JP2004116060A - Erection method for corrugated steel plate web bridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance the junction strength of a corrugated steel plate and a subfloor slab to obtain a sufficient durability in the erection method for a corrugated steel plate web bridge making use of a corrugated steel plate. <P>SOLUTION: A pair of corrugated steel plates constituting a block B(n+1) next to the head block B(n) are previously erected in the condition that a hanging support structure 100 for constructing a subfloor slab is suspended from a pair of corrugated steel plates 16 constituting the head block B(n) of an unexecuted upper floor slab. In this time, a precast corrugated steel plate 18 in which concrete blocks 32 constituting a part of the subfloor slabs 14 is embedded and jointed in the lower end is used as each corrugated steel plate 16 used for the previous erection. In this way, deterioration fear of unification due to bubbles or generation of bleeding resulting from placing concrete jointed under existing concrete members into the under face of the lower end flange of the corrugated steel plate like the conventional cases is eliminated. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method of erection of a corrugated steel web bridge for each block of a predetermined length by overhanging construction.
[0002]
[Prior art]
The corrugated steel sheet web bridge is configured to extend in the bridge axis direction so as to form a box-shaped cross section with the upper deck, the lower deck, and a plurality of corrugated steel sheets connecting them, The erection is generally performed for each block of a predetermined length by overhanging construction.
[0003]
At that time, an erection method using a corrugated steel plate is also adopted (for example, see “Non-Patent Document 1”). In this erection method, a plurality of corrugated steel sheets constituting a block next to the top block are suspended in a state in which a suspension support for the construction of the bottom slab is suspended on a plurality of corrugated steel sheets constituting the top block without the top slab. After the steel plates are erected in advance, the suspension supports are moved to these erected steel plates, and in this state, the construction of the lower slab constituting the next block and the construction of the upper slab constituting the head block are performed. It has become.
[0004]
[Non-patent document 1]
"Prestressed Concrete", Japan Prestressed Concrete Technology Association, Vol. 44, No. 1, January 31, 2002, p. 55
−57
[Problems to be solved by the invention]
The construction efficiency can be improved by constructing the upper slab and the lower slab in parallel in separate blocks as described above, but the construction of the upper slab and the lower slab itself is performed by cast-in-place using a formwork. It is done in.
[0005]
At that time, there are the following problems regarding the construction of the lower deck.
[0006]
That is, the corrugated steel sheet generally has a configuration in which flanges are joined to both upper and lower ends of a corrugated steel sheet main body, and the joining with the lower floor slab is performed by angled dowel joining. However, in such a joint structure, since concrete is cast on the lower surface of the lower end flange portion of the corrugated steel plate in reverse, the workability is extremely poor, and there is a concern that the integration may be deteriorated due to generation of bubbles and breathing. You. For this reason, it becomes difficult to increase the bonding strength between the corrugated steel sheet and the lower slab, and there is a problem that it is difficult to secure sufficient durability.
[0007]
The present invention has been made in view of such circumstances, and in a method of erection of a corrugated steel sheet web bridge using a corrugated steel sheet, sufficient durability is improved by increasing the joining strength between the corrugated steel sheet and the lower slab. It is an object of the present invention to provide a method of erection of a corrugated steel web bridge that can be secured.
[0008]
[Means for Solving the Problems]
The present invention is intended to achieve the above object by devising the configuration of the corrugated steel sheet when the corrugated steel sheet is erected in advance.
[0009]
That is, the method of erection of the corrugated steel web bridge according to the present invention is as follows.
In a method of erection of a corrugated steel sheet web bridge extending in the bridge axis direction so as to form a box-shaped cross section with an upper slab, a lower slab, and a plurality of corrugated steel sheets connecting them, by overhanging construction for each block of a predetermined length. ,
A plurality of corrugated steel sheets constituting the block next to the above-mentioned top block were erected in advance in a state in which the suspension support for the lower deck slab was suspended on the plurality of corrugated steel sheets constituting the top block without the upper slab. After that, the suspension support is moved to these pre-installed corrugated steel plates, and in this state, the construction of the lower slab constituting the next block and the construction of the upper slab constituting the top block are performed. Is composed of
Each of the corrugated steel sheets used for the preceding erection is configured to use a precast corrugated steel sheet in which a concrete block constituting a part of the lower floor slab is embedded and joined at a lower end portion of the corrugated steel sheet. Is what you do.
[0010]
The above-mentioned "precast corrugated steel sheet" refers to the shape of the lower end of the corrugated steel sheet or the size and shape of the concrete block, as long as the concrete block constituting a part of the lower slab is embedded and joined to the lower end of the corrugated steel sheet. Is not particularly limited.
[0011]
Operation and Effect of the Invention
As shown in the above configuration, the method of erection of the corrugated steel sheet web bridge according to the invention of the present application is a method in which a plurality of corrugated steel sheets constituting the top block without the upper slab are suspended with the suspension support for the lower slab. Then, after a plurality of corrugated steel plates constituting the block next to the first block are erected in advance, the suspension supports are moved to these erected corrugated steel plates, and in this state, the lower floor slab constituting the next block is formed. Since the construction and the construction of the top floor slab constituting the top block are performed, the upper slab and the lower slab can be constructed in parallel in separate blocks, thereby increasing construction efficiency. . In addition, the use of the suspension shoring enables the construction of the lower slab to be performed to some extent efficiently.
[0012]
In particular, in the present invention, as each corrugated steel sheet used for the preliminary erection, a precast corrugated steel sheet in which a concrete block constituting a part of the lower floor slab is embedded and joined at the lower end thereof is used as in the related art. Therefore, it is not necessary to cast concrete on the lower surface of the lower flange portion of the corrugated steel plate. For this reason, unlike the related art, there is no concern about a decrease in integration due to the occurrence of bubbles or breathing due to reverse hitting, thereby increasing the bonding strength between the corrugated steel sheet and the lower slab.
[0013]
As described above, according to the invention of the present application, in the method of erection of the corrugated steel sheet web bridge using the corrugated steel sheet, it is possible to increase the bonding strength between the corrugated steel sheet and the lower slab to ensure sufficient durability.
[0014]
Moreover, in the present invention, the adoption of the precast corrugated steel sheet makes it possible to eliminate the lower end flange portion and the angle dowel of the corrugated steel sheet, so that the manufacturing cost of the corrugated steel sheet can be reduced, thereby reducing the construction cost. be able to.
[0015]
Further, in the present invention, since the portion where the reinforcing bars near the joint with the corrugated steel plate in the lower floor slab are dense is precast, the on-site work can be reduced, thereby shortening the construction period. .
[0016]
In the above configuration, the construction of the upper floor slab, the plurality of precast ribs were bridged between the upper ends of the plurality of corrugated steel plates at predetermined intervals in the bridge axis direction, and a plurality of precast plates were laid on these precast ribs. Later, if these precast ribs and precast plates are used as a formwork to cast concrete on the upper slab, it will be possible to construct a support from the lower slab and to erection from the overhanging slab part as before. The construction of the upper floor slab can be easily performed as compared with the case where the construction of the upper floor slab is performed by extending the beams for use. Thus, the construction can be simplified not only for the construction of the lower slab but also for the construction of the upper slab.
[0017]
In this case, the specific shape and number of the “precast ribs” are particularly limited as long as the “precast ribs” are configured so as to be able to span between the upper end portions of the plurality of corrugated steel plates. Not something.
[0018]
In addition, the above-mentioned “precast plate” has a specific shape as long as the form can be formed by laying the precast plate on the precast ribs to form a formwork for placing concrete on the upper floor slab. There is no particular limitation on the number of laying or the like.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0020]
FIG. 1 is a perspective view showing a state in which a corrugated steel web bridge 10 to which an erection method according to an embodiment of the present invention is applied is being erected.
[0021]
As shown in the figure, the corrugated steel web bridge 10 extends in the bridge axis direction so as to form a box-shaped cross section by an upper slab 12, a lower slab 14, and a pair of right and left corrugated steel plates 16 connecting these. I have. Each corrugated steel plate 16 includes a corrugated steel plate main body 16A and an upper end flange portion 16B joined to an upper end thereof. The corrugated steel sheet web bridge 10 is constructed for each block of a predetermined length by overhanging construction.
[0022]
This figure shows the corrugated steel web bridge 10 at the time when the erection of the block B (n-1) on the front side of the head block B (n) is completed. At this time, the head block B (n) is The construction of the lower slab 14 and the corrugated steel plates 16 has been completed, but the construction of the upper slab 12 has not been performed yet.
[0023]
FIG. 2 is a perspective view showing a process of erection of the corrugated steel sheet web bridge 10. FIGS. 3 and 4 are a side view and a cross-section orthogonal to the bridge shaft, respectively, showing the erection process. FIG. 4 is a cross-sectional view orthogonal to the bridge axis in the first block B (n). The steps (a) to (d) in FIGS. 3 and 4 correspond to the steps (a) to (d) in FIG.
[0024]
The erection of the corrugated steel web bridge 10 is performed as follows.
[0025]
First, as shown in FIG. 1, a suspension supporter 100 for lower floor slab construction in which a simplified formwork 102 is attached to a pair of corrugated steel plates 16 constituting a top block B (n) on which no upper slab slab has been constructed. In the suspended state, as shown in FIG. 2A, a pair of corrugated steel plates 16 constituting a block B (n + 1) next to the head block (n) is erected in advance. The preceding installation of each corrugated steel plate 16 is performed using a crane or the like.
[0026]
At the time of this preliminary erection, a precast corrugated steel plate 18 in which a part of the lower floor slab 14 is precast at the lower end of the corrugated steel plate 16 is used as each corrugated steel plate 16. As shown in FIG. 5 which is a detailed view of a V part in FIG. 4, the precast corrugated steel sheet 18 has a configuration in which a concrete block 32 having a substantially rectangular cross section is embedded and joined to the lower end of the corrugated steel sheet body 16A. It has become. At the time of this embedded joining, a plurality of reinforcing bars 34 are embedded in the concrete block 32 with their tips protruding toward the center in the direction orthogonal to the bridge axis.
[0027]
Next, as shown in FIG. 2B, the suspension supporter 100 is moved to the pair of corrugated steel plates 16 erected in advance, and is installed at the position of the next block B (n + 1).
Then, the plurality of precast ribs 22 constituting the upper floor slab 12 of the head block B (n) are extended between the upper ends of both corrugated steel plates 16 at predetermined intervals in the bridge axis direction and extend in the bridge axis orthogonal direction. To place.
[0028]
When this arrangement is completed, as shown in FIG. 2 (c), a plurality of precast plates 24 are laid on the precast ribs 22, and the reinforcing steel and the upper floor slab side fastening steel are arranged on these precast plates 24. At the same time, rebar assembly of the lower floor slab 14 is performed on the simplified formwork 102 of the next block B (n + 1).
[0029]
Then, as shown in FIG. 2D, in the head block B (n), the upper floor slab concrete 26 is poured using the precast rib 22 and the precast plate 24 as a formwork, and in the next block B (n + 1), A lower floor slab concrete 28 is poured so as to cover the concrete block 32, and its curing is aimed at. Thereafter, in the top block B (n), prestress is introduced into the upper deck slab laterally tightened steel material 30 to perform lateral tightening of the upper slab concrete 26, and insert and tension the outer cable.
[0030]
When the erection of the first block B (n) is completed by the above steps, the erection of the next block B (n + 1) is performed by the same steps, and thereafter the erection by overhanging is performed in the same manner.
[0031]
As described in detail above, the method of erection of the corrugated steel sheet web bridge 10 according to the present embodiment uses the pair of corrugated steel sheets 16 constituting the top block B (n) on which the upper slab is not installed, for mounting the lower slab. In a state where the suspension supporter 100 is suspended, a pair of corrugated steel plates 16 constituting a block B (n + 1) next to the head block B (n) are erected in advance, and then suspended on these erected corrugated steel plates 16. The shoring 100 is moved, and in this state, the construction of the lower slab 14 constituting the next block B (n + 1) and the construction of the upper slab 12 constituting the head block B (n) are performed. Therefore, the upper floor slab 12 and the lower floor slab 14 can be constructed in parallel in separate blocks, thereby increasing construction efficiency. In addition, the use of the suspension supports 100 allows the construction of the lower floor slab 12 to be performed to some extent efficiently.
[0032]
In particular, in the present embodiment, as each corrugated steel plate 16 used for the preceding erection, a precast corrugated steel plate 18 in which a concrete block 32 constituting a part of the lower floor slab 14 is embedded and joined at the lower end thereof is used. Therefore, it is not necessary to cast concrete on the lower surface of the lower end flange portion of the corrugated steel sheet as in the related art. For this reason, it is possible to eliminate the concern of a decrease in integration due to the occurrence of bubbles and breathing due to reverse hit as in the related art, thereby increasing the bonding strength between the corrugated steel plate 16 and the lower floor slab 14 to achieve sufficient durability. Property can be ensured.
[0033]
Moreover, in the present embodiment, the adoption of the precast corrugated steel sheet 18 makes it possible to eliminate the lower end flange portion and the angle dowel of the corrugated steel sheet 16, so that the manufacturing cost of the corrugated steel sheet 16 can be reduced, and as a result, Work costs can be reduced.
[0034]
Further, in the present embodiment, the portion where the reinforcement is dense near the joint with the corrugated steel plate 16 in the lower slab 14 is precast, so that on-site work can be reduced, thereby shortening the construction period. be able to.
[0035]
Further, in the present embodiment, the upper floor slab 12 is constructed such that the plurality of precast ribs 22 are bridged between the upper ends of the pair of corrugated steel plates 16 at predetermined intervals in the bridge axis direction, and the upper After laying a plurality of precast plates 24, the precast ribs 22 and the precast plates 24 are used as a formwork, and the upper floor concrete 26 is cast. The construction of the upper slab 12 can be performed more easily than the construction of the upper slab by erecting a shoring and extending the erection beam from the constructed overhanging slab portion. Thus, not only the construction of the lower slab 14 but also the construction of the upper slab 12 can be simplified.
[0036]
In the above embodiment, the case where a pair of corrugated steel plates 16 are provided on both sides of the lower floor slab 14 in the direction orthogonal to the bridge axis has been described. However, even in the case where the corrugated steel plates 16 are provided at three or more locations, the above embodiment is also applicable. By adopting the same erection method, the same operation and effect as in the above embodiment can be obtained.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a corrugated steel sheet web bridge to which a method of erection according to an embodiment of the present invention is applied, in a state of being erected. FIG. 2 is a perspective view showing a erection step of the corrugated steel sheet web bridge. FIG. 3 is a side view showing the erection process. FIG. 4 is a cross-sectional view orthogonal to the bridge shaft showing the erection process. FIG. 5 is a diagram showing a precast corrugated steel plate used in the present embodiment as a detailed view of a V part in FIG. [Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Corrugated steel plate web bridge 12 Upper floor slab 14 Lower floor slab 16 Corrugated steel plate 16A Corrugated steel plate main body 16B Upper end flange part 18 Precast corrugated steel plate 22 Precast rib 24 Precast plate 26 Upper floor slab concrete 28 Lower floor slab concrete 30 Upper floor slab side tightening steel material 32 Concrete Block 34 Reinforcing bar 100 Suspension support 102 Simple formwork B (n-1) Block B (n) on the near side First block B (n + 1) Next block

Claims (2)

In a method of erection of a corrugated steel sheet web bridge extending in the bridge axis direction so as to form a box-shaped cross section with an upper slab, a lower slab, and a plurality of corrugated steel sheets connecting them, by overhanging construction for each block of a predetermined length. ,
A plurality of corrugated steel sheets constituting the block next to the above-mentioned top block were erected in advance in a state in which the suspension support for the lower deck slab was suspended on the plurality of corrugated steel sheets constituting the top block without the upper slab. After that, the suspension support is moved to these pre-installed corrugated steel plates, and in this state, the construction of the lower slab constituting the next block and the construction of the upper slab constituting the top block are performed. Is composed of
Each of the corrugated steel sheets used for the preceding erection is configured to use a precast corrugated steel sheet in which a concrete block constituting a part of the lower floor slab is embedded and joined at a lower end portion of the corrugated steel sheet. Method of erected corrugated steel web bridge. The construction of the upper floor slab, while extending a plurality of precast ribs at predetermined intervals in the bridge axis direction between upper ends of the plurality of corrugated steel plates, and after laying a plurality of precast plates on these precast ribs, The method for erection of a corrugated steel sheet web bridge according to claim 1, wherein the method is performed by placing an upper floor slab concrete using the precast ribs and the precast plates as a formwork.

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