JP3460572B2 - Substructure of road viaduct - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substructure of a viaduct for a road mainly used for roads.

[0002]

2. Description of the Related Art Road bridges include so-called road viaducts that are continuously constructed in urban areas in addition to narrowly defined bridges that cross rivers, straits and the like. From the viewpoint of efficient land use, such a viaduct for roads is constructed continuously in the space on the road, railroad or river,
When roads and roads or roads and railroads intersect in a plane, by constructing these roads as viaducts, it becomes possible to eliminate traffic congestion.

When constructing a road viaduct on an in-use road or railway, the following problems occur.

That is, in order to secure horizontal rigidity in the direction perpendicular to the bridge axis, the substructure of the viaduct for a road generally requires the foundation beam 1 as shown in FIG. Therefore, for example, when the track 2 is in service as a commercial line as shown in FIG. 3 (a), in order to construct a viaduct for a road on the track site, first, as shown in FIG. Was temporarily relocated to a side site of the planned construction site for the road viaduct, and then the track 3 was used as a commercial line during the construction period while the substructure 4 of the road viaduct having the foundation beam 1 was used. To construct. After the substructure 4 of the viaduct for roads was completed, it was general to remove the temporary track 3 and restore the original track 2 to its original condition.

[0005]

However, in such a procedure, it is necessary to secure a site for laying the temporary track 3 on the side of the road viaduct during the construction period.
In addition to the problem of land acquisition costs, it was extremely difficult to construct a viaduct for roads on railways in densely populated areas where private houses were approaching.
Even if the existing ground road is switched to an elevated road, a site for laying a temporary road must be secured beside the road viaduct during the construction of the road viaduct. Problem arises.

The present invention has been made in consideration of the above-mentioned circumstances, and an elevated road is provided above the existing road or railroad while the existing road or railroad is used as it is without requiring extra land acquisition. An object is to provide a substructure of a viaduct for roads that can be constructed.

[0007]

In order to achieve the above object, the substructure of the viaduct for a road according to the present invention is, as described in claim 1, located at a position opposite to a footing provided on a pile. Form a ramen structure from a pair of columnar piers that are respectively erected upright and a beam that bridges the top of the columnar pier, and configure the ramen structure with a reinforced concrete structure or a steel reinforced concrete structure, and the pair of columnar piers and Deformation of the rigid frame structure when a horizontal force is applied by arranging brace members having an inverted V shape in the in-plane space including the beams so that their lower ends are joined near the base of the columnar pier. Is configured so that it can be suppressed by the rigidity of the brace member in the horizontal direction orthogonal to the bridge axis without installing a foundation beam.

The substructure of the viaduct for a road according to the present invention is such that a predetermined energy absorbing damper is interposed between the beam and the vicinity of the top of the brace.

In the substructure of a viaduct for a road according to the present invention, an inverted V-shaped brace material is joined to an in-plane space including a pair of columnar piers and beams, the lower ends of which are joined near the base of the columnar pier. Since the bracing material ensures the rigidity in the horizontal direction orthogonal to the bridge axis, the deformation of the rigid frame structure when a horizontal force acts in that direction is sufficient without installing a foundation beam. Suppressed to.

As a structural type constituting the ramen structure, either a reinforced concrete structure or a steel frame reinforced concrete structure is used.

The structure, material type and arrangement method of the brace material are arbitrary, and may be resistant to both directions of compression and tension, or may be resistance only to the direction of tension. Further, as the material thereof, a steel frame material, a PC steel wire or the like can be used.

Here, the vicinity of the top of the inverted V-shaped brace material may be directly joined to the vicinity of the center of the beam, but if a predetermined energy absorbing damper is interposed between them, it will be The vibration energy can be absorbed by the energy absorbing damper, and the sway of the viaduct for roads can be quickly converged.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a substructure of a viaduct for a road according to the present invention will be described below with reference to the accompanying drawings. It should be noted that parts and the like which are substantially the same as those of the conventional technique are designated by the same reference numerals and the description thereof is omitted.

FIG. 1 is a front view of a lower structure of a viaduct for a road according to the present embodiment as viewed from the bridge axis direction. As can be seen in the figure, the substructure 1 of the viaduct for a road according to the present embodiment
0 is a pair of columnar piers 11 and 11 which are erected at positions facing each other, and a beam 12 bridged over the tops of the columnar piers.
The frame structure 13 is formed from the above, and the brace material 14 having an inverted V shape is arranged in the in-plane space including the pair of columnar piers 11, 11 and the beam 12. Here, the columnar pier 11 is erected on the footing 17 provided on the pillar 16 after the pile 16 has been driven therein.

A rigid frame structure 1 consisting of a pair of columnar piers 11, 11 and a beam 12 bridged on the top of the columnar piers.
3 is, for example, a reinforced concrete structure, and a brace material 14
Can be, for example, a steel structure.

The brace material 14 is joined near the center of the beam 12 via an energy absorbing damper 15 near the top of the brace material 14 and at both lower ends thereof.
The pair of columnar bridge piers 11 and 11 are joined near the bases thereof, respectively.

The energy absorption damper 15 can be formed by forming a large number of slits in a normal thin steel plate, or can be formed by an extremely soft steel. The energy absorbing damper 15 is preferably detachably attached between the brace member 14 and the beam 12 so that it can be replaced during maintenance.

In order to construct the substructure 10 for a viaduct for a road according to this embodiment, first, columnar piers 11, 11 are erected on both sides of a track 2 which is in service as a commercial line, and a beam is provided near its top. Ramen structure 13 spanning 12
To build. Next, the brace material 14 and the energy absorption damper 15 are attached to the rigid frame structure 13 to complete the substructure 10 of the viaduct for road.

Here, since it is not necessary to construct a foundation beam connecting the legs of the pillar pier 11, it is not necessary to replace the track 2 during the construction period.

After the substructure 10 of the viaduct for roads is constructed, the superstructure 5 for roads including bridge girders, floor slabs, etc. is bridged in the bridge axial direction.

In the substructure 10 for a viaduct for a road according to the present embodiment, a pair of columnar piers 11, 11 and a beam 12 are provided.
Since the brace material 14 is arranged in the in-plane space including the, and the rigidity of the horizontal direction orthogonal to the bridge axis is secured by the brace material, the deformation of the rigid frame structure 13 when a horizontal force acts in the direction is generated. , It is sufficiently suppressed without installing foundation beams.

As described above, according to the substructure 10 of the viaduct for a road according to the present embodiment, it becomes possible to sufficiently secure the rigidity in the horizontal direction orthogonal to the bridge axis by the brace member 14, and thus the conventional structure can be obtained. It is possible to omit the foundation beam, which was indispensable for road viaducts. Therefore,
Since it is not necessary to construct a foundation beam as a foundation work requiring a great cost and a construction period, it is possible to reduce the construction period and the construction cost.

Further, in the conventional case, because of the foundation beam construction,
It is necessary to secure a land on the side of the substructure 4 of the viaduct for roads, and then lay a track 3 on the site to replace the track. It was extremely difficult to construct a viaduct for roads in such a densely populated area, but according to this embodiment, the foundation beams can be omitted, so there is no need to change the track for performing the construction of a viaduct for roads. Therefore, it is not necessary to acquire land alongside the viaduct for roads. Therefore, it is possible to construct the substructure of the road viaduct at a much shorter construction time and at a lower cost than before, and also to construct the road viaduct even in a dense area where private houses are approaching the side of the road viaduct. It becomes possible to do.

Further, since the horizontal rigidity of the entire substructure 10 can be adjusted by changing the thickness, width or material of the brace member 14, the road having excellent earthquake resistance considering the frequency characteristics of seismic waves and the like. It is possible to construct the substructure 10 of the commercial viaduct.

Further, according to the present embodiment, since the vicinity of the top of the inverted V-shaped brace member 14 is joined to the beam 12 via the energy absorbing damper 15, it is possible to prevent seismic motion along the direction orthogonal to the bridge axis. On the other hand, the energy absorbing damper 15 interposed between the ramen structure 13 and the brace member 14 absorbs the vibration energy thereof, and promptly converges the sway of the substructure 10 of the viaduct for roads and the entire viaduct.

On the other hand, the energy of the input seismic motion is consumed as the hysteresis attenuation of the energy absorption damper 15,
The ramen structure 13 and the brace material 14, which are the main structures of the substructure 10 of the viaduct for roads, maintain their soundness with little damage. Therefore, after the earthquake,
By replacing the energy absorbing damper 15 with a new one, the use of the road viaduct can be continued as before.

Further, according to the substructure 10 of the viaduct for a road according to the present embodiment, the displacement design centering on the deformation performance of the energy absorption damper 15 is possible, and it depends on the complicated RC deformation performance as in the past. A more rational design is possible than the design method.

Further, according to the substructure 10 of the viaduct for a road according to the present embodiment, it is possible to restore the residual deformation due to the earthquake of the ramen structure 13 by taking the reaction force from the brace material 14, and at the time of the earthquake It is possible to easily control the damage of the.

In this embodiment, the superstructure 5 of the viaduct for roads was not mentioned in detail, but its structural form is arbitrary, and it goes without saying that a conventional (ramen type) superstructure using a heavy concrete slab is used. Of course, those that use hollow bridge girders, those that use lightweight materials on the balustrade, and those that span the desired number of girders that support only one lane, such as two lanes, three lanes, etc. Become.

Further, in the present embodiment, the hysteretic damping type is used as the energy absorbing damper, but the energy absorbing damper is not limited to such type, and the viscous damping type or the friction damping type can also be used. Is.

Further, in the present embodiment, the case where the substructure of the road bridge viaduct is constructed above the existing railway track has been described, but it can be similarly applied to the case where the substructure of the road bridge viaduct is constructed. In such a case, substantially the same operational effects as those of the above-described embodiment are achieved.

Further, it goes without saying that the present invention can be applied to the case where it is constructed on a vacant lot that is not used as a railway or a road, and even in such a construction, the construction work can be omitted because the construction of the foundation beam can be omitted. It is almost the same as the above-described embodiment in that the shortening and the construction cost can be reduced.

[0033]

[0034]

As described above, according to the substructure of the viaduct for a road according to the invention of claim 1, since the brace member can sufficiently secure the rigidity in the horizontal direction orthogonal to the bridge axis, It is possible to omit the foundation beams, which were indispensable in the conventional substructure of the viaduct for roads, and it is possible to reduce the construction period and the construction cost.

Further, according to the substructure of the road viaduct according to the invention of claim 2, the vibration energy at the time of the earthquake is absorbed by the energy absorbing damper, and the sway of the road viaduct in the direction orthogonal to the bridge axis is promptly obtained. There is also an effect that it becomes possible to converge.

[0036]

[Brief description of drawings]

FIG. 1 is a front view of a lower structure of a viaduct for a road according to the present embodiment as viewed from a bridge axis direction.

FIG. 2 is a front view of a lower structure of a viaduct for a road according to a conventional technique as viewed from a bridge axis direction.

FIG. 3 is a construction diagram showing a procedure for constructing a substructure of a viaduct for a road in a conventional technique.

[Explanation of symbols]

1 foundation beam 2 orbits 5 Superstructure of viaduct for road 10 Substructure of viaduct for road 11 column piers 12 beams 13 Ramen structure 14 Brace material 15 Energy absorption damper

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-8-92914 (JP, A) JP-A-10-298916 (JP, A) US Pat. 5533307 (US, A) Ramen with brace and steel damper Seismic retrofitting method for viaducts, 52nd Annual Scientific Lecture Meeting of Japan Society of Civil Engineers, Japan, Japan Society of Civil Engineers, September 1997, pp. 218-219 (58) Fields investigated (Int.Cl. ⁷ , DB name) E01D 19 / 02 E01D 21/00 E01D 1/00

Claims (2)

(57) [Claims] 1. A ramen structure is formed from a pair of columnar piers, each of which is erected at a position opposite to a footing provided on a pile, and a beam bridged to the top of the columnar pier. The ramen structure is made of reinforced concrete structure or steel frame reinforced concrete structure, and the lower ends of brace members forming an inverted V shape in an in-plane space including the pair of columnar piers and the beams are joined near the base of the columnar piers. By arranging in such a manner, the deformation of the rigid frame structure when a horizontal force acts can be suppressed by the rigidity of the brace material in the horizontal direction orthogonal to the bridge axis without installing a foundation beam. Substructure of viaduct for road. 2. An underpass structure for a road viaduct according to claim 1, wherein a predetermined energy absorbing damper is interposed between the beam and the vicinity of the top of the brace member.