JPH0457830B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a method of crushing brittle objects such as walls and floor slabs of existing reinforced concrete buildings using an expansive crushing agent.

Conventional technology Conventionally, in order to crush walls and floor slabs of existing reinforced concrete buildings, it was common to use hand breakers, jet water using high water pressure, diamond cutters, etc. .

Problems to be Solved by the Invention However, in such conventional construction methods, the hand breaker generates noise and dust, and it is extremely difficult to crush vertically, such as walls, and the crushing efficiency is extremely low. There were some shortcomings. In addition, the jet water crushing method, which utilizes high water pressure, is extremely noisy and uses a large amount of water, which poses problems in water treatment, as well as safety issues due to the use of high pressure. Furthermore, although the crushing method using a diamond cutter is effective for floor slabs,
Not only is it difficult to construct on vertical surfaces such as walls, but a large amount of water is used when cutting with cutters, making it difficult to dispose of sewage, and floor slabs must be cut to the size required for outdoor transport. However, there were drawbacks such as extremely poor crushing efficiency such as requiring long hours of work, and high cost in terms of economy.

Therefore, an object of the present invention is to provide a crushing method for efficiently creating openings in reinforced concrete walls and floors without being constrained by reinforcing bars buried in existing reinforced concrete, in order to eliminate the above-mentioned drawbacks of the conventional methods. It's about doing.

Means for Solving the Problems According to the present invention, the reinforced concrete crushing method is capable of performing a reinforced concrete crushing method on the location of the reinforcing bars buried in reinforced concrete walls or floor slabs that are to be crushed and removed, as investigated by a rebar probe. Holes for filling the expandable crushing agent are drilled at intervals of It is characterized by drilling two or more continuous holes to prevent crack extension, and filling the holes with an expandable crushing agent to create planned openings in reinforced concrete walls and floor slabs. It is said that

Accordingly, the present invention uses the above-mentioned means to fill a hole drilled above the position of the reinforcing bars in reinforced concrete to be crushed and removed with an expansive crushing agent, thereby cutting the reinforcing bars in a predetermined manner. openings can be made in a planned manner.

Figure 1 of the drawings shows the situation in which the reinforced concrete crushing method of the present invention is applied to a reinforced concrete wall, and Figures 2 to 7 show each step of the crushing method in order. .

As shown in the diagram, first, the reinforced concrete wall 1
Alternatively, the openings 10 to be systematically crushed and removed are marked in the floor slab 2, for example by degreasing (FIG. 2). Next, this planned opening 1
The positions of the horizontal and vertical reinforcing bars 3, 4 buried in the reinforced concrete wall 1 or floor slab to be crushed and removed are investigated using a suitable reinforcing bar probe, and the reinforcing bars 3, 4 are Position 4 is marked (Figure 3). In addition, if the reinforcing bars are gauntlet bars (double bars), it is sufficient to search only the position of the reinforcing bars on the surface where the work is to be performed, and there is no need to search for the positions of the reinforcing bars on the back side. This is because the reinforcing bars on the front surface and the reinforcing bars on the back surface are generally in almost the same position, and even if they are slightly shifted, it will have little effect on the crushing effect. Next, in the center of the opening 10 of the reinforced concrete wall 1, where the positions of the reinforcing bars 3 and 4 have been investigated, a suitable diameter, for example, a diameter of 70 to 100 mm, is placed in a line across the entire width to be crushed and removed. Continuous hole 12
is drilled using a core drill to form a free surface 11 (FIG. 4). In particular, in the case of a wall, it should be in a horizontal position. The hole 12 is bored to the full thickness of the wall 1 and is a through hole. If there are already openings such as windows and stairs formed in a concrete building, such openings such as windows and stairs can be suitably used as free surfaces.

Next, when drilling the holes for filling the expandable crushing agent,
Inside the line of the opening 10 marked for planned crushing and removal, and inside the marking line
Encircle with another line 14 at the 100mm position, and this line 14
The position on the reinforcing bar closest to the outermost hole 1
6' position. Then, centering on the free surface 11, the upper and lower parts parallel to the free surface 11 or the left and right positions, and 100 to 400 mm and 400 to 400 mm from the position of the free surface 11.
800mm (average 300, 600mm) on horizontal or transverse reinforcing bars that are parallel to the free surface 11.
Holes 16 with a hole diameter of 36 to 50 mm, standard 40 mm, are drilled in a staggered arrangement to the length of the wall 1 or floor slab to the full thickness of the wall 1 or floor slab using a core drill in a total of 4 rows with hole spacing of 200 to 400 mm. (Figure 5).

Subsequently, holes are similarly drilled in the same manner as described above at positions on the reinforcing bar wires existing outside of the bar and parallel to the free surface 11 up to the range to be crushed and removed. However, the outermost hole 16' is inside the fracture removal line marking the opening 10.
It is located on the inner horizontal and vertical, that is, horizontal and vertical reinforcing bars 3, 4 closest to the line 14 at the 100 mm position, and is particularly preferably on the intersection of the horizontal and vertical reinforcing bars 3, 4 (6th figure). When performing such perforations, in the case of a wall, the perforations should be made slightly downward, while the outermost row of perforations parallel to the free surface should also be made on the line 14 at a position 100 mm inside the fracture removal line of the opening 10. The closest inner reinforcing bar location has the advantage of facilitating subsequent filling operations with expandable crushing agent. Further, it is more preferable that the holes 16 are arranged in a staggered manner.

Furthermore, in order to prevent cracks caused by the expansive crushing agent from occurring outside the opening 10 where the planned crushing and removal is to be performed, in the case of a wall, at the top two corners,
In the case of a floor, use a 70 to 100 mm core drill to drill two or more pieces at the four corners and at a 45° angle inside the line of the opening 10 at the full corner of the opening 10 to be crushed and removed. A continuous hole 15 is drilled.

Once the holes 16, 16' for filling the expandable crushing agent are drilled at a predetermined spacing in this way,
An expandable crushing agent slurry mixed with water or a cartridge-type expandable crushing agent soaked in water is first filled into a total of four rows of holes 16, two rows parallel to the free surface 12, vertically or horizontally. and then after 2 to 5 hours the remaining holes 16, 16' are subsequently filled with a similar expanding disintegrating agent. Incidentally, such an expandable crushing agent may be one that is generally used for crushing rocks and concrete. Furthermore, if the hole for filling is a through hole, plug it with packing tape or cloth on the back side, that is, one side, to prevent the expandable crushing agent from flowing out, and also make sure that air is removed from the opening of the hole to be filled. It is preferable that consideration be given to completely filling the hole by providing a hole or closing the end of the hole using packing tape or rag.

After 16 to 24 hours of filling with such an expansive crushing agent,
Due to the expansion pressure sequentially generated by the hydration reaction of the expansive crushing agent, cracks appear in the reinforced concrete wall 1 or floor slab 2, and the vertical and horizontal reinforcing bars 3 and 4 at the intersection point 16' are cut. Therefore, by hitting this with a medium hammer weighing about 5 to 10 kg, the reinforced concrete can be crushed into pieces the size of a human head.If this is removed, the desired crushing will be completed and the reinforced concrete will be destroyed. Planned crushing removal is possible.

According to the reinforced concrete crushing method of the present invention configured in this way, the position of the reinforcing bars buried in the reinforced concrete walls, floor slabs, etc. to be crushed and removed is investigated in advance using a reinforcing bar probe, and the location of the reinforcing bars buried on the reinforced concrete walls or floor slabs, etc. to be crushed and removed is investigated in advance. A core drill is used to drill holes for filling the expandable crushing agent in order to facilitate crushing with the expandable crushing agent without being constrained by reinforcing steel, and in particular, to make holes 100 mm inside the area to be crushed and removed in a planned manner. The outermost row of expandable crushing agent filling holes are placed on the inner reinforcing bars buried in the closest position, in the upper two corners of the planned fracture area in the case of walls and in the four corners in the case of floor slabs. By installing two or more continuous holes in the corners, the development of cracks caused by the expanding crushing agent can be prevented from extending outside the planned crushing area, and the filling time of the expanding crushing agent can be made closer to the free surface. By distinguishing between the filling holes located in the inner part and the filling holes located outside, and giving a 2 to 5 hour difference between the two, it is easier to generate cracks, and the generation of cracks is concentrated only in the direction of the free surface, thereby reducing noise. It is possible to produce effects such as extremely little generation of dust and dirt, and because it can be crushed into pieces the size of a human head, it can be easily transported.

Therefore, in the method of systematically crushing reinforced concrete walls and floor slabs of the present invention, the core drill is used to prevent noise and dust generated during drilling, and the expansive crushing agent generates a large number of cracks. This is a construction method that allows for easy and systematic crushing and removal by hitting with a medium-sized hammer.
Compared to other conventional construction methods, noise, vibration, dust, flying stones,
Since pollution factors such as dirt are largely eliminated, it can be applied even in residential buildings.

Next, an example of implementing the reinforced concrete crushing method of the present invention will be shown.

Example 1 During construction work in which a 15 cm thick wall of a reinforced concrete building was systematically crushed to create an opening 1800 mm wide and 1400 mm wide, and a door was installed, the part to be crushed was first marked, and the inner part Reinforcement bar probe ``Profometer 3'' detects reinforcing bar arrangement status
(manufactured by Prosecuil, Switzerland) to mark the reinforcing bar positions on the wall surface. Next, use a diamond core drill equipped with a diamond bit with a nominal diameter of 3 inches (outer diameter 77.4 mm, inner diameter 68.4 mm) to drill continuous through holes in a row on the horizontal reinforcing bars in the center of the wall to be crushed. and set the free surface. After that, in order to drill holes for filling the expandable crushing agent, we aimed at horizontal reinforcing bars with a nominal diameter of 11/2 inches ( A diamond core drill equipped with a diamond bit with an outer diameter of 40.0 mm and an inner diameter of 32 mm is used to drill through holes at a hole interval of 30 cm, with the outermost hole being located inside the fracture removal line.
On the reinforcing bar closest to 100mm. Therefore, the outermost hole is at the reinforcing bar position parallel to the fracture plan line, and the inner hole is at the reinforcing bar position either vertically or horizontally. After drilling these holes, two consecutive holes were drilled at the left and right corners of the upper wall using a core drill equipped with a diamond bit with a nominal diameter of 3 inches at an angle of 45° inward from the planned fracture line. . Immediately after drilling these holes, a slurry of the expandable crushing agent "Blystar" (manufactured by Onoda Cement Co., Ltd.) mixed with water was applied to the holes in a total of four rows, two rows each above and below, parallel to the free surface. The hole was filled using a filling device with a rubber hose of approximately 10 cm attached to the bottom of the can. The hole drilled at this time was a through hole, so the end of the hole was plugged with a rag to prevent the slurry from flowing out, and the filling hole was held down with packing tape or a rag to prevent the slurry from flowing out. .
After the completion of filling the four rows of holes with the expandable crushing agent, the holes further drilled on the outside were filled with the expandable crushing agent slurry in the same manner as described above and left to stand.

When we observed the wall surface 16 hours after the final filling work was completed, we found that the main cracks were generated parallel to the free surface, connecting the holes, and the closer to the free surface the wider the crack, with the maximum width growing to about 5 mm. Was. In addition, vertical cracks have occurred in some areas, but the cracks have not extended to the outside of the planned fracture area, and in some cases the cracks have extended to the inside of the two continuous holes drilled in the upper left and right corners. However, no outward progress was observed. After observing this crack, the weight of the head was immediately reduced to 5 kg.
After a moderate hammer blow, the concrete could be removed in 30 minutes. After that, by cutting the exposed reinforcing steel and scraping some concrete around the area, we were able to systematically form an opening for installing the door.

Example 2 In construction work to create a 1,800 mm square opening in the center of a 20 cm thick floor of a reinforced concrete building, we first marked the part to be crushed, and then used the rebar probe ``Profile'' to check the reinforcing bar arrangement inside the part. Ometer (manufactured by Prosecuil, Switzerland) was used to mark the reinforcing bars on the floor, and then the reinforcing bars in the center of the crushed floor were marked with a nominal diameter of 3 1/2 inches (outside diameter 90.8 mm). Using a diamond core drill equipped with a diamond bit with an inner diameter of 81.4 mm, continuous holes were drilled across the entire width of the crushed bed to form a free surface. After that, use the core drill used to set the free surface at the four corners of the fracture bed surface at an angle of 45° inward from the planned fracture line.
Two continuous holes were drilled at the angle of . After that, in order to drill holes for filling the expandable crushing agent, on the left and right reinforcing bars that are parallel to the free surface and located 30 cm, 50 cm, and 80 cm from the reinforcing bars that were cut when setting the free surface, the nominal diameter 11 Through holes were drilled with a hole spacing of 25 cm using a core drill equipped with a /2 inch (outer diameter 40.0 mm, inner diameter 32 mm) diamond bit.
At this time, the outermost hole is inside the planned fracture marking line.
It was placed on the reinforcing bar closest to 100mm. Immediately after this drilling is completed, the expansible crushing agent “Blystar” is applied.
(manufactured by Onoda Cement Co., Ltd.) mixed with water was poured into a total of four rows of holes, two rows each on the left and right parallel to the free surface. At this time, since the drilled hole was a vertical hole and a through hole, care was taken to prevent the slurry from flowing out by plugging the end of the hole to a thickness of about 2 cm using packing tape and rag. Thereafter, after a delay of 3 hours, the holes in the outer row were filled with expandable crushing agent slurry in the same manner and left to stand. When we observed the floor surface 20 hours after the filling work was completed, we found that cracks were running between the holes, and the width of the cracks in the row closest to the free surface, parallel to the free surface, was the largest, reaching about 4 mm. Ta. In addition, the cracks were found only inside the planned fracture, and no extension to the outside was observed. Immediately after this observation, the concrete was easily crushed by hitting it with a medium hammer, and the reinforced concrete was removed in 20 minutes. After that, we were able to systematically form openings by cutting the reinforcing bars and finishing the outer periphery.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a situation in which the reinforced concrete crushing method of the present invention is implemented, and FIGS. 2 to 7 are diagrams sequentially showing the implementation conditions of the reinforced concrete crushing method of the present invention. In the figure, 1...Reinforced concrete wall, 2...Floor slab, 3, 4...Reinforcement bar, 10...Opening, 11
...Free surface, 12, 15, 16, 16'...hole,
14... line.

Claims (1)

[Claims] 1. Investigate and mark the position of reinforcing bars buried in the crushed and removed portion of a reinforced concrete wall or floor slab using a reinforcing bar probe, and mark the locations at required intervals over the locations of the reinforcing bars buried in the crushed and removed portion of the reinforced concrete wall or floor slab. A hole for filling an expandable crushing agent can be bored, a continuous hole can be bored in the center of the crushing and removing part to form a free surface, and at least the corner part 2 of the crushing and removing part can be formed.
Drill two or more continuous holes in the corners to prevent crack extension, and fill the holes with an expandable crushing agent to create planned openings in the reinforced concrete wall or floor slab. A reinforced concrete crushing method characterized by: