KR20130001459A - Bulk head for precast box girder mould - Google Patents

Abstract

PURPOSE: A bulk head for a precast box girder form is provided to reduce the use of strands for manufacturing a precast box girder and to reduce the manufacturing time of the precast box girder. CONSTITUTION: A bulk head(10) for a precast box girder form comprises a bulk head(10) and a guide roll device(20). A pair of protective walls is attached to the outer surfaces of the top ends of side plates of the bulk head. Hinges for suspending the guide roll device are installed on the top ends of the protective walls. The guide roll device is installed on the top ends of the side plates of the bulk head, and the top end thereof is suspended in the hinges.

Description

Bulk head for precast box girder formwork {BULK HEAD FOR PRECAST BOX GIRDER MOULD}

The present invention relates to a bulkhead for forming an end of a box girder by assembling it at both ends of a formwork for manufacturing a precast box girder, and in particular, a bulk for precast box girder formwork focusing on reducing the stranded wire and shortening the manufacturing air of the box girder. It's about the head.

Conventionally, as illustrated in FIG. 1, in the precast box girder manufacturing site, the bulk heads 2 are assembled at both ends of the formwork 1, and in this state, a plurality of stranded wires 3 are mounted on the reinforcing bar network loaded on the formwork 1. ), And then both ends of each of the strands (3) through the bulk head (2) mounted on both ends of the formwork (1), and both ends of each of the strands (3) to pass through the holding up device (4) After the end of all strands 3 exposed to the outside of the holding-up device 4 is bitten by the wedge of the reaction table 5, and tensioned to correspond to the design value, prestress is applied, concrete is poured and cured to manufacture box girders. In the portion of the stranded wire placed between the holding-up device 4 and the reaction table 5, the portion 6 close to the holding-up device 4 is cut in such a manner as to cut the gas cutting machine.

Both sides of the bulk head are symmetrical in shape, and a line of holes for passing ductility is drilled in the upper left and right side plates of the bulk head. Lecturers are the same number as the Lecturers, and all of them are in and out. When the strand that penetrates the raised strand hole is stretched horizontally, bending occurs in the strand at the outer edge of the strand strand. The neglecting of the stranded ships causes deformation of the bulkhead of the stranded ships as well as the side plates of the bulkheads around the stranded ships, and damages the stranded wires in contact with the stranded ships.

The holding-up device minimizes the friction between the strands and the strands when the tension lines are pulled out through the strands of the bulkhead, while inducing the ends of the strands facing the reaction zone to be curved smoothly without bending at sharp angles. Spacer end spacers to protect the bends of the strands and to allow the strands to be tensioned more effectively by settingtle on the reaction zones so that the ends of the strands are horizontal with the reaction zones, and to allow individual strands to wedge into the reaction zones at regular intervals. It is to play a role.

However, in the precast box girder formwork, if the holding girders are installed between the bulkhead and the reaction zone, the box girders are made longer than necessary to expose the strands to the outside of the bulkhead. This means that the use of stranded wire is excessive, and the excessive use of the stranded wire leads to an increase in the manufacturing cost of the box girder, which increases the production cost per box girder, and the installation of the holding up device and the hanging of the stranded wire at the holding place is the manufacture of the box girder. It can also cause air delays and reduce the manufacturing efficiency of the box girders.

It is an object of the present invention to provide a bulkhead for precast box girder formwork which can contribute to the reduction of the strand for producing precast box girder and the improvement of manufacturing efficiency according to the shortening of the box girder manufacturing air.

These tasks are based on the assumption that a conventional bulkhead is assembled at both ends of the precast box girder formwork with a plurality of stranded holes drilled at the upper ends of both side plates, and the stranded vessels are located outside the stranded vessels and penetrate the stranded vessels. A bulkhead for precast box girder formwork can be achieved by installing a guide roll device for a stranded ship that guides the end portion of the end portion to be curved and directed toward the reaction force.

As the guide roll device replacing the conventional holding up device is accommodated in the bulk head, the distance between the bulk head and the reaction force band is shortened. This means shortening of the strand. Given the tens of strands per precast box girder, the savings in the strands are enormous. As a result, the manufacturing cost of the precast box girder is greatly reduced.

In addition, it is necessary to install a separate holding-up device and apply a large number of stranded wires to it, but using the bulk head of the present invention, the guide roll device as the end of the stranded wires passes through the stranded wire drilled in the side plate. Since it is spread over each roll of the roll, it is easy to fix the end of the strand to the reaction zone, and correspondingly, the manufacturing time of the precast box girder is shortened.

1 is a conceptual diagram of a conventional precast box girder manufacturing apparatus
2 is a front view of the bulk head according to the present invention;
3 is a perspective view of a protective wall of the bulkhead to which the guide roll device is to be seated;
4 is a perspective view of the guide roll device
5 is a conceptual diagram of a box girder manufacturing apparatus applied a bulk head of the present invention
6 is a longitudinal cross-sectional side view of the protective wall in FIG.
Figure 7 is an illustration of a portion of the strand extending through the steel wire hole of the bulk head over the roll of the guide roll device;

In Figure 2, the bulkhead 10 for precast box girder formwork proposed in the present invention is provided with a guide roll device 20 in the upper end of the side plate (11). That is, the guide roll device 20 is guided to the reaction force over the end portions of the stranded line penetrating into the stranded line hole from the die side to the upper end of both side plates 11 of the bulkhead 10 where the stranded line is located.

Referring to FIG. 3, a pair of protective walls 12 are attached to the upper end portions of both side plates 11 of the bulk head 10 to prevent the guide roll device 20 from flowing sideways of the bulk head 10. The top 13 of these protective walls 12 is provided with a hinge 13 for installing the guide roll device 20 in a hinged manner, the hinge shaft 14 is inserted into the hinge 13.

When tensioning the strand on the reaction force side to impart prestress to the precast box girder, minor deviations in the lateral direction may occur between the strand of the bulkhead 10 and the tension of the reaction force side strand. This deviation mainly occurs when the guide roll of the guide roll device 20 located between the wedge of the reaction zone and the bulkhead side strand ball is not positioned on the line connecting the strand ball and the wedge in a straight line. At this time, if the guide roll device 20 does not show the movement corresponding to the deviation when the tension line is tensioned from the reaction force side, the hinge rod 14 and the handle 13 as well as the suspension rod 26 of the guide roll device 20. There is a fear that the force is applied to deform or deform or the position of the guide roll device 20 becomes unstable, thereby causing a problem in the guide line function.

The handle 13 has a suspension rod 26 attached to the top of the guide roll device 20 hingedly installed and trapped in the protective wall 12, although the guide roll device 20 receives a flow restriction in the lateral direction. It is a supporting means for the guide roll device necessary to give a clearance for turning in the lateral direction within a given tolerance range between the inner surface of the protective wall 12 and the outer surface of the roll base 21 of the guide roll device 20. The handle 13 is attached in parallel with the width direction of the bulk head 10.

In Fig. 4, the guide roll device 20 is a roll shaft in which the rotatable roll 22 traverses the roll stand 21 in a horizontal and vertical direction to the comb-shaped roll stand 21 arranged at regular intervals in the transverse direction. The roll stand 21 is installed so as to be idling on the 23, and the roll stand 21 is held in engagement with the roll stand support plate 24 by a horizontal pin 25 that penetrates the upper end portion in the width direction of the bulk head 10.

A suspension rod 26 is attached to the center of the roll base support plate 24. The suspension rod 26 is an element necessary for attaching the guide roll device 20 to the hinge shaft 14 of the handle 13, which is a vertical rod, and the hinge shaft 14 is parallel to the handle 13 at the upper end thereof. A hinge-shaped suspension plate 27 having a perforated hinge shaft hole for installation is attached thereto.

FIG. 5 shows that the bulk head 10 provided with the guide roll device 20 is normally mounted at both ends of the box girder formwork, and the ends of all the strands 3 arranged in the box girder formwork are each lectured in the bulk head 10. The state of being removed by the piercing and then biting by the reaction table 5 separately covering each roll 22 of the guide roll apparatus 20 is illustrated.

As long as the holding up device is excluded, the reaction table 5 can be placed closer to the bulk head 10. Accordingly, the length of the strand can be designed shorter than before, thereby reducing the strand. Considering that tens of strands of strands are usually installed in the box girders, the reduction of the strands is very large. And after the box girder is completed, the cutting position of the end of the strand line is a portion close to the guide roll apparatus 20 among the portions of the strand line spanned between the reaction table 5 and the guide roll apparatus 20.

In FIG. 6, the guide roll device 20 is seated between the protective walls 12 of the bulk head 10 and the shaft hole of the suspension plate 27 is aligned with the shaft hole of the hinge 13 and then the hinge shaft 14 is moved. When plugged in and fixed, the guide roll device 20 can be easily installed in the bulk head 10. Each roll 22 is aligned to the outside of the steel ball 15 located in the upper end of the side plate of the bulk head 10.

In FIG. 7, the ends of the strands 30 penetrating through the strand wire holes 15 of the bulk head 10 on the formwork 40 are caught by the reaction zone and fixed by the reaction zone. In the strand 30 extending over the apex portion of the bulkhead 10, the portion of the strand area of the bulkhead 10 side should not be in contact with the inner circumferential surface of the strand line 15 and the edge thereof. 15) beneficial to the protection. In principle, the guide roll device 20 is installed in consideration of this point.

10: bulkhead
11: sidewall
12: protective wall
13: stone
20: guide roll device
21: roll stand
22: roll
27: placard

Claims (2)

A pair of protective walls 12 are side by side attached to the outer surface of the upper end of both side plates 11 of the bulkhead 10 in which the stranded ship is located, and the bulkhead is provided with a guide roll device suspension 13 on the top of the protective wall 12. And a bulkhead for precast box girder formwork, comprising a guide roll device for hanging strands hinged to the top 13 with a saddle in the protective wall 12. The method of claim 1,
The guide roll device 20 is formed on the roll shaft 23 in which the rotatable roll 22 crosses the roll stand 21 in a horizontal and vertical direction to the comb-shaped roll stand 21 arranged at regular intervals in the transverse direction. The roll stand 21 is installed to be idle, and the state of engagement with the roll stand support plate 24 is maintained by the horizontal pin 25 penetrating its upper end portion in the width direction of the bulk head 10. Bulkhead for precast box girder formwork with a suspension rod 26 attached to the top with a dowel-type suspension plate 27 at the center.

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