Fluidity enhancement system for cement composition, and fluidity enhancement method for cement composition

Abstract

To enhance sustainability of fluidity, while efficiently enhancing the fluidity of a cement composition in a short period of time.SOLUTION: A fluidity enhancement system of a cement composition includes: a first storage part for storing a fluidized cement composition having an aggregate; and a second storage part for storing a medium, and has: a container having a length in a predetermined direction; a vibration impartment device for imparting vibration to the cement composition; and an ultrasonic irradiation device for irradiating the cement composition with ultrasonic waves through the medium.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a system for improving the fluidity of a cement composition and a method for improving the fluidity of a cement composition. [Background technology]

[0002] Patent Document 1 discloses a test to confirm that the fluidity of a material, which is any one of fresh concrete, fresh mortar, and fresh cement paste, is improved by irradiating ultrasonic waves through a medium such as water.The test results also show that the material irradiated with ultrasonic waves maintains its flow properties better than the material not irradiated with ultrasonic waves. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-147195 A Summary of the Invention [Problem to be solved by the invention]

[0004] The test disclosed in Patent Document 1 targets a small amount of material (cement paste) of about 1.5 liters. Therefore, even if the output of the ultrasonic irradiation device is small, about 100 to 600 W, and the ultrasonic irradiation time is short, about 3 to 5 minutes, the fluidity of the material can be improved. However, in an actual construction site, the fluidity of a large amount of cement composition must be improved. To achieve this, a very large ultrasonic energy is required, and the ultrasonic irradiation device must be enlarged or ultrasonic irradiation must be performed for a long period of time. Therefore, although the durability of fluidity can be improved by irradiating ultrasonic waves to the cement composition, it has been difficult to actually implement this.

[0005] The present invention has been made in consideration of the above problems, and a main object of the present invention is to improve the fluidity of a cement composition efficiently in a short period of time while increasing the sustainability of the fluidity. [Means for solving the problem]

[0006] In order to achieve this object, the present invention provides A container having a first container portion for containing a fluidized cement composition having aggregate and a second container portion for containing a medium, the container having a length in a predetermined direction; A vibration imparting device that imparts vibration to the cement composition; An ultrasonic irradiation device that irradiates ultrasonic waves to the cement composition through the medium; The fluidity improving system for a cement composition is characterized by comprising: Other features of the present invention will become apparent from the description of this specification. Effect of the Invention

[0007] According to the present invention, it is possible to efficiently improve the fluidity of a cement composition in a short period of time, while increasing the durability of the fluidity. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is an overall perspective view of the fluidity improvement system 1. [Diagram 2] 1 is a schematic cross-sectional view of a portion of a fluidity enhancement system 1. FIG. [Diagram 3] FIG. 2 is a perspective view of the vibration imparting device 20. [Figure 4] FIG. 4A is a schematic cross-sectional view of the test device 40, and FIG. 4B is a schematic top view of the test device 40. As shown in FIG. [Diagram 5] 1 is a graph showing the results of Test 1 in which cement paste was used as a sample. [Figure 6] 1 is a graph showing the results of Test 2 in which mortar was used as a sample. [Figure 7] 1 is a graph showing the results of Test 2 in which mortar was used as a sample. [Figure 8]1 is a graph showing the results of Test 3 in which concrete was used as a sample. [Figure 9] 1 is an explanatory diagram of a modified example of the liquidity improvement system 1. FIG. [Figure 10] 10A and 10B are explanatory diagrams of a modified example of the fluidity improving system 1. FIG. [Figure 11] FIG. 2 is a diagram showing a flow of a method for improving the fluidity of a cement composition 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Preferred embodiments of the present invention will be described in detail below, however, the present invention is not limited to the following embodiments. (Aspect 1) The system for improving the fluidity of a cement composition comprises a container having a length in a predetermined direction, the container comprising a first container section for containing a fluidized cement composition having aggregate and a second container section for containing a medium, a vibration imparting device for imparting vibrations to the cement composition, and an ultrasonic irradiation device for irradiating ultrasonic waves to the cement composition via the medium.

[0010] According to the first aspect, ultrasonic waves can be applied to the cement composition while the vibration applying device breaks up the aggregates of the cement composition. Therefore, compared with the case where only one of the vibration applying device and the ultrasonic irradiation device is operated, the fluidity of the cement composition can be improved efficiently in a short time. In addition, by applying ultrasonic waves to the cement composition, the durability of the fluidity can be increased.

[0011] (Aspect 2) A system for improving the fluidity of a cement composition according to aspect 1, The cement composition flows from one side to the other side of the first container in the specified direction, and the ultrasonic irradiation device is provided continuously or intermittently from a position corresponding to the one side of the first container in the specified direction to a position corresponding to the other side.

[0012] According to the second aspect, ultrasonic waves can be applied to the cement composition during the period in which the cement composition flows and moves in a predetermined direction, thereby improving the fluidity.

[0013] (Aspect 3) A system for improving the fluidity of a cement composition according to aspect 1 or 2, The cement composition flows from one side to the other side of the first container in the predetermined direction, and the vibration imparting device is provided on the one side of the first container in the predetermined direction.

[0014] According to the third aspect, the vibration can be imparted by the vibration imparting device at the stage when the cement composition starts to flow. Therefore, it becomes easier to impart ultrasonic waves to the deflocculated cement composition, and the fluidity of the cement composition can be improved more efficiently.

[0015] (Aspect 4) A system for improving the fluidity of a cement composition according to any one of aspects 1 to 3, The cement composition is provided with a supply device that supplies the cement composition in a fluid state to the first storage section, and a delivery device that receives the cement composition from the first storage section and delivers it to a casting site.

[0016] According to the fourth embodiment, the fluidity of the cement composition can be improved by utilizing the period during which the cement composition moves from the supply device to the delivery device.

[0017] (Aspect 5) A system for improving the fluidity of a cement composition according to aspect 4, The first storage section is inclined downward from the supply device side toward the delivery device side in the predetermined direction.

[0018] According to the fifth embodiment, the cement composition can be caused to flow in a predetermined direction by the gravity of the cement composition.

[0019] (Aspect 6) A system for improving the fluidity of a cement composition according to aspect 4 or 5, The apparatus further includes a conveying mechanism that conveys the cement composition in the first storage unit from the supply device side to the delivery device side in the predetermined direction.

[0020] According to the sixth aspect, the cement composition can be transported in a predetermined direction. The speed at which the cement composition flows in the predetermined direction can be easily adjusted, and the time for which vibration or ultrasonic waves is applied can be easily adjusted.

[0021] (Aspect 7) A system for improving the fluidity of a cement composition according to any one of aspects 1 to 6, The vibration imparting device has a jig that is vibrated by a vibrator and spreads in the surface direction of the cement composition.

[0022] According to the seventh aspect, the vibration of the vibrator can be applied to the cement composition over a wide range in the planar direction via the jig, and therefore the fluidity of the cement composition can be improved more reliably.

[0023] (Aspect 8) A system for improving the fluidity of a cement composition according to any one of aspects 1 to 7, The cooling device includes at least one of a cooling device that cools the medium and a circulating device that circulates the medium.

[0024] According to the eighth aspect, the temperature of the medium can be lowered and the temperature rise of the medium caused by the heat generated during operation of the ultrasonic irradiation device can be suppressed. Therefore, the density of the medium can be increased, and ultrasonic waves can be more efficiently propagated to the cement composition.

[0025] (Aspect 9) A system for improving the fluidity of a cement composition according to any one of aspects 1 to 8, The medium is a degassed liquid.

[0026] According to the ninth aspect, the density of the medium can be increased, and ultrasonic waves can be more efficiently propagated to the cement composition.

[0027] (Aspect 10) The method for improving the fluidity of a cement composition comprises a vibration imparting step of imparting vibration to a cement composition in a fluid state containing aggregate, and an ultrasonic irradiation step of irradiating the cement composition with ultrasonic waves via a medium.

[0028] According to the tenth aspect, ultrasonic waves can be applied to the cement composition while the cement composition is deaggregated by the vibration applying device. Therefore, compared with the case where only one of the vibration applying step and the ultrasonic irradiation step is performed, the fluidity of the cement composition can be improved efficiently in a short time. In addition, by applying ultrasonic waves to the cement composition, the durability of the fluidity can be increased.

[0029] (Aspect 11) A method for improving the fluidity of a cement composition according to aspect 10, comprising: The ultrasonic irradiation step has a period overlapping with the vibration applying step.

[0030] According to the eleventh aspect, the cement composition that has been deaggregated by the vibration applying step can be irradiated with ultrasonic waves, and therefore the fluidity of the cement composition can be improved more efficiently.

[0031] (Aspect 12) A method for improving the fluidity of a cement composition according to aspect 10 or 11, In the ultrasonic irradiation step, the ultrasonic irradiation time is 600 seconds or less.

[0032] According to the twelfth aspect, energy saving can be achieved compared to the case where the ultrasonic irradiation time is longer than 600 seconds. In addition, by not lengthening the irradiation time more than necessary, material separation (sedimentation and coagulation of aggregate) can be suppressed while improving the fluidity of the cement composition.

[0033] (Aspect 13) A method for improving fluidity of a cement composition according to any one of aspects 10 to 12, comprising: In the vibration applying step, the cement composition is subjected to vibration for a period of less than 60 seconds.

[0034] According to the thirteenth aspect, energy saving can be achieved compared to the case where the vibration is applied for 60 seconds or more. In addition, by not extending the vibration application time more than necessary, material separation (sedimentation and coagulation of aggregate) can be suppressed while improving the fluidity of the cement composition.

[0035] <<<Embodiment>>> === Overview of Liquidity Improvement System 1 === Fig. 1 is an overall perspective view of the fluidity improvement system 1. Fig. 2 is a schematic cross-sectional view of a portion of the fluidity improvement system 1. Fig. 3 is a perspective view of a vibration imparting device 20. The fluidity improvement system 1 for a cement composition includes a container 10, a vibration imparting device 20, and an ultrasonic irradiation device 30.

[0036] The container 10 includes a first container section 11 for containing a fluidized cement composition 2 containing aggregate, and a second container section 12 for containing a medium 3. The container 10 extends in a predetermined direction and has a length in the predetermined direction. The first container section 11 illustrated in FIG. 1 is surrounded by a pair of walls and a bottom that face each other in a width direction perpendicular to the predetermined direction, and is open at the top. The second container section 12 is a box-shaped section located below the first container section 11 and capable of sealingly containing the medium 3.

[0037] The term "fluid state" refers to the state before the cement composition hardens. Examples of the cement composition containing aggregate include concrete and mortar.

[0038] Concrete contains cement, water, fine aggregate, coarse aggregate, admixture, and admixture as necessary as constituent materials. In the concrete according to this embodiment, the mass ratio of water to cement (W / C) is preferably 0.1 to 0.65, more preferably 0.35 to 0.55, and even more preferably 0.40 to 0.50. The mass ratio of aggregate (fine aggregate and coarse aggregate) to cement ((S+G) / C) is preferably 0.5 to 4.0, more preferably 0.6 to 3.5, and even more preferably 0.8 to 3.0.

[0039] The mortar contains cement, water, fine aggregate, admixture, and, if necessary, admixture as constituent materials. In the mortar according to this embodiment, the mass ratio of water to cement (W / C) is preferably 0.1 to 0.65, more preferably 0.35 to 0.55, and even more preferably 0.40 to 0.50. The mass ratio of fine aggregate to cement (S / C) is preferably 0.5 to 4.0, more preferably 0.6 to 3.5, and even more preferably 0.8 to 3.0.

[0040] The cement is not particularly limited, and any known and commonly used cement may be used, for example, Portland cement (ordinary Portland cement, high-early-strength Portland cement, ultra-high-early-strength Portland cement, moderate-heat Portland cement, low-heat Portland cement, etc.), mixed cement (cement mixed with blast-furnace cement, silica cement, fly ash cement, etc.), ecocement, special cement (white Portland cement, alumina cement, ultra-high-speed hardening cement, grout cement, oil well cement, etc.), etc. These cements may be used alone or in combination of two or more.

[0041] The aggregate is not particularly limited, and any known and commonly used aggregate may be used, for example, natural aggregate (river sand, river gravel, land sand, mountain sand, sea sand, etc.), artificial aggregate (crushed stone, crushed sand, artificial lightweight aggregate, blast furnace slag aggregate, etc.), recycled aggregate, etc. These aggregates may be used alone or in combination of two or more. The fine aggregate can be one that passes through a 10 mm sieve and 85% or more by mass passes through a 5 mm sieve, while the coarse aggregate can be one that is retained by 85% or more by mass through a 5 mm sieve.

[0042] The admixture is not particularly limited, and any known and commonly used admixture may be used. Examples of the admixture include chemical admixtures such as air entraining agents, water reducing agents, air entraining water reducing agents, high performance air entraining water reducing agents, and superplasticizers.

[0043] The admixture is not particularly limited, and any known and commonly used admixture may be used, for example, ground granulated blast furnace slag, fly ash, silica fume, crushed stone powder such as ground limestone, sludge powder, ground waste concrete, expansive agents, etc.

[0044] The vibration imparting device 20 is a device that imparts vibration to the cement composition 2. As shown in Fig. 3, the vibration imparting device 20 has a jig 22 that is vibrated by a vibrator 21 and spreads in the surface direction of the cement composition 2.

[0045] The vibrator 21 is exemplified by a rod-shaped vibrator that is often used during concrete compaction work, but is not limited thereto. The vibration direction of the vibrator 21 is not particularly limited, and may be vibrated in a horizontal direction or a vertical direction with respect to the surface of the cement composition 2, for example. The number of vibrators 21 is not limited to one, and may be multiple. The jig 22 is a lattice-shaped reinforcing bar, and has multiple reinforcing bars 221 arranged at intervals in a predetermined direction and multiple reinforcing bars 221 arranged at intervals in a width direction perpendicular to the predetermined direction. In addition, a connecting jig 222 for connecting the vibrator 21 to the jig 22 is provided at the center of the jig 22. The tip of the vibrator 21 (rod-shaped vibrator) is inserted and fixed in the connecting jig 222, and is erected against the lattice-shaped surface of the jig 22.

[0046] The ultrasonic irradiation device 30 is disposed inside (at the bottom) of the second storage section 12, and indirectly irradiates ultrasonic waves to the cement composition 2 contained in the first storage section 11 through a medium 3 such as water contained in the second storage section 12. As an ultrasonic irradiation device, a device using a Langevin type transducer (BL transducer) that vibrates ultrasonic vibrations and an ultrasonic oscillator 31 that oscillates ultrasonic waves can be exemplified, but is not particularly limited, and may be a device that oscillates ultrasonic vibrations by another method. The ultrasonic irradiation device 30 is connected to the ultrasonic oscillator 31 by a cable, and the ultrasonic oscillator 31 can control the frequency, amplitude, output, and on / off of the ultrasonic waves.

[0047] ===Test=== Fig. 4A is a schematic cross-sectional view of the test apparatus 40, and Fig. 4B is a schematic top view of the test apparatus 40. The test apparatus 40 was actually produced, and a test was carried out on the fluidity of the cement composition 2 in a fluid state.

[0048] The test device 40 has a container 41, a vibration imparting device 42, and an ultrasonic irradiation device 43, similar to the fluidity improvement system 1 illustrated in FIG. 1. The container 41 is a container that is open at the top and recessed, and the recessed portion is a first container 411 that accommodates the cement composition 2. The side walls and bottom that surround the first container 411 from all sides are hollow, and the hollow space is a second container 412 that accommodates the medium 3. The vibration imparting device 42 has a vibrator 421 and a jig 422 made of a lattice-shaped reinforcing bar connected to the vibrator 421, similar to the vibration imparting device 20 in FIG. 3. The ultrasonic irradiation device 43 is provided at the bottom of the second container 421.

[0049] As the vibrator 421, a portable vibrator E32D (frequency 200 to 250 Hz) manufactured by Exen was used. As the ultrasonic irradiation device 43, a Phoenix Plus 26 kHz 1200 W manufactured by Kaijo Co., Ltd. was used. As shown in FIG. 4B, the length (B1×B2) in the predetermined direction×width direction of the first storage section 411 was 430 mm×430 mm. As the medium 3 to be stored in the second storage section 412, tap water or deaerated water at room temperature was used.

[0050] [Test 1. Fluidity of cement paste] Fig. 5 is a graph showing the results of Test 1 in which cement paste was used as a sample. First, in order to eliminate the influence of aggregate material, shape, size variation, and the like, cement paste without any aggregate mixed therein was selected as the sample. Ordinary Portland cement was used, and 3 liters of cement paste in a fluid state with a water to cement mass ratio (W / C) of 0.45 was supplied to the first storage unit 411. Note that samples were repeatedly prepared in batches of 3 liters each time they were required (the same was true for Test 2).

[0051] The increase (change) in flow value was measured before and after applying vibration or ultrasonic waves to the cement paste under each condition shown in Figure 5. The flow value was measured with reference to JIS R 5201 "Physical test methods for cement."

[0052] As a result, the increase in flow value was greater when the vibration of the vibration imparting device 42 was applied for 5 seconds and the ultrasonic wave of the same frequency (100 kHz) was applied for 60 seconds, compared with the case where only the vibration of the vibration imparting device 42 was applied for 5 seconds and the case where only the ultrasonic wave (100 kHz) was applied by the ultrasonic wave irradiation device 43 for 60 seconds. In other words, it was found that the increase in flow value was greater by using the vibration imparting device 42 and the ultrasonic wave irradiation device 43 in combination, compared with the case where only the vibration imparting device 42 or only the ultrasonic wave irradiation device 43 was used for fluidization, and the effect of improving the fluidity of the cement paste was higher. When the vibration imparting device 42 and the ultrasonic wave irradiation device 43 were used in combination, both devices 42 and 43 were started at the same time, and the ultrasonic wave irradiation device 43 irradiated ultrasonic waves for a longer period of time (this also applies to other tests described below). In addition, in this test, the output of the ultrasonic oscillator 44 of the ultrasonic wave irradiation device 43 was set to 1200 W.

[0053] Furthermore, a test was conducted in which the frequency of the ultrasonic irradiation device 43 was lowered to 38 kHz and the amplitude was increased. In this case, too, the combined use of the vibration imparting device 42 and the ultrasonic irradiation device 43 increased the increase in the flow value, and the effect of improving the fluidity of the cement paste was enhanced. Also, even in the case of using the vibration imparting device 42 and the ultrasonic irradiation device 43 in combination in the same manner, it was found that the increase in the flow value increased and the effect of improving the fluidity of the cement paste was further enhanced by lowering the frequency of the ultrasonic waves and increasing the amplitude.

[0054] [Test 2. Mortar fluidity] Figures 6 and 7 are graphs showing the results of Test 2, in which mortar was used as a sample. Next, the mass ratio (W / C) of water to cement (ordinary Portland cement) was 0.45, and the fine aggregate (Kisarazu land sand, surface dry density 2.59 g / cm 33 liters of mortar in a fluid state having a mass ratio (S / C) of 1.0 to cement was supplied to first container 411 .

[0055] The increase in flow value was measured before and after vibration and ultrasonic waves were applied to the mortar under each of the conditions shown in Figures 6 and 7. The flow value was measured with reference to JIS A 1171 "Test methods for polymer cement mortar."

[0056] As shown in FIG. 6, the same results as those of the cement paste (FIG. 5) were obtained for the mortar containing fine aggregate. In other words, the combined use of the vibration imparting device 42 and the ultrasonic irradiation device 43 increases the increase in the flow value and improves the fluidity of the mortar, compared to the case where the vibration imparting device 42 or the ultrasonic irradiation device 43 is used for fluidization alone. In other words, the combined use of the vibration imparting device 42 and the ultrasonic irradiation device 43 can shorten the time for applying ultrasonic waves to obtain the desired fluidity. In addition, from the results of FIG. 6, when the irradiation conditions (frequency (38 kHz), amplitude) of the ultrasonic irradiation device 43 are the same, the increase in the flow value is greater when the ultrasonic irradiation device 43 is irradiated for 300 seconds than when the ultrasonic irradiation device 43 is irradiated for 60 seconds, that is, when the irradiation time is extended, the increase in the flow value is greater and the fluidity is improved.

[0057] In addition, when only the vibration imparting device 42 was used, it was confirmed that the mortar instantly became fluid, but even when the vibration time was increased from 1 second to 10 seconds, the increase in the flow rate hardly changed, and the fluidity also increased only slightly. In addition, when the vibration time of the vibration imparting device 42 was increased, the phenomenon of material separation, such as the settling and coagulation of the fine aggregate, was visually confirmed.

[0058] When only the ultrasonic irradiation device 43 is used, as shown in Fig. 7, it was found that the flow increase amount increases and the fluidity of the mortar improves as the irradiation time is increased to 300 seconds and 600 seconds. However, when the irradiation time is longer than 600 seconds, the flow increase amount hardly changes even if the irradiation time is increased. It was also confirmed that the phenomenon of material separation occurs when the ultrasonic irradiation time is increased.

[0059] [Test 3. Fluidity of concrete] Fig. 8 is a graph showing the results of Test 3 in which concrete was used as a sample. Next, 40 liters of fluidized concrete with a water to cement (ordinary Portland cement) mass ratio (W / C) of 0.55 and a slump of 10 cm was produced, and 15 liters of the concrete was supplied to the first storage section 411. In addition, fine aggregate (Kisarazu land sand, surface dry density 2.59 g / cm 3 The mass ratio (S / C) of the coarse aggregate (Ome crushed stone, surface dry density 2.71 g / cm 3 ) and cement mass ratio (G / C) is 3.07.

[0060] The increase in slump was measured before and after vibration and ultrasonic waves were applied to the mortar under each condition shown in Figure 8. The slump was measured with reference to JIS A 1101:2020 "Slump test method for concrete".

[0061] From the results in Fig. 8, it was found that even in concrete containing fine aggregate and coarse aggregate, the combined use of the vibration imparting device 42 and the ultrasonic irradiation device 43 resulted in a greater increase in the slump value and a greater effect in improving the fluidity of the concrete, compared to the case of fluidizing the concrete using only the ultrasonic irradiation device 43. In other words, the combined use of the vibration imparting device 42 and the ultrasonic irradiation device 43 makes it possible to shorten the time for which ultrasonic waves are applied in order to obtain the desired fluidity.

[0062] Furthermore, it was found that even when the irradiation conditions (frequency (26 kHz), amplitude) of the ultrasonic irradiation device 43 were the same, the effect of improving fluidity differed depending on the medium 3. As shown in Fig. 8, the increase in slump value was greater and fluidity was improved more when 26 kHz ultrasonic waves were irradiated to concrete for a short time (60 seconds) via deaerated water at room temperature (medium 3) than when 26 kHz ultrasonic waves were irradiated to concrete for 180 seconds via tap water at room temperature (medium 3).

[0063] ===About improving liquidity with Liquidity Improvement System 1=== As described above, the fluidity improvement system 1 illustrated in Figures 1 and 2 includes a container 10 having a length in a predetermined direction, a first container section 11 for containing a fluidized cement composition 2 having aggregate, and a second container section 12 for containing a medium 3, a vibration imparting device 20 for imparting vibrations to the cement composition 2, and an ultrasonic irradiation device 30 for irradiating ultrasonic waves to the cement composition 2 via the medium 3.

[0064] The vibration imparting device 20 itself vibrates, and is inserted into the cement composition 2 to directly vibrate the cement composition 2. Therefore, the cement composition 2 is instantly fluidized by the action of the vibration imparting device 20. However, when the vibration imparting device 20 is stopped, the fluidity of the cement composition 2 also decreases.

[0065] On the other hand, it has been confirmed that when ultrasonic waves are irradiated to the cement composition 2 to impart ultrasonic vibrations, the fluidity of the cement composition 2 is improved and the continuity of the fluidity is increased. However, if one attempts to improve the fluidity of a large amount of cement composition used in actual construction using only the ultrasonic irradiation device 30, a very large amount of ultrasonic energy is required.

[0066] In contrast, according to the fluidity improving system 1 of the present embodiment, ultrasonic waves can be irradiated while vibration is applied to the fluidized cement composition 2. Therefore, ultrasonic waves can be applied while instantaneously breaking up the aggregates of the cement composition 2 by the vibration applying device 20, so that the fluidity of the cement composition 2 can be improved with smaller ultrasonic energy than when only ultrasonic waves are applied. In the above-mentioned tests 1 to 3 that were actually performed, it was confirmed that the fluidity of the cement composition was further improved by using the vibration applying device 2 and the ultrasonic irradiation device 3 in combination. Therefore, the ultrasonic irradiation device 30 can be made smaller and the ultrasonic irradiation time can be shortened.

[0067] As described above, according to the fluidity improving system 1 of this embodiment, the fluidity of the cement composition 2 can be efficiently improved in a short time, and therefore the system can be implemented in actual construction where the fluidity of a large amount of the cement composition 2 must be improved in a short time. In addition, by applying ultrasonic waves to the cement composition 2, the durability of the fluidity of the cement composition 2 is increased. Therefore, the cement composition 2 can be easily spread uniformly in the pouring location (within the formwork) of the cement composition 2.

[0068] Furthermore, in the case of the cement composition 2 containing aggregate, the problem of settling and coagulation (i.e., material separation) of the aggregate can be suppressed by shortening the time for which vibration or ultrasonic waves are applied. Therefore, the cement composition 2 in which the material is homogenized can be delivered to the casting site.

[0069] In addition, an ultrasonic irradiation device 30 is attached to the bottom of the first container 11, and ultrasonic waves are not directly emitted to the first container 11 but are propagated to the cement composition 2 via the medium 3. Therefore, damage to the first container 11 can be suppressed.

[0070] The frequency of the ultrasonic waves may be appropriately determined depending on the composition of the cement composition. The frequency of the ultrasonic waves to be irradiated is preferably 10 to 200 kHz, more preferably 15 to 100 kHz, and even more preferably 19 to 50 kHz. By setting the frequency of the ultrasonic waves within the above numerical range, the fluidity of the cement composition 2 can be improved.

[0071] The amplitude of the irradiated ultrasonic waves is preferably 5 to 50 μm, more preferably 5 to 40 μm, further preferably 5 to 35 μm, and particularly preferably 6 to 30 μm. By setting the amplitude of the ultrasonic waves to the lower limit of the above-mentioned numerical range or more, the fluidity of the cement composition 2 can be improved in a shorter time, and by setting the amplitude to the upper limit of the above-mentioned numerical range or less, the risk of the aggregate settling and coagulating in the cement composition can be further reduced.

[0072] The output of the ultrasonic oscillator 31 used in the ultrasonic irradiation device 30 is preferably 10 to 3000 W, and may be appropriately set according to the mass of the target cement composition 2. In other words, the output of the ultrasonic waves should be increased as the mass of the cement composition 2 to be treated increases. In a test by the applicant, an output of 1200 W was evaluated for 10 to 20 liters of the cement composition 2, and it was confirmed that the fluidity was improved. The ultrasonic irradiation time is preferably 0.1 to 30 minutes, and more preferably 0.1 to 10 minutes.

[0073] Water is exemplified as the medium 3 for propagating ultrasonic waves, but is not limited thereto. The medium 3 may be a liquid other than water, a gel-like substance, or the like. The second container 12 may have any shape and arrangement in which the medium 3 is in contact with the first container 11. The first container 11 may be formed of a material capable of propagating ultrasonic waves to the cement composition 2 therein, and may be, for example, steel or other metal materials. In the cross-sectional view of FIG. 2, the medium 3 is provided only below the first container 11, but the medium 3 may also be filled inside the side wall that divides the first container 11 in the width direction, and ultrasonic waves may also be irradiated from the width direction.

[0074] 1 and 2 has a length in a predetermined direction, and the cement composition 2 flows from one side to the other side of the first container 11 in the predetermined direction. Furthermore, it is preferable that the ultrasonic irradiation device 30 is provided continuously or intermittently from a position corresponding to one side to a position corresponding to the other side of the first container 11 in the predetermined direction. Although FIG. 2 illustrates an example of an ultrasonic irradiation device 30 that extends continuously in a predetermined direction, a plurality of ultrasonic irradiation devices 30 may be provided at intervals in the predetermined direction.

[0075] According to the above, ultrasonic waves can be applied during the period during which the cement composition 2 flows from one side to the other side in the predetermined direction, thereby improving the fluidity of the cement composition 2. In this case, the ultrasonic wave application time can be adjusted depending on the time during which the cement composition 2 flows in the predetermined direction (the flow speed and the length of the first container 11 in the predetermined direction).

[0076] The position corresponding to one side or the other side of the first storage section 11 in the predetermined direction refers to an end of one side or the other side when the first storage section 11 is divided into three in the predetermined direction. The ultrasonic irradiation device 30 may be disposed from any position on the end on one side to any position on the end on the other side.

[0077] 1 extends longer in the predetermined direction than in the width direction perpendicular to the predetermined direction, but is not limited thereto. The container 10 may have the same length in the predetermined direction and the width direction, or may have a length in the predetermined direction shorter than the length in the width direction, as in the container 41 illustrated in FIG. 4. The cement composition 2 does not have to flow in the predetermined direction, and may be subjected to vibration or ultrasonic waves in a stored state, as in the cement composition 2 in the container 41 illustrated in FIG. 4.

[0078] Furthermore, when the cement composition 2 flows from one side to the other side in the predetermined direction of the first container 11, it is preferable that the vibration imparting device 20 is provided on one side in the predetermined direction of the first container 11. Specifically, it is preferable that the vibration imparting device 20 is provided on one side (upstream side) of the center of the first container 11 in the predetermined direction.

[0079] By doing so, vibration can be applied to the cement composition 2 by the vibration applying device 20 at the stage when the cement composition 2 starts to flow through the first container 11. Therefore, ultrasonic waves can be irradiated to the cement composition 2 that has been instantaneously deaggregated by the vibration applying device 20. Therefore, the effect of improving the fluidity by ultrasonic waves can be enhanced compared to the case where ultrasonic waves are irradiated to the cement composition 2 that has a relatively low fluidity before vibration is applied. In addition, the state in which the fluidity is improved by the vibration applying device 20 is easily maintained by the irradiation of ultrasonic waves.

[0080] Furthermore, it is preferable that the vibration imparting device 20 and the ultrasonic irradiation device 30 overlap in a predetermined direction. In this way, the vibration imparting device 20 can impart vibration to the cement composition 2 and irradiate it with ultrasonic waves at the same time. Therefore, ultrasonic waves can be irradiated to the cement composition 2 in a state in which the aggregates have been deflocculated by the vibration imparting device 20, so that the effect of improving the fluidity by ultrasonic waves can be further enhanced.

[0081] However, without being limited to the above, the vibration imparting device 20 may be provided at the center in a predetermined direction or on the other side (downstream side) of the first storage section 11. Furthermore, the vibration imparting device 20 and the ultrasonic irradiation device 30 may be arranged offset in a predetermined direction.

[0082] In addition, as shown in Figure 1, the fluidity improvement system 1 desirably has a ready-mix concrete truck 50 (agitator truck, mixer truck) which is a supply device that supplies the cement composition 2 in a fluid state to the first storage section 11, and a pump truck 60 which is a delivery device that receives the cement composition 2 from the first storage section 11 and delivers it to the casting site.

[0083] By doing so, vibration and ultrasonic waves can be applied to the cement composition 2 during the period in which the cement composition 2 is moved from the ready-mix concrete truck 50 to the pump truck 60, thereby improving the fluidity of the cement composition 2. Then, the cement composition 2 having improved fluidity and having a high degree of fluidity that is highly sustainable can be delivered to the casting site.

[0084] As shown in FIG. 2, the first storage section 11 is desirably inclined downward from the ready mixed concrete truck 50 side (one side) toward the pump truck 60 side (the other side) in a predetermined direction.

[0085] This allows the cement composition 2 to flow in a predetermined direction by gravity, and the cement composition 2 can be transported to the pump vehicle 60. In this case, the cement composition 2 can be made to flow in a predetermined direction even without a transport mechanism 70 illustrated in Fig. 9 described later, and the configuration of the fluidity improving system 1 can be simplified.

[0086] Fig. 9 is an explanatory diagram of a modified example of the fluidity improving system 1. The fluidity improving system 1 may have a conveying mechanism 70 that conveys the cement composition 2 in the first storage section 11 from the ready-mix concrete truck 50 side (one side) to the pump truck 60 side (the other side) in a predetermined direction. Fig. 9 illustrates, as an example of the conveying mechanism 70, a conveying mechanism 70 in which the bottom of the first storage section 11 is a conveying belt 71. The conveying belt 71, which moves by the rotation of a conveying roller 72, can convey the cement composition 2 in a predetermined direction.

[0087] By providing the fluidity improving system 1 with the conveying mechanism 70 in this manner, the cement composition 2 can be made to flow in a predetermined direction, and vibration and ultrasonic waves can be applied to the cement composition 2 during this flow. In this case, the container 10 may be aligned horizontally as shown in FIG. 9. Alternatively, the conveying mechanism 70 may be provided in the inclined container 10 shown in FIG. 2. Furthermore, the speed at which the cement composition 2 is conveyed by the conveying mechanism 70 can be adjusted. Therefore, the time for which ultrasonic waves are irradiated to the cement composition 2 flowing through the first container 11 can be adjusted, making it easier to adjust the fluidity of the cement composition 2.

[0088] As shown in FIG. 3, the vibration imparting device 20 has an oscillator 21 (eg, a rod-shaped vibrator) and a jig 22 that is vibrated by the oscillator 21 and that extends in the planar direction of the cement composition 2.

[0089] Vibrations may be applied to the cement composition 2 only by the vibrator 21 such as a rod-shaped vibrator. In that case, vibrations are applied to the cement composition 2 around the vibrator 21, but the vibrations are difficult to propagate to the cement composition 2 in areas away from the vibrator 21. Therefore, by using a jig 22 that spreads in a plane direction perpendicular to the vibrator 21, the jig 22 can be brought into contact with the cement composition 2 over a wide range in the plane direction (direction along the surface) of the cement composition 2, and the vibrations can be propagated via the jig 22.

[0090] 3 shows an example of the jig 22 in which reinforcing bars are arranged in a lattice pattern, but the shape and material of the jig 22 are not particularly limited as long as they can propagate vibration in the planar direction. As shown in FIG. 1, the width of the jig 22 is desirably approximately the same as the width of the first container 11 (direction perpendicular to the predetermined direction). This allows vibration to be applied to the cement composition 2 regardless of the position in the width direction in which it flows through the first container 11.

[0091] 10A and 10B are explanatory diagrams of a modified example of the fluidity improvement system 1. In actual construction, the cement composition 2 is often supplied from the ready-mix concrete truck 50 to the first storage section 11 for a long period of time. When ultrasonic waves are irradiated to the cement composition 2 that continues to flow through the first storage section 11, the operating time of the ultrasonic irradiation device 30 becomes longer, heat is generated, and the temperature of the medium 3 also increases. In general, when the temperature of a fluid increases, the fluid expands and the density decreases. This reduces the ultrasonic vibrations propagated by the medium 3, and the efficiency of ultrasonic irradiation decreases.

[0092] Therefore, the fluidity improvement system 1 may have at least one of a cooling device 81 for cooling the medium 3 and a circulation device 82 for circulating the medium 3. This can prevent the temperature of the medium 3 from increasing due to the heat generated by the operation of the ultrasonic irradiation device 30, and can prevent the density of the medium 3 from decreasing. Therefore, the ultrasonic vibration is less likely to be reduced, and the ultrasonic waves can be efficiently propagated to the cement composition 2. This can further improve the fluidity of the cement composition 2, reduce the size of the ultrasonic irradiation device 30 or the output of the ultrasonic oscillator 31, and shorten the ultrasonic irradiation time.

[0093] Fig. 10A shows an example of a fluidity improving system 1 having a cooling device 81. In the cooling device 81 of Fig. 10A, a flow path pipe 811 through which cooling water or a refrigerant flows is provided in the second storage unit 12. The flow path pipe 811 can lower the temperature of the medium 3 in the second storage unit 12. The configuration of the cooling device 81 is not particularly limited, and examples include a device having a cooling cycle consisting of a compressor, a condenser, an expansion valve, and an evaporator, and a device that uses a pump to flow cooling water cooled by ice or the like through the flow path pipe 811.

[0094] 10B shows an example of the fluidity improving system 1 having a circulation device 82. The circulation device 82 has a discharge flow path 821 for discharging the medium 3 in the second storage unit 12, a tank 822 for storing the medium 3 that has flowed through the discharge flow path 821, a pump 823, and a supply flow path 824 for the medium 3 that flows from the tank 822 to the second storage unit 12 by the pump 823. The temperature of the medium 3 discharged from the second storage unit 12 decreases while it is away from the ultrasonic irradiation device 3, and the temperature of the medium 3 supplied to the second storage unit 12 can be decreased. However, the configuration of the circulation device 82 is not limited to that exemplified in FIG. 10B.

[0095] Even if the ultrasonic irradiation device 30 is not operated for a long period of time, the density of the medium 3 can be increased by lowering the temperature of the medium 3 with the cooling device 81, and ultrasonic waves can be efficiently propagated to the cement composition 2. The temperature of the medium 3 is desirably in the range from a temperature higher than the freezing point of the medium 3 to below room temperature. When the medium 3 is water, the maximum density is reached at 4°C (3.98°C to be precise), so it is desirable to keep the temperature of the medium 3 at about 4°C.

[0096] Furthermore, the fluidity improving system 1 may include both the cooling device 81 and the circulation device 82. Although not shown, for example, the medium 3 stored in the tank 822 in the circulation device 82 of Fig. 10B may be cooled by the cooling device. By doing so, the temperature of the medium 3 supplied to the second storage unit 12 can be lowered more reliably.

[0097] In addition, it is preferable that the medium 3 is degassed water (a degassed liquid from which dissolved gas has been removed). By doing so, the density of the medium 3 can be increased, and ultrasonic waves can be efficiently propagated to the cement composition 2, as compared with the case where the medium 3 is tap water, for example. This makes it possible to further improve the fluidity of the cement composition 2, reduce the size of the ultrasonic irradiation device 30 and the output of the ultrasonic oscillator 31, and shorten the ultrasonic irradiation time. In order to make the medium 3 degassed water, for example, it is preferable to seal the degassed water in the second container 12 or provide a degassing device in the circulation path of the medium 3 shown in FIG. 10B.

[0098] As described above, it is preferable that the medium 3 for propagating ultrasonic waves is low temperature (lower than room temperature) and deaerated water. This can further improve the fluidity of the cement composition 2. The fact that deaerated water improves fluidity has also been confirmed by the results of Test 3 in FIG. 8.

[0099] ===Method for improving fluidity of cement composition 2=== FIG. 11 is a diagram showing a flow of the method for improving the fluidity of the cement composition 2. The method for improving the fluidity of a cement composition 2 of this embodiment includes a vibration imparting step (S02) of imparting vibration to the cement composition 2 having aggregate in a fluid state, and an ultrasonic irradiation step (S02) of irradiating the cement composition 2 with ultrasonic waves via a medium 3 such as water.

[0100] By doing so, the fluidity of the cement composition 2 can be improved with smaller ultrasonic energy than when only the vibration applying step or only the ultrasonic irradiation step is included. Therefore, the ultrasonic irradiation device 30 can be made smaller and the ultrasonic irradiation time can be shortened. In addition, the ultrasonic irradiation step enhances the durability of the fluidity of the cement composition 2.

[0101] Also, vibration or ultrasonic waves are applied to the fluidized cement composition 2. For this reason, it is advisable to provide a supplying step (S01) of supplying the fluidized cement composition 2 that has already been mixed in a factory to a container such as the first container section 11 in Fig. 2, prior to the vibration applying step and the ultrasonic irradiation step. By doing so, the fluidity of the cement composition 2 that is already in a fluidized state can be further improved.

[0102] The cement composition 2 whose fluidity has been improved by the vibration applying step and the ultrasonic irradiation step may be delivered from the container to a pump truck or a casting site. In this way, the cement composition 2 whose fluidity has been improved can be delivered to the casting site.

[0103] Furthermore, it is desirable that the ultrasonic irradiation step overlaps with the vibration applying step for a certain period of time, so that vibration and ultrasonic waves can be applied simultaneously to the cement composition 2. In other words, ultrasonic waves can be applied to the cement composition 2 in a state in which the aggregation has been deflocculated by the vibration applying step, and the effect of improving the fluidity by ultrasonic waves can be further enhanced.

[0104] Preferably, the vibration applying step is performed simultaneously in the first half of the ultrasonic irradiation step. By doing so, the cement composition 2 in a deaggregated state can be irradiated with ultrasonic waves for a longer period of time. However, without being limited to the above, the ultrasonic irradiation step and the vibration applying step may be performed at different times without overlapping, or the vibration applying step may be performed in the second half of the ultrasonic irradiation step.

[0105] In addition, in the ultrasonic irradiation step, the ultrasonic irradiation time is preferably 600 seconds or less. This allows for more energy saving than when the ultrasonic irradiation time is longer than 600 seconds. In addition, in the test 2 of FIG. 7, even if ultrasonic irradiation is performed for longer than 600 seconds, the fluidity of the mortar is not easily improved. Therefore, by setting the ultrasonic irradiation time to 600 seconds or less, the fluidity of the cement composition 2 is improved while material separation of the cement composition 2 (aggregation or sedimentation of aggregate) caused by an irradiation time longer than necessary can be suppressed.

[0106] In addition, in the vibration applying step, it is desirable that the time for applying vibration to the cement composition 2 is less than 60 seconds. This can save energy compared to the case where the vibration is applied for 60 seconds or more. In addition, in the test 2 of FIG. 6, the result was that the fluidity of the cement composition 2 after the device was stopped was almost the same whether the vibration was applied for 1 second or 10 seconds by the vibration applying device 42. Therefore, by setting the vibration application time to less than 60 seconds, it is possible to improve the fluidity of the cement composition 2 while suppressing material separation of the cement composition 2 caused by an excessively long vibration time.

[0107] In addition, similarly to the above-mentioned fluidity improving system 1, in the method for improving the fluidity of the cement composition 2, the medium 3 for propagating ultrasonic waves is desirably at a low temperature (lower than room temperature) and deaerated water. For this purpose, the vibration applying step and the ultrasonic irradiation step may be performed while a step of cooling the medium 3 or circulating the medium 3 is also included. In addition, the vibration applying step and the ultrasonic irradiation step may be performed during the period in which the cement composition 2 is flowed from the ready-mix concrete truck 50 toward the pump truck 60.

[0108] The above-mentioned embodiment is intended to facilitate understanding of the present invention, and is not intended to limit the present invention. The present invention can be modified or improved without departing from the spirit of the present invention, and it goes without saying that the present invention includes equivalents thereof. [Explanation of symbols]

[0109] 1 Liquidity Improvement System, 2 cement composition, 3 medium, 10 containers, 11 first storage section, 12 second storage section, 20 Vibration imparting device, 21 transducer, 22 fixture, 30 Ultrasonic irradiation device, 31 Ultrasonic oscillator, 40 Test equipment (fluidity improvement system), 41 container, 411 first storage section, 412 second storage section, 42 Vibration device, 421 Transducer, 422 Fixture, 43 Ultrasonic irradiation device, 44 Ultrasonic oscillator, 50 feeding equipment; 60 Delivery device, 70 Conveying mechanism, 81 Cooling equipment, 82 Circulation equipment,

Claims

1. A container having a first container portion for containing a fluidized cement composition having aggregate and a second container portion for containing a medium, the container having a length in a predetermined direction; A vibration imparting device that imparts vibration to the cement composition; An ultrasonic irradiation device that irradiates ultrasonic waves to the cement composition through the medium; A system for improving the fluidity of a cement composition, comprising:

2. The fluidity improving system for a cement composition according to claim 1, The cement composition flows from one side to the other side of the first container in the predetermined direction, The system for improving the fluidity of a cement composition is characterized in that the ultrasonic irradiation device is installed continuously or intermittently from a position corresponding to the one side of the specified direction of the first container to a position corresponding to the other side.

3. The fluidity improving system for a cement composition according to claim 1 or 2, The cement composition flows from one side to the other side of the first container in the predetermined direction, A system for improving the fluidity of a cement composition, characterized in that the vibration imparting device is provided on one side of the first container in the specified direction.

4. The fluidity improving system for a cement composition according to claim 1 or 2, A supply device that supplies the cement composition in a fluid state to the first storage portion; A delivery device that receives the cement composition from the first storage portion and delivers it to a casting location; A system for improving the fluidity of a cement composition, comprising:

5. The fluidity improving system for a cement composition according to claim 4, The system for improving fluidity of a cement composition, wherein the first storage section is inclined downward from the supply device side toward the delivery device side in the predetermined direction.

6. The fluidity improving system for a cement composition according to claim 4, A system for improving the fluidity of a cement composition, comprising a conveying mechanism for conveying the cement composition in the first storage section from the supply device side to the delivery device side in the specified direction.

7. The fluidity improving system for a cement composition according to claim 1 or 2, The system for improving the fluidity of a cement composition is characterized in that the vibration imparting device has a jig that is vibrated by a vibrator and extends in the surface direction of the cement composition.

8. The fluidity improving system for a cement composition according to claim 1 or 2, A system for improving fluidity of a cement composition, comprising at least one of a cooling device for cooling the medium and a circulation device for circulating the medium.

9. The fluidity improving system for a cement composition according to claim 1 or 2, A system for improving the fluidity of a cement composition, wherein the medium is a degassed liquid.

10. A vibration applying step of applying vibration to a fluidized cement composition containing aggregate; an ultrasonic irradiation step of irradiating the cement composition with ultrasonic waves through a medium; A method for improving the fluidity of a cement composition, comprising the steps of:

11. The method for improving fluidity of a cement composition according to claim 10, A method for improving the fluidity of a cement composition, wherein the ultrasonic irradiation step has a period overlapping with the vibration application step.

12. A method for improving fluidity of a cement composition according to claim 10 or 11, A method for improving the fluidity of a cement composition, characterized in that in the ultrasonic irradiation step, the ultrasonic irradiation time is 600 seconds or less.

13. A method for improving fluidity of a cement composition according to claim 10 or 11, A method for improving the fluidity of a cement composition, wherein in the vibration applying step, the cement composition is subjected to vibration for a period of less than 60 seconds.

Images