Cut-remove method of concrete slab

Abstract

To provide a cut-remove method of a slab using a wire saw device to reduce risk of cut concrete slab fall by cutting the concrete slab obliquely to a horizontal surface along a steel girder.SOLUTION: A cut-remove method of a concrete slab cutting and removing a connection part C3 of a steel girder H1 of concrete slabs C1, C2 cuts obliquely to a horizontal surface of the connection part C3 of the steel girder H1 of the concrete slabs C1, C2 along the steel girder H1 using a wire saw device 1 so as to cut a deviation stopper (a stud dowel with a head S1) attached on an upper flange of the girder H1.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for cutting and removing a deck, and more particularly to a method for cutting and removing a concrete deck, which is a composite deck, using a wire saw device. [Background technology]

[0002] Conventionally, concrete structures have been cut and removed using a wire saw device. For example, Patent Document 1 filed by the applicants of the present application describes cutting a deck girder using a wire cutting machine that includes a first rail and a second rail that face each other in a first direction with an object to be cut between them and extend in a second direction intersecting the first direction, a first moving device that is attached to the first rail and includes a first pulley, a second moving device that is attached to the second rail and includes a second pulley, a wire that is hung on the first pulley and the second pulley, and a mechanism that is provided on at least one of the first pulley and the second pulley and supplies power, the first moving device moving along the first rail, and the second moving device automatically moving along the second rail to cut the object to be cut (see claim 1 of Patent Document 1, paragraphs

[0028] to

[0047] of the specification, and Figures 1 to 5 of the drawings, etc.).

[0003] In recent years, as shown in Fig. 10, the time for updating composite decks has come, and attempts have been made to cut and remove the joint C3 between the concrete decks C1 and C2, which are difficult to dismantle and remove, and the headed stud dowel S1 protruding from the upper flange of the steel girder H1, using a wire saw device. However, the conventional method of cutting and removing such composite decks involves cutting the concrete decks C1 and C2 along the vertical cutting line B1 with a concrete cutter, dismantling and removing the concrete decks C1 and C2 using a jack-up or similar tool, and then cutting and removing the remaining joint C3 along the horizontal cutting line B2 shown by the dashed line using a wire saw device, and chipping and removing the remaining concrete with an air pick or similar tool. This has led to the problem that dismantling and removing the composite decks requires time and effort, resulting in high costs.

[0004] Furthermore, for example, Patent Document 2 discloses a bridge structure that includes one guide device arranged on one inclined surface side and another guide device arranged on the other inclined surface side, each of which has a guide shaft with a wire saw on its upper surface and a plurality of shaft support sections across which the guide shaft is supported, and which uses a wire saw that is arranged symmetrically across a bridge girder to horizontally cut and remove the joint between the steel girder and the concrete deck of a composite girder (see claim 1 in Patent Document 2, paragraphs

[0016] to

[0033] of the specification, and Figures 1 to 6 of the drawings, etc.).

[0005] In addition, Patent Document 3 discloses a cutting device for cutting and separating a joint between a concrete deck and a main girder of a bridge, the cutting device including a wire saw that forms a cut surface along the main girder at the joint, a driven pulley that guides the wire saw in a direction along the cut surface, a support mechanism that is detachably installed on the main girder, and a drive unit that is supported by the support mechanism and causes the wire saw to travel in a circular motion, and the cutting device horizontally cuts and removes the joint between a steel girder of a composite girder and a concrete deck (see claim 1 in the claims of Patent Document 3, paragraphs

[0058] to

[0069] of the specification, and Figures 1, 6, and 8 of the drawings, etc.).

[0006] However, the method of horizontally cutting and removing the joint between the steel girder and the concrete deck of a composite girder using a guide device and wire saw described in Patent Document 2, and the method of horizontally cutting and removing the joint between the steel girder and the concrete deck of a composite girder using a cutting device described in Patent Document 3, require a large-scale guide device, as described in Patent Document 2, to avoid damaging the steel girder, and because the thickness of the upper flange of the steel girder changes and there is a splice plate, it is necessary to cut at a height significantly away from the upper flange of the steel girder. For this reason, there is a problem that these methods cannot be applied when the haunch of the concrete deck is small.

[0007] On the other hand, a method of removing the joint between the concrete deck and the steel girder by cutting it diagonally is also known. For example, Patent Document 4 discloses a removal method including the steps of cutting a girder portion of a composite deck that is located on a steel girder and includes a shear stopper from one or both sides in the bridge width direction with a blade to form a cutting groove so as to cut the shear stopper, and removing an upper portion of the girder portion that is located above the cutting groove, in which the blade is inclined with respect to the upper surface of the steel girder so that the part of the blade that protrudes into the girder portion is located above the opposite part in the bridge width direction when viewed from the bridge axis direction in the step of forming the cutting groove (see claim 1 of Patent Document 4, paragraphs

[0028] to

[0039] of the specification, and Figures 1 to 7 of the drawings, etc.).

[0008] However, the removal method described in Patent Document 4 requires that the concrete deck be cut and removed while leaving the joints with the steel girders, and that temporary support mechanisms such as vents be constructed to prevent the concrete deck from falling. This means that the removal and renewal work of the concrete deck is labor-intensive, and there is a risk of the deck falling, posing safety issues.

[0009] Patent Document 5 discloses a method for removing a concrete slab, which includes the steps of: inserting a blade of a cutting device from above the concrete slab at a predetermined angle from the planar direction of the slab toward the upper direction of the slab to separate and cut the connecting members in the vertical direction, thereby intermittently forming cutting lines on the concrete slab that separate the heads of the cut connecting members from the main girders without partially removing the concrete slab; and removing the concrete slab from the main girders with the heads of the cut connecting members still embedded, while leaving the bases of the cut connecting members in the main girders (see claim 1 in the claims of Patent Document 5, paragraphs

[0026] to

[0034] of the specification, and Figures 1 to 6 of the drawings, etc.).

[0010] However, in the concrete deck removal method described in Patent Document 5, instead of cutting diagonally along the steel girder, cutting diagonally along the direction perpendicular to the bridge axis with a cutting device such as a concrete cutter, it is necessary to cut with the cutting device multiple times or with multiple cutting devices, which results in a problem of time-consuming work and high labor costs. Moreover, in the concrete deck removal method described in Patent Document 5, the studs fused to the upper flange of the steel girder are cut with a concrete cutter while still embedded in the concrete, so there is also a problem that even if the position of the stud is measured accurately, the risk of damaging the steel girder cannot be eliminated. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] JP 2022-187246 A [Patent Document 2] Patent Publication No. 2023-65755 [Patent Document 3] JP 2023-91593 A [Patent Document 4] JP 2023-1686 A [Patent Document 5] Patent No. 6895201 Summary of the Invention [Problem to be solved by the invention]

[0012] Therefore, the present invention has been devised in consideration of the above-mentioned problems, and its object is to provide a method of cutting and removing a concrete slab using a wire saw which reduces the risk of the cut concrete slab falling by cutting the concrete slab along a steel girder at an angle to the horizontal plane. [Means for solving the problem]

[0013] The method for cutting and removing a concrete deck according to claim 1 is a method for cutting and removing a concrete deck by cutting and removing the joint between the concrete deck and the steel girder, characterized in that a wire saw device is used to cut the joint between the concrete deck and the steel girder at an angle to the horizontal plane along the steel girder so as to cut the slip stopper attached to the upper flange of the steel girder.

[0014] The method for cutting and removing a concrete deck according to claim 2 is characterized in that, in the method for cutting and removing a concrete deck according to claim 1, the anti-friction material is a headed stud dowel, and when a wire saw device is used to cut the joint between the concrete deck and the steel girder along the steel girder at an angle to the horizontal plane, the heads of all of the headed stud dowels arranged in parallel to the steel girder in a direction perpendicular to the bridge axis are cut off.

[0015] The method for cutting and removing a concrete floor slab of claim 3 is characterized in that, in the method for cutting and removing a concrete floor slab of claim 1, a wire saw device is used to cut the joint portion of the concrete floor slab with the steel girder at a position along the steel girder to cut the slip stopper material, along a first cutting line that is inclined obliquely with respect to a horizontal plane, and a wire saw device is used to cut the joint portion of the concrete floor slab with the steel girder at a position along the steel girder to cut the slip stopper material, along a second cutting line that is inclined obliquely with respect to the horizontal plane and intersects with the first cutting line.

[0016] The method for cutting and removing a concrete deck according to claim 4 is the method for cutting and removing a concrete deck according to claim 3, characterized in that the anti-friction material is a headed stud dowel, and the heads of all of the headed stud dowels arranged in parallel with the steel girder in a direction perpendicular to the bridge axis are cut off at the first cutting line.

[0017] The method for cutting and removing a concrete floor slab of claim 5 is characterized in that, in the method for cutting and removing a concrete floor slab of claim 3, after cutting along the first cutting line, the cut concrete floor slab is cut along the second cutting line before being removed.

[0018] The method for cutting and removing a concrete floor slab according to claim 6 is a method for cutting and removing a concrete floor slab according to any of claims 1 to 5, characterized in that the wire saw has a pair of upper and lower rails installed along the steel girders on the upper and lower surfaces of the concrete floor slab, and cuts by moving a pulley along these rails while pressing in the cutting direction. Effect of the Invention

[0019] According to the inventions of claims 1 to 6, the joint between the concrete deck and the steel girder is cut diagonally, in the same way as cutting anti-slip materials such as headed stud bolts attached to the upper flange of the steel girder. Therefore, even if the thickness of the upper flange of the steel girder changes or if a splice plate is present, the joint can be cut without damaging the steel girder. Even if the haunch of the concrete deck is small, the concrete deck can be cut and removed without applying time-consuming removal methods such as conventional jacking up.

[0020] Furthermore, according to the inventions of claims 1 to 6, since the concrete slab is cut at an angle, the risk of the concrete slab falling can be reduced without the need to install fall prevention facilities such as vents below, as was the case in the conventional method of cutting the concrete slab vertically.

[0021] In particular, according to the inventions of claims 2 and 4, when the joint between the concrete deck and the steel girder is cut at an angle to the horizontal plane and when cutting along the first cutting line, all of the heads of the headed stud dowels arranged in parallel with the steel girder in a direction perpendicular to the bridge axis are cut off, so that the deck above the diagonally cut concrete deck can be easily removed.

[0022] In particular, according to the invention of claim 5, the concrete floor slab to be cut and removed along the first cutting line can be used as a support for the wire saw and the joint portion can be cut along the second cutting line, eliminating the need to assemble and remove unnecessary temporary members and reducing the labor costs of cutting and removing the concrete floor slab.

[0023] In particular, according to the invention of claim 6, since the pulley moves along the rail and is pressed in the cutting direction while being pushed to cut, there is no need to provide a pulley that is not related to the part currently being cut, making it possible to miniaturize and simplify the overall configuration of the machine and reduce the installation cost of the wire saw. Also, according to the invention of claim 5, the part where the wire saw rotates is limited, reducing the risk of an operator being caught in the wire saw during cutting and improving safety. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 is a vertical cross-sectional view taken along a direction perpendicular to a bridge axis, showing the configuration of a wire saw according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a process explanatory diagram showing a first through hole drilling process of the concrete floor slab cutting and removal method according to the embodiment of the present invention. [Diagram 3] FIG. 3 is a process explanatory diagram showing the wire saw assembly and installation process of the above concrete floor slab cutting and removal method. [Figure 4] FIG. 4 is a process explanatory diagram showing a first cutting line cutting process of the above concrete floor slab cutting and removal method. [Diagram 5] FIG. 5 is a process explanatory diagram showing a second through hole drilling process of the above concrete floor slab cutting and removal method. [Figure 6] FIG. 6 is a process explanatory diagram showing the wire saw assembly and installation process of the above concrete floor slab cutting and removal method. [Figure 7] FIG. 7 is a process explanatory diagram showing the second cutting line cutting process of the concrete floor slab cutting and removal method. [Figure 8]FIG. 8 is a process explanatory diagram showing the slab removal process of the concrete slab cutting and removal method. [Figure 9] FIG. 9 is a process explanatory diagram showing the remaining concrete portion chipping process in the concrete floor slab cutting and removal method. [Figure 10] FIG. 10 is a diagram showing an outline of a conventional method for cutting and removing a composite deck. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Hereinafter, a method for cutting and removing a concrete floor slab according to the present invention will be described in detail with reference to the drawings.

[0026] <Wire saw device> First, a wire saw device 1 according to an embodiment of the present invention (hereinafter, simply referred to as the wire saw device 1) used in a method for cutting and removing a concrete floor slab according to an embodiment of the present invention will be described with reference to Fig. 1. Fig. 1 is a vertical cross-sectional view taken along a direction perpendicular to the bridge axis, showing the configuration of the wire saw device 1.

[0027] The wire saw device 1 according to this embodiment is installed above and below concrete slabs C1 and C2, which are composite slabs firmly joined with headed stud dowels S1, which are shear stoppers protruding from the top surface of the upper flange of the steel girder H1 at the joint C3 at the top of the steel girder H1, and the joint C3 is cut. X in the figure indicates the bridge axis direction X along the steel girder H1, and Y in the figure indicates the bridge axis perpendicular direction Y, which is the horizontal direction perpendicular to the bridge axis direction X. Z in the figure indicates the up-down direction.

[0028] The wire saw device 1 of this embodiment is not a wire saw device that uses many pulleys to gradually shorten and reduce the wire saw's path as the cutting progresses, as in a normal wire saw device, to perform pull-cut cutting, but rather is a moving pulley-type wire saw device that uses a moving pulley that travels on a rail and moves, similar to the wire cutting machine described in Patent Document 1, to perform push-cut cutting while pressing in the cutting direction.

[0029] This wire saw device 1 comprises a pair of upper and lower rails, a first rail 11 and a second rail 12, which face each other across concrete floor slabs C1, C2, a first movable pulley 2 that moves while running on the first rail 11, and a second movable pulley 3 that moves while running on the second rail 12.

[0030] (1st rail 11) The first rail 11 is a rail fixed onto the concrete deck C2 with post-installed anchors or the like, and is installed along the bridge axis direction X, which is the cutting direction. In addition, a rack gear (not shown) is formed on this first rail 11, which meshes with a pinion gear of a moving motor of the first moving pulley 2 (described later), and this rack gear has the function of guiding the first moving pulley 2 in the cutting direction.

[0031] Furthermore, as shown in FIG. 1, the upper surface of the first rail 11 is an inclined surface 11a that is inclined by α° with respect to the horizontal plane, and the angle of this inclined surface 11a also serves to determine the first cutting line A1 and perform oblique cutting.

[0032] (First moving pulley) The first moving pulley 2 includes a moving device 20 that runs on the first rail 11 , a drive motor 21 , a drive pulley 22 that is driven by the drive motor 21 , and a cover 23 that covers the drive pulley 22 .

[0033] This moving device 20 has a moving motor (not shown), which is an electric motor, and a pulley, and is a device in which the pinion gear of the moving motor of the first moving pulley 2 meshes with the rack gear of the first rail 11, causing the first moving pulley 2 to move along the rack gear along the first rail 11 using the rotational driving force of the moving motor.

[0034] (Second rail) Similarly, as shown in Fig. 1, the second rail 12 is a rail fixed to the underside of the concrete floor slab C1 with post-installed anchors or the like so as to face the first rail 11 at a position symmetrical in rotation with the concrete floor slabs C1 and C2 in between, and is installed along the cutting direction, that is, the bridge axis direction X. Also, the second rail 12 is formed with a rack gear (not shown) that meshes with the pinion gear of the movement motor of the second moving pulley 3 (described later), and this rack gear has the function of guiding the second moving pulley 3 in the cutting direction.

[0035] Furthermore, as shown in FIG. 1, the upper surface of the second rail 12 has an inclined surface 12a that is inclined by α° with respect to the horizontal plane, and the angle of this inclined surface 12a determines the first cutting line A1, thereby performing oblique cutting.

[0036] (Second moving pulley) The second moving pulley 3 includes a moving device 30 that runs on the second rail 12 , a driven pulley 32 that is driven by the driving force of the drive motor 21 described above, and a cover 33 that covers the driven pulley 32 .

[0037] This moving device 30 has a moving motor (not shown), which is an electric motor, and a pulley, and is a device in which the pinion gear of the moving motor of the second moving pulley 3 meshes with the rack gear of the second rail 12, causing the second moving pulley 3 to move along the rack gear along the second rail 12 using the rotational driving force of the moving motor.

[0038] (Wire saw) A loop-shaped wire saw 4 is wound around the drive pulley 22 and driven pulley 32. The wire saw 4 is an endless rope with diamond chips embedded in it as an abrasive material, and has the function of scraping and cutting the concrete by coming into contact with it and sliding (sliding) against it.

[0039] <How to cut and remove concrete floor slabs> Next, a method for cutting and removing a concrete floor slab according to an embodiment of the present invention will be described with reference to Figs. 2 to 9.

[0040] (1st through hole drilling process) First, as shown in Fig. 2, the method for cutting and removing a concrete floor slab according to this embodiment includes a first through hole drilling step of drilling a first through hole h1 inclined by α° with respect to the horizontal plane corresponding to a first cutting line A1 (see Fig. 1) for inserting the wire saw 4 of the wire saw device 1 in the joint part C3. Fig. 2 is a process explanatory diagram showing the first through hole drilling step of the method for cutting and removing a concrete floor slab according to this embodiment.

[0041] In this process, a first through hole h1 of a predetermined diameter (e.g., 52 mm) through which a wire saw 4 can be inserted is drilled in the joint C3 between the concrete decks C1, C2 and the steel girder H1 using a drilling machine such as a core drill or grinding drill (not shown). However, since the wire saw 4 is loop-shaped, in this process, two first through holes h1, h1 arranged in parallel with each other and separated by the diameter of the driving pulley 22 and the driven pulley 32 are drilled. The inclination angle α with respect to the horizontal plane is appropriately set according to the height of the haunch part of the joint C3 and the thickness of the upper flange and splice plate of the steel girder H1.

[0042] (Wire saw assembly and installation process) Next, as shown in Fig. 3, the method for cutting and removing a concrete floor slab according to this embodiment includes a wire saw assembly and installation process for assembling and installing the above-mentioned wire saw device 1. Fig. 3 is a process explanatory diagram showing the wire saw assembly and installation process of the method for cutting and removing a concrete floor slab according to this embodiment.

[0043] Specifically, in this process, the first rail 11 and the second rail 12 are fixed to the upper and lower surfaces of the concrete floor slabs C1, C2 with post-installed anchors or the like. Then, the first movable pulley 2 is installed on the first rail 11, and the second movable pulley 3 is installed on the second rail 12. After that, the loop-shaped wire saw 4 is wound around the driving pulley 22 and driven pulley 32 and installed.

[0044] (First cutting line cutting process) Next, as shown in Fig. 4, in the method for cutting and removing a concrete floor slab according to this embodiment, a first cutting line cutting step is performed using a first cutting line A1. Fig. 4 is a process explanatory diagram showing the first cutting line cutting step of the method for cutting and removing a concrete floor slab according to this embodiment.

[0045] Specifically, in this process, the wire saw 4 wound around the drive pulley 22 and the driven pulley 32 is rotated by the drive pulley 22, and the first moving pulley 2 and the second moving pulley 3 run on the first rail 11 and the second rail 12, respectively, to push and move the wire saw 4 in the cutting direction, that is, the bridge axis direction X, from the first through hole h1, so that the wire saw 4 pushes through the joint portion C3 and cuts the concrete floor slabs C1 and C2 along the first cutting line A1 to separate them into the concrete floor slab C1 and the concrete floor slab C2.

[0046] At this time, the concrete floor slabs C1 and C2 are cut at an angle, so there is no risk of them falling as in the conventional case where the concrete floor slabs are cut in the vertical direction, and there is no need to install fall prevention facilities such as vents below.

[0047] In addition, because the cutting is done on the diagonal first cutting line A1 that passes through the headed stud dowel S1, which acts as a shear stopper, the concrete decks C1, C2 can be easily removed after cutting by simply lifting them with a crane, and even if the thickness of the upper flange of the steel girder H1 has changed or there is a splice plate, the joint part C3 can be cut without damaging the steel girder H1. Therefore, even if the haunches of the concrete decks C1, C2 are small, the concrete decks can be cut and removed without applying the time-consuming removal methods such as jacking up.

[0048] Furthermore, in this process, it is preferable to cut off the heads of both headed stud dowels S1, S1 that are arranged side by side on the upper flange of the steel girder H1 along the direction perpendicular to the bridge axis Y at the first cutting line A1. Of course, if there are three or more headed stud dowels S1 arranged side by side on the steel girder H1 in the direction perpendicular to the bridge axis Y, it is preferable to cut off the heads of all of the stud dowels S1. This is because this makes it easier to remove the concrete deck C1, which is the upper deck that was cut diagonally along the first cutting line.

[0049] (Second through hole drilling process) Next, as shown in Fig. 5, in the method for cutting and removing a concrete floor slab according to this embodiment, before removing the concrete floor slab C1, a second through hole drilling step is performed to drill a second through hole inclined at -α° with respect to the horizontal plane corresponding to the second cutting line A2 for inserting the wire saw 4 of the wire saw device 1 in the joint portion C3. Fig. 5 is a process explanatory diagram showing the second through hole drilling step of the method for cutting and removing a concrete floor slab according to this embodiment.

[0050] In this process, as in the first through hole drilling process, two second through holes h2, h2 arranged in parallel and separated by a diameter of the drive pulley 22 and the driven pulley 32, each having the same diameter as the first through hole h1 through which the wire saw 4 can be inserted, are drilled in the joint portion C3 using a drilling machine.

[0051] In addition, in this step, the first through hole h1 and the second through hole h2 may be drilled simultaneously in parallel with the above-mentioned first through hole drilling step.

[0052] (Wire saw assembly and installation process) Next, as shown in Fig. 6, the method for cutting and removing a concrete floor slab according to this embodiment includes a wire saw assembly and installation process for assembling and installing a wire saw device 1' that is symmetrical to the above-mentioned wire saw device 1. Fig. 6 is a process explanatory diagram showing the wire saw assembly and installation process of the method for cutting and removing a concrete floor slab according to this embodiment.

[0053] Specifically, in this process, the first rail 11' is fixed to the upper surface of the separated concrete floor slab C1 with post-installed anchors or the like, and the second rail 12' is fixed to the lower surface of the concrete floor slab C2 with post-installed anchors or the like. Then, the first movable pulley 2' is installed on the first rail 11', and the second movable pulley 3' is installed on the second rail 12'. After that, the loop-shaped wire saw 4 is wound around and installed on the drive pulley 22' and driven pulley 32'.

[0054] (Second cutting line cutting process) Next, in the method for cutting and removing a concrete floor slab according to this embodiment, a first cutting line cutting step is performed using a second cutting line A2, as shown in Fig. 7. Fig. 7 is a process explanatory diagram showing the second cutting line cutting step of the method for cutting and removing a concrete floor slab according to this embodiment.

[0055] Specifically, in this process, the wire saw 4 wound around the drive pulley 22' and driven pulley 32' is rotated by the drive pulley 22', and the first moving pulley 2' and the second moving pulley 3' run on the first rail 11' and the second rail 12' respectively, thereby pushing and moving the wire saw 4 in the cutting direction, that is, the bridge axis direction X, from the second through hole h2, so that the wire saw 4 pushes through the joint portion C3 and further cuts the concrete floor slab C1 along the second cutting line A2 to separate it into the concrete floor slab C1 and the joint portion C3.

[0056] (Floor slab removal process) Next, as shown in Fig. 8, in the method for cutting and removing a concrete slab according to this embodiment, a slab removal process is performed in which the cut concrete slabs C1 and C2 are lifted and removed by a lifting machine. Fig. 8 is a process explanatory diagram showing the slab removal process of the method for cutting and removing a concrete slab according to this embodiment.

[0057] (Remaining concrete chipping process) Next, as shown in Fig. 9, the method for cutting and removing a concrete floor slab according to this embodiment includes a remaining concrete portion chipping step in which the remaining concrete portion C3' shown shaded in Fig. 9 is chipped off and removed with a chipping machine such as an air pick. Fig. 9 is a process explanatory diagram showing the remaining concrete portion chipping step in the method for cutting and removing a concrete floor slab according to this embodiment.

[0058] Upon completion of this process, the concrete floor slab cutting and removal work using the concrete floor slab cutting and removal method according to this embodiment is completed.

[0059] According to the method for cutting and removing concrete floor slabs of this embodiment described above, the joint C3 between the concrete floor slabs C1, C2 and the steel girder H1 is cut diagonally, in the same way as cutting a slip-stop material such as a headed stud dowel S1 attached to the upper flange of the steel girder H1. Therefore, even if the thickness of the upper flange of the steel girder H1 changes or if a splice plate is present, the joint C3 can be cut without damaging the steel girder H1, and even if the haunches of the concrete floor slabs C1, C2 are small, the concrete floor slabs can be cut and removed without applying time-consuming removal methods such as conventional jacking up.

[0060] Furthermore, according to the method for cutting and removing concrete slabs according to this embodiment, the concrete slabs C1, C2 can be easily removed after cutting by simply lifting them with a crane, and even if the thickness of the upper flange of the steel girder H1 has changed or there is a splice plate, the joint portion C3 can be cut without damaging the steel girder H1. Therefore, even if the haunches of the concrete slabs C1, C2 are small, the concrete slabs can be cut and removed without applying the conventional removal method that requires time, such as jacking up.

[0061] Furthermore, according to the method for cutting and removing concrete floor slabs in this embodiment, the concrete floor slabs C1, C2 are cut diagonally, which reduces the risk of the concrete floor slabs C1, C2 falling without the need to install fall prevention facilities such as vents below, as is the case when cutting the concrete floor slabs C1, C2 in the vertical direction as in the conventional method.

[0062] In addition, according to the method for cutting and removing a concrete floor slab in this embodiment, the concrete floor slab C1 to be cut and removed along the first cutting line A1 can be used as a support for the wire saw device 1' to cut the joint portion C3 along the second cutting line A2, eliminating the need to assemble and remove unnecessary temporary members and reducing the labor costs of cutting and removing the concrete floor slab.

[0063] The concrete floor slab cutting and removal method and wire saw device 1, 1' according to the embodiment of the present invention have been described in detail above. However, the above-mentioned and illustrated embodiments are merely specific embodiments for carrying out the present invention. Therefore, the technical scope of the present invention should not be interpreted as being limited by these. [Explanation of symbols]

[0064] 1,1': Wire saw device 11,11': First rail 11a,11a': Inclined surface 12,12': 2nd rail 12a,12a': Inclined surface 2,2': First moving pulley 20,20':Moving device 21,21': Drive motor 22,22': Drive pulley 23: Cover 3,3': Second moving pulley 30,20': Moving device 32,32': Drive pulley 33: Cover 4: Wire saw h1: 1st through hole (through hole) h2: 2nd through hole (through hole) A1: First cutting line A2: Second cutting line B1: Vertical cutting line B2: Horizontal cutting line C1, C2: Concrete floor slab C3: Joint part C3': Remaining concrete area H1: Steel girder S1: Headed stud dowel (slip prevention)

Claims

1. A method for cutting and removing a concrete slab by cutting and removing a joint between a concrete slab and a steel girder, comprising: Using a wire saw device, cut the joint between the concrete deck and the steel girder along the steel girder at an angle to the horizontal plane so as to cut the anti-slip material attached to the upper flange of the steel girder. A method for cutting and removing a concrete floor slab, comprising:

2. The anti-friction material is a headed stud dowel, and when cutting the joint between the steel girder and the concrete deck slab along the steel girder at an angle to the horizontal plane using a wire saw device, all the heads of the headed stud dowels arranged in parallel with the steel girder in the direction perpendicular to the bridge axis are cut off.

2. A method for cutting and removing a concrete floor slab according to claim 1.

3. Using a wire saw device, at a position along the steel girder where the shear stopper is to be cut, a joint portion between the concrete floor slab and the steel girder is cut along a first cutting line that is inclined obliquely with respect to a horizontal plane, and using a wire saw device, at a position along the steel girder where the shear stopper is to be cut, a joint portion between the concrete floor slab and the steel girder is cut along a second cutting line that is inclined obliquely with respect to a horizontal plane and intersects with the first cutting line.

2. The method for cutting and removing a concrete floor slab according to claim 1 .

4. The anti-friction material is a headed stud dowel, and all heads of the headed stud dowels arranged in parallel on the steel girder in a direction perpendicular to the bridge axis are cut off at the first cutting line.

4. The method for cutting and removing a concrete floor slab according to claim 3,

5. After cutting along the first cutting line, cutting along the second cutting line before removing the cut concrete floor slab.

4. The method for cutting and removing a concrete floor slab according to claim 3,

6. The wire saw device is provided with a pair of upper and lower rails along the steel girders on the upper and lower surfaces of the concrete floor slab, and cuts the concrete floor slab by pressing it in the cutting direction while moving a pulley along the rails. The method for cutting and removing a concrete floor slab according to any one of claims 1 to 5,

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