JP2000247719A - Production of hardened body and hardened body composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control the density of a hardened body and to enlarge applicability by formulating a hydraulic material containing cement, burned ash, a hardening accelerator and an aggregate with seawater and/or water in the range of an optimum water ratio + a specific %, placing the mixture in a frame mold to give a hydraulic material and compacting the hydraulic material by vibration. SOLUTION: A hydraulic material 3 containing cement, burned ash, a hardening accelerator and an aggregate is kneaded with seawater and/or water in the range of an optimum water ratio + (0-5)% to give a hydraulic material 3. The amount of the cement is 10-50 pts.wt. based on 100 pts.wt. of the burned ash such as coal ash. An inorganic salt such as sodium chloride is used as the hardening accelerator and its amount added is 1 to 2.5 pts.wt. based on 100 pts.wt. of the mixture of coal ash and cement. The amount of the aggregate such as metal slag is preferably 50-100 wt.%. The hydraulic material 3 is placed in a frame mold 1, vibrated by a vibrator 2 and compacted to give a hardened body. The density of the hardened body is controlled by the addition of the aggregate to give a high-density hardened body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a high-density cured product using a large amount of incinerated ash and a cured product composition.

[0002]

2. Description of the Related Art The construction of power plants has been promoted in response to the increase in demand for electric power in recent years. However, coal-fired power plants have been reviewed from the viewpoint of suppressing mass consumption of petroleum fuel. Under such circumstances, it is expected that the construction of coal-fired power plants will increase in the future, and the amount of coal ash generated will increase significantly with the increase.

[0003] Coal ash as such incinerated ash is effectively used as a raw material for cement, admixture for concrete, and the like, but at present, the ratio of landfill disposal is still high. Therefore, expanding the effective use of coal ash has become an important issue.

[0004] For this reason, the present applicant has developed a method for producing a cured product using a large amount of raw coal ash powder as one method of effective utilization of coal ash. No. 9-12348 was proposed. The hardened material using this coal ash has been mainly used for the production of marine structures, for example, blocks of artificial undersea mountains for the purpose of developing artificial fish reefs and fishing grounds.

[0005]

The density of a cured product using a large amount of coal ash is determined by the density of the coal ash and the optimum water powder ratio, and the specific gravity is approximately 1.7 to 1.9.
In the range. This value is smaller than concrete or natural aggregate, and when applied to soft ground, it is superior to settlement and burial. However, wave-dissipating blocks,
When applied to a location affected by an external force such as a wave, a high density, for example, a specific gravity of 2.2 to 2.
Since about 8 is required, its application is difficult at present.

[0006] The present invention has been made in view of the above points, and enables the control of the density of a cured body, for example, the specific gravity of about 2.2 to 2.8, and the application of the cured body can be expanded. It is intended to provide a production method and a cured product composition.

[0007]

Means for Solving the Problems In order to solve the above problems and achieve the object, the present invention has the following constitution.

[0008] The invention described in claim 1 is based on the idea that "a hydraulic material containing cement, incineration ash, a hardening accelerator and an aggregate is kneaded, and seawater and / or water is added to an optimum water content ratio of + (0 to 5)%. A method for producing a cured product, comprising adding and kneading within the range described above, kneading the mixture, placing the mixture in a mold, and vibrating the mold to compact the hydraulic material placed. ].

According to the first aspect of the present invention, the density of the hardened body can be controlled, for example, by controlling the specific gravity to 2.2 by mixing the aggregate into the cement, the incinerated ash and the hardening accelerator.
To 2.8, and a high-density cured body composition can be produced.

[0010] The invention according to claim 2 is characterized in that the cement is a variety of Portland cements such as ordinary Portland cement, early-strength Portland cement, ultra-high-strength Portland cement, and moderately heated Portland cement. 2. The method for producing a cured product according to 1. ].

According to the second aspect of the present invention, various portland cements such as ordinary portland cement, early-strength portland cement, ultra-high-strength portland cement, and moderately heated portland cement can be used as the cement.

According to a third aspect of the present invention, there is provided a method for manufacturing a cured product according to the first aspect, wherein the incinerated ash is incinerated ash such as coal ash, trash, sludge, sludge, or volcanic ash. Method. ].

According to the third aspect of the present invention, as the incinerated ash, incinerated ash such as coal ash, trash, sludge, sludge, etc.
Or you can use volcanic ash.

According to a fourth aspect of the present invention, there is provided a method for producing a cured product according to the first aspect, wherein the curing accelerator is an inorganic salt or a kneaded product of an inorganic salt. ].

According to the fourth aspect of the present invention, an inorganic salt or a kneaded product of an inorganic salt can be used as a curing accelerator.

The invention according to claim 5 is characterized in that the aggregate includes various metal slags, natural aggregates and recycled aggregates, and these aggregates are used alone or in combination. The method for producing a cured product according to claim 1, wherein the amount is 50 to 100% with respect to a corresponding amount. ].

According to the fifth aspect of the present invention, the aggregate includes various metal slags, natural aggregates and recycled aggregates, and these aggregates can be used alone or in combination. Is 50 to 10 for the amount corresponding to the performance rate.
0% is uniform in quality and can be sufficiently compacted.

According to a sixth aspect of the present invention, there is provided the method for producing a cured body according to the first aspect, wherein the compaction is performed by using a vibration means and having a vibration acceleration of 3 g or more. ].

According to the sixth aspect of the invention, the compaction can be sufficiently compacted by using the vibration means and setting the vibration acceleration to 3 g or more.

[0020] The invention according to claim 7 is that "a hydraulic material containing cement, incineration ash, a hardening accelerator and an aggregate is kneaded, and seawater and / or water is added to an optimum water content ratio of + (0 to 5)%. A cured product composition which is added and kneaded in the range of and kneaded and vibrated to compact. ].

According to the invention of claim 7, aggregate is mixed with cement, incinerated ash and hardening accelerator, seawater and / or water are added, kneaded and compacted. Is a high-density cured body composition of about 2.2 to 2.8, so that stability can be ensured even when applied to a location that is affected by an external force such as a wave, such as a wave-dissipating block. .

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of a method for producing a cured product and a cured product composition according to the present invention will be described in detail.

In the present invention, as shown in FIG. 1, a hydraulic material containing cement, incineration ash, a hardening accelerator and an aggregate is kneaded, and seawater and / or water are added to an optimum water content ratio of + (0 to 5). %
Is added and kneaded in the range, and the mixture is poured into the mold 1 and the mold 1 is vibrated by the vibrator 2 to compact the hydraulic material 3 placed.

Examples of the cement that can be used in the present invention include various portland cements such as ordinary portland cement, early-strength portland cement, ultra-high-strength portland cement, and moderately heated portland cement; alumina cements such as alumina cement and lime alumina cement; blast furnace slag Mixed cement, pozzolan mixed cement,
Various mixed cements such as fly ash cement can be exemplified.

Of these, Portland cement, particularly ordinary Portland cement, is generally and preferably used.

Examples of the incinerated ash include incinerated ash such as coal ash, garbage, sludge, and sludge, and volcanic ash. In particular, coal ash is preferable. Examples thereof include so-called EP ash collected by an electric dust collector or pre-formed ash obtained by coarsening the so-called EP ash. Among them, EP ash is preferable because the optimum water content is constant and the handling is easy.

In the present invention, the cement is incinerated with ash 10
3 to 150 parts by weight, preferably 10 to 100 parts by weight,
Add 50 parts by weight. If the amount of cement added is less than 3 parts by weight, no strength is exhibited, and even if added over 150 parts by weight, not only does the strength not significantly increase, but also problems such as cracking occur.

Examples of the curing accelerator that can be used in the present invention include inorganic salts. Examples of the inorganic salts include alkali metal halides such as sodium chloride, sodium bromide, potassium chloride, and potassium fluoride; alkaline earth metal halides such as calcium chloride, magnesium chloride, and magnesium bromide; Can be mentioned. These inorganic salts can be used as an admixture in the form of a powder or an aqueous solution. In the latter case, the concentration is not particularly critical, but usually 1 to 20% by weight.
Used as an aqueous solution. If seawater is added and kneaded, an inorganic salt can be contained. The addition amount of the inorganic salts is 0.1% with respect to 100 parts by weight of the kneaded material of coal ash and cement.
To 5 parts by weight (dry basis), preferably 1 to 2.5 parts by weight (dry basis). If the added amount is less than 0.1 part by weight, no strength is exhibited, while if it exceeds 5 parts by weight, no increase in strength is observed even if the added amount is increased. For the kneaded material of coal ash and cement, when inorganic salts are added in the above range, the strength, particularly the compressive strength, increases remarkably, and not only the strength after short-term aging, but also the strength after long-term aging significantly increases. .

The aggregates usable in the present invention include various metal slags (blast furnace slag, electric furnace slag, copper slag, etc.), natural aggregates (river sand, crushed stone), and recycled aggregates (cocrete glass). Less is preferred. These aggregates can be used alone or in combination. The mixing ratio is 50 to 10 with respect to the amount corresponding to the actual ratio.
0% is appropriate.

The amount of the aggregate to be mixed is determined according to the target density of the cured body. If the amount is small, the quality becomes non-uniform due to the sedimentation of the aggregate. Hardening becomes difficult, so about 60-90% is more desirable.

Next, the hydraulic material is kneaded, and seawater and / or water are added within the range of (optimum water content ratio +0) to (optimum water content ratio +5)% and kneaded. The optimum water content refers to the water content at which the maximum dry density is obtained by changing the water content and compacting the test specimens at each water content and measuring the dry density. If a water content ratio exceeding (optimal water content ratio +5)% is used, the pleating is increased, and cracks may occur during drying, or moisture may remain in the cured product to cause a re-hair crack.
On the other hand, if the water content is less than (optimal water content + 0)%, compaction is extremely difficult, and the workability is deteriorated, so that casting is difficult, and sufficient strength may not be exhibited. For kneading, it is preferable to use a device such as a forced kneading mixer for kneading general ready-mixed concrete, a twin-screw forced kneading mixer, a forced continuous kneading mixer for a low water content ratio, etc., since sufficient kneading is performed.

After the hydraulic material is sufficiently kneaded, it is poured into a mold and the kneaded material is compacted by vibrating the mold. The degree of compaction of the kneaded material may be determined for a predetermined time or visually. In the case of visual observation, a situation in which the property changes from a humid powder to a fluid is observed. In addition, ± electrodes separated by a predetermined length in the mold are arranged in the mold, and while measuring the electric resistance between the electrodes obtained by energizing each electrode, the absolute value of the electric resistance is not considered. Instead, the kneaded material may be compacted by vibrating the form until the electric resistance value decreases in the tendency of the respective kneaded material itself to change over time.

Here, for the vibration, for example, a vibration means such as a hydraulic table vibrator or a vibration pile hammer can be used. Although it is desirable that the vibration acceleration is 3 g or more for compacting sufficiently, compacting is possible by selecting an appropriate water powder ratio according to the vibration conditions.

In order to enhance the strength by removing the mold after compaction, the block of the cured composition may be steam-cured at about 60 ° C.

According to the present invention, the density of the cured product can be controlled by mixing the aggregate with the cement, the incinerated ash and the curing accelerator, and a high-density cured product composition can be produced. In addition, aggregate is mixed with cement, incinerated ash, and a hardening accelerator, and seawater and / or water is added, kneaded and compacted. Since it is a high-density hardened body composition, a wave-dissipating block, etc. In addition, stability can be ensured even when the present invention is applied to a location affected by external force such as waves. Embodiment An embodiment of the present invention will be described below.

A compaction test, density and compressive strength were measured using ordinary Portland cement, coal ash, aggregates such as crushed stone, copper slag and ferronickel slag, and a hardening accelerator. Test overview <Materials used> Table 1 shows a list of materials used. In the aggregate,
General natural aggregate (hereinafter referred to as coarse aggregate) used for concrete and two types of slag were used.

[0037]

[Table 1]

<Method of kneading> (1) Compaction test Using a mortar mixer forced kneading mixer having a capacity of 51, kneading is performed for 30 seconds at low speed and 150 seconds at high speed, for a total of 180 seconds.

(2) Physical property test after curing Using a pan-type forced kneading mixer having a capacity of 201, the mixture is kneaded for a total of 180 seconds. Here, the curing accelerator is kneaded and dissolved in water in advance. <Test Items and Test Method> (1) Aggregate Quality Test The tests shown in Table 2 were performed to confirm the quality of the selected two types of slag aggregate.

[0040]

[Table 2]

(2) Compaction test A formwork (inner diameter 100 mm, volume 1,000 ml) used in JIS A1201-1979 (test method for compaction of soil by compaction) is fixed to a shaking table of a large VC testing device. Then, after compacting by vibration and smoothing the surface, the mass is measured.

The sample is put into a mold in one layer. In addition, the situation in which the property changes from a humid powder to a fluid is visually observed, and the time from the start of vibration to the fluidization is measured.

(3) Physical property test after curing The mold (φ10 × 20 cm) is fixed to a shaking table for a large VC test, and compaction is performed under predetermined vibration conditions. Curing conditions are standard underwater curing. Table 3 shows the test items and test methods.

[0044]

[Table 3]

The physical test results of the aggregate and the slag used in Table 4 are shown in FIG.
FIG. 3 shows the particle size distribution.

[0046]

[Table 4]

Test of Influence of Aggregate Mixing on Optimal Moisture Content <Experimental Factors and Levels> Table 5 shows experimental factors and levels.
Here, it is assumed that the aggregate amount corresponding to the actual rate is 100%, and the aggregate mixing ratio is set as a ratio to the aggregate amount. The vibration conditions were a vibration frequency of 66.7 Hz, an amplitude of 1 mm (both amplitudes),
A compaction test was performed under the conditions of a vibration time of 5 minutes, while changing the amount of aggregate mixed and the water powder ratio.

[0048]

[Table 5]

<Test Method> The water powder ratio was changed and compaction was performed by the above-described method. The relationship between the water powder ratio and the dry density was determined, and the water powder ratio at which the dry density became the maximum was measured. <Test Combinations> Table 6 shows the test combinations.
Here, a coarse aggregate and a copper slab were selected in consideration of the particle size and the particle size, and a test was performed in a case where they were combined.
The amount of aggregate mixed in this case is selected from the test results of single use.

[0050]

[Table 6]

<Test Results> FIGS. 4 to 7 show compaction curves (relation between water powder ratio and dry density) when coarse aggregate and slag are mixed. Here, the dry density of the paste portion excluding the aggregate and the slag was calculated from the indicated mixture in order to compare with the case where the aggregate was not mixed. From these compaction curves, the optimum water content and the maximum dry density were determined.

FIG. 8 shows the relationship between the amount of aggregate and slag mixed and the optimum water content, FIG. 9 shows the relationship between the amount of aggregate and slag mixed and the maximum dry density, and FIG. 10 shows the relationship between the amount of slag mixed and the cured body density. Show.

As the amount of aggregate and slag mixed increases, the optimum water content increases, and the maximum dry density also decreases. The difference between the increase in the optimum water content and the decrease in the maximum dry density with the increase in the mixing amount differs depending on the type of aggregate and slag mixed. The ratio is the largest for ferronickel slag having the smallest particle size, and is smaller for copper slag and crushed stone in this order. For copper slag and crushed stone, a large change is not seen when the mixing amount is 80%, and a change tends to be large when the mixing amount is 100%. When crushed stones and slags having different particle diameters are mixed, the mixing amount at which the optimum water content and the maximum dry density change slightly increases, and this is because mixing with different particle diameters increases the performance rate.

Thus, ferronickel slag having a small particle size has a large increase in the optimum water content and a large reduction ratio in the maximum dry density, and is not suitable as an aggregate to be mixed. In addition, when copper slag and crushed stone are used alone, if the mixing amount is about 80% or less, there is no significant change in the optimum water content and the maximum dry density, and good compaction is possible. Further, by mixing aggregates and slags having different particle diameters, the amount of mixable aggregate can be increased. Further, by mixing slag having a high specific gravity, the specific gravity of the carbonized ash cured product can be increased to about 2.6. Effect of Aggregate Content and Vibration Conditions on Compressive Strength <Experimental Factors and Levels> Table 7 shows experimental factors and levels.

[0055]

[Table 7]

<Test Combinations> Table 8 shows the combinations of the tests.

[0057]

[Table 8]

<Test Results> Table 9 shows the test formulations, and Table 10 shows a list of test results. 11 and 12 show the relationship between the amount of slag and aggregate mixed and the compressive strength. 13 and 14 show the relationship between the cement addition ratio and the compressive strength. FIG. 15 shows the relationship between the amount of slag and aggregate mixed and the unit volume mass.

As shown in FIG. 11 and FIG.
The compressive strength decreases linearly as the amount of aggregate mixed increases. The reduction ratio increases in the order of crushed stone, crushed stone + copper slag, and copper slag. The reduction in compressive strength due to the mixing of the aggregate is due to the change in the fracture properties due to the mixing of the aggregate. That is,
In a hardened body in which aggregate is mixed, when a compressive force acts, a tensile stress is generated around the aggregate, and the adhesive crack is developed. Therefore, by mixing the aggregate, the stress-strain relationship is changed, and the maximum stress (compression strength) at the time of fracture is reduced.
In general concrete, it is said that the larger the maximum dimension of the aggregate is, the larger the reduction ratio is, but according to the test results,
The rate of reduction is greater for copper slag with a finer grain size. This is because the surface of the copper slag is vitreous and has a lower adhesive strength than the coarse aggregate. As shown in FIG. 15, by mixing slag and aggregate, the unit volume mass can be increased, and if the type of slag and aggregate and mixing amount are appropriately selected, a cured body having an arbitrary unit volume mass Can be manufactured. Further, the strength can be controlled by appropriately adjusting the amount of cement added in accordance with the type of slag and aggregate and the amount of mixture.

[0060]

[Table 9] Formulation of cured product

[0061]

[0062]

[Table 10] List of test results (frequency: 66.7 Hz)
(Vibration time; 5 minutes)

[0063]

[0064]

As described above, according to the first aspect of the invention, the density of the hardened material can be controlled by mixing the aggregate with the cement, the incinerated ash and the hardening accelerator, for example, by controlling the specific gravity to 2 0.2 to 2.8, and a high-density cured body composition can be produced.

According to the second aspect of the present invention, various portland cements such as ordinary portland cement, early-strength portland cement, ultra-high-strength portland cement, and moderately heated portland cement can be used as the cement.

According to the third aspect of the present invention, incinerated ash such as coal ash, trash, sludge, sludge, or volcanic ash can be used as the incinerated ash.

In the invention described in claim 4, inorganic salts or kneaded products of inorganic salts can be used as the curing accelerator.

According to the fifth aspect of the present invention, the aggregate includes various metal slags, natural aggregates, and recycled aggregates, and these aggregates can be used alone or in combination. 50 to 100% of the amount corresponding to the ratio is uniform in quality and can be sufficiently compacted.

In the invention according to claim 6, the compaction is
By using the vibration means and setting the vibration acceleration to 3 g or more, it is possible to sufficiently compact the body.

According to the invention of claim 7, aggregate is mixed with cement, incinerated ash and a hardening accelerator, and seawater and / or water are added, kneaded and compacted. Since the composition is a high-density cured body composition of about 2 to 2.8, stability can be ensured even when applied to a portion affected by external force such as a wave, such as a wave-dissipating block.

[Brief description of the drawings]

FIG. 1 is a diagram showing a method for producing a cured body.

FIG. 2 is a diagram showing a particle size distribution of crushed stone.

FIG. 3 is a diagram showing a particle size distribution of a copper slab.

FIG. 4 is a diagram showing a compaction curve in which a copper slab is mixed.

FIG. 5 is a diagram showing a compaction curve with crushed stones mixed therein.

FIG. 6 is a view showing a compaction curve in which ferronickel slab is mixed.

FIG. 7 is a diagram showing a compaction curve when a copper slab and a crushed stone slab are mixed.

FIG. 8 is a diagram showing the relationship between the amount of aggregate and slag mixed and the optimal water content.

FIG. 9 is a diagram showing the relationship between the amount of mixed slag and the density of a cured body.

FIG. 10 is a diagram showing the relationship between the amount of mixed slag and the density of a cured body.

FIG. 11 is a diagram showing the relationship between the amount of slag and aggregate mixed and the compressive strength.

FIG. 12 is a diagram showing the relationship between the amount of slag and aggregate mixed and the compressive strength.

FIG. 13 is a diagram showing a relationship between a cement addition rate and compressive strength.

FIG. 14 is a diagram showing a relationship between a cement addition rate and compressive strength.

FIG. 15 is a diagram showing the relationship between the amount of slag and aggregate mixed and the unit volume mass.

[Explanation of symbols]

 1 Formwork 2 Vibrator 3 Hydraulic material

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Nao Saito 4-33 Komachi, Naka-ku, Hiroshima City, Hiroshima Prefecture Inside Chugoku Electric Power Company (72) Inventor Tatsuo Kita 2-5-8 Kitaaoyama, Minato-ku, Tokyo Between companies Guminai (72) Inventor Kazuto Fukudome 2-5-8 Kitaaoyama, Minato-ku, Tokyo, Japan Gumi (72) Inventor Hajime Sasaki 2-5-8 Kitaaoyama, Minato-ku, Tokyo Gumauchi, F-term ( Reference) 4G012 PA04 PA07 PA26 PA27 PA29 PB04 PB08 PC04

Claims (7)

[Claims] 1. Kneading a hydraulic material containing cement, incineration ash, a hardening accelerator and an aggregate, and adding seawater and / or water within an optimum water content ratio of + (0-5)%. A method for producing a cured product, comprising: kneading, casting into a mold, and vibrating the mold to compact the cast hydraulic material. 2. The method for producing a cured product according to claim 1, wherein the cement is a variety of Portland cements such as ordinary Portland cement, early-strength Portland cement, ultra-high-strength Portland cement, and moderately heated Portland cement. . 3. The method according to claim 1, wherein the incinerated ash is incinerated ash such as coal ash, trash, sludge, sludge, or volcanic ash. 4. The method for producing a cured product according to claim 1, wherein the curing accelerator is an inorganic salt or a kneaded product of an inorganic salt. 5. The method according to claim 1, wherein the aggregate comprises various metal slags, natural aggregates,
There are recycled aggregates, and these aggregates are used alone or in combination. The mixing ratio is 5% of the amount corresponding to the actual ratio.
The method for producing a cured product according to claim 1, wherein the content is 0 to 100%. 6. The method according to claim 1, wherein the compaction is performed by using a vibration means and at a vibration acceleration of 3 g or more. 7. A hydraulic material containing cement, incineration ash, a hardening accelerator and an aggregate is kneaded, and seawater and / or water is added within an optimum water content range of + (0 to 5)%. A cured product composition which is kneaded, vibrated and compacted.