JPS62125872A - Static grinding method - 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 Field of the Invention The present invention relates to a method for statically crushing brittle objects such as concrete and rocks.

Conventional technology Conventionally, the method of statically crushing brittle objects such as concrete and rocks is to drill holes in the concrete or rocks, fill the holes with an expanding agent, and use the expansion pressure to crush them. It has been known.

The swelling agent used in this case is mostly composed of calcium oxide. Furthermore, when the swelling agent is in the form of a three-dimensional molded product, the swelling agent is filled into the pores, and then water is injected to cause the calcium oxide in the pores to undergo a hydration reaction with water. A method used was to generate expansion pressure to crush concrete and rocks.

Problems to be Solved by the Invention By the way, if there are cracks in the rock or concrete to be crushed that allow water to leak, the hydration reaction of calcium oxide will not occur because the injected water cannot be retained within the crushing structure. The problem was that it was not enough, and as a result, it was often impossible to crush it.

Means for Solving the Problems The present inventors have completed the present invention as a result of various efforts to solve the above problems.

In other words, this method involves statically crushing a brittle object by utilizing the expansion pressure caused by the hydration reaction of an expansion agent. This is a static crushing method in which the pores are filled with an expanding agent formed by compression molding, and water in which a water-soluble polymer substance is dissolved is injected.

The expanding agent used in the present invention must be formed by compression molding a mixture containing calcium oxide as a main component and alumina cement or (II salt) as a hydration retardant, and the molding volume must be 0.05 to 100m, bulk density 2.0-3.29
/Cm is preferable.

As this molding device, one known to those skilled in the art as a briquette is used. The shape of the molded product is preferably a shape that creates as little space as possible during filling, that is, a shape that allows for closest packing, such as an almond shape.

Furthermore, water-soluble polymer substances that dissolve in water include polyacrylamide, methylcellulose, polyethylene oxide,
Starch, polyvinyl alcohol, etc. are suitable, but polyacrylamide is particularly preferred.

The amount of the water-soluble polymer substance to be added varies depending on its type, but it is appropriate that the apparent viscosity of the aqueous solution is about 50 to 5000CpS, more preferably 500 to 1000CpS.
It is.

Such water-soluble polymer substances dissolve in water and thicken,
Even if there are some cracks in the rock or concrete that forms the crushed structure, there is little chance of water leaking during injection, and sufficient water can be retained in the pores for the hydration reaction of the expanding agent.

However, if the aqueous solution has too high a viscosity, it will be difficult to penetrate into the gaps between the swelling agents, and the hydration reaction will be inhibited.

Referring to the drawings, the state in which rock is crushed by the method of the present invention will be described. A hole is made in a natural crushed stone 1, the expandable molded body 3 is filled in the hole, and then an aqueous solution of a water-soluble polymer substance is poured into the hole. Fill 4. Due to the pressure generated when the swelling agent hydrates and expands, cracks 2 are formed in the natural crushed stone 1 around the holes, which can be easily crushed.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example: When a hole of 65φ x 800#I was dug in a natural crushed stone with a volume of 11, and water was injected into the hole at a rate of 1.5, the entire amount of water leaked out through the cracks.

However, in the pores of this crushed stone, an expandable mixture having the following composition: Calcium oxide 80 parts by weight Alumina cement 20 parts by weight Calcium oxide TWA
Briquettes obtained by mixing 3 parts by weight and compression molding (volume 0.675 cm, bulk density 2.6 C1/
Cm3) was packed in an amount of 3.7 kg at a packing density of 1.4 g/Cm.

After filling the briquettes, a 5% aqueous solution of polyacrylamide was injected at 1.5 kCI.

Five minutes later, the rock split into three pieces.

Comparative Example An experiment was conducted under the same conditions as in the Example except that 1.5 kg of ordinary water was injected instead of the polyacrylamide aqueous solution in the Example, but the rock did not crack at all.

Effects of the Invention As described above, the present invention is capable of sufficiently retaining water in a fractured building frame that would otherwise leak water even if ordinary water was injected into it.

Therefore, according to the present invention, rocks can be reliably crushed using the expanding agent.

[Brief explanation of drawings]

The drawings are detailed illustrations of the invention. 1...Natural crushed stone 2...Cracks 3...Expanding agent

Claims (1)

[Claims] In a method of statically crushing a brittle object using the expansion pressure accompanying the hydration reaction of the expansion agent, an expansion agent formed by compression molding an expansion mixture mainly composed of calcium oxide and a substance that retards its hydration reaction. A static crushing method characterized by filling the holes with water and injecting water in which a water-soluble polymer substance is dissolved.