JPH0228542B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a large ALC panel that is integrally molded, and more particularly to a large ALC panel in which panel mounting fittings are embedded during molding.

Conventional large ALC panels are made by assembling multiple 600mm wide ALC panels, which poses problems in terms of strength due to the lack of integrity as a panel.Also, there are seam marks between the panels, making them undesirable in terms of design. It was rare. The present invention solves these problems.

Conventionally known manufacturing methods for integrally molded ALC panels can be roughly divided into two methods: the vertical casting method, in which multiple panels are simultaneously molded vertically in a formwork, and the method in which panels are formed horizontally in a formwork. It can be roughly divided into flat molding methods.

The vertical driving method is a method in which the main components are usually silica stone as a silicic raw material and ordinary Portland cement and quicklime as calcareous raw materials, which are foamed with aluminum powder, hardened and demolded, and then cut with piano wire. On the other hand, the flat pouring method uses silica stone, ordinary Portland cement, and quick setting cement as main components and forms air bubbles with a foaming agent. For both methods, autoclave curing is performed after hardening and demolding.

In the case of the vertical casting type, mortar slurry is poured from the top of the formwork, so defects such as voids, cavities, and coarse bubbles are likely to occur due to the connection of air bubbles and air entrainment due to the impact of falling. In addition, in the case of the vertical hammer type, since the mortar travels a long distance due to foaming, a low viscosity mortar (about 2000 cp) is required, which tends to cause settling of the raw material.
There is a difference in specific gravity of more than 4% between the bottom and top of the hardened mortar, resulting in a lack of uniformity in quality, so the vertical height is normally limited to about 600mm, and it is not possible to manufacture panels with a larger width than that. It is difficult. In particular, if the embedding metal fittings are fixed to the reinforcing reinforcing bars in advance and then buried in the panel, the foaming will be severely damaged, and the strength will be reduced due to the occurrence of internal defects such as voids, cavities, and coarse air bubbles, as well as the difference in specific gravity. This becomes noticeable, and the pull-out strength of the embedded metal fittings varies greatly within the same panel. Therefore, in order to improve the installation safety of the panel, it has been necessary to use an uneconomical design such as densely arranging reinforcing bars around the embedded fittings. Additionally, during molding, the expansion of the mortar slurry due to the foaming of aluminum powder pushes up the reinforcing reinforcing bars, making the positioning accuracy of the mounting brackets fixed to the reinforcing bars very poor, making it difficult to install the panels in the specified positions at the construction site. Not only does this require a lot of time and effort, prolonging the construction period and increasing construction costs, but it also requires expensive panel mounting equipment that has a function to absorb positional errors of embedded metal fittings.

On the other hand, in the case of the flat hammer type, the upper surface, which is leveled with a knife before curing with high-temperature and high-pressure steam, has the disadvantage that it becomes a dense, smooth surface with poor adhesion of finishing materials. Furthermore, since rapid-setting cement is used, hydrogarnet crystals are formed inside the product, which causes a decrease in strength and increases cost.

The present invention solves the above-mentioned conventional drawbacks, and is a large ALC panel with uniform air bubbles, small differences in specific gravity within the panel, and the ability to manufacture wide panels and facilitate the creation of openings.

The panels of the present invention are manufactured by, for example, a flat hammering method without using raw materials that produce hydrogarnets such as quick-setting cement, and after curing in high-temperature, high-pressure steam, the entire surface and/or back surface of the panel can be cut. can. Through the cutting process, the front and back surfaces of the panels of the present invention appear to have smooth cut surfaces at first glance, but due to the cutting, fine concave areas with air bubbles are exposed almost uniformly over the entire surface, and a moderately rough surface is formed, making it extremely difficult for the adhesion of finishing materials. A suitable surface is formed. From the point of view of finish adhesion, it is preferable to form bubbles with aluminum powder rather than with a foaming agent. The finish material adheres very well to the surface where the piano wire was cut before autoclaving.

Further, in the panel of the present invention, when the absolute dry bulk specific gravity of any two parts within the panel is ρ ₁ and ρ ₂ (ρ ₂ ≧ρ ₁ ),
ρ ₂ −ρ ₁ /ρ ₁ is always 0.02 or less, preferably 0.005 or less, and the panel has almost no difference in specific gravity within the panel, that is, there is almost no difference in specific gravity. One of the reasons why it was not possible to obtain wide width panels with conventional ALC panels is that the difference in specific gravity in the inner width direction of the panel, that is, the difference in rigidity and strength, increases, which causes uneven panel deflection and local breakage. This is because it makes it easier to raise money. This point is particularly problematic in the case of apertured panels. The measurement of the difference in specific gravity within a panel uses a 10 cm cube cut out perpendicular to the panel in the thickness direction of the panel as a sample, and other measurement conditions are conducted in accordance with JIS A 5416.

The panel dimensions of the present invention include a panel width of 900 mm or more, preferably 1,500 mm or more, a panel length of 2,400 mm or more, preferably 3,000 mm or more, and a panel thickness of 100 mm or more.
It is 121mm or more.

As raw materials for the panels of the present invention, raw materials commonly used in ALC can be used, but materials that produce hydrogarnet through autoclave curing are not preferred. The C/S of the raw material is preferably 0.8 or less. For steam curing in an autoclave, general conditions using saturated steam with a gauge pressure of 8 to 12 kg/cm ² are used. The bulk specific gravity of the matrix portion (the portion excluding reinforcing bars, etc.) of the product is preferably 0.40 to 1.00, particularly preferably 0.45 to 0.60.

The panel of the present invention can be subjected to cutting processing on the surface of the panel after autoclave curing, if necessary.
The surface impregnated with a mold release agent and/or the surface leveled with piano wire or the like can be cut out. Due to the cutting process, the panel surface becomes a smooth surface with exposed air bubbles, and because the difference in specific gravity within the panel is small, the air bubble pores are uniform over the entire surface, so the paint penetrates evenly, reducing uneven coating of exterior paint and improving adhesion. However, the amount of coating will also decrease.

In addition, in the panel of the present invention, the maximum width of the void that exists around the reinforcing bars is at most 1/2 of the diameter of the reinforcing bars, so the adhesion strength between the reinforcing bars and the ALC matrix (parts other than reinforcing bars, etc.) is high, and the performance of the panel is improved. It is excellent.

The present invention will be explained in detail below based on examples.

As shown in FIGS. 1 and 2, the formwork bottom plate 1
After moving the side frame member 2 in parallel according to the dimensions of the ALC panel, fix it freely. A mold release agent is applied to the mold bottom plate 1 and the side frame members 2 in advance. The size of the formwork bottom plate 1 is 1800mm to 2600mm wide.
mm, length 4000mm to 8000mm, side frame member 2 height 100mm
It is possible to produce items with a diameter of ~250mm. In addition,
It is also possible to produce a plurality of panels by dividing the formwork in the width direction and length direction within the dimensions of the formwork. Although the formwork bottom plate 1 shown in FIG. 2 is for producing flat panels, it is also possible to produce panels with irregular cross sections by using a bottom plate with unevenness. Next, the reinforcing reinforcing bars 3 configured in advance are installed in the formwork, and are fixed in accurate positions by a reinforcing bar fixing jig 5 using the embedded fittings 4 fixed to the reinforcing bars 3. Similarly, the spacer 6 for forming the opening is also fixed at a precise position to prevent mortar slurry from entering the opening. Spacers are available in several sizes, ranging from 300mm to 2100mm in width, depending on the size of the opening. Spacer materials include iron, stainless steel, plastic, rubber,
Aluminum etc. are used. Mortar slurry is injected into the formwork prepared in this manner by a flat pouring method. The mortar slurry composition is silica powder.
50 parts by weight, 40 parts by weight of ordinary Portland cement,
10 parts by weight of quicklime, 60 parts by weight of water, aluminum powder
It is 0.07 part by weight. Since the injected mortar slurry falls over a shorter distance than in the vertical driving method, there is little accumulation of air bubbles due to impact from falling, and the occurrence of coarse air bubbles, voids, cavities, etc. due to air entrainment.
Furthermore, since the foaming height is low, it is possible to inject a highly viscous mortar slurry, and as a result, the amount of molding water can be reduced, and as a result, the curing time can be shortened.
The time required for demolding can be reduced to approximately one-half to one-third compared to the conventional vertical hammering method.
This high viscosity mortar slurry (over 2500cp)
Because there is less separation and sedimentation of raw materials, it is possible to reduce the variation in specific gravity within the formwork, and it is possible to produce large panels with uniform strength. In the conventional vertical driving method, the difference in specific gravity between the upper and lower parts of the mortar slurry is 4% or more, and this difference in specific gravity exists in the width direction of one panel, but in the method of the present invention, the mortar slurry is foamed. Since the height is kept low, the difference in specific gravity between the upper and lower parts of the mortar slurry is about 0.4%, and there is almost no difference in specific gravity in the width direction of one panel. As a result, it is possible to secure the pull-out strength of the embedded fitting, which is subjected to a large concentrated load after the panel is attached. The specific gravity referred to here is a value measured according to the test method specified in JIS A 5416 "Lightweight cellular concrete products cured in an autoclave". Furthermore, there is almost no pushing up of reinforcing reinforcing bars by mortar slurry during foaming, making it possible to produce panels with extremely good positioning accuracy of reinforcing bars and hardware. In addition, the accumulation of moisture and air bubbles in the mortar slurry that occurs above the reinforcing bars is very small, and it is extremely rare for large voids to remain after autoclave curing. When the mortar slurry injected in this way reaches a predetermined strength after pre-curing, the side frame is removed, the spacer for the opening is removed, the panel is cut with piano wire, etc. to the predetermined panel thickness, and then autoclave cured. I do.

Therefore, in the panel of the present invention, the positional accuracy of the reinforcing bars and the hardware are good, and since the reinforcing bar fixing jig 5 is used to support the panel perpendicularly to the bottom surface 1 of the formwork, the mortar is semi-plastic. By vertically pulling out the reinforcing bar fixing jig 5 once the reinforcing bar has completely hardened, it is possible to create an opening with good positional accuracy that continues from the panel surface to the embedded metal fitting.

X-ray diffraction of the composition after autoclave curing reveals the presence of tobermorite crystals and quartz when the siliceous raw materials used in the present invention, ie, common Portland cement and quicklime, are used.

On the other hand, when alumina cement is used as the quick setting cement in the conventional flat casting method,
In addition to tobermorite and quartz, hydrogarnet crystals that can be confirmed by X-rays are also observed. The strength development of this hydrogarnet crystal is extremely low, and when it coexists with quartz, the panel strength is significantly reduced, and in order to obtain the same strength as a panel that does not use alumina cement, it is necessary to increase the panel specific gravity. This results in damage such as an increase in the amount of raw materials used and an increase in the weight of the panel.

Next, the panel that has been cured in the autoclave is finished by cutting the surface in contact with the bottom of the mold, cutting off the part impregnated with the mold release agent, and smoothing the panel surface. Since this cutting process is performed by machining, the plane accuracy is extremely excellent. Moreover, since the part impregnated with the mold release agent is removed, no color unevenness is observed on the panel surface. Furthermore, since the surface of the panel is such that the cross section of the bubbles is exposed as shown in FIG. 3, the adhesion of the finishing paint is good and there is little variation in adhesion strength. The finishing material adhered extremely well to the surface where the piano wire was cut before autoclave curing.

By the method explained above, a panel with a width of 1800 mm, a length of 3700 mm, and a thickness of 125 mm with embedded metal fittings installed at the four corners of the panel.
Bulk specific gravity at both ends of the panel in the width direction (ALC matrix part) obtained by manufacturing a large-sized ALC panel (mm)
When measured, it was confirmed that ρ ₂ −ρ ₁ /ρ ₁ were all within 0.02. Dimensional accuracy, length and width
The thickness was within 1.0 mm and the thickness was within 0.5 mm. In addition, the embedded metal fittings were placed in the predetermined positions with good precision.

As described above, the present invention solves the problems of the conventional vertical hammering type and flat hammering type, and has small variations in specific gravity and strength, low raw material costs, and the ability to provide a large opening. This is a large ALC panel with many features such as

[Brief explanation of drawings]

Fig. 1 is a perspective view of a formwork used in an embodiment of the present invention, Fig. 2 is a sectional view thereof, and Fig. 3 is a formwork according to the present invention.
FIG. 2 is an enlarged cross-sectional view of the ALC panel after cutting. 1... Formwork bottom plate, 2... Side frame, 3... Reinforcement bar, 4...
Embedded metal fittings, 5... jig for fixing reinforcing bars, 6... spacers for openings, 7... ALC panels, 8... bubble cross sections.

Claims (1)

[Scope of Claims] 1. A high-temperature, high-pressure steam-cured lightweight cellular concrete (hereinafter referred to as ALC) panel whose main raw materials are powdered silicic acid raw materials and calcareous raw materials, and the absolute dry bulk specific gravity of any two parts in the panel is ρ. ₁ , ρ ₂ (ρ ₂ ≧ρ ₁ ), ρ ₂ - _{ρ 1} /ρ ₁ is always 0.02 or less, and two or more panel mounting embedding fittings are drilled and embedded on one surface of the panel. Panel width characterized by
900mm or more, panel length 2400mm or more, panel thickness
Large ALC panel over 100mm.