JP2863111B2 - Lightweight multilayer solid containing latent hydraulic particles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solidified product containing tobermorite and having latent hydraulic particles, and more particularly to a lightweight multi-layered solidified product for building materials such as building panels and sound absorbing materials.

[0002]

2. Description of the Related Art Potential hydraulic particles include coal ash, blast furnace slag, silicate clay, volcanic ash, and diatomaceous earth. Here, the term “latent hydraulic property” refers to a property that does not exhibit hydraulic property by itself, but exhibits hydraulic property when a small amount of an alkaline substance such as Ca (OH) ₂ or NaOH is present. Typical latent hydraulic particles such as coal ash and blast furnace slag are described below.

[0003] In thermal power plants and various factories utilizing coal as an energy source, coal ash such as fly ash is produced in large quantities. The amount is about 4 in Japan.
At present, about 40% of the total amount reaches 100,000 tons, and only about 40% is effectively used, and the remaining about 60% is landfilled at present. However, it is not always easy to secure landfill sites for coal ash, and it is becoming increasingly difficult to secure landfill sites due to the guarantee of fishing rights and the establishment of the Recycling Law. Therefore, effective utilization of coal ash, which is expected to further increase in the future, is an urgent issue.

At present, coal ash is disclosed in
As disclosed in JP-A-17247 and JP-A-4-305044, it has been proposed as one raw material of inorganic building materials, or as disclosed in JP-A-3-16176. It has been proposed as a raw material of the agent. As a special example, as shown in the publication "Nippon Kogyo Shimbun: Constructing Artificial Seabed Mountains with Coal Ash (Issued February 26, 1993)", it has been proposed as a raw material for artificial reefs. ing.

[0005] Blast-furnace slag is a by-product obtained in the production of pig iron by mixing limestone, coke, and the like with iron ore in a blast furnace of an ironworks. The amount of slag is about 6
Considering Japan's annual production of pig iron to be 6 million tons, it means that about 4 million tons of blast furnace slag is by-produced.

There are various types of building materials, such as a PC board, an ALC board, and a sound absorbing board. Recently, various ALC boards have been developed due to a demand for weight reduction, and the needs thereof have been increasing year by year. Therefore, when these latent hydraulic particles are used as an ALC plate, a large amount of these latent hydraulic particles can be expected. ALC (autoclaved light weight concret
e) Autoclaved lightweight cellular concrete, which is excellent in fire resistance, heat insulation and soundproofing, is widely used as a lightweight and durable building panel in houses and the like.
However, since the porosity is large, it is necessary to insert a reinforcing material such as a reinforcing bar in a place requiring strength such as a floor material. Recently, various sound absorbing plates have been developed in response to demands for noise, and their needs have been increasing year by year. Therefore, even when used as a sound absorbing plate, a large amount of these latent hydraulic particles can be expected. Normally, the sound absorbing plate having excellent sound absorbing properties has a large porosity, and thus has a low strength (for example, a compressive strength of 10 kg / cm ² or less). Therefore, at present, it is put in a support such as an iron frame to compensate for insufficient strength.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned conventional problems and to provide a lightweight multi-layer solid product which is lightweight and has high strength without a reinforcing material or a support. .

[0008]

Means for Solving the Problems In order to solve the above-mentioned problems, the inventors of the present invention have made various studies and found that a coating film containing tobermorite finer than tobermorite in a matrix on the surface of latent hydraulic particles was obtained. Is formed,
It showed high strength and small variation in strength. Furthermore, it has been found that a lightweight multilayer solidified product obtained by integrating the high-strength solidified product with a light-weight solidified product obtained by introducing pores into the solidified product is lightweight, has high strength without a reinforcing material, and has a small variation. The outline is a lightweight multi-layer solidified product composed of latent hydraulic particles and tobermorite, each layer containing a first tobermorite-containing coating film formed on the surface of the latent hydraulic particles, and a latent hydraulic material. A second tobermorite formed between the particles, wherein each latent hydraulic particle is bonded via the coating film, and the first tobermorite is finer than the second tobermorite,
It is characterized by having layers having different cross-sectional occupation ratios of pores. And, the thickness of the coating film is 0.05μ.
m or more, and the cross-sectional occupation ratio of pores of the solidified product is 20
% Or less and the cross-sectional occupation ratio of pores of the solidified material is 30%.
９５95%, and the sectional occupation ratio of the latent hydraulic particles is 6% of the sectional area of the solidified matter excluding the pores.
A preferred embodiment is 0 to 10%.

[0009] The pores observed in the polished cross section of the solidified product include spherical pores having a diameter of 0.1 mm or more (hereinafter referred to as first pores) and pores having a diameter of less than 0.1 mm (measured by the BET method). (Hereinafter, referred to as second pores). Pores when calculating the sectional occupancy of latent hydraulic particles, pores when calculating the sectional occupancy of pores,
In addition, the determination of the continuous air hole and the independent air hole employed the first air hole. The porosity is measured according to JIS R 2205.
The total porosity including the open pores and the closed pores was measured according to the measurement method (boiling method). The total porosity covers the first porosity and the second porosity. In addition, the communicating vent means a pore in which the pores are in a communicating state, and the independent pore means a pore in which the pores are not in a communicating state. The measurement of the cross-sectional occupancy ratio of the pores and the latent hydraulic particles is performed on the polished cross section of the solidified material. The first tobermorite has a fibrous or sheet-like shape (including a wound sheet-like shape), and has a length of 0.1 mm.
The thickness is less than 5 μm and the thickness is tens of angstroms or less.
On the other hand, the second tobermorite mainly formed in the matrix is in the form of petals or needles, and has a length of 1 μm.
As described above, the thickness is 500 Å or more.

[0010]

[Function] Average particle size of coal ash, blast furnace slag, shirasu, etc. 10
潜在 30 μm of latent hydraulic particles, calcium hydroxide, and water are mixed, and the mixture is poured into a mold. On top of that, a mixture of the above-described latent hydraulic particles, calcium hydroxide, and a foaming agent is poured. . This is cured at a relative humidity of 90% or more at a temperature of 60 to 70 ° C. for 4 days or more.
By autoclaving at 80 ° C. for 2 days or more, a lightweight multi-layer solidified product having a high strength and a small variation in strength can be obtained without a reinforcing material or a support, even if the autoclave is cured.

Although this mechanism is not clear, it is considered as follows. In a state where the latent hydraulic particles having an average particle diameter of 10 to 30 μm, calcium hydroxide, and water are mixed and poured into a mold, the fine particles of the raw material components are in a state of being dispersed with each other. When the latent hydraulic particles, calcium hydroxide, a foaming agent, and water are mixed and poured into a mold, the state of the upper layer is stabilized by the foaming agent itself, and the bubbles trapped by the foaming agent are stabilized. The bubbles and the raw material components are uniformly dispersed in the mixture without being united with each other. This mixture is dried at a relative humidity of 90% or more for 6 hours.
When cured at a temperature of 0 to 70 ° C. for a long time, the upper and lower layers react with the SiO ₂ component in the latent hydraulic particles, calcium hydroxide, and water to form a CSH gel. Also, the entrained bubbles in the upper layer become pores due to this curing. Therefore, after wet curing, the upper layer becomes porous with entrained pores dispersed therein, the lower layer becomes dense, and both the upper and lower layers become a soft structure containing water. In both the upper and lower layers, a coating film is formed on the outer peripheral surface of the latent hydraulic particles in this structure, and this coating film is formed of amorphous C- formed by the reaction between the latent hydraulic particles and calcium hydroxide. It is considered to be composed of SH gel. Thereafter, by performing autoclave curing at a high temperature for a long time, a fibrous or sheet-like coating film mainly composed of the first tobermorite is formed on the outer periphery of the latent hydraulic particles in both the upper and lower layers. This is because the C—S—H gel of the coating film is a crystalline first tobermorite (5CaO · 6SiO _2).
・ 5H ₂ O). The sample is not immersed in water during autoclave curing.

Conventionally, for ALC and sound absorbing materials using cement, pre-curing before autoclave curing has been carried out, but silica sand is used as an aggregate and the curing temperature is 30 to 40.
° C and the curing time is as short as 3 hours or less. This is simply to foam a foaming agent such as aluminum to solidify the cement. After the autoclave curing, a coating film mainly composed of the first tobermorite is hardly formed on the outer periphery of the silica sand.

[0013] In addition, tobermorite is also directly produced from latent hydraulic particles and calcium hydroxide by autoclaving, and this tobermorite is considered to be mainly a petal-like or needle-like second tobermorite (crystalline) to form a matrix. Can be The interface between the upper and lower layers is integrated after wet curing, and after the curing in the autoclave, the upper and lower layers are firmly joined due to mutual reaction at the interface, and no cracks or the like are observed. Higher strength than interface bonded by crimping, bonding, etc. As a result, each of the latent hydraulic particles is bonded to each other via the coating film, each of the latent hydraulic particles is firmly fixed to each other, and the high-strength solidified material layer is firmly fixed to the matrix, Hydraulic particles are in the same state as the above-mentioned strength solidified layer and have a structure in which a lightweight solidified layer in which a large number of pores are dispersed in a matrix is strongly integrated, and is lightweight and has high strength even without a reinforcing material. Thus, a solidified product having a small variation can be obtained.

[0014] Further, since this solidified product has a low cement content, the solidified product contains alite (3) contained in cement clinker.
CaO.SiO ₂ ) and belite (2CaO.SiO)
₂ ) No calcium silicate remains, and C-S-
H gel remains little. Therefore, the dimensional stability against water is also excellent. X-ray diffraction and thermogravimetric analysis (TG)
When the amount ratio of tobermorite and C—S—H gel was measured, it was confirmed that the weight ratio of tobermorite was 70% or more. In the solidified product of the present invention, hydrogarnet and zonotolite are not recognized.

It is preferable that the light-weight solidified material comprises a layer having a pore occupation ratio of 20% or less and a layer having a pore occupancy of 30% to 95%. This is because when the solidified material has no layer of 20% or less, sufficient strength cannot be obtained, and when there is no layer of 30% to 95%, the weight cannot be reduced. If it exceeds 95%, it will be difficult to keep the shape of the weight-reduced one. Note that there are two types of pores: continuous vents and independent pores. When used as an ALC, it is preferable that a layer having a high pore occupation ratio in cross section be an independent pore,
When air permeability and water permeability such as a sound absorbing material and a water permeable plate are required, it is preferable that a layer having a high pore occupancy ratio be a continuous air hole. When used as a lightweight panel such as ALC, it is more preferable that the layer having a high pore occupancy ratio in cross section be 30 to 70% in terms of strength. Also,
When used as a sound absorbing plate, the cross-sectional occupancy of pores in a layer having a high occupied cross-sectional occupancy is 50 to 9 in view of sound absorption characteristics.
It is more preferably 0%, the diameter of the communicating hole is preferably 100 to 2000 μm on average in the polished cross section, and the size of the communicating hole (gap connecting the pores) is 30 to 500 μm on average. Is preferred. When forming closed pores, higher alcohol sodium sulfate is used as a foaming agent, and latent hydraulic particles, calcium hydroxide, a foaming agent, and water are rotated by a kneader at 300 rpm for 5 minutes.
Mix at high speed for a minute. Thereafter, the mixture is poured into a mold and cured at a temperature of 60 to 70 ° C. in a wet state. After curing, the pores become closed pores by the action of this particular foaming agent. In the case of forming the continuous air holes, an ammonium salt of an alkyl allyl ether is used as a foaming agent, and high-speed kneading of latent hydraulic particles, calcium hydroxide, a foaming agent, and water is performed at 300 rpm for 5 minutes by a kneader. Then pour into the mold,
Cure at a temperature of 60-70 ° C in a wet state. The pores of the solidified product after curing are brought into communication by the action of the specific foaming agent. Although the reason is not clear, this foaming agent has a large amount of entrained air bubbles and is an ammonium salt, so that it is easily decomposed at a low temperature of 50 to 60 ° C. under an alkali such as calcium hydroxide. Is considered to be related to the formation of continuous pores.

In addition, it is preferable to add a foaming agent such as metallic aluminum powder together with the foaming agent at the time of kneading when forming the independent pores and when forming the continuous pores. This is because the addition of a foaming agent generates gas (hydrogen in the case of metallic aluminum powder) during wet curing, which increases the pore diameter and porosity of the solidified product, and achieves a lighter weight. These foaming agents also stabilize the bubbles generated by the foaming agent and make it difficult for the bubbles to coalesce. In addition, when an ammonium salt of an alkyl allyl ether is used, the bubbles generated by the foaming agent are formed by wet curing. The pores are also connected. On the other hand, when higher alcohol sodium sulfate is used, the pores formed by bubbles generated by the foaming agent during wet curing are not communicated with each other. In addition, the water content of the mixture needs to be 50 to 70% by weight with respect to the solid content in a layer having a high pore occupation ratio in cross section. If the amount is less than 50% by weight, foaming and entrainment of bubbles are not successful, and if it exceeds 70% by weight, sedimentation of latent hydraulic particles occurs. In the layer having a low pore occupation ratio, 35% by weight based on the solid content for enhancing strength.
You need to:

The sectional occupation ratio of the latent hydraulic particles is
It is preferably 60 to 10% of the solidified matter excluding the pores. More preferably, it is 50 to 30%. If the content is outside this range, the strength of the solidified product decreases. The reason is that when the cross-sectional occupation ratio of the latent hydraulic particles exceeds 60%, the generation of tobermorite decreases and the solidification becomes difficult, and when the cross-sectional occupation ratio of the latent hydraulic particles is less than 10%, This is probably because the latent hydraulic particles do not sufficiently serve as aggregates. This section occupancy ratio is 60
In order to make it 10% to 10%, the mixing ratio of latent hydraulic particles and calcium hydroxide was set to 8: 2 to 4: 6 by weight, the wet curing time was set to 4 days or more, and the autoclave curing time was set to 2 days or more.

Therefore, the obtained solidified product containing latent hydraulic particles has a high strength and a small variation in strength, despite having a layer having a large number of pores therein. 0.0 or less. In addition, those having continuous vent holes have good sound absorbing properties, so that they can be used as a sound absorbing material. In addition, since they have good dimensional stability to water, water permeability, and abrasion resistance, they have a water-permeable sidewalk board, etc. Can also be used as a water permeable plate.
Further, the solidified product of the present invention has good fire resistance and durability.
For this reason, the lightweight multi-layered solid containing the latent hydraulic particles of the present invention can be used in large quantities in a wide range of fields, and the latent hydraulicity in the raw material of the lightweight multi-layered solid containing the latent hydraulic particles is large. Since the mixing ratio of the particles is high, a large amount of latent hydraulic particles can be used.

The latent torsion particles, calcium hydroxide, a foaming agent and water are mixed, and the second tobermorite is cured by autoclaving in a sound absorbing material (using cement) and curing at a low temperature in the same short period as ALC. It is thought that the required amount of the first tobermorite-containing coating film formed in the matrix and joining each latent hydraulic particle is not formed, so that the latent hydraulic particles are not joined and the strength of the solidified product is not improved. Can be Here, when the latent hydraulic particles are small, they are lost by the reaction, and the effect of improving the strength is not brought about. On the other hand, when it is huge, it acts as a defect and lowers the strength. Therefore, an average particle size of 10 to 30 μm is required. In the coal ash, the bulk density is 1 g / cm ³ with high solidity so that the first tobermorite is generated around the particle.
The above particles are used. When silica sand or silica stone is used instead of the latent hydraulic particles, a coating film mainly composed of CSH gel is hardly formed when wet curing is performed. Calcium hydroxide as a calcium source gave good results in terms of strength enhancement. This is presumably because calcium hydroxide does not contain an SiO ₂ component or the like as compared with cement or the like, and thus acts directly as a stimulant, and as a result, high strength has been brought about. When only calcium oxide was used, it swelled in wet curing,
Cracks occurred in the solidified material. In the case where the latent hydraulic particles settle during wet curing, a small amount of Portland cement (20% or less of the weight of calcium hydroxide) may be added. As the latent hydraulic particles, coal ash is preferable in terms of strength. Among them, fly ash is more preferred.

In order to improve strength, the thickness of the first tobermorite coating film is preferably 0.05 μm or more,
It is more preferably at least 0.1 μm. By setting the wet curing time at 60 ° C to 70 ° C for 4 days or more, 0.0
A first tobermorite coating film of 5 μm or more could be obtained. This is presumably due to the fact that a large amount of CSH gel was formed on the outer peripheral surface of the latent hydraulic particles by humid curing at a relatively high temperature for a long time, and this was changed to tobermorite by the autoclave curing. 80 ℃
Above, the pores became huge and the strength of the solidified product decreased.

As described above, the light-weight multi-layer solidified product has two pores, but three or more multi-layers are also possible. As a form of the lightweight multilayer solidified product, the cross-sectional occupation ratio of pores is mainly classified into the following four types. The type in which the cross-sectional occupancy ratio of the pores between the two surfaces changes from low to high, the type in which the cross-sectional occupancy ratio of the pores between the two surfaces changes from low to high to low, A type that changes from high to low to high, and a mixed type as described above. In any case, it is preferable from the viewpoint of strength that the time for pouring each slurry be within 2 hours. Further, from the viewpoint of strength and water absorption, it is preferable that the foam flowing into the outer surface (the bottom surface or the upper surface of the mold) is not added with a foaming agent or a foaming agent. Since it is preferable in terms of strength that the distribution of the cross-sectional occupancy ratio of the pores changes continuously, it is better to adjust the amounts of the foaming agent and the foaming agent in each slurry so as to change continuously. When the mixing ratio of the coal ash and the calcium compound is also changed, it is preferable that the mixing ratio be changed continuously in terms of strength. Since the above is slightly inferior in dimensional stability and strength, use outdoors is not preferable.

[0022]

Next, the present invention will be described based on an example in which coal ash is mainly used as latent hydraulic particles. As coal ash used, not only pulverized coal ash generally generated,
Coal ash generated from a normal pressure or pressurized fluidized bed combustion power generation system may be used.

When mixing coal ash, calcium hydroxide, metal aluminum powder, a foaming agent and water with a kneader,
Additives such as binders, water reducing agents, water retention agents, waterproofing agents, fluidizing agents, shrinkage reducing agents, etc. may be added, and pearlite may be used to improve the strength of the solidified material, adjust the specific gravity, reduce costs, etc. , ALC waste, glass fiber (preferably alkali-resistant glass fiber), synthetic fiber (vinylon, nylon),
Pulp and the like can also be added. The foaming agent may be used in a preform method.

Using the raw material thus prepared, it is formed into a predetermined shape by a casting method. On this occasion,
It is preferable to perform the operation in a state where vibration is applied. Further, it is also possible to form a mold with a reinforcing material such as a reinforcing bar inserted therein.

(Examples 1 to 9) Coal ash (fly ash) having a bulk density of 1 g / cm ³ or more and an average particle size of 10 to 30 μm (Examples 1 to 8) and blast furnace slag (Example 9) are used. At the same time, calcium hydroxide having an average particle size of 10 μm is used, these are mixed in a weight ratio of 8: 2 to 4: 6, and 20 to 60% by weight of water and a foaming agent are added to the mixture to form a kneader. After mixing, various coal ash raw materials were prepared and cast. Here, the kneading machine used a spiral mixer, and kneaded at 300 rpm for 5 minutes. The metal aluminum powder used had an average particle size of 50 μm or less, and was added in an amount of 0.0 to 0.3% by weight based on the solid content of the coal ash raw material. The foaming agent used was an ammonium salt of an alkyl allyl ether (trade name: Hytenol manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), and a higher alcohol sodium sulfate (trade name: Emal manufactured by Kao). ~
0.1% by weight was added. In addition, Portland cement of 20% of the weight of calcium hydroxide was added. The different types of mixtures are poured into a mold (bottom 90 × 150 mm) to form two layers, which are cured at 60 to 70 ° C. for 4 to 7 days in a wet state (relative humidity 95%) to obtain a disc-shaped solidified base. (90 × 90 × 150 mm, thickness of each layer 45 mm). The solidified body thus obtained was subjected to autoclave curing at a temperature of 180 ° C. for 2 to 7 days. The measurement of the bulk density was based on the measurement method of JIS Z2504.

With respect to the solidified product thus obtained, the appearance, the pore state of each layer, the state of latent hydraulic particles and the state of the coating film were observed, and the compressive strength and sound absorption of the solidified product were measured. Table 1 shows the results. The polished sample was observed with a reflection microscope in order to observe the two-layer interface state of the obtained solidified product. This result is shown in FIG.
Shown in It is recognized that the interface is firmly fixed without defects such as microcracks. This photograph shows the formation of independent pores. In addition, the diameter of the continuous ventilation hole is 100 average for those having the continuous ventilation hole.
2,000 μm, and the average size of the communication holes is 30-5
00 μm. In addition, in observation of the polished surface, a diameter of 0.1
60% or more of the pores having a diameter of 1 mm or more, and 80% or more of the pores having a diameter of 1 mm or more have continuous air holes. The same applies to the case where independent pores are formed.
60% or more of the pores having a diameter of 1 mm or more, and 80% or more of the pores having a diameter of 1 mm or more are independent pores. Further, X-ray diffraction analysis of the obtained solidified product was performed. The chart is shown in FIG. Α- contained in coal ash particles in addition to tobermorite
Quartz and mullite peaks are observed. Further, a scanning electron micrograph and a transmission electron micrograph of the coating layer formed on the surface of the coal ash particles were taken. Figure 1
~ 2. In FIG. 2, the coating film of fine tobermorite is so fine that it is not clearly recognized, but is clearly recognized when it is enlarged as in FIG. In the case of Comparative Example 1, such a coating film of fine tobermorite was not observed. In addition,
By observing the appearance of the solidified product, the presence or absence of damage such as cracks in the solidified product and the strength of the shape retention were judged.
Marks and defective ones are indicated by crosses. The measurement of the compressive strength was in accordance with JIS A 1108.
That is, a metal plate having a diameter of 50 mm is placed on the upper and lower surfaces of the sample, and pressure is applied to the layers in parallel using an autograph.
The standard deviation was defined as the variation. Sound absorption coefficient is JIS A
According to 1405, thickness 5mm, no air layer, frequency 5
The normal incidence sound absorption coefficient was measured at 00 Hz. As described above, the examples using the coal ash particles and the blast furnace slag as the latent hydraulic particles have been described, but the present invention is not limited thereto, and the latent hydraulic particles such as silicate clay, volcanic ash, and diatomaceous earth are used. You may use it.

(Comparative Examples 1 and 2) In Comparative Example 1, using coal ash, the same procedure as in the example was carried out until casting (forming two layers), curing in a wet state at 40 ° C. for 3 hours, and then at 180 ° C. Autoclave curing was performed under the conditions for 2 days. Also,
Comparative Example 2 was carried out in the same manner as in the example, except that only one layer was poured. One layer had a thickness of 90 mm. Table 1 shows the results.

[0028]

[Table 1]

[0029]

As is clear from the above description, the light-weight multilayer solidified product according to the present invention has a high mixing ratio of latent hydraulic particles and layers having different cross-sectional occupation ratios of pores. is there. In addition, those having continuous air holes have good sound absorbing properties and water permeability. Therefore, it can be applied to a wide range of fields such as building materials such as building material panels and blocks, sound-absorbing boards, and water-permeable boards.
A large amount of latent hydraulic particles such as blast furnace slag can be effectively used, and the effect of the present invention is extremely large.

[Brief description of the drawings]

FIG. 1 is a transmission electron micrograph (× 24) showing a state in which fine tobermorite is formed on the surface of coal ash particles.
0000)

FIG. 2 is a scanning electron micrograph (× 800) of a fracture surface of a solidified product according to the present invention.

FIG. 3 is a reflection micrograph (× 15) of a polished cross section of a solidified product according to the present invention.

FIG. 4 is an X-ray diffraction chart of a solidified product according to the present invention.

Continuation of the front page (51) Int.Cl. ⁶ Identification code FI C04B 40/02 C04B 40/02 // (C04B 28/18 18:08 18:14 20:10) 111: 40 (56) References JP JP-A-56-73658 (JP, A) JP-A-49-20220 (JP, A) JP-A-5-310454 (JP, A) JP-A 8-208345 (JP, A) JP-A 8-208350 (JP, A) , A) JP-A-7-315951 (JP, A) JP-A-8-325073 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C04B 38/00 301 C04B 38/02 C04B 38/10

Claims (4)

(57) [Claims] 1. A light-weight multilayer solidified product composed of latent hydraulic particles and tobermorite, wherein a coating film containing a first tobermorite formed on the surface of the latent hydraulic particles, and latent hydraulic particles A second tobermorite formed therebetween, wherein each latent hydraulic particle is bonded via the coating film, and the first tobermorite is finer than the second tobermorite, A lightweight multi-layer solidified product containing latent hydraulic particles, characterized by having layers having different sectional occupation ratios. 2. The lightweight multilayer solid containing latent hydraulic particles according to claim 1, wherein the thickness of the coating film is 0.05 μm or more. 3. A layer in which the cross-sectional occupation ratio of pores of the solidified material is 20% or less, and a layer in which the cross-sectional occupation ratio of pores of the solidified material is 30 to 9
The lightweight multilayer solidified product containing latent hydraulic particles according to claim 1, comprising a layer that is 5%. 4. The lightweight multilayer containing latent hydraulic particles according to claim 1, wherein the cross-sectional occupation ratio of the latent hydraulic particles is 60 to 10% of the cross-sectional area of the solidified matter excluding pores. Solidified.