Hand-operated projecting machine and bridge construction method

Abstract

The present invention provides a launching machine and bridge erection method that can easily avoid interference with bridge piers when using the launching method. [Solution] A hand-launching machine 1 is attached to the leading end of a bridge girder 2 that is launched in the direction of the bridge axis and is launched together with the bridge girder 2, and is characterized by comprising a main body portion 11 that extends in the direction of the bridge axis, and a tensioning mechanism 12 that pulls the leading end of the main body portion 11 toward the base end of the main body portion 11 so that the leading end of the main body portion 11 does not droop. Preferably the tensioning mechanism 12 comprises a first support portion 13 that protrudes upward from the leading end of the main body portion 11, a second support portion 14 provided toward the base end of the first support portion 13, a connecting member 15 that connects the first support portion 13 and the second support portion 14, and a drive unit 16 that pulls the first support portion 13 toward the second support portion 14 via the connecting member 15.

Description

Technical Field

[0001] The present invention relates to a stretching machine and a bridge erection method.

Background Art

[0002] Conventionally, when erecting a bridge girder on a pier, a method called the bent method is used. In the bent method, a bent assembly process, a bridge girder erection process, a bridge girder connection process, and a bent disassembly process are performed. That is, in the bent method, a bent is assembled using a mobile crane at the planned installation position of the bent, and after the bridge girder is connected on the bent, the bent is disassembled at the installation position of the bent using the mobile crane again. However, at a site with a railway line, a river, etc., it is impossible to arrange a bent or a crane, and the bent method cannot be adopted.

[0003] Therefore, a feeding method is used in which a prefabricated bridge girder and a stretching machine connected to the tip of the bridge girder are sequentially delivered to the pier while being fed in the bridge axis direction (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the launching method, the launching machine connected to the tip flexes under its own weight, and reaches the bridge pier with the tip displaced downwards. This means that the height of the launching machine at the destination is lower than when it was launched, which can cause interference with the bridge pier at the launching point. To prevent this, a temporary support platform such as a bent is installed just in front of the bridge pier, and jacks or other devices placed on the temporary support platform are used to displace the tip of the launching machine upwards, thereby avoiding interference between the launching machine and the bridge pier. However, this method presents problems such as the complexity and time-consuming nature of installing and dismantling the temporary support platform.

[0006] This invention was made to solve the above problems, and aims to provide a launching machine and a bridge erection method that can easily avoid interference with bridge piers when performing the launching method. [Means for solving the problem]

[0007] To solve the aforementioned problems, the present invention provides a hand-launching machine that is attached to the leading end of a bridge girder being launched in the bridge axis direction and is launched together with the bridge girder, characterized in that it comprises a main body extending in the bridge axis direction and a tensioning mechanism that pulls the leading end of the main body toward the base end of the main body so that the leading end of the main body does not droop.

[0008] Furthermore, the present invention relates to a bridge erection method using a cannon attached to the leading edge in the direction of launching a bridge girder that is launched in the bridge axis direction and launched together with the bridge girder, comprising: a connection step of connecting the cannon, which has a main body extending in the bridge axis direction and a tensioning mechanism that pulls the leading edge of the main body toward the base end of the main body so that the leading edge of the main body does not sag, to the bridge girder; a height adjustment step of displacing the leading edge of the cannon upward using the tensioning mechanism; a launching step of launching the cannon together with the bridge girder toward the bridge pier with the leading edge of the cannon displaced upward; and a main body support step of supporting the main body on the bridge pier.

[0009] Furthermore, the present invention relates to a bridge erection method using a cannon attached to the leading edge in the direction of launching a bridge girder that is launched in the bridge axis direction and launched together with the bridge girder, comprising: a connecting step of connecting the cannon, which has a main body extending in the bridge axis direction and a tensioning mechanism that pulls the leading edge of the main body toward the base end of the main body so that the leading edge of the main body does not sag, to the bridge girder; a launching step of launching the cannon together with the bridge girder toward the bridge pier; and a main body support step of supporting the main body on the bridge pier, wherein in the launching step, if the bridge pier and the cannon are likely to interfere with each other, the tensioning mechanism is used to displace the cannon upward to avoid interference with the bridge pier.

[0010] According to the present invention, by using a tensioning mechanism that pulls the tip of the main body of the launching machine toward the base end, the tip of the launching machine can be displaced upward. This makes it easy to avoid interference between the launching machine and the bridge pier.

[0011] Furthermore, it is preferable that the tensioning mechanism comprises a first support column that protrudes upward from the tip side of the main body, a second support column provided closer to the base end than the first support column, a connecting member that connects the first support column and the second support column, and a drive unit that pulls the first support column in the direction of the second support column via the connecting member.

[0012] According to the present invention, the hand-operated machine can be displaced upward with a simple configuration.

[0013] Furthermore, it is preferable that the second support column is provided on the bridge girder.

[0014] According to the present invention, tensile work can be performed stably. [Effects of the Invention]

[0015] The present invention provides a launching machine and bridge erection method that can easily avoid interference with bridge piers when performing the launching method. [Brief explanation of the drawing]

[0016] [Figure 1] It is a side view showing a hand-stretching machine according to the first embodiment of the present invention. [Figure 2] It is a side view showing the details of the hand-stretching machine. [Figure 3] It is a plan view showing the details of the hand-stretching machine. [Figure 4] It is a diagram showing the method for erecting a bridge according to the present invention. (a) is a side view showing the height adjustment step of the first step. (b) is a diagram showing the main body support step of the first step. (c) is a diagram showing the height adjustment step of the second step. (d) is a diagram showing the main body support step of the second step. [Figure 5] It is a front view showing the main body support step. [Figure 6] It is a side view showing the main body support step. [Figure 7] It is a diagram showing a conventional feeding method. (a) is a diagram showing the connection step. (b) is a diagram showing feeding the hand-stretching machine towards the pier. (c) is a diagram showing adjusting the height using the temporary bent equipment. (d) is a diagram showing the state where the hand-stretching machine is fed to the next pier. (e) is a diagram showing the state where the height of the hand-stretching machine when fed to the next pier is adjusted using the temporary bent equipment. (f) is a diagram showing the state where the main body is supported when fed to the next pier. [Figure 8] It is a diagram showing the method for erecting a bridge according to the second embodiment of the present invention. (a) is a diagram showing the feeding step of the first step. (b) is a diagram showing the height adjustment step of the first step. (c) is a diagram showing the main body support step of the first step. (d) is a diagram showing the feeding step of the second step. (e) is a diagram showing the height adjustment step of the second step. (f) is a diagram showing the main body support step of the second step.

[0017] <First Embodiment> The hand-stretching machine and the method for erecting a bridge according to the embodiment of the present invention will be described in detail with reference to the drawings. For overlapping members, the description and reference signs may be omitted.

[0018] As shown in Fig. 1, the stretching machine 1 is attached to the tip in the feeding direction of the bridge girder 2 that is fed out in the bridge axis direction. The stretching machine 1 is fed out together with the bridge girder 2 and is supported by the pier 3 at the tip side where the span is to be bridged. After reaching the pier 3 at the final destination point, the stretching machine 1 is disassembled as needed from the tip side.

[0019] The bridge girder 2 is an element that constitutes a bridge by connecting a plurality of them. The stretching machine 1 is attached to the tip of the bridge girder 2, and each bridge girder 2 is sequentially connected on the feeding yard 4. Rails (not shown) are laid on the feeding yard 4, and a carriage 5 that moves on the rails is arranged. The carriage 5 in this embodiment is a self-propelled carriage, but it may also be a follower carriage that runs by receiving power from another source. By arranging the stretching machine 1 and the bridge girder 2 on the carriage 5, they can be fed out in the bridge axis direction.

[0020] As shown in Figs. 5 and 6, facilities such as a supporting part 6 and a feeding device 20 are installed on the pier 3. The supporting part 6 includes a support 6a that supports the bridge girder 2, a pedestal 6b on which the feeding device 20 is placed, and a pedestal receiving part 6c on which the pedestal 6b is placed. The feeding device 20 is a device that can feed out the stretching machine 1 in the bridge axis direction while supporting the lower part of the stretching machine 1. For example, a caterpillar-type feeding device or the like can be used as the feeding device 20.

[0021] (Stretching machine 1) As shown in Figs. 2 and 3, the stretching machine 1 includes a main body part 11 and a tension mechanism 12. The main body part 11 has a truss structure including a pair of upper chord members 11a, 11a arranged at intervals in the direction perpendicular to the bridge axis, a pair of lower chord members 11b, 11b arranged at intervals in the direction perpendicular to the bridge axis, and diagonal vertical members 11c that connect the pair of upper chord members 11a, 11a and the pair of lower chord members 11b, 11b, respectively. The upper chord members 11a and the lower chord members 11b are, for example, H-shaped steel or I-shaped steel.

[0022] As shown in Figure 2, the tensioning mechanism 12 is a device that pulls the tip of the main body 11 toward the base end (bridge girder 2 side) of the main body 11 so that the tip of the main body 11 does not droop. The tensioning mechanism 12 in this embodiment is a device that applies tension toward the base end of the main body 11 so that the tip of the main body 11 is displaced upward. The tensioning mechanism 12 comprises a pair of left and right first support columns 13, a second support column 14, a connecting member 15, and a drive unit 16.

[0023] As shown in Figures 2 and 3, the pair of first support columns 13, 13 are columnar members positioned at the tip of the main body 11 and projecting upward. The first support columns 13, 13 are installed on the upper surfaces of the upper chord members 11a, 11a, respectively. The first support columns 13 are made of, for example, steel. The tip of the first support column 13 and the tip of the main body 11 are joined diagonally using a reinforcing member 17. The reinforcing member 17 can reinforce the first support columns 13. The first support columns 13 are not limited to the structure described above and may have other structures.

[0024] The pair of second support columns 14, 14 are columnar members positioned on the bridge girder 2 and projecting upward. In other words, the second support columns 14 are positioned further back in the bridge axis direction than the first support column 13. The second support columns 14 are formed of, for example, steel. The tips of the second support columns 14 and the bridge girder 2 are joined diagonally using a reinforcing member 18. The reinforcing member 18 can reinforce the second support columns 14. The second support columns 14 are not limited to the structure described above and may have other structures. In this embodiment, the second support columns 14 are positioned on the bridge girder 2, but only need to be positioned further back in the bridge axis direction than the first support column 13, and may also be positioned on the main body 11.

[0025] The connecting member 15 is a member that connects the first support column 13 and the second support column 14, and is, for example, a PC cable. The drive unit 16 is, for example, a hydraulic jack, with one end connected to the second support column 14 and the other end connected to the connecting member 15. In other words, the drive unit 16 is positioned between the second support column 14 and the connecting member 15. By operating the drive unit 16, the tensile force acting on the connecting member 15 can be controlled. In other words, the drive unit 16 can pull the upper end of the first support column 13 toward the second support column 14 via the connecting member 15. The resulting bending moment can displace the tip of the hand-operated machine 1 upwards.

[0026] Furthermore, the phrase "to prevent the tip from drooping" in the claim includes not only maintaining the height of the tip of the main body 11 at a horizontal position and a position higher than the horizontal position, but also maintaining a height position below the horizontal position, in order to prevent the tip of the main body 11 from drooping.

[0027] (Bridge construction method) Next, the bridge erection method according to this embodiment will be described with reference to Figures 1 to 6. In this embodiment, a first step and a second step are performed. The first step is the step of erecting the bridge between the first pier 3 and the second pier 3 as viewed from the launching yard 4. The second step is the step of erecting the bridge between the second pier 3 and the third pier 3 as viewed from the launching yard 4. In this embodiment, three piers 3 are shown as an example, but there may be two or more piers 3. The bridge erection method related to the first step is performed as follows: a connection step, a height adjustment step, a launching step, and a main body support step.

[0028] As shown in Figure 1, the connection process involves placing the hand-operated machine 1 on the trolley 5 and connecting the bridge girder 2 to the rear end of the hand-operated machine 1.

[0029] As shown in Figure 4(a), the height adjustment process involves using the tension mechanism 12 to pull the tip of the main body 11 toward the base so that the tip of the hand-launching machine 1 is displaced upward. More specifically, the drive unit 16 (hydraulic jack) is activated to pull the connecting member 15 toward the second support column 14 and apply tension. As a result, the first support column 13 connected to the connecting member 15 is pulled toward the base, causing the tip of the main body 11 to be displaced upward. The extent to which the tip of the main body 11 is raised upward (what height position is maintained) can be appropriately set according to the length between the bridge piers 3, 3, the height of the bridge piers 3 or the support 6, the mass of the main body 11, the performance of the connecting member 15 and the drive unit 16, etc. In this embodiment, the hand-launching machine 1 is displaced above the horizontal position when the delivery process is performed.

[0030] As shown in Figure 4(b), the launching process involves moving a trolley 5 that moves along the rails to launch the extension machine 1 and bridge girder 2 to the bridge pier 3. In the launching process, the extension machine 1 is launched in the direction of the bridge axis until the main body 11 reaches the second bridge pier 3. Once the main body 11 reaches the bridge pier 3, the drive unit 16 is activated to loosen the tension of the connecting member 15, causing the tip of the main body 11 to slowly displace downwards. The main body support process is the process of supporting the main body 11 of the hand-launching machine 1 on the bridge pier 3, as shown in Figure 4(b). More specifically, in the main body support process, the tip of the main body 11 is supported by the feeding device 20 (see also Figures 5 and 6).

[0031] After the main support process is completed, the launching device 20 is used to further launch the hand-operated machine 1 and the bridge girder 2 in the direction of the bridge axis. This installs the bridge girder 2 between the first pier 3 and the second pier 3. This completes the first process, and the second process is then carried out.

[0032] The bridge erection method in the second stage involves a height adjustment stage, a launching stage, and a main body support stage. Since each stage is generally the same as in the first stage, detailed explanations will be omitted.

[0033] As shown in Figure 4(c), in the height adjustment process, the tip of the hand-launching machine 1 is displaced upward again using the tensioning mechanism 12 before the machine is launched. As shown in Figure 4(d), in the launching process, the hand-launching machine 1 is launched from the second pier 3 towards the third pier 3.

[0034] As shown in Figure 4(d), in the main body support process, the main body 11 is temporarily supported on the third bridge pier 3. Subsequently, the bridge girder 2 is erected between the second and third piers 3 while the launching machine 1 is moved in the direction of the bridge axis. The launching machine 1 is then sequentially dismantled while being moved in the direction of the bridge axis. Finally, the bridge girder 2 is placed on the support 6a to complete the process.

[0035] Here, we will explain a conventional bridge erection method using the launching method. Figure 7 shows a diagram of the conventional launching method. As shown in Figure 7(a), a launching machine 101 is placed on a trolley 5 and a bridge girder 2 is connected to the rear end of the launching machine 101. As shown in Figure 7(b), when the launching machine 101 and bridge girder 2 are launched towards the second bridge pier 3, the launching machine 101 sags under its own weight, and by the time the tip of the launching machine 101 reaches the second bridge pier 3, the height of the launching machine 101 is lower than that of the bridge pier 3. Therefore, as shown in Figure 7(c), a bent device 107 is installed in front of the bridge pier 3, and the height is adjusted by jacking up the launching machine 101 on the bent device 107. Furthermore, as shown in Figure 7(d), when reaching the third pier 3, the cantilever machine 101 would bend again, so it was necessary to install the bent equipment 107 again in front of the third pier 3, as shown in Figure 7(e). In other words, it was necessary to install the bent equipment 107 at each pier 3 and then dismantle the bent equipment 107 after the work was completed, as shown in Figure 7(f). Thus, attempting to avoid interference between the cantilever machine 101 and the piers 3 using the bent equipment 107 presented problems in terms of both cost and time. In addition, in some cases, it may be difficult to install the bent equipment 107 in front of the piers 3.

[0036] In contrast, the cannonball machine 1 according to this embodiment is equipped with a tensioning mechanism 12 that pulls the tip of the main body 11 toward the base end of the main body 11 to prevent the tip of the main body 11 from drooping. In other words, by using the tensioning mechanism 12 to pull the tip of the main body 11 of the cannonball machine 1 toward the base end of the main body 11, the tip of the cannonball machine 1 can be displaced upward. Therefore, there is no need to separately provide a temporary support (bent equipment) in front of the bridge pier 3, and interference between the cannonball machine 1 and the bridge pier 3 can be easily avoided.

[0037] Furthermore, the bridge erection method of this embodiment includes a connection step of connecting the launching machine 1 and the bridge girder 2, a height adjustment step of displacing the tip of the launching machine 1 upward using the tensioning mechanism 12, a sending step of sending the launching machine 1 toward the bridge pier 3 together with the bridge girder 2 while the tip of the launching machine 1 is displacing upward, and a main body support step of supporting the main body 11 on the bridge pier 3. This makes it easy to avoid interference between the launching machine 1 and the bridge pier 3, similar to the effects described above.

[0038] Furthermore, the tensioning mechanism 12 includes a first support column 13 that protrudes upward from the tip of the main body 11, a second support column 14 provided closer to the base end than the first support column 13, a connecting member 15 that connects the first support column 13 and the second support column 14, and a drive unit 16 that pulls the first support column 13 toward the second support column 14 via the connecting member 15. This allows the hand-launching machine to be displaced upward with a simple configuration.

[0039] Furthermore, since the second support column 14 is provided on the bridge girder 2, tensioning operations can be performed more safely than if it were provided on the tip side of the main body 11. In addition, by providing the first support column 13, the second support column 14, and the connecting member 15 in pairs on the left and right sides of the main body 11, tensioning operations can be performed more stably.

[0040] <Second Embodiment> Next, a second embodiment of the present invention will be described with reference to Figure 8. The bridge erection method according to this embodiment differs from the first embodiment in that the launching machine 1 is initially sent to the bridge pier 3 in a horizontal state without being displaced upward. The bridge erection method according to the first step of this embodiment includes a connection step, a sending step, a height adjustment step, and a main body support step. In other words, the timing of the height adjustment differs from that of the first embodiment. The structure of the launching machine 1 is the same as that of the first embodiment, so its description will be omitted. Also, the operation of each step is generally the same as that of the first embodiment, so a detailed explanation will be omitted.

[0041] First, as shown in Figure 1, a connection process is performed to connect the bridge girder 2 to the rear end of the extension machine 1. After that, a launching process is performed. In the launching process of this embodiment, the extension machine 1 is launched towards the bridge pier 3 while in a horizontal position. As shown in Figure 8(a), in the launching process, the extension machine 1 is launched in the direction of the bridge axis until the main body 11 is positioned slightly in front of the second bridge pier 3. At this time, the main body 11 of the extension machine 1 is in a cantilevered state and bends due to its own weight, and its tip is displaced below horizontal.

[0042] As shown in Figure 8(b), in the height adjustment process, if the extension machine 1 and the pier 3 are likely to interfere with each other, the drive unit 16 (see Figure 2) is activated to pull the connecting member 15 toward the second support column 14, applying tension and displacing the tip of the main body 11 upward to a height where the extension machine 1 does not interfere with the pier 3. As shown in Figure 8(c), in the main body support process, once the tip of the main body 11 has passed the second pier 3, the tension is released and the main body 11 is displaced downward until it is in a horizontal position. Once the main body 11 is in a horizontal position, it is supported on the second pier 3.

[0043] After the main support process is completed, the launching machine 1 and the bridge girder 2 are further launched in the bridge axis direction using the launching device 20 (see Figure 5). This installs the bridge girder 2 between the first pier 3 and the second pier 3. This completes the first process, and the second process is then carried out.

[0044] The bridge erection method in the second stage involves a launching stage, a height adjustment stage, and a main body support stage. Since each stage is generally the same as in the first stage, detailed explanations will be omitted.

[0045] As shown in Figure 8(d), in the second step of the launching process, the hand-launching machine 1 is launched horizontally from the second pier 3 towards the third pier 3. At this time, the main body 11 of the hand-launching machine 1 is in a cantilevered state and bends due to its own weight, and its tip is displaced below horizontal.

[0046] As shown in Figure 8(e), in the height adjustment process, if the tip of the extension machine 1 is likely to interfere with the bridge pier 3, the tension mechanism 12 is used to displace it upward. In the second process, the main body support process, as shown in Figure 8(f), once the tip of the main body 11 exceeds the third bridge pier 3, the tension is released and the main body 11 is displaced downward until it is in a horizontal position. Once the main body 11 is in a horizontal position, it is supported on the bridge pier 3. Subsequently, the bridge girder 2 is erected between the second and third piers 3 while the launching machine 1 is moved in the direction of the bridge axis. The launching machine 1 is then sequentially dismantled while being moved in the direction of the bridge axis. Finally, the bridge girder 2 is placed on the support 6a to complete the process.

[0047] According to the bridge erection method described above, the process involves connecting the hand-operated machine 1 and the bridge girder 2, The process involves a launching step in which the hand-launching machine 1 is sent out toward the bridge pier along with the bridge girder 2, and a main body support step in which the main body 11 is supported on the bridge pier 3. If the hand-launching machine 1 is likely to interfere with the bridge pier 3 during the launching step, the tensioning mechanism 12 is used to displace the hand-launching machine upward. This makes it possible to avoid interference between the hand-launching machine 1 and the bridge pier 3, similar to the first embodiment.

[0048] Although embodiments of the present invention have been described above, the design can be modified as appropriate without violating the spirit of the invention. While the example given shows the arrangement of support sections and launching devices on a bridge pier, for example, if the space on the bridge pier is narrow, brackets or the like for installing these facilities can be placed on the sides of the bridge pier to increase the surface area of ​​the top surface of the bridge pier. In this embodiment, the tensioning mechanism 12 consists of a first support section 13, a second support section 14, a connecting member 15, and a drive section 16, and is provided in pairs on the left and right, but it may be one set or three or more sets. [Explanation of Symbols]

[0049] 1. Hand-rolling machine 2 Bridge girders 3 Bridge piers 4. Dispatch Yard 5 carts 6 Bearing part 11 Main body 12. Geometric mechanisms 13 First support section 14 Second support section 15 Connecting member 16 Drive unit

Claims

1. A hand-launching machine attached to the leading end of a bridge girder being launched in the direction of the bridge axis, and which is launched together with the bridge girder, The main body extends in the direction of the bridge axis, A hand-operated machine characterized by comprising a tensioning mechanism that pulls the tip side of the main body toward the base end side of the main body so that the tip of the main body does not droop.

2. The tensioning mechanism includes a first support column that protrudes upward from the tip of the main body, A second support column is provided on the base end side of the first support column, A connecting member that connects the first support column and the second support column, The hand-operated machine according to claim 1, further comprising a drive unit that pulls the first support column in the direction of the second support column via the connecting member.

3. The hand-launching machine according to claim 2, characterized in that the second support column is provided on the bridge girder.

4. A bridge erection method using a hand-launching machine attached to the leading end of a bridge girder being launched in the direction of the bridge axis, and which is launched together with the bridge girder, A connecting process for connecting a hand-operated extension machine, which has a main body extending in the direction of the bridge axis and a tensioning mechanism that pulls the tip of the main body toward the base end of the main body so that the tip of the main body does not droop, to the bridge girder, A height adjustment step in which the tip portion of the hand-operated machine is displaced upward by the tensioning mechanism, A sending process in which the tip of the hand-launching machine is displaced upward and the hand-launching machine is sent toward the bridge pier together with the bridge girder, A bridge erection method characterized by comprising a main body support step of supporting the main body on the bridge pier.

5. A bridge erection method using a hand-launching machine attached to the leading end of a bridge girder being launched in the direction of the bridge axis, and which is launched together with the bridge girder, A connecting process for connecting a hand-operated extension machine, which has a main body extending in the direction of the bridge axis and a tensioning mechanism that pulls the tip of the main body toward the base end of the main body so that the tip of the main body does not droop, to the bridge girder, A sending process in which the hand-launching machine is sent towards the bridge pier together with the bridge girder, The process includes a main body support step for supporting the main body on the bridge pier, A bridge erection method characterized in that, in the aforementioned launching process, if the launching machine is likely to interfere with the bridge pier, the tensioning mechanism is used to displace the launching machine upward to avoid interference with the bridge pier.

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