KR200300029Y1 - Multi-span Continuous Preflex Composite Beam Having Part for Fixing Tendon - Google Patents

Abstract

The present invention is concrete and P. C. wrapping steel I-girder and lower flange. Combining the strands, P.C. with one end or both ends pre-drawn from the upper surface of the lower flange concrete. A composite beam for assembling a strand to allow tensile fixation after slab concrete and abdominal concrete are cast, wherein the drawn beam is drawn. The present invention relates to a multi-span continuous preplex composite beam having a new anchoring structure capable of firmly fixing the stranded wire, thereby further improving the continuity of the beam.

In the present invention, each preflex beam 1 is fabricated independently from the ground by combining the steel type I girder 2 and the lower flange concrete 3, and then each of the above-mentioned pier 6 over a plurality of spans. It is a multi-span preflex composite beam that completes and connects the slab concrete 10 and the abdominal concrete 11 after the beam 1 is installed. The upper flange 2a and the abdomen 2b of the steel I-type girder 2 of the two beams 1 adjacent in the direction are successively joined by the upper joint plate 7a and the abdominal joint plate 7b; In the lower flange concrete (3) below the lower flange (2c) of the steel I-type girder (2). The strand 4 is disposed, and a through hole 14 is formed in the lower flange 2c to form the P. An end of the strand 4 is drawn out of the lower flange concrete 3 through the through hole 14 at the beginning of the parent section of the inner point; The through flange 14 is formed in the upper flange (2a), the P. C. drawn out to the lower flange concrete (3). The strand 4 is drawn out through the through hole 14 onto the upper flange 2a; Steel wire fixing holes 8 are formed at the rear of the through hole 14 of the upper flange 2a, respectively, and are drawn out onto the upper flange 2a. A strand 4 intersects so as to overlap each other on the upper joint plate 7a of the parent section so that its end is positioned through the line anchorage 8 of the opposite steel I-girder 2; The slab concrete (10) and the abdominal concrete (11) is placed through the steel wire anchorage (8) in a state in which the casting cured successively over a plurality of spans. A multi-span continuous preplex composite beam is provided, which is characterized in that the strand 4 is tensioned and fixed to the wire anchorage 8.

In the present invention, P. C. exposed to the upper surface of the upper flange (2a). The strand 4 is not directly settled at the connecting portion, but is settled in a state where they cross each other by a predetermined length past the connecting portion, so that the connecting portion P. The strand 4 is overlapped to a predetermined length to increase the strength of the connecting portion, P. The compressive stress acting on the slab concrete 10 is doubled by the tension and fixation of the strand 4, so that the continuity of the beam becomes more excellent.

Description

Multi-span Continuous Preflex Composite Beam Having Part for Fixing Tendon

The present invention is directed to a multi-span continuous preplex composite beam, which will be described in more detail. The concrete and P. C. surrounding the steel I-girder and the lower flange. Combining the strands, P.C. with one end or both ends pre-drawn from the upper surface of the lower flange concrete. A composite beam for assembling a strand to allow tensile fixation after slab concrete and abdominal concrete are cast, wherein the drawn beam is drawn. The present invention relates to a multi-span continuous preplex composite beam having a new anchoring structure capable of firmly fixing the stranded wire, thereby further improving the continuity of the beam.

1A to 1D show side and front views sequentially illustrating a method of introducing prestressed compressive stress to a lower flange concrete by combining conventional steel I type girder 2 and reinforced concrete. The schematic manufacturing process of the preplex composite beam or leafrestrest preplex composite beam 1 using the following is as follows.

First, a steel I-type girder 2 having a horizontal upper flange 2a, a lower flange 2c and a vertical abdomen (WEB) 2b is manufactured to be curved upward as shown in FIG. 1A. . In this state of applying a load Pf to the steel I-girder 2 in the curved state to induce a deflection deformation bent downward as shown in FIG. 1B, the steel I-girder 2 as shown in FIG. 1C. After pouring the lower flange concrete (3) of the shape surrounding the lower flange (2c) of the curing (curing), remove the load (Pf) applied to the steel I-type girder (2). As a result, the deflection deformation, which was curved downward, is returned to its original state, and at this time, the lower flange concrete 3 surrounding the lower flange 2c of the steel I-type girder 2 moves together with the steel I-type girder 2. Thus, the prestressed compressive stress is introduced into the lower flange concrete 3. Prefabricated composite beam 1 is produced by this method.

On the other hand, P. C. in advance in the cross section of the lower flange concrete (3) of the preplex composite beam (1). After arranging the strand 4, the pre-stressed compressive stress was first introduced into the lower flange concrete 3 by the manufacturing process of the preflex composite beam 1 as described above. By tension-fixing the strand 4, a prestressed compressive stress can be further introduced and manufactured, and what is produced by this method is called the leafrest preplex composite beam 1.

In the case of installing the above-described preflex composite beam 1 on a bridge or alternating bridge in a multi-span bridge, the beam 1 of each longitudinally adjacent beam is not continuous and the simple structure system is repeated over each span. At this point, it is inevitably required to install the expansion joint of the bridge at the point which is the boundary of each span, which not only decreases the driving performance of the vehicle but also requires a lot of effort and cost for the continuous maintenance of the expansion joint.

Therefore, it is necessary to allow the above-described preplex composite beam 1 to be completely integrally connected.

The present invention was developed to solve the desperately required matters of the conventional preplex composite beam as described above. Seed. The present invention is to provide a multi-span continuous preplex composite beam having a fixing structure capable of continually fixing the strands to further fix the continuity of the composite beam.

1A to 1D are side and front views sequentially illustrating a method of introducing prestressed compressive stress into lower flange concrete by combining conventional steel I-girder and reinforced concrete;

Figure 2 is a side cross-sectional view of the bridge by the three-span continuous preplex composite beam according to the present invention,

3 is an enlarged side cross-sectional view of two beams longitudinally adjacent above the mid-point pier of FIG.

4A to 4C are cross-sectional views taken along line A-A, line B-B, and line C-C of FIG. 3, respectively. Is a cross-sectional view showing the arrangement of the strands,

5 is a partially cutaway perspective view of a composite beam used for the first span and the last span, which are outer spans, as a composite beam according to the present invention;

6 is a partially cutaway perspective view of the composite beam used in the inner span according to the present invention,

FIG. 7 is an enlarged perspective view of a connection portion of two beams longitudinally adjacent to the inner point pier of FIG. 2;

FIG. 8 is a longitudinal sectional view of the upper flange and the abdomen of the two beams of steel I-girder longitudinally adjacent over the mid-point pier of FIG.

<Description of the symbols for the main parts of the drawings>

1-preflex composite beam, 1a-outer span beam,

1b-beam outside girth, 2-steel I-girder,

2a-upper flange, 2b-abdomen,

2c-lower flange, 3-lower flange concrete,

4-Mr. P. Strand (P.C. strand) 5-shift,

6-pier, 7a-upper flanged joint plate,

7b-abdominal joint, 8-liner anchorage,

9-fixed mounting plate, 10-slab concrete,

11-abdominal concrete, 12-tension opening of slab concrete,

13-bolt, 14-through hole for steel I-girder,

15-through-holes of steel wire anchorage.

The multi-span continuous preplex composite beam according to the present invention for realizing the technical purpose as described above is a combination of the steel I-girder and the lower flange concrete to manufacture each preflex beam independently on the ground In a multi-span preflex composite beam that installs each beam over a bridge over a span and completes and connects slab concrete and abdominal concrete, the two longitudinally adjacent beams in the parent section over each pier at the inner point. The upper flange and the abdomen of the steel type I girder are continuously joined by the upper joint plate and the abdominal joint plate; P. C. in the lower flange concrete under the lower flange of the steel I-girder. The strand 4 is disposed, and a through hole is formed in the lower flange to form the p. An end of the strand is drawn out of the lower flange concrete through the through hole at the beginning of the parent section of the inner point; Through holes are formed in the upper flange, the P. C. drawn out to the lower flange concrete. The strand is drawn out onto the upper flange through the through hole; Steel wire anchorages are formed behind the through-holes of the upper flange, respectively, and are drawn out to the upper flange. Strands are crossed so that they overlap each other on the upper joint plate of the parent section so that their ends are positioned through the steel anchorage of the opposite steel I-girder; The P. C. positioned through the wire anchorage in a state in which slab concrete and abdominal concrete are continuously cast and cured over a plurality of spans. It is characterized by being settled in the steel wire anchorage by tensioning the strand.

The present invention will be described in detail with reference to the accompanying drawings.

In the combined beam 1 according to the present invention, in combining the steel I-girder 2 and the lower flange concrete 3, the lower flange below the lower flange 2c of the steel I-girder 2 Many P. seeds in concrete (3). The strand 4 is disposed, and a through hole 14 is formed in the lower flange 2c to form the P. One or both ends of the strand 4 are pulled out from the upper surface of the lower concrete 3 through the through hole 14, and the steel type I girder 2 caused in the manufacturing process of the conventional preflex beam 1 is carried out. The primary prestress compressive stress is introduced into the lower concrete 3 as a displacement of.

Subsequently, each beam 1 is independently hypothesized on the alternation 5 or the pier 6 of each span as shown in FIG. 2, but the beam 1a of the outer span, which is the last span of the first span, as shown in FIG. 5 and FIG. Produced by dividing the beam (1b) between the center inner diameter as shown.

Next, the steel I type girders 2 as shown in FIGS. 7 and 8 are arranged so that the longitudinally adjacent two beams 1 of the two beams 1 are continuous on each of the piers 6 at the boundary points of the respective spans. Two beams (1) longitudinally adjacent by welding or bolting (13) by installing two layers of abdominal joint plate (7b) and upper joint plate (7a) on the upper flange (2a) and the abdomen (2b) of the The abdomen 2b and the upper flange 2a of the steel I-type girder 2 are completely continuous. At this time, the abdominal joint plate (7b) may be provided with a vertical reinforcement in order to directly transfer the vertical load of the point portion from the steel I-girder (2).

When the continuous coupling of the steel I-type girder 2 as described above is completed, the blood exposed outside from the upper surface of the lower concrete (3) of the two longitudinally adjacent beams as shown in Figs. 3, 4 and 7 .Seed. Each end of the strand 4 passes through the upper flange 2a of the steel I-type girder 2, and is assembled so as to cross each other on the upper surface of the upper flange 2a. To this end, each of the upper and lower flanges (2a) and the lower flange (2c). A through hole 14 that can penetrate the strand 4 should be drilled in advance.

P. C. withdrawn to the upper surface of the upper flange (2a) as above. The strands 4 cross each other over the upper joint plate 7a, and then end portions thereof are respectively fixed at the upper flanges 2a of the opposite girder.

To this end, a steel wire anchorage 8 is formed on the upper surface of the upper flange 2a of the girder to the rear of the through hole 14 on the upper flange 2a. A plurality of through holes 15 through which the strand 4 is formed are formed.

P. C. was drawn to the upper surface of the upper flange (2a) and then crossed over the upper joint plate (7a). The strand 4 is inserted into the through hole 15 of the wire anchorage 8 and then exposed to the outside of the wire anchorage 8.

Steel I-girder 2 and P. C. of two adjacent beams 1 at each point on the pier 6 as described above. When the continuous assembly of the strand 4 is completed, the abdomen and the slab concrete (10) (11) is poured continuously to form an integral structure over each span. At this time, in the upper part of the girder 2 to the installation position of the steel wire anchorage 8, a tension opening 12 is not provided in which the slab concrete 10 is not poured. This will be described later. This is to tension and settle the strand 4.

When the abdomen and the slab concrete (10) (11) is cured to a predetermined strength or more, the P. C cross each other on the upper joint plate (7a) and its ends exposed outside the through hole 15 of the steel wire anchorage (8). . The strand 4 is sequentially tensioned and then fixed to the liner anchorage 8.

As such, in the present invention, P. C. exposed to the upper surface of the upper flange 2a. The strand 4 is not directly settled at the connecting portion, but is settled in a state where they cross each other by a predetermined length past the connecting portion, so that the connecting portion P. The strand 4 is overlapped to a predetermined length to increase the strength of the connecting portion, in particular P. The compressive stress acting on the slab concrete 10 is doubled by the tension and fixation of the strand 4, so that the continuity of the beam becomes more excellent.

Mr. P. After the tension and fixation of the strand 4 is completed, the tension opening 12 may be filled with concrete or cement mortar to be finished.

So far, steel I type girders 2 and P. C. of two adjacent beams 1 on each pier 6 corresponding to the inner point. Continuous coupling and tension settling of the strand 4 is described above, P. C. withdrawn to the alternating side 5, which is an outer point. Each end of the strand 4 is not fixed to the upper surface of the upper flange (2a) as shown in Figure 5, a separate fixing provided in the middle of the abdomen (2b) of the steel I-type girder (2) at the point above the shift (5) It is fixed by the fixing plate 9 to be embedded in the abdominal concrete (11).

According to the present invention, steel I-girder 2, reinforced concrete (3) (10) (11) and P. C. By properly combining the strand 4, as shown in FIG. 2, the steel I-girder 2 inside the concrete (3) (10) and (11) is completely continuously coupled to each other as shown in FIG. Since the prestressed compressive stress caused by the strand 4 is continuously introduced over a plurality of spans so as to naturally cross and resist the center positive moment section and the point parent moment section, the same as in the conventional preflex beam 1 As the displacement of the steel type I girder (2) caused during the manufacturing process, the first compression prestress stress is first introduced into the lower flange concrete (3) of the beam (1), so that the weight of the beam (1) and the abdominal and slab concrete (10) Resisting the dead weight of (11), and at the point of the boundary of each span, the parent moment generated in the steel I-girder (2) when placing the abdomen and slab concrete (10) (11) is the point of the steel I-girder (2) The connection part effectively resists the positive moment of the middle part of the earth due to the live load and the parent moment of the point slab concrete (10). It effectively responds to the secondary prestressed compressive stress due to the tension settling of the strand 4, thereby eliminating the use of the expansion joint of the bridge, and further increasing the length of the ground length as compared to the conventional preflex composite bridge. It is effective to construct multi-span continuous preplex composite beam of continuous and safe continuous system.

In particular, in the present invention, P. C. exposed to the upper surface of the upper flange (2a). The strand 4 is not directly settled at the connecting portion, but is settled in a state where they cross each other by a predetermined length past the connecting portion, so that the connecting portion P. The strand 4 is overlapped to a predetermined length to increase the strength of the connecting portion, P. The compressive stress acting on the slab concrete 10 is doubled by the tension and fixation of the strand 4, so that the continuity of the beam becomes more excellent.

Claims (1)

Combined steel I-girder (2) and lower flange concrete (3) to make each preplex beam (1) independently from the ground and then to each beam (1) over the piers (6) over multiple spans As a multi-span preflex composite beam for connecting the slab concrete 10 and the abdominal concrete 11 after the installation and integrally connected, The upper flange 2a and the abdomen 2b of the steel I-type girder 2 of two beams 1 longitudinally adjacent in the parent section section on each pier 6 of the inner point are connected to the upper joint plate 7a. And are continuously joined by the abdominal joint plate 7b; In the lower flange concrete (3) below the lower flange (2c) of the steel I-type girder (2). The strand 4 is disposed, and a through hole 14 is formed in the lower flange 2c to form the P. An end of the strand 4 is drawn out of the lower flange concrete 3 through the through hole 14 at the beginning of the parent section of the inner point; The through flange 14 is formed in the upper flange (2a), the P. C. drawn out to the lower flange concrete (3). The strand 4 is drawn out through the through hole 14 onto the upper flange 2a; Steel wire fixing holes 8 are formed at the rear of the through hole 14 of the upper flange 2a, respectively, and are drawn out onto the upper flange 2a. A strand 4 intersects so as to overlap each other on the upper joint plate 7a of the parent section so that its end is positioned through the line anchorage 8 of the opposite steel I-girder 2; The slab concrete (10) and the abdominal concrete (11) is placed through the steel wire anchorage (8) in a state in which the casting cured successively over a plurality of spans. A multi-span continuous preplex composite beam, characterized in that the strand 4 is tensioned and fixed to the steel anchorage 8.