JP7620525B2 - Bridge construction method and slide jig - Google Patents

Description

The present invention relates to a bridge construction method and a sliding jig used therein.

Patent Document 1 describes a method for constructing a cable-stayed bridge in which girder blocks are connected from each of the adjacent piers toward the span, and the girder blocks connected from each pier are closed at the closure of the span.

Patent Publication No. 2007-262796

In the method of Patent Document 1, the girder is extended from the pier to the closure of the span by connecting girder blocks from the pier toward the closure of the span, but when the final block is installed, there is no room in the gaps between the girders extended from each pier, making it difficult to place the final block.

For this reason, it is possible to set back the bridge girders before installing the final block, leaving some space between the girders, and then place the final block. It is also known that during bridge construction, horizontal force is applied in advance to the rubber bearings supporting the bridge girders using jacks or other tools in order to mitigate the effects of shrinkage deformation of the bridge girders due to creep and drying, and the same method can be used to set back the bridge girders.

In this case, however, a force application tool such as a jack must be attached to the support, which requires machining of the support, increasing the amount of work required and the cost. There is also a risk of damage to the support when force is applied.

The present invention was made in consideration of the above problems, and aims to provide a bridge construction method that allows bridge girders to be easily closed together.

A first invention for solving the above-mentioned problems is a bridge construction method in which bridge girders are closed together with a closing unit arranged at a closing section, the method comprising the steps of: moving one of the bridge girders back to widen the gap at the closing section; placing a closing unit at the closing section; and moving one of the bridge girders forward to return the gap at the closing section to its original state and closing the bridge girders with the closing unit. When one of the bridge girders moves back and forward, a reaction force is supported on the pier by a reaction part of a sliding jig, and a horizontal force is applied directly to one of the bridge girders by a force application part of the sliding jig, causing one of the bridge girders to slide relative to the pier. The sliding jig has the reaction part and the force application part provided on a beam arranged in the bridge axis direction, and a rail is provided on the top surface of the pier for moving the beam in a direction perpendicular to the bridge axis .
A second invention is a bridge construction method for constructing a bridge by closing bridge girders together with a closing unit arranged at a closing section, the method comprising the steps of: retracting one of the bridge girders to widen the gap at the closing section; arranging a closing unit at the closing section; and advancing the one of the bridge girders to return the gap at the closing section to its original state and closing the bridge girders together with the closing unit. When the one of the bridge girders is retracted and advanced, a reaction force is supported on the pier by a reaction part of a sliding jig, and a horizontal force is directly applied to the one of the bridge girders by a force application part of the sliding jig, thereby sliding the one of the bridge girders relative to the pier, This is a bridge construction method, characterized in that the force application unit applies a horizontal force to a protrusion on a side of one of the bridge girders, and the sliding jig is arranged to straddle the pier, a beam protruding from the front and rear of the pier, a first support unit provided on the underside of the beam so as to sandwich the pier from the front and rear, the reaction unit attached to the first support unit and abutting the front and rear surfaces of the pier, a second support unit provided on the upper surface of the beam so as to sandwich the protrusion from the front and rear, and a jack as the force application unit attached to the second support unit and applying a horizontal force to the protrusion.

In the present invention, when constructing a bridge such as a cable-stayed bridge by closing bridge girders with a closing unit, the closing unit can be easily placed in the closing part by widening the gap between the closing parts in advance to allow some leeway, and then both bridge girders can be closed with the closing unit by narrowing the gap between the closing parts. In this case, the above-mentioned sliding jig is used to apply a horizontal force directly to the bridge girders to slide them, eliminating the need to process the supports and preventing damage to the supports. In addition, the reaction force during sliding is supported by the bridge piers, so that the reaction force can be handled simply by appropriately reinforcing the piers with reinforcing bars, etc.

Furthermore, in the second invention , the slide jig can be installed on the side portion of the bridge girder, which has a relatively large space with few restrictions, making construction easier.

Furthermore, the slide jig of the second invention has a relatively simple structure and can be formed using readily available general-purpose items such as H-beams and hydraulic jacks, and does not require special or dedicated parts.

It is desirable that the one bridge girder is provided on a bearing on the top surface of the pier, the bearing being a rubber bearing that deforms in association with the retreat of the one bridge girder.
In this invention, since horizontal force is applied directly to the bridge girder, the rubber bearings supporting the bridge girder deform as the bridge girder retreats. The deformation caused by the bridge girder retreat is within the range that is normally permissible for seismic isolation rubber bearings, and no damage will occur.

The third invention is a sliding jig for sliding a bridge girder relative to a pier when constructing a bridge by closing bridge girders together with a closing unit placed at the closing part, the sliding jig having a reaction force part for supporting a reaction force on the pier, a force application part for applying a horizontal force directly to the bridge girder, and a rail provided on the top surface of the pier , wherein the sliding jig is characterized in that the reaction force part and the force application part are provided on a beam material that is arranged in the bridge axis direction, and the rail is for moving the beam material in a direction perpendicular to the bridge axis .
The fourth invention is a sliding jig for sliding a bridge girder relative to a pier when constructing a bridge by closing girders together with a closing unit arranged at a closing part, the sliding jig comprising: a beam arranged to straddle the pier and protruding from the front and rear of the pier; a first support part provided on the underside of the beam so as to sandwich the pier from the front and rear; a reaction part attached to the first support part and abutting the front and rear sides of the pier for supporting a reaction force on the pier; a second support part provided on the upper surface of the beam so as to sandwich a protrusion on the side of the bridge girder from the front and rear; and a jack attached to the second support part as a force application part that applies a horizontal force directly to the protrusion .

The present invention provides a bridge construction method that allows bridge girders to be easily closed together.

A diagram showing the bridge. A diagram showing how a bridge is constructed. FIG. 13A and 13B are diagrams explaining the retreat and advancement of the bridge girder 2 by the slide jig 10. FIG. FIG.

The following describes in detail a preferred embodiment of the present invention with reference to the drawings.

(1. Bridge Construction Method)
FIG. 1 is a diagram showing a bridge in the middle of construction, which is constructed by a construction method according to an embodiment of the present invention.

This bridge is a cable-stayed bridge, with girders 2 installed on piers 1 and suspended from towers 3 by diagonal members 4 such as cables.

The side span side (bridge end side) of the bridge girder 2 is a concrete girder 2a formed from concrete, and the center span side (bridge center side) of the bridge girder 2 is a steel girder 2b formed from steel.

A sliding jig 10 for sliding the bridge girder 2 is provided on the pier 1 located on the central span side. The sliding jig 10 is used when closing the closure section C between the tip of the bridge girder 2 on the central span side and the tip of the adjacent bridge girder 2' on the central span side. Hereinafter, the tips of the bridge girders 2, 2' on the central span side may be simply referred to as the "tips".

The girder 2' is also placed on a pier (not shown) and is supported by being suspended from the tower by diagonal members. The configuration of the girder 2', pier, tower, and diagonal members is the same as that of the girder 2, pier 1, tower 3, and diagonal members 4 in Figure 1. Also, reference numeral 5 in the figure denotes a lifting device for hoisting the closing unit (described later) when the girders 2 and 2' are closed.

In this embodiment, after each bridge girder 2, 2' is constructed from the side span to the center span as shown in Figure 1, when closing the closing section C, one bridge girder 2 is set back (set back) to the side span side using a slide jig 10 as shown by arrow a in Figure 2(a). The setback width is not very large, about 100 mm.

This widens the gap at the closing section C, and the closing unit 6 is then lifted by the lifting device 5, which has been moved to the tip of the bridge girder 2 as shown in Figure 2(b), and placed at the closing section C as shown in Figure 2(c), and attached to the tip of the bridge girder 2.

The closing unit 6 is a steel girder formed from steel material. The length of the closing unit 6 is approximately the same as the spacing of the original closing parts C, and by setting back the bridge girder 2 in advance to widen the spacing of the closing parts C, sufficient space is ensured when placing (hoisting) the closing unit 6.

After the closing unit 6 is installed, the bridge girder 2 is advanced (set for) toward the closing section C by the slide jig 10, as shown by arrow b in Figure 2 (d), and the spacing of the closing section C is returned to its original position. The closing unit 6 is then connected to the other bridge girder 2', and the bridge girders 2, 2' are closed together by the closing unit 6. As for the bridge girder 2', it is also possible to move it back and forth by the slide jig 10 before and after the closing unit 6 is placed, as described above.

(2. Slide jig 10)
3 is a diagram showing a slide jig 10 for moving the bridge girder 2 back and forward. In the following description, the movement back and forward of the bridge girder 2 may be collectively referred to as "sliding the bridge girder 2."

Figure 3(a) is a view of the slide jig 10 from a direction perpendicular to the bridge axis, Figure 3(b) is a view of the slide jig 10 from the bridge axis direction, and Figure 3(c) is a view of the slide jig 10 from above. The direction perpendicular to the bridge axis corresponds to the direction normal to the paper surface in Figure 3(a), the left-right direction in Figure 3(b), and the up-down direction in Figure 3(c), while the bridge axis direction corresponds to the left-right direction in Figures 3(a) and (c), and the direction normal to the paper surface in Figure 3(b).

As shown in FIG. 3(b), the bridge girder 2 is placed on the supports 7 arranged on the top surface of the pier 1. The supports 7 are arranged on both sides perpendicular to the bridge axis. Rubber bearings are used as the supports 7, but are not limited to this.

The bridge girder 2 has protrusions 21 on both sides that protrude outward in the direction perpendicular to the bridge axis. As shown in FIG. 3(a), the protrusions 21 are provided on the bridge girder 2 at positions in the bridge axis direction that correspond to the bridge pier 1. The protrusions 21 are provided to allow the bridge girder 2 to slide using the slide jig 10.

The slide jig 10 has a stand 11, jacks 12 and 13, rails 14, etc. A pair of slide jigs 10 are provided on both sides of the bridge girder 2, and each slide jig 10 is disposed on a side portion of the bridge girder 2.

The stand 11 supports the jacks 12 and 13, and has support parts 112 and 113 at both ends of a beam 111. The beam 111 and support parts 112 and 113 are made of steel such as H-shaped steel or T-shaped steel.

The beam 111 is arranged in the bridge axis direction so as to straddle the pier 1, with both ends protruding in front of and behind the pier 1. The beam 111 is arranged on top of a rail 14 that is provided on the top surface of the pier 1 in a direction perpendicular to the bridge axis. Multiple rails 14 are arranged in parallel with gaps between them.

The frame 11 can be lowered between the bridge girder 2 and the main tower 3 as shown by arrow A in Figure 3(b), moved inward along the rails 14 in a direction perpendicular to the bridge axis, and set on the side of the bridge girder 2. Reference numeral 114 in Figure 3(a) denotes a hanging jig for hanging the frame 11, which is provided on the top surface of the beam 111 at both ends of the beam 111.

A pair of support parts 112 (first support parts) are provided on the underside of the beam 111 so as to sandwich the pier 1 from the front and rear. Jacks 12 are provided on the surface of each support part 112 facing the pier 1. The ends of these jacks 12 facing the pier 1 abut the front and rear surfaces of the pier 1, and function as reaction parts that allow the pier 1 to support the reaction force when the bridge girder 2 slides.

A pair of support parts 113 (second support parts) are provided on the upper surface of the beam material 111 so as to sandwich the protrusion part 21 of the bridge girder 2 from the front and rear. A jack 13 is provided on the surface of one of the support parts 113 facing the protrusion part 21. The jack 13 functions as a force application part that applies a horizontal force directly to the bridge girder 2 by pressing the protrusion part 21 with its extension.

In the example of Figure 3, the jack 13 is provided on the support part 113 on the central span side (corresponding to the right side of Figures 3(a) and (c)). When the bridge girder 2 shown in Figure 2(a) is to be retracted, the jack 13 is extended to push the protrusion 21 backward, thereby retracting the bridge girder 2 as shown by the arrow a in Figure 4(a).

On the other hand, when the bridge girder 2 advances as shown in FIG. 2(d), the jack 13 is moved to the support part 113 on the side span side (corresponding to the left side of FIG. 4(b)) as shown in FIG. 4(b), and the jack 13 is extended, so that the protrusion 21 is pushed forward and the bridge girder 2 can be advanced as shown by the arrow b.

The bridge girder 2 is supported by bearings 7 on the top surfaces of the piers 1, but in this embodiment, no horizontal force is applied to the bearings 7. As shown in FIG. 5(a), the rubber part 71 of the bearing 7 deforms (shears) from its original shape shown by the dotted line to the solid line as the bridge girder 2 retreats. When the bridge girder 2 is then advanced forward, the rubber part 71 returns to its original shape.

Note that supports are also provided on piers 1 other than the pier 1 on which the sliding jig 10 is installed, but these supports may slide in conjunction with the sliding of the bridge girder 2, or may be deformed in the same manner as described above.

In the former case, as shown in FIG. 5(b), for example, an anchor bolt 103, which is an anchor for fixing a base plate 102 for installing a bearing to the pier 1, is inserted into a hole 101 in the pier 1 that has a larger diameter than the anchor bolt 103, and the base plate 102 to which the bearing 7a is fixed can be slid relative to the pier 1. The hole 101 in the pier 1 is filled with a solidifying material or the like after the bridge girder 2 has advanced.

As described above, in this embodiment, when constructing a bridge by closing the bridge girders 2, 2' together with the closing unit 6, the closing unit 6 can be easily positioned at the closing part C by widening the gap between the closing parts C in advance to allow some leeway, and then the closing unit 6 can close both bridge girders 2, 2' by narrowing the gap between the closing parts C. At this time, the slide jig 10 is used to apply a horizontal force directly to the bridge girder 2 to slide the bridge girder 2, eliminating the need to process the support 7 and preventing damage to the support 7. In addition, the reaction force during sliding is supported by the pier 1, so that the reaction force can be handled simply by appropriately reinforcing the pier 1 with reinforcing bars, etc.

In addition, the sliding jig 10 is configured to apply a horizontal force to the protrusion 21 on the side of the bridge girder 2, so that the sliding jig 10 can be installed on the side of the bridge girder 2, which has a relatively large and less restricted space, making construction easier.

The slide jig 10 has a relatively simple structure with jacks 12 and 13 attached to a stand 11 consisting of the beam 111 and supports 112 and 113, and can be formed using readily available general-purpose products such as H-shaped steel and hydraulic jacks, eliminating the need for special or dedicated parts.

In addition, in this embodiment, since a horizontal force is applied directly to the bridge girder 2, the rubber bearings (bearings 7) supporting the bridge girder 2 deform as the bridge girder 2 retreats. The deformation caused by the retreat of the bridge girder 2 is within the range that is normally acceptable for seismic isolation type rubber bearings, and no damage or the like occurs.

However, the present invention is not limited to the above-mentioned embodiments. For example, the shape of the bridge girders 2, 2' is not particularly limited, and their cross-sectional shapes, etc. may vary. Furthermore, the type of bridge is not limited to a cable-stayed bridge.

The configuration of the slide jig 10 is also not limited to that described in FIG. 3 etc., as long as it is equipped with a reaction part for supporting a reaction force on the pier 1 and a force application part for directly applying a horizontal force to the girder 2.

As an example, as shown in the slide jig 10a in Figure 6, it is possible to attach a bracket 15 as a reaction part to the top surface of the pier 1, and fix the main body of a center hole jack 17 as a force application part to the bracket 15. The rod of the center hole jack 17 is attached to another bracket 16. This bracket 16 is fixed to the bottom surface of the bridge girder 2.

In the example of Figure 6, by retracting the rod of the center hole jack 17 toward the main body, a horizontal force is applied directly to the bridge girder 2, causing the bridge girder 2 to retreat to the side span side (corresponding to the left side of Figure 6) as indicated by arrow a. To move the bridge girder 2 forward, a slide jig 10a similar to that in Figure 6 can be installed in a different location with the brackets 15, 16 swapped front to back, and a horizontal force can be applied to the bridge girder 2 in the opposite direction to that in Figure 6 using that slide jig 10a.

As such, there are no particular limitations on the shape or configuration of the slide jig. In addition, as shown in the example of Figure 6, where the slide jig 10a is placed between the top surface of the pier 1 and the bottom surface of the bridge girder 2, there are no particular limitations on the position of the slide jig.

The above describes preferred embodiments of the present invention with reference to the attached drawings, but the present invention is not limited to these examples. It is clear that a person skilled in the art can come up with various modified or revised examples within the scope of the technical ideas disclosed in this application, and it is understood that these also naturally fall within the technical scope of the present invention.

Reference Signs List 1: Pier 2, 2': Bridge girder 3: Main tower 4: Diagonal member 5: Lifting device 6: Closing unit 7: Support 10, 10a: Slide jig 11: Frame 12, 13: Jack 21: Protrusion C: Closing section

Claims (5)

A bridge construction method for constructing a bridge by closing bridge girders with a closing unit disposed at a closing section, comprising the steps of:
A step of retracting one of the bridge girders to widen the gap of the closing portion;
placing a closure unit on the closure section;
A step of moving the one bridge girder forward to return the gap of the closing portion to its original size and closing the bridge girders together with the closing unit;
having
When the one bridge girder retreats and advances, a reaction force is supported on the bridge pier by the reaction part of the slide jig, and a horizontal force is directly applied to the one bridge girder by the force application part of the slide jig, thereby sliding the one bridge girder relative to the bridge pier ,
The slide jig is provided with the reaction part and the force application part on a beam member arranged in the bridge axis direction,
A bridge construction method characterized in that a rail for moving the beam material in a direction perpendicular to the bridge axis is provided on the top surface of the pier . A bridge construction method for constructing a bridge by closing bridge girders with a closing unit disposed at a closing section, comprising the steps of:
A step of retracting one of the bridge girders to widen the gap of the closing portion;
placing a closure unit on the closure section;
A step of moving the one bridge girder forward to return the gap of the closing portion to its original size and closing the bridge girders together with the closing unit;
having
When the one bridge girder retreats and advances, a reaction force is supported on the bridge pier by the reaction part of the slide jig, and a horizontal force is directly applied to the one bridge girder by the force application part of the slide jig, thereby sliding the one bridge girder relative to the bridge pier ,
The force application unit applies a horizontal force to a protrusion on a side surface of the one bridge girder,
The slide jig is
A beam member is arranged so as to straddle the pier and protrudes in front and behind the pier;
A first support portion provided on the lower surface of the beam material so as to sandwich the pier from the front and rear;
The reaction portion is attached to the first support portion and abuts on the front and rear surfaces of the pier;
A second support portion is provided on the upper surface of the beam member so as to sandwich the protrusion portion from the front and rear;
A jack as the force application unit attached to the second support portion and applying a horizontal force to the protrusion portion;
A method for constructing a bridge, comprising : The one bridge girder is provided on a support of the top surface of the bridge pier,
3. The method for constructing a bridge according to claim 1 or 2, wherein the bearing is a rubber bearing, which is deformed in association with the setback of the one bridge girder. A slide jig for sliding a bridge girder relative to a pier when constructing a bridge by closing bridge girders with a closing unit arranged in a closing section,
A reaction part for supporting a reaction force on the pier;
A force applying unit that applies a horizontal force directly to the bridge girder;
A rail provided on the top surface of the pier;
having
The slide jig is provided with the reaction part and the force application part on a beam member arranged in the bridge axis direction,
A slide jig characterized in that the rail is for moving the beam material in a direction perpendicular to the bridge axis . A slide jig for sliding a bridge girder relative to a pier when constructing a bridge by closing bridge girders with a closing unit arranged in a closing section,
A beam member is arranged so as to straddle the pier and protrudes in front and behind the pier;
A first support portion provided on the lower surface of the beam material so as to sandwich the pier from the front and rear;
A reaction force portion attached to the first support portion and abutting on the front and rear surfaces of the pier for supporting a reaction force on the pier;
A second support portion provided on the upper surface of the beam material so as to sandwich the protrusion portion on the side surface of the bridge girder from the front and rear;
A jack that is attached to the second support and serves as a force applying unit that applies a horizontal force directly to the protrusion;
A slide jig comprising:

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