JPH0765297B2 - How to erection a cane ramen bridge - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a method for constructing a cane ramen bridge mainly made of concrete having a span of several tens of meters.

[Conventional technology]

Conventional concrete bridges with medium-scale spans (branches of about 50 m) are generally erected by shoring or continuously erected by extrusion.

Of these, bridge construction by shoring is generally used for cast-in-place concrete construction and precast block construction for the cane ramen bridge.

[Problems to be Solved by the Invention]

However, since the construction by shoring depends on the conditions under the bridge, it is not suitable for continuous construction and bridges with multiple spans.
In addition, construction in a V-shaped valley is uneconomical because large-scale erection equipment is required. On the other hand, although the extrusion method is suitable for multi-span construction, the temporary equipment is too large for construction with a single span or several spans, and is considered to be unsuitable in terms of cost. In other words, for the medium-scale spans of concrete bridges, a general-purpose economical bridge temporary construction method has not yet been established.

The present invention was invented under the circumstances as described above, the on-site construction is simplified, and the erection materials used can be reduced,
Therefore, it is an object of the present invention to provide a method for erection of a cane ramen bridge which can reduce the construction period construction cost and can be applied to multi span span bridges.

[Means for Solving the Problems]

Hereinafter, the outline of the present invention will be described using the reference numerals of the drawings corresponding to the embodiments.

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to a main bridge pier 1 constructed at predetermined intervals, an upper floor slab 2 installed between the main piers 1, a diagonal member 3 for diagonally supporting the upper floor slab 2 in a cane shape, and a diagonal member if necessary. The construction is performed by applying the structure of a cane ramen bridge which is installed on 3 and is composed of columns 4 supporting the upper floor slab 2.

In the erection method of the present invention, after the main pier 1 is constructed, the hinge 6 is provided at the diagonal member supporting position of the main pier 1, and the diagonal member 3 is placed on the hinge 6.
Is built with temporary support. The diagonal member 3 may be made of precast concrete or cast in place. Next, the diagonal member 3 is rotated around the hinge from the temporarily supported state, and is obliquely supported to the main pier 1 at a predetermined height by the suspending member 5 made of high-tensile steel or the like. From this state, the tension of the suspension member 5 is adjusted to withstand the load applied later, and the upper deck 2 is continuously erected on the main bridge pier 1 and the diagonal member 3 and the span of one span is maintained. Complete the construction. For bridges with multiple diameters, this work can be repeated or laid in parallel.

In the completed system, the suspending member 5 at the time of installation works as a tension member that bears the reaction force of the upper work, and the member cross sections of the diagonal member 3 and the upper floor slab 2 can be greatly reduced.

〔Example〕

Next, as an example, regarding the construction of a bridge with a span of about 50 m,
A description will be given with reference to the drawings.

In the examples described later, the upper floor slab 2 has a continuous structure with 5 spans.

Example-1 Example-1 is based on the assumption that the continuous span bridge will be constructed in the air, and is constructed in one direction.

A temporary support hinge 6 is installed at the diagonal support position of the main pier 1 (see FIG. 1).

The diagonal member 3 is vertically assembled on the temporary supporting hinge 6 by a precast member or a cast-in-place concrete member.

The slant member 3 is installed at a predetermined erection position by the oblique suspension method or a lifting machine, and is fixed with the high-strength steel as the suspending member 5 protruding from the main pier 1 (see FIG. 2).

The support columns 4 are provided on the diagonal member 3 at predetermined intervals (in the present embodiment, there is only one position on the diagonal member 3).

The upper deck slab 2 is constructed sequentially from the main pier 1 on one side (see Fig. 3). If the cross-sectional force of the diagonal members 3 becomes excessive due to the weight of the upper deck 2 and the work load, a second suspension member 5a made of high-tensile steel is installed from the main pier 1 to adjust the cross-sectional force (No. (See Fig. 4). The construction of the upper floor slab 2 is constructed by a pre-cast method or a cast-in-place concrete method for every one span, and pre-stress is introduced to the cross-sectional force at the time of erection.
When this procedure is repeated and the construction of the upper deck 2 from the main pier 1 to the main pier 1 opposite to the main pier 1 is completed, the prestress of the completed system is introduced in addition to the prestress at the time of erection (see Figs. 5 to 7). ).

Repeat steps (1) to (3) above to construct the next span.

Example-2 Example-2 is a case where a construction yard can be installed, and the upper floor slab 2 can be erected from an arbitrary portion (for example, the central portion). For example, the construction is performed by the following procedure.

By the same procedure as in Example-1, the diagonal members 3 are vertically assembled on the temporary supporting hinges 6 for the two adjacent main piers 1.

In the same manner as in Example-1, the diagonal slanting method or the lifting machine is used to install the opposing slant members 3 at predetermined erection positions and fix them with the suspending members 5 projecting from the main pier 1 (see Fig. 8).

Supports 4 are provided on both diagonal members 3 at predetermined intervals. If the sectional force of the diagonal member 3 becomes excessive due to the weight of the upper floor slab 2 and the work load, the second suspending member 5a is installed to adjust the sectional force (see FIG. 9).

The central upper floor slab 2 is erected and both diagonal members 3 are connected (No. 10
See figure).

After connecting the both diagonal members 3, the unnecessary second hanging member 5a is removed, and the upper floor slabs 2 on both sides are sequentially erected. When the construction of the upper floor slab 2 between both main piers 1 is completed, the prestress of the completed system is introduced in addition to the prestress at the time of erection (Fig. 11-Fig.
(See Figure 12).

Repeat steps (1) to (3) above to construct the next span.

Example-3 In Example-3, the upper floor slab 2 is a composite slab consisting of steel plate 2b and cast-in-place concrete 2a as shown in Fig. 18 (in the figure, the right half is the center of the span and the left half is the cross beam part). It is a cross section) and the construction is performed according to the following procedure.

By the same procedure as in Example-2, the opposing diagonal members 3 are installed at the predetermined erection positions for the two adjacent main piers 1 and are fixed by the suspension members 5 projecting from the main pier 1 (Fig. 13). reference).

Supports 4 are provided on both diagonal members 3 at predetermined intervals. If the sectional force of the diagonal member 3 becomes excessive due to the weight of the upper floor slab 2 and the work load, the second suspending member 5a is installed to adjust the sectional force (see FIG. 14).

Formwork that also serves as a support for the upper floor slab 2 of the synthetic slab structure
Install 2b (see Figure 15).

Precast concrete 2a by placing concrete 2a on steel plate 2b to form upper floor slab 2 (see Fig. 16). Remove unnecessary second suspension material 5a and add it to the prestress during erection. Introduce (No.
(See Figure 17).

Repeat steps (1) to (3) above to construct the next span.

[Advantages of the Invention] This is a construction method in which the characteristics of concrete and hanging materials in the structure of a cane ramen bridge are combined, and the member cross section can be suppressed. That is, at the time of erection, the diagonal members and the hanging members statically bear the load according to the dead weight and the top load such as the floor slab. The combination can bear the axial force and bending in the rigid frame structure and reduce the member cross section against buckling.

Since no support work is used, it can be installed regardless of the construction conditions at the bridge.

Since a precast member can be used, the construction period can be shortened.

[Brief description of drawings]

1 to 7 are side views of a cane ramen bridge showing the construction procedure in Example-1 as an embodiment of the present invention, and FIGS.
Figure 12 is a side view showing the construction procedure of Example-2,
13 to 17 are side views showing the construction procedure in Example-3, and FIG. 18 is a cross-sectional view in the direction perpendicular to the bridge axis in Example-3. 1 ... Main bridge pier, 2 ... Upper slab, 2a …… Spot-cast concrete, 2b …… Synthetic slab method and supporting formwork, 3 ……
Slanting material, 4 ... Support pillar, 5 ... Hanging material, 5a ... Second hanging material,
6 ... Hinges for temporary support

Claims (2)

[Claims] 1. A cane ramen bridge comprising a main bridge pier constructed at predetermined intervals, an upper deck slab installed between the main bridge piers, and a diagonal member diagonally supporting the upper deck slab in the shape of a cane. A method of erection, in which after construction of the main pier, a hinge is provided at the diagonal support position of the main pier, and the diagonal constructed in the temporarily supported state on the hinge is rotated around the hinge and hung at a predetermined height. Supporting the main bridge pier diagonally with timber and adjusting the tension of the hanging material so as to withstand the overload that acts later, while continuously installing the upper deck on the main pier and the diagonal timber. A method of erection of a cane ramen bridge characterized by. 2. An upper middle portion of the diagonal member is provided with one or more columns while adjusting the tension of the hanging member.
The method for constructing a cane ramen bridge according to claim 1, wherein the upper deck slab is continuously erected on the main bridge piers, the columns and the diagonal members.