JPH04301407A - Manufacture of reinforced hydraulic molded form - Google Patents

Abstract

PURPOSE:To prevent the generation of deformation such as warpage, and to improve productivity without inverting a top force and a bottom force by supplying the bottom force with a hydraulic material and holding a metal plate for reinforcement to the top force in a molded form, pressing the molded form by the top force and the bottom force and unifying the metal plate for reinforcement and the hydraulic material. CONSTITUTION:Total weight of a hydraulic material is fed to a bottom force, and a top force holding a reinforcing agent is made to abut against the hydraulic material. The hydraulic material and the reinforcing agent are unified by the pressing of the top force and the bottom force while being formed in a specified shaped molded form. A hydraulic material, in which water is added to a material containing cement, sand and reinforced fibers, is exampled as the hydraulic material at that time. A net composed of a metal plate, a gauze, organic fibers or inorganic fibers is exampled as the reinforcing agent.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing reinforced hydraulic molded bodies.

0002

2. Description of the Related Art A floating floor is used in which a floor is placed at a predetermined interval on the upper surface of a slag, etc., and wiring for OA equipment, etc. is installed in the gap between the slag and the floor. As such a floor, one made of GRC (fiber reinforced cement) reinforced with iron plates or wire mesh is known. The following methods are known for manufacturing GRC floors reinforced with iron plates or the like. That is, first, a steel plate reinforcement material is placed on the lower mold, and a hydraulic material made of portland cement, glass fiber, sand, water, etc. is supplied on top of it.
This is a manufacturing method in which the material is then pressed using an upper mold and a lower mold to integrate the hydraulic material and the reinforcing material and form it into a plate shape. This molded body is demolded, placed on a holding plate with the reinforcing material facing downward, and cured.

0003

[Problems to be Solved by the Invention] However, in this manufacturing method, since the reinforcing material is located at the bottom, there is a problem that the upper surface, which dries easily, shrinks more than the lower surface, causing warpage in which the lower surface becomes convex. .

The present invention solves the above-mentioned problems of the prior art, and aims to provide a method for manufacturing a reinforced hydraulic molded body suitable for floating floors, etc., which has excellent productivity and does not cause warping.

[0005]

[Means for Solving the Problems] The present invention supplies the entire amount of hydraulic material to a lower mold, then brings an upper mold holding a reinforcing material into contact with the hydraulic material, and presses the material with the upper mold and lower mold. , a method for manufacturing a reinforced hydraulic molded body in which the hydraulic material and the reinforcing material are integrated and a molded body having a predetermined shape, and the entire amount of the hydraulic material is supplied to a lower mold, and then the reinforcing material is A reinforced hydraulic molded body is placed on the hydraulic material and then pressed by an upper die and a lower mold to integrate the hydraulic material and the reinforcing material and form a molded body in a predetermined shape. Provide manufacturing method.

[0006] Examples of the hydraulic material in the present invention include those containing cement, sand, and reinforcing fibers containing water.

[0007] Examples of this cement include portland cement, a mixture of portland cement, alumina cement, magnesia cement, fly ash, slag, and the like. Among them, Portland cement is preferred from the viewpoint of price, and ordinary Portland cement is particularly preferred.

Examples of sand include natural sand such as river sand, and crushed sand such as silica sand.The particle size of the sand is fine aggregate that is normally used, that is, it passes through a 10 mm mesh sieve, and weighs 85% when passing through a 5 mm mesh sieve. % or more is preferable.

Examples of reinforcing fibers include alkali-resistant glass fibers, polyester fibers, vinylon fibers, glass fibers, and acrylic fibers.

The hydraulic material preferably contains cement, sand, and reinforcing fibers in the following proportions. That is, in terms of weight percentage, the content is 30 to 50% cement, 30 to 60% sand, 0.2 to 3% reinforcing fiber, and 10 to 20% water.

If the cement content is less than 30%, curing is insufficient and the strength is lowered, the reaction rate is slow, curing takes a long time, and productivity is lowered, which is not preferable. On the other hand, if the cement content is more than 50%, the sand content will be relatively small, and shrinkage will be large, warping will easily occur, and the strength will decrease, which is not preferable.

[0012] If the reinforcing fiber is less than 0.2%, it is not preferable because the strength decreases and chipping occurs easily during handling.
If it exceeds 2.0%, the fluidity of the material in the pressing process will deteriorate, resulting in a decrease in productivity, which is not preferable.

If the water/cement ratio is less than 30%, hardening will be insufficient and the strength will decrease, which is undesirable, and if it exceeds 45%, the workability in the pressing process will deteriorate, which is undesirable.

[0014] Substantially the entire amount of the thus prepared hydraulic material required for one molded article is supplied to the concave lower mold.

[0015] The lower mold may be an integral type made of one material, or it may be a split mold made of a plurality of members and divided into each member when the molded product is taken out. Further, examples of the material include iron and stainless steel.

[0016] As the reinforcing material in the present invention, a metal plate,
Examples include wire mesh, organic fiber mesh, and inorganic fiber mesh. Among these, metal plates and wire mesh are preferred because they have high strength and are relatively inexpensive. When using a metal plate, it is preferable to have protrusions on one side by punching or the like so that the protrusions bite into the hydraulic material.

On the other hand, the wire mesh has a mesh size of 15 to 60 mm.
A moderate amount is appropriate. Such metal plates are preferably made of common steel, stainless steel, etc. and have a thickness of about 0.2 to 0.8 mm.

The reinforcing material is held by the upper mold by magnetic force or vacuum suction, descends together with the upper mold, comes into contact with the hydraulic material, and is pressed by the upper mold and the lower mold.

When using a metal plate having protrusions as a reinforcing material, it is held in the upper die with the protrusions facing downward, and is pressed into the hydraulic material.

Instead of holding the reinforcing material in the upper mold, the reinforcing material may be placed on the hydraulic material supplied to the lower mold and pressed.

[0021] Pressure during press is 30 to 80 kg/
The area is about cm2, and the time is about 5 to 20 seconds. If this pressure is less than 30 kg/cm2, problems such as the shape of the molded product differing from the intended shape occur, which is not preferable. If it exceeds 80 kg/cm2, a large pressing device will be required, which is not preferable. Also, the pressing time is 5
If the heating time is less than 2 seconds, it is difficult for the molded product to take the desired shape, which is undesirable. If it exceeds 70 seconds, the productivity decreases, which is not preferred.

[0022] During pressing, in order to improve productivity, it is preferable to squeeze water from the hydraulic material using a vacuum device through communicating holes provided in the mold to remove excess moisture.

[0023] Furthermore, during pressing, the mold and hydraulic material usually do not need to be specially heated and can be manufactured at room temperature with sufficient productivity.

In the molded article thus obtained, the hydraulic material is in an uncured state, and the reinforcing material such as a metal plate is located on the upper surface side.

[0025] The molded body is demolded and placed on a holding plate without inverting the upper and lower surfaces. The molded body is cured while placed on a holding plate, and this curing is usually carried out at 30 to 60°C for 4 to 8 hours in order to increase productivity.

During this curing, the upper surface of the molded body tends to shrink more because the amount of water evaporation is greater than that of the lower surface, but since the reinforcing material is present on the upper surface, the shrinkage is suppressed, and as a result, the lower surface and The amount of contraction is balanced. the result,
Does not cause deformation of the molded body. A steel plate, a stainless steel plate, or the like is used as a holding plate in this curing.

[0027] The thickness of the molded body produced in the present invention can be approximately 5 to 40 mm. Moreover, by providing a pattern on the lower die, a molded article having a pattern can be manufactured.

[0028]

Effects of the Invention According to the present invention, a molded article that does not easily undergo deformation such as warping can be manufactured, and the productivity is also excellent since the upper and lower surfaces are not reversed during the manufacturing process.

Claims (3)

[Claims] Claim 1: The entire amount of the hydraulic material is supplied to the lower die, and then the upper die holding the reinforcing material is brought into contact with the hydraulic material, and the upper die and the lower die are pressed to form the hydraulic material and the reinforcement. A method for manufacturing a reinforced hydraulic molded body by integrating materials and forming a molded body into a predetermined shape. [Claim 2] The entire amount of hydraulic material is supplied to a lower die, a reinforcing material is then placed on the hydraulic material, and the reinforcing material is then pressed by an upper die and a lower die to combine the hydraulic material and the reinforcing material. A method for producing a reinforced hydraulic molded body by integrating the above and forming a molded body into a predetermined shape. 3. The method for producing a reinforced hydraulic molded body according to claim 1, wherein the reinforcing material is a metal plate or a wire mesh.