JP2567559B2 - Bridge construction method using precast girders - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction method for constructing a bridge using a precast member among construction methods for constructing a bridge.

[0002]

2. Description of the Related Art Conventionally, when constructing with the same construction method, wires are preliminarily stretched between the piers to be constructed, and precast girders are sequentially hung on the wires, or beams are sequentially dispatched from the existing part by hand, The construction method was to send out precast girders one by one by suspending or placing them from the temporary beams with the required bridge piers in advance.

[0003]

However, in the method of suspending from a stretched wire, the deflection of the wire becomes a problem, and in the case of a hand-stretched temporary beam, it takes time to temporarily install the beam itself.

The present invention has a form in which a precast girder is temporarily installed by means of a temporary beam, and its purpose is to shorten the time required to bridge the temporary beam between required piers.

[0005]

In order to achieve the above object, according to the present invention, a temporary beam can be attached and detached between piers via a pin provided on the temporary beam, and can be vertically swung with the pin as a fulcrum. When supporting and moving the temporary beam, the temporary beam is pivoted in the vertical direction with the pin of the bridge pier located rearward in the construction order among the piers spanning the temporary beam as the fulcrum. The pier and the pier located further rearward in the construction order of the pier will support the temporary beam with the pier, and the precast girder will be erected using the temporary beam.

In carrying out the present invention, the temporary beams may be bridged between columns that are erected near the bridge piers. Further, in order to make the turning force as small as possible, a counterweight may be attached to the turning-side fulcrum end of the temporary beam. Also, two temporary beams will be installed, one on each side of the pier.
It is advisable to connect two temporary beams so that they can rotate simultaneously. Further, the temporary beam may be made to have strength only for its own weight at the time of relocation and the minimum load required for relocation, and may be appropriately reinforced later.

[0007]

Since the transfer is performed by turning, the temporary beam can be transferred in a short time. In order to convey the precast girder using the temporary beam, one that has the function of raising and lowering the load, for example, a traveling type gate crane is run on the guide rail on the temporary beam and the precast girder is hung by the gate crane. Carry it to the desired position, suspend the precast girder, and support it directly on the temporary beam or with a bracket attached to the temporary beam.

[0008]

[Examples] An overall view during construction is shown in Figs. A bracket 2 for receiving the temporary beam 4 is provided in advance on each pier 1A, 1B, 1C. Pins 5 are provided near both ends of the temporary beam 4, and the temporary beam 4 is bridged between the piers 1A and 1B in the figure. Each bracket 2 of the pin 5 of the temporary beam 4 is fitted and supported by a U-shaped receiver 3 in which the top of each bracket 2 is cut off. However, measures such as increasing the number of fixed points will be taken depending on the load conditions.

4 and 5 schematically show a method of replacing the temporary beam 4 bridged between the bridge piers 1A and 1B between the bridge piers 1B and 1C. First, as shown in FIG. 4, the counterweight 6 is attached to the pier 1B side of the temporary beam 4. Next, as shown in FIG. 5, the temporary beam 4 is turned around the pin of the rear pier 1B in the construction order. The pin 5 on the front pier 1A side in the construction order is a U-shaped receiver 3 of the bracket 2 of the pier 1C further rearward in the construction order as the temporary beam 4 rotates.
The counterweight 6 is removed while it is fitted to.

U-shaped receiver 3 for pin 5 and bracket 2
It is preferable that the fitting portion for rotating the temporary beam 4 around the pins is provided with a stopper so that it is desirable to apply the same treatment to all the pin portions at the end of the work. Further, depending on the ability of the rotating device for rotating the temporary beam 4 around the pin and other conditions, the counterweight 6 may not be attached.

Two temporary beams 4 are provided on each side of the pier 1 as shown in FIG. 2, and each of them is relocated by the above method. You may work at the same time. In this case, the shape of the bracket 2 shown in FIG. 3 may be used depending on the strength of the connection. Moreover, the bracket 2 may be independent of the pier 1 and independent. Also,
Temporary beams should be strong enough to withstand their own weight at the time of relocation and the minimum load that acts during relocation,
You may take the method of reinforcing appropriately later.

6 and 7 show a method of transporting a precast girder by means of a temporary beam. A guide rail 7 is laid on the upper surface of the temporary beam 4, and a wheel 9 rolling on the rail 7
The precast girder 6 is hung by the winch 10 of the gate type crane 8 having the above, carried to the target position, and hung down. The suspended precast girder 6 is supported by a bracket or the like attached to the temporary beam 4. The transport device for transporting the precast girder serves the intended purpose if it is a dolly having a function of raising and lowering the load, although not shown.

[0013]

INDUSTRIAL APPLICABILITY The present invention relates to a method of constructing a bridge using precast girders, in which the transfer of the temporary beams for carrying the precast girders over the piers is carried out by using the pins of the temporary beams on the piers or columns separately provided as fulcrums. Since it is performed by turning, the time for changing the temporary beam can be greatly shortened. In addition, since the precast girder is transported by a trolley that travels on a temporary beam, there is no inconvenience due to slack of the wire as in the case of a wire stretched between piers.

[Brief description of drawings]

FIG. 1 is a side view showing construction of a bridge using a precast girder.

FIG. 2 is a view on arrow A in FIG.

FIG. 3 is a front view showing another example of the bracket.

FIG. 4 is a side view showing a method of relocating a temporary beam, which is a pre-relocation state.

5 is a side view of the temporary beam of FIG. 4 during transfer.

FIG. 6 is a front view showing a method of transporting a precast girder using a temporary beam.

FIG. 7 is a side view of FIG. 6;

[Explanation of symbols]

 1 ... Pier 2 ... Bracket 3 ... U-shaped receiver 4 ... Temporary beam 5 ... Pin 6 ... Counterweight 7 ... Guide rail 8 ... Gate crane 9 ... Wheels 10 ... Winches

Claims (1)

(57) [Claims] 1. A method for constructing a bridge using precast girders, wherein a temporary beam is bridged between bridge piers and moved on the temporary beam to build a precast girder between the piers. The piers or columns on which the temporary beams are bridged are detachably supported between the installed columns via the pins provided on the temporary beams and pivotally supported in the vertical direction with the pins as fulcrums. Among them, the temporary beam is pivoted in the vertical direction using the pin of the pier or pillar located at the rear in the construction order as the fulcrum, and the pier or pillar of the pin that became the pivot fulcrum and the pier or pillar located further behind in the construction order of the pier or pillar A method of constructing a bridge using precast girders, characterized in that a temporary beam is supported as a bridge pier or a pillar, and the precast girder is erected using the temporary beam.