JP3188565B2 - Method for manufacturing PC product that can be immediately removed from mold - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a PC which can be immediately removed from a mold.
It relates to a method of manufacturing a product.

[0002]

2. Description of the Related Art Conventionally, when forming a PC (precast concrete) product, for example, a hollow product such as a concrete pipe or a PC column formwork for construction, it is necessary to use one of these PC products.
After using the inner and outer forms that have a shape along the outside, and arranging these inner and outer forms substantially concentrically, concrete is poured into the space between the two forms. It demolds when it is solidified or cured.

In recent years, in order to improve the manufacturing efficiency of the PC product, Japanese Patent Publication No. Hei 1-15361 (B28B1) has been proposed.
/ 08), a mold for molding is filled with zero-slump concrete, placed on a shaking table, and further pressed to speed up solidification of the concrete, thereby enabling immediate demolding. Proposed.

[0004]

As described above, as a method for immediately removing a concrete product from a concrete product, a method using vibration and pressure is conventionally used. However, a cement product which can be applied because special manufacturing equipment is required. However, its applicability to the production of precast concrete members for general construction was significantly lacking.

[0005] Therefore, an object of the present invention is to solve the above-mentioned problems and to provide a P-type which can be immediately demolded without requiring special manufacturing equipment.
It is to provide a method for manufacturing a C product.

[0006]

In order to achieve the above-mentioned object, a method for producing a PC product which can be immediately demolded according to the present invention is characterized in that a water-absorbing polymer which does not become a gel even when absorbing water and maintains an independent form is absorbed in advance. This water-absorbing polymer, cement, aggregate, and admixture are mixed and vibrated in a mold, and then the vibration is stopped, and the water-absorbing polymer absorbs water and is released (claim). Item 1).

If the amount of water is insufficient at the time of the vibration, water is added (claim 2).

[0008] The water-absorbing polymer may be fine or fibrous.

[0009]

[Function] Examples of the special water-absorbing polymer that does not become a gel state even when absorbing water and maintain an independent form include PQ polymer (trade name) of Osaka Organic Chemicals Co., Ltd. and Lanseal (trade name) of Toyobo Co., Ltd. There is. These special water-absorbing polymers are different from conventionally marketed water-absorbing polymers in that no gelation occurs and excellent fluidity is maintained. PQ
The polymer is in the form of fine particles, and the fine particles have a “snow powder” appearance, are stable for a long time, and have fluidity. Put simply, it can be said that water is powdered. Lanseal is in fibrous form and exhibits similar properties.

[0010] Therefore, when the special water-absorbing polymer is made to absorb water in advance, the water-absorbing polymer is mixed with cement, aggregate, and admixture, and the mixture is vibrated in a mold, the water-absorbing polymer absorbs water during vibration. The water leaches out and the concrete becomes workable. Thereafter, when the vibration is stopped, the polymer absorbs water again, so that sufficient demolding strength is obtained in the concrete, and thus the reabsorption of the polymer exerted by the polymer is achieved.
The hardening of the concrete is promoted by the water action, and the concrete can be immediately removed. If the amount of water is insufficient at the time of excitation, add an appropriate amount of water.

As the vibration means, a rod-shaped vibrator,
A normal vibration device such as a shaking table can be applied.

[0012] In accordance with the present invention as described above, by using a special water-absorbing polymers, even without relying on a special production method, pressurized
Stop the vibration and let the water-absorbing polymer absorb water again.
What readily immediately de-concrete products using conventional vibration device will be able to manufacture.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the accompanying drawings. In this embodiment, an example is shown in which the PC frame 12 for pillars of building materials shown in FIG. 6 is manufactured using the PC product forming frame 10 shown in FIG.

As shown in FIG. 1, the molding frame 10 includes an inner frame 14 and an outer frame 16, and these inner and outer frames 1 are provided.
4 and 16 are fitted and arranged coaxially, and concrete 40 is cast from the hopper 20 into the space 18 formed between them.

The concrete 40 is, to be precise, a mixture of a special water-absorbing polymer, which is kept in an independent form without being gelled even when absorbing water, and a mixture of cement, aggregate, and admixture. Become. As a special water-absorbing polymer,
Here, PQ polymer (trade name) of Osaka Organic Chemical Co., Ltd.
Was used. This special water-absorbing polymer is characterized in that unlike a conventionally commercially available water-absorbing polymer, gelation does not occur and the polymer becomes fine particles having excellent fluidity. Of course, Lanseal (trade name) of Toyobo Co., Ltd. may be used.

Vibration is applied to the outer mold frame 16 by a vibrator 22. During the vibration, as shown in FIG. Becomes workable and is compacted by additional vibration. At the same time, the pressing machine 24 is lowered to apply a pressing force to the concrete, whereby the concrete is pressurized compactly and the solidification of the concrete is promoted.
If the amount of water is insufficient at the time of excitation, add an appropriate amount of water.

Thereafter, when the vibration is stopped, as shown in FIG. 2B, the water-absorbing polymer 41 absorbs water again, so that sufficient demolding strength is obtained for the concrete, and the concrete can be immediately removed. That is, the inner and outer molds 14, 16 after the suspension of the vibration
Is removed by pulling it upward.

In the case of this embodiment, the inner mold 14 is
Has a rectangular cross section as shown in
It is formed into a rigid body by hard rubber or FRP (fiber reinforced resin). 5 is formed on the forming surface 14a of the inner mold 14.
The longitudinal direction of the inner frame 14 (vertical direction in the figure), that is, the inner frame 14 corresponds to the mounting position of an anchor bar 38 described later protruding from the inner side surface of the pillar PC frame 12 shown in FIG. A plurality of continuous grooves 30, 30,... Are formed over the entire length in the demolding direction.

The openings of the continuous grooves 30, 30,... Are closed by rubber seals 32, 32,. A sealing slit 34 is formed in the rubber seal 32.
Are formed, and the anchor streaks 38 are sandwiched between the joining surfaces of the sealing slits 34.
In addition, the said sealing slit 34 means that the opposing sides of which the slit was opened are each sealed in a liquid-tight manner.
Further, the sealing slits 34 are provided with the anchor streaks 38.
The small holes 34a may be formed at the positions where is set.

By the way, the column PC frame 12 is shown in FIG.
As shown in FIG. 5, the inner and outer molds 14, 16 are formed as hollow bodies having a rectangular cross section. The pillar PC mold 12 has a vertical streak 36a and a hoop streak as shown in FIG. 3
6b is buried. Reinforcing bar 3
6 is housed in a space 18 between the inner and outer forms 14 and 16 before concrete is poured.

A large number of anchor bars 38, 38... As projections bent in a substantially U-shape are fixed to the hoop bars 36b of the reinforcing bar cage 36 by welding or the like. The distal end portions of the anchor bars 38 project toward the inside of the reinforcing bar cage 36. When the pillar PC frame 12 is completed, it protrudes from the inner surface of the pillar PC frame 12 as shown in FIG. You.

In short, in the forming mold 10 of the present embodiment, the continuous groove 30 is formed on the molding surface 14a of the inner mold 14, and the opening of the continuous groove 30 is formed with the sealing slit 34. Closed by rubber seal 32, inner and outer mold 1
4 and 16 are arranged, and a reinforcing bar cage 36 is provided between them.
4, the distal end of the anchor bar 38 protruding inside the reinforcing bar cage 36 is inserted into the sealing slit 34 and placed in the continuous groove 30 as shown in FIG. At this time, since the sealing slit 34 is formed by the elastic seal 32, both sides of the sealing slit 34 are deformed along the outside of the inserted anchor streaks 38, and the inserted portions of the anchor streaks 38 are substantially closed. Is held.

Then, the concrete 40 mixed with the above-mentioned water-absorbing polymer 41 is poured into the space 18 between the inner and outer mold frames 14 and 16 in a state where the above-mentioned reinforcing cage 36 is arranged, so that the reinforcing cage 36 is provided. Is buried in the cast concrete and tightened and solidified immediately after the suspension of vibration.
Accordingly, the solidification of the concrete is quickly achieved in combination with the action of the vibrator 22 and the pressurizer 26, and the inner and outer molds 14, 16 are immediately lifted up and removed from the mold. At the time of removing the mold, the anchor streaks 38 move relative to the continuous groove 30 while sequentially pushing and opening the sealing slits 34, and the inner and outer mold frames 1 remain with the anchor streaks 38 remaining.
4, 16 can be demoulded.

As shown in FIG. 6, the inner and outer molds 1
PC formwork 12 for pillars obtained by immediate demolding of 4, 16
Since the anchor bars 38 protrude from the inner surface of the pillar, the bondability with post-cast concrete which is cast inside the pillar PC form 12 at the site is remarkably improved. The strength of the reinforced concrete constructed using the PC formwork 12 can be greatly increased.

[0025]

In summary, according to the present invention, by using a water-absorbing polymer, it is possible to use a water-absorbing polymer without using a special production method.
Stop the vibration and let the water-absorbing polymer absorb water again
Therefore, a concrete removal product can be easily manufactured immediately using a normal vibration device.

[Brief description of the drawings]

FIG. 1 is a schematic view showing one process according to an embodiment of a method for manufacturing a PC product of the present invention.

FIG. 2 is a schematic diagram showing the function of a water-absorbing polymer during and after excitation.

FIG. 3 is a diagram showing a P according to an embodiment of the method of manufacturing a PC product of the present invention.
It is a perspective view which shows the inner mold of the mold for molding C products.

FIG. 4 is an enlarged sectional view of a main part showing an inner mold of a PC product forming mold manufactured by one embodiment of the PC product manufacturing method of the present invention.

FIG. 5 is a perspective view showing a PC product manufactured according to one embodiment of the method for manufacturing a PC product of the present invention.

FIG. 6 is a perspective view showing an upper end portion of a PC product manufactured by one embodiment of the PC product manufacturing method according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 PC product molding form 12 Column PC form 14 Inner form 14a Forming surface 16 Outer form 18 Space 20 Hopper 22 Vibrator 24 Pressing machine 30 Continuous groove 32 Rubber seal 34 Sealing slit 34a Small hole 36 Iron cage 36a Vertical streak 36b Hoop streak 38 Anchor streak 40 Concrete 41 Water-absorbing polymer 42 Water

Continuing on the front page (72) Inventor Miki Aoyama 4-640 Shimoseito, Kiyose-shi, Tokyo Inside the Obayashi-gumi Technical Research Institute Co., Ltd. (72) Yoshimasa Hayashi 4-640 Shimoseito, Kiyose-shi, Tokyo, Japan Obayashi-Gumi Technical Research Institute, Inc. 56) References JP-A-3-47703 (JP, A) JP-A-62-198406 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B28B 1/08 B28C 7/00 C04B 28/02

Claims (3)

(57) [Claims] 1. A water-absorbing polymer, which does not become a gel even when absorbing water and keeps an independent form, absorbs water in advance, mixes the water-absorbing polymer, cement, aggregate, and admixture, puts it in a mold, and vibrates. After that , stop applying vibration and absorb water into the water-absorbing polymer.
PC with immediate demolding, characterized in that demolded by water
Product manufacturing method. 2. The method according to claim 1, wherein water is added when the amount of water is insufficient during the vibration. 3. The method for producing a PC product capable of immediate demolding according to claim 1, wherein the water-absorbing polymer is in the form of fine particles or fibers.