JPS58205714A - Method of controlling quantity of water of concrete - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling the amount of water in concrete during crosstalk.

The amount of water affects the strength of concrete, the difficulty of construction, and many other factors.

However, in actual work, it is not possible to obtain the desired concrete by adding the amount of water as designed.

The reason for this is that the moisture content of aggregates stored outdoors, especially fine aggregates (sand), constantly changes.

In particular, if the method of sand stocking or the position of sand withdrawal using Pelcon is inappropriate, the rate of change is extremely large, so it is necessary to always pay attention to the current moisture content of the sand.

For this purpose, a method of measuring the slump and adjusting the moisture content has also been adopted.

This is a method in which cement, aggregate, water, etc. are simultaneously added to a mixer, and the amount of power consumed during crosstalk is detected and a slump is displayed using an automatic calculation memory circuit. Based on this slump value, the next batch is This is a method in which the operator manually adjusts the amount of water.・Therefore, there are the following drawbacks.

<B> The amount of water is always adjusted in the next batch, and the amount of water in the concrete currently being mixed is not adjusted.

<mouth> The operator manually adjusts the slump by referring to the previous slump, and requires skill and careful operation.

On the other hand, there is a method of crossing concrete lines in two steps.

In this method, cement, fine aggregate, and water are mixed in the first mix to produce mortar, and in the next mix, coarse aggregate is added to produce concrete.

It is a known fact that when the amount of crosstalk power of the mixer is maximum during the first crosstalk, the physical properties of the concrete that is completed by adding and kneading coarse aggregate in the second crosstalk will be the best.

For this reason, changes in the moisture content of sand have a particularly large effect, making management important.

Various types of sand moisture meters and sand controllers are currently in use, but they have drawbacks such as being difficult to use and requiring time and effort to perform measurements.

The present invention has been made in view of the above points, and an object of the present invention is to provide the following water amount management method.

〈A〉 A water quantity management method that can adjust the optimum slump within a single patch. Effortless Water Quantity Control Method Next, an embodiment will be described.In the method of the present invention, concrete cross-conducting is carried out in two steps.

<A> First mixing (Figure I in '#) In the first mixing, the upper mixer (1) only inputs fine aggregate (8), Shichimen (0), and primary water (Wt). . The electric current and voltage of the motor that drives the upper mixer (1) during kneading is detected by the power consumption calculation and instruction device (3), and provides an instruction signal to the water amount calculation and instruction device (4).

For example, a commercially available digital slump indicator is used as the power consumption calculation and instruction device (3).

This is done by detecting the current and voltage of the mixed mixer, and then combining the values and the characteristic data input in advance (by composition,
This is a device that compares and calculates the slump value corresponding to the amount of power (contamination) and selects and displays the slump value corresponding to the amount of power.

By the way, as mentioned above, it is known that when the amount of power consumed during the primary mixing reaches its maximum, the physical properties of the mixed concrete will be the best.

Therefore, we set the expected maximum power consumption after several trial runs.
If this and the current power consumption of the primary kneading are not equal, (
1) The amount of secondary water (W:) in the same patch can be increased or decreased to finally obtain the optimal amount of water.

This is the adjustment of the optimal amount of water within the same patch. (ii
) It is possible to increase or decrease the amount of primary water (Wl) in the next patch to perform the primary kneading under the best conditions (with the expected maximum consumption).

This is not an adjustment within the same patch, but an instruction for the next patch.

<Exit> Secondary crosstalk (≠Figure 4 ■) The mortar discharged from the upper mixer (1) is transferred to the lower mixer (
2), into which external aggregate (G) and secondary water (W, ) are added.

By the way, as mentioned above, if the amount of water in the first kneading is too large (
If the moisture content of the sand is higher than the previous time) or too low (the sand is drier than the last time), the amount of power consumed will not be equal to the expected maximum amount of power.

Therefore, from the difference between the amount of electricity consumed during the first practice and the expected maximum amount of electricity, it is possible to determine the excess or deficiency in the amount of water, and the amount of secondary water (Wl) that should be corrected.
The amount is calculated and determined, and then put into the lower mixer (2).

As a result, the total amount of water can be adjusted, and slump can be stabilized.

Further, by detecting the power consumption of the motor (M3) of the lower stage mixer (2), it is possible to know the kneading slump.

Since the present invention is as described above, the following effects can be expected.

<B> Instead of concrete cross-conducting at once, water is added in two steps, and the appropriate amount of secondary water is calculated by comparing the power consumption during the first cross-conducting with the expected maximum power consumption. , is configured to be input.

Therefore, the amount of water can be adjusted within one patch, making it possible to obtain concrete with stable slump.

<口> Based on the amount of power consumed at the time of the first crosstalk, it is possible to calculate the amount of primary water so that the amount of power consumed in the next patch matches the expected maximum amount of power.

It is known that by maximizing the amount of electricity consumed during the first mixing, concrete with the best physical properties can be finally obtained, so in the next patch, not only should the slump be appropriate, but also various strengths should be used. It is possible to obtain concrete with excellent pumping performance, durability, rust prevention effect, etc.

[Brief explanation of drawings]

The figure is an explanatory diagram of an embodiment of the management method of the present invention, 1: upper mixer, 2: lower mixer, 3: power consumption calculation instruction device, C: cement, S: fine aggregate, G: aggregate, W: Water patent applicant Taisei Corporation

Claims (1)

[Claims] When mixing concrete, water and concrete materials are added to the mixer in two steps, and the power consumption of the mixer during the first mixing and the expected maximum consumption obtained through testing and mixing are calculated. The system is configured so that it can detect excess or deficiency in the amount of primary water in the mix by comparing it with the amount of electric power, and can adjust the amount of secondary water during the second kneading process and instruct the amount of primary water for the next batch. IJ-to water volume management method