JPH0444055B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for treating concrete surfaces of buildings, and more particularly to a method suitable for dealing with cracks occurring on the concrete surfaces.

(Prior Art) In general, concrete surfaces that form the floors and walls of buildings develop cracks over a long period of time due to neutralization of the concrete, corrosion of reinforcing bars, vibration, etc. If these cracks are left untreated, There were problems with water entering through the cracks, increasing corrosion of the reinforcing bars, and cracks gradually becoming larger. Therefore, it is desirable to take measures such as filling the crack with repair material while it is still small, but since the crack is so small, it is difficult to detect it with the naked eye, and even if it is found, it is difficult to fill the crack with repair material. was extremely difficult.

(Object of the Invention) The present invention has been made with the aim of solving the above problems.

(Structure of the Invention) The inventor of the present invention has a strong passion for crack treatment in concrete, has conducted numerous studies and experiments, and has finally been able to invent an epoch-making method.

Hereinafter, the processing method of the present invention will be explained in detail based on the drawings.

For example, a mobile shot blasting device 2 projects steel particles such as shot and grit onto a concrete surface 1 that forms the floor of a building. That is, an impeller (not shown) rotatably housed in a casing 3 is rotated at high speed by a motor 4 and moved in the direction of arrow 7 by wheels 5 and 6, thereby reducing particle size from 0.6 to 2.0 mm steel grains are applied to concrete at a projection density (weight of steel grains projected per unit area (m ² ) per unit time (minute)) of 75 to 300 Kg/m ² min and a projection speed of 60 to 90 m/sec. Project onto surface 1 diagonally from above. Here, steel grains with a grain size of 0.6 to 2.0 mm are shot at a projection density of 75 to 300 Kg/m ² min and a projection speed of
Projecting at a speed of 60 to 90 m/sec is effective for roughening the surface of high-grade, high-strength concrete and making cracks appear, and projecting steel particles under these conditions can cause damage due to collisions of steel particles. As a result, the surface of the concrete is scraped and roughened, and the cracks in the concrete are particularly prone to chipping, so they are destroyed by collisions with steel grains, and the cracks are gouged deeply, forming V-shaped grooves.

On the other hand, when projecting under conditions below the above range, it is difficult to roughen the concrete surface, and when projecting under conditions above these ranges, the concrete surface may be destroyed and become highly uneven. I end up. After colliding with the concrete surface 1, the thus-projected steel grains bounce back, pass through a collection cylinder 8, are sucked and collected by a hopper 9, and are moved into a flexible duct 1 that communicates with a dust collector (not shown).
After dust such as concrete powder is suctioned and removed through the filter 2, it is projected again by the impeller. As a result, the concrete surface 1 is roughened and at the same time the base end of the crack 10 is crushed, deforming from the state shown in FIG. 3 to the state shown in FIG. A letter-shaped groove 11 is formed. Therefore, the crack 10 that entered the concrete surface 1
can now be easily detected with the naked eye, and
Repair material can be easily filled into the crack 10 from the V-shaped groove 11. Furthermore, since the concrete surface 1 is in a moderately roughened state, when a surface layer material is applied to the surface, the adhesion becomes strong.

In the above embodiment, the floor surface is treated, but the same effect can be obtained even if the wall surface is treated.

(Effects of the Invention) As is clear from the above explanation, the present invention has a particle size of 0.6 on concrete surfaces with cracks.
～2.0mm steel grains with a projection density of 75～300Kg/ ^m2・
Since the concrete is projected at a speed of 60 to 90 m/sec, it is possible to scrape and break the concrete surface, roughen the concrete surface, and at the same time form a V-shaped groove at the base end of the crack. Along with this, it has become much easier to find cracks and fill them with repair materials, making it possible to repair cracks quickly and efficiently, and also to reduce the roughness of concrete surfaces. This produces excellent effects such as increasing the adhesion of the surface material to the concrete surface.

[Brief explanation of the drawing]

The drawings are explanatory diagrams showing the implementation state of the method of the present invention, and FIG. 1 is a side view, FIG. 2 is a plan view, FIG. 3 is an enlarged view of section A in FIG. 1, and FIG. 4 is an enlarged view of section A in FIG. It is an enlarged view of part B. 1...Concrete surface, 2...Shot blasting device, 10...Crack, 11...V-shaped groove.

Claims (1)

[Claims] 1 Steel particles with a grain size of 0.6 to 2.0 mm are applied to the concrete surface at a projection density of 75 to 300 kg/m ² min and a projection speed.
A method for treating a concrete surface of a building, characterized by roughening the concrete surface and simultaneously forming a V-shaped groove at the base end of the crack by projecting at a speed of 60 to 90 m/sec.