JPH09203011A - Reconstruction work of short-span over-road bridge or overbridge into long-span bridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with temporary installation and removal of construction girders, and slow traveling of trains and reduce the construction period and cost, by driving foundation piles and erecting bridge piers at the outside of a rail way and laying construction girders made of hollow steel pipes as main bridge girders and thereafter, reinforcing the hollow steel pipes. SOLUTION: Foundation piles 7 are driven only at the outside of a railway. Receive girders 20 are laid under the railroad track above the foundation piles 7 so as to cross the rail way. Parapet girders 21 are arranged at the outside of the receive girders 20. Hollow precast members are reinforced by prestressed concrete (PC) steel materials to form the receive girders 20. The bridge piers 23 are constructed between the receive girders 20 and the parapet girders 21, and the foundation piles 7. Subsequently, exsisting bridge girders are removed and exchanged to hollow steel pipe girders 24 to put them between the receive girders. The girders 24 serve as construction girders temporarily. Temporary support points 3a are provided on existing abutments 3 and used as temporary bridge piers together with the receive girders 20. The girders 24 are reinforced with PC and used for the main bridge girders. Thereafter, the existing abutments are removed to widen the road width.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction method for reconstructing a short span overpass or overpass to a long span overpass or overpass, and particularly reinforced a hollow steel girder with prestressed concrete (PC) or reinforced concrete (RC). However, it relates to the construction method used for the main bridge girder.

[0002]

2. Description of the Related Art Conventionally, many iron girders which are lightweight and easy to construct are used for a railway bridge above a road in an embankment structure portion of a railway line. This iron girder is structurally noisy and has a narrow road, so the road width is narrow, which is one of the causes of traffic congestion. For this reason, the road width is widened by switching to a long span girder while passing the railway and road traffic. The construction procedure of this conventional construction method will be described with reference to FIGS. FIG. 1 is a diagram for explaining the procedure for constructing temporary earth retaining piles on both sides of the bridge. In FIG. 1 (a) (cross-sectional view), the bridge is a road 6 at the center of the road 6 and a road 6 It consists of an old bridge girder 2 supported on both sides by an old abutment 3, and a rail (RL) 1 is laid through this bridge girder. As shown in FIG. 1 (b) (plan view), in order to construct a new abutment, first, temporary earth retaining piles 5 are driven into the tracks on both sides of the aerial bridge at predetermined intervals at night when the train does not pass.

Next, as shown in FIG. 2, a temporary bridge abutment is provided on the track of the area where the temporary earth is retained so that the track 1 is not displaced, and a construction girder 9 is installed in this area. While excavating while supporting the beams 10 and so on, foundation piles 7 are carried out to construct a new abutment 8 made of reinforced concrete. next,
As shown in FIG. 3, the sandals 11 are installed on both sides of the old bridge pier 4, and a temporary support like a wedge is inserted between the sandals 11 and the old bridge girders 2 to temporarily receive the old bridge girders 2 with the sandals 11, and in this state The top of the old bridge pier 4 is destroyed, and then the temporary support material 12 is inserted between the old pier 4 and the old bridge girder 2 to remove the temporary support between the sandle 11 and the old bridge girder 2. FIG. 3 shows this state.

Next, as shown in FIG. 4, the sandle 11 is moved to the position of the old abutment 3 and the old bridge girder 2 is similarly received by the temporary reception, and the top portion of the old abutment 3 is broken to provide the sandle material 13. After constructing the construction girder 15 between the construction girder 9 and the old bridge girder 2 to reinforce the track, the sandle material 14 is installed between the temporary earth retaining pile 5 and the old abutment 3. In addition, in the construction procedure of FIGS. 3 and 4, the tops of the old pier 4 and the old abutment 3 are broken in order to match the main girder with a high girder height.

Next, as shown in FIG. 5, construction girders 9 and 1
5. Remove old bridge girder 2 and lay new bridge girder 16. At this time, since the back surface of the new abutment is backfilled, there is no problem even if the construction girder 9 is removed. In this state, the old pier 4, old abutment 3,
All temporary retaining piles inside the new abutment (road side) will be removed and the road width will be expanded. In addition, the temporary earth retaining piles on the outside of the new abutment will be removed or left as it is.

[0006]

As described above, conventionally,
It is common to install a new abutment while protecting the railroad track with a construction girder, lay the construction girder once, and then replace it with a new girder. I have to. A temporary abutment must be constructed to receive the work girder. In addition, since the work is on track, the train must slow down for a long time. The construction period is long because it requires night construction. As a result, construction costs are high. And so on. The present invention is for solving the above problems, in a reconstructing method for making a short span overpass or an overpass a long span, without the need for temporary installation or removal of the work girder, the train does not need slowing, construction The purpose is to shorten the period and reduce the construction cost.

[0007]

[Means for Solving the Problems] The method of reconstructing a long span span of a short span overpass or overpass of the present invention is to construct a foundation pile outside the track, then insert a girder into the roadbed, and then construct the foundation. A bridge girder will be installed between the pile and the girder. The girder has a structure reinforced with prestressed concrete, which eliminates the need for intermediate support piles in the track. This girder and old abutment are used as temporary bridge piers, and hollow steel girders are used as continuous girders between girders to temporarily serve as construction girders.
After that, after reinforcing the hollow steel girder with PC or RC, the old pier and old abutment are removed.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The construction procedure of the long span construction method of the present invention will be described below with reference to FIGS. FIG.
[Fig. 6] is a view showing a stage in which a foundation pile is applied. In the present invention, the foundation pile 7 is applied only outside the track. By enforcing it outside the track, construction can be done even while the train is running, and construction in the daytime is possible. Although the bridge pier is not shown in the center of the bridge girder in FIG. 6, the present invention is applicable to the case where the bridge pier is located in the center of the bridge girder and the case where the bridge pier is not provided.

Next, as shown in FIG. 7, the receiving girder 20 is installed under the track above the foundation pile 7 across the line. This construction is carried out by pushing the soil into the soil while removing the soil with an auger, and as shown in FIG. 8, the parapet girders 21 are similarly arranged on the outside of the receiving girder 20.

As shown in FIGS. 9 (a) and 9 (b), the receiving girder 20 is constructed as a double hollow steel pipe in which a PC steel material (wire) 22 is arranged, and then concrete is placed between the steel pipes. After the concrete is hardened, tension is introduced into PC steel to reinforce it. With this structure, the yield strength of concrete is dramatically increased, and it is possible to eliminate the need for intermediate support piles even if the length is increased. When the span of the receiving girder is short, after constructing the hollow steel pipe, concrete may be poured into the entire steel pipe to be reinforced with the PC steel material. Also,
As the receiving girder 20, as shown in FIGS. 9 (c) and 9 (d),
A structure in which a hollow precast member is reinforced with a PC steel material 22, or as shown in FIGS. 9 (e) and (f), a hollow precast block is pushed into the soil while removing the soil with an auger, and the blocks are sequentially connected. , PC steel 22
The structure may be reinforced by. Of course, the parapet girder 21 may also be reinforced similarly to the girder, and the girder and parapet girder may be integrally formed instead of being separate bodies.

Next, as shown in FIG.
A bridge pier 23 is installed between the parapet girder 21 and the foundation pile 7 so that the girder 20 and the parapet girder 21 can be received.

Thus, as shown in the plan view of FIG.
The foundation piles and bridge piers will be installed outside the track, and the girders and parapet girders will be passed between the piers, and there will be no intermediate support piles on the girders and parapet girders, and the construction will be completed without any work inside the track. be able to.

Next, as shown in FIG. 12, the old bridge girder 2 is removed and replaced with an erection girder 24 made of a hollow steel pipe to receive the girder 20.
Enforce in between. Since the erection girder 24 temporarily plays a role of a construction girder, it is easy to implement because it is lightweight, and it can be used as a temporary pier with the support girder 20 by providing a temporary fulcrum 3a on the old abutment 3. There is no need to implement a new temporary abutment.

As shown in FIG. 13, an erection girder (construction girder) 2
4 is provided with a PC cable 25. Concrete is cast in a steel pipe, and after hardening, a tension is applied to the PC cable to reinforce it, which is used as a main bridge girder. Since the PC cable has a parapet girder at the end of the work girder, it is necessary to apply tension on the lower side of the work girder as shown in FIG. The method of applying tension from the opposite end on the lower side (Fig. 14 (a)), the same method as in Fig. 14 (a), the end of applying tension is placed in the notch provided in the steel pipe. A method of providing the cable (Fig. 14 (b)), a method of taking out both ends of the PC cable from the lower side of the steel pipe, a method of making the ends outside the steel pipe (Fig. 14 (c)), a cutting provided at the ends of the steel pipe. The method (FIG. 14 (d)) to be provided in the notch is used. The bridge girder may have not only a structure reinforced with prestressed concrete but also a structure reinforced with reinforced concrete. Then, the old abutment is removed to widen the road width, and the construction according to the present invention is completed. In the above description, the application to the overpass has been described, but the present invention is not limited to this, and can be applied to the long span of the overpass in exactly the same manner.

[0015]

As described above, according to the present invention, foundation piles and bridge piers are implemented outside the track, and the receiving girder has a structure reinforced with PC. Further, this girder has a construction girder made of hollow steel pipe and an old abutment. Since it is reinforced with PC or RC after being applied as a temporary bridge pier, the following effects can be obtained.

Replace the old bridge girder with a construction girder and use PC or R
Since it is reinforced with C and used as it is for this bridge girder, the girder erection is only required once. Since the old abutment is used as a temporary pier, it is not necessary to construct a new temporary abutment. Since foundation piles and piers are constructed outside the tracks and there is no construction inside the tracks, it can be carried out while passing through the railway and roads. Since the bridge girder of the present invention is lightweight at the time of erection of the girder, the erection is easy. Since concrete is placed after erection of bridge girders, noise accompanying train running can be reduced. The enforcement cost is low. Since there is no construction on the track and daytime work is possible, the construction period can be shortened.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a procedure for constructing temporary retaining piles on both sides of a viaduct.

FIG. 2 is a diagram illustrating a procedure for constructing a construction girder and a new abutment.

FIG. 3 is a diagram illustrating temporary receipt by a sander.

FIG. 4 is a diagram illustrating a procedure for constructing a work girder.

FIG. 5 is a diagram illustrating a procedure for replacing an existing girder with a main girder.

FIG. 6 is an explanatory view of a foundation pile construction procedure in the present invention.

FIG. 7 is a diagram illustrating a procedure for constructing a receiving girder.

FIG. 8 is a diagram illustrating a procedure for constructing a parapet girder.

FIG. 9 is a diagram illustrating reinforcement by a PC cable.

FIG. 10 is a diagram illustrating the construction of a bridge pier.

FIG. 11 is a plan view illustrating a construction procedure of the present invention.

FIG. 12 is a diagram illustrating the construction of a construction girder.

FIG. 13 is an explanatory diagram in which the construction girder is the main bridge girder.

FIG. 14 is an example of a layout plan of a PC steel wire for making a construction girder a main bridge girder.

[Explanation of symbols]

1 ... RL, 2 ... Old bridge girder, 3 ... Old abutment, 3a ... Temporary fulcrum, 4
… Old piers, 5… Temporary retaining piles, 6… Roads, 7… Foundation piles, 8…
New abutment, 9 ... Construction girder, 10 ... Girder, 11 ... Sandle, 1
2 ... Temporary receiving material, 13 ... Sandle material, 20 ... Receiving girder, 21 ... Parapet girder, 22 ... PC steel material, 23 ... Bridge pier, 24 ... Erection girder (construction girder), 25 ... PC cable.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Fumihide Mito 1-6-5 Marunouchi, Chiyoda-ku, Tokyo Tohnichi Railway Co., Ltd.

Claims (5)

[Claims] 1. A short span overpass or overpass bridge in which foundation piles and bridge piers are constructed outside the track, bridge girders are passed between the bridge piers, and existing bridge girders are replaced with main bridge girders between the bridge girders. Is a reconstructing method for increasing the span, the main bridge girder is a short span overpass bridge, characterized in that after the construction girder made of hollow steel pipe is constructed, the hollow steel pipe is reinforced with prestressed concrete or reinforced concrete. Reconstruction method for spanning overpasses. 2. The method according to claim 1, wherein the receiving girder has a structure in which a hollow steel pipe is reinforced with prestressed concrete, and a method for reconstructing a long span of a short span overpass or overpass. 3. The method of claim 1, wherein the receiving girder has a structure in which a hollow precast member is reinforced by a PC steel material, and a method for reconstructing a long span of a short span overpass or an overpass bridge. . 4. The method according to claim 1, wherein the receiving girder has a structure in which a plurality of hollow precast blocks are joined together and reinforced with a PC steel material, and a long diameter of a short span overpass or an overpass bridge. Interchange and reconstruction method. 5. The method of claim 1, wherein parapet girders are arranged side by side on the outside of the receiving girder, for constructing a short span overpass or overpass with a long span.