JP2715251B2 - Method and apparatus for measuring physical properties of substance liquefied by vibration - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for measuring the physical properties of a substance which is liquefied by vibration and exhibits the properties of a viscoelastic body, such as ultra-hard concrete.

[0002]

2. Description of the Related Art Vibration compaction, in which vibration and overburden are applied simultaneously, is used for the formation of ultra-hard concrete that has a unit water volume significantly smaller than that of ordinary concrete (water / cement ratio is about 40% or less). (See, for example, Japanese Patent Publication No. 45-36305, Japanese Utility Model Publication No. 57-42635, and Japanese Patent Application Laid-Open No. 2-25303). According to this method, since the amount of cement paste can at least reduce the interval between aggregates and increase the adhesive strength, the required strength can be obtained with a small amount of cement, and the quality of the concrete itself can be improved. It is also very advantageous for factory production, such as economy due to immediate demolding, adaptability to diversification of production, and adaptability to automation of production.

Various methods for measuring physical properties (viscous resistance, workability, etc.) of ordinary concrete have already been proposed, and few are satisfactory, but a certain degree of accuracy has been obtained. However, the measurement method used for ordinary concrete can be realized because the fresh concrete itself flows into a liquid state from the beginning. It cannot be applied to ultra-hard concrete that does not liquefy unless it is done. It is almost meaningless to grasp the physical properties of the ultra-hardened concrete in the state of powder before vibration compaction, and the properties can only be grasped by dynamically capturing the physical properties in the vibration compaction process. .

[0004] Despite the advantages of ultra-hardened concrete as described above, there has been no method for measuring the physical properties during the vibration compaction process. The choice of materials had to rely on human experience and intuition.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to dynamically and easily determine the properties of a substance which is liquefied by vibration to exhibit the properties of a viscoelastic body, such as super-hardened concrete, in a vibration compaction process. It is an object of the present invention to provide a measuring method and a measuring device which can perform measurement at a time.

[0006]

According to the measuring method of the present invention, a substance to be liquefied by vibration is put in a container, a suspended sphere is embedded in the substance, and a load and vibration are applied to the substance. While detecting the vertical displacement of the sphere and the vibration in or through the material. In the present invention, the “sphere” is not limited to a literal sphere,
It also includes a deformed sphere (for example, an elliptical sphere) and a polyhedron.

[0007] Preferably, vibrations in the substance are detected by a sensor attached to the spherical body. If the weight of the spherical body is balanced with the weight of the balance weight and the weight of the spherical body in the air is set to zero, the spherical body can be floated by the buoyancy when the substance in the container is liquefied. The sphere may be pulled up in the material with a constant pulling force.

[0008] An overload can be applied to the substance by means of a pressurizing body which is vertically displaceable with respect to the container. In this case, the vertical displacement of the pressing body is directly or indirectly detected. Also, if the vibration of the pressurized body is detected, the vibration that has propagated the substance can be detected indirectly. The material can be vibrated by vibrating the container with a vibrator.
In this case, the excitation vibration of the vibrator is detected so that the vibration can be compared with the vibration in or through the substance.

A measuring apparatus according to a first embodiment of the present invention comprises a container having an upper surface opened to contain a substance to be liquefied by vibration, a vibrator for applying vibration to the container, and a vibrator for applying an overload to the substance in the container. A pressurized body that can be displaced vertically with respect to the container, a spherical body with a built-in sensor that detects vibration,
A suspending mechanism that suspends the spherical body so as to be vertically displaceable in a state of being embedded in the substance in the container, and an equilibrium weight that balances the weight with the spherical body through the suspending mechanism,
A first displacement sensor for indirectly detecting the vertical displacement of the spherical body outside the container by detecting the vertical displacement of the balance weight or the suspension mechanism; And a second displacement sensor for detecting.

[0010] A measuring apparatus according to a second embodiment of the present invention comprises a container having an upper surface opened to contain a substance to be liquefied by vibration, a vibrator for applying vibration to the container, and a vibrator for applying an overload to the substance in the container. A pressurizing body that is vertically displaceable with respect to the container, a spherical body, a suspending mechanism that suspends the spherical body so as to be vertically displaceable while being embedded in a substance in the container, and a suspending mechanism that suspends the spherical body. The lifting weight that applies a constant lifting force to the spherical body via the lowering mechanism, and the vertical displacement of the spherical body is detected outside the container by detecting the vertical displacement of the lifting weight or the suspending mechanism. The first to detect indirectly
, A second displacement sensor for detecting the vertical displacement of the pressurizing body, and a sensor for detecting the vibration of the pressurizing body.

[0011]

When the substance in the container is liquefied by being subjected to an overload and vibration, the suspended spheres rise in the substance after descending or once without descending. When this displacement is detected outside the container and the vibration of the substance is detected at the same time, the process of liquefaction is captured every moment from both the change in the amplitude and the change in the movement of the spherical body, and the timing of the onset of liquefaction is determined. In addition to being able to estimate it, it can also dynamically grasp the progress of compaction and changes in viscosity, and in the case of concrete, know the relationship between the timing of liquefaction due to vibration compaction and workability, etc. be able to. In addition, since the speed is obtained from the displacement of the spherical body, it becomes possible to measure the viscosity coefficient and the like in the compaction process. Further, by changing conditions such as the frequency and intensity of the applied vibration and, in the case of concrete, the ratio of water / cement, the relationship with the conditions can be known.

Further, by detecting the displacement of the pressurized body to which the load is applied, the completion time of compaction can be estimated from the attenuation of the sedimentation velocity of the pressurized body, and the amplitude of vibration of the material and the spherical body can be estimated. In addition to the two factors of displacement, the factor of displacement of the pressurized body (settling velocity) is also added, which makes it more accurate and easy to estimate the timing of the onset of liquefaction, grasp the progress of compaction, and determine workability. .

Both the displacement of the spherical body and the displacement of the pressurized body can be detected outside the container. In addition, when vibration is detected by a sensor attached to the spherical body, the vibration in the substance at the current position of the spherical body suspended vertically displaceably will be directly detected. When vibration is detected by a sensor provided on the body, vibration transmitted through a substance is indirectly detected outside. That is, the detection of both the displacement of the spherical body, the displacement of the pressurized body, and the vibration of the substance,
As in the case of the actual molding of the ultra-hardened concrete, the container can be closed with a pressurized body instead of the mold and kept in a closed state, so that the measurement in accordance with the actual molding process can be performed.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention and experimental results thereof will be described below with reference to the drawings.

FIG. 1 shows a measuring apparatus according to a first embodiment of the present invention. In this measuring apparatus, a container 3 is fixed on a vibration table 2 on which a pair of vibrators 1 are mounted, a spherical body 4 is suspended from a frame (not shown) by a suspension mechanism 5, and a pressurizing body 6 is suspended. It is suspended from the same frame by the lowering mechanism 7. The vibration table 2 has a base 10 via a plurality of dashpots (buffer brakes) 8 using a pneumatic cushion and a plurality of support springs 9.
It is supported horizontally on top. When the vibration table 2 is vibrated by the vibrator 1, the container 3 also vibrates integrally therewith. In this example, the container 3 is a model of a concrete molding die, and has a vertically long cylindrical shape with an open top and is divided into two so that the hardened concrete can be easily taken out. It has a structure.

The pressurizing member 6 is a thick disk having an outer diameter slightly smaller than the inner diameter of the container 3 and can be freely inserted into the container 3 while being suspended by the suspension mechanism 7. At the center of the pressure body 6, a small hole 11 penetrating vertically is provided.

The suspension mechanism 7 includes a first
The two sets of two pulleys 12 are supported on the same axis, the second set of two pulleys 13 are also supported on the same axis, and two wires 14 are connected to the two sets of pulleys. The lower ends of the two vertical portions 14a of the wire 14 hanging from the two pulleys 12 of the first set are connected to the upper surface of the pressurizing body 6, and these two vertical While the pressurizing body 6 is suspended so as to be able to be held in a horizontal state by the portions 14a, the other two vertical portions 14b of the wire 14 hanging from the two pulleys 13 of the second set.
Reference numeral 14b denotes a hanging carriage 15 hung on a portion continuous in a U-shape. A weight 16 for adjusting the mounted load can be removably suspended on the shaft 16 of the lifting wheel 15. A spring 1 is provided between two vertical portions 14a of the wire 14 hanging from the first pair of pulleys 12 in order to insulate vibration transmitted from the pressurizing body 6.
8.18 are interposed.

On the other hand, the suspension mechanism 5 for the spherical body 4 hangs a single wire 21 on the two pulleys 19 and 20 pivotally supported by the above-mentioned frame, and attaches the vertical portion 21a of the wire 21 suspended from the pulley 19 The spherical body 4 is connected to the lower end of the vertical portion 21a by being inserted into the hole 11 of the pressurizing body 6, and the pulley 20 is used to reduce the weight of the spherical body 4 in the air to zero.
An equilibrium weight 22 is detachably connected to the lower end of a vertical portion 21b of a wire 21 hanging down from the wire. Pulley 19
A spring 23 is interposed in the middle of the vertical portion 21a of the wire 21 hanging down from the wire 21 to insulate the vibration transmitted from the spherical body 4.

The spherical body 4 has a first vibration sensor 24 for detecting vibration in concrete inside a plastic or metal sphere having a smooth surface. On the upper surface of the pressurizing body 6, a second vibration sensor 25 for detecting vibration transmitted through the concrete is attached,
Further, a third vibration sensor 26 is mounted on the vibration table 2 to detect the excitation vibration of the vibrator 1. In this example, acceleration sensors are used as the vibration sensors 24, 25, and 26.

A first laser displacement meter 27 for detecting the amount of displacement of the balance weight 22 in the vertical direction is provided on the frame.
And a second laser displacement meter 28 for detecting the amount of vertical displacement of the weight 17 for adjusting the mounting load are fixed at predetermined height positions. The balance weight 22 rises by the amount of displacement when the spherical body 4 descends, and falls by the amount of displacement when the spherical body 4 rises.
Means that the amount of vertical displacement of the spherical body 4 is indirectly detected outside the container 3. In addition, the weight 1 for adjusting the loading load 1
7 is such that when the pressure body 6 is lowered, it rises by the displacement amount, and when the pressure body 6 rises, it falls by the displacement amount.
Is indirectly detecting the amount of vertical displacement of the pressure body 6.

In order to measure the physical properties of ultra-hard concrete using the measuring device shown in FIG. The wire 21 is temporarily fixed outside the container 3 so that the sphere 4 maintains a suspended state at a predetermined height position in the empty container 3. In this state, the granular fresh concrete 29 is put into the container 3, and when the spherical body 4 is completely embedded in the fresh concrete 29, the fixing of the wire 21 is released to release the spherical body 4 into the fresh concrete 29. Then, the fresh concrete 29 is put into the container 3 to a predetermined height. Then, after starting the vibrator 1, the pressurizing body 6 is placed on the fresh concrete 29, and the vibration in the concrete 29 is detected by the vibration sensor (acceleration sensor) 24 while compacting the concrete 29 in the container 3 by vibration. The vibration of the pressurizing body 6 is detected by a vibration sensor (acceleration sensor) 25, the vibration of the vibration table 2 is detected by a vibration sensor (acceleration sensor) 26, and the vertical displacement of the balance weight 22 is measured by a laser displacement meter 27. Then, the vertical displacement of the weight 17 for adjusting the load is measured by the laser displacement meter 28.
Respectively.

Next, a measuring apparatus according to a second embodiment of the present invention shown in FIG. 2 will be described. This measuring apparatus differs from the measuring apparatus of the first embodiment shown in FIG. 1 in the following points. That is, in the example of FIG. 1, the spherical body 4 having the built-in vibration sensor 24 is used, and this is balanced with the balance weight 22. However, in the example of FIG. 2, a simple sphere (for example, a steel ball) without the vibration sensor is used.
Is used. Further, in order to enable the spherical body 30 to be forcibly pulled up by a predetermined lifting force, a lifting weight 31 is used in addition to the balance weight 22. A load cell 32 for electrically detecting the load of the lifting weight 31 and a load for displaying the detected load are provided between the vertical portions 21a of the wires 21 connecting the weights 22 and 31 and the spherical body 30. 33 in total.
Since the load meter 33 has a spring, vibration transmitted from the spherical body 30 can be insulated by the spring. The vibration of the pressure body 6 and the vibration of the vibration table 2 are detected by the vibration sensors 25 and 26, respectively, as in the example of FIG.

The following describes how to measure the physical properties of the ultra-hard concrete using the measuring device shown in FIG. The wire 21 is temporarily fixed outside the container 3 so that the spherical body 30 maintains a suspended state at a predetermined height position in the empty container 3. In this state, the granular fresh concrete 29 is put into the container 3 to a predetermined height, and the spherical body 30
Is completely embedded in the fresh concrete 29.
Then, after the vibrator 1 is started, the pressurizing body 6 is placed on the fresh concrete 29, and while the concrete 29 in the container 3 is compacted by vibration, the vibration of the pressurizing body 6 is detected by a vibration sensor (acceleration sensor) 25. Then, the excitation vibration of the vibrator 1 is detected by the vibration sensor 26, respectively. When it is estimated that the compaction of the concrete 29 has progressed to some extent and the sedimentation of the pressurized body 6 has ended, the fixing of the wire 21 is released to release the spherical body 30 into the concrete 29, and the spherical body 30 is released.
The laser displacement meter 27 detects the vertical displacement of the lifting weight 31 while forcibly pulling up the concrete 29 by the load of the lifting weight 31 and the buoyancy acting on the spherical body 30, and the vibration sensor The vibration is continuously detected by 25 and 26.

An experiment was conducted by the above-described method using the measuring apparatus having the structure shown in FIG. In this case, the diameter of the spherical body 4 38.
0mm, volume 28.73cc, weight 45g, density 1.5
7 g / cm ³ . The buoyancy of the spherical body 4 in concrete is 70 gf. The inner diameter (diameter) of the container 3
150 mm, the weight of the pressurizing body 6 was 13.5 kg, and the applied pressure was 0.038 kg /
cm ² . And fresh concrete 2
9, the acceleration was measured by the vibration sensors 24, 25 and 26, the vertical displacement of the spherical body 4 was measured by the laser displacement meter 27, and the pressure Vertical displacement was measured simultaneously. However, the amount of the fresh concrete 29 is about 30 in height in the container 3 for any water / cement ratio.
It was set to about 0 mm.

FIGS. 3 to 7 show detected waveforms. FIG. 3 shows a case where the water / cement ratio of the fresh concrete 29 is 35%, FIG. 4 shows a case where the water / cement ratio is 36%, FIG.
Is 40%, and FIG. 7 is 42%. In each case, the vibration frequency of the vibrator 1 is 85 Hz, the excitation acceleration is 12 G, and the measurement is performed for 350 seconds from the start of the introduction of the fresh concrete 29. It was done. In these figures, the horizontal axis indicates the vibration compaction time from the start of the introduction of the fresh concrete 29, and the vertical axis indicates the height of the detected waveform, and (1) indicates the laser displacement for detecting the displacement of the spherical body 4. (2) is the output waveform of the laser displacement meter 28 for detecting the displacement of the pressurized body 6, and (3) is the concrete 2
9 shows an output waveform (acceleration amplitude waveform) of the vibration sensor 24 for detecting the vibration in the pressure sensor 9, and (4) shows an output waveform (acceleration amplitude waveform) of the vibration sensor 25 for detecting the vibration of the pressurizing body 6. Hereinafter, (1) is a spherical body displacement waveform, (2) is a pressurized body displacement waveform, (3) is a concrete acceleration amplitude waveform, and (4).
Is called a pressure body acceleration amplitude waveform.

FIG. 8 shows a case where the water / cement ratio is 38% as a representative. In addition, since four waveforms having different units are shown on the same time axis (horizontal axis), no scale is attached to the vertical axis, and the standard of the size of each waveform is added as a legend on the left side of the vertical axis. is there.

As can be seen from the spherical body displacement waveform of (1), when the spherical body 4 is released into the fresh concrete 29, it once falls, and starts to rise from the time point c.
On the other hand, as can be seen from the pressing body displacement waveform of (2), the pressing body 6 rapidly descends from the time point b when it is placed on the fresh concrete 29 to almost the time point c, but thereafter slowly. It is descending. Further, as can be seen from the concrete acceleration amplitude waveform of (3), the acceleration amplitude in the concrete 29 increases sharply from the point b when the pressing body 6 is placed on the concrete 29, and attenuates around the point c. Since then, the same size has continued. On the other hand, the acceleration amplitude of the pressurized body 6 shows a random change from the time point b when the pressurized body 6 is placed on the concrete 29, as can be seen from the pressurized body acceleration amplitude waveform of (4). It ends at a stage that does not reach the time point c, and thereafter it gradually increases without much change.

Thus, the physical properties during compaction of the concrete 29 during vibration compaction can be divided into the following three stages: the initial stage, the middle stage, and the final stage. Initial stage (period from 0 to c shown on the horizontal axis in FIG. 8) Air in the concrete is released, and the pressurized body 6 (concrete upper surface) sinks rapidly, and mechanical pressure compaction is performed. This is the process that takes place. Middle stage (period from c to d) In the process of compaction being promoted by the simultaneous action of the viscosity and elasticity of concrete, the spacing between particles approaches a minimum. The sedimentation of the spherical body 4 stops once and moves to the ascending movement (floating), and the acceleration amplitude waveforms (3) and (4) also become smaller. The sedimentation of the pressurized body 6 is not rapid but continues. Final stage (period d to e) This is a liquefaction and additional pressurization process in which the viscosity of the concrete 29 is excellent and its liquefaction (properties of the viscoelastic body) proceeds. Although the spherical body 4 rises, the sedimentation speed of the pressurized body 6 is minimized.

The three stages are classified into the case of FIG. 3 (water / cement ratio 35%) where the water / cement ratio is smaller than the case of FIG. 8 (FIG. 5) (water / cement ratio 38%) and The case of FIG. 4 (water / cement ratio 36%) is clearer, and the case of FIG. 6 (water / cement ratio 40%) and FIG. 7 (water / cement ratio 42
%) Shows that the clarity is low. Further, by comparing these figures, the relationship between the water / cement ratio and the change in physical properties can be determined. In addition, comparing FIG. 6 and FIG. 7,
7 is clearer than FIG. 6, but this is due to measurement unevenness. Generally, ultra-hard concrete is water /
FIG. 7 shows that the cement ratio is 40% or less.
It shows that three-stage classification is possible even when the percentage exceeds%.

From the above experimental results, the acceleration amplitude in the concrete and the acceleration amplitude of the pressurized body 4 were quickly calmed down,
The timing of the onset of liquefaction can be estimated when the spherical body 4 that has once descended moves to the surface. Further, the completion time of compaction can be estimated from the attenuation of the sedimentation speed of the pressurizing body 6. From this, the relationship between concrete liquefaction and workability and the relationship between compaction completion and workability can be determined.

Although the onset of liquefaction can be estimated only from the behavior of the spherical body 4 as described above, if the time required for the acceleration amplitude waveform in the concrete to calm down is further taken into consideration, it is more reliable. Become. FIG. 9 shows the timing of the sedation of the acceleration amplitude waveform (3) captured by the vibration sensor 24 and the timing at which the levitation curve of the spherical body displacement waveform (1) slightly refracts (this timing is estimated as the end timing of liquefaction). The relationship is shown below. In this case, the excitation frequency of the vibrator 1 is 85 Hz, and the excitation acceleration is 1
2G, the average of the measured value when the concrete mixing time was 2 minutes and the measured value when the concrete mixing time was 17 minutes was determined, and the water / cement ratio (%) was plotted on the horizontal axis, and the time (seconds) was plotted on the vertical axis. I am taking. FIG. 10 shows the relationship between the water / cement ratio and the time until the acceleration amplitude in the concrete attenuates. In this figure, the horizontal axis represents the water / cement ratio (%), the vertical axis represents time (seconds), the excitation frequency of the vibrator 1 is fixed at 85 Hz, and the excitation acceleration is 10 G (A). , 12
(B) for G, (C) for 13G, and (D) for 14G. Also, the measured value when the concrete placing time is 2 minutes is connected by a broken line, and the measured value when the concrete mixing time is 17 minutes is connected by a solid line.

From FIG. 9 and comparison between FIG. 9 and FIG. 10, the time until the levitation curve of the spherical body displacement waveform (1) slightly refracts and the time until the acceleration amplitude in the concrete attenuates. Are in an approximate relationship. In addition, when the excitation acceleration is 13G to 14G, since the time until the concrete is liquefied is short, it is good as an actual molding condition. However, in the determination of workability, the range of the excitation acceleration of 10G to 12G is determined by the water / cement. This is convenient because the relationship between the ratio and the required time is clear. Furthermore, since the mixing time is related to the measured value, it is necessary to use the mixing time as a condition for determining workability. In order to make a more accurate determination, it is necessary to correct factors that affect the properties of concrete, such as temperature and humidity at the time of measurement.

The change in the sedimentation of the pressing body 6 is related to the progress of compaction of the concrete as described above. Therefore,
The sedimentation velocity of the pressurized body 6 is obtained by differentiating the displacement measured by the laser displacement meter 28 with time, and the value is fixed within a certain time (for example, 7 seconds) (for example, 0.1 mm or less).
It can be estimated that the compaction is completed at the point in time. Further, since the change in the acceleration amplitude in the concrete is also related to the progress of compaction of the concrete, it is possible to estimate the completion of compaction from the time until the acceleration amplitude is calmed down.

The viscosity coefficient of the concrete 29 can be obtained from the floating speed of the spherical body 4 as follows. That is, in FIG. 8, the average ascent speed of the spherical body 4 is given by, for example, the time t from the time point c to the time point e and the displacement amount h at that time t by h / t. 29 can be regarded as a relative speed with respect to 29. From the time point c to the time point e, the concrete 2
9 shows the properties of the viscoelastic body, and the sphere 4 rises vertically in the viscoelastic body. Therefore, the following equation, which holds when the sphere moves linearly in a flow having an extremely small Reynolds number, can be applied. This equation can be similarly applied to the case where the spherical body 30 is forcibly pulled up as in the example of FIG. However, in this case, the lifting speed of the spherical body 30 can be regarded as a relative speed to the concrete 29.

F = 3πμUD where F is the pulling force (N) of the sphere, and μ is the viscosity coefficient (K
N · s · m ⁻² ), U is the relative speed (m · s ⁻¹ ) between the sphere and concrete, D is the diameter (m) of the sphere, and π is the pi. F can be replaced by buoyancy acting in concrete when the spherical body 4 rises only by buoyancy as in the example of FIG. 1, and is the load by the pulling weight 31 in the example of FIG. .

FIG. 11 shows the spherical body 4 measured by the measuring apparatus shown in FIG.
2 is compared with the lifting speed of the spherical body 30 by the measuring device of FIG. Further, FIG.
Is compared with the viscosity coefficient when the spherical body 30 is pulled up. However, the size of the spherical body 4 and the buoyancy in concrete are as described above. The diameter of the spherical body 30 is 28.5 mm, and the weight of the pulling weight 31 is 1 kgf. In these figures, the broken line indicates the case where the spherical body 4 is floated, and the solid line indicates the spherical body 3
This is the case where 0 is raised. The excitation frequency of the vibrator 1 is fixed at 85 Hz, and the excitation acceleration is 10G (A), 12G (B), 13G (C), and 14G (D). ). FIG. 11 shows the water / cement ratio (%) on the horizontal axis and the speed (mm / s) on the vertical axis. FIG. 12 shows the water / cement ratio (%) on the horizontal axis and the viscosity coefficient μ (KN · s · m ⁻² ) on the vertical axis.

As can be seen from FIG. 11, the floating speed of the spherical body 4 hardly changes even when the water / cement ratio increases, but the lifting speed of the spherical body 30 increases as the water / cement ratio increases. I have. As can be seen from FIG. 12, the viscosity coefficient when the spherical body 4 is floated and the viscosity coefficient when the spherical body 30 is pulled up are almost the same at the same water / cement ratio, or are slightly different. Although there is a difference, there is no great difference, and it changes in a similar transition due to a change in the water / cement ratio. The viscosity coefficient can be measured accurately because the viscosity coefficients in the two cases are similar to each other and the change in the viscosity coefficient due to the change in the water / cement ratio clearly appears in both cases. Can be proved by collating each other.

As described above, in the example of FIG. 1, the vibration of the concrete, the vibration of the pressing body 6, and the vibration of the vibration table 2 are the same.
Two vibrations are detected, and in the example of FIG. 2, two vibrations, that is, the vibration of the pressurizing body 6 and the vibration of the vibration table 2 are detected. Therefore, if the phase difference between the three or two vibrations is taken out, the physical properties of the concrete can be grasped in more detail, and the property of the concrete can be determined from the aspect of the amplitude ratio and the phase difference.

In the above description, the concrete liquefied by vibration is exemplified by ultra-hard concrete.
Such materials include, for example, slag and sandy soil that liquefies during an earthquake, and in particular, if the present invention is applied to such sandy soil, understanding of the liquefaction phenomenon of the ground during an earthquake and its countermeasures. Can help.

[0040]

The effects of the present invention are listed below. With respect to a substance that liquefies due to vibration of ultra-hard concrete or the like, the physical properties of the substance during the vibration compaction process can be dynamically and easily measured. In addition to capturing the process of liquefaction every moment, it is possible to estimate the onset of liquefaction and dynamically capture the progress of compaction and changes in viscosity.In the case of concrete, It is possible to know the relationship between the timing of liquefaction caused by vibration compaction and workability. Since the speed is obtained from the displacement of the spherical body, it is possible to measure the viscosity coefficient and the like in the compaction process. By changing conditions such as the frequency and intensity of the applied vibration and the water / cement ratio in the case of concrete, the relationship with the conditions can be known. Detecting the displacement of the pressurized body to which the load is applied can estimate the completion time of compaction from the decay of the sedimentation velocity of the pressurized body. In addition, since a factor called displacement (settling speed) of the pressurized body is added, estimation of the timing of occurrence of liquefaction, grasp of the progress of compaction, determination of workability, and the like become more accurate and easier. When vibration is detected by a sensor attached to a sphere, vibration in the substance at the current position of the sphere suspended vertically displaceably can be directly detected, so that changes in physical properties can be accurately detected. Can be caught. It is also useful for studying concrete consistency. Both the displacement of the spherical body and the displacement of the pressurized body can be detected outside the container, and when vibration is detected by a sensor attached to the spherical body, vibration in the substance can be directly detected as described above, When vibration is detected by the sensor provided in the pressurized body, the vibration that has propagated through the substance can be detected indirectly outside, so the displacement of the spherical body, the displacement of the pressurized body, and the vibration of the substance Can be detected while the container in place of the formwork is closed with a pressurized body and closed in the same way as during the actual molding of ultra-hardened concrete, so make measurements in accordance with the actual molding process. Can be. It can be applied not only to super-hardened concrete but also to grasp the physical properties of sand liquefied during an earthquake.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a measuring apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram illustrating a measuring apparatus according to a second embodiment.

FIG. 3 is a diagram showing detection waveforms tested by the measurement device of FIG. 1 when the water / cement ratio of concrete is 35%.

FIG. 4 is a similar view when the water / cement ratio of concrete is 36%.

FIG. 5 is a diagram when the water / cement ratio is set to 38%.

FIG. 6 is a diagram when the water / cement ratio is set to 40%.

FIG. 7 is a diagram when the water / cement ratio is set to 40%.

FIG. 8 is a diagram for explaining a detected waveform as a representative when the water / cement ratio of concrete is 38%.

FIG. 9 is a graph showing the relationship between the time at which the acceleration amplitude waveform of vibration in concrete obtained from the experimental results obtained by the measurement device of FIG. 1 is calmed down, and the time at which the levitation curve of the spherical body displacement waveform slightly refracts. It is.

FIG. 10 is a graph showing the relationship between the water / cement ratio and the time until the acceleration amplitude in concrete is attenuated.

11 is a graph comparing the flying speed of a spherical body in the measuring device of FIG. 1 with the lifting speed of the spherical body in the measuring device of FIG. 2;

FIG. 12 shows a viscosity coefficient obtained from the measuring apparatus of FIG. 1 and FIG.
5 is a graph comparing the viscosity coefficient obtained from the measurement device of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vibrator 2 Vibration table 3 Container 4 Spherical body 5 Spherical body suspending mechanism 6 Pressurized body 7 Pressurized body suspending mechanism 17 Weight for adjusting load on top of load 22 Balanced weight 24, 25, 26 Vibration sensor (Acceleration Sensor) 27/28 Laser displacement meter 29 Concrete

Claims (10)

(57) [Claims] 1. A substance which is liquefied by vibration is put in a container, a suspended spherical body is embedded in the substance, and a vertical displacement of the spherical body is given while applying a load and vibration to the substance, and A method for measuring physical properties of a substance which is liquefied by vibration, wherein the method detects a vibration which has propagated in or through the substance. 2. The method according to claim 1, wherein vibration is detected by a sensor attached to the spherical body. 3. The liquefaction by vibration according to claim 2, wherein the weight of the sphere is balanced with the weight of the balance weight, and the sphere is levitated by buoyancy due to liquefaction of the substance. A method for measuring the physical properties of a substance. 4. The method for measuring physical properties of a substance which is liquefied by vibration according to claim 1, wherein the spherical body is pulled up into the substance with a constant lifting force. 5. The apparatus according to claim 1, wherein the overload is applied to the substance by a pressurizing body which is vertically displaceable with respect to the container, and the vertical displacement of the pressurizing body is detected. 5. The method for measuring the physical properties of a substance that is liquefied by vibration according to any one of items 4 to 4. 6. The method according to claim 5, wherein the vibration of the pressurizing member is detected. 7. The apparatus according to claim 1, wherein said container is vibrated by a vibrator, and excitation vibration of said vibrator is detected.
Alternatively, the method for measuring physical properties of a substance that is liquefied by vibration according to 6. 8. A container having an open upper surface for containing a substance to be liquefied by vibration, a vibrator for applying vibration to the container, and being displaceable in a direction perpendicular to the container to apply an overload to the material in the container. A pressurizing body, a spherical body having a built-in sensor for detecting vibration, a suspending mechanism for suspending the spherical body so as to be vertically displaceable while being embedded in the substance in the container, and a suspending mechanism for suspending the spherical body. The balance weight that balances the weight with the spherical body via the mechanism, and the vertical displacement of the spherical body is detected indirectly outside the container by detecting the vertical displacement of the balance weight or the suspension mechanism. And a second displacement sensor for detecting a vertical displacement of the pressure body. 9. The apparatus according to claim 8, further comprising a sensor for detecting a vibration of the pressurizing body. 10. A container having an open upper surface for containing a substance to be liquefied by vibration, a vibrator for applying vibration to the container,
A pressurizing body that is vertically displaceable with respect to the container in order to apply an overload to the material in the container, a spherical body, and a vertical body with the spherical body embedded in the material in the container. A suspending mechanism for suspending the movable body, a lifting weight for applying a constant lifting force to the spherical body via the suspending mechanism, and detecting a vertical displacement of the lifting weight or the hanging mechanism. A first displacement sensor for indirectly detecting the vertical displacement of the spherical body outside the container, a second displacement sensor for detecting the vertical displacement of the pressure body,
A physical property measuring device for a substance which is liquefied by vibration, comprising a sensor for detecting vibration of the pressurizing body.