JP2002356814A - Construction method of bridge pc floor slab - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a construction method of a bridge PC floor slab capable of carrying out split construction for reducing a construction period for the construction method providing bridge axial prestress on the bridge PC floor slab in e.g. expressway, motorway or the like when it is constructed on a main girder erected between piers. SOLUTION: The construction method of the bridge PC floor slab 1 constructed on the main girder by fitting the longitudinal direction of the floor slab in the direction at right angles to the bridge axis to neighbor the direction of the bridge axis is so constituted that the PC floor slab 1 is divided to construct and that the bridge axial prestress is provided every divided PC floor slab divided body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a precast PC for a bridge, for example, on an expressway or a motorway.
The present invention relates to a construction method for applying prestress in the bridge axis direction when laying on a main spar erected between piers on a floor slab.

[0002]

2. Description of the Related Art Conventionally, as a construction method of laying a precast PC (prestressed concrete, the same applies hereinafter) floor slab for a bridge, as shown in FIGS. The precast PC slab 1 pre-stressed in the longitudinal direction of the slab by a cable made of a PC steel material or a PC stranded wire at a factory is set in the longitudinal direction of the PC slab 1 in a direction b perpendicular to the bridge axis. Laying on
After laying the required number of pieces along the bridge axis direction a,
At the site, a PC cable such as a PC steel strand is inserted into the sheath, one end is fixed, and the other end is tightened and fixed with a jack or the like, so that the PC floor slab is prestressed. are doing.

After the PC slab 1 is laid, a grout material such as ultra-rapid hardened concrete is provided on a box-opening portion of the PC slab which is located at a portion where the dowel is erected for joining with the steel main girder 5. To combine the PC floor slab 1 and the steel main girder 5. A method of finishing by asphalt pavement or the like on a PC floor slab is known.

[0004]

However, the above P
In the replacement work of the C slab 1, traffic regulation is performed, so short-term construction is desired. However, prestressing in the bridge axis direction a is performed in units of blocks between the piers 19 or all PC slabs for the entire length of the bridge. Since it is performed over a period of time, partial construction is difficult and large-scale repair work is required, and the construction period is prolonged. Further, when two lanes are changed at the same time, there is an inconvenience that the traffic regulation is completely closed. The construction method of the bridge PC floor slab according to the present invention is proposed to solve such a problem.

[0005]

SUMMARY OF THE INVENTION A bridge PC according to the present invention
The gist for solving the above-mentioned problem of the method of constructing a slab is to construct a PC slab for a bridge to be laid adjacent to the main girder in the direction of the bridge axis so that the longitudinal direction of the slab is perpendicular to the bridge axis. The method is a method of dividing and laying the PC slab to be laid, and applying a prestress in the bridge axis direction to each of the divided PC slabs.

[0006] The PC slab has a size equivalent to one lane, and a joint between the divided PC slabs is formed by joining opposite ends of prestressing cables by a coupler. Is included.

According to the method for constructing a bridge PC slab according to the present invention, the PC slab can be replaced for each divided, for example, about two to three PC slabs. In addition, if the size of the PC floor slab is one lane, traffic can be restricted on only one side and the PC slab can alternately pass on the remaining one side lane. Furthermore,
A coupler can be used for joining the divided PC floor slabs.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a method for constructing a bridge PC slab according to the present invention will be described with reference to the drawings. As shown in FIG. 1 and FIG. 2, a strand 2 of a PC steel strand is inserted into a buried sheath 3 in a longitudinal direction at a factory, and fixed and fixed at one end thereof, and is fixed at the other end thereof. It is formed by filling the grout material into the inner space of the sheath after fixing with a fixing nut 4 after tensioning with a jack, and a prestressed PC floor slab 1 is mounted on a steel main girder erected between fulcrums. Lay on top of 5.

The PC slab 1 is laid with its longitudinal direction along a direction b perpendicular to the bridge axis, and a plurality of boxless portions 6 provided on the PC slab 1 are connected to the steel main girder 5. Are laid in such a manner as to correspond to the positions of the dowels erected on the upper surface.

In this case, as shown in FIGS. 4 and 5,
The height of the PC floor slab 1 is adjusted. A nut 9 is fixed to a predetermined position on the upper surface of the flange 5a of the steel main girder 5 in advance by welding means. A screw bolt dowel 12 fitted with an adjustment nut 10 and a washer 11 is screwed to the nut 9. Stand up.

[0011] With the boxed portion 6 of the PC floor slab 1 corresponding to the position of the dowel 12, a through hole provided in an L-shaped level adjusting plate 13 embedded in the PC floor slab 1. The PC floor slab 1 is placed so that the dowel 12 is inserted into the (slightly large fool hole).

The height is positioned by the adjusting nut 10, the washer 14 is fitted into the dowel 12 from above, and the fixing nut 15 is fastened to position. Then, the non-shrink mortar 16 is placed between the flange 5a and the PC slab 1
The space filled by the seal rubber 17 is filled.

Further, as shown in FIG. 5, for example, three PC slabs are laid continuously in the bridge axis direction a. At the joint of the adjacent PC floor slabs 1 and 1, as shown in FIG.
The sealing rubber 7 is interposed.

After the laying of the three PC slabs 1 is completed, the PC slabs 1 are connected to the sheaths 1a, 1a, 1a buried in the bridge axis direction a of the PC slab 1 so that the PC cables (P
A strand of C steel strand) 18 is inserted through each of them.

One end of the PC cable 18, for example,
In FIG. 5, the left end is fixed first, and FIG.
As shown in (1), the condominium 18a having a thread groove formed on the outer peripheral surface at the other end on the right side is tensioned by the jack by taking a reaction force with the anchor plate 1c and fixed by the fixing nut 19. Thereby, prestress is introduced in the bridge axis direction a using the three PC slabs 1 as one divided body.

Thereafter, the following three divided members of the PC slab 1 are laid in the bridge axis direction a in the same manner as described above. As shown in FIGS. 7 (A) and 7 (B), the coupling is performed using a coupler 20 having a thread groove formed on the inner peripheral surface.

As shown in FIG. 7B, a wedge-shaped adjusting ring 22 and an adjusting nut 21 are attached to an apartment 18a of the PC cable 18, and a cylindrical coupler 20 is fitted therein. It is connected. Even if the axis of the PC cables 18 is slightly displaced, such as left and right displacement in the horizontal plane and vertical displacement, the coupler 20 is automatically adjusted by the adjustable nut 21 so that the coupler 20 can be easily connected. Can be done.

More specifically, in the state shown in FIG. 7A, the coupler 20 is attached to the apartment 18a projecting from the end face of the left PC floor slab 1 to which the prestress has already been introduced.
The mansion 18a of the PC cable 18 is protruded from the sheath 1a of the right PC floor slab 1 where prestress is to be introduced, and is connected to the coupler 20. Then, the PC cable 18 is tightened with a jack on the right end side of the right PC floor slab.
Thereafter, the fixing nuts 19 are tightened at both left and right ends of the right PC floor slab to fix and tension.

As another method, one end of the PC cable 18 is fixed with a fixing nut 19 at the right end of the PC floor slab to which prestress is to be introduced. At the left end of the PC floor slab, the other end of the PC cable 18 is tensioned by a jack and fixed by a fixing nut 19. After that, connect both PC floor slabs with coupler 20,
By tightening the adjustment ring 22 with the coupler,
A constant tension may be applied to the divided PC slabs.

At the connecting portion of the connecting recess 1b of the PC floor slab 1, after the prestress is introduced in the bridge axis direction a, the condominium 18a and the coupler 20 are protected by, for example, a cylindrical protection provided with cuts in the longitudinal direction. Material (not shown)
Cover with.

After the prestress in the bridge axis direction a of the divided body of the PC slab 1 is introduced, the boxed portion 6 (FIG. 3 and FIG. A grout material such as a non-shrink mortar 8 is filled in the joint portion (see FIG. 7), the joint portion (see FIG. 7), and the joint portion (see FIG. 6).

Asphalt is paved on the PC slab 1 after the completion of the laying. The asphalt may be paved every time one PC slab is completed, or a plurality of PCs may be paved. Paving may be performed after the floor slabs are connected. Thereby, the laying work of the PC floor slab 1 and the asphalt pavement work can be performed simultaneously in a single-push type at the same time, and rapid construction can be performed.

Also, as described above, during one span or one
When a large number of PC slabs in a section are divided and constructed, for example, into about 2 to 4 pieces, when replacing the PC slab, repair work is performed for each divided PC slab. This makes it possible to shorten the period of traffic regulation on expressways, motorways, and the like where short-term construction is particularly required.

Further, when replacing a certain PC slab divided body, even if the prestress of the PC slab divided body is released, in the adjacent PC slab divided body which is not replaced, the fixing nut 19 is replaced. Because I am nervous and established
The existing state is maintained without releasing the prestress of the PC floor slab that is not replaced.

In another embodiment of the present invention, the PC slab 1
With the size of one lane. In other words, the length of the PC floor slab 1 in the longitudinal direction is set to one side lane, so that in the case of rebuilding, the remaining one side lane can be used to allow one-side traffic without blocking the entire road. It is. Further, in order to connect the PC floor slabs 1 for the one lane after the replacement in the direction perpendicular to the bridge axis, the coupler 20 shown in FIG. 7 is used, so that the action of the coupler 20 in the bridge axis direction is achieved. In the same manner as described above, even if there is a slight displacement in the horizontal plane and a displacement in the vertical direction, they can be easily connected.

[0026]

As described above, the method of constructing a PC slab for a bridge according to the present invention is to lay the main slab adjacent to the bridge axis in the longitudinal direction of the slab in a direction perpendicular to the bridge axis. A method for constructing a PC floor slab for a bridge, comprising:
Since the C slab is divided and laid, and prestressing in the bridge axis direction is applied to each divided PC slab,
Asphalt pavement work can be performed in parallel with the work of laying C slabs, which not only shortens the construction period, but also allows for partial construction when replacing PC slabs, thus reducing traffic regulations. It has an excellent effect of being able to do so.

Since the PC slab has a size equivalent to one lane, it has an excellent effect that the replacement work of the PC slab can be performed without stopping the traffic on the entire surface.

[Brief description of the drawings]

FIG. 1 is an explanatory view in a method for constructing a bridge PC slab according to the present invention.

FIG. 2 is an explanatory view in a method for constructing a bridge PC slab according to the present invention.

FIG. 3 is an explanatory view of a composite portion of the PC slab and the steel main girder in the method for constructing a bridge PC slab according to the present invention.

FIG. 4 is an explanatory view of a composite part of the PC slab and the steel main girder in the method for constructing a bridge PC slab according to the present invention.

FIG. 5 is an explanatory view in plan view of the method for constructing a bridge PC floor slab according to the present invention.

FIG. 6 is an explanatory diagram of a joint portion between PC slabs in the method for constructing a bridge PC slab according to the present invention.

FIG. 7 is an explanatory view of a connecting portion between PC floor slabs in the method for constructing a bridge PC slab according to the present invention.

FIG. 8 is an explanatory view showing a method of constructing a bridge PC slab according to a conventional example.

[Explanation of symbols]

1 PC slab, 1a sheath, 1b connection recess, 1c
Anchor plate, 2 strands, 3 sheaths, 4
Fixing nut, 5 steel main girder, 5a flange, 6
Boxless part, 7 Seal rubber, 8 Non-shrink mortar, 9
Nut, 10 adjustment nut, 11 washer, 12
Giver, 13 level adjustment plate, 14 washer, 15
Fixing nut, 16 Non-shrink mortar, 17 Seal rubber, 18 PC cable, 18a Mansion, 19
Fixing nut, 20 coupler, 21 adjustable nut, 2
2 Adjustment ring.

Continued on the front page (72) Inventor Hiroshi Kawada 6-3-1, Nishi-Shinjuku, Shinjuku-ku, Tokyo F-term (reference) 2D059 AA14 AA41 CC03 GG55

Claims (3)

[Claims] 1. A method for constructing a PC floor slab for a bridge, which is laid on a main girder adjacently in the bridge axis direction with the longitudinal direction of the floor slab aligned in the direction perpendicular to the bridge axis, wherein the PC floor to be laid is provided. A method of constructing a PC floor slab for a bridge, comprising dividing and laying a slab, and applying prestress in a bridge axis direction to each of the divided PC slabs. 2. The method according to claim 1, wherein the PC slab has a size corresponding to one lane. 3. The bridge PC according to claim 1, wherein the ends of the divided prestressed cables are joined by a coupler at a joint portion between the divided PC floor slabs. Construction method of floor slab.