Bridge erection method, bridge, and bridge girder module

Abstract

To provide a bridge erection method, a bridge, and a bridge girder module that can immediately erect a bridge without requiring a facility for moving a bridge girder in a launching direction. A main girder 11 of a bridge body 10 is formed by connecting a plurality of girder modules 12 in a bridge axis direction at a erection site, the plurality of girder modules 12 having a predetermined length and being provided with wheels 13 that can travel on the ground, and the bridge body 10 is launched and built in the bridge axis direction from a bridge source to a bridge destination while causing the bridge body 10 to travel on the wheels 13. Therefore, the bridge body 10 can be launched by causing the bridge body 10 to directly travel on the ground, without providing a yard facility for moving the bridge body 10 in the launching direction with a trolley at the site.

Description

BRIDGE ERECTION METHOD, BRIDGE, AND BRIDGE GIRDER MODULE

[0001] The present invention relates to a bridge erection method, a bridge, and a bridge girder module for erecting an emergency bridge that is installed at the time of, for example, a disaster and the like.

[0002] In these years, when an existing bridge is damaged by, for example, flooding due to heavy rain or a major earthquake, traffic is blocked until the bridge is restored, which will have a significant influence on the lives of local residents and the like. Additionally, although it requires a long period of time for erection work for re-erecting or restoring a bridge, if traffic remains blocked, rescue operations and transportation of goods will be hindered.

[0003] Therefore, it is desired as one of the countermeasures against disasters to build an emergency bridge that can be erected in a short period of time to temporarily allow traffic.

[0004] As a method of erecting such an emergency bridge, for example, as in conventional launching methods, it is necessary to launch a bridge girder in a bridge axis direction from a construction yard so that the bridge girder reaches an opposite shore, thereby enabling erection on site, such as a river, where a temporary gantry, a crane, and the like cannot be arranged under girders.

[0005] As a conventional launching method, it is known to attach a launching nose extending in the bridge axis direction at a tip of a bridge girder in a launching direction, to launch the bridge girder by using equipment such as a jack, and to launch the bridge girder toward the bridge destination while supporting a tip side of the launching nose body by a launching device installed on an abutment or a pier (for example, refer to PTL 1).

[0006] Japanese Patent Publication 2018-178572

[0007] In the aforementioned launching method, since a dedicated yard facility is installed at a launching source, and a bridge girder is placed on a trolley provided on the yard facility to cause the trolley to travel in the bridge axis direction, a step of installing the yard facility is required before a launching step of the bridge girder. However, since it is required for an emergency bridge to be immediately erected, there has been a problem in that when the erection period for the installation step of the yard facility takes time, the completion of the emergency bridge is delayed.

[0008] The present invention has been made in view of the aforementioned problem, and an object of the present invention is to provide a bridge erection method, a bridge, and a bridge girder module that can immediately erect a bridge without requiring a facility for moving a bridge girder in a launching direction.

[0009] In order to achieve the aforementioned object, in the present invention, in a bridge erection method of launching and building a bridge body including a main girder in a bridge axis direction from a bridge source to a bridge destination, the main girder of the bridge body is formed by connecting a plurality of girder modules in the bridge axis direction at an erection site, the plurality of girder modules having a predetermined length and being provided with wheels that can travel on the ground, and the bridge body is launched and built in the bridge axis direction from the bridge source to the bridge destination while causing the bridge body to travel on the wheels.

[0010] Accordingly, the main girder of the bridge body is formed by connecting the plurality of girder modules in the bridge axis direction at the erection site, and the bridge body is launched in the bridge axis direction from the bridge source while causing the bridge body to travel on the wheels so that the bridge body is built to the bridge destination. Therefore, it becomes possible to launch the bridge body by causing the bridge body to directly travel on the ground, without providing a yard facility for moving the bridge body in the launching direction with a trolley at the site. Additionally, the girder modules of the same length are combined to from the main girder by using as many girder modules as the length of the main girder. Therefore, when a disaster occurs, erection work can be quickly started by conveying the prefabricated girder modules to a site.

[0011] According to the present invention, the bridge body can be launched by causing the bridge body to directly travel on the ground, without providing a yard facility for moving the bridge body in the launching direction with a trolley at the site. Therefore, since it becomes unnecessary to bring in and assemble materials used for the yard facility, the erection period can be reduced, and an emergency bridge can be immediately erected. Accordingly, even when an existing bridge girder is damaged by, for example, flooding due to heavy rain or a major earthquake, an emergency bridge can be quickly erected and traffic can be restored, and thus it is possible to contribute to enforcement of countermeasures against disasters, such as rescue operations and transportation of goods. On that occasion, since each girder module can travel independently, the movement and connection operations of girder modules can be easily performed at the site. Additionally, since erection work can be quickly started by conveying prefabricated girder modules to the site when a disaster occurs, a preparation period can be significantly reduced without individually designing a bridge girder, and an emergency bridge can be rapidly erected.

[0012] Fig. 1 is a side view of a girder module illustrating a first embodiment of the present invention.Fig. 2 is a side view of the girder module arranged on both ends of a main girder in a bridge axis direction.Fig. 3 is a plan view of the girder module.Fig. 4 is a front view of the girder module.Fig. 5 is partial side view of a bridge body.Fig. 6 is a partial plan view of the bridge body.Fig. 7 is a side view of the girder module illustrating a container accommodation state.Fig. 8 is front view of the girder module illustrating the container accommodation state.Fig. 9 is side view illustrating a bridge erection step.Fig. 10 is a side view illustrating the bridge erection step according to a second embodiment of the present invention.Fig. 11 is a side view illustrating the bridge erection step according to a third embodiment of the present invention.Fig. 12 is a side view illustrating a part of the bridge erection step according to a fourth embodiment of the present invention.

[0013] Fig. 1 to Fig. 9 illustrate a first embodiment of the present invention, and illustrate a bridge erection method for erecting an emergency bridge that is installed at the time of, for example a disaster or the like.

[0014] The emergency bridge illustrated in the figures consists of a bridge body 10 that is built over an existing abutment 1, and a plurality of deck panels 20 placed on a bridge girder 2 in the bridge axis direction, and the bridge body 10 includes a pair of main girders 11 that are spaced apart from each other in a direction perpendicular to the bridge axis direction. Note that, in the present embodiment, a status is illustrated where the bridge girder is damaged by, for example, a disaster and the like, and only the abutment 1 remains.

[0015] The main girder 11 consists of a plurality of girder modules 12 that can be connected to each other in the bridge axis direction, and the girder modules 12 are provided with wheels 13 that can travel on the ground.

[0016] Each girder module 12 is formed in a plate girder shape with steel materials consisting of an upper flange 12a, a lower flange 12b, and a web 12c, each being formed to have a predetermined length (for example, 10 m). Each girder module 12 is connected at its longitudinal ends with connection plates 12d, and the connection plates 12d are fastened to the girder modules 12 with bolts and nuts, which are not illustrated. Among the girder modules 12, an end side of the girder modules 12 arranged at both ends (a leading edge and a trailing edge) in the bridge axis direction is provided with a notch 12e formed such that a part of a bottom surface (lower flange 12b) of the girder module 12 becomes higher than the other portion as illustrated in Fig. 2. The notch 12e is formed such that the lower flange 12b is formed to be parallel to an upper flange 12a on its end side in the bridge axis direction, and to be inclined downward toward the direction opposite to the end side.

[0017] The wheels 13 are arranged at two locations of the girder module 12 in a longitudinal direction, respectively, and each pair is provided at the lower flange 12b of the girder module 12 in a width direction. The wheels 13 are arranged on the sides of the lower flange 12b, and are attached to both ends of an axle 13a, respectively, and the axle 13a is rotatably supported by a bearing 13b provided in a bottom surface of the lower flange 12b. A reinforcing plate 13c is provided above the bearing 13b, and the reinforcing plate 13c is fixed to an upper surface of the lower flange 12b and to a side surface of the web 12c.

[0018] Next, the bridge erection method of the present embodiment will be described with reference to Fig. 9 (A) to Fig. 9 (E).

[0019] First, a plurality of girder modules 12 are carried in to a erection site, and the bridge body 10 is assembled that corresponds to the span length (for example, 50 m) between the abutments 1. In the case of the present embodiment, the girder modules 12 are connected to form one main girder 11, and the bridge body 10 is formed by connecting a pair of main girders 11 with a space apart in the direction perpendicular to the bridge axis direction with a plurality of horizontal girders 14.

[0020] Subsequently, as illustrated in Fig. 9 (A), a launching nose 15 is attached to a tip of each main girder 11, and the bridge body 10 is arranged at a bridge source. On that occasion, a suspension device 16 for hanging the bridge body 10 is installed in the launching nose 15. The launching nose 15 is formed by a truss-shaped steel structure extending in the bridge axis direction, and is connected to the main girder 11 such that a bottom surface of the launching nose 15 is flush with a bottom surface of the bridge body 10.

[0021] Next, as illustrated in Fig. 9 (B), a rear girder 17 is arranged behind the bridge body 10, and the rear girder 17 is connected to a rear end of each main girder 11. The rear girder 17 is formed by connecting a plurality of girder modules 12, and the number of the girder modules 12 used as the rear girder 17 corresponds to the area of a backyard. On that occasion, when the length of the rear girder 17 becomes shorter than the main girder 11, a counterweight, which is not illustrated, is placed on the rear girder 17 to increase the weight of the rear girder 17. Note that a deck panel 20 may be used instead of the counterweight. Additionally, the suspension device 16 for hanging the bridge body 10 is installed in the rear girder 17.

[0022] Thereafter, a rear end of the rear girder 17 is pressed by a heavy machinery 2, thereby launching the bridge body 10 toward a bridge destination while causing the bridge body 10 to travel on the wheels 13, and after the launching nose 15 of the bridge body 10 reaches the bridge destination as illustrated in Fig. 9 (C), the launching nose 15 is supported by a stand 3 installed at the bridge destination.

[0023] Next, as illustrated in Fig. 9 (D), the bridge body 10 is lowered from the launching nose 15 and the rear girder 17 onto each of the abutments 1 by the suspension device 16. On that occasion, the notches 12e of the girder modules 12 are supported by the abutments 1.

[0024] Thereafter, as illustrated in Fig. 9 (E), the erection of the emergency bridge is completed by placing the deck panels 20 on the bridge body 10. On that occasion, the deck panels 20 are sequentially installed up to the bridge destination by installing the deck panels 20 on the bridge body 10 from the bridge source by using a crane truck, which is not illustrated, and performing an installation operation by bringing the crane truck onto the installed deck panels 20. Note that a steel lining plate (ready-made article) may be used for the deck panel 20, or precast concrete may be used for the deck panel 20.

[0025] In this manner, according to the present embodiment, the plurality of girder modules 12 having the predetermined length and provided with the wheels 13 that can travel on the ground are connected in the bridge axis direction at the erection site to form the main girder 11 of the bridge body 10, and the bridge body 10 is launched and built from the bridge source to the bridge destination in the bridge axis direction while causing the bridge body 10 to travel on the wheels 13. Accordingly, it is possible to launch the bridge body 10 by causing the bridge body to directly travel on the ground, without providing a yard facility for moving the bridge body 10 in the launching direction with a trolley at the site. Therefore, since it becomes unnecessary to bring in and assemble materials used for the yard facility, the erection period can be reduced, and an emergency bridge can be immediately erected. On that occasion, since each girder module 12 can travel independently, the movement and connection operations of girder modules 12 can be easily performed at the site.

[0026] Accordingly, even when an existing bridge girder is damaged by, for example, flooding due to heavy rain or a major earthquake, an emergency bridge can be quickly erected and traffic can be restored, and thus it is possible to contribute to enforcement of countermeasures against disasters, such as rescue operations and transportation of goods.

[0027] Additionally, since the plurality of girder modules 12 having the predetermined length are connected in the bridge axis direction at the site, the Girder modules 12 of the same length are combined to from the main girder 11 by using as many girder modules 12 as the length of the main girder 11. Accordingly, since erection work can be quickly started by conveying prefabricated general-purpose girder modules 12 to the site when a disaster occurs, a preparation period can be significantly reduced without individually designing a bridge girder, and an emergency bridge can be rapidly erected.

[0028] Note that, when utilizing existing abutments, there is a case where a multiple of the length of the girder module 12 does not match the span length. However, in that case, the length of the main girder can be adjusted to match the span length between the abutments by separately manufacturing only the girder module 12 having a fractional length, or cutting the ready-made girder module 12 to change the length.

[0029] Additionally, in the present embodiment, the launching nose 15 extending in the bridge axis direction is attached to the tip of the main girder 11, and the main girder 11 is launched and the launching nose 15 is supported at the bridge destination. Therefore, the bending moment that occurs at the time of launching of the main girder 11 can be reduced, and deflection due to the self-weight of the main girder 11 can be decreased.

[0030] Further, since the rear girder 17 extending in the bridge axis direction is connected to the rear end of the main girder 11 in the launching direction, the main girder 11 can be launched to the bridge destination in a cantilever state while being supported by the rear girder 17. On that occasion, by temporarily placing, on the rear girder 17, the deck panels 20 to be placed on the main girder 11, the deck panels 20 can be utilized as the counterweight, and the weight of the rear girder 17 can be increased without preparing a dedicated counterweight.

[0031] Additionally, since the rear girder 17 is formed by the plurality of girder modules 12, the girder module 12 can be used for all of the main girder 11 and the rear girder 17. Accordingly, it is unnecessary to prepare a dedicated rear girder, and the number of kinds of members to be used for erection of an emergency bridge can be reduced.

[0032] Further, since the main girder 11 is launched by pressing the main girder 11 with the heavy machinery 2, driving equipment, such as a hydraulic jack, for moving the main girder 11 is not required, and the equipment to be carried in to the site can be decreased. For example, a small bulldozer and the like that are used for leveling and the like of the spot can be used as the heavy machinery 2.

[0033] Additionally, in the present embodiment, for example, by forming one girder module 12 to have a length dimension L of 10 m and a height dimension H of approximately 1.8 m, two girder modules 12 can be accommodated side-by-side in a container 4, which is formed by, for example, an ISO-standard 40-foot container (a length L1 of inner dimension is 11,998 mm, a width W2 is 2,330 mm, and a height H1 is 2,350 mm), as illustrated in Fig. 7 and Fig. 8. Accordingly, since marine transportation by container ship becomes possible, conveying to remote places and islands can be easily performed, and a wide range of responses can be performed when a disaster occurs.

[0034] Note that, although the aforementioned embodiment illustrates the main girder 11 to which the launching nose 15 and the rear girder 17 are connected, the present invention can also be applied to a case where the launching nose 15 or the rear girder 17 is not used.

[0035] Additionally, although the aforementioned embodiment illustrates the main girder 11 in which the girder modules 12 having the notch 12e are arranged at both ends of the main girder 11 in the bridge axis direction, the main girder 11 may be formed only by the girder modules 12 without the notch 12e.

[0036] Further, although the aforementioned embodiment illustrates the girder module 12 formed into the I-shaped plate girder shape, the girder module 12 may be formed into a box girder shape.

[0037] In addition, the present invention can be applied not only to an emergency bridge, but also to a case where a bridge is erected as a permanent bridge.

[0038] Fig. 10 (A) to Fig. 10 (E) illustrate a second embodiment of the present invention, and the components that are equivalent to those in the first embodiment are designated and illustrated by the same numerals.

[0039] Although the first embodiment illustrates the bridge body 10 that is erected on the existing abutments 1, in the present embodiment, the bridge body 10 is directly erected over the ground 5 such as riverbanks. Note that, since the erection step illustrated in Fig. 10 (A) to Fig. 10 (E) is the same as that in the first embodiment, a description is omitted.

[0040] According to the present embodiment, since the bridge body 10 is directly erected over the ground 5, the bridge body 10 can be erected at an arbitrary location, irrespective of the existence of an existing bridge. On that occasion, since the notch 12e of the girder module 12 is formed to be inclined downward toward the direction opposite to the tip of the main girder 11, the notch 12e can be arranged along a slope of the ground 5, and interference between the main girder 11 and the ground 5 can be reduced.

[0041] Fig. 11 (A) to Fig. 11 (E) illustrate a third embodiment of the present invention, and the components that are equivalent to those in the first embodiment are designated and illustrated by the same numerals.

[0042] Although the first embodiment illustrates the bridge body 10 that is erected on the existing abutments 1, in the present embodiment, concrete blocks 6 serving as abutments are installed on the ground such as riverbanks, and the bridge body 10 is erected on the blocks 6. Note that, since the erection step illustrated in Fig. 11 (A) to Fig. 11 (E) is the same as that in the first embodiment, a description is omitted.

[0043] According to the present embodiment, since the blocks 6 are installed on the ground to erect the bridge body 10, even when the ground of a erection site is unstable, the bridge body 10 can be stably erected on the blocks 6.

[0044] Fig. 12 (A) to Fig. 12 (C) illustrate fourth to sixth embodiments of the present invention, and the components that are equivalent to those in the first to third embodiments are designated and illustrated by the same numerals.

[0045] Although the first to third embodiments illustrate the bridge body 10 that is launched by being pressed with the heavy machinery 2, in the present embodiment, the bridge body 10 is launched toward the bridge destination by wrapping a wire 7 around a pulley 8 at the bridge destination, one end of the wire 7 being connected to the tip of the launching nose 15, and by towing the other end of the wire 7 with the heavy machinery 2 at the bridge source.

[0046] Note that, in Fig. 12 (A), the launching step in the first embodiment in Fig. 9 is replaced with the fourth embodiment, and in Fig. 12 (B), the launching step in the second embodiment in Fig. 10 is replaced with the fifth embodiment. Additionally, in Fig. 12 (C), the launching step in the third embodiment in Fig. 11 is replaced with the sixth embodiment.

[0047] In this manner, according to the fourth to sixth embodiments, since the tip side of the bridge body 10 is launched by being pulled with the wire 7 toward the pulley 8 at the bridge destination, the bridge body 10 can be always launched toward a reaching point of the bridge destination, and launching work can be easily performed.

[0048] Note that, although the fourth to sixth embodiments illustrate the wire 7 that is towed with the heavy machinery 2 at the bridge source in the direction opposite to the launching direction of the bridge body 10, the heavy machinery 2 may be arranged at the bridge destination, and the wire 7 may be towed with the heavy machinery 2 in the launching direction of the bridge body 10.

[0049] Additionally, the first to sixth embodiments are examples of the present invention, and the present invention is not limited to those described in the aforementioned embodiments.

[0050] 1...abutment, 2...heavy machinery, 9...wire, 3...abutment, 5...ground, 6...block, 7...wire, 10...bridge body, 11...main girder, 12...girder module, 15...launching nose, 17...rear girder, 20...deck panel.

Claims

1. A bridge erection method of launching and building a bridge body including a main girder in a bridge axis direction from a bridge source to a bridge destination, wherein the main girder of the bridge body is formed by connecting a plurality of girder modules in the bridge axis direction at a erection site, the plurality of girder modules having a predetermined length and being provided with wheels that can travel on the ground, and the bridge body is launched and built in the bridge axis direction from the bridge source to the bridge destination while causing the bridge body to travel on the wheels.

2. The bridge erection method according to claim 1, wherein a launching nose extending in the bridge axis direction is attached to a tip of the bridge body in a launching direction, and the bridge body is launched and the launching nose is supported at the bridge destination.

3. The bridge erection method according to claim 1, wherein the bridge body is launched by connecting a rear girder extending in the bridge axis direction to a rear end of the bridge body in a launching direction.

4. The bridge erection method according to claim 3, wherein the rear girder is formed by connecting the plurality of girder modules in the bridge axis direction.

5. The bridge erection method according to claim 3, wherein the bridge body is launched by temporarily placing, on the rear girder, a deck panel to be placed on the bridge body.

6. The bridge erection method according to claim 1, wherein the bridge body is launched by being pressed with a heavy machinery.

7. The bridge erection method according to claim 1, wherein the bridge body is launched by wrapping a wire at the bridge destination, one end of the wire being connected to a tip side of the bridge body, and by towing the other end of the wire with a heavy machinery.

8. A bridge that is erected by launching and building a bridge body including a main girder in a bridge axis direction from a bridge source to a bridge destination, the bridge comprising: a plurality of girder modules that form the main girder of the bridge body by being connected to each other in the bridge axis direction, wherein each of the girder modules is provided with wheels that can travel on the ground.

9. A girder module to be used for a bridge that is erected by launching and building a bridge body including a main girder in a bridge axis direction from a bridge source to a bridge destination, wherein the girder module is configured to be able to form the main girder of the bridge body by being connected to other girder modules in the bridge axis direction, and is provided with wheels that can travel on the ground.

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