JP2020165271A - Structure cutting method and cutting device - Google Patents

Abstract

To provide a structure cutting method that can cut a structure by installing a cutting device on a lower face side of the structure and can reduce the possibility of damaging parts, other than that to be cut and removed, which are to be reused.SOLUTION: In a structure cutting method for cutting a structure with a wire saw that uses a cutting device 1 having a wire saw 10, a wire saw drive mechanism, and guide means for guiding the wire saw, a structure is cut by driving the wire saw with the wire saw drive mechanism and the guide means attached to a lower surface 3u of a structure (floor slab 3).SELECTED DRAWING: Figure 3

Description

The present invention relates to a cutting method and the like when cutting a structure using a cutting device provided with a wire saw.

Conventionally, for example, in the construction of renewing a concrete floor slab (hereinafter referred to as a floor slab) as a structure of a bridge, since the existing girder is reused, the old floor slab attached to the upper surface of the girder is cut. It is removed and the new floor slab and girder are joined.
In the demolition work when renewing the floor slab of the bridge, a cutting method is used to cut the portion near the boundary between the floor slab attached to the upper surface of the girder and the upper surface of the girder using a cutting device equipped with a wire saw. Are known.
For example, a method of installing the cutting device on the upper surface of the floor slab, that is, on the upper surface side of the road for cutting (see Patent Document 1), or a method of installing the cutting device on the lower surface side of the floor slab for cutting (see Patent Document 1). (See Patent Document 2) is known.

Japanese Unexamined Patent Publication No. 2018-145797 JP-A-2018-145668

In the cutting method using the cutting device disclosed in Patent Document 1, since the cutting device is installed on the upper surface side of the road for cutting, there is a problem that the road closure period becomes long.
On the other hand, in the cutting method using the cutting device disclosed in Patent Document 2, since the cutting device is installed on the lower surface side of the floor slab to cut, the road closure period can be shortened.
However, in the cutting method of Patent Document 2, since the guide member of the cutting device is attached to the girder via the attachment member, the girder may be damaged.
Further, in the cutting method of Patent Document 2, a through hole is formed between the floor slab and the upper surface of the girder to insert a wire saw and to attach a guide member mounting member to the upper flange of the girder. However, in order to attach the mounting member of the guide member to the girder, it is necessary to form a through hole so that the upper surface of the upper flange of the girder is exposed, and the upper surface of the girder may be damaged when the through hole is formed. There is also sex.
Further, in the cutting method of Patent Document 2, the distance between the wire saw and the upper surface of the upper flange of the girder is only the thickness of the plate forming the upper end portion of the mounting member located on the upper surface of the girder. If the plate thickness is thin, when the wire saw is driven, the wire saw may come into contact with the upper surface of the upper flange of the girder and damage the upper surface of the girder.
As described above, according to the cutting method of Patent Document 2, there is a problem that there is a high possibility that the reused portion such as the girder other than the portion to be cut and removed is damaged.
An object of the present invention is to provide a method for cutting a concrete structure, etc., which can reduce the possibility of damaging a portion to be reused other than a portion to be cut and removed without impairing the utilization around the structure. To do.

The method for cutting a structure according to the present invention is a structure for cutting a structure with a wire saw using a cutting device having a wire saw, a drive mechanism for the wire saw, and a guide means for guiding the wire saw. The cutting method is characterized in that the structure is cut by driving the wire saw with the drive mechanism and the guide means of the wire saw attached to the lower surface of the structure, which impairs the use of the periphery of the structure. It is possible to reduce the possibility of damaging the reused part other than the part to be cut and removed.
Further, since the structure is a floor slab attached to the upper surface of the girder, and the floor slab is to be cut in the vicinity of the boundary between the floor slab and the upper surface of the girder, the floor slab is renewed. In, the use around the floor slab, that is, the use of the road is not impaired, and the possibility of damaging the reused girder can be reduced.
Further, since the cutting target portion is above the splicing plate that connects the girders and the bolt that fixes the splicing plate, it is possible to cut and reuse the splicing plate and the bolt that are obstacles. The possibility of damage to the girder can be reduced.
Further, a roller having a rotatable circumferential surface that contacts the lower surface of the wire saw during the cutting operation is arranged along one end edge in the width direction of the girder, and the roller is cut along the other end edge in the width direction of the girder. Since the pulley that guides the operating wire saw is arranged, the roller and pulley can guide the wire saw to the planned cutting position with high accuracy, improving the cutting accuracy and smoothing the wire saw on the roller. It can be moved and the cutting operation with a wire saw can be performed smoothly.
Further, the cutting device according to the present invention is a cutting device used in the above-described method for cutting a structure, and is a wire saw, a drive mechanism for the wire saw, a guide means for guiding the wire saw, a guide means, and a drive mechanism. It is characterized by being provided with a mounting means for mounting the structure on the lower surface of the structure, so that it is possible to damage the reused part other than the part to be cut and removed without impairing the use around the structure. It is possible to provide a cutting device that can reduce the performance.
Further, it is characterized in that it is provided with a vertical position adjusting mechanism for adjusting the vertical position of the guide means, or that the mounting means is provided with a vertical position adjusting mechanism for adjusting the vertical position of the guide means. , The wire saw can be accurately guided to the planned cutting position, and if there is an obstacle during cutting, the level of the cutting position by the wire saw can be adjusted, so the obstacle can be avoided and the obstacle can be avoided again. The possibility of damage to the parts used can be reduced.
Further, since the guide means is provided with a plurality of pulleys on which the wire saw is hung, the wire saw can be accurately guided to the planned cutting position.
Further, since the rotation center axis of each pulley is configured so as not to protrude upward from the upper surface of the pulley, the pulley can be brought closer to the lower surface of the structure, and the cutting target portion is determined. The effect of increasing the degree of freedom in the setting range can be obtained.
Further, since the guide means is provided with a roller having a rotatable circumferential surface that contacts the lower surface of the wire saw during the cutting operation, the wire saw can be accurately guided to the planned cutting position. As a result, the cutting accuracy is improved, and the wire saw moves smoothly on the roller, so that the cutting operation by the wire saw can be performed smoothly.

A plan view of the cutting device attached to the lower surface of the floor slab as viewed from above the floor slab. A side view of the cutting device attached to the lower surface of the floor slab as viewed from the right side of FIG. The front view of the cutting device attached to the lower surface of the floor slab as viewed from the lower side of FIG. It is a figure which shows the driven pulley, (a) is the sectional view which shows the pulley which provided the rotation center axis by a headless bolt, (b) is the sectional view which shows the pulley which provided the rotation center axis by a headed bolt. It is a figure which shows the attachment means, (a) is the perspective view which shows the 1st attachment member, (b) is the perspective view which shows the 2nd attachment member. An enlarged view of the first mounting member mounted on the lower surface of the floor slab. The side view which shows the other example of the drive side array pulley group. It is a figure which shows the cutting apparatus provided with the guide means composed of a plurality of driven pulleys and drive pulleys arranged so arranged in the cutting direction, (a) is a plan view, (b) is a side view, (c). ) Is the front view. It is a figure which shows the cutting apparatus provided with the guide means which has a roller conveyor, (a) is a plan view, (b) is a perspective view which shows the wire saw which is guided by a roller conveyor. It is a figure which shows the cutting apparatus provided with the guide means which has a roller, (a) is a plan view, (b) is a perspective view which shows the wire saw which is guided by a roller.

Embodiment 1
The method for cutting the structure and the cutting device according to the first embodiment will be described with reference to FIGS. 1 to 6.
Note that FIG. 1 is a plan view of the cutting device attached to the lower surface of the floor slab in the dismantling work when updating the floor slab of the bridge, as viewed from above the floor slab. Devices and girders should be shown by dotted lines, but are shown by solid lines to clearly show the configuration.

The method for cutting the structure according to the first embodiment is, for example, in the dismantling work when renewing the floor slab of the bridge, as shown in FIG. 3, using the cutting device 1 provided with the wire saw 10, the girder 2 When cutting the cutting target portion 3A of the floor slab 3 near the boundary between the reinforced concrete floor slab 3 as a structure attached to the upper surface 2t via a fixing member such as a slip stopper 2K and the upper surface 2t of the girder 2. , The wire saw 10 is driven in a state where the cutting device 1 is attached to the lower surface 3u of the floor slab 3 and the cutting device 1 is supported by the floor slab 3, and the cutting device 1 is driven near the boundary with the upper surface 2t of the girder 2 in the floor slab 3. By cutting a certain part to be cut 3A, the cutting device 1 can be installed on the lower surface 3u side of the floor slab 3 to cut the floor slab 3, and at the part to be reused other than the part to be cut and removed. This is a cutting method that reduces the possibility of damaging a certain girder 2.
The cutting target portion 3A is, for example, the upper surface 2t of the girder 2 in the haunch (tapered) portion of the floor slab 3 formed on the inclined lower surface 3ut that is inclined upward from both ends in the width direction of the upper surface 2t of the girder 2. It is the part near the boundary of.
Further, the lower surface 3u of the floor slab 3 is a lower surface other than the inclined lower surface 3ut of the haunch portion.
In this specification, the width direction is defined as the direction indicated by "W" in FIGS. 1 and 3, and the vertical direction is defined as the direction indicated by "up and down" in FIGS. 2 and 3.
Further, in FIGS. 2 and 3, reference numeral 4 is a workbench such as a scaffolding board.

The cutting device 1 includes a wire saw 10, a guide portion of the wire saw 10, a drive device of the wire saw 10, and an attachment means for attaching the guide portion and the drive mechanism to the lower surface 3u of the floor slab 3.

The wire saw 10 is composed of, for example, an endless annular wire (diamond wire) in which beads in which diamond abrasive grains are embedded are attached at regular intervals.

The cutting device 1 has a through hole 3a formed so that the wire saw 10 penetrates, for example, over one inclined lower surface 3ut and the other inclined lower surface 3ut of the haunch portion which is the cutting target portion 3A of the floor slab 3. The drive pulley 20 is hung on a plurality of driven pulleys to form an endless ring, and the drive pulley 20 moves while rotating to pull the wire saw 10, so that the wire saw 10 is a concrete portion. It is configured to cut into the cutting target site 3A by biting into.

The guide portion of the wire saw 10 includes a guide means and a support means for supporting the guide means.

The guide means includes, for example, a drive pulley 20 and a plurality of driven pulley groups.

As shown in FIGS. 1 and 2, for example, the plurality of driven pulley groups include a cutting-side array pulley group 21 that guides the wire saw 10 in the cutting direction and cutting along the cutting direction that constitutes the circulation path of the wire saw 10. At least two path conversion pulleys 22, 22 provided at the boundary between the side path and the drive side path, and the drive side array pulley group 23 for guiding the wire saw 10 to the drive side are provided.
As shown in FIG. 1, for example, the cutting-side array pulley group 21 is two pulleys arranged at intervals along the extension direction of the upper surface 2t of the girder 2 on both sides in the width direction of the upper surface 2t of the girder 2. That is, it is composed of a total of four driven pulleys 25, 25 ... The number of driven pulleys constituting the cutting-side array pulley group 21 and the drive-side array pulley group 23 may be a plurality.

As shown in FIG. 4A, for example, the plurality of driven pulleys 25, 25 ... Constituting the cutting-side array pulley group 21 can rotate around the rotation center axis 25a and the rotation center axis 25a. The pulley body (rotating body) 25b provided and the bearing 25c incorporated in the center hole of the pulley body 25b so as to be located between the rotation center shaft 25a and the pulley body 25b are provided, and the rotation center shaft 25a is provided. Is fixed to the bracket 25Z.
As shown in FIG. 4A, the driven pulley 25 uses a headless bolt as the rotation center shaft 25a, and the upper end (one end) of the rotation center shaft 25a is above the upper surface 25r of the pulley body 25b. It is configured so that it does not protrude into the. At the upper end (one end) of the rotation center shaft 25a, a female screw portion 25f to which the male screw portion 25e of the low head screw 25d functioning as a bearing retainer is screwed is formed.
The driven pulley 25 is fixed to the support 28 via, for example, the bracket 25Z so that the fixed position can be changed in the extension direction of the support 28 described later. For example, the driven pulley 25 is fixed to the bracket 25Z, and the bracket 25Z is fixed to the support 28 using screws or the like (see FIG. 6) so that the fixing position can be changed in the extension direction of the support 28. ..

That is, by penetrating the other end side of the rotation center shaft 25a through the through hole 25g formed in the bracket 25Z, inserting the washer 25h into the screw portion on the other end side of the rotation center shaft 25a, and fastening the nut 25i. , The rotation center shaft 25a is fixed to the bracket 25Z. Then, after inserting the spacer 25j into the rotation center shaft 25a from one end side of the rotation center shaft 25a, the pulley body 25b in which the bearing 25c is incorporated is inserted, and then the low head is inserted into one end (upper end) of the rotation center shaft 25a. By fastening the screw 25d, the driven pulley 25 fixed to the bracket 25Z is configured.
A guide groove 25m for inserting the wire saw 10 and circulating the wire saw 10 is formed on the circular outer peripheral surface of the pulley body 25b.
Further, a tool insertion hole 25k for inserting a tool such as a hexagon wrench to rotate the low head screw 25d is formed in the center of the upper surface of the low head screw 25d of the low head screw 25d.

As the plurality of driven pulleys 27, 27 ... Constituting the drive-side array pulley group 23, and the path conversion pulley 22, a pulley having a normal configuration may be used.
That is, as the driven pulleys 27 and 22, for example, as shown in FIG. 4B, a pulley having a configuration in which a headed bolt 27a is used as the rotation center axis may be used.
That is, the driven pulleys 27 and 22 have bolts 27a penetrated through the center hole of the bearing retainer 27c, the bearing hole in the pulley body 25b in which the bearing 25c is incorporated, the center hole of the spacer 25j, and the through hole 25g of the bracket 25Z. After that, the bearing 25h is inserted into the tip side of the bolt 27a and the nut 25i is fastened.
As the plurality of driven pulleys 27, 27 ... Constituting the drive side array pulley group 23 and the path conversion pulley 22, the pulleys having the configuration shown in FIG. 4A may be used.

The height dimension h1 of the low head 25t of the low head screw 25d of the driven pulley 25 (see FIG. 4A) is the height dimension of the head 27b of the headed bolt 27a constituting the rotation center axis of the pulleys 27 and 22. It is smaller than h2 (see FIG. 4B).
That is, each of the plurality of driven pulleys 25, 25 ... Constituting the cutting side array pulley group 21 is configured so that the amount of protrusion upward from the upper surface 25r of the pulley main body 25b is smaller than that of the pulleys 27, 22. There is.

The support means are a first support device for supporting the driven pulleys 25, 25 ... Constituting the cutting side array pulley group 21, and two path conversions of the driven pulleys 27, 27 ... A second support device for supporting the drive pulleys 22 and 22, the drive pulley 20, and the drive device of the wire saw 10 and a third support device for supporting the path conversion pulley 22 are provided.

As shown in FIG. 1, for example, the first support device is composed of a plurality of supports 28, 28 provided so as to extend along the lower surface 3u of the floor slab 3 below the lower surface 3u of the floor slab 3. Will be done.
As shown in FIG. 2, for example, the second support device includes a plurality of supports 28, 28 provided so as to extend along the lower surface 3u of the floor slab 3 below the lower surface 3u of the floor slab 3. It is composed of a support frame 289 in which a plurality of supports 29 and 29 provided so as to extend in the vertical direction are combined.
The third support device is composed of a support 30 provided so as to be movable in the vertical direction with respect to the support 29, for example, as shown in FIGS. 3 and 5 (b).
The supports 28, 29, and 30 are formed of, for example, a long material such as a metal tube having a rectangular cross section.

The drive device of the wire saw 10 includes a drive pulley 20 and a drive control device 32 that rotates the drive pulley 20 and linearly reciprocates the drive pulley 20.
The drive control device 32 rotatably supports, for example, a pulley rotation motor (not shown) as a rotation drive source connected to the rotation center shaft 20C of the drive pulley 20, and the rotation center shaft 20C of the drive pulley 20. A linear movement mechanism 33 for reciprocating the bearing and the drive pulley 20 in the vertical direction along the support 29 is provided.

The linear movement mechanism 33 includes, for example, a rack (not shown) provided on the support 29 side, a pinion (not shown) provided on the housing side and meshing with the rack, and a pulley (puller) moving as a drive source for rotating the pinion. A motor (for example, a hydraulic motor) and a control circuit for the pulley moving motor are provided.
That is, by rotating the pinion, the drive pulley 20 can reciprocate in the extension direction of the rack, that is, in the vertical extension direction of the support 29.

The mounting means for mounting the guide portion and the drive mechanism on the lower surface 3u of the floor slab 3 is a plurality of first mounting means for mounting the plurality of supports 28, 28 constituting the first support device on the lower surface 3u of the floor slab 3. Mounting members 41, 41 ..., a support frame 289 constituting the second support device, and a plurality of second mounting members 42 for mounting the support 30 constituting the third support device on the lower surface 3u of the floor slab 3. To be equipped.

As shown in FIGS. 5A and 6, for example, the first mounting member 41 includes a floor-side mounting member 43 that is mounted on the lower surface 3u of the floor slab 3 with anchor bolts 40 or the like, and a support that is mounted on the support 28. The support body side mounting member 44 is provided with the body side mounting member 44, and the support body side mounting member 44 is mounted so as to be movable in the vertical direction with respect to the vertical extension plate 43b of the floor side mounting member 43. The structure is provided with a vertical position adjusting mechanism that can adjust the vertical position of the driven pulley 25. It is configured.
That is, the first mounting member 41 has a configuration in which the driven pulley 25 as a guide means is fixed to the lower surface 3u of the floor slab 3 and is provided with a vertical position adjusting mechanism for adjusting the vertical position of the driven pulley 25. There is.

The floor-side mounting member 43 includes a fixing plate 43a fixed to the lower surface 3u of the floor slab 3 with anchor bolts 40 and the like, and a vertical extension plate 43b extending downward from the plate surface of the fixing plate 43a orthogonal to the plate surface. A fall prevention plate 43c extending from the lower end of the vertical extension plate 43b in a direction orthogonal to the plate surface of the vertical extension plate 43b is provided.
The fixing plate 43a is formed with a through hole 43d through which the anchor bolt 40 is passed, and the vertical extension plate 43b is formed with a long hole 43e formed so as to extend in the extension direction of the vertical extension plate 43b, and the fall prevention plate 43c is formed. A through screw hole 44f (see FIG. 6) into which a screw 47 for vertical adjustment is screwed is formed in.

The support side mounting member 44 extends from one end of the connecting plate 44a connected to the support 28 by a bracket and a connecting tool such as a bolt or a nut (not shown) in a direction orthogonal to the plate surface of the connecting plate 44a. A vertical movement connecting plate 44b that is connected to the vertical extension plate 43b in a state where the plate surface and the plate surface of the vertical extension plate 43b are in contact with each other is provided. The vertically moving connecting plate 44b is formed with a through hole 44c (see FIG. 6) through which the connecting bolt 45 penetrates.

The first mounting member 41 is mounted on the floor side and the plate surface of the vertically moving connecting plate 44b so that the upper end of the vertically moving connecting plate 44b of the support side mounting member 44 is located on the fixing plate 43a side of the floor side mounting member 43. The plate surface of the vertical extension plate 43b of the member 43 was brought into contact with the plate surface, and the plate surface forming the lower surface of the connecting plate 44a of the support side mounting member 44 and the plate surface forming the upper surface of the fall prevention plate 43c were opposed to each other. In this state, the connecting bolt 45 is passed through the through hole 44c of the vertically moving connecting plate 44b and the elongated hole 43e of the vertical extension plate 43b, and the nut 46 is fastened to the tip side of the connecting bolt 45 protruding from the elongated hole 43e. The support side mounting member 44 and the floor side mounting member 43 are connected.
Then, the screw 47 for vertical adjustment is passed through, for example, the screw hole of the double nuts 48 and 49 and the through screw hole 44f of the fall prevention plate 43c, and the tip 47t (see FIG. 6) of the screw 47 is connected to the connecting plate 44a. The first mounting member 41 is configured by contacting the plate surface forming the lower surface of the screw.

Therefore, since the fixing plate 43a of the first mounting member 41 is fixed to the lower surface 3u of the floor slab 3 with anchor bolts 40 or the like, the supports 28, 28 are fixed to the floor slab 3, and the cutting side array pulley group 21 Each of the plurality of driven pulleys 25, 25 ... Constituting the above is supported by the floor slab 3.
Then, with the first mounting member 41 fixed to the floor slab 3, the nut 46 fastened to the tip side of the connecting bolt 45 is loosened, and the screw 47 for vertical adjustment is moved up and down to move the connecting plate vertically. The vertical position of the support 28 connected to the 44a and the driven pulley 25 fixed to the support 28 via the bracket 25Z can be adjusted.

For example, by adjusting the vertical position adjusting mechanism of the three first mounting members 41 on the left side of FIG. 1 and adjusting the level of the support 28 on the left side of FIG. 1, the bracket 25Z is placed on the support 28. The two driven pulleys 25, 25 on the left side of FIG. 1 fixed in place can be positioned on the cut surface.
Further, by adjusting the vertical position adjusting mechanism of the three first mounting members 41 on the right side of FIG. 1 and adjusting the level of the support 28 on the right side of FIG. 1, the bracket 25Z is placed on the support 28. The two driven pulleys 25, 25 on the right side of FIG. 1 fixed in place can be positioned on the cut surface.

When the vertical position adjustment is completed, the vertical position of the driven pulley 25 is fixed by fastening the nut 46 on the tip side of the connecting bolt 45 and the double nuts 48 and 49.
That is, the first mounting member 41 has a long hole 43e, a connecting bolt 45, a nut 46, a screw 47 for vertical adjustment, etc., which enables the driven pulley 25 to move up and down the connecting plate 44a connected via the bracket 25Z. It is provided with a vertical position adjusting mechanism capable of adjusting the vertical position of the driven pulley 25.

The support frame 289 and the second mounting member 42 for mounting the support 30 to the lower surface 3u of the floor slab 3 are anchored to the lower surface 3u of the floor slab 3 as shown in FIGS. 5B and 3, for example. A floor-side mounting member 50 to be mounted by bolts 40 or the like, a bolt 51, and a support-side mounting member 52 connected to the bolt 51 so as to be movable in the extension direction of the bolt 51 are provided.
The floor side mounting member 50 is formed with a through hole 50a through which the anchor bolt 40 is penetrated, and the support side mounting member 52 is formed with a through hole 52a through which the bolt 51 is penetrated.

For example, as shown in FIG. 5B, the upper end (one end) of the bolt 51 is connected to the floor side mounting member 50 by a connector such as a bag nut 56 welded to the lower surface of the floor side mounting member 50, and the bolt The second mounting member 42 is configured by passing the lower end (other end) of the nut 51 through the screw hole of the nut 53, the through hole 50a of the floor side mounting member 50, the screw hole of the nut 54, and the screw hole of the nut 55. To.
Then, the upper end (one end) of the support body 29 of the support frame 289 is connected to the lower surface of the floor side mounting member 50 by a bracket and a connecting tool such as a bolt or a nut (not shown).
Further, the support 30 is movably attached to the support 29 via the slider 31 in the vertical direction, and the slider 31 and the support side mounting member 52 are connected via a connector such as a bracket 57. ..
Further, as shown in FIG. 3, the path conversion pulley 22 is connected to the support 30 via the bracket 22Z.

Therefore, the floor side mounting member 50 of the second mounting member 42 is fixed to the lower surface 3u of the floor slab 3 with anchor bolts 40 or the like, so that the support frame 289 and the support 30 are fixed to the floor slab 3 and the drive side. Each of the driven pulleys 27, 27 ... that constitutes the array pulley group 23 ..., the two path conversion pulleys 22, 22, the drive pulley 20, and the drive device of the wire saw 10 are supported by the floor slab 3.
Then, with the second mounting member 42 fixed to the floor slab 3, the path conversion pulley 22 connects the support side mounting member 52 via the bracket 22Z, the support 30, the slider 31, and the bracket 57. By moving it up and down, the vertical position of the path conversion pulley 22 can be adjusted.
That is, the second mounting member 42 has a bolt 51 and nuts 53, 54, 55 that enable the support side mounting member 52 to which the path conversion pulley 22 is connected to move up and down, and the path conversion pulley 22. It is equipped with a vertical position adjustment mechanism that allows the vertical position to be adjusted.

Therefore, by operating the vertical position adjusting mechanism of the first mounting member 41 and the vertical position adjusting mechanism of the second mounting member 42, the vertical positions of the driven pulleys 25 and 22 as the guiding means are adjusted, and these driven pulleys are adjusted. The wire saw 10 hung on the 25 and 22 can be positioned on the cut surface, and the planned cutting target portion 3A can be cut accurately.

According to the cutting method of the first embodiment, in a state where the cutting device 1 is fixed to the lower surface 3u of the floor slab 3, the pulley rotation motor and the pulley moving motor are driven, and the drive pulley 20 is rotated to obtain a plurality of parts. The wire saw 10 is circulated and moved between the driven pulley and the drive pulley 20 of the above, and the drive pulley 20 is moved in the vertical direction to pull the wire saw 10, so that the wire saw 10 is the cut target portion 3A. As it bites into the concrete, the concrete is cut.
At this time, the vertical position adjusting mechanism of the first mounting member 41 and the second mounting member 42 as the mounting means can adjust the vertical positions of the driven pulleys 25 and 22 according to the cutting target portion 3A, and the planned cutting can be performed. The target site 3A can be cut accurately.

As the cutting operation by the wire saw 10 progresses, the lower portion of the wire saw 10 in FIG. 1 moves to the upper side in FIG. Then, when the lower portion of the wire saw 10 reaches the positions of both the driven pulleys 25 and 25 on the lower side of FIG. 1, the drive of the wire saw 10 is stopped and the lower side of the wire saw 10 of FIG. 1 is stopped. Is removed from both lower driven pulleys 25 and 25, and after moving both lower driven pulleys 25 and 25 downward in FIG. 1, the drive of the wire saw 10 is restarted. After that, when the wire saw 10 reaches the driven pulley 25 on the upper left side of FIG. 1, the drive of the wire saw 10 is stopped, and the upper left part of FIG. 1 of the wire saw 10 is removed from the driven pulley 25 on the upper left. After moving the driven pulley 25 on the upper left to the upper side of FIG. 1, by restarting the driving of the wire saw 10, the floor slab 3 between the lower through hole 3a and the upper through hole 3a of FIG. 1 The site to be cut 3A can be cut.
Then, after separating the floor slab 3 in a predetermined range from the girder 2, the separated floor slab 3 is divided into an appropriate size that can be loaded by a crane and removed by a crane.

As described above, according to the cutting method of the first embodiment, the concrete to be the cut target portion 3A of the floor slab 3 in the vicinity of the boundary between the floor slab 3 attached to the upper surface 2t of the girder 2 and the upper surface 2t of the girder 2. When the portion is cut using the cutting device 1 having the wire saw 10, the wire saw 10 is driven with the drive mechanism and the guide means of the wire saw 10 attached to the lower surface 3u of the floor slab 3. The cutting target portion 3A of the floor slab 3 was cut.
That is, according to the cutting method of the first embodiment, by driving the wire saw 10 with the cutting device 1 attached only to the lower surface 3u of the floor slab 3, the vicinity of the boundary between the floor slab 3 and the upper surface 2t of the girder 2 Since the cutting target portion 3A of the floor slab 3 in the above is cut, in the floor slab renewal work, the cutting device 1 is installed on the lower surface 3u side of the floor slab 3 to cut the floor slab 3. It becomes possible to reduce the possibility of damaging the girder 2 which is a part to be reused other than the part to be cut and removed without impairing the use of the surrounding area, that is, the use of the road.

Further, according to the cutting device 1 of the first embodiment, since the guide means is composed of a plurality of pulleys (driven pulley group and drive pulley) on which the wire saw 10 is hung, the wire saw is located at a planned cutting position. You will be able to guide 10 with high accuracy.

Further, according to the cutting device 1 of the first embodiment, the wire saw 10, the drive mechanism of the wire saw 10, the drive pulley 20 and the driven pulley group as the guide means for guiding the wire saw 10, the guide means and the drive mechanism. Since the first mounting member 41 and the second mounting member 42 are provided as mounting means for mounting the plate on the lower surface 3u of the floor slab 3, the floor slab is installed on the lower surface 3u side of the floor slab 3 in the floor slab renewal work. 3 can be cut, and the use around the floor slab 3, that is, the possibility of damaging the girder 2 which is a reused part other than the part to be cut and removed without impairing the use of the road. A cutting device that can be lowered can be provided.

Further, according to the cutting device 1 of the first embodiment, the driven pulleys 25 and 22 are provided as guide means for guiding the wire saw 10, and the first mounting member 41 and the second mounting member 42 as mounting means are the driven pulley 25. , 22 is provided with a vertical position adjusting mechanism for adjusting the vertical position, so that the driven pulley 25 is in a state where the cutting device 1 is fixed to the lower surface 3u of the floor slab 3 by the first mounting member 41 and the second mounting member 42. Since the vertical position of the above and the vertical position of the path conversion pulley 22 can be aligned, the level of the cutting position (vertical height position) by the wire saw 10 can be freely set.
For example, in the splicing plate installation section where the splicing plate connecting the girder 2 and the girder 2 is installed, the driven pulley 25 is moved upward so as to escape obstacles such as bolts fixing the splicing plate and the splicing plate. The position can be set, and the possibility of damaging the girder 2 is reduced.

Further, according to the cutting device 1 of the first embodiment, the upper end of the rotation center shaft 25a of the driven pulley 25 is configured so as not to protrude upward from the upper surface 25r of the pulley 25, and the upper end of the rotation center shaft 25a is formed on the upper end. Since the low head screw 25d that functions as a bearing retainer is provided, the amount of protrusion of the pulley 25 (pulley body 25b) upward from the upper surface 25r is smaller than that of the pulleys 27 and 22 having a normal configuration.
Therefore, for example, when the driven pulley 25 is positioned below the inclined lower surface 3ut of the haunch (tapered) portion of the floor slab 3, the above-mentioned obstacles such as the splicing plate and bolts are placed in the above-mentioned splicing plate installation section. When it is desired to install the driven pulley 25 above so as to escape, the driven pulley 25 can be brought closer to the inclined lower surface 3ut and the lower surface 3u of the floor slab 3, and the above-mentioned obstacles such as the splicing plate and bolts can be used. It becomes possible to cut the upper position, and the possibility of damaging the girder 2 is reduced.
That is, the driven pulley 25 can be brought closer to the inclined lower surface 3ut and the lower surface 3u of the floor slab 3, and the effect of increasing the degree of freedom of the setting range when determining the cutting target portion can be obtained.

If the pulley cannot be installed above so as to escape obstacles such as splicing plates and bolts, it is necessary to stop the cutting operation with the wire saw so as not to cut the obstructions such as splicing plates and bolts. There is a problem, and work efficiency deteriorates.
On the other hand, according to the cutting device 1 according to the first embodiment, the driven pulley 25 is provided by using the vertical position adjusting mechanism capable of adjusting the vertical positions of the driven pulleys 25 and 22 and the driven pulley 25 provided with the low head screw 25d. Since the floor slab 3 is provided with a configuration that allows it to be closer to the inclined lower surface 3ut and the lower surface 3u, the driven pulley 25 can be installed so as to escape obstacles such as the splicing plate and bolts described above. The cutting operation can be efficiently performed without stopping the cutting operation by the wire saw 10.

Embodiment 2
The cutting device 1 of the first embodiment is configured to guide the wire saw 10 to the driven pulley 27 or the drive pulley 20 located directly below the path conversion pulley 22 via the path conversion pulley 22. FIG. As shown, a drive-side array pulley group 23A configured to guide the wire saw 10 to a driven pulley 27 or a drive pulley 20 located obliquely downward of the path conversion pulley 22 via a path conversion pulley 22 is provided. It may be a cutting device having a different configuration. The diagonally downward direction may be in any direction. That is, the diagonally downward direction can be set to any direction.

According to the cutting device according to the second embodiment, the length of the wire saw 10 can be increased, so that the range to be cut by the wire saw 10 can be increased.

Embodiment 3
In the first embodiment, the cutting side array pulley group 21 that guides the wire saw 10 in the cutting direction, at least two path conversion pulleys 22 and 22, and the drive side array pulley group 23 that guides the wire saw 10 to the drive side. Although the cutting device 1 provided with the guide means having the structure including the drive pulley 20 is illustrated, as shown in FIG. 8, the guide means are arranged in the cutting direction at a position facing the lower surface 3u of the floor slab 3. The cutting device 1 may be composed of a plurality of driven pulleys 25, 25 ... Arranged in the above and a drive pulley 20.
That is, the wire saw 10 is hung on the drive pulley 20 arranged in the cutting direction and the plurality of driven pulleys 25, 25 ..., And the drive pulley 20 moves in the cutting direction while rotating to pull the wire saw 10. As a result, the wire saw 10 may be a cutting device 1 configured to cut the cutting target portion 3A of the floor slab 3.

According to the third embodiment, it is possible to provide a cutting device 1 that can be effectively used in a field where a work space cannot be secured below the floor slab 3.

Embodiment 4
As shown in FIG. 9, instead of the cutting-side array pulley group 21 constituting the guide means described in the first embodiment, the wire saw 10 is cut in the cutting direction by being composed of the roller conveyors 5A and 5A and the driven pulleys 25 and 25. It may be a cutting device provided with a guide means for guiding the user.
The roller conveyors 5A and 5A are provided so as to extend along both edges of the upper surface 2t of the girder 2 in the width direction, that is, along the cutting direction.
The roller conveyor 5A is configured to include a plurality of rollers 5a, 5a ... Arranged so as to be arranged at a predetermined interval and rotatably provided with the rotation center axis 5b as the rotation center.
Further, the rotation center axes 5b, 5b ... Of the rollers 5a, 5a ... Are arranged on the same plane so as to be orthogonal to the extension direction of the upper surface 2t of the girder 2, for example.
The plurality of rollers 5a, 5a ... Constituting the roller conveyor 5A are configured such that, for example, both ends of the rotation center shaft 5b are rotatably supported by side plates 5c; 5c installed on both ends of the roller 5a.
Further, the roller conveyor 5A is provided, for example, with side plates 5c; 5c fixed on the supports 28, 28A arranged in parallel, which are connected to the first mounting members 41, 41.

According to the cutting apparatus according to the fourth embodiment, the roller conveyor 5A can accurately guide the wire saw 10 to a planned cutting position, which improves the cutting accuracy and cuts when the wire saw 10 is driven. The lower surface of the operating wire saw 10 and the rotatable circumferential surfaces of the rollers 5a, 5a ... Of the roller conveyor 5A come into contact with each other, and as the cutting progresses by the wire saw 10, the wire saw 10 causes the rollers 5a, 5a ... Since it moves smoothly on the cut surface formed on the rotatable circumferential surface of the wire saw 10, the cutting operation by the wire saw 10 becomes smooth.
The wire saw 10 during the disconnection operation is guided to the path conversion pulleys 22 and 22 by the driven pulleys 25 and 25.

Embodiment 5
As shown in FIG. 10, instead of the cutting side array pulley group 21 constituting the guide means described in the first embodiment, the wire saw 10 is cut in the cutting direction by being composed of the guide rollers 5B and 5B and the driven pulleys 25 and 25. It may be a cutting device provided with a guide means for guiding the user.
The guide rollers 5B and 5B are provided so as to extend along both edges of the upper surface 2t of the girder 2 in the width direction, that is, along the cutting direction.
The rotation center axes 5g, 5g ... Of the guide rollers 5B, 5B ... Are arranged on the same plane so as to extend along the extension direction of the upper surface 2t of the girder 2, for example.
The guide roller 5B has a configuration in which, for example, both ends of the rotation center shaft 5g are rotatably supported by end plates 5f; 5f installed on both ends of the guide roller 5B.
Further, the guide roller 5B is provided, for example, with the end plates 5f; 5f fixed on the support 28A arranged in parallel connected to the first mounting members 41, 41 ...

According to the cutting device according to the fifth embodiment, the guide roller 5B can guide the wire saw 10 to a planned cutting position with high accuracy, improving the cutting accuracy and cutting when the wire saw 10 is driven. The lower surface of the operating wire saw 10 and the rotatable circumferential surface of the guide roller 5B come into contact with each other, and as the cutting progresses by the wire saw 10, the wire saw 10 moves on the rotatable circumferential surface of the guide roller 5B. Since it moves smoothly on the formed cut surface, the cutting operation by the wire saw 10 becomes smooth.
The wire saw 10 during the disconnection operation is guided to the path conversion pulleys 22 and 22 by the driven pulleys 25 and 25.

That is, according to the cutting device according to the fourth embodiment and the fifth aspect, the guide means is a roller (roller 5a, guide roller 5B) having a rotatable circumferential surface that comes into contact with the lower surface of the wire saw 10 during the cutting operation. ) Is provided, the roller can guide the wire saw 10 to the planned cutting position with high accuracy, and the cutting accuracy is improved. At the same time, the wire saw 10 moves smoothly on the roller, and the wire saw 10 is provided. The cutting operation according to 10 can be performed smoothly.
Further, according to the cutting device according to the fourth embodiment and the fifth aspect, the work of removing the wire saw 10 from the driven pulley 25 in the middle of the cutting operation can be reduced as compared with the case where the cutting side array pulley group 21 is used. , The work of the worker can be simplified.

The guide means has a rotatable spherical surface that contacts the lower surface of the wire saw 10 during the cutting operation instead of a roller having a rotatable circumferential surface that contacts the lower surface of the wire saw 10 during the cutting operation. It may be configured to include a plurality of spheres.

Further, the guide means may be configured to include a belt conveyor instead of a roller having a rotatable circumferential surface that contacts the lower surface of the wire saw 10 during the cutting operation.

Embodiment 6
In the cutting apparatus according to the fourth embodiment and the fifth aspect, as shown in FIGS. 9 and 10, the rotatable girder 2 comes into contact with the lower surface of the wire saw 10 during the cutting operation along both edges in the width direction. An example of a configuration in which roller conveyors 5A and 5A and guide rollers 5B and 5B having a smooth circumferential surface are arranged is illustrated, but the lower surface of the wire saw 10 being cut along one end edge in the width direction of the girder 2 Using a cutting device having a configuration in which a roller having a rotatable circumferential surface in contact is arranged and a pulley for guiding the wire saw 10 during the cutting operation is arranged along the other end edge in the width direction of the girder 2. , The cutting target portion 3A of the floor slab 3 may be cut.
According to the sixth embodiment, the wire saw 10 can be accurately guided to the planned cutting position by the roller and the pulley, the cutting accuracy is improved, and the wire saw 10 moves smoothly on the roller to move the wire saw 10 smoothly. The cutting operation according to 10 can be performed smoothly.

In the cutting device of each embodiment, the mounting means includes a configuration in which the vertical position adjusting mechanism for adjusting the vertical position of the guide means is provided. However, the guide means is not provided with the vertical adjusting mechanism. The pulley, the roller conveyor 5A, and the guide roller 5B may be provided with a vertical position adjusting mechanism that can individually adjust the vertical position.

Further, in each embodiment, the configuration in which the cutting device 1 is attached to the lower surface 3u is illustrated, but the cutting device 1 may be attached to the inclined lower surface 3ut of the haunch portion of the floor slab 3. For example, the first mounting member 41 may be mounted on the inclined lower surface 3ut of the haunch portion of the floor slab 3.

Further, in each embodiment, an example is shown in which guide means such as a pulley, a roller conveyor 5A, and a guide roller 5B are provided at positions along both end edges of the girder 2 in the width direction. The means may be provided only at a position along one of the two edges of the girder 2 in the width direction.

Further, in each embodiment, a method of cutting a floor slab as a concrete structure as a cutting target has been exemplified, but the cutting target may be a structure such as a concrete structure or a steel structure other than the floor slab. ..
For example, since the present invention can also be applied to cutting structures such as road bridges, railway bridges, box culverts, and wall balustrades, a cutting device is installed on the lower surface side of such structures to form the structure. It becomes possible to cut an object without impairing the utilization around the structure, and to reduce the possibility of damaging the reused part other than the part to be cut and removed.
That is, in a method of cutting a structure by using a wire saw, a wire saw drive mechanism, and a cutting device having a wire saw guide portion, the wire saw drive mechanism and a guide are used. The structure may be cut by driving the wire saw with the portion attached to the lower surface of the structure.

1 Cutting device, 2 digits, 3 floor slab (concrete structure),
3u Underside of floor slab (concrete structure), 5A roller conveyor (roller),
5B guide roller (roller), 10 wire saw, 20 drive pulley,
22, 25, 27 driven pulley, 25a pulley rotation center axis,
Top surface of 25r pulley, 41 1st mounting member (mounting means),
42 Second mounting member (mounting means).

Claims (10)

In a method of cutting a structure by cutting a structure with a wire saw using a cutting device having a wire saw, a drive mechanism of the wire saw, and a guide means for guiding the wire saw.
A method for cutting a structure, which comprises cutting the structure by driving the wire saw with the drive mechanism and the guide means of the wire saw attached to the lower surface of the structure. The structure according to claim 1, wherein the structure is a floor slab attached to the upper surface of the girder, and the cut target portion of the floor slab is cut in the vicinity of the boundary between the floor slab and the upper surface of the girder. How to cut. The method for cutting a structure according to claim 2, wherein the cutting target portion is above the splicing plate that connects the girders and the bolt that fixes the splicing plate. A roller having a rotatable circumferential surface that contacts the lower surface of the wire saw during the cutting operation is arranged along one end edge in the width direction of the girder, and the cutting operation is performed along the other end edge in the width direction of the girder. The method for cutting a structure according to claim 2 or 3, wherein a pulley for guiding the wire saw is arranged. A cutting device used in the method for cutting a structure according to any one of claims 1 to 4.
A cutting device including a wire saw, a drive mechanism for the wire saw, a guide means for guiding the wire saw, and a mounting means for mounting the guide means and the drive mechanism on the lower surface of a structure. The cutting device according to claim 5, further comprising a vertical position adjusting mechanism for adjusting the vertical position of the guide means. The cutting device according to claim 5, wherein the mounting means includes a vertical position adjusting mechanism for adjusting the vertical position of the guide means. The cutting device according to any one of claims 5 to 7, wherein the guide means includes a plurality of pulleys over which a wire saw is hung. The cutting device according to claim 8, wherein the rotation center axis of each pulley is configured so as not to protrude upward from the upper surface of the pulley. The cutting device according to any one of claims 5 to 7, wherein the guide means includes a roller having a rotatable circumferential surface that contacts the lower surface of the wire saw during the cutting operation. ..

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