JPH0364003B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a method of constructing an arch ring in a concrete arch bridge.

[Prior art]

When constructing an arch ring for a relatively medium-sized concrete arch bridge with a span of 50 m to 100 m over a river, if it is not possible to assemble a ground-type shoring under the arch ring, conventionally, arch center After constructing the bridge between the arch abutments, a formwork was erected over the arch center, and then concrete was poured to form the arch ring.

[Problem that the invention seeks to solve]

According to the above conventional method, once an arch ring is formed, the arch center will be under the arch ring, so the work is to dismantle and remove the arch center from above the arch ring using a tower crane, etc. Because it is extremely complex, it takes many work days and is a factor that increases the construction cost of concrete arch bridges. Although concrete arch bridges use less material and are considered to be a structural type suitable for single-span long bridges, the reason why there are few practical examples is that the construction cost accounts for a large proportion of the overall construction cost. It is said.

[Purpose and structure of the invention]

The object of the present invention is to provide an arch ring construction method for a concrete arch bridge that advantageously solves the above-mentioned drawbacks and can construct a concrete arch bridge at low construction cost. However, an arch center 1 is assembled and erected in advance above the location where the arch ring is to be constructed, and the formwork for arch ring block construction is supported by formwork movement support devices 2 mounted on both sides of the arch center 1. The process of pouring concrete into the formwork and constructing the arch ring block 3, and the process of moving the formwork, which has been removed from the mold after the concrete hardens, using the movable support device 2, are repeated, and the arch ring is erected. The arch ring block 3 in the middle is supported by the arch center 1 via the arch ring hanging material 4, and after the arch ring 5 is completed, the arch ring hanging material 4 is removed and the arch center 1 is dismantled and removed. Arch ring construction method for concrete arch bridges.

〔Example〕

Next, the present invention will be explained in detail using illustrated examples.

FIGS. 7 to 12 show a formwork moving support device 2 used in an embodiment of the present invention, showing an intermediate girder 6, side girders 7 disposed on both left and right sides thereof, and each girder. A large number of sleepers 9 are placed and fixed on the upper surface of the side girder 7 of the steel arch center 1, which is made up of a large number of connecting beams 8 connecting the The wheels 12 of the vehicle body 13 are mounted on the rails 10 and are mounted on the rails 10, and are fixed on the arch center 1. A formwork support frame 14 is disposed below the formwork movement support device 2, and the vehicle body frame 11 includes a plurality of lower frame bodies 1 extending in the left-right direction and arranged at intervals in the front-rear direction.
5, and an upper frame member 16 which extends in the front-rear direction and is arranged at intervals in the left-right direction and is removably fixed to the lower frame member 15 with bolts or the like, and the formwork support frame 14 teeth,
A large number of lower frame members 17 extending in the front-rear direction and arranged at intervals in the left-right direction; A plurality of intermediate frame members 18 are freely fixed, and a large number of upper frame members 19 extend in the front-rear direction, are arranged at small intervals in the left-right direction, and are detachably fixed to the intermediate frame members 18 with bolts or the like. It is composed of.

Frame hanging materials 20 made of steel rods having screws over the entire length are arranged at intervals in the front-rear direction and left-right direction, and the upper part of the frame hanging materials 20 is located between the upper frame members 16 arranged at small intervals. A supporting metal fitting 22 having a semi-cylindrical upper convex surface extending in the left-right direction and a hanging material insertion hole 21 expanding upward is inserted into the upper part of the frame hanging material 20 and is inserted into the upper frame of the adjacent upper frame. A movable support fitting 23 having an arc-shaped lower concave surface that is placed over the upper surface of the material 16 and further extends in the left-right direction is fitted into the upper part of the frame hanging material 20 and is attached to the support metal fitting 22.
A nut 24, which is fitted and mounted so as to be tiltable with respect to the frame hanger 20 and screwed onto the upper part of the frame hanging member 20, is supported by the movable support fitting 23.

The lower part of the frame hanging material 20 is inserted between the lower frame materials 17 arranged at small intervals, and has a semi-cylindrical lower convex surface extending in the left-right direction and a hanging material insertion hole 25 expanding downward. Supporting metal fittings 26
is fitted into the lower part of the frame hanging material 20 and abuts across the lower surface of the adjacent lower frame material 17,
The movable support fitting 27 having an arc-shaped upper concave surface extending in the left-right direction is fitted into the lower part of the frame hanging member 20 and is fitted to the supporting fitting 26 so as to be tiltable, and is further screwed into the lower part of the frame hanging member 20. The movable support fitting 27 is supported by the fitted nut 28.

A bottom formwork 29 is placed over the upper surface of each of the upper frame members 19 and is removably fixed with bolts or the like, and on the upper surfaces of the left and right sides of the bottom formwork 29,
A side formwork 31 provided with a support frame 30 is mounted and removably fixed with bolts or the like, and a front end formwork 33 provided with a support frame 32 is disposed on the upper surface of the front part of the bottom formwork 29. is mounted and removably fixed with bolts or the like, and the bottom formwork 29, side formworks 31, and front formwork 33 constitute a formwork for constructing the arch ring block.

A large number of upper frame members 34 extending in the left-right direction are arranged at intervals in the front-rear direction, and two lower frame members 3 are arranged at both left and right ends of each upper frame member 34.
The upper frame members 34 and lower frame members 35 are removably fixed with bolts or the like, and the scaffolding boards 36
is placed across each upper frame member 34 and removably fixed with bolts or the like, and the upper frame member 34,
Scaffolding 37 consisting of lower frame material 35 and scaffolding board 36
is arranged below the formwork support frame 14,
Further, the lower part of the frame hanging member 20 on the outside of the side girder member 7 is inserted between the left and right lower frame members 35 arranged at small intervals, and the frame is inserted in the same way as when supporting the formwork support frame 14. A lower frame member 35 of a scaffold 37 is supported by a nut 28 screwed onto the hanging member 20 via a movable support metal fitting 27 and a support metal fitting 26.

The front end of a climbing jack 38 made of a hydraulic jack is connected to the rear end of the vehicle body 13 by a pin, and a rail clamp 39 is connected to the rear end of the climbing jack 38 by a pin. A manually operated lever traction machine 40 is connected to the front end, and a rail clamp 42 is connected to the end of a chain 41 wrapped around a load sheave of the traction machine 40.

When moving the formwork moving support device 2 configured in this way from the lower level side of the arch center 1 to the higher level side, the rail 10 is gripped by the rail clamp 39 attached to the climbing jack 38 and the rail 10 is moved from the lower level side to the higher level side of the arch center 1. With the clamp 39 fixed to the rail 10, the climbing jack 38 is extended to move the formwork moving support device 2 to the arch center 1.
Move upward along the line. In this case, in order to prevent the vehicle body 13 from lifting, the chain 4
The rail 10 is gripped by the supporting metal fitting 22 attached to the frame member 1, and the chain 41 is always kept under tension by operating the manually operated lever traction machine 40 as the formwork moving support device 2 moves forward.

When the formwork moving and supporting device 2 is moved along the arch center 1, the angle of the formwork moving and supporting device 2 with respect to the horizontal plane changes depending on the position of the formwork moving and supporting device 2 on the arch center 1. In the case of the embodiment, a support metal fitting 22 having a semi-cylindrical upper convex surface and a movable support metal fitting 23 having an arcuate lower concave surface
Since the upper part of the frame hanging material 20 is suspended and supported via the nut 24, the frame hanging material 20 can be suspended so as to always be in a vertical state.

In addition, even if the formwork support frame 14 and the scaffolding 37 are inclined with respect to the frame hanging material 20, the movable support fittings 27 can be rotated in the front and rear directions relative to the support fittings 26, so that the lower frame material 17 and the lower frame The support metal fitting 26 can always be brought into surface contact with the material 35.

When constructing an arch ring for a concrete arch bridge using this invention, first, as shown in FIG. build,
In addition, an upper end slab 47 is constructed across the upper end of the end post 46 and the abutment 44.

Next, the steel arch center 1 is installed between the arch butts 45 on both banks at a position slightly higher than the position where the arch ring 5 is installed. When constructing this arch center 1, for example, the arch center 1 is divided into a large number of arch center blocks 48, and the arch center blocks 48 are connected from both banks using joint plates 49 and bolts by a known overhang method. Alternatively, arch center 1 may be divided into two blocks,
After the halves of the arch center are assembled on the arch abutments 45 on both banks, the half arch center may be lowered to a predetermined position, and then the opposite ends of each half arch center may be connected to construct the arch center.

Next, below the end of arch center 1,
A post type support 52 consisting of a large number of posts 50 and post connecting members 51 is assembled and installed so as to reach the level of the root of the arch ring, and the post type support 5
2, a frame-type shoring 53 consisting of a large number of supporting frames assembled and connected is assembled and installed up to a height reaching the lower surface of the end of the arch ring 5.

Next, a formwork (not shown) is placed on the frame type shoring 53, and within the formwork, the lower part of the arch ring hanging material 4, which is made of reinforcing bars and a steel rod having screws over its entire length, is placed. A nut 56 screwed onto the upper end of the arch ring hanging member 4 is supported by a support beam 54 installed on the upper surface of the arch center 1, and then concrete is poured into the formwork. , forming an arch ring end block 55.

After the concrete of the arch ring end block 55 hardens and reaches a predetermined strength, a tensioning jack (not shown) such as a center hole jack is inserted into the upper part of the arch ring hanging material 4 and the support beam is inserted. 54, and then a jack engaging nut (not shown) screwed onto the upper end of the arch ring suspension material 4 is engaged with the upper end of the tensioning jack, and the arch ring is suspended by the tensioning jack. With the material 4 under tension, the nut 56 screwed onto the upper part of the arch ring hanging material 4 is tightened to fix the upper part of the arch ring hanging material 4, and then the tensioning jack, the formwork and the framework are tightened. Remove the type shoring 53.

Next, the unfinished section of the arch ring is divided into lengths that are approximately the same as the divided length of the arch center 1, and the arch ring blocks 3 are successively constructed following the arch ring end block 55.

When constructing the arch ring block 3, first, the constituent members of the formwork movement support device 2 are transported by a truck crane 64 or the like, and then the arch center 1 is constructed.
and placed on the post-type shoring 52, as shown in FIG.
As shown in FIGS. 7 and 8, the formwork moving support device 2 is assembled.

Next, a lifting jack such as a center hole jack (not shown) is inserted into the upper part of the frame hanging material 20, placed on the upper frame material 16, and the jack screwed onto the upper end of the frame hanging material 20. A combination nut (not shown) is engaged with the upper end of the lifting jack, and then the lifting jack is used to
Pull up each frame hanging member 20 and each part supported thereby, and bring the rear end of the bottom formwork 29 into close contact with the lower surface of the front end of the arch ring end block 55. In this state, tighten the nuts 24. is tightened and supported by the upper frame member 16 at the upper part of the frame hanging material 20 via the support metal fitting 22, the movable support metal fitting 23, and the nut 24.

Next, with the rear end of the side formwork 31 in contact with the front end side surface of the arch ring end block 55, the side formwork 31 is fixed to the bottom formwork 29, and the left and right side forms The front end formwork 33 disposed between the front ends of the frames 31 is fixed to the bottom formwork 29 and the side formworks 31, and as shown in FIG. The upper parts of a plurality of arch ring hanging members 4 made of steel rods having threads are inserted over the entire length of the supporting beam 54 which is constructed across the timber 7, and are screwed onto the upper ends of the arch ring hanging members 4. The nut 56 is supported by the beam 54.
Supported by

Further, the lower part of the arch ring hanging material 4 is inserted into the internal mold 57 for forming the arch ring hollow part, and the internal mold 57 is supported by a nut 58 screwed into the lower part of the arch ring hanging material 4. Place reinforcing bars in the area surrounded by the frame and concrete 59
to be poured.

After the concrete 59 hardens and reaches a predetermined strength, the side formwork 31, the front end formwork 33, and the internal formwork 57 for forming the arch ring hollow part are demolded, and then the lower end of the arch ring hanging material 4 is removed. The arch ring hanging member 4 is tightened by tightening the nut 58 screwed into the arch ring hanging member 4. When pouring concrete, the weight of the poured concrete 59 is quite large, so in order to prevent the weight of this concrete from acting on the wheels 12, multiple beams placed on the intermediate girder 6 and side girder 7 of the arch center 1 are used. Preferably, the vehicle body 13 is supported by a wedge 60 and a bearing block 61.

Next, a lifting jack such as a center hole jack (not shown) is inserted into the upper part of the frame hanging material 20, and placed on the upper frame material 16, and the jack screwed onto the upper end of the frame hanging material 20. A combination nut (not shown) is engaged with the upper end of the lifting jack, and then, while loosening the nut 24, each frame hanging member 20 and each part supported thereby are loosened by the lifting jack. Descend and
After the bottom formwork 29 is demolded, the formwork moving support device 2 is moved forward to the position where the next arch ring block is to be constructed using the climbing jack 38 and the manually operated lever traction machine 40. Thereafter, the same operation is repeated from both banks to the arch ring block adjacent to the central arch ring block (crown).

Next, after withdrawing one of the formwork moving and supporting devices 2 to the base of the arch, that formwork moving and supporting device 2 is dismantled and removed, and the other formwork moving and supporting device 2 is removed.
is moved to the center of the arch center 1 as shown in FIG. 3, and the center arch ring block is constructed as described above, completing construction of the entire arch ring. Note that when constructing the central arch ring block, the internal formwork 57, arch ring hanging material 4, and front end formwork 33 are not used.

Next, a tensioning jack such as a center hole jack is inserted into the upper part of the arch ring hanging material 4 and placed on the support beam 54, and then a jack engaging nut screwed onto the upper end of the arch ring hanging material 4 is inserted. Engaged with the upper end of the tensioning jack, and with the tensioning jack tensioning the arch ring hanging material 4, loosen the nut 56 screwed onto the upper part of the arch ring hanging material 4, and then loosen the arch ring hanging material 4. After removing the hanging materials 4 and sequentially removing all the arch ring hanging materials 4 in this way, the arch center 1 is dismantled and removed, and then the support is placed on the arch ring 5 as shown in Fig. 4. Assemble the structure and post 6
2 and the remaining upper deck slab 63 are constructed to complete the arch bridge.

When carrying out this invention, the chain 41 of the manually operated lever traction machine 40 may not be fixed to the rail 10 but may be fixed to the arch center 1 by suitable means. In addition, when moving the formwork moving support device 2 forward, there are
Since there is a connecting beam 8 that becomes an obstacle to the movement of the frame hanging material 20, the frame hanging material 20 between the intermediate beam material 6 and the side beam material 7 is removed and the formwork moving support device 2 is moved forward.

〔Effect of the invention〕

According to this invention, the arch center 1 is assembled and erected in advance above the location where the arch ring is to be constructed, and the formwork for arch ring construction is moved by the formwork moving support device 2 mounted on both sides of the arch center 1. The process of supporting the arch ring block 3 by pouring concrete into the formwork, and the process of moving the demolded formwork by the movable support device 2 after the concrete has hardened are repeated.
In addition, since the arch ring block 3 in the middle of being constructed is supported by the arch center 1 via the arch ring hanging material 4, the arch ring 5 can be constructed by repeatedly using the short formwork for constructing the arch ring block.
can be constructed in parts, so the arch ring 5 can be constructed by a small number of people and in a fixed construction cycle, and since shorter formwork is used repeatedly, arch ring construction costs can be reduced.
Furthermore, since the arch center 1 is installed on the arch ring 5, the arch center 1 can be dismantled and removed easily and in a short time after the construction of the arch ring 5 is completed. It will be done.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and Fig. 1 is a schematic side view showing the state in which the arch center has been erected and the arch ring end blocks have been constructed, and Fig. 2 is a schematic side view showing the state in which the frame type shoring has been removed. Fig. 3 is a schematic side view showing the state in which the formwork moving support device is assembled and installed on the arch center; Fig. 3 is a schematic side view showing the state in which the central arch ring block is being constructed;
FIG. 4 is a schematic side view showing a state in which the construction of the arch ring is completed and the arch center is removed.
FIG. 5 is a side view showing the formwork moving support device installed at the arch ring block construction position, and FIG. 6 is a longitudinal sectional front view showing the arch ring block with concrete poured. Fig. 7 is a side view of the formwork moving support device, Fig. 8 is its vertical front view,
FIG. 9 is a side view showing the support structure for the upper end of the frame hanging material, FIG. 10 is a plan view thereof, FIG. 11 is a side view showing the support structure for the lower frame material in the formwork support frame and scaffolding, and FIG. The figure is its bottom view. In the figure, 1 is an arch center, 2 is a formwork movement support device, 3 is an arch ring block, 4 is an arch ring hanging material, 5 is an arch ring, 10 is a rail, 11 is a car body frame, 13 is a car body, and 14 is a mold Frame support frame, 20 is a frame hanging material, 21 is a hanging material insertion hole, 22 is a supporting metal fitting, 23 is a movable supporting metal fitting, 24 is a nut, 25 is a hanging material insertion hole, 26 is a supporting metal fitting, 27 is a movable supporting metal fitting, 28 is Natsu, 2
9 is a bottom formwork, 31 is a side formwork, 33 is a front end formwork, 37 is a scaffold, 38 is a climbing jack, 39 is a rail clamp, 40 is a manually operated lever traction machine, 41 is a chain, and 42 is a rail. Clamp, 44 is an abutment, 45 is an arch abutment,
48 is an arch center block, 52 is a column type support, 53 is a frame type support, 54 is a support beam,
55 is an arch ring end block, and 26 is a nut.

Claims (1)

[Claims] 1. An arch center 1 is assembled and erected in advance above the planned arch ring construction position, and the formwork for arch ring block construction is supported by the formwork moving support device 2 mounted on both sides of the arch center 1. The process of pouring concrete into the frame and constructing the arch ring block 3, and the process of moving the formwork, which has been removed from the mold after the concrete hardens, using the movable support device 2, are repeated, and the process of constructing the arch ring block 3 while the arch ring is being erected is repeated. The arch ring block 3 is supported by the arch center 1 via the arch ring hanging material 4, and after the arch ring 5 is completed, the arch ring hanging material 4 is removed and the arch center 1 is dismantled and removed. Arch ring construction method for concrete arch bridges.