JPH1181242A - Precast block installation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the need to provide a rail along the overall length of a bridge surface, for running a truck provided at a rear support, when moving an installation truss forward; to prevent lifting of the rear support of the truss during movement; and to eliminate the need to reinforce a bridge body for receiving the reaction of the rear support traveling on the bridge surface during movement. SOLUTION: A precast block installation device includes: a truss 5, which has a longitudinally extending track 4 provided on its lower surface and which has a front support 2 and a rear support 3 suspended, respectively, from the front and rear ends of the lower surface; a first moving support 5 suspended over the track 4 in such a way as to be able to travel; and a second moving support 7 hungs on a trolley and suspended over the track 4 in such a way as to be able to travel. The precast block installation device has a rail 10 arranged on a bridge surface 8 and on which a truck 9 provided below the rear support 3 travels.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a precast block erection apparatus for a precast block bridge.

[0002]

2. Description of the Related Art Conventionally, there has been a precast block bridge in which precast blocks are sequentially joined to form a bridge between a plurality of piers erected at predetermined intervals for the purpose of simplifying construction and shortening the construction period. Has been built.

[0003] As one of means for erection of the precast block, one using a truss for erection is known.

In this method, as shown in FIG. 3A, for example, the erection truss 1a includes a rear support 2a and a central support 3a through which blocks can pass.
A temporary support 4a is provided at the front, and a rear support 2a,
The newly installed support 6a on the central column 3a near the tip of the overhang and the temporary column 4a at the front end of the next pier 5a
Is mounted on a precast block.

In order to move the erection truss 1a forward with the erection of the precast block, the truss 1a is rigidly connected to the rear strut 2a and the moving steel frame 7a fixed to the top of the pier 5a. 3 (b) to 3 (c) on a carriage provided on a rear trolley 2a running on rails arranged on a bridge surface and a transport trolley, and erection of a new precast block Is what you do.

[0006]

However, according to the conventional precast block erection means, when the erection truss 1a is moved forward, the rail for moving the bogie provided on the rear support 2a is connected to the bridge. The truss must be provided over the entire length of the surface and the work is complicated, and at the time of movement, the rear support 2a of the erection truss 1a rises up and is unstable. Since the reaction force of the column 2a acts over the entire length of the bridge, the load for erection of the bridge is taken into account, and as a result, the strength of the bridge must be increased by increasing the cross-sectional area of the bridge. There is also a problem.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems of the conventional means for erection of a precast block using an erection truss. A truss provided with an extending track and having a front support and a rear support provided at front and rear ends of the lower surface, respectively; a first movable support suspended on the track and capable of running on the track; A second moving support suspended from a trolley suspended in the vehicle, and a rail arranged on a bridge surface and provided with a bogie provided below the rear support on which the truck travels.

[0008] In the above structure, it is further preferable that the first and second movable struts are pivotable and movable in the width direction of the truss.

[0009]

Embodiments of the present invention will now be described with reference to the drawings.

FIGS. 1 and 2 show one embodiment of the present invention.
As shown in FIG. 1, a truss 5 mainly having a front strut 2 and a rear strut 3 respectively suspended at a front end and a rear end of a lower surface, and having a track 4 extending in a length direction on the lower surface, A first moving post 6 movably suspended on the track 4, a second moving post 7 suspended on a trolley (not shown) movably suspended on the track 4, and a bridge surface 8
Truck 9 arranged below and provided below the rear support 3
The rail 10 travels.

The first moving support 6 has a drive unit (not shown) having a pinion that meshes with a rack provided on the lower surface of the track 4 over the length thereof.

Further, a temporary fixing device to the pier can be selectively connected to the lower end of the first movable support column 6.

On the other hand, the second moving column 7 is suspended from a trolley (not shown) having a drive unit having a pinion that meshes with a rack provided on the lower surface of the track 4 over the length thereof. At the lower end, a suspension device for the precast block or a temporary fixing device to the pier can be connected.

In order to construct a precast block bridge using the embodiment of the present invention having the above configuration, FIG.
As shown in (a), the precast block 15 transported by a trailer to the rear end of the truss 2 with the front support 2 and the first moving support 6 temporarily fixed to the piers 13 and 12, respectively, is transferred to the second moving support 7. The truss 5 is suspended by using the suspension device 16 connected to the lower end of the truss 5 and transported to the joint portion at the front of the truss 5 to be sequentially joined by being arranged at a predetermined joint position.

In order to move the erection truss 5 forward with the erection of the precast block, FIG.
As shown in (b), on a rail 10 arranged on a bridge surface 8 of a completed span with a first moving column 6 to which a temporary fixing device 16 is connected at a lower end temporarily fixed to a pier 13. On the carriage 9 provided on the rear support 3 for traveling.

At this time, the second movable support 7 is positioned behind the truss 5 so that the second movable support 7 serves as a counterweight to prevent the rear support 3 from being lifted up and to be stable. In this state, the truss 5 can be moved.

That is, as shown in FIG. 2, the distance L2 between the position of the center of gravity (W1) of the second moving support 7 + the center of gravity (W2) of the truss 5 and the forward moving support temporarily fixed to the pier 13 is determined. Since the relationship L2> L1 occurs between the distance L1 between the front strut 2 and the front pier 14, the rear strut 3 must be kept stable without lifting when the truss 5 is moved. Can be done.

Further, as shown in FIG.
If the truss 5 is further moved to the front pier 14, the truss 5 is supported by three points of the front support 2, the first support 6 and the rear support 3, so that the second support 7 is moved in a stable state. Further, if the center of gravity (W2) of the truss 5 passes through the middle point after the first moving support 6 is fixed, the rear support 3
Can be opened, so that the rails 10 can be of the length L1 shown, which can be placed on the bridge surface 8 near the completed span pier 12.

As described above, the reaction force of the rear column 3 acts only on the pier portion, not only has little effect on the structure of the completed system, but also the rear column 3 like a conventional precast block erection apparatus. Since the reaction force of the rear strut does not act on the bridge body when traveling on the bridge surface, it is not necessary to increase the strength of the bridge body due to the erection load.

When the first moving support 6 and the second moving support 7 are pivotable and movable in the width direction of the truss 5, the moving direction of the truss 5 is changed to change the plane curved shape. Bridges can also be addressed.

[0021]

As described above, according to the present invention, when the truss is advanced, the work is simple, and the second moving support acts as a weight, and the lift generated on the rear support when moving. , And can move in a stable state.

When the truss is moved, the truss is held by a first moving column and a second moving column supported near the pier or near the pier, respectively. When traveling on the bridge surface, the rear strut does not travel over a wide area on the bridge surface, so that the load for erection is not applied to the entire bridge body, so that it is not necessary to increase the strength of the entire bridge body Not only that, the truss is always supported at or near the pier, so that the work can always be performed in a stable state.

Further, when the first moving column and the second moving column are pivotable and movable in the width direction of the truss, it is possible to cope with a flat curved bridge.

[Brief description of the drawings]

FIG. 1 is a side view showing a truss used in an embodiment of the present invention.

FIG. 2 is an illustration of the use of the embodiment of the invention shown in FIG.

FIG. 3 is an explanatory diagram showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Precast block erection apparatus 2 Front support 3 Back support 5 Truss 6 First movable support 7 Second movable support 9 Dolly 10 Rail

Claims (2)

[Claims] 1. A truss having a track extending in a longitudinal direction provided on a lower surface thereof, and a front strut and a rear strut respectively suspended at a front end and a rear end of the lower face. A first movable column mounted thereon, a second movable column suspended from a trolley suspended to be able to travel on the track, and a bogie provided on the bridge surface and provided below the rear column travels. A precast block erection device, comprising: 2. The precast block erection apparatus according to claim 1, wherein the first movable support and the second movable support are pivotable and movable in the width direction of the truss.