JPH0238367B2 - KONKURIITOSEIHINTSURIAGEYOMAISETSUBUZAINOMAISETSUHOHO - Google Patents

Description

[Detailed Description of the Invention] <Industrial Field of Application> The present invention relates to the formation of insertion holes for lifting concrete products and the embedding of buried members for lifting concrete products in which buried members used for reinforcement are buried in formwork. It is about the method.

<Prior art> Due to the special nature of products that use formwork, it is difficult to provide a locking part on the outer surface of a concrete product to which a lifting wire or the like can be hung. Workers are often exposed to danger and work efficiency is not improved. Moreover, concrete products that are mass-produced using formwork tend to be larger. In this case, it is extremely useful to prepare lifting holes in advance during the manufacture of concrete products, but when trying to form lifting holes with high precision on the surface that is shielded when formwork is used, The formwork becomes an obstacle. In addition, excessive stress is concentrated only in a part of the lifting hole, and an excessive tensile force, which is the biggest weakness of concrete products, is applied, making the lifting hole easy to damage. If the reinforcing buried member is not buried in the lifting hole in advance, safety will not be maintained against the impact force applied during lifting, and it will also cause injury to the worker. A simple metal pipe or the like is not sufficient as the buried member for lifting; it is a plate-like member that runs along the surface of the concrete product and has an insertion hole with the same diameter as the lifting hole provided in the concrete product. In addition to this insertion hole, other holes, notches, tongue pieces, claw pieces, protrusions, unevenness, etc. are formed on the plate-shaped body to expand the holding area in order to sufficiently preserve the concrete in the concrete product. Buried parts are used. However, this lifting buried member made of a plate-like body cannot be used for heavy, large-scale concrete products because the stress is applied only to the insertion hole of the thin plate-like body, which supports the entire weight and impact force of the concrete product. For this reason, the present inventors first distributed and reduced the stress applied to the plate by coaxially inserting and fixing a short metal pipe into the insertion part of the plate as a buried member for lifting. Therefore, we have devised a buried lifting member that has an extremely high safety factor and will not break even if a force greater than the force that would cause the concrete product to break is applied. by the way,
The method that has been widely used for burying these materials for lifting is to bury tapered protruding rods with a length longer than the wall thickness of the concrete product, horizontally between the outer and inner plates of the formwork. The buried member is secured by inserting it through the through hole drilled opposite the position, and then through the insertion hole provided in the buried member. It is done by twisting.

When using this burying method, the protruding rods are tapered, and even if a sufficient amount of mold release agent is applied in advance, it is difficult to pull out the protruding rods after the concrete hardens, and it is time consuming. There are drawbacks such as the edges of the edges chipping off. Further, since the protruding rod has a taper, only the formwork and buried objects that match this taper can be used, and many types of buried objects must always be kept in stock, resulting in a lot of waste. Furthermore, the protruding rods have the disadvantage that they loosen and easily come off when compacting the cement by subjecting the formwork to severe vibrations, allowing cement to leak out from the protruding rods. Moreover, these protruding rods cannot withstand repeated use and are difficult to standardize, requiring spare protruding rods for a large number of products.Furthermore, molded concrete products have transparent holes for lifting. Since holes are formed, water leakage may occur in products such as U-shaped grooves, which is undesirable. When using this method of burying a buried member using a protruding rod, it is impossible to adjust the depth of the lifting hole and provide a blind hole with high positional accuracy. Further, when a large number of lifting holes are provided, there are various practical difficulties, such as a decrease in working efficiency and gradual deformation of the protruding rod due to the pressure during cement injection.

In addition to this burying method, there is also a fastener fixing method in which a hole is formed in a concrete product and a fastener such as a concrete anchor or anchor bolt is inserted and fixed, but this method requires precision in the drilling position and the complexity of the process. It is difficult to adopt due to the cost of the locking fittings and the cost of the locking fittings, and it lacks versatility.

Furthermore, as another method for burying a buried member, a method for burying a buried member for lifting concrete products is generally known as disclosed in Japanese Patent Publication No. 57-31970. However, in this embedding method, after the concrete hardens, the locking fixture comes into close contact with the solidified concrete, making it extremely difficult to remove the locking fixture. In other words, the above-mentioned special public service Sho 57-31970
This is because, as shown in FIG. 2 of the publication, the area of close contact between the locking fixture and the concrete is wide and the area becomes evacuated, so that a large stress is required to rotate and pull out the locking fixture. Therefore, in this embedding method, the width of the nut fixed to the outside of the outer form is made extremely wide, and the threaded width of the female threaded part of this nut and the male threaded part of the locking fixture that is screwed into this female threaded part is made wide. This is what must be done. This is because the locking fixture must be forcibly pulled out by the screw rotation force. However, in a concrete product construction site, it is difficult to secure a larger space outside the outer formwork, which is not preferable in terms of work layout. In addition, the screwing and rotating operation performed to pull out the locking fixture requires a great deal of effort, which poses a problem in that the construction work is time-consuming.

<Purpose of the Invention> Thus, the present invention has been devised to solve these conventional drawbacks and problems, and it is possible to bury buried members with high precision and ease, and to easily support the concrete after it hardens. It is an object of the present invention to provide a method for burying a buried member for lifting a concrete product, which allows the member (locking fixture) to be extracted and does not require a large space outside the outer formwork.

<Structure of the Invention> The method of burying a buried member for lifting a concrete product according to the present invention includes an inner formwork and an outer formwork having a guide member having a hole communicating with a through hole drilled in the outer formwork attached to the outside. and a cylindrical pipe having a substantially disc-shaped locking plate having a plurality of anchor parts, and an insertion hole fixed to the locking plate by penetrating the locking plate at a substantially right angle. Along with arranging buried parts,
A support member consisting of a pair of support member units is inserted into the formwork from the outside through the holes and through-holes, this support member is further inserted into the buried member, and then a wedge-shaped support member is inserted through the guide member. The support member is fixed with a stopper, and the buried member into which the support member is inserted is fixed to the outer formwork. Then, both formworks are filled with cement milk and solidified, and after the cement milk has solidified, the wedge-shaped This is accomplished by pulling out the fasteners, pulling out the pair of member units constituting the supporting member, and then removing the formwork and taking out the concrete product in which the buried members are buried.

<Example> The present invention will be described below based on an example shown in the drawings.

To form a U-shaped groove molding frame, an inner frame 1 having an inverted U-shaped cross section is placed and fixed on a horizontal substrate. Next, closing plates are provided before and after this inner formwork 1. Further, outer forms 2, 2 having the same length as the inner form 1 are installed in the left and right direction of the inner form 1, separated by the thickness of the side wall of the U-shaped groove.

By the way, for each of the outer forms 2, 2, through-holes 3, 3 are bored at the locations where a hole for lifting is required, and a mounting hole 4 communicating with the above-mentioned through-holes 3 is provided on the outside of the outer form 2. The guide member 5 having the structure is fixed.

However, between the inner formwork 1 and the outer formwork 2,
A lifting hole is molded and a reinforcing buried member 6 is placed in advance.

Here, the embedded member 6 has a substantially disk shape, and has a locking plate 8 having a plurality of anchor portions 7 formed by cutting out it.
A cylindrical pipe 10 having an insertion hole 9 inside is fixed to the locking plate 8 by penetrating it at a substantially right angle.
It is composed of

By the way, in the drawings, reference numeral 11 indicates a support member.
The support member 11 includes a pair of support member units 12,
It consists of 12. This support member unit 12 includes an elongated base 13 having a substantially semicircular cross section and a rising portion 14 rising upward from the tip of the base 13.
It is made up of. A substantially cylindrical support member 11 is constructed by overlapping the pair of support member units 12, 12.

Then, this support member 11 is inserted from the outside through the attachment hole 3 of the guide member 5 and inserted between the formworks 1 and 2, and then the cylindrical pipe 1 of the buried member 6 is inserted.
Insert within 0. At this time, the cylindrical pipe 10
It is preferable that the tip of the mold is attached to the inner surface of the outer formwork 2 as shown in FIG. After that, insert the wedge-shaped stopper 15 through the guide member 5,
It fits into the fitting grooves 16, 16 formed in the support member units 12, 12. Then, the pair of supporting member units 12, 12 are firmly attached to the mounting hole 4 of the guide member 5 and the insertion hole 9 of the cylindrical pipe 10 due to the wedge effect of the wedge-shaped fastener 15, thereby fixing the embedded member 6 to the outer mold. This means that it can be fixed to frame 2.

Next, from this state, cement milk 17 is filled between the molds 1 and 2 and solidified. After the cement milk 17 has solidified, the wedge-shaped stopper 15 is pulled out from the guide member 5. Then, the wedge effect is removed from the pair of supporting member units 12, 12, and the mounting hole 4 of the guide member 5 and the cylindrical pipe are removed. It is in a loosely fitted state within the insertion portion 9 of 10.

In addition, outside air is introduced through the gap into the insertion hole 9 of the cylindrical pipe 10 which is in a vacuum state, removing the adsorption effect caused by the vacuum state and making it easy to extract.

Pull out the metal fitting from that state and remove it from the support member unit 12.
14, and pull it out to the outside. Therefore, each unit shall be extracted separately.

After the above, the outer pole frame 2 and the inner frame 1 are demolded to complete the production of the U-shaped groove in which the embedding member 6 is embedded.

The present invention can be used to embed a buried member in any type of concrete product, but it is particularly suitable for products that have through-holes that make it difficult or complicated to fill with cement. Furthermore, the present invention can be similarly used not only for concrete products but also for other types of heavy products such as plaster that are hardened using formwork.

<Effects of the Invention> Thus, the present invention has the above configuration, and the method of burying a buried member for lifting a concrete product according to the present invention allows the lifting hole to penetrate through the wall thickness of the concrete product as when using a protruding rod. Since there is no need to form a through hole, a blind hole-like lifting hole can be formed, and water leakage will not occur even in a concrete U-shaped groove. Moreover, U
There are no holes visible on the inner surface of the groove, which is smooth and beautiful, and there is no chipping around the lifting hole.
There is no problem with the strength of the resulting product.

In addition, very inexpensive members such as supporting members and buried members can be used, and the cement milk can withstand repeated use many times without leaking.

Furthermore, the support member can be fixed quickly and reliably to the guide member using the wedge-shaped fastener, and the base of the support member unit is difficult to move in any direction, such as up and down, left and right, and front and back, and is protected from severe vibrations. The fixed position does not change even when buried, making it possible to bury with extremely high precision.

In addition, when removing the support member after concrete milk solidifies, the support member can be easily removed by pulling out the wedge-shaped retaining metal fittings and pulling out each support member unit. This provides excellent effects such as not requiring a large space for extracting the support member.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway perspective view showing the present invention in use, FIG. 2 is a sectional view thereof, and FIGS. 3a and 3b are a front view and a side view showing a pair of support member units. 1...Inner formwork, 2...Outer formwork, 3...Through hole, 4
... Mounting hole, 5 ... Guide member, 6 ... Buried member, 7 ... Anchor part, 8 ... Locking plate, 9 ... Insertion hole part, 10 ... Cylindrical pipe, 11 ... Support member , 12... support member unit, 13... base,
14... Rising part, 15... Wedge-shaped stopper,
16...Inset groove, 17...Cement milk.

Claims (1)

[Claims] 1 Between the inner formwork and the outer formwork to which a guide member having a hole that communicates with a through hole drilled in the outer formwork is attached to the outside, an engagement member having a substantially disk shape and having a plurality of anchor parts is provided. A stop plate and an embedded member made of a cylindrical pipe having an insertion hole that penetrates the stop plate at a substantially right angle and is fixed are provided, and a support member made of a pair of support member units is inserted into the hole from the outside. The supporting member is inserted into the formwork by penetrating through the guide member and the through hole, and further inserting this supporting member into the embedded member, and then fixing the supporting member with a wedge-shaped fastener that passes through the guide member. The buried member into which the was inserted is fixed to the outer formwork, and then cement milk is filled into both formworks and allowed to solidify.After the cement milk has solidified,
A buried member for lifting a concrete product characterized in that the wedge-shaped stopper is pulled out, a pair of member units constituting the support member are pulled out, and the formwork is then removed to take out the concrete product in which the buried member is buried. Burying method.