JP4359731B2 - Method of replacing concrete floor slab bridge with steel slab and structure of replacing concrete floor slab bridge with steel slab - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to the replacement of a concrete bridge slab bridge to a steel slab, which replaces a concrete slab with a steel slab, such as a viaduct bridge that supports an RC slab by a main girder extending in the direction of the bridge axis. The present invention relates to a method and a structure for replacing a concrete slab bridge with a steel slab.
[0002]
[Prior art]
As a structure of a bridge such as a viaduct, there is a structure in which a reinforced concrete floor slab (hereinafter referred to as an RC floor slab) is supported by a main girder extending in a bridge axis direction. The main girder and the RC floor slab are coupled so that a gibber planted in the main girder is buried in the RC floor slab so that shear force can be transmitted.
[0003]
The RC floor slab is a work in which work is troublesome and requires a long period of time because concrete is placed with steel bars in the formwork at the construction site. In addition, the weight is heavy and the dead load is large.
[0004]
Recently, the number of bridges that need to be replaced due to aging of such RC slabs is increasing. However, the replacement of RC slabs is done by chopping and removing existing RC slabs as before. It is common to rebuild the RC floor slab.
[0005]
[Problems to be solved by the invention]
However, it is extremely troublesome to dismantle and remove the supported part (joint part with the main girder) of the existing RC floor slab, and the construction of a new RC floor slab after the removal of the old floor slab is also newly made. It takes a long time because it is necessary to provide a formwork and lay steel bars inside to place concrete.
[0006]
For this reason, there is a problem that the traffic regulation period which must be performed during the bridge slab replacement is long.
[0007]
In recent years, it is desirable to widen the floor slab when the floor slab is replaced due to an increase in traffic volume. However, as described above, the RC floor slab is heavy, so the substructure of the bridge including the girder must be strengthened. It is necessary to change the structure of the entire bridge.
[0008]
The present invention has been made in view of the above-mentioned problem, and enables the re-installation of the floor slab in a short traffic regulation period. Further, the weight reduction of the floor slab allows the widening without changing the substructure of the bridge. The purpose of this project is to provide a method for replacing concrete floor slab bridges with steel slabs and a structure for replacing concrete floor slab bridges with steel slabs.
[0009]
[Means for Solving the Problems]
The method for replacing a concrete floor slab bridge with a steel floor slab according to the present invention that achieves the above object is the bridge comprising a concrete floor slab supported by a main girder extending in the direction of the bridge axis. After the replacement steel plate member is fixed to the main girder via the support member so that the main girder floor slab part excluding the bonded supported part, which is the coupling part with the main girder, can be supported from the lower surface side, An upper surface of the supported portion that cuts between the support portion and the floor slab portion between the main beams to remove the floor slab portion supported by the replacement steel plate member and covers at least the upper surface of the combined supported portion The steel plate is fixed so as not to move, the fixing of the support member to the main girder is released, the replacement steel plate member is raised to a position that matches the upper surface steel plate of the supported portion, and the support member is again attached to the main girder. Fixed and supported Combining an upper surface steel plate and the replacement-parts, characterized by replacing the main beam between the slab region in the replacement-parts.
[0010]
Further, the structure for replacing the concrete slab bridge with the steel slab is such that the concrete slab is supported by a main girder extending in the direction of the axis of the bridge, and the connecting portion of the concrete slab with the main girder The concrete floor slab of the main girder floor slab part excluding the joint supported part is removed, and only the joint supported part remains on the main girder, and the supported part upper surface steel plate is formed on the upper surface of the joint supported part. And a replacement steel plate member is fixed to the main girder via a support member, and the supported portion top surface steel plate and the replacement steel plate member are combined and integrated. It is characterized by being configured.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings.
[0012]
FIG. 1 (A) is a cross-sectional view orthogonal to the bridge axis of the bridge of the RC floor slab before replacement, and (B) is a cross-sectional view of the bridge after replacement.
[0013]
In the bridge 1 ′ before restretching shown in FIG. 1 (A), a reinforced concrete floor slab (RC floor slab) 20 is constructed on a girder including three main cross-sectional I-shaped beams 10 extending in the direction of the bridge axis. The main girder 10 supports the bridge piers (not shown) arranged at predetermined intervals in the bridge axis direction.
[0014]
On the upper surface of the upper flange 10F of the main girder 10, a diver 11 is erected, and the diver 11 is immersed in the RC floor slab 20 to couple the main girder 10 and the RC floor slab 20 so as to transmit a shearing force. Yes. The part supported by the main girder 10 of the RC floor slab 20 is formed so that the back side protrudes by an oblique haunch and is thicker than the other parts. Hereinafter, a haunch part is added to the upper flange 10F of the main girder 10. The width portion is referred to as a joint supported portion 21, and the portion having a uniform thickness between the joint supported portions 21 is referred to as an inter-main girder floor slab portion 22.
[0015]
Such an RC floor slab 20 is replaced with a steel floor slab using an example of a replacement method according to the present invention to form a steel floor slab bridge 1 as shown in FIG.
[0016]
First, as shown in FIG. 2 which is a partial cross-sectional view, a support cross beam 31 as a support member is fixed to the main girder 10, and a plurality of them are arranged at predetermined intervals in the bridge axis direction.
[0017]
The illustrated support cross beam 31 is formed of a steel plate having a predetermined thickness with a flange 31A having a predetermined width on the upper edge of a plate portion having a predetermined height, and its side end is fixed to the belly plate of the main girder 10. It is fixed to the main girder 10 by being fastened to the fastening plate portion 32A of the support fitting 32 by bolts and nuts (not shown), the plate surface is orthogonal to the bridge shaft, and the upper edge is a predetermined distance from the back surface of the RC floor slab 20 It is provided horizontally so as to be.
[0018]
The support fitting 32 is formed to a predetermined length by a steel having a T-shaped cross section, and is fixed to the stomach plate 10W of the main girder 10 in a vertical state by a flange thereof, for example, by welding, so that the fastening plate portion 32A is orthogonal to the bridge axis. It is provided so as to protrude. The fastening plate portion 32A is set to a predetermined length in the vertical direction so as to allow movement of the support lateral beam 31 described later.
[0019]
Next, as shown in FIG. 4 which is an AA cross-sectional view of FIG. 3 and FIG. 3 and FIG. 5 which is a bottom view of FIG. The replacement structure 33 is inserted between the lower surface of the plate 20 and integrated with the support cross beam 31 by welding or fastening with bolts and nuts to form the support replacement structure 30.
[0020]
The replacement structure 33 is provided on the lower surface side of the replacement steel plate 33A as a replacement steel plate member having a width corresponding to the inter-main girder floor slab portion 22 excluding the bonded supported portion 21 supported by the main girder 10 of the RC floor slab 20. As shown in FIG. 6 which is a perspective view of the portion, a plurality of vertical beams 33B having a T-shaped cross section extending in the bridge axis direction are fixed by welding. The height is set so that it can be fitted with a predetermined tolerance between the upper edge of the supporting cross beam 31 fixed to the main girder 10 and the lower surface of the inter-main girder floor slab portion 22 of the RC floor slab 20, The length in the bridge axis direction is set so as to be supported by the plurality of support lateral beams 31.
[0021]
Here, as shown in FIG. 7, the replacement structure 33 is installed in a part of the bridge 1 where the support cross beam 31 corresponding to the length of the replacement structure 33 is not disposed: X In this insertion part: X, the replacement structure 33 is lifted in a horizontal state to a height corresponding to the space between the support cross beam 31 and the RC floor slab 20, and is shifted in the horizontal direction and positioned at a predetermined part. Do. The replacement steel plate 33A and the longitudinal beam 33B of the replacement structure 33 adjacent to each other in the bridge axis direction are joined together by welding or bolts and nuts. Thereby, the longitudinal beam 33B becomes a strength member continuous in the bridge axis direction.
[0022]
As described above, when the replacement structure 33 is disposed between the support cross beam 31 and the RC floor slab 20 (inter-main girder floor slab portion 22) to form the support replacement structure 30, the replacement steel plate 33A becomes the main girder. It is located close to the lower surface of the interstitial slab portion 22, thereby enabling a state where the main girder slab portion 22 can be supported. At this time, the fixing position of the support cross beam 31 to the main girder 10 may be more positively adjusted so that the replacement steel plate 33A of the support replacement structure 30 is brought into contact with the lower surface of the floor slab portion 22 between the main beams. . Further, for a portion where the bottom surface of the main girder floor slab portion 22 is not horizontal, a replacement steel plate 33A is disposed obliquely corresponding thereto, or via a spacer 35 having a corresponding shape as shown in FIG. Disguise.
[0023]
Thereafter, the coupled supported portion 21 and the main girder floor slab portion 22 of the RC floor slab 20 are cut along a vertical plane parallel to the bridge axis. As a result, the main girder floor slab portion 22 is supported by the main girder 10 via the support replacement structure 30, and the main girder floor slab portion 22 is further appropriately subdivided and removed. As shown in FIG. 4, only the bonded supported portion 21 remains.
[0024]
Next, as shown in FIG. 9, a fixing cap 40 is put on and fixed to the remaining bonded supported site 21.
[0025]
The fixed cap 40 is fixed to the joint supported part 21 by fixing the side plates 42 with a predetermined height on the left and right sides of the lower surface of the top plate 41 as the supported part upper part steel plate at intervals corresponding to the width of the joint supported part 21. It is formed of a steel plate having a predetermined plate thickness in a substantially U-shaped cross section that opens to the lower side that can be fitted from the upper side. The top plate 41 protrudes outward by a predetermined amount from the left and right side plates 42 to form a coupling flange 41A, and the top plate 41 has a predetermined cap 40 as seen from the back side as shown in FIG. Filling holes 41B are formed at intervals, and fixed pins 41C having a predetermined length are implanted on the inner surface (lower surface).
[0026]
The fixing cap 40 is fixed to the coupled supported part 21 by forming a coupling hole 21A on the upper surface of the coupled supported part 21 at a position corresponding to the fixing pin 41C of the fixed cap 40, and an epoxy system in the coupling hole 21A. Then, the fixing pin 41C is matched with the coupling hole 21A and the coupling supported portion 21 is covered with the fixing cap 40, and the upper surface of the coupling supported portion 21 is fixed via the filling port 41B. And the top plate 41 of the fixed cap 40 by injecting and filling mortar.
[0027]
Thereafter, the support cross beam 31 of the support replacement structure 30 is supported by a jack or a crane, and the fixing of the support cross beam 31 to the support bracket 32 (that is, fixing to the main girder 10) is released, and the replacement steel plate 33A is fixed to the cap. 40, the support horizontal beam 31 is fixed to the support bracket 32 (main girder 10), and the side edge of the replacement steel plate 33A and the top plate 41 of the fixing cap 40 are joined. The flange 41A is fastened with bolts and nuts. Thereby, as shown in FIG. 11, the replacement of the main slab floor slab portion 22 of the RC floor slab 20 with the replacement steel plate 33A of the support replacement structure 30 is completed.
[0028]
After the replacement of the RC floor slab 20 to the steel floor slab is completed in this way, the upper surface can be paved with a predetermined thickness with asphalt or the like and used.
[0029]
According to the method as described above, the inter-girder floor slab portion 22 of the RC floor slab 20 is replaced with the replacement steel plate 33A of the support replacement structure 30 made of a steel plate, and the remaining RC floor slab 20 is joined. Since the RC floor slab 20 is replaced with a steel floor slab by coupling with the top plate 41 of the fixed cap 40 fixed to the support site 21, the coupled supported part site coupled to the main girder 10 of the RC floor slab 20 that is difficult to remove. It is possible to replace the steel plate with a steel slab without removing 21 and to perform the re-covering in a short time. Thereby, the traffic regulation period of the bridge in use can be shortened, and the influence on traffic can be minimized.
[0030]
Further, since the main inter-girder floor slab portion 22 made of reinforced concrete is replaced with the support replacement structure 30, the total weight can be reduced, and it is also possible to widen the bridge pier and the lower structure of the bridge. Is.
[0031]
Note that the configurations of the support replacement structure 30 and the fixed cap 40 are not limited to the above configuration example, and can be changed as appropriate. For example, as shown in FIG. 12, which is a perspective view corresponding to FIG. 6, the replacement structure 33 is bridged with a substantially U-shaped section steel 33C on the lower surface of the replacement steel plate 33A with its longitudinal direction as the bridge axis direction. A plurality of the fixing members 34 may be fixed in parallel in the width direction, and the coupling member 34 may be provided at a position corresponding to the support lateral beam 31.
[0032]
【The invention's effect】
As described above, according to the method for replacing a concrete slab with a steel slab according to the present invention, the floor slab part between the main girders excluding the joint supported part that is the joint part with the main girder of the concrete floor slab. After the replacement steel plate member is fixed to the main girder via the support member so that it can be supported from the lower surface side, the main part supported by the replacement steel plate member is cut by cutting between the bonded supported portion and the floor slab portion between the main beams. Remove the inter-girder floor slab part, fix the supported part upper surface steel plate covering at least the upper surface to the joint supported part so as to be immovable, release the fixing of the supporting member to the main girder, and replace the steel plate member with the supported part The support member is fixed to the main girder again, and the supported portion upper surface steel plate and the replacement steel plate member are coupled together, and the floor slab portion between the main beams is replaced with the replacement steel plate member. Thereby, since only the interstitial floor slab part is replaced with the replacement steel plate member without removing the joint supported part that is coupled to the main girder of the concrete floor slab that is difficult to remove, the replacement can be performed in a short time. Thereby, the traffic regulation period of the bridge in use can be shortened, and the influence on traffic can be minimized. Further, the total weight can be reduced, and the width can be widened without strengthening the bridge pier or the lower structure of the bridge.
[0033]
In addition, as a structure for replacing concrete floor slab bridges with steel slabs, in the bridges where the concrete slabs are supported by the main girder extending in the direction of the bridge axis, this is the connecting part with the main girder of the concrete slabs The concrete floor slab of the main girder floor slab excluding the bonded supported part is removed, and only the bonded supported part remains on the main girder, and the supported part upper surface steel plate is fixed to the upper surface of the bonded supported part. In addition, the replacement steel plate member is fixedly disposed on the main girder via the support member on the main girder floor slab portion, and the supported portion upper surface steel plate and the replacement steel plate member are combined and integrated. The replacement steel plate member replaces only the interstitial floor slab part without removing the bonded supported part that is coupled to the main girder of the concrete floor slab, which is difficult to remove, so that the replacement can be performed in a short time . Thereby, the traffic regulation period of the bridge in use can be shortened, and the influence on traffic can be minimized. Further, the total weight can be reduced, and the width can be widened without strengthening the bridge pier or the lower structure of the bridge.
[Brief description of the drawings]
FIG. 1A is a cross-sectional view orthogonal to a bridge axis of a bridge of an RC floor slab before being replaced, and FIG. 1B is a view of the bridge after being replaced with a steel deck using an example of the replacement method according to the present invention. It is sectional drawing.
FIG. 2 is a partial cross-sectional view of a bridge in a state where a supporting lateral beam is fixed.
FIG. 3 is a partial cross-sectional view of a bridge in a state in which a replacement structure is constructed by fixing the replacement structure to the support lateral beam.
4 is a cross-sectional view taken along the line AA in FIG. 3;
5 is a B arrow view corresponding to the bottom view of FIG. 3;
FIG. 6 is a partial perspective view of a replacement structure.
FIG. 7 is a conceptual diagram showing a method for installing a replacement structure.
FIG. 8 is a partial cross-sectional view of a bridge in a state where a floor slab portion between main girders is removed.
FIG. 9 is a partial cross-sectional view of a bridge in a state where a fixed cap is put on a coupled supported site.
FIG. 10 is a view of the fixed cap as viewed from the back side.
FIG. 11 is a partial cross-sectional view of a bridge in a state where a floor slab portion between main girders is replaced by a support replacement structure.
FIG. 12 is a perspective view of another configuration example of a replacement structure.
[Explanation of symbols]
1 Steel floor slab bridge 1 'RC floor slab bridge (concrete floor slab bridge)
DESCRIPTION OF SYMBOLS 10 Main girder 20 Concrete floor slab 21 Joint supported site 22 Main girder floor slab site 30 Support replacement structure 31 Support cross beam (support member)
33 Replacement Structure 33A Replacement Steel Plate (Substitution Steel Plate Member)
40 Fixed cap 41 Top plate (supported top surface steel plate)

Claims (2)

In a bridge where a concrete slab is supported by a main girder extending in the direction of the bridge axis,
The replacement steel plate member is fixed to the main girder via a supporting member so that the floor slab portion between the main girders excluding the coupled supported portion which is the coupling portion with the main girder of the concrete floor slab can be supported from the lower surface side. After that, by cutting between the combined supported portion and the main slab floor slab part to remove the main slab floor slab part supported by the replacement steel plate member,
The supported portion upper surface steel plate covering at least the upper surface of the combined supported portion is fixed immovably,
The fixing of the support member to the main girder is released and the replacement steel plate member is raised to a position that matches the upper surface steel plate of the supported portion, and the support member is re-fixed to the main girder and the upper surface of the supported portion. A method of replacing a concrete floor slab bridge with a steel deck by combining a steel plate and the replacement steel plate member and replacing the main girder floor slab portion with the replacement steel plate member. In a bridge where a concrete slab is supported by a main girder extending in the direction of the bridge axis,
The concrete floor slab of the inter-main girder floor slab part excluding the bonded supported part, which is a part of the concrete slab coupled with the main girder, is removed, and only the coupled supported part remains on the main girder, The supported portion upper surface steel plate is fixed to the upper surface of the coupled supported portion, and the replacement steel plate member is fixed to the main girder via the support member and disposed on the inter-main girder floor slab portion, and the supported portion A structure for replacing a concrete slab bridge to a steel slab, wherein the upper steel plate and the replacement steel plate member are combined and integrated.

Images