JPH09315843A - Composition for building exterior body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition capable of forming a building exterior body low in specific gravity and water absorption, excellent in strength and reduced in a production cost by using a cement, in which a fibrous material is incorporated as an essential raw material, and incorporating a specific lightweight aggregate. SOLUTION: The cement, in which the fibrous material (e.g. pulp fiber) is incorporated, is used as the essential raw material and 10-20wt.% fly as balloon is preferably incorporated as the lightweight aggregate. Since the fly ash balloon has high compression strength of >=10MPa compared to the conventional aggregate (e.g. perlite) and the 10MPa pressurization is applied to the molding of the building exterior body, the exterior body provided with a sufficient mechanical strength is obtained. Since the fly ash balloon contains 60% SiO2 , it causes the Pozzolan reaction with Ca(OH)2 liberated from C3 S (basic composition of A-lite) or C2 S (basic composition of B-lite) or C3 S2 H3 (afwilite) as the reaction product, thus the structure of the exterior body is densified.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition for a building exterior such as a roofing material or a wall material containing a lightweight aggregate as a main raw material and a cement mixed with a fiber material.

[0002]

2. Description of the Related Art Conventionally, in known examples of this type of building exterior composition, perlite, shirasu balloon, vermiculite, shale, etc. have been used as the lightweight aggregate.

[0003]

However, in the building exterior body obtained from the above-described conventional composition for building exterior body, the specific gravity can be sufficiently reduced due to the properties of the lightweight aggregate contained therein. Or there is a defect that the water absorption rate is high (especially in cold regions, if the water absorption rate is too high, the building exterior is damaged by frost damage and damaged) (the lightweight aggregate used in these conventional examples. (See Table 1 for each lightweight aggregate, showing the specific gravity and water absorption of the building exterior obtained when 10% of each is added to a general composition for building exterior). That is, since the low specific gravity as an aggregate and the low water absorption rate are properties that are generally contradictory to each other, the lightweight aggregates used in these conventional examples have a reduced specific gravity to form a building exterior body. Although the effect of weight reduction is high, at the same time there is a problem with durability due to high water absorption rate (perlite, shirasu balloon, vermiculite). On the other hand, it is possible to keep the water absorption rate low, but lower the specific gravity In both cases, the effect of reducing the weight of the exterior body is low (shale), and thus neither the effect of reducing the weight of the exterior body of the building nor the ability to secure a low water absorption rate are compatible with each other. The object of the present invention is to provide a building exterior body that is sufficiently lightweight and has a sufficiently low water absorption rate in view of the above drawbacks found in the above-described conventional composition for building exterior body. Another object of the present invention is to provide a composition for a building exterior body.

[0004]

In order to achieve the above object, the composition for a building exterior according to the present invention is characterized in that fly ash balloons are blended as the lightweight aggregate.

[Advantages of the Invention] Due to the above-mentioned characteristic configuration,
The composition for a building exterior body according to the present invention has a low specific gravity.
The fact that the water absorption is low is a conflicting property.
Contrary to the custom of carcass aggregate, it has two characteristics: low specific gravity and low water absorption.
Using a fly ash balloon that also has conflicting properties
Therefore, it is also light enough as shown in Table 1.
The exterior of the building that has
The unique effect of being able to obtain is obtained. Also,
The compressive strength of fly ash balloon is 10 MPa or more
And the lightweight aggregates used in the above-mentioned conventional
The compressive strength is higher than about 2.7-7 MPa)
Pressing pressure when using press molding in the exterior body molding process
As a pressure higher than 10 MPa can be adopted,
The effect that a building exterior body with sufficient mechanical strength can be obtained
The fruit was also obtained. Furthermore, the fly ash balloon is made of Si
O_TwoSince it contains about 60% of the component, it is included in the composition for building exterior.
When the cement to be hydrated undergoes a hydration reaction, fly ash bar
Said SiO in the runes_TwoIngredient is C_ThreeS (of Alite
Basic composition) and C_TwoFree from S (the basic composition of Belite)
Ca (OH)_Two, Or C as a reaction product_ThreeS
_TwoH_Three(Affilites) and pozzolanic reaction, building
It was also possible to obtain the effect of making the structure of the outer package more dense.
The content of the fly ash balloon is 10 to 20.
If it is in the weight% range, the strength as a building exterior is sufficient.
And composition for building exteriors, which is relatively low in manufacturing cost
Is obtained, which is more convenient.

[0006]

[Table 1]

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 schematically shows an apparatus for manufacturing a roofing material 150 as an example of a building exterior body of the present invention.
The slurry 100 is first made into a paper by the wet paper making device 1, formed by the forming device 2, and after natural curing, the autoclave 3
Then, the roofing material 150 is obtained as a finished product that is further cured by high-temperature and high-pressure steam. The slurry 100 includes silica sand, mica, cement, pulp fibers, as shown in FIG.
And a solid part consisting of fly ash balloons and water. The wet papermaking apparatus 1 is provided with a vat 12, a cylinder cylinder 14 rotatably housed in the vat 12, a conveyor belt 10 made of felt, a suction dewatering mechanism 16, and a rotatably making roll 20. . The molding device 2 mainly comprises a press 200.

The slurry 100, which has been preliminarily adjusted, well mixed and degassed, is introduced into the vat 12, and after being made into a film by the outer peripheral surface of the cylinder cylinder 14 rotating counterclockwise in FIG. As it is, it is transferred to the conveyor belt 10 moving at a speed substantially equal to the peripheral speed of the round net cylinder 14, and the transferred slurry 100 becomes a continuous strip-shaped seed film 110 formed on the conveyor belt 10.
The seed film 110 is appropriately dehydrated by the suction dehydration mechanism 16, and then wound and laminated by the making roll 20 until a predetermined thickness is obtained, and then cut by a wire and flattened, and further suitable. The unit molded body 130 is cut into lengths. The unit molded body 130 is compression-molded by the press 200 of the molding apparatus 2 at a pressure exceeding 10 MPa to obtain a predetermined shape and density.
It will be 40. The molded body 140 is stored in the autoclave 3 after being naturally cured for about one day. Autoclave 3
Is maintained at a temperature condition of 150 to 180 ° C. for 8 to 20 hours, the molded body 140 exposed to the high temperature and high pressure steam inside the autoclave 3 has a low hydration reaction of the cement being compounded rapidly. A roofing material 150, which is an example of a building exterior body composition having a high shrinkage and a high density, can be obtained.

Further, in the roofing material 150 using the composition for a building exterior according to the present invention, fly ash is used in the high temperature and high pressure steam curing in the autoclave 3 due to the fact that the fly ash balloon is used. The SiO ₂ component forming the balloon is Ca (OH) ₂ liberated from C ₃ S (basic composition of alite) or C ₂ S (basic composition of belite), or C as a reaction product.
Pozzolanic reaction with ₃ S ₂ H ₃ (affylite),
The structure of the roofing material 150 becomes finer.

[Another Embodiment] <1> The slurry 10 as shown in the above-described embodiment.
0 in place of the step of papermaking by the wet papermaking apparatus 1,
The same slurry 100 ′ may be formed in a single layer or multiple layers by the flow-on method. FIG. 2 shows an example of the equipment required for the manufacturing method according to this another embodiment, taking the case of forming the layer as one example. In FIG. 2, the slurry 100 ′ prepared in the same manner as in FIG. 1 is once stored in the head tank 30 and then supplied to the flow box 36 under the control of the flow meter 32 and the flow rate adjusting valve 34. A rectangular discharge port is provided in the lower part of the flow box 36, and the slurry 100 ′ discharged from the discharge port in a constant amount is conveyed to the right by a belt conveyor 38 made of felt which advances to the right side of the drawing. As a result, a thin continuous body 110 'that extends long right and left is formed. When the continuous body 110 ′ is dehydrated to a predetermined level by the suction dehydration mechanism 16 ′ provided on the lower part of the belt conveyor 38, it is further squeezed by the press roll 40 provided on the upper part of the belt conveyor 38 to be dehydrated. At the same time, it becomes a continuous body 112 whose thickness is adjusted to a predetermined dimension. Next, the continuous body 112 is appropriately cut by the cutter mechanism 50 into a plurality of unit molded bodies 114 having a predetermined length, and then press-molded by the molding apparatus 200 to obtain a molded body 140 ′. The subsequent steps are the same as those in FIG. 1, and after the natural curing and the high temperature and high pressure steam curing by the autoclave 3, the roofing material 150 ′ is obtained. <2> The composition for a building exterior body according to the present invention comprises the amount of fibers,
It can be applied as a wall material by appropriately adjusting the slurry concentration, the shape of the molded body, and the like.

[Brief description of drawings]

FIG. 1 is a schematic view of a roof material manufacturing apparatus according to the present invention.

FIG. 2 is a schematic view of another embodiment of FIG.

[Explanation of symbols]

 10 Conveyor Belt 12 Bat 14 Circular Cylinder 20 Making Roll 100 Slurry 110 Seed Membrane 150 Roofing Material

Claims (2)

[Claims] 1. A composition for a building exterior body, which is mainly composed of cement mixed with a fibrous material and which also contains a lightweight aggregate, for a building exterior body containing fly ash balloons as the lightweight aggregate. Composition. 2. The composition for a building exterior body according to claim 1, wherein the content of the fly ash balloon is in the range of 10 to 20% by weight.