JP2000110114A - Construction method for overhang-erected girder bridge using corrugated steel plate web and equipment for overhang erection work - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a construction method for cast-in-place overhang blocks for an overhang-erected girder of prestressed concrete construction using corrugated steel plate for web plate. SOLUTION: Stiffening frames 41, 42 restricting the deformation of a corrugated steel plate web are placed through a corrugated steel plate web 40 extended from an existing bridge body block 50, and the deadweight and work load of a concrete floor slab to be constructed are loaded to a corrugated steel plate web 40. Then, the upper and lower floor slab concrete is placed using a simple overhang erection equipment 10 and the bridge body is extended and erected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of constructing an overhanging block of an overhanging girder of a prestressed concrete structure using a corrugated steel plate as a web (web), and an overhanging work apparatus used therefor.

[0002]

2. Description of the Related Art A method of constructing a bridge of a prestressed concrete structure in which a bridge body is divided into 3 to 5 m in a bridge axis direction from a pier and alternately stretched to the left and right using a cantilever overhanging work device. Has been widely adopted. This overhanging construction method has features that a long span bridge can be easily constructed, and that the bridge can be bridged without being restricted by the space condition under the girder.

[0003] The construction process of the overhanging construction method using the conventional overhanging work apparatus is as follows. First, the removable rail is temporarily fixed on the existing bridge block. An overhanging work device is installed on the rail so that it can move forward and backward. The formwork and the scaffold of the bridge block to be constructed are suspended and supported from the overhanging work device to assemble the reinforcing bars and the like. The bridge block is constructed by placing concrete in the formwork and introducing prestress. Next, in preparation for the construction of the next block, the temporary fixing of the rail is released and the rail is advanced to the next block position. At this position, the rail is temporarily fixed again, and the rail is run on this rail to advance the overhanging work device to the construction position of the next block. The above steps are repeated to extend and build the bridge one after another.

[0004] The concrete bridge constructed in this manner has a large mass and is excellent in quietness.
It has features such as rust resistance. On the other hand, due to its large mass, it is necessary to strengthen the substructure such as piers in order to secure earthquake resistance, and there are problems such as economic efficiency.

[0005] From such a viewpoint, the characteristics of the overhanging girder bridge,
Taking advantage of its superiority, a new type of bridge has been developed and put into practical use by combining steel plate webs and concrete slabs to reduce weight. The features of the bridge with this new structure are different from the conventional steel girder bridge that simply combines steel plate and concrete.The corrugated steel plate that is bent so that the waveform repeats in the bridge axis direction is used as the web, and the upper and lower floor slabs are used. Is made of concrete to form a box-shaped cross-section girder.

FIG. 6 shows an example. Figure 6 shows overhanging girder bridge 1
A part of the side view of FIG. 00 shows a state in which the blocks are extended one block at a time from the pier 111 while using the conventional overhanging work device 120 to balance in the bridge axis direction left and right. For the pier 110, the overhanging erection has been completed, and the bridge abutment 112 is joined by cast-in-place concrete using a shoring, while the other awaits the bridge extending from the pier 111, and both bridges are in the center of the span. To complete a series of bridges.

FIGS. 7 and 8 are views of the upper and lower concrete floor slabs 131 and 13 taken along arrows DD and EE of FIG. 6, respectively.
2 shows a cross section of a box girder 130 connected by a web 133 of a corrugated steel plate.

[0008]

A concrete girder using a corrugated steel sheet as a web (web) has a large degree of freedom in deformation of the steel sheet. After the concrete on the upper and lower floor slabs harden, all the loads must be borne by the overhanging work equipment until the prestress is introduced. On the other hand, if the characteristics of the corrugated steel web, which is a structural member of another member, are fully utilized, it is not necessary to bear all the loads, such as its own weight and work load, to the overhanging work device as in the conventional case. The possibility of construction without using excessive equipment was studied.

That is, as a result of the research, the inventors can treat the corrugated steel plate in the bridge axis direction in a manner similar to a normal steel plate girder if the deformation is temporarily restrained when the new block is constructed. The present invention was completed by focusing attention. SUMMARY OF THE INVENTION The present invention provides a construction method and a construction method which reduce the burden on an overhanging work apparatus and satisfy appropriate and required specification requirements.

[0010] The applicant of the present invention has previously disclosed Japanese Patent Application No. 9-7181.
In the No. 5 application, in order to restrict the deformability of the corrugated steel sheet and control the deformation, it was proposed to mount a stiffening frame across the corrugated steel sheet. The technique was aimed at adjusting deformation such as deflection of a corrugated steel web. The present invention is an extension of this technology, in which the stiffening frame is made to be a member having higher mechanical strength, and the stiffening frame has an installation load supporting function when the stiffening frame is installed. As described above, an object of the present invention is to provide a lightweight and economical method of constructing an overhanging girder bridge and an apparatus therefor, making use of the advantages of the corrugated steel web.

[0011]

SUMMARY OF THE INVENTION In the construction of an overhanging girder bridge using a corrugated steel web, the present invention relates to a supplementary restraint for restraining the deformation of the corrugated steel web to the corrugated steel web extending from the existing bridge block. With the rigid frame interposed, the weight of the concrete floor slab of the new bridge block to be constructed and the working load are applied to the corrugated steel web, the upper and lower floor slabs are cast, and the bridge body is extended and erected. This is a method of constructing an overhanging girder bridge. The overhanging work device used for this is a long upper left and right vertical beam that protrudes forward, a bogie that mounts the base of the upper left and right vertical beam and runs on the existing block in the bridge axis direction, An overhanging work device comprising a horizontal beam extending from both sides by connecting beams, and having a portal-type structure in a front view, wherein a vertical and horizontal two-way overhead traveling crane is mounted on the vertical beam and the horizontal beam.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

This embodiment is an example in which the present invention is applied to an overhanging girder bridge having a prestressed concrete structure as shown in FIG. 6, but illustration of PC steel is omitted.

FIG. 1 is a side view of an overhanging work apparatus 10 according to an embodiment, in which a rail 5 temporarily fixed on an existing bridge block 50 is shown.
1 consists of a truck mounted via running wheels. The truck has a gate-shaped front main structure 12 and a rear main structure 13. The front main structure 12 and the rear main structure 13 are connected by a lower vertical beam 14, an upper vertical beam 20, and a breath 11.
Here, the vertical beam is a beam extending parallel to the bridge axis. The lower longitudinal beam 14 connects the front main structure 12 and the rear main structure 13, and a balance weight 15 is placed behind the rear main structure 13. The upper vertical beam 20 is connected to the tops of the front main structure 12 and the rear main structure 13 and protrudes longer than the front main structure 12. The upper longitudinal beam 20 is disposed at a position sufficiently high from above the bridge surface so that the corrugated steel sheet web 40 can pass thereunder. At the top end of the front main structure 12, a column 21 is erected, and diagonal members 22 and 23 are suspended from the top of the column 21 before and after the upper vertical beam 20.

A traveling crane 24 and a chain block 25 are mounted on the upper vertical beam 20 so that the corrugated steel web 40 or the like can be suspended and transported from the existing bridge block 50 to the front overhang position. Has become. The corrugated steel sheet web 40 is provided with strong stiffening frames 41 and 42 so that the corrugated steel sheet web 40 is connected to the existing bridge body block 50. Can be supported.

As shown in FIGS. 4 and 5, the corrugated steel web 40 is provided with two-stage stiffening truss frames 41 and 42,
A frame support beam 45, which is attached to both sides of the corrugated steel web 40 by frames 43, connecting bolts 44, etc., and supports a lower deck slab concrete form, is supported by a bracket 46. Although not shown, the receiving frame of the upper floor slab concrete formwork is supported by the stiffening truss frame 41 itself.

Accordingly, the corrugated steel sheet web 40 supports the own weight of the upper and lower concrete slabs, the weight of the formwork, etc. without being applied to the overhanging erection work device 10, so that the erection work device 10 according to the present invention It can be simplified compared to the device.

FIG. 2 is a view taken in the direction of arrows AA in FIG. 1, and the overhanging work apparatus 10 has a substantially portal-type structure. FIG. 3 is FIG.
FIG. A bidirectional overhead traveling crane 24 is suspended on the front and rear cross beams 30 and 31, an electric chain block 25 is suspended, and the corrugated steel sheet web supplied from behind the overhanging work apparatus 10 is taken in, suspended, and erected. It can be transported to a location. In addition, the lower horizontal beam 61 of FIG. 2 is suspended from the existing lower floor slab, and the lower horizontal beam 61 of FIG. Reference numeral 60 denotes a work platform.

FIG. 4 shows a corrugated steel web 4 of a new girder block.
0, two-stage stiffening truss frames 41 and 42 are attached at appropriate intervals to restrain the deformation of the waveform and secure the rigidity of the web alone, and furthermore, the left and right webs are provided at the front end. A connecting lateral stiffening beam 45 is provided to maintain web spacing and secure lateral rigidity.

FIG. 5 is a plan view of the stiffening truss frame 41 taken along the line CC in FIG. 4, in which a corrugated shape is secured by a separator that presses the valleys on both sides of the steel plate web 40. This stiffening truss frame 41 corresponds to a flange in a pseudo manner, increases the rigidity of the girder in the Y-axis, reduces the nature of the freedom of deformation of the corrugated steel plate, increases the X-axis cross-sectional performance, and increases the load of the upper and lower floor slab concrete. To be able to bear.

When the concrete reaches the predetermined strength, the prestress is introduced, the overhang work device is advanced, the corrugated steel plate of the next block is taken in, and the stiffening truss frame is mounted. Removal and installation are repeated, and the bridge is overhanging.

The structure and the mounting method of the stiffening truss frame of the above embodiment are merely examples, and if the rigidity in the Y-axis direction of the web of the corrugated steel sheet, which is the gist of the present invention, can be secured, Of course, it is not limited.

[0023]

According to the method and the apparatus of the present invention, a stiffening frame composed of a truss structure is interposed on both sides of a corrugated steel sheet web of a new block extending from an existing block to form a pseudo flange. The deformation of the corrugated steel sheet web can be temporarily restrained, and the weight of the slab and the working load for constructing the concrete slab can be borne by the corrugated steel sheet web. Therefore, the apparatus of the present invention does not need to bear all the loads unlike the conventional overhanging work apparatus, so that the apparatus can be of a lightweight and simple structure. As described above, it has become possible to provide an overhanging girder bridge using corrugated steel webs while taking advantage of the features and advantages of the overhanging construction method.

[Brief description of the drawings]

FIG. 1 is a side view of an overhanging work vehicle according to an embodiment.

FIG. 2 is a view taken along the line AA of FIG. 1;

FIG. 3 is a view taken in the direction of arrows BB in FIG. 1;

FIG. 4 is a side view showing a stiffening frame of a corrugated steel sheet web.

FIG. 5 is a plan view showing the stiffening frame of the corrugated steel sheet web (a view taken along the line CC in FIG. 4).

FIG. 6 is a construction explanatory view of an overhanging girder bridge.

FIG. 7 is a view as viewed in the direction of the arrow D-D in FIG. 6;

FIG. 8 is a view as viewed in the direction of arrows EE in FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Outrigger installation apparatus 11 Breath 12 Front main structure 13 Rear main structure 14 Lower vertical beam 15 Balance weight 20 Upper vertical beam 21 Support post 22 Diagonal member 23 Diagonal member 24 Traveling crane 25 Electric chain block 30, 31 Cross beam 40 Corrugated steel plate Web 41 Stiffening frame 42 Stiffening frame 43 Frame 44 Connecting bolt 45 Receiving beam 46 Bracket 50 Existing bridge block 51 Rail 100 Overhanging girder bridge 110 Bridge pier 111 Bridge pier 112 Abutment 120 (Conventional) overhanging work device 130 Box Girder 131 Upper concrete floor slab 132 Lower concrete floor slab 133 Web

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Shouichi Ino 3-4-1 Marunouchi, Chiyoda-ku, Tokyo PS Co., Ltd. (72) Inventor Masahiro Furushiro 408 Kawato-cho, Chuo-ku, Chiba Co., Ltd. F-term in Higashiha Works (reference) 2D059 AA14 CC04 CC06 DD03 DD09

Claims (2)

[Claims] In the construction of an overhanging girder bridge using a corrugated steel web, a stiffening frame for restraining deformation of the corrugated steel web is interposed on a corrugated steel web extending from an existing bridge body block, A method for constructing an overhanging girder bridge, comprising applying the own weight and working load of a concrete slab to be built to the corrugated steel web, placing concrete on the upper and lower slabs, and extending the bridge body. 2. A long upper left and right vertical beam extending forward, a bogie on which a base of the upper left and right vertical beam is placed and runs on an existing block in a bridge axis direction, and the upper vertical beam is connected. An overhanging work device comprising a horizontal beam extending from both sides and having a portal-type structure as viewed from the front, wherein a vertical and horizontal two-way overhead traveling crane is mounted on the vertical beam and the horizontal beam.