JPH08144404A - Structure of butt joint between light-weight cellular concrete panels - Google Patents

Abstract

PURPOSE: To prevent cracks from occurring in the vicinity of end faces in the longitudinal direction of a light-weight cellular concrete panel, in the case where the light-weight cellular concrete panels are attached to a structural building frame and are joined to each other by filling cement mortar between the panels neighboring with each other. CONSTITUTION: Specified cement mortal is filled in a space part 18 formed between end faces in the longitudinal direction of light-weight cellular concrete panels 14 neighboring with each other. The property of the specified cement mortar filled is as follows, that is, cracks 22 are laterally produced on a rod-like hardened object 21 formed at the time when the specified cement mortar is allowed to harden. In this case, since the hardened object 21 contracts as blocks in the contraction thereof, strain owing to the contraction thereof has no adverse effect on the whole of the light-weight cellular concrete panels 14 to which the hardened object 21 adheres. Therefore, the light-weight concrete panels 14 per se do not crack.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure in which any two lightweight aerated concrete (ALC) panels are butted and attached to a structural frame of a building.

[0002]

2. Description of the Related Art When constructing an outer wall or floor of a building, cemented, sand, and sand are placed in the space formed between the long side edge surfaces of two arbitrary ALC panels. Kneading water, while pouring so-called cement mortar, burying one end of joint rebar in the mortar, the other end of the joint rebar exposed from the end of the cured product of the mortar to the structural frame of the building AL fixed
Conventionally, a C-panel butt structure has been generally adopted.

[0003]

This prior art has the advantages that it can be easily and inexpensively constructed and that adjacent ALC panels can be firmly joined together, but there is still room for improvement in the following points. . As shown in FIG. 3, the adjacent ALC panels 1 and 2 and the hardened material 3 of cement mortar hardened between them are firmly bonded. However, after a long period of time, the dry shrinkage rates of the ALC panels 1 and 2 and the cured product 3, especially the dry shrinkage rates in the longitudinal direction (vertical direction in FIG. 3) are significantly different, and the physical strength such as tensile strength is different. Since the properties are different, cracks 4 may run in the longitudinal direction in the vicinity of the longitudinal facets of the ALC panels 1 and 2 having smaller shrinkage and physical properties than the cured product 3. An object of the present invention is to provide an ALC butt structure capable of completely suppressing the occurrence of the crack.

[0004]

In order to solve the above-mentioned problems, the present invention provides a structure for attaching the ALC panel to a structural frame of a building by abutting the long side edge faces of two arbitrary ALC panels, It is said that a mortar hardened product having a crack running in the transverse direction is interposed in a space formed between the long-side small edge faces, and one end of a joint rebar embedded in the mortar hardened product is fixed to the structural frame. Adopt means.

[0005]

Function: A specific cement mortar is filled in the space between the edge faces formed by abutting the edge faces of the long sides of the arbitrary two ALC panels. Then, the cement mortar is hardened and at the same time, the moisture in the cement mortar is partially absorbed by the ALC panel. Further, the cement mortar is hardened and the ALC panel absorbs moisture, and at the same time, the cement mortar, which is being hardened, is bonded to the ALC panel and the hardened product shrinks.

However, at the initial shrinkage of the cured product, the adhesive strength between the cured product and the ALC panel and the resistance of the ALC panel for preventing the shrinkage movement of the cured product are large, but the tensile strength is low, so that the curing is difficult. The object breaks and a crack runs in the transverse direction. This phenomenon can be visually recognized by observing the appearance of the cured product after a long time, for example, 24 hours, after filling the space portion with the cement mortar. In the present invention, a specific cement mortar having such characteristics is used.

Since the cured product is thus broken everywhere, even if there is a place where the cured product and the ALC panel are firmly joined, the contraction in the longitudinal direction of the ALC panel follows the contraction of the cured product. There is nothing to do. Therefore, in the ALC panel having a smaller shrinkage rate and a smaller physical property than the cured product, cracks do not occur in a portion in the vicinity of the front face in the longitudinal direction where joint reinforcement is not present.

[0008]

Embodiment 1 Next, one embodiment of the present invention will be described with reference to the drawings. First, cement mortar was prepared by mixing 100 parts by weight of cement with 150 parts by weight of ALC crushed product having a water content of 25% by weight and 120 parts by weight of water. The ALC crushed product used at this time passed through a sieve having a mesh interval of 3 mm, and 60% by weight thereof
Is 1.2 mm or less and exceeds 0.15 mm.
5 parts by weight is 0.15 mm or less, 5% by weight is 1.2
It was a crushed product exceeding mm.

JIS of cement mortar prepared as described above
The flow value by the “physical test method for cement” specified in R5201 was 210 mm, which was almost the same as the flow value of cement mortar usually used in this field.
Moreover, when the viscosity of the cement mortar was measured with a B-type viscometer manufactured by "Tokimec", it was 1480c.
It was ps.

Next, assuming a part of a building, as shown in FIG. 1, an experimental structural body having H-shaped steel with a span of 3000 mm as a beam 11 was constructed. Then, a ruler angle 13 made of L-shaped steel was welded and fixed to the upper flange 12 of the beam 11. ALC panel (length 2990 mm, width 599 mm, thickness 10 Omm) 14 that should be built on the structural frame of a formal building is in two layers above and below (interlayer spacing D is 10 m).
m) and 4 layers of each layer were built. In this installation, a vertical wall plate 15 having a thickness of 6 mm was welded to the ruler angle 13 at an interval substantially the same as the width of the ALC panel 14. As shown in FIG. 2, a communication hole 19 that allows passage of cement mortar, which will be described later, is provided substantially in the center of the vertical wall plate 15. The passage hole 19 was provided with a tongue piece 20 for positioning the joint rebar 16.

Next, the four ALC panels 14 are first built in the structural body in order from the corners of the lower layer. During the assembling work, both corners of the vertical wall plate 15 (only one corner in FIG. 2). An aluminum nail (not shown) was driven into the ALC panel 14 through a temporary fixing nail hole 17 (not shown) to temporarily fix the adjacent panels 14 to the vertical wall plate 15.

Then, the previously prepared cement mortar was filled in the cylindrical space 18 formed between the adjacent ALC panels 14. Inserting a 100 mm joint rebar 16 into the passage hole 19 of the vertical wall plate 15,
The central portion was welded and fixed to the tongue piece 20, one end portion was inserted into the filled cement mortar, and the other end portion was projected above the vertical wall plate 15.

When the lower ALC panel 14 is fixed to the structural body in this manner, four ALC panels 14 are arranged on the upper layer of the row.
Panel 14 It was built in the structural body in the same manner as above. And
The cement mortar was filled in the space 18 formed between two adjacent ALC panels 14. If this mortar is left for 24 hours, the ALC panel 14
It was confirmed in the next work of removing the ALC panel that the cured product became a rod-shaped cured product 21 during the interval.

Of the ALC panel 14 built in this way, the ALC panel 14 built last in each of the upper and lower layers
Each was removed, and the appearance of the cured product 21 was observed. As a result, it was observed that cracks 22 were running in the transverse direction at intervals of about 20 cm in the cured product 21 in a portion where joint rebar was not embedded.

After the ALC panels 14 of the upper and lower three layers built in the structural body are left indoors as they are for one month, the structural body is swung in the longitudinal direction of the beam 11. A static in-plane deformation test was conducted. The test conditions were a deformation rate of 0.1 mm / sec, an interlayer deformation angle of 1/200, and a test time of 1 minute. As a result, no cracks were generated in the vicinity of the long side edge of the ALC panel 14 as in the prior art (see FIG. 3).

[0016]

[Example 2] Next, this experiment was carried out in accordance with Example 1 by changing the particle size and distribution of the ALC crushed product, the mixing amount of water, etc. variously, based on 100 parts by weight of cement. The experimental conditions are shown in Table 1.

[0017]

[Table 1]

When the ALC panels 14 are built in the structural body, the space 18 between the adjacent ALC panels 14 is formed.
In a state where the cement mortar is filled in, the gap D between the panels 14 when filled (in the construction of this field,
It was observed whether or not the mortar flows out from the outer surface of the panel because the formation of a gap is usually inevitable up to about 3 mm). Then, a static in-plane deformation test was performed on the ALC panel obtained in the experiment in which the filling state was good and the mortar did not flow out.
The results are shown in Table 2.

[0019]

[Table 2]

From the results shown in Table 1, it was confirmed that the cement mortar according to claim 2 was used and the structure according to claim 1 was obtained.

[0021] The present invention skillfully utilizes the bonding force between the cured mortar and the ALC panel and the difference in shrinkage performance between the two, and follows the basic technical idea of preventing cracks that tend to occur in the ALC panel. The above-described embodiment can be partially modified and carried out within a range in which the effect is not significantly impaired. For example, a portion of the ALC crushed material can be replaced with 20% by volume (based on the weight of both) of silica stone powder, sand or fly ash, which preferably passes through a mesh size of 3 mm of the sieve.

In the embodiment, one end of the joint rebar is embedded in a hardened cement mortar, and the other end is integrated with the other end of the upper or lower joint rebar and fixed by welding or cement mortar. Although fixed to the structural body (including the ruler angle) via the cured product, the other end of the joint rebar may be fixed directly or indirectly by other means. The point is that the corners of the ALC panel may be fixed to the structural body. In the present invention, these aspects are also within the technical scope. The present invention can also be applied to a mode in which ALC panels are used as partitions, floors and roofs.

[0023]

As described above in detail, according to the present invention, when the ALC panel is applied to the structural frame, the physical properties of the hardened cement mortar that are interposed between the adjacent ALC panels are changed, so that the ALC after the installation is changed. It has an excellent effect that it does not cause cracks that tend to occur near the longitudinal direction of the panel.

[Brief description of drawings]

FIG. 1 is a partial perspective view showing a main part of the present invention.

FIG. 2 is an enlarged view of a main part, which also shows the main part in an enlarged manner.

FIG. 3 is a perspective view of a main part showing a conventional technique.

[Explanation of symbols]

 11 Structural frame 14 Lightweight cellular concrete panel 16 Joint rebar 18 Space 21 Cement mortar hardened product 22 Crack

Claims (2)

[Claims] 1. In a structure for attaching the lightweight cellular concrete panels to the structural frame (11) of a building by abutting the long side edge faces of two arbitrary lightweight cellular concrete panels (14), a crack (22) is transversely present. The cement mortar hardened product (21) running in the space is interposed in the space portion (18) formed between the long side edge surfaces, and one end of the joint rebar (16) embedded in the hardened mortar is Butt structure of lightweight cellular concrete panels fixed to the structural frame. 2. The mortar cured product (21) is a lightweight cellular concrete crushed product which passes through a sieve having a mesh spacing of 3 mm with respect to 100 parts by weight of cement, 50% by weight or more of which is 0.15 to 2 5 pieces of crushed material in the range of 0.5 mm
The butt structure for a lightweight cellular concrete panel according to claim 1, which is a cured product obtained by mixing 0 to 250 parts by weight and water at a ratio of 80 to 150 parts by weight.