JP3141741B2 - Continuous bridge construction method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous bridge construction method for continuously integrating existing bridges having a hinged rigid frame structure.

[0002]

2. Description of the Related Art There are many construction examples of a conventional multi-span bridge type in which a hinged rigid frame type is used due to conditions such as economy and simplification of structural design. The structure of this type of existing bridge is
As shown in FIG. 7, a bridge girder 2 extending from the left and right of the upper part of the pier 1 is formed as one unit, and the bridge girder 2 of the other unit extending from the opposite side at the center of the span is connected to the hinge girder 3. Connected.

[0003] However, in the existing bridge of this type of structure, the following problems have become apparent due to the assumed creep at the time of construction and differences in traffic conditions.

[0004]

[Problems to be solved by the invention]

(1) The bridge girders relatively oscillate due to the recent increase in the traffic load of the traffic vehicles, and this movement wears out the central hinge support and the telescopic device. It is time-consuming and expensive to maintain. (2) Since the deformation due to creep considered at the time of construction was actually large, deformation such as drooping of the center hinge support has become a problem. (3) When used for traffic in such a hanging state,
There is a possibility that the members may crack due to the influence of the repeated load of the traffic vehicle or the like, which may cause breakage. (4) Further, the unevenness due to the drooping has a bad influence on the traveling performance of the traffic vehicle.

[0005] The present invention provides a continuous bridge construction method in which individual bridge girders of an existing bridge are integrally connected to each other to increase the strength of members and to prevent vibration between joints between the bridge girders. It is intended to be.

[0006]

In order to achieve the above object, according to the first aspect of the present invention, there is provided a space between bridge girders in an existing box girder type bridge having a hinged rigid frame structure. Fixing blocks are fixed on both sides in both box girders with the part interposed therebetween, and a PC steel material is arranged between the fixing blocks, and the bridge girders are connected by tension fixing.
The strength of the member is enhanced by prestressing the C steel.

In the invention according to the second aspect of the present invention, the function of the hinge support is stopped after the hinge support or the telescopic device is buried or removed by shortening the play portion. To fill the gap between both bridge girders and to integrate them.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a method for connecting existing box girder bridges according to the present invention. 1 and 2 are a side sectional view and a plan sectional view of a box girder type bridge according to the present invention.

The existing bridge 10 shown in the figure has an internally hollow box girder 14 extending on both sides of an upper part of a pier 12 and an overhang 16 integrated in the width direction on the upper part of the box girder 14. For use on the road surface, box girder 1
Numeral 4 has an arch shape having a maximum height at a junction with the pier 12 and a minimum height at a junction with the opposing box girder 14.

The junction between the two box girders 14 has a gap d as shown in FIG. 3 and FIG. 4 in an enlarged manner. Hinge supports 20 are provided on the right and left sides surrounded by the partition wall 18 so as to be engaged with each other.

In the integration work of this type of existing bridge, first, a pair of fixing blocks 22 and 24 are respectively installed on the left and right sides of both box girders 14 at symmetrical positions with the gap d therebetween. One fixing block 22 pair is installed at a position close to the pier 12, and the other fixing block 24 is
4 from the center of the partition wall 26 provided in this portion
Is placed in contact with

Each of the fixing blocks 22 and 24 has a structure shown in FIGS.
As shown in the enlarged view of FIG.
0 and 32 are opened in three columns. In the lower part of the fixing block 24, three rows of holes 32a for inserting the PC steel material 28 supplied from the fixing block 22 side are formed.

Next, the lower floor of each of the partition walls 18 and 26 is drilled to form a hole 34 for inserting a PC steel material. As shown in FIG. 4, the lower floor of the partition wall 18 has a total of six holes 34 on one side.
Are opened in parallel.

Prior to the wiring and fastening work of the PC steel material 28, the play portion d is filled with a filling material such as ultra-high-strength concrete C as shown in FIG. With 20 buried or removed,
Both box girders 14 are integrated.

Of course, this filling work is simultaneously performed on the road surface or the overhang portion 16, and the road surface can be used for traffic soon after the construction.

If a sheath tube for inserting the PC steel material 28 is arranged at the time of filling, the insertion work of the PC steel material 28 does not become an obstacle. By filling the super-high-strength concrete, rainwater does not enter the inside of the box girder 14, which is preferable from the viewpoint of rust prevention of the PC steel material 28.

Next, the PC steel material 28 is applied to each of the partition walls 18, 26.
The lower floor portion is passed between the fixing blocks 22 and 24 of the opposing box girder 14 through an insertion hole 34 penetrated in parallel with the fixing blocks 22 and 24, as shown in FIGS.
By fastening the rear protruding end of 4 with a nut 36,
A prestress is introduced between the two box girders 14 with a predetermined tension.

As described above, a pair of fixing blocks 22 and 24 are installed in both box girders 14, and holes 34 for PC steel material insertion are formed in the lower floors of the partition walls 18 and 26, and the clearance d is formed. After filling with the filling material, the PC steel material 28 is disposed between the fixing blocks 22 and 24, and a prestress is introduced into the PC steel material 28 while receiving a reaction force by the fixing block.
The bridge girders are integrally connected, and the prestress serves as a resistance to a positive bending moment at the center of the span between the two box girders 14.

In the above embodiment, the present invention is carried out inside the box girder. This is because the use of the internal space of the box girder allows the improvement work to be performed without providing an external support. This is because the rust prevention measures described above are necessary.

[0020]

As described in detail in the above embodiments, the present invention according to claim 1 has a P
By connecting the bridge girders with C steel, it can be integrated into a state where the strength of the members is enhanced by the pre-stress of PC steel, the strength of the existing bridge with hinged ramen structure can be improved, and the hinge bearings droop This also improves the traveling performance of the vehicle. In addition, the workability is good because it is not accompanied by the work of increasing the wall thickness such as concrete overstrike.

Further, in the invention according to the second aspect of the present invention, since the bridge girders are integrated with the central hinge supporting portion being buried, the removing work of the hinge supporting portion is performed in the improvement work. is not required, in addition to workability becomes good, especially in the bridges box girder system, without rainwater into the hollow interior intrusion, the advantages of such a preferable also from the top of the anti-corrosion of PC steel is there.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing an overall configuration of an embodiment of the present invention.

FIG. 2 is a plan sectional view of the same.

FIG. 3 is an enlarged view of a portion A in FIG. 1;

FIG. 4 is a sectional view taken along line BB of FIG. 3;

FIG. 5 is an enlarged view of a portion C in FIG. 1;

FIG. 6 is an enlarged view of a part D in FIG. 1;

FIG. 7 is an explanatory view showing a general configuration of a conventional bridge having a hinged ramen structure.

[Explanation of symbols]

 10 Existing bridge 12 Pier 14 Box girder 22, 24 Anchoring block 28 PC steel C Filled concrete

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) E01D 21/00 E01D 19/12

Claims (2)

(57) [Claims] 1. An existing box girder having a hinged rigid frame structure.
In both box girders across the gap between bridge girders
The fixing block is fixed on both sides of, P between the fixing block
A continuous bridge construction method characterized by arranging C steel materials and fixing them in tension. 2. The continuous bridge construction method according to claim 1, wherein the play portion is thinned.