JPH0658312B2 - Concrete slump measurement method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a concrete slump measuring method for measuring fresh concrete slump during concrete kneading.

[Conventional technology]

Raw concrete hardening strength is greatly affected by kneading softness and slump. When concrete is kneaded, even if the same materials are mixed with the same composition, the raw concrete of the same slump is not always kneaded. This is because the water content in the aggregate greatly influences the slump, and the amount of water in the aggregate is measured in advance to determine the input amount. It is preferable to measure and correct the input water amount.

As a conventional method for measuring slump during kneading of fresh concrete, the load at the time of kneading blade drive corresponds to the slump value during kneading with a concrete mixer, and the slump measurement is performed by detecting the load during kneading. There are things that are going.

This slump value differs depending on the concrete mix type and the kneading amount. Therefore, conventionally, the slump value for the concrete mix type and the load value for each kneading amount is obtained in advance,
The load value during actual kneading was compared with the data obtained in advance to predict the slump value.

[Problems to be solved by the invention]

However, the above-mentioned conventional slump measurement method has one data for each concrete mix type and each mixing amount (each mixing condition), and when comparing the data with the actual data during mixing, if both data are different from each other. The accuracy may be poor and measurement may be impossible.

The present invention has been made to solve such a problem.

[Means for solving problems]

The present invention, in a slump measuring method of green concrete during kneading in a mixer, a plurality of actual measurements of absolute load fluctuation at the time of kneading and slump value at the time of kneading are measured in advance according to kneading conditions, and the actual measurement is performed. A conversion scale for the slump value and the absolute load at the required mixing time is created based on at least two data under the same mixing conditions, and the absolute load at the same mixing time for the fresh concrete being mixed is updated. In the concrete slump measuring method, the slump value is obtained from the newly measured and measured absolute load by using the same kneading condition of the conversion scale.

[Work]

A plurality of absolute load fluctuations at the time of kneading and slump values at the time of kneading are measured and measured according to the kneading conditions, and the slump at the required kneading time is based on at least two data of the actually measured measurement data under the same kneading conditions. Make a scale to convert the value to the absolute load. Newly measure the absolute load of the fresh concrete currently being mixed at the same mixing time as above. By comparing this newly measured and measured absolute load with that of the conversion scale under the same kneading conditions, the slump value of the green concrete being currently kneaded can be obtained. Therefore, even if the past data and the data being kneaded do not match, the slump value can be easily and accurately obtained.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

When the blending type (blending No.) and kneading both are determined (kneading conditions are determined), this kneading condition is input by the setting device (1) (2), and the past data that matches the kneading condition is stored Withdraw from the vessel (3). Regarding the same kneading conditions in the memory device (3),
Input at least two past data.

Here, the absolute load fluctuation when concrete is mixed (for example, the change in the hydraulic pressure of the hydraulic line of the hydraulic motor is measured for each of the mixing operation and the mixer idle operation, and the measured value during the mixer operation is measured from the measurement value during the mixer operation). (The value obtained by subtracting) was increased with the introduction of the material, decreased as the kneading progressed, and became almost constant as the kneading progressed. A graphical representation of this relationship is as shown in FIG. In FIG. 2, the vertical axis represents the oil pressure P, the horizontal axis represents the time T, S ₁ , S _2, ... Show the absolute load change curve of which slump is known, and S _x shows the absolute load change curve of concrete during kneading. .

Setting device for kneading condition of fresh concrete to be newly kneaded (1) (2)
2 or more past data under the same kneading conditions input to the setters (1) and (2).
Screen display device such as CRT which is taken out from (3) and read
Display in (4). In addition, the maximum and minimum of the slump values of the two or more past data that have been taken out at the required kneading time are obtained, and the absolute load values for the maximum and minimum slump values are obtained, respectively.

Then, from the magnitudes of the maximum and minimum slump values and the magnitudes of the load absolute values at that time, for example, the absolute load 1
On the other hand, it is possible to create a conversion scale (6) which is represented by the ratio of the slump value, and the conversion scale (6) is displayed on the screen display device (4).

The screen display device (4) of FIG. 1 displays a conversion scale (6) consisting of scales of the ratios obtained for the absolute load fluctuation curves S ₁ , S ₂ which are past data. By displaying the absolute load curve S _x, which is a new measurement of the absolute load during the current kneading, on the display device (4), only the scale of the conversion scale (6) is read, and the slump value of the concrete under the current kneading is read. You can know.

The conversion scale (6) may be created at any time during the kneading time, but is preferably at the kneading time when the absolute load fluctuation becomes constant as shown at the right end of the curve shown in FIG.

Furthermore, the concrete kneading conditions during kneading are temporarily stored, and the slump of the kneaded concrete is actually measured according to the prescribed method. It is input to the memory device (3) as new performance data and the known data is satisfied.

〔The invention's effect〕

As described above, according to the present invention, a slump scale for the absolute load value of concrete kneading is created based on a plurality of past data, and the slump of concrete being kneaded is measured based on the scale. The measurement range of the slump is expanded and the measurement accuracy is improved.

[Brief description of drawings]

FIG. 1 is a block diagram for explaining the present invention, and FIG. 2 is a graph showing a load fluctuation curve during kneading. (1) (2) is a setting device, (3) is a memory device, (4) is a screen display device,
(5) shows a hydraulic pressure detector, (6) shows a graph scale, and (7) shows a keyboard.

Claims (1)

[Claims] 1. In a slump measuring method of green concrete being kneaded in a mixer, a plurality of absolute load fluctuations at the time of kneading and a slump value at the time of kneading are actually measured according to the kneading conditions, and the actually measured data are obtained. Based on at least two data under the same kneading conditions, a conversion scale between the slump value and the absolute load at the required kneading time is created, and the absolute load of the fresh concrete during kneading at the same kneading time is newly added. A concrete slump measuring method, which comprises measuring and measuring, and using the same kneading conditions of the conversion scale, obtaining a slump value from a newly measured absolute load.