JP4009819B2 - Concrete material measurement method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an aggregate having different surface water states and a concrete material measuring method for measuring water.
[0002]
[Prior art]
When mixing concrete on site, the amount of water has a large effect on the concrete strength, so it is necessary to manage it thoroughly during mixing. However, the moisture content of the aggregate, which is a mixing material, varies depending on its storage conditions and climatic conditions. When the wet aggregate is used, the amount of water in the concrete increases by the amount of surface water of the aggregate, and when the aggregate in the dry state is used, the amount of water in the concrete decreases by the effective water absorption.
[0003]
For this reason, it is extremely important to maintain the quality of concrete by correcting the amount of water at the time of mixing according to the degree of dryness and wetness of the aggregate and producing concrete as indicated.
[0004]
Here, the ratio of the amount of surface water in the wet state (the amount of water adhering to the surface of the aggregate) divided by the mass of the aggregate in the surface dry state (surface dry saturated state) is called the surface water ratio. However, since stored aggregates are generally often wet, it is common to measure the surface water ratio in advance as an indicator of the dryness and wetness of the aggregate, and adjust the amount of mixing water based on the measured value. Is.
[0005]
And, the measurement of the surface water ratio is conventionally performed by taking a small amount of sample from a storage container called a stock bottle in which aggregates are stored and measuring the mass and the mass in an absolutely dry state. And the water absorption rate of the surface dry state measured in advance.
[0006]
[Problems to be solved by the invention]
However, in such a measuring method, a heating operation using a burner or the like is required to measure the mass in an absolutely dry state, which causes a problem of being unrealistic in terms of economy and time.
[0007]
In addition, in order to make up for such problems, there are cases where the operator visually confirms the mixing status or adjusts the mixing water amount by referring to the load current of the mixer. The method itself has low accuracy, and eventually, a large safety factor of about 20% in terms of strength has to be expected, resulting in a problem that the composition becomes uneconomical.
[0008]
The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a concrete material measurement method capable of measuring the mass of aggregate and water efficiently and with a predetermined accuracy.
[0009]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the concrete material measuring method according to the present invention should measure and measure the mass M _wsi of water by introducing water into the first measuring tank as described in claim 1. Among the fine aggregates, a part of the fine aggregates is put into the first measuring tank so that the part of the fine aggregates becomes a water-immersed fine aggregate that does not come out of the water surface. The total mass M _fs and the total volume V _fs are measured, ρ _s is the density of the fine aggregate in the surface dry state, ρ _w is the density of water,
M _s + M _ws = M _fs (1)
M _s / ρ _s + M _ws / ρ _w = V _fs (2)
To determine the surface mass M _s of the fine aggregate and the water mass M _ws of the water in the first measuring tank, and then the M _ws and M _wsi are _expressed by the following equation:
(M _ws -M _wsi ) / M _s (3)
Substituting into the fine aggregate to calculate the surface water content of the fine aggregate, and then correct the remaining fine aggregate of the fine aggregate to be weighed with the surface water content of the fine aggregate. A fine aggregate metering step of calculating a surface water mass M _wss adhering to the remaining fine aggregate of the fine aggregates using a surface water ratio of the partial fine aggregates;
Water is poured into the second measuring tank and the mass M _wgi of the water is measured. Among the coarse aggregates to be weighed, some coarse aggregates are water from which some of the coarse aggregates do not come out of the water surface. The total mass M _fg and the total volume V _fg of the water-immersed coarse aggregate are measured in the second measuring tank so as to become the coarse aggregate, and ρ _g is measured in the dry state of the coarse aggregate. The density, ρ _w is the density of water, and the following two formulas:
M _g + M _wg = M _fg (4)
M _g / ρ _g + M _wg / ρ _w = V _fg (5)
To determine the mass M _g of the surface dry state of the part of the coarse aggregate and the mass M _wg of the water in the second measuring tank, and then the M _wg and the M _wgi are _expressed by the following equation:
(M _wg -M _wgi ) / M _g (6)
To calculate the surface water ratio of the partial coarse aggregate, and then correct the remaining coarse aggregate of the coarse aggregate to be weighed with the surface water ratio of the partial coarse aggregate. A coarse aggregate measuring step of calculating a surface water mass M _wgs attached to the remaining coarse aggregate of the coarse aggregate using a surface water ratio of the partial coarse aggregate;
By using M _ws , M _wg , M _wss and M _wgs obtained in the fine aggregate measuring step and the coarse aggregate measuring step, the remaining water M _wr of the water to be weighed is shown in a combination formula. As the amount of water M _wt , the following formula:
_{M wr = M wt - (M} ws + M wg + M wss + M wgs) (7)
It consists of the water metering process required from
[0010]
Also, weighing of the concrete material according to the present invention, the air quantity of the water immersion fine aggregate or in the water-immersed coarse aggregate as a (%), in place of the V _fs or the V _fg, V _fs -(1-a / 100) or _Vfg- (1-a / 100) is used.
[0011]
In the method for measuring a concrete material according to the present invention, first, water is introduced into the first measuring tank, and the mass M _wsi of the water is measured.
[0012]
Next, among the fine aggregates to be weighed, a part of the fine aggregates is put into the first measuring tank so that the part of the fine aggregates becomes a water-immersed fine aggregate that does not come out of the water surface. The total mass M _fs and the total volume V _fs of the water-immersed fine aggregate are measured.
[0013]
In order to measure the total mass M _fs of the water-immersed fine aggregate, for example, a load cell can be used. From the mass of the first measuring tank when filled with the water-immersed fine aggregate, the first measurement is performed. Subtract the mass of the tank only. For the total volume V _fs of the water-immersed fine aggregate, for example, a liquid level measuring means for measuring the liquid level of the water-immersed fine aggregate, specifically, an electrode type displacement sensor can be used.
[0014]
The proportion of fine aggregate to be weighed is arbitrary depending on the amount of water-immersed fine aggregate. The higher the proportion, the better the measurement accuracy for surface water. Alternatively, since it is necessary to increase the size of the apparatus such as an electrode type displacement sensor, the above-described ratio may be appropriately determined based on the balance between them.
[0015]
Next, ρ _s is the density of the fine aggregate in the surface dry state, ρ _w is the density of water,
M _s + M _ws = M _fs (1)
M _s / ρ _s + M _ws / ρ _w = V _fs (2)
_{Is obtained} to obtain a mass M _s of the surface of the fine aggregate and a mass M _ws of water in the first measuring tank.
[0016]
Next, the M _ws and the M _wsi are _expressed as follows:
(M _ws -M _wsi ) / M _s (3)
And the surface water ratio of the fine aggregate is calculated.
[0017]
Next, the remaining fine aggregate of the fine aggregate to be weighed is corrected by the surface water ratio of the partial fine aggregate and measured, and the remaining fine aggregate of the fine aggregate is The surface water mass M _wss that adheres is calculated using the surface water ratio of the fine aggregate.
[0018]
The procedure described above is similarly performed on the coarse aggregate.
[0019]
That is, first, water is poured into the second measuring tank, and the mass M _wgi of the water is measured.
[0020]
Next, among the coarse aggregate to be weighed, a part of the coarse aggregate is put into the second measuring tank so that the partial coarse aggregate becomes a submerged coarse aggregate that does not come out of the water surface. The total mass M _fg and the total volume V _fg of the water-immersed coarse aggregate are measured.
[0021]
Next, ρ _g is the density of the coarse aggregate in the surface dry state, ρ _w is the density of water,
M _g + M _wg = M _fg (4)
M _g / ρ _g + M _wg / ρ _w = V _fg (5)
_{Is obtained} to obtain the mass M _g of the surface of the part of the coarse aggregate and the mass M _wg of the water in the second measuring tank.
[0022]
Next, the M _wg and the M _wgi are _expressed as follows:
(M _wg -M _wgi ) / M _g (6)
And the surface water content of the part of the coarse aggregate is calculated.
[0023]
Next, the remaining coarse aggregate of the coarse aggregate to be weighed is measured by correcting with the surface water ratio of the partial coarse aggregate, and the remaining coarse aggregate of the coarse aggregate is measured. The surface water mass M _wgs to be attached is calculated using the surface water ratio of the partial coarse aggregate.
[0024]
If M _ws , M _wg , M _wss, and M _wgs are obtained in the fine aggregate measurement process and the coarse aggregate measurement process, the remaining water of the water to be measured is used by using these values. Assuming that M _wr is the amount of water M _wt shown in the formula,
_{M wr = M wt - (M} ws + M wg + M wss + M wgs) (7)
Ask from.
[0025]
As described above, in the present invention, the surface water of the aggregate is indirectly calculated as a part of the mass M _ws or M _wg of the water in consideration of the variation for each aggregate having different wet states. mass of the aggregate is understood as the mass M _s or M _g in the case of Table dry condition. That is, since the mass of aggregate and water will be grasped under the same conditions as the formulation, concrete can be produced with the amount of water as indicated by the formulation even if aggregates with different wet conditions are used. .
[0026]
In the present invention, fine aggregates and coarse aggregates are not necessarily measured by the water-immersed aggregate method, and thus there is a certain limit in measurement accuracy in that sense. In the case of, the surface water ratio is often treated as a constant value of about 0.5% to 1% assuming that there is no significant fluctuation, and this has been a factor that causes fluctuations in water volume, and consequently the quality of concrete. According to the present invention, it is possible to greatly improve the water amount error.
[0027]
If the air amount a (%) in the water-immersed fine aggregate or the water-immersed coarse aggregate is considered, the air amount in the water-immersed fine aggregate or the water-immersed coarse aggregate is a (%). and then, instead of the V _fs or the V _fg, by using the _{V fs · (1-a /} 100) or _{V fg · (1-a /} 100), further the actual total volume, excluding the air quantity Accurate weighing is possible.
[0028]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a concrete material measuring method according to the present invention will be described with reference to the accompanying drawings. Note that components that are substantially the same as those of the prior art are assigned the same reference numerals, and descriptions thereof are omitted.
[0029]
1 to 3 are flowcharts showing the procedure of the concrete material measuring method according to the present embodiment. As can be seen from the drawing, in the concrete material measuring method according to the present embodiment, first, water is introduced into the first measuring tank, and the mass M _wsi of the water is measured (step 101).
[0030]
For example, it is conceivable to use a measuring tank that is formed in a hollow truncated cone shape so that its inner diameter increases toward the bottom. In this way, the bottom lid can be opened without clogging the water-immersed fine aggregate or the water-immersed coarse aggregate, which will be described later, within the measurement tank without using a vibrator or other vibrator. Then, it can be naturally dropped downward and put into a kneading mixer together with separately weighed cement and the like.
[0031]
Next, among the fine aggregates to be weighed, a part of the fine aggregates is put into the first measuring tank so that the part of the fine aggregates becomes a submerged fine aggregate that does not come out of the water surface. The total mass M _fs and the total volume V _fs of the water-immersed fine aggregate are measured (step 102).
[0032]
In order to measure the total mass M _fs of the water-immersed fine aggregate, for example, a load cell can be used. From the mass of the first measuring tank when filled with the water-immersed fine aggregate, the first measurement is performed. Subtract the mass of the tank only.
[0033]
For the total volume V _fs of the water-immersed fine aggregate, for example, a liquid level measuring means for measuring the liquid level of the water-immersed fine aggregate, specifically, an electrode type displacement sensor can be used. As such an electrode-type displacement sensor, for example, the submerged fine aggregate is monitored by monitoring the change in the energized state when the lower end of the detection electrode touches the liquid level of the submerged fine aggregate accommodated in the measuring tank. What was comprised so that the liquid level of this could be measured can be used.
[0034]
The proportion of fine aggregate to be weighed is arbitrary depending on the amount of water-immersed fine aggregate. The higher the proportion, the better the measurement accuracy for surface water. Alternatively, since it is necessary to increase the size of an apparatus such as an electrode type displacement sensor, the above-described ratio may be determined as appropriate in consideration of these factors.
[0035]
Next, ρ _s is the density of the fine aggregate in the surface dry state, ρ _w is the density of water,
M _s + M _ws = M _fs (1)
M _s / ρ _s + M _ws / ρ _w = V _fs (2)
By solving the above, the mass M _s of the above-mentioned part of the fine aggregate and the mass M _ws of the water in the first measuring tank are obtained (step 103).
[0036]
Next, the first measured water masses M _wsi and M _ws are _expressed as follows:
(M _ws -M _wsi ) / M _s (3)
And the surface water ratio of some of the fine aggregates described above is calculated (step 104).
[0037]
Next, the remaining fine aggregate out of the fine aggregates to be weighed is corrected with the surface water ratio obtained in step 104 and weighed, and the mass M _wss of the surface water adhering to the remaining fine aggregate is determined. Calculation is performed using the same surface water ratio (step 105).
[0038]
The procedure described above is similarly performed on the coarse aggregate. In addition, the coarse aggregate measurement process described below is a process independent of the above-described fine aggregate measurement process, and can be performed simultaneously, or can be preceded by either.
[0039]
That is, first, water is poured into the second measuring tank and the mass M _wgi of the water is measured (step 106). The second measuring tank is the same as the first measuring tank, and the description thereof is omitted here.
[0040]
Next, among the coarse aggregate to be weighed, a part of the coarse aggregate is put into a second measuring tank so that the coarse aggregate becomes a submerged coarse aggregate that does not come out of the water surface. The total mass M _fg and the total volume V _fg of the water-immersed coarse aggregate are measured (step 107).
[0041]
Next, ρ _g is the density of the coarse aggregate in the surface dry state, ρ _w is the density of water, the following two formulas, that is,
M _g + M _wg = M _fg (4)
M _g / ρ _g + M _wg / ρ _w = V _fg (5)
By solving the above, the mass M _g of the above-mentioned part of the coarse aggregate and the mass M _wg of the water in the second measuring tank are obtained (step 108).
[0042]
Next, the first measured M _wgi and M _wg are
(M _wg -M _wgi ) / M _g (6)
And the surface water ratio of the part of coarse aggregate is calculated (step 109).
[0043]
Next, the remaining coarse aggregate of the coarse aggregate to be weighed is measured by correcting with the surface water ratio obtained in Step 109, and the surface water mass M _wgs attached to the remaining coarse aggregate is the same. Calculation is performed using the surface water ratio (step 110).
[0044]
If M _ws , M _wg , M _wss, and M _wgs are obtained in the fine aggregate measurement process and the coarse aggregate measurement process, the remaining water of the water to be measured is used by using these values. Assuming that M _wr is the amount of water M _wt shown in the formula,
_{M wr = M wt - (M} ws + M wg + M wss + M wgs) (7)
(Step 111).
[0045]
In addition, when the amount of water of the blending design contains a diluted amount of the admixture, this is excluded, and if water used for washing the blades of the kneading mixer and the lid of the measuring tank is added as a kneading material, This is also excluded.
[0046]
As described above, according to the method for measuring a concrete material according to the present embodiment, the surface water of the fine aggregate and the coarse aggregate is the mass of water in a state in which variation between aggregates having different wet states is considered. it is possible to indirectly calculated as part of the M _s or M _g, can grasp the mass of fine aggregate and coarse aggregate as a mass when the table dry condition. That is, since the mass of aggregate and water will be grasped under the same conditions as the formulation, concrete can be produced with the amount of water as indicated by the formulation even if aggregates with different wet conditions are used. .
[0047]
In the present embodiment, no particular mention was made regarding the air amount correction. However, if the air amount a (%) in the water-immersed fine aggregate or the water-immersed coarse aggregate is considered, the water-immersed fine aggregate is known. The total volume V _fs and the total volume V _fg of the water-immersed coarse aggregate may be multiplied by (1-a / 100).
[0048]
For example, instead of equation (2),
M _s / ρ _s + M _ws / ρ _w = V _fs · (1−a / 100) (2 ′)
May be used.
[0049]
With such a configuration, it is possible to measure with higher accuracy in the actual total volume excluding the air amount.
[0050]
【The invention's effect】
As described above, according to the method for measuring a concrete material according to the present invention, the surface water of the aggregate is indirectly used as a part of the mass of the water in a state where the variation between the aggregates in different wet states is considered. The mass of the aggregate can be grasped as the mass in the surface dry state. That is, since the mass of aggregate and water will be grasped under the same conditions as the formulation, concrete can be produced with the amount of water as indicated by the formulation even if aggregates with different wet conditions are used. .
[0051]
[Brief description of the drawings]
FIG. 1 is a flowchart showing a method for measuring a concrete material according to the present embodiment.
FIG. 2 is a flowchart showing a concrete material measuring method according to the embodiment.
FIG. 3 is a flowchart showing a concrete material measuring method according to the embodiment.

Claims (2)

Water is poured into the first measuring tank, and the mass M _wsi of the water is measured. Among the fine aggregates to be weighed, some of the fine aggregates are water from which some of the fine aggregates do not come out of the water surface. The total mass M _fs and the total volume V _fs of the water-immersed fine aggregate are measured so as to become the fine aggregate, and ρ _s is measured in the surface dry state of the fine aggregate. The density, ρ _w is the density of water, and the following two formulas:
M _s + M _ws = M _fs (1)
M _s / ρ _s + M _ws / ρ _w = V _fs (2)
To determine the surface mass M _s of the fine aggregate and the water mass M _ws of the water in the first measuring tank, and then the M _ws and M _wsi are _expressed by the following equation:
(M _ws -M _wsi ) / M _s (3)
Substituting into the fine aggregate to calculate the surface water content of the fine aggregate, and then correct the remaining fine aggregate of the fine aggregate to be weighed with the surface water content of the fine aggregate. A fine aggregate metering step of calculating a surface water mass M _wss adhering to the remaining fine aggregate of the fine aggregates using a surface water ratio of the partial fine aggregates;
Water is poured into the second measuring tank and the mass M _wgi of the water is measured. Among the coarse aggregates to be weighed, some coarse aggregates are water from which some of the coarse aggregates do not come out of the water surface. The total mass M _fg and the total volume V _fg of the water-immersed coarse aggregate are measured in the second measuring tank so as to become the coarse aggregate, and ρ _g is measured in the dry state of the coarse aggregate. The density, ρ _w is the density of water, and the following two formulas:
M _g + M _wg = M _fg (4)
M _g / ρ _g + M _wg / ρ _w = V _fg (5)
To determine the mass M _g of the surface dry state of the part of the coarse aggregate and the mass M _wg of the water in the second measuring tank, and then the M _wg and the M _wgi are _expressed by the following equation:
(M _wg -M _wgi ) / M _g (6)
To calculate the surface water ratio of the partial coarse aggregate, and then correct the remaining coarse aggregate of the coarse aggregate to be weighed with the surface water ratio of the partial coarse aggregate. A coarse aggregate measuring step of calculating a surface water mass M _wgs attached to the remaining coarse aggregate of the coarse aggregate using a surface water ratio of the partial coarse aggregate;
By using M _ws , M _wg , M _wss, and M _wgs obtained in the fine aggregate measurement step and the coarse aggregate measurement step, the remaining water M _wr of the water to be measured is indicated by a combination formula. As the amount of water M _wt , the following formula:
_{M wr = M wt - (M} ws + M wg + M wss + M wgs) (7)
A method for measuring a concrete material, characterized by comprising a water measuring step obtained from The amount of air in the water-immersed fine aggregate or the water-immersed coarse aggregate is a (%), and instead of V _fs or V _fg , V _fs · (1-a / 100) or V _fg · ( The method for measuring a concrete material according to claim 1, wherein 1-a / 100) is used.

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