contained in 60.0 to 66.5% by mass, preferably 61.5 to 66.5% by mass, in 100% by mass of the surfactant. When the content of oleic acid in the surfactant is within the above range, a water-added room temperature asphalt mixture having high Marshall stability and dynamic stability is obtained, and a high degree of compaction is obtained even at a low temperature, which is preferable. .

  When the surfactant is composed of two or more substances, the content of oleic acid in the surfactant is the sum of the contents of oleic acid in each substance constituting the surfactant, and the mass of the entire surfactant. Calculated by dividing by.

  In the normal temperature asphalt mixture which concerns on this embodiment, when surfactant contains beef tallow, beef tallow is 25-60 mass% in 100 mass% of surfactant, for example, Preferably it is 28-55 mass%, More preferably, it is 30-50. Mass% is included. When the beef tallow content in the surfactant is within the above range, the content of oleic acid in the surfactant is within the above preferred range, so that water addition with high Marshall stability and dynamic stability is achieved. A normal temperature asphalt mixture is obtained, and a high degree of compaction is obtained even at a low temperature, which is preferable.

  In the normal temperature asphalt mixture according to the present embodiment, the surfactant is usually 0.6 to 3.0% by mass, preferably 1 in 100% by mass of the mixture before alkali addition composed of aggregate, asphalt and surfactant. .35 to 2.7% by mass, more preferably 1.5 to 2.1% by mass. A surfactant content in the above range is preferable because a water-added room-temperature asphalt mixture having high Marshall stability and dynamic stability can be obtained, and a high degree of compaction can be obtained even at a low temperature.

(Alkaline additive)
The alkaline additive used in the present embodiment rapidly increases the viscosity of the water-added room temperature asphalt mixture by the rapid reaction between calcium hydroxide generated from the alkaline additive and the surfactant in the presence of water. Has an effect. Thereby, according to the room temperature asphalt mixture according to the present embodiment, when the room temperature asphalt mixture pavement is constructed using the water addition room temperature asphalt mixture obtained in the presence of water, the strength of the water addition room temperature asphalt mixture is quickly increased. It becomes possible to release traffic early. Since the thickening action of the normal temperature asphalt mixture by the reaction between the calcium hydroxide produced from the alkaline additive and the surfactant has been described in the section “Surfactant”, the description is omitted.

  The alkaline additive used in the present embodiment contains at least a calcium compound, for example, calcium oxide CaO. It is considered that when the alkaline additive contains at least a calcium compound, the reaction of the above formula (1) occurs in the presence of water, the reaction of the above formula (2) occurs, and the water-added room temperature asphalt mixture rapidly thickens. It is done.

  The alkaline additive used in the present embodiment is not particularly limited as long as it contains a calcium compound. As an alkaline additive used in the present embodiment, for example, ordinary Portland cement is used. Of these, ordinary Portland cement is preferred because the water-added room temperature asphalt mixture quickly thickens.

Ordinary portland cement, as the main material, tricalcium silicate (3CaO · _SiO 2), dicalcium silicate (2CaO · _SiO 2), calcium aluminate _{(3CaO · Al 2 O 3)} , calcium alumino ferrite (4CaO · Al ₂ O ₃ .Fe ₂ O ₃ ), calcium sulfate (CaSO ₄ .2H ₂ O), and calcium oxide CaO. For this reason. When ordinary Portland cement is used as the alkaline additive, the reaction of the above formula (1) occurs in the presence of water, and the reaction of the above formula (2) occurs, so that the water-added room temperature asphalt mixture quickly thickens. it is conceivable that.

  In the room temperature asphalt mixture according to the present embodiment, the alkaline additive / surfactant mass ratio obtained by dividing the mass of the alkaline additive by the mass of the surfactant is usually 20 to 100% by mass, preferably 30 to 100%. It is 50 mass%, More preferably, it is 50-75 mass%. It is preferable that the alkaline additive / surfactant mass ratio is within the above range because a water-added room temperature asphalt mixture having high Marshall stability can be obtained.

  In the room temperature asphalt mixture according to the present embodiment, the alkaline additive is usually 0.3 to 2.0 parts by mass, preferably 100 parts by mass of the mixture before addition consisting of aggregate, asphalt and surfactant, preferably 0.4 to 1.5 parts by mass are blended. When the blending amount of the alkaline additive is within the above range, a water-added room temperature asphalt mixture having high Marshall stability is obtained, which is preferable.

  In the room temperature asphalt mixture according to the present embodiment, the binder mixture composed of asphalt and a surfactant is usually 3.5 to 8.0% by mass, preferably 4.5 to 7% in 100% by mass of the mixture before alkali addition. Mass% is included. When the blending amount of the binder mixture is within the above range, a water-added room temperature asphalt mixture having high Marshall stability and dynamic stability is preferable.

(Operation of normal temperature asphalt mixture)
The room temperature asphalt mixture according to the present embodiment rapidly thickens in the presence of water. Moreover, since the water addition normal temperature asphalt mixture which is a mixture containing the normal temperature asphalt mixture and water which concerns on this embodiment contains water, it thickens rapidly. For this reason, according to the room temperature asphalt mixture according to the present embodiment, when the room temperature asphalt mixture pavement is constructed using the water-added room temperature asphalt mixture obtained in the presence of water, the water-added room temperature asphalt mixture is rapidly strengthened. Therefore, it becomes possible to release the traffic in the room temperature asphalt mixture pavement at an early stage.

  In addition, it is estimated that the mechanism by which the water-added room temperature asphalt mixture quickly thickens is as follows. That is, when the normal temperature asphalt mixture is brought into contact with water in the presence of water, the reaction of the above formula (1) or the like first occurs, and the alkaline additive generates calcium hydroxide. Examples of the contact state between the room temperature asphalt mixture and water include mixing of the room temperature asphalt mixture and water, penetration of water from the surface of the room temperature asphalt mixture into the room temperature asphalt mixture, and the like. The contact between the cold asphalt mixture and water may or may not be intentional. Examples of intentional contact between the normal temperature asphalt mixture and water include mixing of the normal temperature asphalt mixture with water. The unintentional contact between the room temperature asphalt mixture and the water includes, for example, construction of the room temperature asphalt mixture on a wet road surface or rainy weather.

Next, the calcium hydroxide and the surfactant generate a saponification reaction such as the above formula (2) to generate (RCOO) ₂ Ca that thickens the water-added room temperature asphalt mixture. Since the surfactant used in this embodiment contains a predetermined amount of oleic acid CH ₃ (CH ₂ ) ₇ CH═CH (CH ₂ ) ₇ COOH, a water-added room temperature asphalt mixture is obtained by a saponification reaction such as the above formula (2). Among them, a predetermined amount of calcium dioleate [CH ₃ (CH ₂ ) ₇ CH═CH (CH ₂ ) ₇ COO] ₂ Ca is produced.

  The generated calcium dioleate is presumed to quickly increase the viscosity of the water-added room temperature asphalt mixture and to quickly increase the Marshall stability and dynamic stability of the water-added room temperature asphalt mixture. For this reason, when constructing a room-temperature asphalt mixture pavement using a water-added room-temperature asphalt mixture, it becomes possible to release traffic in the room-temperature asphalt mixture pavement at an early stage.

  Moreover, as for the normal temperature asphalt mixture which concerns on this embodiment, the water addition normal temperature asphalt mixture obtained in presence of water thickens rapidly.

(Effect of room temperature asphalt mixture)
In the room temperature asphalt mixture according to the present embodiment, the water-added room temperature asphalt mixture obtained in the presence of water quickly and thickly increases in viscosity. For this reason, according to the normal temperature asphalt mixture which concerns on this embodiment, even if the road surface is wet, the water addition normal temperature asphalt mixture with high adhesiveness and high Marshall stability is obtained. Moreover, according to the normal temperature asphalt mixture which concerns on this embodiment, a normal temperature asphalt mixture paving body with a high viscosity and high durability can be formed in a short time regardless of whether or not the road surface is wet. For this reason, according to the room temperature asphalt mixture which concerns on this embodiment, the traffic in a room temperature asphalt mixture pavement can be released early regardless of the presence or absence of the road surface.

[Water-added room temperature asphalt mixture]
As described above, the room temperature asphalt mixture according to the present embodiment is thickened quickly and with a high viscosity by the water-added room temperature asphalt mixture obtained in the presence of water. In addition, the water-added room temperature asphalt mixture is thickened due to consumption of water after the contact between the room temperature asphalt mixture and water. For this reason, the amount of water in the water-added room-temperature asphalt mixture and the composition of the water-added room-temperature asphalt mixture generally change over time.

  The amount of water added to 100 parts by mass of the normal temperature asphalt mixture is, for example, 20 to 30 parts by mass, and may be due to intentional addition of water or not due to intentional addition of water. May be.

(Action of water-added room temperature asphalt mixture)
The water-added room temperature asphalt mixture according to the present embodiment thickens quickly and to a high viscosity after the contact between the room temperature asphalt mixture and water. Since this thickening action has been explained in the section “Action of normal temperature asphalt mixture”, the explanation is omitted.

(Effect of water-added room temperature asphalt mixture)
The water-added room temperature asphalt mixture according to the present embodiment thickens rapidly and to a high viscosity. For this reason, according to the water addition room temperature asphalt mixture which concerns on this embodiment, even if the road surface is wet, the water addition room temperature asphalt mixture with high adhesiveness and high Marshall stability is obtained. Moreover, according to the water addition normal temperature asphalt mixture which concerns on this embodiment, a normal temperature asphalt mixture pavement with high viscosity and high durability can be formed in a short time regardless of the presence or absence of the road surface. For this reason, according to the water addition normal temperature asphalt mixture which concerns on this embodiment, the traffic in a normal temperature asphalt mixture pavement can be released early regardless of the presence or absence of the road surface.

  The room temperature asphalt mixture according to the present embodiment is manufactured, for example, by the following method.

[Method for producing room temperature asphalt mixture]
The manufacturing method of the normal temperature asphalt mixture which concerns on this embodiment is a manufacturing method which manufactures the normal temperature asphalt mixture which concerns on the said this embodiment, and includes a 1st mixing process, a 2nd mixing process, and a 3rd mixing process. .

(First mixing step)
A 1st mixing process is a process of mixing an aggregate of 100-120 degreeC, and 150-180 degreeC asphalt, and obtaining a 1st mixture. It is preferable to set the aggregate within the above temperature range because the aggregate moisture content decreases and the aggregate can be dried. It is preferable to set the asphalt within the above temperature range because the mixing property with the aggregate is improved. The first mixture includes aggregate and asphalt.

(Second mixing step)
The second mixing step is a step of obtaining the second mixture by mixing the first mixture and a surfactant containing oleic acid. It is preferable for the first mixture to be 90 to 100 ° C. because the mixing with the surfactant is improved. The second mixture includes aggregate, asphalt, and a surfactant containing oleic acid.

  In the normal temperature asphalt mixture obtained, the surfactant contains 60.0 to 66.5% by mass, preferably 61.5 to 66.5% by mass of oleic acid in 100% by mass of the surfactant. When the content of oleic acid in the surfactant is within the above range, a water-added room temperature asphalt mixture having high Marshall stability and dynamic stability is obtained, and a high degree of compaction is obtained even at a low temperature, which is preferable. .

(Third mixing step)
The third mixing step is a step of obtaining the third mixture by mixing the second mixture and the alkaline additive. When the third mixture is heated to 90 to 100 ° C., the mixing property with the alkaline additive is improved, which is preferable. The third mixture includes aggregate, asphalt, a surfactant containing oleic acid, and an alkaline additive. That is, the third mixture is the same as the normal temperature asphalt mixture.

  The normal temperature asphalt mixture obtained has an alkaline additive / surfactant mass ratio of 20 to 100% by mass, preferably 30 to 100% by mass, obtained by dividing the mass of the alkaline additive by the mass of the surfactant. More preferably, it is 50-75 mass%. When the alkaline additive / surfactant mass ratio is within the above range, a water-added room-temperature asphalt mixture having high Marshall stability and dynamic stability is preferable.

  In the obtained room temperature asphalt mixture, the alkaline additive is usually 0.3 to 2.0 parts by mass, preferably 0.4, in addition to 100 parts by mass of the mixture before addition consisting of aggregate, asphalt and surfactant. -1.5 mass part is mix | blended. When the blending amount of the alkaline additive is within the above range, a water-added room-temperature asphalt mixture having a high Marshall stability and a high dynamic anchorage is preferable.

  The manufacturing method of the normal temperature asphalt mixture which concerns on this embodiment may provide a curing process after the said 3rd mixing process.

(Curing process)
The curing step is a step of curing (preserving) the bag in the bag at room temperature after packing the third mixture. Here, the curing in the bag means storing the third mixture in the bag. Since the 3rd mixture is the normal temperature asphalt mixture which concerns on this embodiment, a curing process is a process of curing (preserving) the normal temperature asphalt mixture which concerns on this embodiment in a bag at normal temperature. The curing time for the in-bag curing is usually about 3 months.

(Effect of manufacturing method of normal temperature asphalt mixture)
According to the method for producing a room temperature asphalt mixture according to this embodiment, the room temperature asphalt mixture according to this embodiment can be efficiently produced.

  EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, this invention is not limited to these Examples.

In the following examples, the following materials were used.
(aggregate)
<Coarse aggregate>
・ Crushed stone No. 7 (particle size: 5-2.5mm)
<Fine aggregate>
・ Coarse sand (particle size 2.5mm or less)
<Filler>
・ Stone powder (particle diameter 0.6mm to 0.075mm)
(asphalt)
・ Straight asphalt 60/80
(Surfactant)
・ Hongzhou Jingyou Chemical Co., Ltd. tallow (Talllow acid, oleic acid content 77.7 mass%)
-Plant fatty acid TFA-125 manufactured by Tsukino Food Industries Ltd. (oleic acid content 54.6% by mass)
(Alkaline additive)
-Ordinary Portland cement (trade name: Taiheiyo Cement) manufactured by Taiheiyo Cement Co., Ltd.

  In Table 1, content (mass%) of components, such as oleic acid, in the said beef tallow and vegetable fatty acid is shown. Table 1 shows that beef tallow and vegetable fatty acids do not contain components other than fatty acids.

[Examples 1 to 3, Comparative Examples 1 and 2]
(Preparation of room temperature asphalt mixture)
<Curing raw materials>
First, each raw material was cured at a predetermined temperature. Specifically, crushed stone No. 7 and coarse sand were cured at 120 ° C, straight asphalt 60/80 was cured at 155 ° C, and stone powder, beef tallow, vegetable fatty acids, and ordinary Portland cement were cured at room temperature (20 ° C). .

<Preparation of aggregate mixture>
Next, the aggregate mixture which has the synthetic particle size distribution shown in Table 3 was prepared by mixing the crushed stone 7, No. 7, coarse sand, and stone powder with the compounding quantity shown in Table 2.

<Mixing of the first mixture>
Next, an aggregate mixture composed of crushed stone No. 7, coarse sand and stone powder and 155 ° C. straight asphalt 60/80 were mixed at a blending amount shown in Table 2 to prepare a first mixture of 90 to 100 ° C. .

<Mixing of second mixture>
Furthermore, room temperature beef tallow and room temperature plant fatty acid were added to the first mixture at 90 to 100 ° C. in the blending amounts shown in Table 2 and mixed to prepare a second mixture.

<Mixing of third mixture>
Further, ordinary Portland cement at room temperature was added to the second mixture in the blending amounts shown in Table 2, and mixed to prepare a third mixture (room temperature asphalt mixture).

<Curing process>
Next, the obtained 3rd mixture (normal temperature asphalt mixture) was packaged and preserve | saved.

(Preparation and evaluation of water-added room temperature asphalt mixture)
<Consolidation degree>
About each of the normal temperature asphalt mixture (sample No. A1-A5) after curing in a bag, the compaction temperature (70 degreeC, 60 degreeC, 40 degreeC, 20 degreeC, 0 degreeC, -10) shown in Table 4 within a thermostat. C.) for 12 hours or more. In Table 4, the degree of compaction is not measured for the samples indicated as “−”.
Next, water at room temperature was added to the room temperature asphalt mixture with the blending amounts shown in Table 2 to prepare a water-added room temperature asphalt mixture. Each water-added room-temperature asphalt mixture was quickly put into a mold (mold) and rolled with a Marshall Ranma to prepare a test piece of a water-added room-temperature asphalt mixture having a diameter of 10.16 cm and a height of 6.35 cm. The rolling force in the marshal runner was double-sided with 50 strokes on each side.
Ten minutes after the addition of water to the room temperature asphalt mixture, the specimen was demolded and cured in the air at room temperature for 24 hours. Thereafter, the specimen was put into water, the mass in water was measured, and after making the surface dry, the surface dry mass was measured. Further, the specimen was cured at 110 ° C. for 12 hours and sufficiently dried, and then the air mass was measured.
As the reference density for calculating the degree of compaction, the density of the heated asphalt mixture (sample No. A9) of Comparative Example 3 described later was used. The results of calculating the degree of compaction of the room temperature asphalt mixture are shown in Table 4. The target value of the compaction degree was set to 96.5% or more.

  From Table 4, Examples 1 to 3 (Sample Nos. A3 to A5) show a degree of compaction in which all of the measured specimens at −10 ° C. to 40 ° C. exceed the target compaction degree (96.5%). , Found to be very good. On the other hand, in Comparative Examples 1 and 2 (Sample Nos. A1 and A2), it was found that all or part of the specimens were below the target compaction degree.

<The compaction temperature at which the compaction degree is 96.5% or more>
Further, in Examples 1 to 3 (Sample Nos. A3 to A5) and Comparative Examples 1 and 2 (Sample Nos. A1 and A2), the tightening degree is equal to or higher than the target compaction degree (96.5%). The setting temperature (° C.) was calculated. The compaction temperature at which the target compaction degree can be obtained is the sample number. For each of A1 to A5, an approximate line indicating the relationship between the compaction temperature (° C.) and the compaction degree (%) is calculated based on the measured compaction degree. The range of the compaction temperature (° C.) that is 96.5%) or higher was calculated.
For example, the calculation method of the compaction temperature which becomes more than the target compaction degree in Example 1 (sample No. A3) is shown below. First, four compaction degrees (99.9%, 98.8%, 96.9%, 97.0) measured at four compaction temperatures (40 ° C, 20 ° C, 0 ° C, -10 ° C). %), An approximate straight line was obtained with the horizontal axis representing the compaction temperature (° C.) and the vertical axis representing the compaction degree (%). Next, the range of the compaction temperature (° C.) that is equal to or higher than the target compaction degree (96.5%) was calculated from this approximate straight line. The results are shown in Table 4.

  From Table 4, in Examples 1 to 3 (Sample Nos. A3 to A5), the compaction temperature (° C.) at which the target compaction degree is 96.5 (%) or more is −10 ° C. or more, and the construction is performed at a low temperature. Was found to be very easy. On the other hand, in Comparative Examples 1 and 2 (Sample Nos. A1 and A2), the compaction temperature (° C.) at which the target compaction degree is 96.5 (%) or higher is 95 ° C. or higher or 34 ° C. or higher. It turned out that construction was difficult.

<60 ° C Marshall stability>
About each of the normal temperature asphalt mixture (sample No. A1-A5) after curing in a bag, the compaction temperature (70 degreeC, 60 degreeC, 40 degreeC, 20 degreeC, 0 degreeC, -10) shown in Table 4 within a thermostat. C.) for 12 hours or more. In Table 4, the sample indicated as “−” does not measure the 60 ° C. Marshall stability.
Next, water at room temperature was added to the room temperature asphalt mixture with the blending amounts shown in Table 2 to prepare a water-added room temperature asphalt mixture. Each water-added room-temperature asphalt mixture was quickly put into a mold and rolled with a Marshall Ranma to prepare a specimen of a water-added room-temperature asphalt mixture having a diameter of 10.16 cm and a height of 6.35 cm. The rolling force in the marshal runner was double-sided with 50 strokes on each side.
Ten minutes after the addition of water to the room temperature asphalt mixture, the specimen was demolded and cured in a constant temperature bath at 20 ° C. for 7 days. About the obtained specimen, the Marshall stability test was performed at 60 degreeC, and 60 degreeC Marshall stability (kN) was measured. The results are shown in Table 4.
The target stability of 60 ° C. Marshall stability (kN) was set to 60 ° C. Marshall stability 4.8 kN obtained with the heated asphalt mixture (sample No. A9) of Comparative Example 3 described later.

  From Table 4, Examples 2 and 3 (Sample Nos. A4 and A5) show 60 ° C. Marshall stability in which all of the measured specimens of −10 ° C. to 40 ° C. exceed the target stability (4.8 kN). , Found to be very good. Moreover, Example 1 (sample No. A3) showed 60 degreeC Marshall stability in which the measured specimen of 20 to 40 degreeC measured exceeded target stability, and it turned out that it is comparatively favorable. On the other hand, in Comparative Examples 1 and 2 (Sample Nos. A1 and A2), it was found that all or part of the specimens were below the target stability.

<The compaction temperature at which the 60 ° C Marshall stability is 4.8 kN or higher>
Further, in Examples 1 to 3 (Sample Nos. A3 to A5) and Comparative Examples 1 and 2 (Sample Nos. A1 and A2), the tightening at which the 60 ° C. Marshall stability becomes the target stability (4.8 kN) or more. The setting temperature (° C.) was calculated. The compaction temperature at which the target stability is exceeded is the sample no. For each of A1 to A5, based on the measured 60 ° C. Marshall stability, an approximate straight line showing the relationship between the compaction temperature (° C.) and 60 ° C. Marshall stability (kN) is calculated. The range of compaction temperature (° C.) at which the stability (4.8 kN) or higher was calculated.
For example, a calculation method of a compaction temperature that is equal to or higher than the target stability in Example 2 (Sample No. A4) is shown below. First, four 60 ° C. Marshall stability (8.4 kN, 7.4 kN, 6.2 kN, 5.1 kN) measured at 4 compaction temperatures (40 ° C., 20 ° C., 0 ° C., −10 ° C.) Based on the measured values, an approximate straight line was obtained with the horizontal axis being compacted temperature (° C.) and the vertical axis being 60 ° C. Marshall stability (kN). Next, the range of compaction temperature (° C.) that is equal to or higher than the target stability (4.8 kN) was calculated from this approximate line. The results are shown in Table 4.

  From Table 4, Examples 2 and 3 (Sample Nos. A4 and A5) have a compaction temperature (° C.) of -10 ° C. or higher, which is higher than the target stability (4.8 kN), and the construction at low temperature is very It turned out to be easy. In Example 1 (Sample No. A3), the compaction temperature (° C.) at which the target stability (4.8 kN) or higher was 20 ° C. or higher was found to be relatively easy to construct at a low temperature. On the other hand, Comparative Examples 1 and 2 (Sample Nos. A1 and A2) did not have a compaction temperature (° C.) exceeding the target stability (4.8 kN), and it was found that construction at a low temperature was difficult.

(Evaluation of results shown in Table 4)
Based on the results shown in Table 4, the compaction temperature at which the compaction degree is 96.5% or higher, the 60 ° C Marshall stability, and the compaction temperature at which the 60 ° C Marshall stability is 4.8 kN or higher, In order to make the asphalt mixture a compaction degree of 96.5% or more and a 60 ° C. Marshall stability of 4.8 kN or more, it was found that the mixing ratio of beef tallow in the surfactant is preferably 30% by mass or more. . In addition, as shown in Table 2, “the mixing ratio of beef tallow in the surfactant is 30% by mass or more” corresponds to “the content ratio of oleic acid in the surfactant is 61.5% by mass or more”. .

[Examples 4 to 6, Comparative Examples 3 and 4]
(Preparation of room temperature asphalt mixture)
The normal temperature asphalt mixtures (Sample Nos. A6 to A8) of Examples 4 to 6 were prepared as follows. Specifically, after preparing the 3rd mixture (room temperature asphalt mixture) like Example 1 except having changed the compounding quantity of a raw material as shown in Table 2, this room temperature asphalt mixture was bagged. This prepared the normal temperature asphalt mixture (sample No. A6-A8) of Examples 4-6. Examples 4 to 6 (Sample Nos. A6 to A8) are examples in which the effect of changing the blending amount of ordinary Portland cement is observed.
As Comparative Example 3, a heated asphalt mixture (sample No. A9) having the composition shown in Table 2 was prepared. Furthermore, as Comparative Example 4, a general room temperature asphalt mixture (manufactured by Maeda Road, mild patch (5 mm type), sample No. A10) was prepared.

(Preparation and evaluation of water-added room temperature asphalt mixture)
<Strength development (20 ° C. Marshall stability)>
About Examples 4-6 (sample No. A6-A8), the water addition normal temperature asphalt mixture was prepared as follows, and strength expression (20 degreeC marshall stability) was evaluated.
First, each of the room temperature asphalt mixture (sample No. A6 to A8) after curing in the bag was cured for 12 hours or more at a compaction temperature of 20 ° C. in a thermostatic bath.
Next, water at room temperature was added to the room temperature asphalt mixture with the blending amounts shown in Table 2 to prepare a water-added room temperature asphalt mixture. Each water-added room-temperature asphalt mixture was quickly put into a mold and rolled with a Marshall Ranma to prepare a specimen of a water-added room-temperature asphalt mixture having a diameter of 10.16 cm and a height of 6.35 cm. The rolling force in the marshal runner was double-sided with 50 strokes on each side.
Ten minutes after the addition of water to the room temperature asphalt mixture, the specimen was demolded and cured in a constant temperature bath at 20 ° C. for the curing time shown in Table 5. The obtained specimen was subjected to a Marshall stability test at 20 ° C., and the 20 ° C. Marshall stability (kN) was measured. The results are shown in Table 5.

  From the results of 20 ° C. Marshall stability of Examples 4 to 6 (Sample Nos. A6 to A8) shown in Table 5, the longer the elapsed time after water addition, the greater the 20 ° C. Marshall stability (kN) may be. I understood. Moreover, when the elapsed time after water addition was the same, it turned out that 20 degreeC marshall stability (kN) becomes large, so that the compounding quantity of normal Portland cement increases. Moreover, it turns out that Example 5 and 6 (sample No. A7 and A8) have a 20 degreeC marshall stability (kN) larger than the comparative example 4 (sample No. A10) which is a common normal temperature asphalt mixture. It was.

<Final strength (60 ° C Marshall stability)>
About Examples 4-6 (sample No. A6-A8), the water addition normal temperature asphalt mixture was prepared as follows, and final intensity | strength (60 degreeC marshall stability) was evaluated.
First, each of the room temperature asphalt mixture (sample No. A6 to A8) after curing in the bag was cured for 12 hours or more at a compaction temperature of 20 ° C. in a thermostatic bath.
Next, water at room temperature was added to the room temperature asphalt mixture with the blending amounts shown in Table 2 to prepare a water-added room temperature asphalt mixture. Each water-added room-temperature asphalt mixture was quickly put into a mold and rolled with a Marshall Ranma to prepare a specimen of a water-added room-temperature asphalt mixture having a diameter of 10.16 cm and a height of 6.35 cm. The rolling force in the marshal runner was double-sided with 50 strokes on each side.
Ten minutes after the addition of water to the room temperature asphalt mixture, the specimen was demolded and cured in a constant temperature bath at 20 ° C. for 7 days. About the obtained specimen, the Marshall stability test was performed at 60 degreeC, and 60 degreeC Marshall stability (kN) was measured. The results are shown in Table 5.

For Comparative Example 3 (Sample No. A9), the final strength (60 ° C. Marshall stability) was evaluated. Specifically, in the blending amount shown in Table 2, crushed stone No. 7 heated to 155 ° C., an aggregate mixture consisting of coarse sand and stone powder, and mixed with only 155 ° C. straight asphalt 60/80 and heated to 155 ° C. An asphalt mixture was made.
The heated asphalt mixture was quickly put into a mold and rolled with a Marshall Ranma to prepare a test piece of a heated asphalt mixture having a diameter of 10.16 cm and a height of 6.35 cm. The rolling force in the marshal runner was double-sided with 50 strokes on each side.
The heated asphalt mixture was rolled and the specimen was demolded after air curing for 12 hours or more. About the obtained specimen, the Marshall stability test was performed at 60 degreeC, and 60 degreeC Marshall stability (kN) was measured. The results are shown in Table 5.

  From the results of 60 ° C. Marshall stability of Examples 4 to 6 (Sample Nos. A6 to A8) and Comparative Examples 3 and 4 (Sample Nos. A9 and A10) shown in Table 5, Examples 5 and 6 (Sample No. A7 and A8) were found to have a higher 60 ° C. Marshall stability (kN) than Comparative Example 3 which was the same kind of heated asphalt mixture and Comparative Example 4 which was a general ordinary temperature asphalt mixture.

<Flow resistance (60 ° C wheel tracking (WT) test)>
About Example 5 (sample No. A7), the water addition normal temperature asphalt mixture was prepared as follows, and flow resistance (60 degreeC wheel tracking (WT) test) was evaluated.
First, the room temperature asphalt mixture (sample No. A7) after curing in the bag was cured at a compaction temperature of 20 ° C. for 12 hours or more in a thermostatic bath.
Next, water at room temperature was added to the room temperature asphalt mixture with the blending amounts shown in Table 2 to prepare a water-added room temperature asphalt mixture. A water-added room-temperature asphalt mixture of 30 cm in length, 30 cm in width, and 5 cm in thickness is obtained by quickly putting the water-added room-temperature asphalt mixture into a mold for producing a specimen for wheel tracking (WT) test and rolling 25 times with a roller compactor. A specimen of the mixture was prepared.
After 12 hours from the addition of water to the room temperature asphalt mixture, the specimen was demolded and cured for 7 days in a constant temperature bath at 20 ° C. The obtained specimen was subjected to a wheel tracking (WT) test at 60 ° C., and DS (dynamic stability) (times / mm) was measured. The results are shown in Table 5.

About Comparative example 3 (sample No. A9), flow resistance (60 degreeC wheel tracking (WT) test) was evaluated. Specifically, the crushed stone No. 7 heated to 155 ° C., an aggregate mixture composed of coarse sand and stone powder, and only 155 ° C. straight asphalt 60/80 were mixed to prepare a 155 ° C. heated asphalt mixture.
The heated asphalt mixture is quickly put into a mold for preparing a specimen for wheel tracking (WT) test, and is rolled back and forth 25 times by a roller compactor, so that a sample of a heated asphalt mixture having a length of 30 cm × width 30 cm × thickness 5 cm is obtained. Was made.
The heated asphalt mixture was rolled and the specimen was demolded after air curing for 12 hours or more. The obtained specimen was subjected to a wheel tracking (WT) test at 60 ° C., and DS (dynamic stability) (times / mm) was measured. The results are shown in Table 5.

  From the results of the 60 ° C. wheel tracking (WT) test of Example 5 (Sample No. A7) and Comparative Example 3 (Sample No. A9) and Comparative Example 4 (Sample No. A10) shown in Table 5, Example 5 ( It was found that Sample No. A7) had much higher fluid resistance than Comparative Example 3 (Sample No. A9) and Comparative Example 4 (Sample No. A10).

(Evaluation of results shown in Table 5)
From the results of 20 ° C. Marshall stability of Examples 4 to 6 (Sample Nos. A6 to A8) shown in Table 5, it is found that the 20 ° C. Marshall stability (kN) increases as the blending amount of ordinary Portland cement increases. It was.
In addition, Examples 5 and 6 (Sample Nos. A7 and A8) had a large 60 ° C. Marshall stability (kN), and Example 5 (Sample No. A7) was found to have significantly higher flow resistance.

  As mentioned above, although this invention was demonstrated by embodiment, this invention is not limited to these, A various deformation | transformation is possible within the range of the summary of this invention.

Claims (9)

Aggregate,
With asphalt,
A surfactant containing at least oleic acid;
An alkaline additive;
Including
The room temperature asphalt mixture, wherein the oleic acid is contained in 60.0 to 66.5% by mass in 100% by mass of the surfactant.   2. The room temperature asphalt according to claim 1, wherein an alkaline additive / surfactant mass ratio obtained by dividing the mass of the alkaline additive by the mass of the surfactant is 20 to 100 mass%. blend.   The normal temperature asphalt mixture according to claim 1 or 2, wherein the surfactant contains beef tallow, and the beef tallow is contained in 25 to 60% by mass in 100% by mass of the surfactant.   The alkaline additive is blended in an amount of 0.4 to 1.5 parts by mass in addition to 100 parts by mass of the pre-alkali mixture comprising the aggregate, the asphalt, and the surfactant. The normal temperature asphalt mixture of any one of -3.   5. The room temperature asphalt mixture according to claim 4, wherein the binder mixture composed of the asphalt and the surfactant is contained in an amount of 3.5 to 8.0% by mass in 100% by mass of the mixture before the alkali addition.   A water-added room temperature asphalt mixture comprising the room temperature asphalt mixture according to any one of claims 1 to 5 and water. It is a manufacturing method which manufactures the normal temperature asphalt mixture in any one of Claims 1-5,
A first mixing step in which an aggregate of 100 to 120 ° C. and asphalt of 150 to 180 ° C. are mixed to obtain a first mixture;
A second mixing step of mixing the first mixture and a surfactant containing oleic acid to obtain a second mixture;
A third mixing step of mixing the second mixture and an alkaline additive to obtain a third mixture;
Including
The obtained room temperature asphalt mixture is a method for producing a room temperature asphalt mixture, wherein the oleic acid is contained in an amount of 60.0 to 66.5% by mass in 100% by mass of the surfactant.   The obtained normal temperature asphalt mixture has an alkaline additive / surfactant mass ratio of 20 to 100% by mass obtained by dividing the mass of the alkaline additive by the mass of the surfactant. Item 8. A method for producing a room temperature asphalt mixture according to Item 7.   The method for producing a normal temperature asphalt mixture according to claim 7 or 8, further comprising a curing step of curing the third mixture in a bag at normal temperature after bagging.