Artificial Stone Manufacturing Method and Construction Method

Abstract

To provide a production method and a construction method of artificial stone, eliminating steps of installation, curing, demolding and crushing, and eliminating the need for a temporary storage yard, by reducing conventional steps to improve workability.SOLUTION: The method of producing artificial stone, comprises mixing step S03 of mixing mud, steel slag and a binder according to a prescribed blend ratio, feeding step S10 of feeding the whole mixed material before solidification at once or feeding the mixed material before solidification in divided portions onto an underwater position where artificial stone is used, subsequent to confirming that the mixed material prepared by the mixing step is equal to or below the specified slump, and underwater curing step S11 of curing the mixed material fed onto the underwater position where the artificial stone is used, until the mixed material shows specified strength.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for manufacturing artificial stone and a construction method using earth, steelmaking slag, and a binder.

Background Art

[0002] From the perspective of effective utilization of dredged soil, technologies for producing artificial stone (dredged soil solidified body) by mixing dredged soil and a solidifying material have been developed (see, for example, Patent Documents 1 to 6, Non-Patent Documents 1 and 2). Non-Patent Document 3 discloses the development of a cage mat artificial stone in which a calcia artificial stone obtained by adding a solidifying material to calcia modified soil, which is a technology for effective utilization of dredged soil sand, is filled in a cage mat to form a block shape.

[0003] A general manufacturing process of conventional artificial stone will be described with reference to FIG. 4. A mixing test of earth composed of dredged soil or earth and sand and a binder such as cement is performed in advance (S51), and the mixture is determined (S52). The earth and cement or the like are mixed with this mixture (S53), and this mixed material is placed in a formwork (S54). After curing for a predetermined curing period (at the day level) (S55), it is demolded (S56) and crushed into a predetermined size (S57). After curing the artificial stone of a predetermined size for a predetermined curing period (at the day level) (S58), it is transported to the place of use of the artificial stone (S59) and put into water (S60). Thereby, underwater structures such as fishing reefs, algal reefs, submerged breakwaters, and underwater mounds are constructed.

[0004] Also, the target strength is confirmed in FIG. 4. A sample is taken in the material mixing step S53, and a specimen for a compression strength test is prepared (S61). After curing for, for example, 28 days (S62), a compression strength test is performed (S63). If the compression strength test result exceeds the target strength (YES in step S64), the transportation step S59 is executed. If it is less than the target strength (NO in step S64), the process returns to the mixing step (S53) by re-blending or returns to the curing step (S62) to extend the curing period and perform the compression strength test again.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] JP 2011-93750 A [Patent Document 2] JP 2012-148948 A [Patent Document 3] JP 2012-12287 A [Patent Document 4] JP 2017-122203 A [Patent Document 5] JP 2018-172245 A [Patent Document 6] JP 2018-126673 A [Non-patent literature]

[0006] [Non-Patent Document 1] Yasuo Deji, Taho Tanishiki, Hideki Honda, and Katsunori Takahashi, "Manufacturing Technology of Artificial Stone Using Dredged Soil," 66th Annual Conference of the Japan Society of Civil Engineers, 2011. http: / / library.jsce.or.jp / jsce / open / 00035 / 2011 / 66-05 / 66-05-0594.pdf [Non-Patent Document 2] Tsuji, T.; Tanaka, Y.; Nakagawa, M.; Nonaka, S.; Nagao, K.; Akashi, Y.; Kiso, H.; and Tasaki, C. "Material properties and manufacturing technology of artificial stone made from dredged soil." Journal of Japan Society of Civil Engineers, Vol. 71, No. 2, pp. I_1173-I_1178, 2015. https: / / www.jstage.jst.go.jp / article / jscejoe / 71 / 2 / 71_I_1173 / _article / -char / ja / [Non-Patent Document 3] Yuzo Akashi, Hideyuki Asada, Hirofumi Fukawa, Mitsuo Takikawa, Yuichi Torishima, Hiroyuki Kawashita, and Takeshi Katsumi, "Development of artificial stone basket mats using dredged soil," Journal of Japan Society of Civil Engineers, Vol. 76, No. 2, pp. I_612-I_617, 2020. https: / / www.jstage.jst.go.jp / article / jscejoe / 76 / 2 / 76_I_612 / _article / -char / ja / Summary of the Invention

Problems to be Solved by the Invention

[0007] However, the conventional method for manufacturing artificial stones requires a plurality of steps such as material mixing, casting into a mold, curing, demolding, and crushing as shown in FIG. 4. Therefore, the work is complicated and leads to an increase in manufacturing costs.

[0008] Also, artificial stones usually undergo a strength test after 28 days of curing, and construction such as underwater placement is carried out after confirming the development of a predetermined strength. For this reason, when manufacturing a large amount of artificial stones, a large manufacturing yard and a temporary storage yard are required, and the yard is occupied during the manufacturing period. Also, there is a method of developing strength in the early stage of curing after casting, crushing the solidified body containing soil early, stacking it in a temporary storage yard, and curing it (Patent Document 4), but the effect of shortening the yard occupancy period is limited. Also, there is a method of omitting casting into the mold (Patent Document 6), but the need for a temporary storage yard and a curing period is the same.

[0009] In order to use artificial stones under high wave conditions, for example, it is necessary to produce large artificial stones of about 10 tons or more. As described in Non-Patent Document 3, cage mat artificial stones have been proposed, but it is not necessarily an efficient method. In the conventional manufacturing method, the slump in the slump test (JIS A 1101) is often targeted at 5 to 10 cm in consideration of the workability during casting of the mixed material into the mold.

[0010] In view of the problems of the prior art as described above, the present invention aims to provide a method for manufacturing and constructing artificial stones that reduces the conventional steps to improve workability and does not require the steps of casting, curing, demolding, crushing, and a temporary storage yard.

Means for Solving the Problems

[0011] A method for manufacturing artificial stones for achieving the above object is a method for manufacturing artificial stones by mixing soil, steelmaking slag, and a binder, A mixing step of mixing the soil, the steelmaking slag, and the binder at a predetermined mixing ratio, and confirming that the mixed material by the mixing has a slump of a predetermined value or less Slump confirmation step and , a charging step of integrally or separately charging the mixed material before consolidation to the underwater use position of the artificial stone, and an underwater curing step of curing the mixed material in water until the mixed material charged to the underwater use position exhibits a predetermined strength Furthermore, a specimen preparation step of preparing a specimen from a sample taken from the mixed material after the mixing, a specimen curing step of curing the specimen in the air or in water at a temperature set based on the water temperature at the time of input of the input water area in the input step, and a strength confirmation step of confirming the expression of the predetermined strength in the underwater curing step based on the compressive strength obtained by the compressive strength test of the specimen after a lapse of a certain period, are included .

[0012] According to this method for manufacturing an artificial stone, by integrally or separately charging the mixed material before consolidation that has been reduced to a value equal to or less than the upper limit value of a predetermined slump directly to the underwater use position of the artificial stone, each step of placing, curing, demolding, and crushing in a mold after mixing becomes unnecessary. Therefore, a plurality of conventional steps can be reduced and workability can be improved. Further, by transporting and charging the artificial stone to the construction site where it is used immediately after mixing, each step of placing, curing, demolding, and crushing and the temporary storage yard that were conventionally required become unnecessary, and the manufacturing cost of the artificial stone can be reduced. In addition, since the curing of the specimen is performed at a temperature set based on the water temperature at the time of input of the input water area when confirming the strength expression by the specimen, the influence of the curing temperature can be confirmed .

[0013] In the above method for manufacturing an artificial stone, it is preferable that the slump is a predetermined value within the range of 0 to 7 cm. Thereby, the fluidity of the mixed material can be lowered, the shape of the mixed material after charging can be maintained, and the generation of turbidity during underwater charging can be suppressed.

[0014] It is preferable to measure the slump of the mixed material during mixing and / or before charging.

[0015] It is preferable to previously obtain the relationship between the elapsed time after mixing and the slump for the mixed material In the slump confirmation step, the slump at the time of input is estimated based on the elapsed time after the mixing . Thereby, the slump after a predetermined period has elapsed since the mixing of the mixed material can be estimated, and the slump measurement can be omitted.

[0016] The binder is preferably any one or two, or all of cement, fly ash, and blast furnace slag fine powder.

[0017] The construction method of artificial stone for achieving the above object is a method of constructing artificial stone formed by mixing soil, steelmaking slag, and binder at the underwater use position, the mixing step in the above-described manufacturing method of artificial stone, The slump confirmation step and the charging step, and the underwater curing step, The specimen preparation step, the specimen curing step, and the strength confirmation step are included.

[0018] According to this construction method of artificial stone, by directly charging the mixed material before consolidation, which has decreased to below the upper limit value of a predetermined slump, integrally or dividedly, to the underwater use position of the artificial stone, each process of placing, curing, demolding, and crushing into the mold after mixing becomes unnecessary. Therefore, a plurality of conventional processes can be reduced and workability can be improved. Further, by transporting and charging the artificial stone to the construction site where it is used immediately after mixing, each process of placing, curing, demolding, and crushing and the yard for temporary storage, which were necessary in the past, become unnecessary, and the construction cost of the artificial stone can be reduced.

[0019] In the above construction method of artificial stone, the charging step can be performed using a grab, a bucket of an excavator, or a tremie pipe.

[0020] By adjusting the blending materials and / or blending ratios in the mixing step, the time for the mixed material to decrease to the slump can be adjusted.

[0021] By adjusting the time for the mixed material to decrease to the slump, the transportation time of the mixed material can be ensured between after mixing and before charging. For example, when the mixed material mixed on land or water is loaded onto an earth hauler and transported to the charging position, by adjusting the time for the mixed material to decrease to 7 cm, which is the upper limit value of the predetermined slump, based on such transportation time, the charging of the mixed material can be performed efficiently.

[0022] Also, by adjusting the time it takes for the mixed material to drop to the slump, the time from after mixing to the input can be shortened. For example, when mixing the soil, the steelmaking slag, and the binder on a barge near the input position, transportation of the mixed material is unnecessary, and the mixed material after mixing can be input into the water within a relatively short time. Therefore, the time until input can be significantly shortened, and the input efficiency can be further improved.

[0023] It is preferable to conduct an underwater input experiment on the mixed material and confirm in advance the situation of maintaining the shape of the mass of the mixed material in water and the curing time required for maintaining the shape.

[0024] After the input, by deforming the shape of the mixed material before solidification by pressing or leveling, etc., the shape of the artificial stone can be adjusted and the finish can be managed.

Advantages of the Invention

[0025] According to the present invention, it is possible to provide a method for manufacturing and constructing artificial stones that reduces conventional processes, improves workability, and does not require each process of placing, curing, demolding, crushing, and a yard for temporary storage.

Brief Description of the Drawings

[0026]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0027] Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. Figure 1 is a flowchart for explaining manufacturing steps S01 to S15 of artificial stone according to this embodiment.

[0028] The method for manufacturing artificial stone according to this embodiment will be described with reference to Figure 1. First, by conducting a blending test of dredged soil (cohesive soil · sandy soil), mud composed of earth and sand, a binder such as steelmaking slag and cement, the elapsed time after mixing, the slump, and the developed strength after casting and curing are confirmed (S01), and the blending materials and blending ratios are determined (S02). For mud with significantly different water contents, separate blending tests are conducted as different blending materials.

[0029] Next, the dredged soil or mud composed of earth and sand, the steelmaking slag, and the binder such as cement are mixed at the determined blending materials and blending ratios (S03). Such mixing can be performed by a mixer, a backhoe, drop mixing, or the like.

[0030] As the binder, any one, two, or all of cement, fly ash, and fine powder of blast furnace slag can be used. As the fine powder of blast furnace slag, those obtained by pulverizing granulated blast furnace slag or those with gypsum added thereto can be used.

[0031] In addition, in this specification, the material before consolidation obtained by mixing mud, steelmaking slag, and a binder is referred to as a mixed material, and the material that has developed a predetermined strength after consolidation is referred to as artificial stone.

[0032] Next, for the mixed material obtained by mixing the soil, steelmaking slag, and binder in the mixing step S03, the slump during underwater injection in the subsequent process (loading step S07) is estimated (S04). Since the slump of the mixed material decreases with the passage of time after mixing, the slump is estimated based on the time required for loading and transporting the mixed material from after mixing to before injection. It is preferable to obtain in advance the relationship between the elapsed time after mixing and the slump, such as shown in FIG. 3 described later, for such slump estimation.

[0033] Also, when the slump of the mixed material before solidification falls within a predetermined value, for example, 5 cm or less, underwater injection is performed. At this time, it is necessary that the mixed material is before solidification.

[0034] As a result of the slump estimation S04, when the slump does not become 5 cm or less even considering the time required for loading and transporting (NO in step S04), the mixed material is cured for a curing period at the time level (S05), and after curing for a certain time, the measurement is performed again.

[0035] As a result of the slump estimation S04, when the slump becomes 5 cm or less considering the time required for loading and transporting and the curing time in the curing step S05 (YES in step S04), the mixed material is transported to the underwater injection position by a soil hauler or the like (S06).

[0036] When the soil hauler or the like carrying the mixed material arrives at the underwater injection position, the slump of the mixed material is measured (S07). If the measurement result does not become 5 cm or less (NO in step S08), the mixed material is cured for a curing period at the time level by a soil hauler or the like (S09).

[0037] When the slump measurement result of the mixed material is 5 cm or less (including the case considering the curing time in the curing step S09) (YES in step S08), since it is confirmed that the slump is 5 cm or less, the mixed material is divided into a predetermined size and put into the underwater use position of the artificial stone (S10). Such divided input can be performed using a grab or the bucket of an excavator. In this way, the mixed material can be transported before solidification, divided into an arbitrary size without using a formwork, and put into the water. Also, even if the mixed material is collectively put into the water by a bottom-opening barge, it may be divided into relatively large chunks (for example, 10 tons or more) and put in.

[0038] Note that before solidification of the mixed material means the stage before solidification progresses and it becomes impossible to input by a grab, the bucket of an excavator, etc. The mixed material at this stage does not exhibit the compressive strength required for the artificial stone. Therefore, scooping up the mixed material by a grab, a bucket, etc. and dividing it into a predetermined size when putting it into the water is different from crushing the artificial stone after solidification.

[0039] The mixed material put into the underwater use position as described above is cured in the water (S11) to obtain an artificial stone of a predetermined strength.

[0040] Also, as shown in FIG. 1, for manufacturing construction management, a sample is taken from the mixed material before input to prepare a specimen (S12), cured for a certain period (usually 28 days) (S13), a compressive strength test is performed (S14), and it is confirmed that the compressive strength exceeding the target strength is exhibited (S15). Note that when the target strength is not reached (NO in step S15), the curing time in the specimen curing step S13 is extended. Also, when the target strength is reached (YES in step S15), the strength exhibited after underwater input can be estimated.

[0041] According to the method for manufacturing artificial stone of FIG. 1, the mixed material before consolidation, which has decreased to below the upper limit value of a predetermined slump, is made into a predetermined size integrally or dividedly and directly put into the underwater use position of the artificial stone. Therefore, each process of placing, curing, demolding, and crushing the mixed material in a mold is unnecessary. For this reason, a plurality of conventional processes can be reduced and workability can be improved. In addition, since the mixed material can be made to decrease to a predetermined slump during the transportation time of the mixed material before charging after mixing, each process of placing, curing, demolding, and crushing and the yard for temporary storage, which were necessary in the past, become unnecessary, and the manufacturing cost of artificial stone can be reduced.

[0042] Also, by setting the slump of the mixed material at the time of underwater charging to, for example, 5 cm or less, the fluidity of the mixed material can be lowered, the shape of the mixed material after charging can be maintained, and the generation of turbidity at the time of underwater charging can be suppressed. Note that 5 cm or less of slump is the target value at the time of charging, and the slump may be larger than this immediately after mixing.

[0043] Next, another example of the method for manufacturing artificial stone according to the present embodiment will be described with reference to the flowchart of FIG. 2. FIG. 2 shows a case where a marine production form is adopted in which a mixed material is produced at sea around the underwater use position of the artificial stone. The pre-mixing test step S21, the mixing ratio determination step S22, and the mixing step S23 in FIG. 2 are performed in the same manner as the steps S01, S02, and S03 in FIG. 1. However, when determining the mixing materials and the mixing ratio, the slump of the mixed material immediately after mixing is set to be 5 cm or an approximate value thereof as the target value.

[0044] Next, the slump of the mixed material is measured (S24). If the measurement result is not 5 cm or less (NO in step S25), the mixed material is cured for a curing period at the time level (S26), and after curing for a certain period of time, the measurement is performed again.

[0045] When the measurement result of the slump becomes 5 cm or less (YES in step S25), the mixed material is made into a predetermined size integrally or dividedly and put into the underwater use position of the artificial stone (S27). The charging method may be the same as the charging step S10 in FIG. 1.

[0046] Cure the mixed material placed at the underwater use position as described above in water (S28) to obtain artificial stone that exhibits a predetermined strength. As shown in FIG. 2, for manufacturing construction management, specimens are prepared and steps S12 to S15 are performed in the same manner as in FIG. 1.

[0047] According to the method for manufacturing artificial stone in FIG. 2, the mixed material before consolidation that has dropped to a predetermined slump is made into a predetermined size integrally or dividedly and directly put into the underwater use position of the artificial stone. Therefore, each process of placing, curing, demolding, and crushing the mixed material into a formwork becomes unnecessary. For this reason, a plurality of conventional processes can be reduced and workability can be improved. Also, by adjusting the blending materials and blending ratios of the mixed material so that the slump immediately after mixing in the mixing step S23 in FIG. 2 becomes, for example, 5 cm or an approximate value of the target value, the mixed material can be put in immediately after mixing. For example, by mixing the mixed material on a barge near the input position, the transportation of the mixed material becomes unnecessary, and the mixed material after mixing can be put into water within a relatively short time. Thereby, the time until the mixed material is put in can be significantly shortened, and the input efficiency can be further improved. Also, each process of placing, curing, demolding, and crushing and the temporary storage yard that were conventionally required become unnecessary, and the manufacturing cost of the artificial stone can be reduced.

[0048] The artificial stone manufactured as shown in FIGS. 1 and 2 can be used for backfill stones such as revetments, fishing reefs, algal reefs, submerged breakwaters, rubble mounds, artificial seamounts, etc. Also, since underwater structures and underwater structures such as backfill structures of revetments, fishing reefs, algal reefs, submerged breakwaters, rubble mounds, covering stones, artificial seamounts, etc. can be constructed by the input of the mixed material, each step in FIGS. 1 and 2 is also a construction step of underwater structures and underwater structures using artificial stone.

[0049] In the above underwater structures and underwater structures, with the artificial stone according to this embodiment, it is possible to form a gradient of about 1:1 to 1:3 in the same manner as normal stone stacking.

[0050] In this embodiment, the mixing ratio of mud (dredged soil) is 40 vol% or more, and a predetermined compressive strength (for example, 9.8 N / mm 2Assuming the above, it is preferable to determine the compounding conditions that result in a slump value equal to or less than a predetermined value that satisfies this condition through prior compounding tests. Also, it is preferable to conduct an underwater casting experiment using a water tank or beaker during the compounding test to confirm the maintenance status of the shape of the mass in water and the curing time required for shape maintenance. Note that depending on the use of the artificial stone, a compressive strength of 9.8 N / mm 2 or higher may not be necessary. In this case, a predetermined compressive strength of less than 9.8 N / mm 2 and equal to or higher than 1.0 N / mm 2 (about the lower limit value of soft stone or soft rock) is targeted.

[0051] Also, since the developed strength of the artificial stone is affected by the curing temperature, it is desirable to confirm the influence of the curing temperature in advance by performing the specimen curing in step S13 of FIG. 1 at the set temperature (0 to 30 °C in air or water) based on the water temperature at the time of casting in the casting water area. Further, it is desirable to adjust the construction time and timing according to the sea state conditions so that the mixed material cast underwater is not affected by high waves before strength development.

[0052] Also, as examples of the casting construction of the mixed material, there are the following three forms, and the steps described in FIG. 1 or FIG. 2 are performed according to the embodiment. (1) Mixing on land → Transportation by an earth transport ship or the like → Underwater casting by a grab, backhoe, bottom-opening version, etc. (2) Offshore mixing by a barge or the like → Transportation by an earth transport ship or the like → Underwater casting by a grab, backhoe, bottom-opening version ship, etc. (3) Offshore mixing by a barge or the like → Underwater casting by a grab, backhoe, etc. Note that there is also a method of pouring into a tremie pipe instead of a grab or a backhoe and placing it underwater from the tip thereof.

[0053] The size of the artificial stone is determined by the size of the grab or bucket used above. Also, by using a large grab or bucket, it is possible to produce a large artificial stone.

[0054] In addition, since the mixed material is not solidified at the time of input, it is possible to adjust the shape of the artificial stone and manage the formed shape by deforming it by pressing or leveling after input. For example, in the case of a shallow site, the shape of the artificial stone input from the barge can be directly formed using a long backhoe. In addition, the adjacent masses that are input adhere to each other and become a larger mass, increasing the stability.

[0055] (Experimental Example) The mixed material was prepared according to the following two mixing examples A and B, and the slump reduction situation over time after mixing was investigated. The slump was measured based on JIS A 1101 2005. In this experiment, the target slump value was set to 5 cm. Mixing Example A: Dredged soil with liquid limit of 84.3% and water content ratio of 150%: 683 kg / m 3 Steelmaking slag: 1154 kg / m 3 Fine powder of blast furnace slag: 410 kg / m 3 Mixing Example B: Dredged soil with liquid limit of 84.3% and water content ratio of 175%: 663 kg / m 3 Steelmaking slag: 1140 kg / m 3 Fine powder of blast furnace slag: 422 kg / m 3

[0056] Fig. 3 shows the relationship between the elapsed time after mixing and the measured slump for each mixed material according to Mixing Examples A and B of this experimental example. It can be seen from Fig. 3 that the slump decreases with the passage of time for both Mixing Examples A and B. Since the slump of Mixing Example A is 5 cm immediately after mixing, it can be input immediately after mixing, corresponding to Fig. 2, Input Construction Example (3). In addition, Mixing Example B requires about 2 hours from mixing until the slump reaches 5 cm, and this time can be used as the time required for loading and transporting the mixed material, corresponding to Fig. 1, Input Construction Examples (1) and (2). The 28-day age compressive strength was tested on specimens in an indoor atmosphere. Mixing Example A: 16.2 N / mm 2 , Mixing Example B: 13.2 N / mm 2 was.

[0057] Also, as a further experimental example, for each of the mixed materials according to the following compounding examples C and D, a water immersion experiment using a beaker was conducted to check the state of maintenance of the shape of the mass in water. Compounding example C: Dredged soil with a liquid limit of 120.6% and a water content ratio of 200%: 648 kg / m 3 Steelmaking slag: 1143 kg / m 3 Blast furnace cement: 362 kg / m 3 Compounding example D: Dredged soil with a liquid limit of 120.6% and a water content ratio of 200%: 648 kg / m 3 Steelmaking slag: 834 kg / m 3 Blast furnace cement: 300 kg / m 3 Fly ash: 280 kg / m 3

[0058] Fig. 5(a) is a photograph showing the state of a lump of about 400 g, corresponding to a diameter of 70 to 80 mm, obtained by dropping the mixed material of Formulation Example C into water immediately after mixing. Fig. 5(b) is a photograph showing the state of the lump obtained by dropping the mixed material of Formulation Example C into water immediately after mixing (left side) and the state of the lump obtained by dropping it into water 3 hours after mixing (right side). As shown in Fig. 5(a) and the left side of Fig. 5(b), in the mixed material C, even when the slump was 5 cm or less, the lump collapsed when dropped into water immediately after mixing. However, as shown in the right side of Fig. 5(b), the shape of the lump was maintained when dropped into water 3 hours after mixing. Therefore, when such a phenomenon is confirmed in the water-drop experiment during the formulation test, it is preferable to set the water-drop timing to about 3 hours after mixing. Also, in the case of Formulation Example D in which fly ash was further appropriately blended into Formulation Example C, the shape of the lump was maintained both when dropped into water immediately after mixing as shown in the left side of Fig. 5(c) and when dropped into water 3 hours after mixing as shown in the right side of Fig. 5(c). Therefore, in such a case, it is possible to drop it either immediately after mixing or 3 hours after mixing. Note that the lump obtained by dropping into water 3 hours after the experiment in this example is also in a state where it deforms when pressed. Since the actual lump weighs several hundred kg to several tons, it is considered that it deforms under its own weight. Also, a gap is formed between the actual lumps, and even if it solidifies as it is, gaps are also formed in the case of dropping ordinary artificial stone into water, so this is not a problem.

[0059] As described above, the embodiments for carrying out the present invention have been explained, but the present invention is not limited to these, and various modifications are possible within the scope of the technical idea of the present invention. For example, in Figs. 1 and 2, a predetermined slump, which is a parameter for determining the input timing of the mixed material, was set to 5 cm. However, the present invention is not limited to this, and it may be set to another value within the range of 0 to 7 cm. If it is within this range, the generation of turbidity after dropping into water can be suppressed.

[0060] Also, in Fig. 1, the slump of the mixed material was measured in the measurement step S07 before input. However, the present invention is not limited to this, and it may be measured between the mixing step S03 and the slump estimation step S04. The slump may be measured both ways, but it may be measured either way.

Industrial Applicability

[0061] According to the manufacturing method and construction method of the artificial stone of the present invention, a curing yard that was conventionally required is unnecessary, placing, curing, demolding, and crushing are unnecessary, and the manufacturing and construction costs can be significantly reduced. Normally, after 28 days of curing and after strength confirmation, it is put into water, whereas it is possible to put it into the sea area immediately after mixing or several hours later. Immediately after putting it into the sea area before solidification, the mixing materials can be easily leveled. Since reinforcement, cage mats, etc. are unnecessary, large artificial stones can be easily manufactured. In addition, when the mixing materials solidify after being put in, it can be expected that the artificial stone will increase in size and stability.

Claims

1. A method for manufacturing artificial stone by mixing soil, steelmaking slag, and a binder, comprising: a mixing step of mixing the soil, the steelmaking slag, and the binder at a predetermined mixing ratio; a slump confirmation step of confirming that the mixed material obtained by the mixing has a slump equal to or less than a predetermined value; a charging step of charging the mixed material before consolidation integrally or dividedly into the underwater use position of the artificial stone; an underwater curing step of curing the mixed material in water until the mixed material charged into the underwater use position exhibits a predetermined strength; further, a specimen preparation step of preparing a specimen from a sample taken from the mixed material after the mixing; a specimen curing step of curing the specimen in air or water at a temperature set based on the water temperature at the time of charging in the charging water area in the charging step; a strength confirmation step of confirming the expression of the predetermined strength in the underwater curing step based on the compressive strength obtained by a compressive strength test of the specimen after a certain period of time has elapsed. A method for manufacturing artificial stone including these steps.

2. The method for manufacturing artificial stone according to claim 1, wherein the slump is a predetermined value within the range of 0 to 7 cm.

3. The method for manufacturing artificial stone according to claim 1 or 2, wherein the slump of the mixed material is measured during the mixing and / or before the charging.

4. The method for manufacturing artificial stone according to any one of claims 1 to 3, wherein the relationship between the elapsed time after mixing and the slump of the mixed material is obtained in advance, and the slump at the time of charging is estimated based on the elapsed time after mixing.

5. The method for manufacturing artificial stone according to any one of claims 1 to 4, wherein the binder is any one or two, or all of cement, fly ash, and blast furnace slag fine powder.

6. A method for constructing artificial stone by mixing soil, steelmaking slag, and a binder at an underwater use position, comprising: the mixing step, the slump confirmation step, the charging step, the underwater curing step, the specimen preparation step, the specimen curing step, and the strength confirmation step in the method for manufacturing artificial stone according to any one of claims 1 to 5. A method for constructing artificial stone including these steps.

7. The method for constructing artificial stone according to claim 6, wherein the charging step is performed using a grab, a bucket of an excavator, or a tremie pipe.

8. The method for constructing artificial stone according to claim 6 or 7, wherein the time for the mixed material to decrease to the slump is adjusted by adjusting the blending materials and / or the blending ratio in the mixing step.

9. The construction method of artificial stone according to claim 8, wherein the transportation time of the mixed material is ensured between after mixing and before charging by adjusting the time for the mixed material to decrease to the slump.

10. The construction method of artificial stone according to claim 8, wherein the time from after mixing to charging is shortened by adjusting the time for the mixed material to decrease to the slump.

11. The construction method of artificial stone according to any one of claims 6 to 10, wherein a water injection experiment is conducted on the mixed material, and the situation of maintaining the shape of the mass of the mixed material in water and the curing time required for maintaining the shape are confirmed in advance.

12. The construction method of artificial stone according to any one of claims 6 to 11, wherein the shape of the artificial stone is adjusted by deforming the shape of the mixed material before consolidation after charging.

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