JPS5871117A - Method of preparing kneaded substance by hydraulic substance powdered body such as cement - 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 is based on patent application no.
) - To reduce the amount of breathing water and obtain a product molded product with excellent toughness when mixing mortar or fresh concrete with Portland cement or other hydraulic substance powder. We aim to provide a complete and improved method for this.

Citrus cement, represented by Portland cement, and other hydraulic substance powders are indispensable materials in today's civil engineering, construction, and other technical fields, and precast products are widely used in cast-in-place and other methods, including spraying and injection methods. It is commonly and widely adopted regardless of whether it is carried out on-site. By the way, when performing disaster construction using the hydraulic substance powder, it is necessary to prepare it as a paste, mortar, or ready-mixed concrete. The amount of water necessary to obtain the desired fluidity and moldability is first added to the powder to adjust crosstalk. Adding a large portion corresponding to at least 90% of the cement (hereinafter referred to as W/C),
In the final process of kneading, the remaining amount is added to adjust the degree of fluidity. However, with such conventional methods, when the desired molding is performed using the mixed wire, a considerable amount of breathing water is generated, and the strength of the molded product obtained is not necessarily satisfactory. It is well known in the field that there are disadvantages and disadvantages such as large variations in pleats, and in the past, this was considered an unavoidable phenomenon in products made of pigeon seed cement, etc., and a certain amount of pleating time was required. It is said that the composition should be determined and the design and construction should be carried out with a sufficient safety factor in mind.

The inventors of the present invention have spent many years conducting detailed (3) research and practical studies on adjusting various cross-contaminants and obtaining products using the above-mentioned hydraulic substance powder, and have completed these studies. We have made many proposals for improvements, but as one of the basic methods to solve the disadvantages and shortcomings of the conventional membrane technology as described above, we have proposed the following: Adding an amount of primary water adjusted to form a funicular or capillary region to the hydraulic substance powder and performing primary kneading to reduce agglomerates caused by the powder, and Later, he proposed adding the remaining secondary water necessary to form the desired water-cement ratio and performing secondary kneading to form a fluid paste.
ff Application No. 153974 (hereinafter referred to as the original invention).

The present invention has been developed through further practical studies regarding the above nuclear power plants.
In the secondary mixing after the above-mentioned primary mixing, the secondary water to be added is gradually added for at least 10 hours or more, preferably about 30 to 80% of the time of the secondary mixing process. (4) This method further improves the properties of the resulting kneaded product, further reduces the breathing water content, reduces separation from the aggregate, and improves strength. A molded product with excellent performance can be obtained.

That is, to explain the details of the present invention, the present inventors have conducted extensive research into preparing kneaded products using powdered hydraulic substances such as cement as described above, and have particularly focused on preparing these kneaded products. As a result of various changes in the method for adjusting the paste, which is the basis of the The amount of water to be added is considerably reduced and kneaded, and after this kneading operation, the remaining water required is added and the second
It has been discovered that the subsequent kneading can effectively reduce the rate of generation of breathing water in the final kneaded product and improve the strength of the molded assimilated product thereby obtained. The details of this technical relationship are as clarified in the above-mentioned discussion between the nuclear power plants.
After the first kneading with the primary water meter (10 to 40 f), the secondary kneading with 40 to 1 ( W/C
), all of them are low, especially primary water 15-35%, 2 fire water 35%
-15% and the 11.2nd kneading can reduce the pleating rate to at least one-half of that by the conventional method. However, the reason why it is possible to increase the strength of the product by reducing the pleating rate to +1t',i is generally explained by the fact that when water is added to powder of a hydraulic material such as cement and kneaded with the naked eye, Even if it cannot be confirmed, it is presumed that the formation of aggregates of fine cement powder particles is unavoidable, and moreover, in the case of the conventional method in which a large amount of water is added at one time and kneaded, Even if kneading is carried out for a long time in order to form a suitable fluidized state, the possibility of dispersion of the agglomerated aggregates of cement powder particles once formed is very small. Therefore, it is presumed that even if a considerable amount of acid root moisture exists, after the nodules have been dispersed to a certain extent, the degree of further dispersion is extremely poor and the flow simply repeats.

On the other hand, in the case of primary kneading in a funicular or capillary area where the amount of water is appropriately restricted and a slurry area close to this capillary area, there is a certain amount of space between particles in the slurry area close to the funicular or capillary area. Even if water enters in a continuous manner, air is also present in equal proportion, and either the state of funicular F1 where air exists continuously or at least a continuous aqueous phase where powder particles are interposed between the particles. This state has not yet reached a slurry state showing fluidity, and in the first crosstalk added in such a state, the crosstalk object has virtually no fluidity, so the conditions for particle aggregation due to acid radical hydration are as follows. Even if they are the same, it is recognized that the torque during the crossing operation is quite high, and that a considerable crushing effect can be obtained between the coagulated lumps (7). In the present invention, in order to increase the grinding effect of 1, the 2 to be added with respect to the secondary crosstalk is for this purpose.
Next, water is gradually added and kneaded over a considerable period of time, and by doing so, the entire mixed material is brought into a fluid state under substantially uniform conditions. Looking at the details, the state of the above-mentioned primary cross-conductor is a state in which there is virtually no fluidity, whereas the secondary cross-conductor is a state in which there is an appropriate flowability in order to be able to form it into the desired shape. It is a state of having sex.

By the way, in general, during such kneading, if there is a difference in hardness or softness in the kneaded material, static friction to stop movement on the contact surface of the particles or nodules 15, and slippage to make movement.1. V-rubbing, rolling friction, etc. can be considered, but if a part of the kneaded material has a high moisture content, that is, a part with excellent fluidity, when kneading the kneaded material as described above, the problem may occur preferentially in that part. (8) There is a tendency for mixing to occur while other parts remain as they are, and as a result, an even mixing state cannot be obtained even with occasional mixing. In particular, the point at which the mixed material becomes fluid is important, and if it is kneaded in a state where some fluidized parts have occurred, concentrated slippage occurs only in these fluidized parts. A rolling phenomenon occurs, but it hardly occurs in other parts, and when water is added at once to create a fluid mixture, this tendency becomes more apparent, and eventually It is recognized that the result is that the lumps of cement powder in the mixed material are large and there are many of them.

On the other hand, if the process of transition from a non-fluid state to a fluid state as described above (the process of gradually increasing the amount of water added) progresses gradually while adding an equalization operation by kneading, crosstalk occurs. There is no deviation in the moisture value (i.e. fluidity) between the parts of the product as a whole, and even if there is a slight error in the moisture content (9), it is easily compensated for, and in this way it is generally Moisture is evenly distributed during kneading, and the occurrence of agglomerated lumps of cement powder is reduced to a certain extent, resulting in a mixed material with uniform moisture distribution and fluidity. In the case of primary water, fluidity is generally not formed in the case of primary water, so even temporary addition has little effect. However, since secondary water is in the process of becoming fluid, it is presumed that adding it gradually will have a considerable impact. .

It is preferable that the time for gradually adding secondary water to the first pi is at least 101 times the secondary crosstalk time, and generally 6
If secondary water is added within a short time of 10% F or more during the secondary kneading for 0 seconds or more, the effects of the present invention cannot be sufficiently obtained. It goes without saying that the crosstalk may be carried out in a batch manner using a general mixer, but the present invention is also capable of carrying out multi-stage t1n'1. This method is based on the method disclosed in Patent Application No. 184124 of 1955, in which a cylindrical object is made to move under the same conditions with equal circumferential restraint conditions, and the entire area of the cylindrical object is determined by its penetration volume. The difference between the value divided by and the apparent specific gravity of the interfering material is defined as the α value, and α, 0 is the α value obtained when the penetration depth is 10α. In this measurement, R is the radius of the container containing the interfering object, r is the radius of the cylinder, t is its length, W is its width, and h is its specific depth.

However, Figures 1 to fJ4 summarize and illustrate the bonding according to Table 2 above, and although the paste is made of the same water and cement, its unit volume weight (
The volume (weight) changes as shown in Figure 1 as the secondary water addition time changes, and as shown in the figure, when the present invention is used, the amount of air mixed in is reduced, and the volume and weight of the kneaded product is quite large. Also, the cylindrical insertion amount α1° of this product is as shown in FIG. Furthermore, the cement nodules are shown in Figure 3! 711 <, and the breathing rate is as shown in Figure 4, and the secondary water is 20 to 100
It has been found that it is preferable to gradually add and knead over a period of seconds, especially around 60 seconds. In addition, considering the relationship between Figures 1 and 4 above, the breathing rate of the products with increased weight according to the present invention as shown in Figure 1 is reduced, so the volume weight of each kneaded product is compared. By measuring the breathing rate and other properties of the kneaded product,
11. , can be used as an index.

The results of measuring the compressive strength of products molded with each kneaded material as described above are shown separately in Table 3 below, and Table 5
As summarized in the figure, the one in which the secondary water was added gradually was better in any case than the one in which the secondary water was added once, especially the one in which the secondary water was added over the board for 1()0 seconds. It has the highest compressive strength.

(15) Table 5 Example 2 When kneading mortar with water-cement ratio (W, <) and sand-cement ratio (S/C) as shown in Table 6 below, primary water (Wl ) to the cement (C) and 90
The first crosstalk of seconds (after adding sand (S) to the same 9
One was kneaded for 0 seconds, then kneaded while adding secondary water (W2) for 30 seconds, and then mixed with 604γ (p S M -30-6o), and the other was mixed with secondary water (W2) for 60 seconds. 61. while adding over a period of seconds. 30 seconds of crosstalk after PR (16) (PSM-60-30)
prepared. That is, in both cases, the secondary crosstalk after adding secondary water was 90 seconds, and the total crosstalk time was 270 seconds.

Sixth Table 7 shows the results of measuring the properties and characteristics of each of the mixed mortars obtained as described above.

Table 7 (17) Furthermore, concrete molded bodies were formed using the mortars obtained by simultaneously adding each mortar and secondary water, and the compressive strength was measured at 7 days and 28 days. is as shown in the following No. 86.

Table 8 Example 3 In preparing ready-mixed concrete with the composition shown in Table 9 below, cement and primary water are first kneaded for 90 seconds, and then sand (S) and coarse aggregate ( G) was added and kneaded for the same <90 seconds, then secondary water and water reducer (cement amount Q) were added and kneaded for 30 seconds, followed by 60 seconds of mixing. (PSG-(18) 3O-60), mixed while adding secondary water and water reducing agent for 60 seconds, and mixed for 30 seconds (PSG-
60-30) were prepared and the properties of these fresh concretes were measured and the results are shown in Table 10 below.

Table 1O further shows the results of measuring the compressive strength of (19) for molded bodies made of these ready-mixed concrete and molded bodies made of the same composition with zero secondary water addition time (simultaneous addition). As shown in Table 11.

Table 11 The present invention as explained above has clarified the technical reality of crosstalk adjustment of paste, mortar or ready-mixed concrete using hydraulic material powder sound such as Tokihato Yuzu cement, Adding the primary mixing due to the primary water addition and the secondary mixing due to the secondary water addition, and gradually adding the secondary water over a period of time equal to or longer than the IO of the secondary kneading process. This further reduces the pleading rate,
In addition, it increases the strength of the product and appropriately obtains a mixed material with preferable kneading properties.1. J Nijo (
20) This is a highly effective invention.

4. Additional relations This invention was published in 1982! Regarding the additional invention of No. g153974, 1゜When adding water to a powder of a hydraulic substance such as Portland cement to obtain a kneaded product, the powder of a hydraulic substance is in a funicular or capillary state. A controlled amount of primary water is added to form a slurry zone for primary mixing to reduce agglomeration caused by the powder, and necessary to form the desired water-cement ratio after this primary mixing. The remaining part 2
Adding secondary water and performing secondary kneading is the same as the original invention, but in the present invention, the addition of secondary water is continued for a certain period of time for secondary kneading as described above. By kneading while gradually adding cement powder, a preferable kneaded state is formed, the formation of lumps in the cement powder is reduced, the precipitate water is further reduced, and a product with preferable strength can be obtained. This is related to the improvement of.

[Brief explanation of drawings]

The drawings illustrate the technical content of the present invention, and include
The figure is a graph showing changes in the unit volume and weight of the paste according to the present invention and the original invention, Figure 2 is a graph showing the relationship between the secondary water injection time and the amount of cylindrical sage, and Figure 3 is the cement. Figures 1 to 4 show the relationship between changes in the amount of baby booms, Figure 4 shows the relationship between changes in the pleating rate, and Figure 5 shows the results of measuring the compressive strength of the product. be. Patent applicant: Hajime Ito Prompt inventor: Hajime Ito
Roshi Higuchi Minami
Tsuji city propensity
Hide Kaga club member
Yasuhiro Yamamoto'Ifliil'
Ub8-'/1117 (7) Continued from page 1 0 Inventor Norio Marushima 6-19-7 Ichikawa Kata Yawata 0 Inventor Mitsuyoshi Hayayo 3-6-47 Inamuragasaki, Kamakura City 0 Inventor Sakae Tazawa - 3-4-12 Wada, Suginami-ku, Tokyo 0 Inventor Yasunori Matsuoka 1-12-60 Wakabadai, Asahi-ku, Yokohama 0 Inventor Seiji Kaneko 1688 102- Fueda, Kamakura City

Claims (1)

[Claims] 1. When adding water to a powder of a hydraulic substance such as cement to obtain a mixed substance, an amount adjusted to form a slurry region close to a funicular or capillary state is added to the powder of the hydraulic substance. Primary water is added to perform the primary kneading to reduce agglomerates caused by the powder, and after this primary mixing, the remaining secondary water necessary to form the desired water-cement ratio is added to the secondary kneading. A kneaded product made of powder of a hydraulic material such as cement, characterized in that, in the case of subsequent kneading, the secondary water is gradually added over a period of 10 times or more during the second kneading process. A adjustment method.