JP6713420B2 - Rebar cage relocation device - Google Patents

Description

The present invention relates to a rebar cage moving device.

Conventionally, as a technique in such a field, an overhanging construction method described in Patent Document 1 below is known. In this method, the mobile work vehicle is extended from the tip of the existing bridge girder of the bridge, and the box girder block made of reinforced concrete is extended from the tip of the existing bridge girder. By repeating such overhanging construction, the bridge girder will be gradually expanded. The reinforcing bars embedded in the box girder block are assembled in advance as a reinforcing bar cage, the reinforcing bar cage is hung and moved using a hoist or the like, and is installed at the concrete pouring position of the box girder block.

Japanese Patent Laid-Open No. 11-021820

In the method of assembling the reinforcing bar cage first by the overhanging construction method, the reinforcing bar cage is assembled at the assembly workshop set in front of the planned position of the box girder block, and the assembled reinforcing bar cage is moved from the main frame of the mobile work vehicle to the trolley. It is also conceivable to suspend the trolley along the trolley rail and move it to the planned construction position. However, when a bridge girder that widens as it goes forward is under construction, the rails of the mobile work vehicle are laid so as to open in a V shape in a plan view. The pair of main frames that move on each rail are also arranged in a V shape in a plan view, and the pair of trolley rails provided in each main frame are also arranged in a V shape. That is, the width between the trolley rails becomes larger toward the front.

Therefore, at the position corresponding to the assembly work shop, the width between the trolley rails is larger than the width between the trolley rails at the planned construction position. On the other hand, the width of the rebar cage assembled in the assembly workshop corresponds to the width of the planned construction position. Therefore, in the assembly workshop, the width of the main frames is larger than that of the rebar cage to be assembled. Then, when the reinforcing bar cage is hung from the main frame at the assembly workshop, the hanging material does not become vertical and the sling part of the reinforcing bar cage is pulled diagonally upward. Will be added. The same problem also occurs in the case of constructing a bridge girder whose width becomes smaller toward the front in the overhanging construction method.

When the reinforcing bar cage is deformed by the above-mentioned force applied to the reinforcing bar cage, irreversible deformation may occur in the binding portion between the reinforcing bars, and the deformation of the entire reinforcing bar cage may remain. Further, the above-mentioned binding portion may be damaged and the binding work may have to be redone.

In view of such problems, an object of the present invention is to provide a rebar cage moving device that suppresses deformation of the rebar cage.

The rebar cage transfer device of the present invention is a rebar basket transfer device that moves a rebar cage embedded in a box girder block constructed by a bridge overhanging construction method to a construction planned position of the box girder block by suspending it with a mobile work vehicle. The box girder block has a bottom slab and a pair of opposing side walls provided so as to rise from both end edges of the bottom slab, and the mobile work vehicle is a plan view of the existing box girder block. Having a pair of main frames arranged along each of the pair of side walls, the reinforcing bar basket includes a bottom plate reinforcing bar portion embedded in the bottom plate and a pair of opposing side wall reinforcing bar portions embedded in the side wall. Having a pair of trolley rails that are provided on each main frame and extend along the extension of the side wall in plan view, a trolley that is guided and moved by the trolley rails, and a rebar cage The suspension device is disposed above each of the pair of side wall reinforcing bars, is connected to each of the side wall reinforcing bars, and is provided with a pair of suspending devices that are suspended and supported from the trolley via suspension members. A reinforcing bar cage transfer device having a slinging member to which materials are connected, and the slinging member is displaceable relative to a reinforcing bar cage along a side wall reinforcing bar portion in a plan view.

Further, the suspension member may have a swivel mechanism that allows the relative rotation of the trolley and the sling member about the vertical axis.

In addition, the suspending device includes a vertical beam member that includes two channel members that are symmetrically arranged with the outer surfaces of the webs facing each other and that extends along the sidewall rebar portion in a plan view, and the sling member includes Equipped with H steel having a web sandwiched between channel members and upper and lower flanges hooked on the upper and lower surfaces of the vertical beam member, and the H steel sliding on the channel member. May be displaceable along the side wall reinforcing bars.

Further, the suspending device includes a guide beam member that guides the sling member, an auxiliary beam member that extends parallel to the guide beam member, a guide beam member, and a guide beam member that extends in a direction substantially orthogonal to the guide beam member. And a horizontal beam member rigidly connected to the beam member and the auxiliary beam member may be used to form a cross beam structure.

ADVANTAGE OF THE INVENTION According to this invention, the suspension method and suspension structure which suppress the deformation|transformation of a reinforcement cage can be provided.

(A) is a side view of a bridge to which the rebar cage moving device of this embodiment is applied, and (b) is a plan view thereof. It is a side view which shows a mobile work vehicle. It is a front view showing the important section of a mobile work vehicle. It is a top view showing the important section of a mobile work vehicle. (A)-(d) is a side view which shows in order the procedure of overhang construction by a mobile work vehicle. (A) is sectional drawing which shows a rebar cage, (b) is sectional drawing which shows the state which attached the jig for suspension to a rebar cage. (A), (b) is sectional drawing which expands and shows the vicinity of the bottom slab reinforcement of a reinforcement cage. It is sectional drawing which expands and shows the intersection part of the bottom slab reinforcement of a reinforcement cage, and a side wall reinforcement. It is sectional drawing which expands and shows the upper vicinity of the side wall reinforcement of a reinforcement cage. (A) is a perspective view showing a single pipe pipe and a bent portion, and (b) is a side view showing the single pipe pipe and a bent portion sandwiched. It is a figure which shows the state in which the rebar cage was hung by the trolley. It is an exploded perspective view showing a vertical beam material of a suspending device. (A), (b) is a top view which shows the positional relationship of a mobile work vehicle, a rebar cage, etc. in a front end.

Hereinafter, an embodiment of a rebar cage moving device according to the present invention will be described in detail with reference to the drawings.

First, an overhanging construction method of the bridge 100 to which the trolley device 151 as the rebar cage moving device of the present embodiment is applied will be described. The bridge 100 shown in FIG. 1 is a structure made of concrete, for example, a continuous ramen box girder bridge. The bridge 100 includes a plurality of bridge piers 101 standing upright from the ground, a pillar head 103 provided on each bridge pier 101, and a bridge girder 104 bridged between the pillar heads 103 and 103. The bridge girder 104 has two box girders 105 extending substantially parallel to the bridge axis direction, and an overhanging floor slab 107 provided on the box girder 105. In the following description, as shown in the drawings, X, Y, and Z may be used with the vertical direction as the Z direction, the bridge axis direction as the Y direction, and the bridge axis orthogonal direction as the X direction.

As shown in FIG. 3, one box girder 105 extends substantially horizontally at a bottom plate 105a extending substantially horizontally, two webs 105b standing substantially vertically upward from both ends of the bottom plate 105a, and an upper end of the web 105b. And the existing upper plate 105c, and the cross-sectional shape of the box girder 105 orthogonal to the bridge axis direction is a hollow rectangle. The box girder 105 after completion may extend in the horizontal direction or may extend in a direction inclined with respect to the horizontal direction. Further, the box girder 105 after completion may extend straight in a plan view, or may extend curvedly. In this embodiment, as shown in FIGS. 1A and 1B, the case where the completed box girder 105 extends straight in the horizontal direction will be described as an example. Further, as shown in FIG. 1(b), the box girder 105 extends in the direction perpendicular to the bridge axis as the box girder 105 moves away from the column head 103 (the column head 103 on the left side in the figure) that starts the overhanging construction method in the present embodiment. It has been widened.

The box girder 105 is constructed one block at a time from the column head 103 by an overhanging construction method, and gradually extends in the bridge axis direction by one block toward another adjacent column head 103. Actually, the erection erection in two directions is performed from one stilt head 103 in opposite directions, but in the present embodiment, only the construction of erection erection in one direction will be described. Below, the direction in which the box girder 105 is extended by the overhanging construction method is defined as “front”, and words such as front and rear are used.

Further, a portion of one block which is a construction unit of the box girder 105 is referred to as a "box girder block P". Further, when distinguishing each box girder block P, the box girder block P1 of the first block, the second block,... P2,..., Box girder block Pn.

As shown in FIG. 2, a plurality of rails 123 are laid on the upper surface of the existing part of the bridge girder 104 (hereinafter referred to as “bridge girder existing part 104a”), and the rail 123 extends to the front end of the bridge girder existing part 104a. .. A mobile work vehicle 121 used in the overhanging construction method is installed on the rail 123, and the mobile work vehicle 121 is configured to be movable on the rail 123 in the bridge axis direction.

The mobile work vehicle 121 is fixed to the front end of the rail 123, and projects the box girder block Pn from the front end of the existing part of the bridge girder 104a. Then, the rail 123 is extended on the completed box girder block Pn. Then, the mobile work vehicle 121 is moved forward to the tip of the rail 123, and the box girder block P(n+1) is overhanging. By repeating the above, the existing portion of the bridge girder 104a gradually expands.

(Mobile work vehicle)
Next, the mobile work vehicle 121 will be described with reference to FIGS.

As shown in FIG. 2, the mobile work vehicle 121 includes a wagon frame 130 that is movable on the rail 123 in the bridge axis direction, and an upper beam 137 arranged on the wagon frame 130. The wagon frame 130 and the upper beam 137 are formed by joining a plurality of H-shaped steels, for example. In the present specification, the wagen frame 130 is a concept including what is called a “traveler”.

As shown in FIGS. 2 and 3, the wagon frame 130 includes four main frames 131 arranged substantially parallel to each other in the direction perpendicular to the bridge axis. Each main frame 131 is formed of a parallelogram-shaped truss structure surface, and the truss structure surface is arranged along the vertical plane. In the present specification, the main frame 131 is a concept including what is called a “main truss”. A rear end bottom portion of the main frame 131 is fixed to the rail 123 by an anchor jack 133, and a front end bottom portion of the main frame 131 is supported on the rail 123 by a main jack 135.

The upper beam 137 is installed on these four main frames 131. The upper beam 137 includes two horizontal members 137a and 137b extending in a direction perpendicular to the bridge axis and three connecting beams 137c extending in the bridge axis and connecting the horizontal members 137a and 137b. And, and are formed in a cross beam shape. The horizontal member 137a is arranged substantially vertically above the main jack 135. The horizontal member 137b is arranged in front of the front end of the existing portion of the bridge girder 104a. An extension beam 132 that extends further forward is provided at the front end of the upper portion of the main frame 131. A horizontal member 134 extending in the direction perpendicular to the bridge axis is bridged between the two central portions of the four extension beams 132 arranged in the direction perpendicular to the bridge axis.

At the time of overhanging construction, the portion of the main frame 131 in front of the main jack 135 is arranged to extend in front of the front end of the existing portion of the bridge girder 104a. Further, in consideration of the supporting strength of the existing portion of the bridge girder 104a, each main frame 131 is arranged at a position vertically above each web 105b of the box girder 105.

The mobile work vehicle 121 includes a form supporting member 139 that is suspended by the wagon frame 130, and a rebar tip assembly device 141 that is suspended by the upper beam 137 and the horizontal member 134. The formwork support portion 139 is arranged so as to project to the front side of the front end of the existing part of the bridge girder 104a, and the rebar tip assembly device 141 is arranged further forward of the formwork support portion 139.

(Form support part)
The formwork supporting portion 139 has a formwork receiving beam 143 suspended from the upper beam 137 via a plurality of suspending members 142. The formwork receiving beam 143 supports a concrete formwork (not shown) that is assembled in front of the existing part of the bridge girder 104a. By pouring concrete into this concrete formwork, a box girder block Pn for one block is constructed in front of the existing part of the bridge girder 104a. As shown in FIG. 4, corresponding to each of the two box girders 105 to be constructed, the formwork supporting portions 139 are two formworks for the box girder block Pn arranged and arranged in the direction orthogonal to the bridge axis. Support.

(Reinforcing bar tip assembly device)
The rebar tip assembly device 141 has a front work floor 147 suspended from the upper beam 137 and the horizontal member 134 via a plurality of suspension members 145. In the present embodiment, the front working floor 147 is suspended at each of the front ends of the three connecting beams 137c of the upper beam 137, and both ends and the central part of the horizontal member 134 in the direction perpendicular to the bridge axis, at a total of 6 positions. It is suspended and supported via a member 145. On the front work floor 147, the rebar cage 150 is assembled for use in the next box girder block P(n+1). On the front work floor 147, for example, a reinforcing bar ruler is installed as a guide for arranging the reinforcing bars at an equal pitch. As shown in FIG. 4, in the rebar preassembly device 141, two rebar cages 150 arranged in the direction perpendicular to the bridge axis are assembled corresponding to each of the two box girders 105 to be constructed.

(Trolley device)
As shown in FIG. 2, the rebar preassembly device 141 has a trolley device 151 (rebar cage transfer device). The trolley device 151 is a device for suspending and moving the rebar cage 150 assembled on the front work floor 147. The trolley device 151 is arranged below the extension beam 132. Further, a sufficient space for assembling and suspending the rebar cage 150 is secured between the trolley device 151 and the front work floor 147. The trolley device 151 includes a trolley rail 153 extending in the bridge axis direction, and a trolley 155 that is guided by the trolley rail 153 to move and that can suspend the reinforcing bar basket 150. By providing such a reinforcing bar tip assembly device 141, in parallel with the work of assembling the form of the box girder block Pn, concrete placing and curing, the assembling work of the rebar cage 150 for the box girder block P(n+1) can be performed. It becomes possible to perform operations such as performing.

(Widening follow-up mechanism)
As described above, each of the four main frames 131 needs to be always arranged on the web of the box girder 105. Since the box girder 105 of the present embodiment gradually widens as the overhanging construction method progresses, the spacing between the webs of the box girder 105 also gradually increases. Therefore, at least two main frames 131 at both ends of the four main frames 131 can be moved in parallel in the direction perpendicular to the bridge axis. Specifically, the movable main frame 131 and the horizontal members 137a and 137b are joined via a slide mechanism 157 (FIG. 3). Then, by the slide mechanism 157, the horizontal members 137a and 137b can be slid relative to the main frame 131 in the direction perpendicular to the bridge axis. With such a mechanism, the position of the main frame 131 in the direction perpendicular to the bridge axis can be made to follow even when the box girder 105 is widened as the erection and erection progresses. Here, it is assumed that the space between the two box girders 105, 105 does not change regardless of the widening of the box girder 105.

(Overhang construction method)
The procedure of the overhanging construction method executed by the mobile work vehicle 121 described above is as follows. As shown in FIG. 5A, the mobile work vehicle 121 is installed above the existing box girder block P(n-1) of the existing part of the bridge girder 104a, and the formwork support 139 is provided for the box girder block Pn. The formwork is assembled, and the concrete of the box girder block Pn is placed on the formwork and cured. A rebar cage for the box girder block Pn is installed in the formwork. In parallel with this work, in the reinforcing bar tip assembly device 141, the reinforcing bar basket 150 for the box girder block P(n+1) is assembled on the front work floor 147.

Thereafter, as shown in FIG. 5B, the box girder block Pn is completed, and the rail 123 is extended on the box girder block Pn. After that, the mobile work vehicle 121 is moved forward and installed above the box girder block Pn. Next, as shown in FIG. 5C, the trolley device 151 lifts the rebar cage 150 on the front work floor 147, and the trolley device 151 suspends the rebar cage 150 to move backward, The rebar cage 150 is installed in the formwork support 139 (scheduled construction position of the box girder block P(n+1)).

After that, as shown in FIG. 5(d), a mold is assembled so as to surround the rebar cage, and a rebar for the upper plate 105c (FIG. 3) is further installed in the mold, and a box is placed in the mold. The concrete of the girder block P(n+1) is poured and cured. In parallel with this work, in the reinforcing bar tip assembly device 141, the reinforcing bar basket 150 for the box girder block P(n+2) is assembled on the front work floor 147. By repeating the above procedure, the box girder block P is formed step by step.

Next, a suspension method and a suspension structure for suspending the rebar cage 150 previously assembled on the front work floor 147 by the trolley device 151 will be described in detail.

(Rebar cage)
As shown in FIG. 3, the box girder block P in which the rebar cage 150 is embedded includes a bottom slab 105a extending along a substantially horizontal plane, and a pair of slabs rising substantially vertically upward from both end edges of the bottom slab 105a and facing each other in the direction perpendicular to the bridge axis. The box girder block P has a hollow rectangular cross section, which is a reinforced concrete structure having substantially parallel webs 105b (side walls).

FIG. 6A is a cross-sectional view of the rebar cage 150, which has a cross section orthogonal to the bridge axis direction. As shown in FIG. 6A, the rebar cage 150 has a substantially U-shaped cross-sectional shape corresponding to the shape of the box girder block P as described above. That is, the reinforcing bar basket 150 includes the bottom plate reinforcing bar portion 11 embedded in the bottom plate 105a (FIG. 3) of the box girder block P and the pair of side wall reinforcing bars embedded in the pair of webs 105b (FIG. 3) of the box girder block P. And a part 13. Although the rebar of the rebar cage 150 preassembled is used for the bottom plate 105a and the web 105b of the box girder block P, the upper plate 105c (FIG. 3) of the box girder block P is made of concrete. The rebar is installed just before.

The bottom slab rebar portion 11 extends along a substantially horizontal plane, and the pair of side wall rebar portions 13 rises substantially vertically upward from both edges of the bottom slab rebar portion 11 in the direction perpendicular to the bridge axis and face each other in the direction perpendicular to the bridge axis. It is provided. The reinforcing bar basket 150 is formed in a basket shape by binding the reinforcing bars extending in the vertical and horizontal directions, which will be described below, with a binding line at the intersection.

The slab bottom reinforcing bars 11 are bottom slab upper bars 15 extending along the upper surface of the bottom slab reinforcing bars 11 in the direction perpendicular to the bridge axis, and bottom slab lower reinforcing bars extending along the bottom surface of the bottom slab reinforcing bars 11 in the direction perpendicular to the bridge axis. 17 and. A large number of bottom slabs 15 and bottom slabs 17 are arranged in parallel in a direction (bridge axis direction) orthogonal to the paper surface of FIG. Further, the bottom slab rebar portion 11 has a plurality of bridge axial rebars 16 that extend in the bridge axis direction directly below the bottom slab upper reinforcement 15 and are bound to each bottom slab upper reinforcement 15 at each intersection. Further, the bottom slab rebar portion 11 has a plurality of bridge axial direction rebars 18 extending in the bridge axis direction directly above the bottom slab bottom bars 17 and bound to the bottom slab bottom bars 17 at each intersection. Both ends of the bottom slab 17 are bent upward along the shape of the lower end of the web reinforcing bar 19 described later.

The side wall reinforcing bar portion 13 includes a web reinforcing bar 19 formed in a U shape in a substantially vertical plane so as to extend along the inner side surface and the outer side surface of the web 105b (FIG. 3). A large number of web reinforcing bars 19 are arranged in parallel to the direction (bridge axis direction) orthogonal to the paper surface of FIG. The web reinforcing bar 19 is embedded along the outer wall surface of the web 105b (FIG. 3) and extends in the substantially vertical direction, and the web rebar 19 is embedded along the inner wall surface of the web 105b (FIG. 3) and in the substantially vertical direction. The inner portion 19b extending to the lower end is connected at the lower end to have a substantially U shape. The upper ends of the web reinforcing bars 19 are respectively bent in the direction perpendicular to the bridge axis toward the outside of the web 105b. The bent portion of the web reinforcing bar 19 is called a bent portion 19c. Further, the side wall reinforcing bar portion 13 has a plurality of bridge axial direction reinforcing bars 20 extending in the bridge axis direction immediately inside the outer side portion 19a of the web reinforcing bar 19 and bound to the outer side portion 19a at each intersection. Further, the side wall reinforcing bar portion 13 has a plurality of bridge axial direction reinforcing bars 22 which extend in the bridge axis direction immediately inside the inside portion 19b of the web reinforcing bar 19 and which are bound to the inside portion 19b at each intersection.

(Reinforcement basket suspension method and suspension structure)
In the reinforcing bar tip assembly device 141 (FIG. 2), when the reinforcing bar basket 150 assembled as described above is suspended by the trolley device 151, the reinforcing bar basket 150 is bent due to its own weight. When the bending of the reinforcing bar basket 150 is large, irreversible deformation is likely to occur particularly in the binding portion between the reinforcing bars, and as a result, the deformation of the entire reinforcing bar basket 150 may remain. Further, the above-mentioned binding portion may be damaged and the binding work may have to be redone. As a measure against this problem, a suspending method and a suspending structure of the rebar cage 150 according to the present embodiment will be described.

FIG. 6B is a cross-sectional view showing a state in which each jig for hanging is attached to the reinforcing bar basket 150 of FIG. 6A. 7: is a figure which expands and shows a part of bottom slab rebar part 11, FIG.7(a) is sectional drawing which took the cross section parallel to a bridge axis right angle direction, FIG.7(b) is a bridge axis. It is sectional drawing which took the cross section parallel to a direction. Further, FIG. 8 is an enlarged cross-sectional view showing a portion where the bottom plate reinforcing bar portion 11 and the side wall reinforcing bar portion 13 in FIG. 6B intersect. Although FIG. 8 illustrates only one of the portions where the bottom plate reinforcing bar portion 11 and the side wall reinforcing bar portion 13 intersect with each other, the other part of the portion also has the same configuration, and thus duplicated illustration is omitted. To do. Further, FIG. 9 is an enlarged cross-sectional view showing the vicinity of the upper end of the side wall reinforcing bar portion 13 in FIG. 6B.

(First suspended beam member)
First, as shown in FIG. 6B and FIG. 7, a plurality of first suspension beam members 21 extending in the bridge axis direction are installed below the bottom slab 17 of the reinforcing bar basket 150. The first suspension beam member 21 has a bending rigidity higher than that of the bottom plate lower reinforcement 17 and the bridge axial direction reinforcement 18, and is, for example, a round steel material. In the example shown in FIG. 6B, seven first suspension beam members 21 are arranged below the bottom slab reinforcement 11. Although the length of the first suspension beam member 21 is not particularly limited, it is preferably a length that traverses under the plurality of bottom plate inversion lines 17. Furthermore, it is preferable that the first suspension beam member 21 traverses under all the bottom slabs 17. Therefore, the length of the first suspension beam member 21 is almost the entire length of the reinforcing bar basket 150 in the bridge axis direction. It is preferable that the length is across.

(Second suspended beam member)
Subsequently, the second suspension beam member 23 extending in the direction perpendicular to the bridge axis is installed above the bottom slab 17 and the bridge axis direction reinforcing bar 18. The second suspension beam member 23 is inserted into the gap between the bridge axial direction reinforcing bar 18 and the bridge axial direction reinforcing bar 16. The one second suspension beam member 23 is composed of two channel members 23a symmetrically arranged with their outer web surfaces facing each other. As a whole, the bottom plate rebar 17 and the bridge axial direction rebar 18 Also has a high bending rigidity. The second suspension beam member 23 is connected to the first suspension beam member 21 with the bottom plate lower reinforcement 17 and the bridge axial direction reinforcing bar 18 interposed therebetween. Specifically, both ends of the U-shaped bolt 27 hooked on the first suspension beam member 21 are inserted into the baskets of the bottom plate lower reinforcement 17 and the bridge axial direction reinforcement 18. Then, both ends of the U-shaped bolt 27 projecting upward from the basket pass through the gap between the two channel members 23a and are hooked on the upper surface of the second suspension beam member 23 by the nut 29 and the hook plate 31. Thus, the first suspension beam member 21 is fastened to the second suspension beam member 23. The fastening portion as described above is formed at each intersection of the first suspension beam member 21 and the second suspension beam member 23.

In the bottom plate rebar portion 11 of the present embodiment, the three second suspension beam members 23 having the above-described configuration are arranged at a predetermined interval in the direction (bridge axis direction) orthogonal to the paper surface of FIG. 6B. To be done. The second suspension beam member 23 exists over almost the entire length of the reinforcing rod basket 150 in the direction perpendicular to the bridge axis, and as shown in FIG. 8, both ends of the second suspension beam member 23 are It is located at a portion where the bottom plate reinforcing bar portion 11 and the side wall reinforcing bar portion 13 intersect.

(Suspension tension material)
Subsequently, as shown in FIGS. 6B and 8, one suspension tension member 35 is connected to each end of each second suspension beam member 23. The suspension tension member 35 extends in a substantially vertical direction between the bridge axial direction reinforcing bar 20 and the bridge axial direction reinforcing bar 22 in the central portion of the side wall reinforcing bar portion 13 in the thickness direction of the web 105b. The lower end of the suspension tension member 35 is inserted into the gap between the two channel members 23a at the end portion of the second suspension beam member 23 in the direction perpendicular to the bridge axis, and the nut 29 and the latch plate 31 are used to form the second suspension beam member. It is hooked on the lower surface of the material 23. The upper end of the suspension tension member 35 is connected to a suspending device 37 described later. The pair of suspension tension members 35 connected to both ends of the one second suspension beam member 23 suspends and supports the one second suspension beam member 23 with both ends. In the rebar cage 150, a total of 6 suspension tension members 35 are installed, and the three second suspension beam members 23 are suspended from both ends and supported.

(Single pipe)
Further, as shown in FIGS. 6B and 9, a pair of upper and lower single-pipe pipes 39 extending in the bridge axis direction and vertically sandwiching the bent portions 19c are installed for the respective bent portions 19c. .. As shown in FIG. 10, holes 39a are formed in the pipe wall of the single pipe 39 at the same arrangement pitch as the web reinforcing bars 19. The holes 39a are shallowly fitted into the side circumferential surfaces of the bent portions 19c of the web reinforcing bars 19, whereby irregular movement of the bent portions 19c in the bridge axis direction is suppressed and the arrangement pitch of the upper end of the web reinforcing bars 19 is reduced. Disturbance is suppressed. Further, each web reinforcing bar 19 is stably clamped at the upper end. The pair of upper and lower single-pipe pipes 39 are connected to a suspending device 37 described later via a U-shaped thin iron plate 41 and slicing bolts 42 provided at both ends of the thin iron plate 41.

(Hanging device)
Subsequently, as shown in FIGS. 6B and 9, with respect to the suspending device 37 disposed above each side wall reinforcing bar portion 13, the upper end of the suspension tension member 35 and the single pipe pipe 39 are provided. , Are fixed. The suspension device 37 has a cross beam structure by a plurality of horizontal beam members 43 extending in the direction perpendicular to the bridge axis and a plurality of vertical beam members 45 joined to the upper surface of the horizontal beam member 43 and extending in the bridge axis direction. Is formed. One horizontal beam member 43 is composed of two square pipes 43a arranged in parallel (see FIG. 11). One vertical beam member 45 is composed of two channel members 45a that are symmetrically arranged with their web outer surfaces facing each other. In the present embodiment, the suspending device 37 is composed of three horizontal beam members 43 and three vertical beam members 45.

A bolt 47 is inserted substantially vertically into the gap between the square pipes 43a of the horizontal beam member 43 and the gap between the channel members 45a of the vertical beam member 45, and the nut 29 and the latch plate 31 are attached to the upper and lower ends thereof, respectively. The horizontal beam member 43 and the vertical beam member 45 are firmly fastened by being tightened. The upper end of the suspension tension member 35 is connected to the suspending device 37 so as to be hooked on the upper surface of the lateral beam member 43 by the nut 29 and the hook plate 31. In addition, the pair of upper and lower single pipes 39 includes a U-shaped thin iron plate 41 and slicing bolts 42 provided at both ends of the thin iron plate 41, and a nut 29 and a locking plate 31 to provide an upper surface of the horizontal beam member 43. It is connected to the suspending device 37 so that it is hooked on.

(Sliding mechanism of sling part)
Further, among the plurality of vertical beam members 45, the vertical beam member 45 positioned directly above the suspension tension member 35 is provided with two device suspension receiving members 51 arranged at predetermined intervals in the bridge axis direction. ing. The device suspension member 51 has, for example, H steel shorter than the channel material 45a, and the web of the H steel is located between the channel materials 45a. Further, the upper and lower flanges of the H steel are hooked on the upper surface and the lower surface of the vertical beam member 45, respectively, so that the vertical movement of the device suspension member 51 with respect to the vertical beam member 45 is restricted. Further, the apparatus steel support member 51 is slidable with respect to the longitudinal beam member 45 in the bridge axis direction at a predetermined stroke by sliding the H steel flange and the web relative to the channel member 45a. Further, the device suspension support member 51 has a sling portion 51a provided on the upper surface of the H steel flange.

FIG. 11 is a view of a state in which the reinforcing bar cage 150 is suspended by the trolley 155 (suspension means), as viewed from the direction perpendicular to the bridge axis. Note that, in FIG. 11, a large number of reinforcing bars constituting the reinforcing bar cage 150 are omitted and only the outline of the reinforcing bar cage 150 is shown as a quadrangle. As shown in FIG. 11, a swivel hook 55 is hooked on each sling portion 51 a, and the swivel hook 55 is connected to the trolley 155 via an electric chain block 57. The rebar cage 150 assembled on the front work floor 147 (FIG. 2) is lifted upward by the electric chain block 57 at the above-mentioned four slings 51a, and hung by the trolley 155 through the electric chain block 57. To be Then, the trolley 155 is guided by the trolley rail 153 and moves in the bridge axis direction, so that the reinforcing bar basket 150 moves in the bridge axis direction.

Next, the configuration in which the device suspension receiving member 51 (sliding member) of the suspending device 37 is displaced relative to the reinforcing bar basket 150 along the side wall reinforcing bar portion 13 in a plan view will be described in more detail. As shown in FIG. 9, the suspending device 37 has three vertical beam members 45 extending in parallel to the side wall reinforcing bar portion 13. Of these three vertical beam members 45, A device suspension member 51 is provided.

FIG. 12 is an exploded perspective view showing the central vertical beam member 45 provided with the device suspension supporting member 51. As shown in FIG. 12, the vertical beam member 45 has two channel members 45a and 45a which are symmetrically arranged with their outer web surfaces 46 and 46 facing each other in the horizontal direction. The device suspension member 51 includes H steel 53, and the H steel 53 has upper and lower flanges 53a and webs 53b. Further, the device suspension support member 51 includes a sling portion 51a provided on the upper surface of the flange 53a of the H steel 53. The web 53b of the H steel 53 is sandwiched between the channel members 45a, 45a.

The vertical length of the web 53b of the H steel 53 is longer than the vertical length of the outer web surface 46 of the channel member 45a. Therefore, the upper flange 53a of the H steel 53 is hooked on the upper surface 45h of the vertical beam member 45, and the lower flange 53a of the H steel 53 is hooked on the lower surface 45j of the vertical beam member 45. With such H steel 53, the vertical movement of the device suspension member 51 with respect to the vertical beam member 45 is restricted. Accordingly, the hanging device 37 and the reinforcing bar basket 150 can be hung by being slung on the slinging portion 51a of the device suspension receiving member 51. Further, the H steel 53 slides in the bridge axis direction with respect to the channel member 45 a, whereby the device suspension member 51 can move in the bridge axis direction with respect to the vertical beam member 45. As a result, the device suspension receiving member 51 can be displaced along the side wall reinforcing bar portion 13 of the reinforcing bar cage 150 connected to the vertical beam member 45. Further, as shown in FIG. 11, the sling portion 51a of the device suspension member 51 is connected to the trolley 155 via the swivel hook 55 having a swivel mechanism, so that the vertical axis of the device suspension member 51 with respect to the trolley 155 is vertical. Rotation around is also allowed.

Next, the function and effect of the device suspension supporting member 51 having the above configuration will be described with reference to FIG.

Here, as described above, the mobile work vehicle 121 can handle the two rebar cages 150 (see FIG. 4) arranged in the direction perpendicular to the bridge axis. Since the configurations for handling these two reinforcing bar cages 150 are the same as each other, only the suspension transfer of one of the reinforcing bar cages 150 will be described below. Therefore, the following description relates to two main frames 131 installed on the pair of webs 105b of one box girder 105, as shown in FIGS. 13(a) and 13(b). FIGS. 13A and 13B are plan views schematically showing the positional relationship between the two main frames 131, the reinforcing bar cage 150, the bridge girder existing portion 104a, and the like. FIG. 13 is a plan view showing a state in which the box girder 105 under construction widens as it goes forward, but the widening of the box girder is exaggeratedly depicted. Further, in FIG. 13, only constituent elements of the mobile work vehicle 121 necessary for description are depicted, and other constituent elements such as the upper beam 137 are not shown.

As shown in FIGS. 13A and 13B, the trolley device 151 moves while being guided by the pair of trolley rails 153 extending along the extension line of the web 105b in plan view. And a trolley 155. The trolley rails 153 are provided for the main frames 131, respectively, and extend in the same direction at positions overlapping the main frames 131 in a plan view.

First, as shown in FIG. 13( a ), when the box girder 105 under construction widens as it goes forward, the rebar cage 150 for the box girder block Pn moves from the rebar tip assembly device 141 to the formwork behind it. Consider the case where it is relocated to the support portion 139. In this case, the rail 123 of the mobile work vehicle 121 is laid so as to open in a V shape as it goes forward in a plan view. The pair of main frames 131 moving on the rails 123 are also arranged in a V shape in a plan view, and the pair of trolley rails 153 provided in each main frame 131 are also arranged in a C shape. That is, the width between the trolley rails 153 (width in the direction perpendicular to the bridge axis) increases as it goes forward.

Therefore, at the position corresponding to the rebar tip assembly device 141, the width between the trolley rails 153 is larger than the width between the trolley rails 153 in the frame support 139. On the other hand, the width of the reinforcing bar basket 150 for the box girder block Pn assembled by the reinforcing bar tip assembly device 141 corresponds to the width of the form support 139. Therefore, in the rebar preassembly device 141, the width between the trolley rails 153 is larger than that of the rebar cage 150 to be assembled.

Then, as shown in FIG. 13A, the device suspension member 51 is not arranged at a position vertically below the trolley 155, but is positioned slightly inside the trolley 155. Then, when the rebar cage 150 is hoisted from the rebar tip assembly device 141, the trolley 155 and the sling portion 51a are obliquely connected by the chain of the electric chain block 57 (FIG. 11), and the device suspension receiving member 51 of the rebar basket 150 is connected. Will be pulled diagonally upward toward the outside. As a result, a force is applied to expand the upper end portion of the reinforcing bar basket 150 in the direction perpendicular to the bridge axis, which causes deformation of the reinforcing bar basket 150. The same problem occurs when the box girder 105 under construction narrows as it goes forward.

As a countermeasure against this, as described above, the device suspension receiving member 51 is relatively displaceable with respect to the reinforcing bar basket 150 and is displaced along the side wall reinforcing bar portion 13 in a plan view. According to this configuration, when the device suspension receiving member 51 is pulled outward in the direction perpendicular to the bridge axis when the reinforcing bar basket 150 is suspended, as shown in FIG. Moves to the outside, and accordingly, the rebar cage 150 retracts relative to the apparatus suspension member 51 in the direction toward the mold support 139. As a result, the device suspension receiving member 51 approaches the position vertically below the trolley 155, and the force for expanding the reinforcing bar basket 150 in the direction perpendicular to the bridge axis is reduced.

That is, the device suspension member 51 slides along the side wall reinforcing bar portion 13 to automatically shift to the arrangement for reducing the force. As a result, the mismatch between the width between the trolley rails 153 and the width of the reinforcing bar basket 150 at the position of the reinforcing bar tip assembly device 141 is absorbed to some extent, and the deformation of the reinforcing bar basket 150 due to the mismatch can be suppressed. Further, since the swivel hook 55 allows relative horizontal rotation of the trolley 155 and the device suspension member 51, the horizontal rotation of the device suspension member 51 causes the width between the trolley rails 153 and the width of the reinforcing bar basket 150 to be different. The deformation of the rebar cage 150 due to the disagreement is suppressed.

As described above, in the case where the box girder 105 whose width changes toward the front is being constructed, the deformation of the reinforcing bar cage 150 due to the mismatch between the width between the trolley rails 153 and the width of the reinforcing bar cage 150 is suppressed. It

Further, the vertical beam member 45 of the suspending device 37 has two channel members 45a, and the device suspending/receiving member 51 has H steel 53 sandwiched between the channel members 45a. In this way, the slide mechanism of the device suspension member 51 can be configured by general-purpose elements such as the channel material and H steel.

Further, the suspending device 37 guides the device suspending member 51 by the central vertical beam member 45 (guide beam member), and two other vertical beam members 45 (auxiliary beam members) sandwiching the vertical beam member 45. Is equipped with. Then, these three vertical beam members 45 and the three horizontal beam members 43 substantially orthogonal to the vertical beam members 45 are rigid using bolts 47, nuts 29, locking plates 31 (FIG. 9) and the like. It has a double-digited structure. With such a structure, even when an irregular force that pulls the device suspension receiving member 51 obliquely upward as described above acts, the deformation of the hanging device 37 (in particular, the deformation in the horizontal plane) is suppressed, The rebar cage 150 can be stably hung.

Further, the operation method and effect of the suspending method and the suspending structure of the reinforcing bar basket 150 described above will be described. In the above-described suspension method and suspension structure, the first suspension beam member 21 and the second suspension beam member 23, which have higher bending rigidity than the bottom slab 17 and the like, are provided along the lower surface of the bottom slab reinforcement 11. The bottom suspension bars 17 and the bridge axial direction reinforcement bars 18 are vertically sandwiched between the first suspension beam members 21 and the second suspension beam members 23. Then, each of the second suspension beam members 23 is hung and supported by both ends, and the hung and supported position is the central portion of the side wall reinforcing bar portion 13 in the wall thickness direction. With such a structure, since the bottom slab rebar portion 11 is hung while being supported by the first suspension beam member 21 and the second suspension beam member 23 having high bending rigidity, the flexure of the bottom slab member 11 is suppressed. .. Further, since the bending of the bottom plate reinforcing bar portion 11 is suppressed, the vertical posture of the side wall reinforcing bar portion 13 is maintained, and the bending of the side wall reinforcing bar portion 13 can also be suppressed.

The second suspension beam member 23 is composed of two channel members 23 a symmetrically arranged with their outer web surfaces facing each other, and the first suspension beam member 21 is a gap between the bottom plate lower bars 17. And is fastened to the second suspension beam member 23 by U-shaped bolts 27 that pass through the gap between the two channel members 23a and are vertically inserted. As described above, the first suspension beam member 21, the second suspension beam member 23, and the like can be configured by general-purpose elements such as the channel member 23a and the U-shaped bolt 27.

The suspending device 37 has a cross beam structure including a plurality of vertical beam members 45 extending in the bridge axis direction and a horizontal beam member 43 extending in a direction orthogonal to the vertical beam members 45. According to this configuration, the deformation of the suspending device 37 itself (in particular, the deformation in the horizontal plane) is suppressed, and the posture of the reinforcing bar basket 150 during the suspension is stabilized.

Further, as another method for suppressing the bending of the reinforcing bar basket 150, it may be considered that a large number of slings are evenly arranged in the reinforcing bar basket 150 in a plan view. However, in this type of mobile work vehicle 121, various structures and devices are often arranged in the space above the rebar cage 150, and a large number of hanging materials can be freely arranged in the space above the rebar cage 150. Often difficult to move. On the other hand, in this type of mobile work vehicle 121, there are relatively few structures and devices arranged in the space vertically above the web 105b of the box girder 105. Therefore, as in the suspending method and the suspending structure of the present embodiment, it is preferable that the sled portions 51a of the reinforcing bar basket 150 are provided concentrated on the side wall reinforcing bar portions 13.

The present invention can be implemented in various modes including various modifications and improvements based on the knowledge of those skilled in the art, including the above-described embodiment. In addition, it is possible to configure a modified example of the example by utilizing the technical matters described in the above-described embodiment. The configurations of the respective embodiments may be appropriately combined and used.

For example, in the embodiment, as a mechanism for displacing the device suspension member 51, a mechanism in which the channel materials 45a, 45a and the H steel 53 are combined is adopted, but the mechanism is not limited to this and various mechanisms are adopted. can do.

11... Bottom plate reinforcing bar portion, 13... Side wall reinforcing bar portion, 37... Hanging device, 43... Horizontal beam member, 45... Vertical beam member, 45h... Top surface, 45j... Bottom surface, 45a... Channel material, 46... Web outer surface, 51... Device Suspension receiving member (sliding member), 55... Swivel hook (swivel mechanism, suspension material), 57... Electric chain block (suspension material), 53... H steel, 53a... Flange, 53b... Web, 100... Bridge, 105a... Bottom plate , 105b... Web (side wall), 121... Mobile work vehicle, 131... Main frame, 139... Formwork support (construction planned position), 150... Reinforcing bar cage, 151... Trolley device (rebar cage moving device), 153... Trolley Rails, 155... Trolley, P... Box girder block.

Claims (4)

A rebar cage moving device for moving a rebar cage embedded in a box girder block constructed by a bridge overhanging method to a construction planned position of the box girder block by suspending it with a mobile work vehicle,
The box girder block has a bottom plate, and a pair of opposing side walls provided so as to rise from both end edges of the bottom plate,
The mobile work vehicle has a pair of main frames arranged along each of the pair of side walls of the existing box girder block in a plan view,
The rebar cage has a bottom plate rebar portion embedded in the bottom plate, and a pair of opposing side wall rebar portions embedded in the side wall,
A pair of trolley rails provided on each of the main frames and extending along an extension line of the side wall in a plan view,
A trolley that is guided and moved by the trolley rail,
Arranged above each of the pair of side wall rebar portions of the rebar cage, a pair of suspending devices that are connected to each of the side wall rebar portions and are hung and supported from the trolley via suspension members,
The suspending device includes a slinging member to which the suspending member is connected, and the slinging member is displaceable relative to the reinforcing bar cage along the side wall reinforcing bar portion in a plan view. apparatus. The rebar cage transfer device according to claim 1, wherein the suspension member has a swivel mechanism that allows relative rotation of the trolley and the sling member around a vertical axis. The hanging device,
A vertical beam member including two channel members arranged symmetrically with their outer web surfaces facing each other and extending along the side wall reinforcing bar portion in a plan view;
The sling member is
H steel having a web sandwiched between the channel members and upper and lower flanges hooked on the upper surface and the lower surface of the vertical beam member is provided. The rebar cage moving device according to claim 1 or 2, wherein the rebar cage moving device can be displaced along the side wall rebar portion by sliding. The hanging device,
A guide beam member that guides the sling member, an auxiliary beam member that extends in parallel to the guide beam member, a guide beam member and a guide beam member that extends in a direction substantially orthogonal to the auxiliary beam member, and The rebar cage transfer device according to any one of claims 1 to 3, having a cross beam structure having a horizontal beam member rigidly connected to the auxiliary beam member.

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