JP4451937B2 - Concrete manufacturing method and weighing machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a concrete manufacturing method and a weighing machine, and more particularly to a concrete manufacturing method and a weighing machine that accurately measure a predetermined amount of aggregate and water.
[0002]
[Prior art]
Concrete uses aggregates (including fine aggregates), cement, and water (kneaded water) as main raw materials, but its characteristics vary depending on the amount of these mixed.
In particular, high-fluidity concrete has excellent self-filling properties, so it is effective for improving construction efficiency and labor saving in the field, but it is kneaded depending on the mixing ratio of the main raw materials, especially the amount of kneading water to be kneaded. Properties, that is, fluidity, are greatly affected. That is, in order to fully exhibit the characteristics of the high fluidity concrete, it is necessary to mix the main raw material according to a predetermined amount.
[0003]
Generally, aggregate has surface water on the surface.
Conventionally, for example, in a concrete manufacturing factory, the amount of kneading water has been determined by correcting the amount of surface water according to the following procedure.
[0004]
That is, the amount of aggregate containing surface water is measured.
In addition, the ratio of surface water in the aggregate is separately weighed by performing tests in accordance with sensors and standards.
Next, the amount of surface water in the aggregate is calculated from the ratio of the measured aggregate and the surface water in the measured aggregate. The amount of surface water is subtracted from the predetermined amount of kneading water to calculate the amount of water newly added from the outside.
[0005]
[Problems to be solved by the invention]
However, since the ratio of surface water in the aggregate varies depending on weather conditions such as rainfall and solar radiation and storage methods, it has always been difficult to accurately grasp the ratio of surface water in the aggregate.
For this reason, the quality of concrete may vary. In addition, the possibility of variation was particularly great in high-fluidity concrete.
[0006]
In view of the above circumstances, the present invention makes it possible to ignore the amount of surface water in the aggregate in the measurement process, the mixing amount of the main raw material does not vary, and therefore the quality of the produced concrete does not vary. It aims at providing the manufacturing method of concrete.
It is another object of the present invention to provide a weighing instrument that accurately measures the amount of aggregate and the amount of kneaded water by accurately correcting the amount of surface water in the aggregate.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the invention of claim 1
In a concrete manufacturing method including a step of measuring a predetermined amount of aggregate and a step of measuring a predetermined amount of kneaded water to be kneaded with cement, the kneading is performed when the amount of surface water in the aggregate is unknown. Water and the aggregate whose dry specific gravity ρ _S is known in advance are combined and treated as a mixture, and the volume or weight of the mixture is set to the amount when the aggregate and the kneaded water are combined in a predetermined amount. Matching the specific gravity of the mixture with a specific gravity of a mixture obtained by combining a predetermined amount of the kneaded water sufficient to completely submerge the aggregate and the aggregate. Thus, a predetermined amount of the aggregate and the kneaded water are each weighed out.
[0008]
Here, the aggregate includes fine aggregate.
[0009]
In the first aspect of the present invention, the absolute dry specific gravity of the aggregate is known in advance. The specific gravity of water is 1. For this reason, when a predetermined amount of the aggregate and a predetermined amount of the kneaded water are considered as a mixture, if one of the specific gravity, volume and weight is determined, the remaining one is also determined.
Therefore, according to the first aspect of the present invention, the aggregate and the kneaded water (including surface water) are treated as a mixture, and the specific gravity of the mixture is sufficient to completely submerge the aggregate and the aggregate. Since a specific amount of the kneaded water is matched to the specific gravity of the mixture obtained by combining each of the predetermined amounts, and the volume or weight is matched to the predetermined amount when the aggregate and the kneaded water are respectively combined by a predetermined amount, It is not necessary to measure the water to be added and the surface water separately, and the aggregate and the kneaded water can be accurately measured.
That is, the mixing amount of the main raw material does not vary, and thus the quality of the produced concrete does not vary.
[0010]
Invention of Claim 2 is the manufacturing method of the concrete of Claim 1,
A step of inserting a sufficient amount of kneaded water to completely submerge the aggregate inserted in a predetermined amount into the container, and inserting the aggregate having the absolute dry specific gravity ρ _S into the container, The volume V _S = (W−V) / (ρ _S −1) of the aggregate inside the container, calculated from the weight W and the volume V of the mixture including the kneaded water and the aggregate in the container, A step of matching a predetermined volume as a predetermined amount of aggregate, and adjusting an amount of kneading water in the container to match a weight of the mixture in the container with a predetermined weight as the predetermined amount, And a step of making the specific gravity of the mixture coincide with the specific gravity of the mixture obtained by combining a predetermined amount of the aggregate and the kneaded water.
[0011]
In the second aspect of the present invention, after inserting the aggregate into the container into which kneaded water has been inserted in advance, the weight W and the volume V are measured using the aggregate and the kneaded water as a mixture. Subsequently, the aggregate is measured by matching the volume V _S = (W−V) / (ρ _S −1) of the aggregate inside the container with the predetermined volume of the aggregate, and then in the container By adjusting the amount of water to make the weight W coincide with the predetermined weight, the specific gravity of the mixture is made to coincide with the specific gravity of the mixture obtained by combining the aggregate and the kneaded water by a predetermined amount.
Therefore, according to the second aspect of the present invention, an operation equivalent to that of the first aspect of the present invention can be obtained by performing a simpler operation.
[0012]
Invention of Claim 3 is a weighing machine used for the manufacturing method of the concrete of Claim 1 or 2, Comprising:
A container having an insertion port for inserting aggregate and water therein, a drainage port for discharging water inside, a volume measuring means for measuring the volume of the aggregate and water inside the container as a mixture, and the inside of the container And a weight weighing means for weighing the aggregate and water as a mixture.
[0013]
Here, the container is made of, for example, a stainless steel plate. The volume measuring means is a scale provided in the container, a transparent thin pipe having a scale and connected to the inside of the container, or a water level gauge that is usually used. The weight weighing means may be a load cell that is normally used.
[0014]
According to the third aspect of the present invention, the volume of the aggregate and water inside the container is measured as a mixture by the volume measuring means, and the weight of the aggregate and water in the container is determined by the weight measuring means as a mixture. As weighed. Moreover, since it has the drain outlet which discharges water, the amount of water inside a container can be reduced. Therefore, the weighing instrument used in the invention of claim 1 or claim 2 can be produced.
[0015]
The invention according to claim 4 is the weighing instrument according to claim 3,
By using the volume V of the volume measuring means, the weight W of the weight measuring means, and the absolute dry specific gravity ρ _S of the aggregate, the aggregate volume V _S = (W−V) / (ρ _S −1) inside the container. It has the calculating means which calculates.
[0016]
Here, the calculation means stores, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), an input device such as a keyboard, and an absolute dry specific gravity ρ _{S of the} aggregate inputted from the input device. And a random access memory (RAM).
[0017]
According to the invention described in claim 4, in addition to obtaining the same operation as that of the invention described in claim 3, the aggregate volume V _S = (W−V) / (ρ _S −1 inside the container is obtained by the calculating means. ) Is calculated, it is possible to produce a weighing instrument that can more easily perform the invention of claim 2.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
The main points of the present invention will be described below with reference to FIGS. 1 and 2, and then embodiments will be described with reference to FIGS. 3 and 4.
[0019]
First, the main points of the present invention will be described.
Conventionally, since the mixing amount of the kneading water and the mixing amount of the aggregate are measured by their respective weights or volumes, fluctuations in the amount of the surface water cannot be accurately corrected.
Here, the present inventor changed the viewpoint from the conventional case, and when using an aggregate with a known specific gravity, the specific gravity when the kneaded water and the aggregate are mixed, and the weight or volume. It was found that the mixing amount of the kneading water and the mixing amount of the aggregate can be accurately controlled by measuring without depending on the amount of the surface water.
Hereinafter, it will be described in detail with reference to FIG. 1 and FIG.
[0020]
FIG. 1A is a schematic diagram showing the relationship between the components of the kneaded water 2 and the aggregate 3, and FIG. 2 is a chart showing the amount of the kneaded water 2 and the amount of the aggregate 3.
As shown in FIG. 1A, the weight and specific gravity of the aggregate 3 are W _S (volume is V _S ) and ρ _S , respectively, and the weight of the surface water 2b is ΔW _l (volume is ΔV _l ). Further, the weight of the measured water 2a added from the outside is defined as W _l (volume is V _l ). That is, the weight of the kneading water 2 is an amount obtained by adding the weight of the metering water 2a and the weight of the surface water 2b, that is, W ₁ + ΔW ₁ .
[0021]
Here, as shown in FIG. 1 (B), when the measured water 2a and the aggregate 3 (including the surface water 2b) are handled as the mixture 4 using a container, for example, as shown in the chart of FIG. The weight of 4 is W = W _S + ΔW ₁ + W ₁ and the volume is V = V _S + ΔV ₁ + V ₁ . That is, the specific gravity ρ of the mixture 4 is as shown in the following equation (1).
[0022]
ρ = W / V = (W _S + ΔW ₁ + W ₁ ) / (V _S + ΔV ₁ + V ₁ ) (1)
[0023]
Next, the specific gravity ρ is matched with a predetermined specific gravity ρ ₀ expressed by the following equation (2).
[0024]
ρ ₀ = W ₀ / V ₀ = (W ₁₀ + W _S0 ) / (V ₁₀ + V _S0 ) (2)
[0025]
Here, W ₁₀ = predetermined weight of kneading water 2, V ₁₀ = predetermined volume of kneading water 2, W _S0 = predetermined weight of aggregate 3 and V _S0 = predetermined volume of aggregate 3.
That is, the following expression (3) is established.
[0026]
(W ₁₀ + W _S0 ) / (V ₁₀ + V _S0 ) = (W _S + ΔW ₁ + W ₁ ) / (V _S + ΔV ₁ + V ₁ ) (3)
[0027]
Further, the following expression (4) or (5) is established.
[0028]
(W _l0 + W _S0 ) = (W _S + ΔW _l + W _l ) (4)
[0029]
(V ₁₀ + V _S0 ) = (V _S + ΔV ₁ + V ₁ ) (5)
[0030]
From the equation (4) or (5), the relationship of weight = volume × specific gravity, and the specific gravity of water = 1, the following equation (6) can be derived.
[0031]
V _l0 = ΔV _l + V _l (6)
[0032]
Furthermore, the following equation (7) can be derived from the equations (6) and (3).
[0033]
V _S0 = V _S (7)
[0034]
That is, the specific gravity of the mixture 4 is made to coincide with the predetermined specific gravity ρ ₀ , the weight of the mixture 4 is made to coincide with the sum of the predetermined weight of the kneading water 2 and the predetermined weight of the aggregate 3, or the volume of the mixture 4 is made to be the kneading water 2 Thus, the kneaded water 2 and the aggregate 3 are mixed according to a predetermined amount regardless of the amount of the surface water 2b.
It can also be said that the above-described method is a method of utilizing the fact that the substance adhering to the surface of the aggregate 3 is water which is one of the main raw materials.
[0035]
Furthermore, the present applicant has found a practical equation shown in the following equation (9), focusing on the fact that the specific gravity of water is 1.
[0036]
(W−V) = (W ₁ −V ₁ ) + (ΔW ₁ −ΔV ₁ ) + (ρ _S −1) × V _S (8)
Deformed,
[0037]
V _S = (W−V) / (ρ _S −1) (9)
[0038]
That is, the right side of the formula (9) is made to coincide with the predetermined volume of the aggregate 3, and then the amount of the metering water 2a is adjusted to make the volume or weight of the mixture 4 coincide with the sum of the predetermined volume or the sum of the predetermined weight. By doing so, the kneaded water 2 and the aggregate 3 are mixed according to a predetermined amount regardless of the amount of the surface water 2b.
[0039]
<Embodiment example>
Hereinafter, with reference to FIG. 3 and FIG. 4, a method for producing concrete according to an embodiment of the present invention, including a step of mixing the kneaded water 2 and the aggregate 3 according to a predetermined amount using the formula (9). Will be described in detail.
FIG. 3 is a cross-sectional view showing the configuration of the weighing instrument 1 used for mixing the kneaded water 2 and the aggregate 3 according to the formula (9) according to a predetermined amount.
FIG. 4 is a diagram showing a process of using the weighing instrument 1 in the concrete manufacturing method using the weighing instrument 1.
[0040]
First, the configuration of the weighing instrument 1 will be described with reference to FIG.
As shown in FIG. 3, the weighing instrument 1 includes a container 10, a support frame 11 that supports the container 10, and load cells 11 a and 11 a (which support the support frame 11 and measure the weight W of the inserted object of the container 10. Weight measuring means), a volume measuring pipe 12 connected to the inside of the container 10 and measuring the volume V of the insert of the container 10 (volume measuring means), the measurement results of the load cells 11a and 11a, and the volume measuring pipe 12 And a calculation means 13 for calculating the amount of the aggregate 3 in the weighing instrument 1 from the measurement results.
[0041]
The container 10 is made of, for example, a stainless steel plate, and has a shape obtained by rounding the lower end of a cylinder having a semicircular cross section.
Moreover, the upper part of the container 10 is open | released in order to receive the measurement water 2a and the aggregate 3. FIG. Moreover, the lower end of the container 10 is provided with a discharge port 10a for discharging the insert, a lid 10b for covering the discharge port 10a, and an openable / closable drain port 10c for discharging the water inside.
Here, since the shape of the lower end of the container 10 is a 1/4 sphere, the lid 10b moves smoothly around one horizontal line on one side surface of the container 10 to open and close the discharge port 10a.
[0042]
The support frame 11 is made of steel, for example, and is fixed to the upper part of the container 10 by a method such as welding or bolting.
The load cells 11a and 11a are load cells used in ordinary weighing machines, and the specifications thereof are appropriately changed according to the capacity of the container 10. Further, the weight W, which is the detected value of the load cells 11a, 11a, is output to the calculation means 13.
[0043]
The volume measuring pipe 12 is a stainless steel pipe that is sufficiently thin as compared with the capacity of the container 10, and is connected to the inside of the container 10, for example, near the middle of the container 10. Further, the shape is assumed to extend horizontally from the connecting portion with the container 10 and then vertically upward. In the vertically extended portion, a scale for volume measurement is provided at regular intervals.
The volume measuring pipe 12 has a scale reading device (not shown) that reads a scale coinciding with the upper surface of the insert and outputs the value to the calculation means 13.
[0044]
For this reason, for example, when a certain amount or more of water is inserted into the container 10, the water also enters the volumetric pipe 12. Here, the height of the water surface of the volume measuring pipe 12 matches the height of the water surface of the container 10, and the volume measuring pipe 12 is formed by a sufficiently thin pipe as compared with the capacity of the container 10. By reading the scale corresponding to the water surface of the pipe 12, the amount of water in the container 10 is measured without affecting the measurement result, and the volume V is output to the calculation means 13.
[0045]
The calculation means 13 includes, for example, a CPU, a ROM, an input device such as a keyboard, a RAM that stores the specific gravity ρ _{S of the} aggregate 3 input from the input device, and a display device such as an LCD (Liquid Crystal Display). , Schematically. The CPU calculates the volume of the aggregate 3 inserted into the container 10 by the equation (9) according to the arithmetic program stored in the ROM, and the aggregate 3 according to the control program stored in the ROM. The volume calculation result and the weights W and V are displayed on the display device.
[0046]
Next, a concrete manufacturing method using the weighing instrument 1 will be described with reference to FIG. In FIG. 4, the calculation means 13 is not shown.
Concrete production methods can be broadly divided into a process for measuring the main raw material, a process for kneading the measured main raw material to make ready-mixed concrete, and a process for placing ready-mixed concrete in a formwork. Only the measurement process of the kneading water 2 and the aggregate 3 which are a part will be described in detail. In other words, the other steps are the same as the ordinary concrete manufacturing method.
[0047]
First, a predetermined amount of metered water 2a is inserted into the weighing instrument 1. Here, the insertion amount of the metering water 2a is larger than the estimated gap volume of the aggregate 3 and the predetermined amount of the kneading water 2, so that the aggregate 3 is on the water surface even if the aggregate 3 is inserted by a predetermined amount. It does not come out (FIG. 4A).
[0048]
Next, the aggregate 3 is gradually inserted into the weighing instrument 1 while stirring so that the aggregate 3 does not come out on the surface of the measured water 2a and the aggregate 3 does not get air. Here, the display value of the display unit of the calculation means 13 gradually increases.
When the display value of the display unit of the calculation means 13 becomes equal to the predetermined volume of the aggregate 3, the insertion of the aggregate 3 is terminated (FIG. 4B).
[0049]
Next, until the weight W of the load cells 11a and 11a becomes W = W ₁₀ + W _S0 , the metering water 2a of the container 10 is removed from the drain port 10c. Here, in the case of weight W <W ₁₀ + W _S0 , weighed water 2 a is added to establish weight W = W ₁₀ + W _S0 .
With the above operation, the measurement of the kneaded water 2 and the aggregate 3 is completed (FIG. 4C).
[0050]
Subsequently, the lid 10b is moved to open the discharge port 10a, the kneaded water 2 and the aggregate 3 are charged into a mixer disposed below the discharge port 10a, and a predetermined amount of cement is charged.
The subsequent steps are the same as the normal concrete manufacturing process.
[0051]
As described above, according to the concrete manufacturing method according to the embodiment of the present invention, the aggregate 3 and the metering water are inserted by inserting the aggregate 3 into the weighing instrument 1 in which a large amount of the metering water 2a is inserted in advance. integrally weighed 2a and surface water 2b as a mixture, followed after weighed aggregate 3 according (9), by establishing the weight W = W _l0 + W _S0 by adjusting the amount of gauging water 2a The kneading water 2 is weighed. That is, since the kneaded water 2 and the aggregate 3 are made into the mixture 4 and the amount and specific gravity are made to coincide with a predetermined value, the aggregate 3 and the kneaded water 2 are placed in spite of the unknown amount of the surface water 2b. Weigh out as determined.
Accordingly, the mixing amount of the main raw material does not vary, and therefore the quality of the manufactured concrete does not vary.
[0052]
In addition, there is no need to perform measurement by a sensor or a test in accordance with regulations, and it is possible to accurately measure the kneaded water 2 and the aggregate 3 only by measuring the measured water 2b and the aggregate 3 three times in total. Work is simplified while measuring accuracy is increased.
[0053]
The scale reading device for the volumetric pipe 12 may be omitted, and an operator may read the scale of the volumetric pipe 12 that coincides with the water surface and input the value to the calculation means 13. In this case, it is desirable to use glass or transparent plastic as the material of the volume measuring pipe 12 so that the scale can be confirmed from the outside.
A similar modification can be applied to the measurement results of the load cells 11a and 11a.
[0054]
Further, a scale may be directly attached to the container 10 or a water level meter may be attached without using the volume measuring pipe 12.
[0055]
【The invention's effect】
According to the first aspect of the present invention, the aggregate and the kneaded water (including surface water) are treated as a mixture, and the specific gravity of this mixture is set to the specific gravity of the mixture obtained by combining the aggregate and the kneaded water by a predetermined amount. Since the volume and the weight are matched to the predetermined amount when the aggregate and the kneaded water are respectively combined in a predetermined amount, there is no need to measure the water added from the outside and the surface water separately. And aggregate and kneading water can be measured accurately.
That is, the mixing amount of the main raw material does not vary, and thus the quality of the produced concrete does not vary.
[0056]
In the invention according to claim 2, the weight W and the volume V are measured by inserting the aggregate into the container into which the kneaded water has been inserted in advance, and using the aggregate and the kneaded water as a mixture. Subsequently, the aggregate is measured by matching the volume V _S = (W−V) / (ρ _S −1) of the aggregate inside the container with the predetermined volume of the aggregate, and then in the container By adjusting the amount of water to make the weight W coincide with the predetermined weight, the specific gravity of the mixture is made to coincide with the specific gravity of the mixture obtained by combining the aggregate and the kneaded water by a predetermined amount.
Therefore, according to the invention described in claim 2, the same effect as that of the invention described in claim 1 can be obtained by performing a simpler operation.
[0057]
According to a third aspect of the present invention, the volume and the volume of aggregate and water inside the container are measured as a mixture by the volume measuring means, and the weight of the container and the aggregate and water are measured as a mixture by the weight measuring means. Weighed. Moreover, since it has the drain outlet which discharges water, the amount of water inside a container can be reduced. Therefore, the weighing instrument used in the invention of claim 1 or claim 2 can be produced.
[0058]
According to the invention described in claim 4, in addition to obtaining the same effect as that of the invention described in claim 3, the aggregate volume V _S = (W−V) / (ρ _S −1) inside the container is obtained by the calculation means. Is calculated, so that a weighing instrument capable of more simply carrying out the invention of claim 2 can be produced.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing the relationship between components of kneaded water 2 and aggregate 3;
FIG. 2 is a chart showing the amount of kneading water 2 and the amount of aggregate 3;
FIG. 3 is a diagram of a weighing machine 1 used in a concrete manufacturing method according to an embodiment of the present invention and used to mix kneaded water 2 and aggregate 3 according to a predetermined amount using equation (9). It is sectional drawing which shows a structure.
FIG. 4 is a diagram illustrating a process of using the weighing instrument 1 in a concrete manufacturing method using the weighing instrument 1.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Weighing device 2 Kneading water 2a Metering water 2b Surface water 3 Aggregate 10 Container 10a Discharge port 10b Lid 10c Drain port 11 Support stand 11a Load cell (weight measuring means)
12 Volumetric pipe (volume measuring means)
13 Calculation means

Claims (4)

In a method for producing concrete, comprising a step of measuring a predetermined amount of aggregate and a step of measuring a predetermined amount of kneaded water to be kneaded with cement.
When the amount of surface water in the aggregate is unknown, the kneaded water and the aggregate with a known absolute dry specific gravity ρ _S are treated together as a mixture,
Matching the volume or the weight of the mixture with a predetermined amount of the aggregate and the kneaded water,
Matching the specific gravity of the mixture to a specific gravity of a mixture obtained by combining a predetermined amount of the kneaded water in an amount sufficient to completely submerge the aggregate and the aggregate ;
A concrete manufacturing method characterized by measuring a predetermined amount of the aggregate and the kneaded water. Inserting a sufficient amount of kneaded water into the container to completely submerge the aggregate inserted in a predetermined amount;
An aggregate of which the absolute specific gravity ρ _S is known is inserted into the container, and is calculated from the weight W and the volume V of the mixture of the kneaded water and the aggregate in the container. A step of matching the volume V _S = (W−V) / (ρ _S −1) of the aggregate with a predetermined volume as a predetermined amount of the aggregate;
By adjusting the amount of the kneading water in the container so that the weight of the mixture in the container matches the predetermined weight as the predetermined amount, the specific gravity of the mixture is determined for each of the aggregate and the kneading water. Matching the specific gravity of the quantitatively mixed mixture;
The method for producing concrete according to claim 1, comprising: A weigher used in the method for producing concrete according to claim 1 or 2,
A container having an insertion port for inserting the aggregate and water therein, and a drainage port for discharging the internal water;
Volume measuring means for measuring the volume of aggregate and water inside the container as a mixture;
Weight weighing means for weighing the aggregate and water inside the container as a mixture;
A weighing instrument comprising: Using the detection result V of the volume measuring means, the detection result W of the weight measuring means, and the absolute dry specific gravity ρ _S of the aggregate, the volume V _{S of the} aggregate inside the container = (W−V) / (ρ _S The weighing device according to claim 3, further comprising a calculation unit that calculates −1).

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