JPH03293473A - Cement-based thin walled formwork - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to concrete pouring formwork for buildings.

(Conventional technology) Conventionally, as formwork for pouring concrete in buildings, plywood was used, which required scraping and removal after the concrete had hardened, and concrete formwork was used, which did not require removal and was integrated with the concrete being poured. There is a type of cast-in formwork (also called permanent formwork). Recently, thin-walled driving forms made of high-strength mortar have also come into use.

(Problems to be Solved by the Invention) However, according to the conventional plywood formwork, it is necessary to demold the formwork after concrete is poured, and the remaining materials are discharged during demolding. processing is required.

In addition, one of the conventional pouring formworks that uses concrete with normal bending strength requires a minimum thickness of 50 mm, is heavy, and requires a large crane, which is disadvantageous from a structural standpoint. In many cases, it cannot be recognized as a building frame, and the cross-sectional area of the formwork becomes large, which is disadvantageous in terms of floor space. In addition, it is difficult to use it at small and medium-sized sites where large cranes cannot be installed.

The molds made of high-strength mortar that have been used in recent years have been developed to solve the above-mentioned problems, or they have the following problems. Firstly,
The dimensions of beams and columns often differ depending on the specifications of the building, and when creating an integrally molded object with a U-shaped cross section in a factory, as in the past, there is a tendency to use more formwork than necessary. .

In view of the above-mentioned problems, the present invention does not increase the number of types of members at the time of production even when the dimensions of the driving formwork are different.
Another object of the present invention is to provide a cement-based thin-walled driving formwork that is thin-walled, lightweight, and can be constructed satisfactorily even at small and medium-sized sites using a small crane.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention has a thickness of 20 ± l.
The first member for configuring the left and right formwork consisting of the cement-based secondary member for the driving formwork of O-Zen■ and the first member on the left and right # are joined by butting both sides together and are made of the same material as the 81 member. and a second member for adjusting the formwork width.

In the present invention, the first. The second member preferably has a bending strength of 100 kg 7 cm2 or more in order to withstand external forces during transportation, installation, and concrete pouring, and such a member is manufactured by a normal extrusion method, or A thermosetting melamine resin is mixed with water into a composition containing cement, fine silica, and a water reducing agent, thoroughly stirred with a mixer until it becomes highly viscous, molded by extrusion or pouring, and then heat-treated to obtain a high-viscosity resin. It is preferable to use a high-strength cement-based secondary member. Since such a secondary member has sufficient working strength by itself, there is no need to insert reinforcing bars or wire mesh into the secondary member in advance, which is normally required to maintain strength.

Furthermore, in the present invention, it is possible to arbitrarily form unevenness on the concrete pouring surfaces of the first and second members, and this uneven surface improves the integrity of the formwork and the poured concrete. make it complete. In this way, secondary parts or
(1) It must be solid with no reinforcing bars or wire mesh; (2)
) Since it can be integrally molded with the concrete being poured, this formwork can be regarded as part of the building frame, making it more advantageous than conventional formwork. Furthermore, a structure in which lifting fittings are attached using the unevenness provided on the concrete pouring surface, or a structure in which equipment such as switch boxes is attached using the unevenness provided on the concrete pouring surface. preferable.

Furthermore, a structure may also be adopted in which unevenness is provided on the outer surfaces of the first and second members, and a fired tile or a ready-made tile-like panel having a hook for hooking is attached using the unevenness.

(Function) Since the present invention has the above-described structure, various sizes and shapes can be created by selecting and combining the dimensions of the left and right first members and the second member interposed therebetween according to the specifications of the building. Pouring formwork can be constructed.

Further, by using a cement-based secondary member having a bending strength of 100 kg/cm or more, the thickness of the first and second members can be easily set to the above-mentioned dimensions,
In addition, a thermosetting melamine resin is mixed with water into a composition containing cement, fine silica, and a water reducing agent, thoroughly stirred with a mixer until it becomes highly viscous, molded by extrusion or pouring, and obtained by heat treatment. By using a high-strength cement-based secondary member, the above-mentioned bending strength can be easily obtained.

Furthermore, in the present invention, the bonding strength between the members and the concrete can be increased by forming irregularities on the concrete pouring surfaces of the first and second members.

Furthermore, by using a structure in which lifting fittings are attached using the unevenness provided on the concrete pouring surface, the adhesion between the formwork and the concrete is improved. By utilizing the unevenness provided on the concrete pouring surface to attach equipment such as switch boxes, there is no need to process formwork.

Furthermore, the first. By providing unevenness on the outer surface of the second member and using the unevenness to attach a fired tile or ready-made tile-like panel with a hook for hooking, it is possible to prevent the tile from falling.

(Example) Fig. 1 is a plan view showing an example of the present invention in the case of constructing a column, Fig. 2 is an exploded plan view showing a part thereof, and Fig. 3 is an exploded plan view showing a part of the construction.
The figure is a perspective view showing the assembled state. In Figs. 1 to 3, 1.2 is a first member constituting the left and right surfaces of the column, 3 is a first member L, and a second member for adjusting the width of the formwork is interposed between the ends of 2 and connected. The first part 1.2 was made by extrusion, and the second part 3 was made by casting.

These members 1 to 3 are made of a hydraulic aerogenous powder such as Portland cement, or an aggregate or other compounding material added to the hydraulic aerogenous powder, as disclosed in JP-A No. 62-182144. During kneading, thermally cross-linked melamine resin is added and mixed with water, thoroughly kneaded until a high viscosity is formed, molded, and heat treated. It is possible to increase the strength by Further, by using an appropriate catalyst, polymerization can be obtained even at temperatures close to room temperature.

Examples of the melamine resin include methylol melamine, methyl etherified melamine resin, etc., and polar groups of these resins include methylol group, methoxy group, methylene ether group, etc. In order to react and polymerize these, the heating temperature is generally 130°C to 180°C.
In order to carry out such a polymerization reaction smoothly, for example, naphthalene sulfinic acid, todecylbenzene J lefonic acid, valatoluene sulfonic acid or amine salt, phosphoric acid, etc. The reaction can be accelerated by adding one or more of phthanol esters of , phthanol esters of tetrachlorostallic acid, and inorganic salts, and polymerization can be appropriately performed by heat treatment at room temperature or above.

Regarding the addition amount of the above-mentioned thermally crosslinkable melamine resin, -
For boat fishing, bending strength can be improved even by about 0.8%, and a preferable increase in strength can be obtained especially when it is 1% or more.The same is true for compressive strength, and the industrially preferable range is 100kg/ It is 3% or more, which makes it easy to obtain a bending effect of cm2 or more. The upper limit is 30%
Even if it is added in excess of 10%, it cannot be expected that the bending strength or compressive strength will increase commensurately with the increase in the amount of fence fat.

In addition, when adding and mixing such melamine resin, if necessary, the molecular weight of the sulfonated melamine resin or other resin may be 8,000 to 200,000. Preferably]0000
A mixture of a melamine resin with a high molecular weight of ~150,000 and a water-soluble melamine resin with a relatively low molecular weight such as methylol melamine, methyl etherified melamine, and variations thereof is used. Melamine resin, which has a high molecular weight, becomes a polymer due to the ionic bond between divalent cations such as calcium in cement and sulfonic acid in melamine resin, and water-soluble melamine resin itself or fills the voids and improves the structure of the molded part. Aim for elaboration. In this case, in order to reduce the unit amount of water, it is preferable to use a water reducing agent such as a formalin condensate of melamine or sodium naphthalene sulfonate.

As compounding agents such as aggregates, those commonly used as fine aggregates such as fine silica have been widely used, and as fiber materials such as carbon fibers that are It is possible to use a material that does not deteriorate in quality, but if a catalyst or the like is used as described above, a material with even lower heat resistance can also be used. Furthermore, a polymer resin such as an acrylic emulsion may be mixed.

In the members 1 to 3 of this embodiment, irregularities are formed on the concrete pouring surface. In this example, an example is shown in which the concave portion 4 is formed as a groove with an enlarged bottom portion, and the convex portion 5 is formed between the concave portions 4 to form unevenness.

The members of the first member 1.2 are formed with joining step portions 1a, 2a, while the second member 3 provided between these members 1, 2 is provided with grooves on both sides that match the step portions 1a, 2a. Stepped portion 3
a, 3b, and the stepped portions 1a, 2a of the first members l, 2.
A metal fitting 6 is embedded in advance in the stepped portion 3 of the second member 3.
By inserting the bolt 8 into the hole 7 formed in a and screwing it into the metal fitting 6, both sides of the second member 3 are connected to the first members l, 2.
join to.

As shown in FIG. 1, two sets of the first member 1.2 and second member 3 formed into a U-shape are combined to hold reinforcing bars 9 or steel frames. They are integrated by a joining fitting 10, and concrete is poured.

With such a combination structure, the first member 1.2 and the second member 3 of various sizes are prepared, and by combining them according to the specifications of the building, the vertical and horizontal dimensions can be adjusted to various sizes. A modified driving formwork is obtained. During construction, metal fixing bands are tightened around the formwork before concrete is poured. In addition, these members 1
By forming unevenness on the concrete pouring surface in step 3, it is firmly integrated with the concrete frame and the bonding strength is increased. Also, in the past, wires were buried in the concrete surface in order to increase the bond strength, but this work is difficult and there is a risk of creating a cross-sectional defect in the part where the wire is embedded. As in this embodiment, by forming irregularities on the concrete casting surfaces of members 1 to 3, embedding wires is not necessary and there is no risk of generation of cross-sectional defects.

FIG. 4 shows an example in which the lifting fitting 11 is attached using the unevenness of the concrete pouring surface. The lifting fitting 11 includes a hook portion 11a, a neck portion 11b into which a nut 12 is screwed, and a tightening plate 1 which is screwed or fixed at the tip.
3, and a lifting fitting 1 between the nut 12 and the tightening plate 13.
The clamping plate 13 is inserted into the groove 4 together with the tip of the threaded portion 11b, and the clamping plate 13 is inserted into the groove 4 together with the tip of the threaded portion 11b, and both sides of the slipping prevention plate 14 are fitted. Hook the bent portion 14a onto the tapered surface 5a on the side surface of the convex portion 5, slide them along the groove 4, turn the nut 12 to press the anti-slip plate 14 against the surface of the convex portion 5, and tighten. The lifting fitting 11 is fixed by pressing the plate 13 against a protrusion 4a provided at the opening of the groove 4.

FIG. 5 shows an example in which an installation equipment 20 such as a switch box or an outlet hook is attached using the unevenness provided on the concrete casting surface of each of the members 1 to 3.
into the opening 21 provided in any of the members 1 to 3,
When removing the equipment 20, the stopper plate 22 is locked to the edge of the opening 21, and the inner end of the mounting screw 23 that penetrates the installer 20 penetrates the slippage prevention plate 24, and the slippage prevention plate 24 is removed. The bent portions 24a on both sides are engaged with the tapered surface 5a of the convex portion 5, and the nut 25 screwed into the mounting screw 23 is turned to press the anti-slip plate 24 onto the surface of the convex portion 5.
! The device 20 is being installed.

6 and 7 show that unevenness is formed not only on the concrete casting surface of members 1 to 3 but also on the outer surface, and formed on the tapered surface 30a of the convex portion 30 on fired tiles or ready-made tile-like panels 31. This is an example in which a hook 31a is used for attachment, and according to this embodiment, a tile or the like 31 can be firmly attached.

FIG. 8 shows another embodiment of the present invention, in which the left and right first members I
A and 2A are combined with a second member 3A provided between them from the outside and bonded together with an adhesive 35 (screws, bolts, or nuts may be used) to integrate them. In this example, the first member IA,
Since a force that is pulled upward and downward in the drawing acts on 2A, the second
Tensile strength is required for members 3A and 2A. On the other hand, in the embodiments shown in FIGS. 1 to 3, stress is concentrated in a part of the L-shaped corner of the first member 1.2 due to concrete pouring, so the bending strength of the members 1 and 2 is reduced. Strength is demonstrated.

FIG. 9 shows an example in which this member is applied to a beam, and the first member 1
．． The width of the second member 3B is narrower than the width of the second member 3B. When constructing this formwork, the reinforcing bars are surrounded by the formwork, the formwork is supported by U-shaped fixed frames, and concrete is poured.

Although the present invention has been described above with reference to Examples, the specific shapes, structures, or mutual combinations of the first and second members, compositions of the members, shapes of unevenness, various metal fittings, etc. It goes without saying that various changes and additions can be made to the above.

(Effects of the Invention) According to claim 1, by selecting and combining the dimensions of the first member and the second member interposed therebetween according to the specifications of the building, it is possible to create cast formworks of various sizes and shapes. Compared to the conventional technology in which U-shaped members were created according to building specifications, the number of types of formwork can be reduced, manufacturing equipment can be simplified, and it is advantageous in terms of management. Become.

In addition, since the individual members can be made smaller, it is possible to manufacture them by extrusion molding, which facilitates manufacturing and reduces costs. In addition, since it is thin, it is lightweight and can be installed even with a small crane, making it suitable for small and medium-sized sites.

According to claim 2, the bending strength of the member is 1
By using a material having a weight of 0.00 kg/cm2 or more, the thickness of the member can be easily set to the above-mentioned dimensions, and a thinner and stronger product can be easily obtained.

According to claim 3, the bending strength and compressive strength are 3 to 4 in the conventional
Formwork members with twice the strength can be easily obtained.

According to claim 4, by forming an uneven structure on the concrete pouring surface of the member, the bonding strength between the formwork and concrete is increased, and the formwork and concrete are made into a strong integrated product. Therefore, the formwork can be included as part of the building when calculating the strength of the building.

According to claim 5, the lifting metal fittings improve adhesion between the formwork and concrete, and eliminate or reduce the need for processing the formwork for attaching the lifting metal fittings.

According to claim 6, the uneven portions can be used effectively, and machining operations for attaching equipment are unnecessary or reduced.

According to claim 7, the structure in which fired tiles or the like are hooked onto the convex portion increases the bonding strength of the tiles or the like and prevents the tiles from falling.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing an embodiment of the formwork according to the present invention for corporate use, Fig. 2 is an exploded plan view showing a part of the embodiment, and Fig. 3 is the same as that of Fig. 2. A perspective view, FIG. 4 is a plan view showing an example of how the hanging fittings are mounted in this embodiment, FIG. 5 is a plan view showing an example of how the equipment is mounted in this embodiment, and FIG. A perspective view of a member showing another embodiment,
FIG. 7 is a partially enlarged plan view of FIG. 6, and FIGS. 8 and 9 are a plan view and a side view, respectively, showing other embodiments of the present invention. l, IA, 2.2A: @1 member, 3.3A, 3B/2nd
Member, 4: Groove (recess), 5.30: Convex portion, 6: Metal fitting, 8
: Bolt, 10: Connecting metal fittings, ll: Lifting metal fittings, 20
: Equipment, 31: Tiles, etc., 31a: Hanging nails

Claims (1)

[Claims] 1. Left and right first members for forming the left and right forms made of cement-based secondary members for driving formwork with a thickness of 20 mm ± 10 mm, and the left and right first members are butted on both sides and joined together. and a second member for adjusting the width of the form made of the same material as the first member. 2. The cement-based thin-walled formwork according to claim 1, wherein the first and second members have a bending strength of 100 kg/cm^2 or more. 3. In claim 1 or 2, a thermosetting melamine resin is mixed with water into a composition containing cement, fine silica, and a water reducing agent, sufficiently stirred with a mixer until high viscosity is generated, and then extruded or poured. 1. A cement-based thin-walled casting form, characterized in that a high-strength cement-based secondary member obtained by molding and heat treatment is used as the first and second members. 4. In any one of claims 1 to 3, the first,
A cement-based thin-walled pouring form, characterized in that the second member does not contain reinforcing bars, wire mesh, etc., and has unevenness formed on the concrete pouring surface. 5. The cement-based thin-walled pouring formwork according to any one of claims 1 to 4, characterized in that a lifting fitting is attached by utilizing the unevenness provided on the concrete pouring surface. 6. The cement-based thin-walled pouring formwork according to any one of claims 1 to 4, characterized in that equipment such as a switch box or an outlet box is attached using the unevenness provided on the concrete pouring surface. 7. In any one of claims 1 to 6, the first and second
A cement-based thin-walled driving form, characterized in that the outer surface of the member is provided with irregularities, and the fired tiles or ready-made tile-like panels having hooking claws are attached using the irregularities.