JPH0454037B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is a railway construction using a precast concrete roof girder (hereinafter referred to as a PC roof girder), an upper steel box girder, and a lower steel box girder. This relates to an under-roadbed crossing structure that is constructed to cross under railroad tracks or under roads.

[Conventional technology]

Conventionally, as a cross-sectional structure under the roadbed, (1) Japanese Patent Application Publication No. 1983
-4 as published by Publication No. 91534.
After penetrating into the ground a steel corner horizontal pipe with a square cross section, a large number of ceiling middle steel horizontal pipes with a square cross section, and a large number of steel horizontal pipes for the side wall middle part with a square cross section, each horizontal pipe is A large number of window holes are formed by fusing or the like to face each other in the joint side plates of the intermediate section, and a large number of reinforcing members extending in the width direction of the side plates are welded to the inner surface of the joint side plates of each intermediate steel horizontal pipe. A number of reinforcing members extending in the width direction of the side plates are fixed by welding to the inner surface of the side plate of the non-joint part of each intermediate horizontal steel pipe, and furthermore, a number of reinforcing members extending in the width direction of the side plate are fixed to the inner surface of the side plate of the non-joint part of each horizontal steel pipe for the intermediate part. A steel peripheral reinforcing plate is placed and fixed by welding, and then a large number of vertical reinforcing bars extending in the longitudinal direction of the tube are placed in each corner horizontal pipe and each intermediate steel horizontal pipe, and each corner A cross-section structure under the roadbed is known in which connecting reinforcing bars extending in a direction perpendicular to the longitudinal direction of the pipe are arranged across the horizontal pipe and each intermediate steel horizontal pipe, and then each horizontal pipe is filled with concrete. There is. (2) As shown in FIGS. 1 and 2, a large number of PC roof girders 1 on the ceiling and support girders 5 supporting both ends of the PC roof girders 1 are integrated by tightening the PC steel members 7, Both ends of the large number of PC roof girders 2 on the side wall are supported by the abutment 6, and the lower end PC
Roof girder 2 and abutment 6 are concrete slab 14
Under-subgrade crossing structures supported by sub-grades are also known.

[Problem to be solved by the invention]

In the case of the above-mentioned (1) below-roadbed crossing structure, the structure is extremely complex, the amount of steel used is large, and it is necessary to perform fusing and welding at many locations, so the construction period is long and the construction cost is high. The problem is that it gets expensive.

In addition, in the case of the above-mentioned (2) below-roadbed crossing structure, the PC
The roof girders are not rigidly connected in the lateral direction, and the gaps between adjacent PC roof girders are only filled with mortar, resulting in a structure that cannot resist bending in the lateral direction. Therefore, PC
A cross-sectional force whose span is the entire length of the PC roof girder will act on the roof girder, and accordingly,
As the cross section of the PC roof girder becomes larger, construction machinery with greater capacity is required. In addition, when the track is double-track or more, and the length of crossing under the track is long, the cross section of the PC roof girder is too large for conventional construction methods, and there is no construction machine that has the ability to push it. There may be cases where construction is impossible even if there are no problems.

Furthermore, in the case of the above-mentioned (2) below-roadbed crossing structure, similar PC roof girders are used at the corners of the PC roof girders on the side walls and the PC roof girders on the ceiling.
There is no working space to tighten the horizontally tightened PC steel materials that integrate the roof girders, making it impossible to integrate the PC roof girders in the lateral direction.

[Purpose and structure of the invention]

The purpose of this invention is to provide an under-roadbed crossing structure that eliminates the above-mentioned drawbacks,
The gist of the present invention is to provide an under-base course crossing structure consisting of a plurality of PC roof girders 1 on the ceiling part and a plurality of PC roof girders 2 on the side wall parts, which are press-fitted across the sub-base ground. Hollow upper steel box girders 3 are press-fitted adjacent to the PC roof girders 1 on both the left and right sides of the section, and each PC roof girder 1 and the upper steel box girders 3 on both the left and right sides extend in the left and right direction. Numerous horizontal clamps spaced along the length of the girder
They are integrated by tightening the PC steel materials 4, and a lower steel box girder 8 is press-fitted into the lower part of the side wall adjacent to the PC roof girder 2, and each PC roof girder 2, the upper steel box girder 3 and the lower steel box girder The box girder 8 is integrated by tightening a large number of horizontally tightened PC steel members 10 that extend in the vertical direction and are arranged at intervals in the longitudinal direction of the girder, and is cast between the left and right lower steel box girders 8. The concrete deck slab 14 is connected to the concrete deck slab 14 by the PC steel material 13 buried in the concrete deck slab 14, and after tightening the horizontally tightened PC steel materials 4 and 10, the upper steel box girder 3
This under-roadbed crossing structure is characterized in that the inner and lower steel box girders 8 are filled with hardenable material 18 such as concrete or mortar.

〔Example〕

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

3 to 6 show a first embodiment of the present invention, in which FIG. 3 is a cross-sectional view of the under-roadbed crossing structure, and FIG. 4 is a cross-sectional view taken along the line B-B in FIG. 3. , Figure 5 is a plan view showing the arrangement of horizontally tightened PC steel materials,
Figure 6 shows the upper steel box girder, ceiling and side walls.
FIG. 3 is a cross-sectional view showing a horizontal tightening fixing portion with a PC roof girder.

The ceiling part is composed of a plurality of PC roof girders 1 extending in the front-rear direction and upper steel box girders 3 placed adjacent to the sides of the PC roof girders 1 at both left and right ends,
The left and right side walls are composed of a plurality of PC roof girders 2 located below the upper steel box girder 3 and a lower steel box girder 8 located at the lowest stage, and each of the PC
The roof girders 1, 2 are provided with cylindrical hollow portions 1C, 2C extending through them in the longitudinal direction.

At the top and bottom of the cross section of each PC roof girder 1 in the ceiling, horizontal tightening holes 9 for penetrating the horizontal tightening PC steel material 4 necessary for integrating the PC roof girders 1 are provided at intervals in the longitudinal direction of the girder. lateral fasteners are provided on the inner wall side and outer wall side of the cross section of each PC roof girder 2 in the side wall portion to penetrate the transverse fastening PC steel material 10 necessary for integrating the PC roof girders 2 together. Holes 11 are provided at intervals in the longitudinal direction of the girder.

Further, the upper steel box girder 3 is also provided with horizontal tightening holes for penetrating the horizontal tightening PC steel materials 4 and 10 necessary for integration with the respective PC roof girders 1 and 2,
In addition, the lower steel box girder 8 is also provided with horizontal tightening PC steel materials 10 necessary for integration with the PC roof girder 2.
A horizontal tightening hole and its fixing portion are provided for penetrating the steel box girder, and a rigid reinforcing steel rib 12 for use as the main body structure of the structure is fixed by welding inside each steel box girder.

The upper steel box girders 3 on both left and right sides of the ceiling and all the PC roof girders 1 between them are a large number of horizontally tightened PCs extending in the left and right direction and arranged at intervals in the longitudinal direction of the girders. The upper steel box girder 3, the lower steel box girder 8, and all the PC roof girders 2 between them extend in the vertical direction and are spaced apart from each other in the longitudinal direction of the girder. It is tightened by a large number of horizontally tightened PC steel members 10 arranged, and each PC roof girder and steel box girder are integrated.

Concrete is poured between the left and right lower steel box girders 8 to form a concrete deck slab 14, and the PC steel materials 13 inserted through the side plates of each lower steel box girder 8 are buried in the concrete deck slab 14. The concrete floor slab 14 is integrally connected to the lower steel box girder 8, and after the horizontal tightening PC steel members 4 and 10 are tightened,
The upper steel box girder 3 and the lower steel box girder 8 are filled with hardenable material 18 such as concrete or mortar.

As the horizontal tightening PC steel materials 4 and 10, for example, unbonded PC steel strands are used in order to facilitate construction since the interiors of the steel box girders 3 and 8 are used as work spaces.

In Figures 3 to 6, 5' is a concrete decorative girder, 6' is a concrete decorative pillar,
15 is an anchor plate, 16 is a fixing device, and 17 is a filler material.

Next, the construction order in constructing the under-roadbed crossing structure of the first embodiment will be explained.

After the preparation work for pushing in the PC roof girders is completed, the propulsion machine is set and the PC roof girders 1 on the ceiling are first press-fitted one by one. Next, the upper steel box girders 3 at the left and right corners between the ceiling and the side walls are press-fitted, followed by the PC roof girders 2 and the lower steel box girders 8 at the left and right side walls. Complete the work.

Next, remove the earth and sand stuck in the joints between the PC roof girders and between the PC roof girders and the steel box girders using jet water, etc.

Next, a worker enters the steel box girder and inserts the horizontally tightened PC steel materials 4 and 10 for the ceiling and side walls.
A hardening filler 17 such as mortar is filled between the PC roof girders and between the PC roof girders and the steel box girders. After the filler 17 reaches a predetermined strength, the anchor plate 15 and fixing device 16 are set at the ends of the horizontally tightened PC steel materials 4 and 10, and the PC steel material 4 in the ceiling section is first tensioned and fixed. Next, the horizontally tightened PC steel members 10 on the left and right side walls are tightened and fixed.

After completing the tension fixing of all horizontally tightened PC steel materials,
Each PC roof girder 1 on the ceiling, each PC roof girder 2 on the left and right side walls, and the lower left and right steel box girders 8
The entire section surrounded by is excavated, and then concrete is poured between the left and right lower steel box girders 8 to form the concrete slab 14. At this time, for rigidly connecting the concrete slab 14 and the lower steel box girder 8,
The PC steel material 13 is inserted into the through hole in the side plate of the lower steel box girder 8 and embedded in the concrete slab 14.

After the bottom slab concrete has hardened, a worker enters the lower steel box girder 8 and tensions the PC steel members 13 to integrate the lower steel box girder 8 and the concrete deck 14, and then each steel box girder 3, 8 are filled with hardening material 18 such as concrete or mortar, and finally, each PC roof girder 1, 2 and each steel box girder 3,
A decorative beam 5' and a decorative pillar 6' are constructed so as to wrap around both ends of the decorative beam 5' and the decorative column 6'.

When carrying out this invention, if the cross section of the steel box girder is so small that it is impossible for a worker to enter it and place or tension the horizontally tightened PC steel members, the method shown in Fig. 7 may be used. As in the second embodiment, a similar steel box girder 3' is press-fitted into the lower part of the upper steel box girder 3 that lines up with the PC roof girder 1 in the ceiling, and these steel box girders 3, 3' A large working space may be secured by gas-cutting a part of the joint.

If the PC roof girder and steel box girder are too long to be transported, they will be fabricated in several blocks, and the structure will be such that the blocks can be rigidly connected at the construction site.

8 and 9 show an example of a rigid structure of PC roof girder blocks, in which a plurality of anchor bolts 19 are embedded in the end faces of PC roof girder blocks 1A, 1B and 2A, 2B, and each
A joint fitting 20 is interposed between the ends of the PC roof girder blocks, and each PC roof girder block and the joint fitting 2
0 is rigidly connected to the anchor bolt 19 and a nut 21 screwed thereto.

Figures 10 and 11 show an example of a rigid structure of steel box girder blocks, in which steel joint tubes made of square tubes are attached to the ends of one of the steel box girder blocks 3A and 8A. One side of the joint tube 22 is fitted and fixed by welding, and the other side of the joint tube 22 is fitted into the end of the other steel box girder block 3B, 8B and connected by a plurality of bolts and nuts 23. .

In addition, in order to facilitate the insertion and placement of the horizontally tightened PC steel material 4, as shown in Fig. 12, the horizontally tightened holes of the PC roof girder 1 at both left and right ends of the ceiling are made curved, and the horizontally tightened PC steel material is Both ends of 4 may be curved, and the side walls may be tightened laterally.
The PC steel material 10 may also be curved at both end portions as described above.

〔Effect of the invention〕

According to this invention, in an under-base course crossing structure consisting of a plurality of PC roof girders 1 on the ceiling part and a plurality of PC roof girders 2 on the side wall parts, which are press-fitted across the sub-base ground, the left and right sides of the ceiling part are Hollow upper steel box girders 3 are press-fitted on both sides adjacent to the PC roof girders 1, and the upper steel box girders 3 on both left and right sides of each PC roof girder 1 extend in the left-right direction and extend in the girder longitudinal direction. It is integrated by tightening a large number of horizontally tightened PC steel members 4 arranged at intervals, and a lower steel box girder 8 is press-fitted into the lower part of the side wall adjacent to the PC roof girder 2, and each
The PC roof girder 2, the upper steel box girder 3, and the lower steel box girder 8 are integrated by tightening a large number of horizontally tightened PC steel members 10 that extend in the vertical direction and are arranged at intervals in the longitudinal direction of the girder. The left and right lower steel box girders 8 and the concrete slab 1 placed between them
4 is a PC buried in concrete slab 14
It is connected by a steel material 13, and the horizontally tightened PC steel material 4,
10, the upper steel box girder 3 and the lower steel box girder 8 are filled with hardening material 18 such as concrete or mortar, so that the PC roof girders 1 and The upper steel box girder 3, the side wall PC roof girder 2, the upper steel box girder 3, the lower steel box girder 8, and the concrete integrally connected to the lower steel box girder 8. A strong under-roadbed crossing structure consisting of the floor slab 14 can be constructed easily, quickly, and at low cost by simple means.

In addition, the stress in the direction perpendicular to the extension direction of the PC roof girder 1, that is, the short span direction of the ceiling, is
Since the stress is transmitted to the roof girder 1 and the stress is transmitted to the foundation via the side walls, the cross section of the PC roof girder can be made small.Furthermore, the stress in the ceiling section is mainly transmitted to the foundation via the side walls, so the stress of the PC roof girder is transmitted to the foundation through the side walls. The length can be extended, so even if the transverse length of the subgrade is long, a cross-section structure under the subbase can be constructed without increasing the cross section of the PC roof girder 1, and the load acting on the ceiling can be reduced. can be distributed to the side wall, which means that what used to be a support girder in a prestressed concrete structure can be
It is also possible to change to a decorative girder with a reinforced concrete structure, which is cheaper, and for the same reason, it is also possible to omit the PC steel material used to rigidly connect the PC roof girder and support girder. The box girder is
Not only does it secure work space, but it also serves as a structural member of the structure itself, making it possible to construct an inexpensive under-roadbed crossing structure.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of a conventional cross-sectional structure under the roadbed.
FIG. 2 is a sectional view taken along line A--A in FIG. 1. 3 to 6 show a first embodiment of the present invention, in which FIG. 3 is a cross-sectional view of the under-roadbed crossing structure, and FIG. 4 is a cross-sectional view taken along the line B-B in FIG. 3. , Figure 5 is a plan view showing the arrangement of the horizontally tightened PC steel materials, and Figure 6 is a cross-sectional view showing the horizontally tightened rigid connection between the upper steel box girder and the PC roof girders in the ceiling and side walls. . FIG. 7 is a cross-sectional view showing a corner of an under-roadbed crossing structure according to a second embodiment of the present invention. Figure 8 is a PC
9 is a sectional view taken along the line C-C of FIG. 8, FIG. 10 is a vertical sectional side view showing the joint of the steel box girder block, and FIG. The sectional view taken along line D-D in the figure, Figure 12 is horizontal tightening.
FIG. 7 is a plan view showing another example of arrangement of PC steel materials. In the figure, 1 and 2 are precast concrete roof girders (PC roof girders), 3 is an upper steel box girder, 4 is a PC steel material, 5' is a decorative girder, 6' is a decorative column,
8 is the lower steel box girder, 9 is the horizontal tightening hole, 10 is the PC steel material, 11 is the horizontal tightening hole, 13 is the PC steel material, 14 is the concrete slab, 16 is the anchor, 17 is the filler,
18 is a hardening material, 19 is an anchor bolt, 20
2 is a joint fitting, and 22 is a steel joint tube.

Claims (1)

[Claims] 1 Multiple precast concrete roof girders in the ceiling section press-fitted across the roadbed subgrade 1
In an under-roadbed crossing structure consisting of a plurality of precast concrete roof girders 2 on the side walls, hollow upper steel box girders 3 are press-fitted adjacent to the precast concrete roof girders 1 on both left and right sides of the ceiling. , each precast concrete roof girder 1 and the upper steel box girder 3 on both the left and right sides are integrated by tightening a large number of horizontally tightened PC steel members 4 that extend in the left and right direction and are arranged at intervals in the longitudinal direction of the girder. Then, a lower steel box girder 8 is press-fitted into the lower part of the side wall adjacent to the precast concrete roof girder 2, and each precast concrete roof girder 2 is connected to the upper steel box girder 3 and the lower steel box girder 8. is integrated by tightening a large number of horizontally tightened PC steel members 10 extending in the vertical direction and arranged at intervals in the longitudinal direction of the girder,
The left and right lower steel box girders 8 and the concrete slab 14 cast between them are connected by the prestressing steel members 13 buried in the concrete slab 14, and after tightening the horizontally tightened prestressing steel members 4 and 10, the upper part A cross-sectional structure under a roadbed characterized in that a hardening material 18 such as concrete or mortar is filled in the steel box girder 3 and the lower steel box girder 8.