JP2016142097A - Portable hoist unit and horizontal member dismantling method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a portable hoist unit with high general-purpose properties, which can be installed in a compact general-purpose construction work vehicle, and a horizontal member dismantling method using the portable hoist unit.SOLUTION: A hydraulic jack, which has a tip of a rod provided with a pulley having a rope looped thereover, is adopted as hoist means of a portable hoist unit, and expansion/contraction of the hydraulic jack is transmitted to a bed via a rope. Thus, a long movement distance of the bed in a height direction is secured, and weight saving is achieved.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a portable lifting device and a method for disassembling a horizontal member using the portable lifting device.

  For example, when a so-called racket-type pier with two upper and lower piers is used for the bridge pier, a method to rebuild the existing pier is to build a pair of racket-type new piers with the existing pier sandwiched between them. The method is disclosed in Patent Document 1 and Patent Document 2.

  In the above method, since the existing pier is dismantled after the upper structure supported by the existing pier is replaced with the new pier, the rebuilding work can be carried out while the upper structure remains in service. This is a highly safe construction method.

  However, in Patent Document 1 and Patent Document 2 described above, it is clear how to dismantle the existing pier, particularly the upper pier beam, sandwiched between the new pier after the load of the superstructure is transferred to the new pier. Not been.

  In general, as a method of dismantling the horizontal members of the bridge such as a bridge pier and a bridge superstructure, a disassembly method using a center hole jack and a disassembly method using a hydraulic deck lift are widely known.

  In the dismantling method using the center hole jack, a pair of vents are constructed with a horizontal member to be dismantled between them, and a frame on which the center hole jacks are installed is installed on the pair of vents. Then, the lower end of the rod held by the center hole jack is fixed to the horizontal member, the horizontal member is cut, and the cut horizontal member is suspended on the center hole jack. Then, the horizontal member fixed to the rod is lowered while handing the rod with the center hole jack.

  On the other hand, in the dismantling method using the hydraulic deck lift, as disclosed in Patent Document 3, for example, the hydraulic deck lift is disposed below the horizontal member to be disassembled. Then, the deck of the hydraulic deck lift is raised and brought into contact with the lower surface of the horizontal member, the horizontal member is cut, and the cut horizontal member is placed on the deck. Thereafter, the horizontal member is lowered by lowering the deck.

JP 2008-303698 A JP 2012-237176 A JP 2011-208364 A

  After constructing a pair of racket-type new piers so as to sandwich the existing pier, the method of dismantling the existing pier in the method of dismantling the pier of the existing pier, applying a disassembly method using a center hole jack, There is no need to install a vent because the cradle with jacks can be bridged over the newly constructed pier and dismantled.

  However, since the upper structure exists above the existing bridge, the work with the center hole jack with many operation procedures is a work in a low head space, which is more complicated. Further, the work of handling the rod with the center hole jack not only takes a lot of time but is discontinuous, and there is also a concern that the horizontal member may fall, so it is necessary to take safety measures such as providing a support. Furthermore, it is necessary to carry the lowered horizontal member on the carry-out vehicle and carry it out, which increases the number of work steps.

  On the other hand, when the dismantling method using the hydraulic deck lift is applied, the work in the low head space above the existing pier can be greatly reduced. Further, since the hydraulic deck lift is mounted on the traveling body and used, it can be carried out without replacing the lowered horizontal member on the carrying-out vehicle.

  However, since a large hydraulic deck lift generally has a structure in which a plurality of heavy telescopic jacks are used to raise and lower the deck, the overall weight also increases. For this reason, a general construction vehicle such as a trailer cannot be employed as the traveling body, and a large special vehicle such as a dolly is employed as the traveling body.

  The hydraulic deck lift has a structure in which the deck and support base are integrated with the upper and lower ends of the telescopic jack. When placed on the traveling body, the total height is further increased.

  For this reason, for example, when disassembling the upper pier of an existing pier, use the upper structural road supported by the lower pier and attempt to carry out the cut upper pier while placing it on the hydraulic deck lift. Then, the case where it exceeds the building limit height of a road and cannot carry out is assumed.

  The present invention has been made in view of such problems, and its main purpose is to use a portable lifting device and a portable lifting device that are highly versatile and can be installed on a compact and general-purpose construction vehicle. It is to provide a method for disassembling a horizontal member.

  In order to achieve such an object, the portable lifting device of the present invention is a portable lifting device that is detachably mounted on a traveling body, and includes a bed on which a body to be lifted is placed and a lift that raises or lowers the bed. And a support frame on which the lifting mechanism is installed, and a hydraulic jack having a pulley with a rope attached to the tip of the rod is applied to the lifting mechanism, and one end of the rope is connected to the bed In addition, the other end is fixed to the stationary part, and the expansion and contraction of the hydraulic jack is transmitted to the bed through the rope.

  According to the portable lifting device of the present invention, since the expansion and contraction of the hydraulic jack is transmitted to the bed via a rope, it is not necessary to install the bed at the rod tip. Thereby, since the body length of the portable lifting device does not include the thickness of the bed member, it is possible to achieve a compact shape with a lower body length compared to a conventional hydraulic deck lift.

  Further, by using a hydraulic jack equipped with a rope-mounted pulley at the tip of the rod as the lifting mechanism, the bed can be moved up and down twice as much as the expansion and contraction of the hydraulic jack.

  As a result, when both the body length and the stroke length of the hydraulic jack are set to 1/2 of the distance to move the bed in the height direction, the lowest position of the bed is set near the base end height of the hydraulic jack. Can be set. For this reason, the lifted body can be lowered together with the bed to a height position near the base end of the hydraulic jack, and the lifted body is placed on the portable lifting device as compared with the conventional hydraulic deck lift. It is possible to further reduce the overall height at the time.

  In addition, since it is not necessary to use a heavy telescopic jack like a conventional hydraulic deck lift, the entire portable lifting device has a lightweight structure. Thereby, it is possible to employ a general construction vehicle such as a trailer widely used as a construction vehicle for the traveling body. For this reason, it is possible to significantly reduce the procurement cost of the vehicle and the fuel consumption related to transportation, thereby reducing the cost, and it is also possible to suppress pavement damage on the existing road by reducing the weight of the traveling body.

  In the portable lifting device according to the present invention, the bed is connected to the support frame via rolling prevention means, and the rolling prevention means expands and contracts following the lifting operation of the lifting mechanism. It is characterized by comprising.

  According to the portable lifting device of the present invention, even if some horizontal force is applied to the bed, the horizontal force is not transmitted to the hydraulic jack through the rope because the horizontal force is handled by the roll prevention means. Thus, it is possible to safely place the lifted body on the bed.

  The portable lifting device of the present invention comprises a recess on the lower surface of the bed, and when the lower surface of the bed and the upper surface of the support frame are brought into contact with each other, the recess of the bed It is a storage space.

  According to the portable lifting device of the present invention, when the hydraulic jack is shortened, it is possible to arrange the bed as low as a position where the bed abuts against the support frame without interference of the rolling prevention means.

  A horizontal member disassembly method according to the present invention is a horizontal member disassembly method in which a horizontal member supported by a column base is disassembled, and the portable lifting device is installed on a traveling body and moved below the horizontal member. A first step and a second step of raising the bed by the elevating mechanism and bringing the upper surface of the bed into contact with the lower surface of the horizontal member, and then cutting the horizontal member and placing it on the bed And a third step of unloading the horizontal member placed on the lifting device by the traveling body after the bed is lowered by the lifting mechanism.

  The horizontal member disassembly method of the present invention is characterized in that the horizontal member supported by the column base is a bridge pier beam supported by the pier column part.

  The horizontal member disassembly method of the present invention is characterized in that the horizontal member supported by the column pier is an upper pier beam supported by a pier column part of a racket-type pier having an upper pier and a lower pier. To do.

  According to the portable lifting device of the present invention, not only is the safety higher than when the horizontal member is suspended and disassembled, but a vent for placing a descent device used for lifting is installed. Therefore, work efficiency can be greatly improved.

  In addition, when disassembling the upper pier of the existing racket type pier, the above-mentioned portable lifting device is installed on a general-purpose construction vehicle such as a trailer. The supported superstructure road can be used. As a result, a series of operations from cutting to unloading of the upper pier can be carried out continuously, so that the work efficiency is improved and the working time can be greatly shortened.

  Compared with the case where the portable lifting device is installed on a large special vehicle such as a dolly, it does not occupy a wide road, so work using the upper structural road supported by the lower pier. Even in the case of performing, it becomes possible to perform work while securing a part of the road as a service route.

  According to the present invention, by reducing the height and weight of the portable lifting device, the portable lifting device is mounted on a general-purpose construction vehicle to be moved and operated. It is possible to transport the lifted body.

  In addition, since a series of dismantling operations from cutting to unloading related to the horizontal member supported by the column base can be performed by the portable lifting device, the working time can be greatly shortened.

It is a side view of a portable lifting device. It is a top view of the support stand in a portable lifting device. It is a top view of the bed in a portable lifting device. It is a figure which shows the state which mounted the to-be-lifted body in the portable raising / lowering apparatus. It is a figure which shows the side surface of the existing pier and a new pier. It is a figure which shows the detail of fall prevention work. It is a figure which shows the other example of the detail of fall prevention work. It is a figure which shows the dismantling method of the existing upper pier (the 1). It is a figure which shows the dismantling method of the existing upper pier (the 2). It is a figure which shows the dismantling method of the existing upper pier (the 3).

<Structure of portable lifting device>
Below, the portable lifting device 1 in this invention is explained in full detail with reference to FIGS.

  As shown in FIG. 1, the portable lifting device 1 is detachably installed on the traveling body 10 and can operate on the traveling body 10, and the bed 2 on which the lifted body 8 can be placed on the upper surface. And an elevating mechanism 3 that elevates and lowers the bed 2 and a support frame 4 that supports the elevating mechanism 3.

  As shown in FIG. 2, the support frame 4 extends in a direction orthogonal to the traveling direction of the traveling body 10 and a pair of beams 41 extending in the traveling direction of the traveling body 10, and connects the beams 41. A pair of girders 42 to be fixed are provided, and H beams are used for both the beam 41 and the girders 42. And the four raising / lowering mechanisms 3 are installed in the girder 42 of the support stand 4.

  As shown in FIG. 1, the elevating mechanism 3 includes a rope 31, a pulley 33 on which the rope 31 is hung, and a hydraulic jack 32 in which the pulley 33 is installed at the tip of a rod 321.

  As shown in FIG. 2, the hydraulic jacks 32 are arranged on both ends of the support frame 4 on the girders 42, and the ropes 31 are attached to the pulleys 33 as shown in FIG. Are connected to the bed 2 and the other end is fixed to the support frame 4.

  As shown in FIG. 3, the bed 2 extends in a direction orthogonal to the traveling direction of the traveling body 10 and a pair of beams 21 extending in the traveling direction of the traveling body 10, and is fixed so as to connect the beams 21. The beam 21 and the girder 22 are both made of H-section steel. The pair of beams 21 has a smaller arrangement interval than the pair of beams 41 constituting the support frame 4, and the length of the beam 21 is the arrangement interval of the pair of beams 42 constituting the support frame 4. It is formed smaller than.

  Thereby, the bed 2 is arranged so as to be surrounded by the four lifting mechanisms 3 as shown in FIG. 3, and when the hydraulic jack 32 is operated to extend the rod 321 as shown in FIG. Then, it is lifted by the rope 31 hung on the pulley 33 and raised with respect to the support frame 4.

  As described above, the portable lifting device 1 transmits the expansion and contraction of the hydraulic jack 32 to the bed 2 via the rope 31, so that it is not necessary to install the bed 2 at the tip of the rod 321. Thereby, since the member thickness of the bed 2 is not included in the main body length of the portable lifting device 1, the portable lifting device 1 can be formed into a compact shape with a low main body length as shown in FIG. Become.

  Further, since the bed 2 is transmitted with the expansion and contraction of the hydraulic jack 32 via the rope 31 hung on the pulley 33, the amount of movement in the height direction is twice as long as the rod 321 extends. Become. Therefore, in the present embodiment, the stroke length L2 of the rod 321 and the main body length L3 of the hydraulic jack 32 are set to ½ of the distance L1 at which the bed 2 is desired to move in the height direction.

  Thus, when the hydraulic jack 32 is operated to extend the rod 321 to the maximum, the bed 2 is lifted while being suspended, and reaches the same height position as the vicinity of the tip of the rod 321 as shown in FIG. . When the hydraulic jack 32 is shortened, the bed 2 is disposed at a height position near the base end of the hydraulic jack 32 as shown in FIG.

  Therefore, when the bed 2 on which the lifted body 8 is placed is lowered by the lifting mechanism 3, it is lowered to the vicinity of the base end of the hydraulic jack 32 which is the lowest lowered position, so that the lifted body 8 is placed on the bed 2. In this state, as shown in FIG. 4, a part thereof is within the main body height of the hydraulic jack 32.

  As described above, even when the body 8 is placed on the bed 2, the portable lifting device 1 in the state where the bed 2 is lowered by the lifting mechanism 3 is installed at the tip of the rod 321. The entire height of the lifted / lowered body 8 is not added to the total height of the portable lifting / lowering device 1 as in the case where the bed 2 is lifted directly by expansion / contraction of the hydraulic jack 32. Thereby, even if a conveyance path is a road with a low construction limit height, it becomes possible to install and transport the portable lifting device 1 on which the body 8 is mounted on the traveling body 10.

  Further, as described above, the expansion and contraction of the hydraulic jack 32 is transmitted to the bed 2 via the rope 31 hung on the pulley 33, so that the movement distance in the height direction of the bed 2 is extended by the rod 321. Since it can be doubled, it is not necessary to employ a heavy hydraulic jack such as a telescopic jack. As a result, the entire portable lifting device 1 has a lightweight structure, and a general-purpose construction vehicle such as a trailer can be adopted as the traveling body 10.

  In addition, as long as the portable lifting device 1 can be stably operated on the traveling body 10, any means may be used as a method for installing the portable lifting device 1 on the traveling body 10.

  In the present embodiment, as shown in FIG. 3, the brace member 5 is installed so as to connect the hydraulic jacks 32 adjacent to each other in the direction orthogonal to the traveling direction of the traveling body 10. However, the brace material 5 is not necessarily installed.

  Furthermore, although four lifting mechanisms 3 are installed on the support frame 4, the number thereof may be any, depending on the capacity of the hydraulic jack 32 to be used, the load of the lifted body 8 to be placed on the bed 2, etc. The quantity may be increased accordingly.

  In addition, the other end of the rope 31 constituting the elevating mechanism 3 is fixed to the support frame 4, but is not necessarily limited thereto. The other end of the rope 31 may be fixed to any fixed portion that does not move in the vertical direction with respect to the main body of the hydraulic jack 32.

  By the way, as shown in FIG. 1, the portable lifting device 1 is provided with a plurality of roll prevention means 6 for preventing the bed 2 suspended by the rope 31 from rolling.

  The roll prevention means 6 is composed of a bellows body in which a plurality of plate members 62 are connected in the vertical direction via a hinge member 61, and is vertically extendable and parallel to the plate surface of the plate member 62 when extended. It has the structure which has proof strength with respect to the horizontal force which acts on. Therefore, when it is arranged between the bed 2 and the support frame 4, as shown in FIG. 1, the roll prevention means in which the direction parallel to the plate surface of the plate 62 when extended is directed to the traveling direction of the traveling body 10. 6a and roll prevention means 6b in which the direction parallel to the plate surface of the plate member 62 at the time of extension faces the direction perpendicular to the traveling direction of the traveling body 10 are mixed and arranged.

  As a result, the horizontal force acting on the bed 2 in the traveling direction of the traveling body 10 acts on the roll prevention means 6a and the horizontal force acting on the bed 2 in a direction perpendicular to the traveling direction of the traveling body 10. The force is borne by the roll prevention means 6b.

  In the present embodiment, two roll prevention means 6a and two roll prevention means 6b are arranged, respectively, but the number thereof may be any.

  Further, as shown in FIG. 4, a storage space 9 for storing the folded roll prevention means 6 is formed between the bed 2 and the support frame 4, and the bed 2 is mounted on the base of the hydraulic jack 32. Even if it is lowered to the vicinity of the end and brought into contact with the support frame 4, the roll prevention means 9 is configured not to be an obstacle.

  Specifically, as shown in FIG. 3, a fixing member 7 c extending in a direction orthogonal to the traveling direction of the traveling body 10 is installed so as to connect both between the pair of beams 21 of the bed 2. At the same time, as shown in FIG. 2, the support frame 4 is also connected between a pair of beams 41, and a fixing member 7d is installed below the fixing member 7c provided on the bed 2 so as to be parallel thereto. .

  Further, as shown in FIG. 3, a fixing member 7a extending in the advancing direction of the traveling body 10 is installed so as to connect both between adjacent beams 22 of the bed 2, and as shown in FIG. In addition, a fixing member 7b is installed below the fixing member 7a provided on the bed 2 so as to be parallel to the fixing member 7d on the support frame 4 so as to be connected between the adjacent fixing members 7d.

  At this time, as shown in FIG. 1, the height of the fixing members 7 a and 7 c installed on the bed 2 is set to ½ of the beam of the beam 21 constituting the bed 2, and is sandwiched between the beams 21 of the bed 2. A recess is formed on the inside of the lower surface. Further, the heights of the fixing members 7 b and 7 d installed on the support frame 4 are also set to a half height of the beam 41 of the beam 41 constituting the support frame 4.

  Thereby, when the bed 2 is lowered, the lower surface of the beam 21 constituting the bed 2 comes into contact with the upper surface of the fixing member 7d installed on the support base 4 as shown in FIG. At that time, the fixing members 7 a and 7 c installed on the bed 2 are lower in height than the beams 2 forming the bed 2, and thus do not come into contact with the fixing members 7 c and 7 d installed on the support frame 4. Therefore, a space is formed between the recess on the lower surface of the bed 2 and the support frame 4.

  Therefore, the space formed in the concave portion is used as a storage space 9 for the roll prevention means 6, and the roll prevention means 6a is disposed between the fixing members 7a and 7b so that the upper end is fixed to the fixing member 7a and the lower end is fixed. It fixes to the member 7c. Similarly, the roll prevention means 6b is disposed between the fixing members 7c and 7d, and the upper end is fixed to the fixing member 7c and the lower end is fixed to the fixing member 7d.

  In the present embodiment, the height of the fixing members 7a and 7c installed on the bed 2 is ½ the beam formation of the beam 21, and the height of the fixing members 7b and 7d installed on the support frame 4 is the beam 41. However, the height is not necessarily limited to this. A space in which a storage space 9 can be formed between the fixing member 7a installed on the bed 2 and 7b installed on the support frame 4, and between the fixing member 7b installed on the bed 2 and 7c installed on the support frame 4. As long as can be formed, the size may be any.

  With the above-described configuration, the bed 2 is disposed in the vicinity of the proximal end of the hydraulic jack 32 as shown in FIG. 4 when lowered by the lifting mechanism 3, and the roll prevention means 6 includes the bed 2, the support frame 4, and the like. Are stored in a folded state in a storage space 9 formed therebetween.

  As shown in FIG. 1, the roll prevention means 6 stored in the storage space 9 extends following the extension of the hydraulic jack 32 when the elevator mechanism 3 moves up. As a result, the upward vertical force applied from the hydraulic jack 33 is smoothly transmitted to the bed 2 via the rope 31, and the bed 2 rises with respect to the support frame 4.

  On the other hand, when a horizontal force is applied to the bed 2 due to some influence such as movement by the traveling body 10 or wind, the rolling prevention means 6 bears this, so that the horizontal force is applied via the rope 31 to the hydraulic jack. 33 is not transmitted.

  As described above, the portable lifting device 1 can lift and lower the body 8 placed on the bed 2 in a stable state while preventing rolling, and also when the traveling body 10 carries it out. It becomes possible to prevent rolling.

<Disassembly method of horizontal member using portable lifting device>
The disassembly method for disassembling the horizontal member supported by the column base using the portable lifting device 1 having the above-described configuration will be described in detail.
In the present embodiment, a bridge pier is taken as an example. In particular, a case of a so-called racket type pier is taken as an example, and the case of disassembling the upper pier supported by the pier column of an existing pier is referred to FIGS. And will be described in detail. Moreover, the trailer generally used as a construction vehicle is employ | adopted for the traveling body 10 which mounts the portable raising / lowering apparatus 1. FIG.

  As shown in FIG. 8, the racket-type existing pier 11 is installed at each of the existing pier column 12, the existing lower pier beam 13 supported by the existing pier column 12, and both ends of the existing lower pier beam 13. An existing upper pier column 14 and an existing upper pier beam 15 supported by the existing upper pier column 14 are configured. Further, the existing lower pier 13 supports the upper structure 16 and the existing upper pier 15 supports the upper structure 17, and both the upper structures 16 and 17 are used as roads.

  Therefore, in the present embodiment, when disassembling the existing upper pier 15, the portable lifting device 1 is loaded using the road on the upper structure 16 supported by the existing lower pier 13, and the existing upper pier 15 Dismantle.

<Pretreatment process>
First, as shown in FIG. 5, a pair of new piers 18 are constructed so as to sandwich the existing pier 11 in the bridge axis direction X, and the loads of the upper structures 16 and 17 are transferred to the new pier 18.
The loads on the upper structures 16 and 17 do not necessarily have to be transferred to the newly installed pier 18; for example, a generally-used vent method is employed, and a vent is disposed in the vicinity of the existing pier 11 to receive the load. You may change.
In this embodiment, the pier column of the new pier 18 is integrated with the existing pier column 12. However, the present invention is not necessarily limited to this, and the pier column of the new pier 18 is connected to the existing pier column 12. It may be constructed separately.

Next, a fall prevention work is applied to the existing upper pier 15.
Specifically, as shown in FIG. 6, a suspension base 21 is hung on the top end of a new pier 18 arranged in a pair in the bridge axis direction X, and a suspension jig 22 is attached to the suspension base 21. Install. The hanging jig 22 includes a bolt member 221 penetrating the suspension stand 21 in the vertical direction, and a receiving stand 222 installed at the lower end of the bolt member 221, and the receiving stand 222 is newly provided in a pair in the bridge axis direction X. It arrange | positions in the position which contact | abuts the existing upper bridge pier 15 pinched by the pier 18. As shown in FIG.

  On the other hand, a so-called post-construction anchor 23 is installed on the existing upper pier 15, and the post-construction anchor 23 is passed through a hole (not shown) provided in the pedestal 222 to be fastened and tensioned, whereby the cradle 222 is installed. Both are fastened in contact with the upper pier 15.

  The installation position of the post-construction anchor 23 is not necessarily limited to the top end of the existing upper pier 15 but may be installed on the side surface of the existing upper pier 15 as shown in FIG. .

  In addition, the fall prevention work described above determines the number of divisions when the existing upper pier 15 is cut and carried out in advance, and as shown in FIG. After that, positioning is performed so that the construction anchor 23 is arranged. It should be noted that the number of divisions of the existing upper pier 15 is such that the horizontal dimension of the divided pieces 151 is within the loadable width in consideration of the loadable width of the portable lifting device 1 used when carrying out the divided pieces 151. Set it.

<First step>
As shown in FIG. 8, the portable lifting device 1 is placed on the road on the upper structure 16 supported by the existing lower pier 13, and is arranged immediately below the planned position that becomes the split piece 151 after cutting in the existing upper pier 15. To do.

  In the present embodiment, the work is performed while the right lane of the road on the upper structure 16 supported by the existing lower pier 13 is used as the service route 25. First, the left side of the existing upper pier 15 is set to 3 The body is divided into divided pieces 151. Of the three divided pieces 151, the portable lifting device 1 is stopped immediately below each of the divided pieces 151 </ b> A and 151 </ b> C located on both sides.

  In addition, according to work time, work space, etc., the divided pieces 151A, 151B, 151C may be removed one by one, or three can be removed simultaneously. However, when removing three bodies at the same time, the distance between the portable lifting devices 1 that stop next to each other is narrowed, so that the split pieces 151A and 151C are disassembled in advance in consideration of workability and safety. To do.

  Further, in the present embodiment, a support 24 is installed for safety under the divided piece 151B that is removed and removed from the three divided pieces 151A, 151B, 151C. However, since the fall prevention work is performed, it is not always necessary to provide the support 24.

  Furthermore, the existing upper bridge pier 15 located above the service line 25 in use during the construction becomes cantilevered when the divided pieces 151A, 151B, 151C are removed. For this reason, in consideration of safety, it is advisable to apply a fall prevention work similar to that of the split piece 151 although not shown.

<Second process>
Next, as shown in FIG. 9A, the lifting mechanism 3 of the portable lifting device 1 is operated to raise the bed 2, and the upper surface of the bed 2 is divided into pieces 151 </ b> A after cutting at the existing upper pier 15. , 151C is brought into contact with the lower surface of the planned position.

  At this time, when the pavement surface of the road on the upper structure 16 supported by the existing lower pier 13 does not have a plane parallel to the lower surface of the existing upper pier 15 such as a transverse gradient is provided. There are many. Therefore, when the existing upper bridge pier 15 cannot be brought into contact with the bed 2 of the portable lifting device 1 in a stable state, it may be adjusted by appropriately interposing a cushioning material 26 as shown in FIG.

  Further, in the present embodiment, as shown in FIG. 1, the new bridge pier 18 that forms a pair with the length in the traveling direction of the traveling body 10 in the portable lifting device 1, that is, the length in the bridge axis direction X can be included. Thus, when the bed 2 is brought into contact with the lower surface of the existing upper pier 15, the lifting mechanism 3 is configured not to contact the newly installed pier 18. However, the length of the portable lifting device 1 is not necessarily limited to that described above. For example, the length of the portable lifting device 1 is set to be short enough to include the existing upper bridge pier 15 and the bed is placed via a buffer material 26 having a predetermined height. 2 may be brought into contact with the lower surface of the existing upper pier 15 so that the elevating mechanism 3 does not contact the newly installed pier 18.

  Then, after confirming that the bed 2 is stably in contact with the planned positions to be the divided pieces 151A and 151C after cutting in the existing upper pier 15, the existing upper pier 15 is cut and the suspension jig 22 The bolts 221 are removed, and the divided pieces 151A and 151C are placed on the bed 2.

<Third process>
Next, after confirming that the load of the divided pieces 151A and 151C has been transferred to the bed 2, as shown in FIG. 9B, the lifting mechanism 3 is operated to move the divided pieces 151A and 151C together with the bed 2. Lower. Thereafter, the split pieces 151 </ b> A and 151 </ b> C are carried out together with the portable lifting device 11 by the traveling body 10.

  Thereafter, the support 24 of the split piece 15B is removed as shown in FIG. 10 (a), and then the portable lifting device as shown in FIG. 10 (b) is performed in the first to third procedures described above. 1 and the divided piece 151B are carried out using the traveling body 10.

  After carrying out the above procedure on all existing piers 11 to be removed, the service line 25 is changed to the left one lane, and the right side portion of the existing upper pier beam 15 which is cantilevered is replaced with the first To dismantle according to the third procedure.

All the existing upper piers 15 are removed by the above process.
Thereafter, the upper pier column 14 is removed and the existing lower pier beam 13 is also removed by using, for example, a dismantling method using a conventional center hole jack.

  The existing lower pier 13 can be dismantled in the same procedure as the existing upper pier 15 according to the first to third steps described above using the portable lifting device 1. In this case, the suspension base 21 is hung on the top end of the lower pier beam of the newly constructed pier 18 and a suspension jig 22 is installed on the suspension base 21.

  As described above, in the method of disassembling the horizontal member in the present invention, the portable lifting device 11 is installed on the traveling body 10 made of a trailer, and thus the work is supported by the existing lower bridge pier 13 having a low building limit height. A road on the superstructure 16 can be used. As a result, a series of operations from cutting to unloading of the existing upper pier 15 can be carried out continuously, so that the working efficiency is greatly improved and the working time can be greatly shortened.

  In addition, since the portable lifting device 1 is installed on the traveling body 10 made of a trailer, the work is not performed so as to occupy a wide road width as in the case where a special vehicle such as a dolly is employed for the traveling body 10. For this reason, even when working using the road on the upper structure 16 supported by the existing lower bridge pier 13, it is possible to perform the work while securing a part of the road as the service route 25. .

  The portable lifting device 1 and the method for disassembling the horizontal member using the portable lifting device 1 are not limited to the above embodiment, and various modifications are possible without departing from the spirit of the present invention. is there.

  For example, in the present embodiment, in the dismantling method of the horizontal member using the portable lifting device 1, the dismantling method was described in detail by taking the existing upper pier 15 and the existing lower pier 13 of the existing pier 11 as horizontal members as examples. . However, the horizontal member is not necessarily limited thereto, and can be applied to the upper structures 16 and 17 of the existing pier 11 as long as the horizontal member is supported by the column base.

DESCRIPTION OF SYMBOLS 1 Portable lifting device 2 Bed 3 Elevating mechanism 4 Support stand 5 Brace material 6 Rolling prevention member 7 Fixing member 8 Elevated body 9 Storage space 10 Traveling body 11 Existing pier 12 Existing pier pillar 13 Existing lower pier beam 14 Existing upper pier Pillar 15 Existing upper pier beam 151 Split piece 16 Upper structure 17 Upper structure 18 New pier 21 Suspension stand 22 Suspension jig 221 Bolt 222 Receiving base 23 Post-work anchor 24 Support 25 Service line 26 Buffer material

Claims (6)

A portable lifting device that is detachably installed on the traveling body,
A bed on which a body to be lifted is placed, a lifting mechanism for raising or lowering the bed, and a support frame on which the lifting mechanism is installed,
Applying to the lifting mechanism a hydraulic jack equipped with a pulley with a rope at the tip of the rod, connecting one end of the rope to the bed and fixing the other end to the stationary part, A portable lifting device that transmits expansion and contraction of a hydraulic jack to the bed. The portable lifting device according to claim 1,
The bed is connected to the support frame via roll prevention means;
The portable lifting device characterized in that the roll prevention means comprises a bellows body that expands and contracts following the lifting operation of the lifting mechanism. The portable lifting device according to claim 2,
A protrusion projecting downward on the outer edge of the lower surface of the bed;
A gap between the lower surface of the bed and the upper surface of the support frame, which is formed when the protruding portion of the bed and the upper surface of the support frame are brought into contact with each other, serves as a storage space for the roll prevention means. A portable lifting device. A horizontal member dismantling method for dismantling a horizontal member supported by a column base,
A first step of installing the portable lifting device according to any one of claims 1 to 3 on a traveling body and moving the portable lifting device below the horizontal member;
A second step of raising the bed by the elevating mechanism and bringing the upper surface of the bed into contact with the lower surface of the horizontal member, and then cutting the horizontal member and placing it on the bed;
A third step of unloading the horizontal member placed on the lifting device by the traveling body after the bed is lowered by the lifting mechanism;
A method for disassembling a horizontal member, comprising: In the dismantling method of the horizontal member according to claim 4,
A horizontal member disassembly method, wherein the horizontal member supported by the column base is a bridge pier beam supported by the pier column part. In the dismantling method of the horizontal member according to claim 4,
A horizontal member dismantling method, wherein the horizontal member supported by the column pier is an upper pier beam supported by a pier column part of a racket-type pier having an upper pier and a lower pier.

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