JP7722656B2 - Deck cutting and separation system, and concrete deck and main girder cutting and separation method - Google Patents

Description

The present invention relates to a deck cutting and separation system used to cut and separate the joint between a concrete deck and a main girder, and a method for cutting and separating a concrete deck and a main girder using the deck cutting and separation system.

Bridge deck renewal work involves replacing deteriorated existing decks with new, more durable ones, and traffic must be blocked during this work. This requires traffic restrictions, such as road closures to general vehicles and various traffic restrictions, but the duration of these restrictions must be minimized to minimize the impact on existing traffic.

However, when replacing the deck with a new one, the existing deck must be removed from the existing girders, a removal process that takes a significant amount of time. In particular, removing the concrete around the shear stoppers of composite girders, which were streamlined by integrating the behavior of the deck and steel girders, took longer than with non-composite structures.

The inventors therefore proposed a construction method in which all cutting equipment is located under the deck, so that cutting of the existing deck for removal can begin as soon as construction traffic restrictions begin, minimizing the time spent restricting traffic during construction, and filed a patent application for this method. The cutting equipment in Patent Document 1 uses a wire saw to create a cutting surface parallel to the existing girder at the haunch, which is the joint between the existing deck and the existing girder, and then cuts and separates the existing deck and the existing girder.

Japanese Patent Application Laid-Open No. 2021-021227

According to Patent Document 1, because the work of cutting and separating the existing deck slab and existing girder is carried out beneath the existing deck slab, it is possible to shorten the traffic restriction period during deck renewal work. However, bridge structures are not necessarily uniform; for example, the existing deck slab may be installed at an angle perpendicular to the bridge axis relative to the existing girder, or the haunch, which is the joint between the existing deck slab and existing girder, may be formed low.

Therefore, when the cutting device is placed in a specified position, there is a risk that it may come into contact with the underside of the existing deck slab. In this case, it becomes necessary to perform additional, complicated work such as chipping the underside of the existing deck slab and cutting the lower reinforcement of the existing deck slab. For this reason, there has been a demand for auxiliary equipment to enable the cutting device to be used optimally under the existing deck slab, such as a device that can adjust the position of the cutting device to avoid contact with the existing deck slab.

Not limited to the cutting device of Patent Document 1, various cutting devices using wire saws are used to assist in the cutting and separating of existing deck slabs and existing girders. However, when a power supply is required for the device assisting in the cutting and separating work, including the power supply means makes the entire auxiliary device excessively large, occupying a large amount of work space, which can hinder work in the narrow space below the existing deck slab.

The present invention was developed in consideration of these issues, and its main purpose is to utilize auxiliary equipment to effectively utilize the narrow working space below the existing deck, and efficiently cut and separate the concrete deck and main girder.

To achieve this objective, the deck cutting and separation system of the present invention is a deck cutting and separation system for cutting and separating the joint between the concrete deck and main girder of a bridge, and is characterized by comprising a cutting device including a wire saw, a driven pulley around which the wire saw is hung, and a moving device on which the driven pulley is mounted and which forms a pair across the main girder and moves along the main girder below the concrete deck; an auxiliary device that assists the cutting device in cutting and separating the joint; and a rotational motion transmission mechanism that transmits the rotational motion of the driven pulley to the auxiliary device.

With the deck cutting and separation system of the present invention, the rotational motion of the driven pulley, which rotates as the wire saw travels in the extension direction, can be transmitted to the auxiliary device via a rotational motion transmission mechanism. This allows the auxiliary device to use the transmitted rotational motion as power, eliminating the need for a power supply means and allowing for more compact design. Therefore, the auxiliary device can be used to effectively utilize the narrow working space under the existing deck, making it possible to efficiently separate the concrete deck and main girder.

The deck slab cutting and separating system of the present invention is characterized in that the rotational motion transmission mechanism comprises a rotation source pulley that operates in conjunction with the driven pulley, a rotation receiving pulley that is equipped on the auxiliary device, and a rotational motion transmission belt that is wound around the rotation source pulley and the rotation receiving pulley.

With the deck cutting and separation system of the present invention, the rotational motion of the driven pulley, which rotates as the wire saw travels in the extension direction, is transmitted to the rotation receiving pulley of the auxiliary device via the rotation source pulley and the rotational motion transmission belt. This makes it possible to transmit rotational motion that rotates at the traveling speed of the wire saw to the auxiliary device.

The deck cutting and separation system of the present invention is characterized in that the auxiliary device includes a guide roller that rotates around an axis on whose outer periphery the rotation receiving pulley is installed, the guide roller is positioned near the joint with its axis aligned with the main girder, and the wire saw is in cross contact with a position facing the back surface of the concrete deck.

With the deck cutting and separation system of the present invention, the guide rollers provided on the auxiliary device can function as extension direction changers for the wire saw. This allows the attitude of the moving device, which needs to be positioned parallel to the wire saw, to be freely adjusted by changing the extension direction of the wire saw via the guide rollers. Therefore, even if there is a risk that the moving device may come into contact with the concrete deck, it is possible to avoid contact with the concrete deck by adjusting the attitude of the moving device, for example by tilting it, using an auxiliary device equipped with guide rollers.

Furthermore, if a rotational motion transmission mechanism is provided, a rotation receiving pulley can be installed on the guide roller, allowing the guide roller to rotate at the same speed as the wire saw travels in the extension direction. This prevents the outer circumferential surface from being cut by the traveling wire saw, while allowing the guide roller to perform its auxiliary function in the cutting and separation work.

The method for cutting and separating a concrete deck slab and a main girder of the present invention is a method for cutting and separating a concrete deck slab and a main girder using the deck slab cutting and separation system of the present invention, and is characterized in that the wire saw is run in the extension direction and moved along the guide roller in the extension direction of the main girder, forming a cut surface at the joint that is approximately parallel to the main girder.

The method for cutting and separating a concrete deck slab and main girder of the present invention makes it possible to efficiently cut and separate the concrete deck slab and main girder, even in the narrow working environment beneath the existing deck, by using guide rollers to prevent loosening of the wire saw, guide its movement direction, and even as a change in extension direction.

According to the present invention, by utilizing a cutting device and auxiliary device, including a moving device that moves along the main girder below the concrete deck, it is possible to effectively utilize the narrow working space below the existing deck and efficiently cut and separate the concrete deck and main girder.

1A to 1C are diagrams illustrating a cutting and separating operation performed by the cutting device according to an embodiment of the present invention. 1 is a diagram showing a deck slab cutting system according to an embodiment of the present invention. 1A and 1B are diagrams showing a guide device according to an embodiment of the present invention (part 1). 10A and 10B are diagrams showing a guide device according to an embodiment of the present invention (part 2); 1 is a diagram showing a rotational motion transmission mechanism according to an embodiment of the present invention; 3A and 3B are views showing a first front support device according to the embodiment of the present invention. 1 is a diagram showing the procedure for cutting and separating a concrete deck slab and a main girder using a deck cutting system according to an embodiment of the present invention. FIG.

This invention uses a slab cutting and separation system equipped with auxiliary equipment to perform the work of cutting and separating a concrete slab and main girder, which is one of the work processes carried out in road bridge slab renewal work. Below, we will explain in detail the slab cutting and separation system and the method for cutting and separating a concrete slab and main girder using the push-cut method as an example, with reference to Figures 1 to 7.

As shown in Figure 1, the bridge 400 has a steel main girder 401 and a concrete deck 402 installed on the main girder 401. A haunch 404 is formed on the underside of the concrete deck 402, forming the joint with the main girder 401. Furthermore, headed studs 4011 installed in the upper flange of the main girder 401 are embedded in the haunch 404. The headed studs 4011 are components that function as a shear stop for the concrete deck 402 in the approximately horizontal direction (mainly in the bridge axis direction).

When carrying out deck replacement work on the composite bridge 400, in which the concrete deck 402 and steel main girder 401 are integrated, a cutting device 100 equipped with a wire saw 10 is first used to form a cut surface 403 in the haunch portion 404.

Specifically, while the wire saw 10, which has penetrated the haunch portion 404 in a direction perpendicular to the bridge axis, travels in the extension direction, the first and second front support devices 40a, 40b that make up the cutting device 100 are moved along the main girder 401, as shown in Figure 2. The first and second front support devices 40a, 40b will be described in detail below, but each is equipped with first to eighth driven pulleys 41a-48a, 41b-48b around which the wire saw 10 is wound. As a result, the wire saw 10 moves in the bridge axis direction along the main girder 401 while being pressed against the position within the haunch portion 404 where the cutting surface 403 is to be formed.

Then, a cut surface 403 is formed in the haunch portion 404 by the wire saw 10, and the main girder 401 and the concrete deck 402 are cut and separated. After this, the concrete deck 402 that has been cut and separated from the main girder 401 is removed, and after preparatory work such as scraping is performed on the top surface of the upper flange of the main girder 401, a new deck is installed on top of the main girder 401.

The cutting surface 403 is formed in the haunch portion 404 using the above procedure, and the work of cutting and separating the main girder 401 and the concrete deck slab 402 is carried out using a deck slab cutting and separation system D, which includes the above-mentioned cutting device 100, as shown in Figure 2.

<<<Deck Cutting and Separation System>>
The deck cutting and separation system D comprises a cutting device 100 equipped with a wire saw 10, a guide device 300 that assists the cutting and separation work using the wire saw 10, and a rotational motion transmission mechanism 200 that transmits rotational motion from the cutting device 100 to operate the guide device 300.

The rotary motion transmission mechanism 200 does not necessarily have to be installed, and an auxiliary device other than the guide device 300 may be used as long as it assists in the cutting and separation work using the wire saw 10. Below, the details of the deck slab cutting and separation system D will be explained using the example of a case in which the guide device 300 is used as an auxiliary device and is operated using the rotary motion transmission mechanism 200.

<<Guide device>>
3(a), the guide device 300 includes a guide roller 301 against which the wire saw 10 crosses and abuts, a pair of cone members 303 connected to both ends of the guide roller 301, and a shaft 302 that supports the guide roller 301 via the cone members 303. The guide device 300 also includes an end jig 304, a suspender 305, and a bolt 306.

As shown in Figure 3(b), the shaft 302 is a core material inserted into the guide roller 301, and is a long rod having a shaft body 3021 and thin-diameter sections 3022 at both ends. Each thin-diameter section 3022 passes through a cone member 303 and is connected to an end jig 304, which is fastened to a hanging fixture 305 by a bolt 306.

The cone member 303 is a cylindrical body that is attached to the small-diameter portion 3022 of the shaft body 3021, and has a tapered surface 3031 formed on its outer circumferential surface that narrows toward the end facing the guide roller 301. A bearing 3032 is also fitted to the inner circumferential surface, allowing the cone member 303 to rotate freely around the shaft 302 when attached to the shaft 302.

The guide roller 301 is a cylindrical member that rotates around its axis, with the shaft 302 as its axis of rotation. The inner circumferential surfaces at both ends are formed with tapered surfaces 3011 that can abut against the tapered surfaces 3031 of the cone member 303. Therefore, when the shaft 302 is inserted through the guide roller 301 and the cone member 303 is attached to the narrow-diameter portion 3022 of the shaft 302, the tapered surfaces 3011 of the guide roller 301 and 3031 of the cone member 303 abut against each other, forming a wedge-like fit between the guide roller 301 and the cone member 303. As a result, the guide roller 301 and the cone member 303 can freely rotate while being supported by the shaft 302 via bearings 3032, as shown in Figure 3(c).

As shown in Figure 4(a), the above-mentioned guide device 300 is positioned near the haunch portion 404 so that the axis of the guide roller 301 is aligned with the main girder 401, and is installed on the underside of the concrete deck 402 via a hoisting device 305. The hoisting device 305 has multiple adjustment holes 3051, and the installation height of the guide roller 301 can be adjusted by using any of these adjustment holes 3051 to fasten the end jig 304 and the hoisting device 305 with bolts 306. The height of the guide roller 301 is adjusted to a height position where the wire saw 10 will not damage the main girder 401 and corresponds to the height position where the cutting surface 403 is formed.

Such guide rollers 301 function to prevent the wire saw 10 from damaging the main girder 401, as shown in Figure 2, to guide the wire saw 10 in the extension direction of the main girder 401 (bridge axis direction), and to prevent the wire saw 10 from loosening, as shown in Figure 1. In addition, they also function as a direction changer for the wire saw 10. In other words, as shown in Figures 1 and 4(b), with the guide roller 301 sandwiched between them, the haunch portion 404 side allows the wire saw 10 to extend approximately parallel to the cutting surface 403, while the cutting device 100 side changes the extension direction of the wire saw 10 so that it extends at the desired inclination angle.

Therefore, even if the concrete slab 402 is installed at an angle perpendicular to the bridge axis relative to the main girder 401, as shown in Figure 1, for example, the first front support device 40a that constitutes the cutting device 100 can be positioned near the underside of the concrete slab 402 without coming into contact with it.

In other words, the first front support device 40a, located on the side where the concrete slab 402 descends, cannot be positioned parallel to the height of the wire saw 10 penetrating the haunch portion 404 (the position where the cutting surface 403 is formed) because there is a risk of it coming into contact with the underside of the concrete slab 402. However, by using the guide device 300 to change the extension direction of the wire saw 10 so that it is inclined downward, the first front support device 40a can be positioned parallel to this inclined extending wire saw 10. This eliminates the need for work such as chipping into the underside of the concrete slab 402. It also prevents the wire saw 10 from coming into contact with and damaging the main girder 401.

On the other hand, the second front support device 40b, which is located on the side where the concrete deck slab 402 rises, can be positioned parallel to the height position (the position where the cutting surface 403 is formed) of the wire saw 10 that penetrates the haunch portion 404. Therefore, the guide roller 301, which is located between the haunch portion 404 and the second front support device 40b, only functions to prevent the wire saw 10 from damaging the main girder 401, to guide the wire saw 10 in the extension direction of the main girder 401 (the bridge axis direction), and to prevent the wire saw 10 from slackening.

This assists the cutting device 100 in cutting and separating the concrete deck 402 and the main girder 401, improving work efficiency in the narrow working environment below the concrete deck 402. As mentioned above, the guide roller 301 is rotatable around its axis, and is rotated by the wire saw 10 that crosses and abuts it. Consequently, its outer periphery is cut over time by the wire saw 10. Therefore, a cylindrical member with high hardness, such as a stainless steel pipe, iron pipe, or SPG pipe, is suitable as a material for the guide roller 301.

Furthermore, if the guide roller 301 has been worn down to the point where it can no longer perform the above-mentioned functions, it is advisable to replace the guide roller 301. To perform the replacement, as shown in Figure 3(c), remove and disassemble the bolt 306, end jig 304, and cone member 303. After that, pull out the existing guide roller 301 from the shaft 302 and reassemble using a new guide roller 301.

As described above, the guide roller 301 can be configured to rotate passively with the wire saw 10 by changing the material used and replacing it at the appropriate time, but it can also be actively rotated via the rotational motion transmission mechanism 200.

<<Rotational motion transmission mechanism>>
5, the rotational motion transmission mechanisms 200 are installed in pairs on both sides of the haunch portion 404. Details of the rotational motion transmission mechanisms 200 installed in the first front support device 40a and the guide device 300 will be described below as an example.

As shown in Figures 2 and 5, the rotational motion transmission mechanism 200 is a device that transmits the rotational motion of the fifth driven pulley 45a, of the first to eighth driven pulleys 41a to 48a provided on the first front support device 40a, to the guide device 300, and is equipped with a rotation receiving pulley 201, a rotation source pulley 202, a rotational motion transmission belt 203, and an adjustment pulley 204.

The rotation receiving pulley 201 and the rotation source pulley 202 are both belt pulleys, and the rotation receiving pulley 201 is fixed to the outer circumferential surface of the guide roller 301 by a fixing means such as welding.

As shown in Figure 5, the rotation source pulley 202 is mounted in a position that forms the same vertical plane as the fifth driven pulley 45a provided on the first front support device 40a of the cutting device 100, together with the aforementioned rotation receiving pulley 201. As shown in Figure 6, the rotation source pulley 202 and the fifth driven pulley 45a only need to be fixed coaxially. Alternatively, pulleys made of separate members may be fixed together, or a so-called double pulley with double grooves may be used.

The rotational motion transmission belt 203 is looped around the rotation receiving pulley 201, the rotation source pulley 202, and the adjustment pulley 204 (described later), and transmits the rotational motion of the rotation source pulley 202 to the rotation receiving pulley 201. Figure 4(c) shows an example of a so-called V-belt with a V-shaped cross section. For this reason, both the rotation receiving pulley 201 and the rotation source pulley 202 use belt pulleys with grooves that correspond to the V-belt.

The adjustment pulley 204 is a belt pulley similar to the rotation receiving pulley 201 and the rotation source pulley 202, and is positioned so that it forms the same vertical plane as the rotation receiving pulley 201 and the rotation source pulley 202, as shown in Figure 5. By being installed so that it can move within this vertical plane, it is possible to adjust the tension of the rotational motion transmission belt 203 that is wound around it.

With the above configuration, when the wire saw 10 travels in its extension direction, the fifth driven pulley 45a rotates. The rotational motion of the fifth driven pulley 45a is then transmitted to the rotation receiving pulley 201 via the rotation source pulley 202, which rotates in conjunction with the fifth driven pulley 45a, and the rotational motion transmission belt 203. As a result, the guide roller 301 to which the rotation receiving pulley 201 is attached rotates at the same speed as the wire saw 10 travels.

Therefore, during cutting and separating operations by the cutting device 100, the guide roller 301 actively rotates at the same speed even if the traveling speed of the wire saw 10 varies. This reduces the phenomenon in which the outer periphery of the wire saw 10 is cut and thinned by the wire saw 10, even when the wire saw 10 is in contact with the wire saw 10. Furthermore, in the second front support device 40b, as shown in Figure 2, the rotational motion of the fifth driven pulley 45b is transmitted to the guide roller 301 of the guide device 300.

The rotational motion transmission mechanism 200 configured as described above is not limited to the above configuration, as long as it can transmit the rotational motion of the fifth driven pulleys 45a, 45b generated by the wire saw 10 traveling in its extension direction to each of the paired guide devices 300. For example, a chain belt may be used for the rotational motion transmission belt 203, or the rotation receiving pulley 201, rotation source pulley 202, rotational motion transmission belt 203, and adjustment pulley 204 may be replaced by a configuration in which the rotational motion is transmitted by combining multiple gears.

However, considering ease of maintenance and the fact that it will be used in a work environment where the concrete deck slab 402 and the steel main girder 401 are cut and separated (for example, where dust and cooling water may be scattered), the use of a V-belt and V-pulley is preferable.

In addition to being applicable to the guide device 300, the rotational motion transmission mechanism 200 can also be used as an auxiliary device that assists in the work of cutting and separating the concrete deck slab 402 and main girder 401 using the cutting device 100. An example of an auxiliary device that can be used together with the rotational motion transmission mechanism 200 is a dust suction device that sucks up dust generated during cutting and separation.

In such cases, it is advisable to equip the auxiliary device with a conversion mechanism that converts the rotational motion transmitted from the rotational motion transmission mechanism 200 into another motion depending on the operation of the auxiliary device. Specifically, a mechanism that converts rotational motion into another motion, such as a link mechanism or crank mechanism that converts it into swinging motion or linear motion, is provided. In this way, the auxiliary device can operate using a motion different from the rotational motion transmitted from the rotational motion transmission mechanism as power.

Furthermore, the rotation source pulley 202 of the rotational motion transmission mechanism 200 may be installed on another pulley that rotates in a substantially vertical direction among the first to eighth driven pulleys 41a to 48a provided on the first front support device 40a, instead of the fifth driven pulley 45a.

Furthermore, the rotational motion transmission mechanism 200 may be arranged in a substantially horizontal plane, rather than a substantially vertical plane, as long as it is arranged on the same plane. In this case, instead of the fifth driven pulley 45a, any of the first to eighth driven pulleys 41a to 48a provided on the first front support device 40a that rotates in a substantially horizontal direction can be selected, and the rotation source pulley 202 can be installed on this pulley.

Details of the first and second front support devices 40a, 40b, which are equipped with the first to eighth driven pulleys 41a-48a, 41b-48b on which the above-mentioned rotation source pulley 202 is installed, are described below, along with an overview of the cutting device 100.

≪≪Cutting device≫≫
2, the cutting device 100 includes a wire saw 10 formed by processing a diamond saw wire into an endless shape, first and second rear support devices 50a, 50b, first and second front support devices 40a, 40b, a storage mechanism 30, and a drive mechanism 20, around which the wire saw 10 is hung. The cutting device 100 also includes a suspension frame 70 on which the drive mechanism 20 and the storage mechanism 30 are installed, and a pair of travel rails 60 that guide the travel direction of the first and second front support devices 40a, 40b and the first and second rear support devices 50a, 50b.

<First front support device 40a>
6, the first front support device 40a has first to eighth driven pulleys 41a to 48a around which the wire saw 10 is wound, and a pulley frame 49 that supports these. The pulley frame 49 has a front frame 491 and a rear frame 492 that are arranged in series, and the front frame 491 and the rear frame 492 are each provided with a moving body 493 that moves along the traveling rail 60 , and a feed device 494 that drives the moving body 493.

The feeder 494 may be provided on both the front frame 491 and the rear frame 492, and configured to synchronize them, or it may be provided on only one of them. If the feeder 494 is provided on only one of them, the rear frame 492 or the front frame 491, which does not have the feeder 494, may be configured to pull or push it.

In addition, as shown in Figure 1, angle adjustment members 495 are installed on the undersides of the front frame 491 and rear frame 492. This allows the front frame 491 and rear frame 492 to be tilted so that they are parallel to the wire saw 10 when the extension direction of the wire saw 10 is changed via the guide rollers 301 of the guide device 300.

Of the tilted front and rear frames 491 and 492, the front frame 491 is equipped with seventh and eighth driven pulleys 47a and 48a on its upper surface, as shown in Figure 2. These guide the wound wire saw 10 in a substantially horizontal direction. Meanwhile, the rear frame 492 is equipped with first and sixth driven pulleys 41a and 46a on its upper surface that guide the wire saw 10 in a substantially horizontal direction, as well as second through fifth driven pulleys 42a to 45a on its side surfaces that guide the wire saw 10 in a substantially vertical direction.

As a result, the wire saw 10 supplied from the first front support device 40b travels around the eighth, seventh, and sixth driven pulleys 48a, 47a, and 46a, and then, as shown in Figure 6, is redirected by the fifth driven pulley 45a and then wrapped around the fourth, third, second, and first driven pulleys 44a, 43a, 42a, and 41a.

<<Second front support device 40b>>
The second front support device 40b has the same configuration as the first front support device 40a, and includes first to eighth driven pulleys 41a to 48b. The pulley frame 49 that supports these pulleys also has the same configuration.

The wire saw 10 supplied from the first rear support device 50b to the second front support device 40b is first passed around the first driven pulley 41b, then changes direction and passes around the second to fifth driven pulleys 42b to 45b. It then changes direction and passes around the sixth to eighth driven pulleys 46b to 48b.

The details of the structure of the cutting device 100 equipped with the first front support device 40a and the first front support device 40b described above are given in Japanese Patent Application Laid-Open No. 2021-21227, but the outline is as follows.

<Outline of cutting device>
As shown in Figures 2 and 7(a), the pair of traveling rails 60 are installed in pairs with the haunch portion 404 in between, and include a guide portion 61 extending along the main girder 401, and a guide support 62 that supports the guide portion 61. The guide support 62 is detachably installed on the underside of the concrete floor slab 402, and suspends the guide portion 61. Also, as shown in Figures 7(b) and 7(c), the guide support 62 is slidably connected to the guide portion 61, and the guide portion 61 is connected to the guide support 62 so as to be movable in the height direction.

As shown in Figure 2, the suspension frame 70 comprises a horizontal member 71 suspended from the underside of the concrete slab 402. The horizontal member 71 is equipped with first and second twisting units 72, 74 around which the wire saw 10 is hung, a drive mechanism 20, and a storage mechanism 30. The first and second twisting units 72, 74 are mechanisms for twisting the running direction of the wire saw 10 from a vertical direction to a vertical direction or vice versa, and comprise horizontal pulleys 721, 741 and vertical pulleys 722, 742.

The storage mechanism 30 stores the excess length of the wire saw 10 while maintaining a constant tension, and also gradually unwinds the wire saw 10 as the cutting of the haunch portion 404 progresses and the first and second front support devices 40a, 40b move forward. Any structure may be used as long as it has these functions, but here, a pulley holder 31 is provided with multiple guide pulleys 32 that rotate vertically and are arranged in a vertical row.

The pulley holder 31 is suspended from the horizontal member 71 of the suspension frame 70, and a direction-changing pulley 33 that rotates vertically is installed next to it. The direction-changing pulley 33 supplies the wire saw 10, which is wound around the guide pulley 32, to the drive mechanism 20. The excess length of the wire saw 10 can be wound around the multiple guide pulleys 32 and direction-changing pulleys 33 provided in the storage mechanism 30 in any manner as long as a certain amount of tension is maintained.

The drive mechanism 20 applies a constant tension and high-speed rotational force to the wire saw 10, and is equipped with a drive pulley 21 around which the wire saw 10 is wound, a pulley guide 22 suspended from the suspension frame 70, and an elevating device 23 that moves up and down along the pulley guide 22. The drive pulley 21 of the elevating device 23 is located on the front side facing the main girder 401, and a drive unit 24 that rotates the drive pulley 21 is installed on the rear side. The drive pulley 21 is attached to the elevating device 23 via a horizontal shaft, and rotates vertically around the horizontal shaft to apply high-speed rotational force to the wound wire saw 10.

The first and second rear support devices 50a and 50b are located on the rearward side of the first and second front support devices 40a and 40b, respectively.

As shown in Figures 1 and 3, the first and second rear support devices 50a and 50b each have first to fourth driven pulleys 51a to 54a and 51b to 54b, around which the wire saw 10 is hung and rotates horizontally, and a pulley stand 55 that supports them. Details of the pulley stand 55 are omitted, but like the first front support device 40a and first front support device 40b, it also has a moving body that moves along the running rail 60 and a feed device that drives the moving body to move the first and second rear support devices 50a and 50b.

In the cutting device 100 configured as described above, the wire saw 10, whose excess length is stored in the storage mechanism 30, is hooked around the drive pulley 21. It is then hooked around the first and second driven pulleys 51a, 52a of the first rear support device 50a via the first twisting portion 72, and then around the first and fourth driven pulleys 51b, 54b provided on the second rear support device 50b. It is then hooked around the first to eighth driven pulleys 41b to 48b of the second front support device 40b, and passes through the haunch portion 404.

After passing through the haunch portion 404, it is hooked around the eighth to first driven pulleys 48a to 41a of the first front support device 40a, and then hooked around the third and fourth driven pulleys 53a, 54a of the first rear support device 50a, via the second torsion portion 74, to the storage mechanism 30.

As a result, when the first and second front support devices 40a, 40b are advanced along the pair of traveling rails 60, the wire saw 10 is constantly pressed against the haunch portion 404 in the direction in which the cutting surface 403 is to be formed. By operating the drive mechanism 20 in this state, the wire saw 10 travels in the extension direction and advances while expanding the area in which the cutting surface 403 is formed within the haunch portion 404.

<<<Method for cutting and separating concrete deck slabs and main girders using a deck slab cutting and separation system>>
The following describes the procedure for forming a cutting surface 403 in the haunch portion 404 and cutting and separating the concrete deck 402 and the main girder 401 using the deck cutting and separation system D equipped with the above-mentioned cutting device 100, rotational motion transmission mechanism 200, and guide device 300.

<<Preparation>>
First, as shown in Figure 2, the above-mentioned cutting device 100 is installed on the underside of the concrete floor slab 402. In Figure 2, since a pre-existing cutting surface 403 exists in the haunch portion 404, the wire saw 10 is passed through the haunch portion 404 using this cutting surface 403, and is then hooked around the first and second rear support devices 50a, 50b, the first and second front support devices 40a, 40b, the storage mechanism 30, and the drive mechanism 20. Simultaneously with or before or after these operations, the guide device 300 is assembled in the above-mentioned procedure and installed on the underside of the concrete floor slab 402.

At this time, the first front support device 40a tilts the front frame 491 using the angle adjustment member 495, preventing contact between the eighth driven pulley 48b and the concrete floor slab 402. Even if the first front support device 40a is tilted, the wire saw 10 changes its extension direction via the guide roller 301 of the guide device 300 as described above, so it does not affect the cutting operation. The height of the guide device 300 is adjusted so that the height position at which the guide roller 301 abuts against the underside of the concrete floor slab 402 is equal to the height position of the cutting surface 403.

A rotational motion transmission belt 203 is wound around a rotation source pulley 202 provided on the first front support device 40a of the cutting device 100 and a rotation receiving pulley 201 provided on the guide roller 301 of the guide device 300, and a rotational motion transmission mechanism 200 is provided on one side of the main girder 401. Similarly, a rotational motion transmission belt 203 is wound around a rotation source pulley 202 provided on the second front support device 40b of the cutting device 100 and a rotation receiving pulley 201 provided on the guide roller 301 of the guide device 300, and a rotational motion transmission mechanism 200 is provided on the other side of the main girder 401.

≪Cut surface formation work≫
After the above-described preparations are completed, the drive mechanism 20 of the cutting device 100 is operated to move the wire saw 10 in the extension direction. As the wire saw 10 moves, the fifth driven pulley 45a provided on the first front support device 40a rotates, and accordingly the rotation source pulley 202 of the rotational motion transmission mechanism 200 also rotates.

Therefore, the rotational motion transmission mechanism 200 can transmit rotational motion to the guide roller 301 via the rotational motion transmission belt 203 and the rotation source pulley 202. The rotational motion transmission mechanism 200 connected to the second front support device 40b functions in the same way, so that the guide rollers 301 of the pair of guide devices 300 on either side of the main beam 401 rotate in the same direction and at the same speed as the traveling direction of the wire saw 10.

In this state, as shown in Figure 7(a), the first and second front support devices 40a, 40b begin to travel, and the wire saw 10 forms a cutting surface 403 within the haunch portion 404, expanding its range in the extension direction of the main girder 401. Then, as shown in Figure 7(b), once the wire saw 10 reaches the vicinity of the suspender 305 of the guide roller 301 of the guide device 300 or the vicinity of the guide support 62 of the traveling rail 60, the travel of the first and second front support devices 40a, 40b is temporarily stopped, and the rotation of the wire saw 10 in the extension direction is interrupted.

As shown in Figure 7(c), the guide support 62 of the traveling rail 60 is moved to avoid interference with the wire saw 10, and the guide device 300 is moved forward in the direction of travel from the first front support device 40a. After this reloading operation is completed, the drive mechanism 20 is operated again, and the first and second front support devices 40a, 40b are caused to travel, and as shown in Figure 7(d), the wire saw 10 resumes forming the cut surface 403 on the haunch portion 404. These operations are repeated to form a predetermined range of cut surface 403.

With the above configuration, the guide device 300 can be used to adjust the posture of the first front support device 40a to avoid contact with the concrete slab 402, eliminating the need for the conventional process of chipping the underside of the concrete slab 402. Furthermore, the guide roller 301 rotates due to the rotational motion transmitted via the rotational motion transmission mechanism 200. Therefore, the guide device 300 does not require a separate drive mechanism, such as a motor, to provide power, allowing for compactness while reducing the phenomenon of thinning of the outer peripheral surface where the wire saws 10 intersect and come into contact.

In this way, the guide device 300 can be used to effectively utilize the narrow working space below the concrete slab 402, making it possible to efficiently carry out the work of forming the cutting surface 403.

The deck cutting and separation system and the method for cutting and separating a concrete deck and main girder of the present invention are not limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present invention.

For example, in this embodiment, the cutting device 100 uses a push-cutting method to form a cutting surface 403 on the haunch portion 404, and cuts and separates the concrete deck 402 and the main girder 401. However, this is not limited to this, and any cutting device that includes a wire saw 10 and a driven pulley around which the wire saw is hung can also be used as a pull-cutting method cutting device. Furthermore, the wire saw 10 may or may not be endless, and the wire saw 10 may or may not have an excess length.

Furthermore, the rotational motion transmission mechanism 200 and the guide device 300 do not necessarily have to be arranged in pairs on both sides of the main girder 401. Furthermore, the rotational motion transmission mechanism 200 and the guide device 300 may be provided on the first and second rear support devices 50a, 50b.

100 Cutting device 10 Wire saw 20 Drive mechanism 21 Drive pulley 22 Pulley guide 23 Lifting device 24 Drive unit 30 Storage mechanism 31 Pulley holder 32 Guide pulley 40a First front support device (moving device)
40b Second front support device (moving device)
41a to 48a: First to eighth driven pulleys 41b to 48b: First to eighth driven pulleys 49: Pulley stand 491: Front stand 492: Rear stand 493: Moving body 494: Feeding device 495: Angle adjustment member 50a: First rear support device (moving device)
50b Second rear support device (moving device)
51a to 54a First to fourth driven pulleys 51b to 54b First to fourth driven pulleys 55 Pulley base 60 Traveling rail 61 Guide portion 62 Guide support 70 Suspension base 71 Horizontal member 72 First torsion portion 721 Horizontal pulley 722 Vertical pulley 73 Direction-changing pulley 74 Second torsion portion 741 Horizontal pulley 742 Vertical pulley 200 Rotational motion transmission mechanism 201 Rotation receiving pulley 202 Rotation source pulley 203 Rotational motion transmission belt 204 Adjustment pulley 300 Guide device (auxiliary device)
301 Guide roller 302 Shaft 3021 Shaft body 3022 Thin diameter portion 303 Cone member 304 End jig 305 Lifting tool 306 Bolt 400 Bridge 401 Main girder 4011 Headed stud 402 Concrete deck 403 Cut surface 404 Haunch portion (joint)
D Deck cutting and separation system

Claims (4)

A deck cutting and separation system that cuts and separates a joint between a concrete deck and a main girder of a bridge,
a cutting device including a wire saw, a driven pulley around which the wire saw is wound, and a moving device provided with the driven pulley, which is paired with the main girder and moves along the main girder below the concrete deck;
an auxiliary device that assists the cutting device in cutting and separating the joint;
a rotational motion transmission mechanism that transmits the rotational motion of the driven pulley to the auxiliary device;
A deck cutting and separation system comprising: The deck cutting and separating system according to claim 1,
The rotational motion transmission mechanism is
a rotation source pulley that is interlocked with the driven pulley;
a rotation receiving pulley provided on the auxiliary device;
a rotational motion transmission belt wound around the rotation source pulley and the rotation receiving pulley;
A deck cutting and separation system comprising: The deck cutting and separating system according to claim 2,
The auxiliary device includes a guide roller that rotates around an axis on the outer circumferential surface of which the rotation receiving pulley is installed,
The guide roller is disposed near the joint with the axis aligned along the main girder,
A slab cutting and separation system characterized in that the wire saws are abutted crosswise at a position opposite the back surface of the concrete slab. A method for cutting and separating a concrete deck and a main girder using the deck cutting and separation system according to claim 3 ,
A method for cutting and separating a concrete deck and a main girder, characterized in that the wire saw is run in the extension direction and moved along the guide roller in the extension direction of the main girder, thereby forming a cutting surface at the joint that is approximately parallel to the main girder.