KR102695874B1 - Spliced girder and method of manufacturing same - Google Patents

Abstract

A spliced girder according to one embodiment of the disclosed invention may include a first segment having primary tendons arranged on each of an upper flange and a lower flange, a second segment arranged on one side of the first segment, a connecting portion configured to connect the first segment and the second segment, and a second tendon arranged to penetrate the first segment and the second segment and configured to be tensioned after the primary tendon is tensioned.

Description

{Spliced girder and method of manufacturing same}

The present invention relates to a spliced girder and a method for manufacturing the same, and more particularly, to a spliced girder capable of precisely controlling displacement deviation of a girder such as discontinuous sagging through divided tension, and a method for manufacturing the same.

PSC I-girder is one of the girders with excellent structural efficiency, economy, and constructability. It was mainly used for spans of 30 m to 35 m according to road construction standards. However, recently, an improved PSC girder with a Bulb-T cross-section has been developed and is being used for long spans of approximately 60 m.

However, the cross-section of these long-span PSC girders becomes larger in order to place anchors and gantry devices at the ends. As the span length increases, there is a risk of cracks occurring in the area where the cross-section becomes smaller due to the difference in dead weight between the center and ends.

Recently, in order to apply these PSC I-type girders to long spans, a spliced girder is being used, in which the girders are divided, manufactured into segments at a factory, and then the joints are formed on site and connected with steel wires.

However, these spliced girders have a problem in that the camber values generated differ depending on the split location and the prestress force introduced into the girder, resulting in discontinuous deflection (locked in deflection) in which the deflection angle between segments at the connection is different.

In addition, when applying PSC I-type girders composed of multiple segments to long spans of 50 m or more, there are many connections with a high risk of defects, the ratio of span length (L) to girder height (H) and span length (L) to width (B) increases, and the rigidity of the girder decreases, causing deformations such as sweep and camber to occur more significantly than with general PSC girders.

These numerous joints and excessive deformations cause abnormal stress and defects in the girder, and the girder may tip over during transport and installation. In addition, when the floor slab is poured after the girder is installed, additional stress occurs due to the increase in the thickness of the floor slab, which reduces the safety of the bridge.

(Patent Document 0001) Republic of Korea Publication Patent No. 10-2009-0048054 (Long-span PSC Girder Bridge Construction Method Using Post-tension Method)

Therefore, a spliced girder and a manufacturing method thereof according to one embodiment of the disclosed invention are inventions created to solve the above-described problems, and more specifically, a spliced girder and a manufacturing method thereof can be provided that can stably prevent over-sprung by manufacturing the girder in a split tension manner at a manufacturing site rather than manufacturing the girder at piers and abutments.

In addition, a spliced girder and a method for manufacturing the same according to one embodiment of the disclosed invention can provide a spliced girder and a method for manufacturing the same capable of suppressing lateral bending and rotational displacement of the girder by arranging tendons symmetrically about the center of the girder and simultaneously tensioning them.

In addition, a spliced girder and a method for manufacturing the same according to one embodiment of the disclosed invention can provide a spliced girder and a method for manufacturing the same capable of suppressing lateral bending and rotational displacement of a girder by using a support plate and a guide portion.

A spliced girder according to one embodiment of the disclosed invention may include a first segment having primary tendons arranged on each of an upper flange and a lower flange, a second segment arranged on one side of the first segment, a connecting portion configured to connect the first segment and the second segment, and a second tendon arranged to penetrate the first segment, the connecting portion, and the second segment and configured to be tensioned after the primary tendon is tensioned.

The above connection part can be formed by pouring concrete.

The above primary tension members may include upper tension members arranged in a pair symmetrically on the upper flange of the first segment, and lower tension members arranged in a pair symmetrically on the lower flange of the first segment.

The above pair of tension members can be tensioned simultaneously.

The above-mentioned tension members may be composed of single unbonded mono strands.

A method for manufacturing a spliced girder according to one embodiment of the disclosed invention may include the steps of installing a support plate, arranging a first segment on an upper portion of the support plate, arranging and tensioning a primary tendon on each of an upper flange and a lower flange of the first segment, arranging a second segment on one side of the first segment, forming a connecting portion connecting the first segment and the second segment, and inserting and tensioning a secondary tendon so as to penetrate the first segment, the connecting portion, and the second segment.

The above connection part can be formed by pouring concrete.

A spliced girder and a method for manufacturing the same according to one embodiment of the disclosed invention have the advantage of suppressing cracks and stably preventing over-bulging by manufacturing the girder in a split tension manner at a manufacturing site rather than manufacturing the girder at piers and abutments.

In addition, the spliced girder and the method for manufacturing the same according to one embodiment of the disclosed invention have the advantage of being able to suppress lateral bending and rotational displacement of the girder by arranging tendons symmetrically about the center of the girder and simultaneously tensioning them.

In addition, the spliced girder and the manufacturing method thereof according to one embodiment of the disclosed invention have the advantage of suppressing lateral bending and rotational displacement of the girder by using a support plate and a guide portion, and minimizing downward deflection of the girder support portion.

Figure 1 is a drawing showing a girder bridge in which discontinuous sagging occurs according to conventional technology.
FIG. 2 is a drawing illustrating a spliced girder and a fabrication plant according to one embodiment of the disclosed invention.
Figure 3 is a top view of the spliced girder and fabrication site shown in Figure 2.
FIG. 4 is a drawing illustrating a step of installing a support plate in a manufacturing site in a method for manufacturing a spliced girder according to one embodiment of the disclosed invention.
FIG. 5 is a drawing illustrating a step of arranging a first segment in a method for manufacturing a spliced girder according to one embodiment of the disclosed invention.
FIG. 6 is a drawing illustrating a step of tensioning a first tension member of a first segment in a method for manufacturing a spliced girder according to one embodiment of the disclosed invention.
FIG. 7 is a cross-sectional view illustrating a first tension member arranged in a first segment in a method for manufacturing a spliced girder according to one embodiment of the disclosed invention.
FIG. 8 is a drawing illustrating a step of arranging a second segment in a method for manufacturing a spliced girder according to one embodiment of the disclosed invention.
FIG. 9 is a drawing illustrating a step of arranging reinforcing bars or sheath pipes at a connecting portion in a method for manufacturing a spliced girder according to one embodiment of the disclosed invention.
FIG. 10 is a drawing illustrating a step of forming a connecting portion and tensioning a secondary tension member in a method for manufacturing a spliced girder according to one embodiment of the disclosed invention.
FIG. 11 is a drawing illustrating a guide part installed to prevent lateral bending of a girder when tensioning a tendon in a method for manufacturing a spliced girder according to one embodiment of the disclosed invention.
FIGS. 12 and 13 are drawings illustrating steps of mounting a spliced girder manufactured in a manufacturing plant on an abutment and a pier according to a method for manufacturing a spliced girder according to one embodiment of the disclosed invention.
FIG. 14 is a flowchart illustrating a method for manufacturing a spliced girder according to one embodiment of the disclosed invention.

The embodiments described in this specification and the configurations illustrated in the drawings are merely preferred examples of the disclosed invention, and there may be various modified examples that can replace the embodiments and drawings of this specification at the time of filing of the present application.

Additionally, the same reference numbers or symbols presented in each drawing of this specification represent parts or components that perform substantially the same function.

In addition, the terminology used in this specification is used for the purpose of describing embodiments, and is not intended to limit and/or restrict the disclosed invention. The singular expression includes the plural expression unless the context clearly indicates otherwise.

In this specification, terms such as “include” or “have” are intended to specify the presence of a feature, number, step, operation, component, part or combination thereof described in the specification, but do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

Additionally, terms including ordinal numbers such as “first,” “second,” etc., used herein may be used to describe various components, but the components are not limited by the terms, and the terms are used only for the purpose of distinguishing one component from another.

For example, without departing from the scope of the present invention, the first component could be referred to as the second component, and similarly, the second component could also be referred to as the first component. The term "and/or" includes any combination of a plurality of related listed items or any item among a plurality of related listed items.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the attached drawings.

Figure 1 is a drawing showing a girder bridge in which discontinuous sagging occurs according to conventional technology.

Referring to Fig. 1, the pre-stress tension of a spliced girder bridge according to the prior art can be introduced by applying a load balancing method so that it can appropriately resist loads applied to the girder, such as self-weight, slab load, pavement and live load.

However, when applying this design method, the camber value is formed differently depending on the split location of the girder and the frist force introduced to the girder.

Therefore, as illustrated in Fig. 1, a bridge using a spliced girder according to the prior art includes a plurality of connecting portions, and there is a problem that discontinuous deflection (locked in deflection) occurs in which the deflection angles between segments are formed differently in these connecting portions.

In order to overcome this problem of discontinuous deflection, methods such as the deflection balancing method that controls the amount of prestress have been proposed. However, in reality, it is difficult to set the position of the connection at a position where the deflection angle is balanced, and even if the position of the connection and the position where the deflection angle is balanced are formed theoretically the same, concrete is not a perfectly elastic body, so the theoretical camber value and the actual camber value are different, making it difficult to completely overcome the discontinuous deflection that occurs in reality.

Therefore, the spliced girder and the manufacturing method thereof according to one embodiment of the disclosed invention can provide a safe spliced girder that can minimize deformation of the girder while having a minimum number of connecting parts in the bridge market where spans are gradually becoming longer. Details regarding this will be described later.

FIG. 2 is a drawing illustrating a spliced girder and a fabrication site according to one embodiment of the disclosed invention. FIG. 3 is a drawing illustrating the spliced girder and fabrication site illustrated in FIG. 2 from above.

Referring to FIGS. 2 and 3, a spliced girder (100) according to one embodiment of the disclosed invention may include a first segment (110) and a second segment (120).

Specifically, a spliced girder (100) according to one embodiment of the disclosed invention may be formed as an I-shaped girder, and the first segment (110) and the second segment (120) constituting the spliced girder (100) may also be formed as an I-shaped girder having a cross section having an I shape.

More specifically, the first segment (110) may be positioned at the center of a spliced girder (100) according to one embodiment of the disclosed invention.

Additionally, the second segment (120) may be placed on one side of the first segment (110).

For example, the second segment (120) may be composed of two and placed on both sides of the first segment (110).

Accordingly, the connecting portion (130) configured to connect the first segment (110) and the second segment (120) may be configured in two pieces.

More specifically, the connecting portion (130) can be formed by pouring concrete. Specifically, the connecting portion (130) can be formed by pouring concrete on site with the reinforcing bars and the sheath pipe arranged.

Additionally, the spliced girder (100) according to one embodiment of the disclosed invention can be tensioned in two stages.

For example, a spliced girder (100) according to one embodiment of the disclosed invention can be manufactured by sequentially going through a first tensioning step of tensioning a first tendon (140) arranged in a first segment (110) and a second tensioning step of tensioning a second tendon (150) arranged through the first segment (110), the connecting portion (130), and the second segment (120).

In addition, a spliced girder (100) according to one embodiment of the disclosed invention can be manufactured in a manufacturing plant while being supported on a support plate (200), and then installed on an abutment and a pier.

Accordingly, when introducing tension to the first segment (110) of the spliced girder (100), it is possible to introduce tension less than the self-weight of the first segment (110). Details regarding this will be described later.

Additionally, the spliced girder (100) according to one embodiment of the disclosed invention may be supported by a support plate (200) having a width wider than the transverse width of the spliced girder (100).

In addition, the support plate (200) can be manufactured from high-strength concrete or steel, and the downward sagging and rotational displacement of the support portion of the spliced girder (100) can be suppressed through the support plate (200).

Details regarding a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention will be described later.

A spliced girder (100) according to the disclosed invention can be configured by dividing one span into two or three segments.

For example, FIGS. 2 and 3 illustrate a spliced girder (100) configured by dividing one span into three segments.

However, the spliced girder (100) according to the disclosed invention can also be implemented as a spliced girder configured by dividing one span into two segments, as shown in (b) of FIG. 4 described later.

Below, the process of manufacturing a spliced girder (100) according to one embodiment of the disclosed invention will be described step by step.

FIG. 4 is a drawing illustrating a step of installing a support plate (200) in a manufacturing site in a method for manufacturing a spliced girder according to an embodiment of the disclosed invention. FIG. 5 is a drawing illustrating a step of arranging a first segment in a method for manufacturing a spliced girder according to an embodiment of the disclosed invention. FIG. 6 is a drawing illustrating a step of tensioning a first tendon of a first segment in a method for manufacturing a spliced girder according to an embodiment of the disclosed invention. FIG. 7 is a cross-sectional view illustrating a first tendon arranged in a first segment in a method for manufacturing a spliced girder according to an embodiment of the disclosed invention. FIG. 8 is a drawing illustrating a step of arranging a second segment in a method for manufacturing a spliced girder according to an embodiment of the disclosed invention. FIG. 9 is a drawing illustrating a step of arranging a reinforcing bar or a sheath pipe in a connecting portion (130) in a method for manufacturing a spliced girder according to an embodiment of the disclosed invention. FIG. 10 is a drawing illustrating a step of forming a connecting portion (130) and tensioning a secondary tendon in a method for manufacturing a spliced girder according to one embodiment of the disclosed invention. FIG. 11 is a drawing illustrating a guide portion (300) installed to prevent lateral bending of a girder when tensioning a tendon in a method for manufacturing a spliced girder according to one embodiment of the disclosed invention.

Referring to FIG. 4, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step of installing a support plate (200) in a manufacturing site.

More specifically, referring to (a) of FIG. 4, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step of installing a support plate (200) and a guide part (300) that support a spliced girder (100) including a first segment (110) disposed in the center and second segments (120) disposed on one side and the other side respectively along the longitudinal direction of the first segment (110).

Specifically, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention as illustrated in (a) of FIG. 4 may include a step of installing a support plate (200) that supports the lower end of the girder, and installing a guide portion (300) at a location where a connecting portion (130) connecting a first segment (110) and a second segment (120) is arranged.

In addition, referring to (b) of FIG. 4, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step of installing a support plate (200) and a guide part (300) that support a spliced girder (100) including a first segment (110) and a second segment (120) arranged on one side along the longitudinal direction of the first segment (110).

Specifically, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention as illustrated in (b) of FIG. 4 may include a step of installing a support plate (200) that supports the lower end of the girder, and installing a guide portion (300) at a location where a connecting portion (130) connecting a first segment (110) and a second segment (120) is arranged.

However, the position and number of the guide portion (300) are not limited thereto, and the guide portion (300) may be positioned at the lower center of the first segment or the lower center of the second segment (120) to prevent lateral displacement of each segment.

In addition, the installation time of the guide portion (300) according to the disclosed invention may be different from the installation time of the support plate (200).

For example, the guide member (300) may be installed on the support plate (200) just before the primary tension member (140) is tensioned or just before the secondary tension member (150) is tensioned. Details regarding this will be described later.

Referring to FIG. 5, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step of arranging a first segment (110) on top of a support plate (200).

For example, referring to (a) of FIG. 5, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step of arranging a first segment (110) at the center of a support plate (200) to manufacture a spliced girder (100) composed of three segments.

Also, referring to (b) of FIG. 5, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step of arranging a first segment (110) on one side of a support plate (200) to manufacture a spliced girder (100) composed of two segments.

Referring to FIG. 6 (a) and (b), a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step of tensioning a primary tension member (140) of a first segment (110).

More specifically, as illustrated in FIG. 7, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step of arranging and tensioning a primary tension member (140) on each of an upper flange and a lower flange of a first segment (110).

More specifically, the first segment (110) of the spliced girder (100) of the disclosed invention may have primary tension members (140) arranged on each of the upper flange and the lower flange.

At this time, the primary tension member (140) may include an upper tension member (141) arranged in a left-right symmetrical pair on the upper flange of the first segment (110) and a lower tension member (142) arranged in a left-right symmetrical pair on the lower flange of the first segment (110).

In addition, according to a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention, a pair of upper tension members (141) can be tensioned simultaneously, and a pair of lower tension members (142) can be tensioned simultaneously.

Additionally, a pair of tension members (141) may be composed of single unbonded mono strands.

Additionally, the lower tension member (142) of one upper section may be composed of a post-tension type steel wire.

More specifically, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention can enable the tension force by the lower tendon (142) to have a smaller value than the tension force by the upper tendon (141) and the sagging load by the self-weight of the first segment (110).

Specifically, the tension force by the primary tension member (140) of the spliced girder (100) according to one embodiment of the disclosed invention can be defined as in Equation (1) below.

Equation (1):

( = Span length when tense, = Ha-yeon's tension, = Ha Yeon's tension from the city center to the eccentricity, = The tension of the performance tension, = From the center of the tension of the performance to the eccentricity, = self-weight)

Therefore, according to the method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention, the tension of the first segment (110) is tensioned to an amount less than its own weight, and the upper tendons (141) and the lower tendons (142) are arranged symmetrically on both sides and tensioned simultaneously, thereby controlling over-swelling, lateral displacement, and displacement of joints that may occur when the segments are tensioned.

Accordingly, the spliced girder (100) according to one embodiment of the disclosed invention has the effect of suppressing discontinuous deflection (locked in deflection) by preventing upward camber from occurring, and can have the function of suppressing lateral curvature and over-swelling of the entire girder and preventing cracks when the secondary tendon (150) is tensioned later.

Referring to FIG. 8 (a) and (b), a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step of arranging a second segment on an upper surface of a support plate (200).

More specifically, referring to (a) of FIG. 8, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step of manufacturing a spliced girder (100) composed of three segments by arranging second segments (120) on one side and the other side of a first segment (110).

In addition, referring to (b) of FIG. 8, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step of manufacturing a spliced girder (100) composed of two segments by arranging a second segment (120) on one side of a first segment (110).

Additionally, referring to (a) and (b) of FIG. 9, the second segment (120) may include a reinforcing bar, reinforcing bar mesh, or sheath pipe arranged in a space formed between the first segment (110).

Through this, when the connecting portion (130) is later poured with concrete, a reinforcing bar, reinforcing bar mesh, or sheath pipe can be built into the inside of the connecting portion (130), and the ductility of the connecting portion (130) can be increased.

Referring to FIG. 10 (a) and (b), a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step of forming a connecting portion (130) connecting a first segment (110) and a second segment (120) by pouring concrete, and tensioning a secondary tension member (150).

More specifically, the secondary tension member (150) may be composed of a connecting steel wire inserted into the girder so as to penetrate the first segment (110), the connecting portion (130), and the second segment (120).

Additionally, referring to FIG. 11, the guide member (300) can be installed on the support plate (200) just before tensioning the secondary tension member (150).

More specifically, the guide portion (300) may be configured as a pair of projection shapes that protrude upward from the support plate (200) to support both sides of the girder.

Through the configuration of this guide member (300), the lateral displacement of the girder due to the tension of the secondary tension member (150) can be suppressed.

Specifically, the guide section (300) can be placed at the center of the girder or at the connection section (130) of each segment, and is formed and installed as a steel frame, so that there is a technical effect of suppressing the lateral bending of the girder when the tendon is tensioned.

Therefore, the spliced girder (100) according to one embodiment of the disclosed invention introduces tension in the field in a post-tension manner, performs the first tension with a size less than its own weight using the first tendon (140), and performs the second tension to the entire girder using the second tendon (150), thereby reducing the tension of the second tendon (150) and minimizing lateral displacement due to tension, which has a technical effect.

In addition, the disclosed invention has a technical effect of minimizing sagging and rotational displacement of a support portion by installing a support plate (200) made of high-strength concrete or steel and having a width wider than the width of the girder.

In addition, the disclosed invention has a technical effect of suppressing lateral displacement that may occur when a segment is tensioned by using a guide part (300) installed on a support plate (200) to support both sides of the girder.

FIGS. 12 and 13 are drawings illustrating steps of mounting a spliced girder manufactured in a manufacturing plant on an abutment and a pier according to a method for manufacturing a spliced girder according to one embodiment of the disclosed invention.

Referring to FIGS. 12 and 13, a spliced girder (100) manufactured separately in a manufacturing plant according to a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention can be installed on a pier and abutment using a separate lifting device.

For example, as illustrated in FIG. 12, a spliced girder (100) according to one embodiment of the disclosed invention may be composed of three segments, and such spliced girder (100) may be lifted alternately and pier-wise by a lifting device.

Additionally, as illustrated in FIG. 13, a spliced girder (100) according to one embodiment of the disclosed invention may be composed of two segments, and such spliced girder (100) may be alternately lifted and lifted by a lifting device.

Accordingly, the disclosed invention is not a girder manufactured from piers and abutments, but is manufactured in a separate manufacturing plant installed on the ground and then lifted, so that the tension force when tensioning the tendons can be implemented to a size smaller than the self-weight of the segment or girder, thereby having the technical effect of preventing over-sprung, lateral bending, and discontinuous sagging of the girder.

FIG. 14 is a flowchart illustrating a method for manufacturing a spliced girder according to one embodiment of the disclosed invention.

Referring to FIG. 14, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step (S110) of installing a support plate (200) in a girder manufacturing facility.

Thereafter, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step (S120) of placing a first segment (110) on a support plate (200).

Thereafter, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step (S130) of tensioning a first tension member of a first segment (110).

Specifically, the step (S130) of tensioning the first tension member of the first segment (110) may include the step of tensioning a pair of upper tension members (141) arranged symmetrically left and right on the upper flange of the girder and the step of tensioning a pair of lower tension members (142) arranged symmetrically left and right on the lower flange of the girder.

At this time, the tension of the upper tension member (141) and the lower tension member (142) can be designed to have a value smaller than the self-weight of the girder.

Thereafter, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step (S140) of arranging a second segment (120) on a support plate (200) and forming a connecting portion (130).

More specifically, the connecting portion (130) can be formed by pouring concrete.

Thereafter, a method for manufacturing a spliced girder (100) according to one embodiment of the disclosed invention may include a step (S150) of tensioning a second tension member penetrating the first segment (110), the connecting portion (130), and the second segment (120).

A spliced girder and a method for manufacturing the same according to one embodiment of the disclosed invention have the advantage of stably preventing over-sprung by manufacturing the girder in a split tension manner at a manufacturing site rather than manufacturing the girder from piers and abutments.

In addition, the spliced girder and the method for manufacturing the same according to one embodiment of the disclosed invention have the advantage of being able to suppress lateral bending and rotational displacement of the girder by arranging tendons symmetrically about the center of the girder and simultaneously tensioning them.

In addition, the spliced girder and the manufacturing method thereof according to one embodiment of the disclosed invention have the advantage of suppressing lateral bending and rotational displacement of the girder by using a support plate and a guide portion, and minimizing downward deflection of the girder support portion.

Although the embodiments have been described above by way of limited examples and drawings, those skilled in the art can make various modifications and variations from the above description. For example, appropriate results can be achieved even if the described techniques are performed in a different order from the described method, and/or components of the described system, structure, device, circuit, etc. are combined or combined in a different form from the described method, or are replaced or substituted by other components or equivalents. Therefore, other implementations, other embodiments, and equivalents of the claims also fall within the scope of the claims described below.

100; spliced girder
110; 1st segment
120; 2nd segment
130; connection
140; 1st tension
141; Performance tension
142; Ha Yeon tension
150; 2nd tension
200; Support plate
300; Guide Department

Claims (7)

A first segment having primary tension members arranged on each of the upper flange and the lower flange;
A second segment arranged on one side of the first segment;
A connecting portion configured to connect the first segment and the second segment; and
A second tension member is disposed to penetrate the first segment and the connecting portion and the second segment and is configured to be tensioned after the first tension member is tensioned;
The above primary tension member includes an upper tension member arranged in a pair of left-right symmetry on the upper flange of the first segment and a lower tension member arranged in a pair of left-right symmetry on the lower flange of the first segment.
The tension force by the lower tension member has a smaller value than the sum of the tension force by the upper tension member and the sagging load by the self-weight of the first segment.
A spliced girder characterized in that the first tendon is tensioned at the fabrication site, and after the second segment is installed and the connecting member is cast, the second tendon is tensioned at the fabrication site. In the first paragraph,
A spliced girder characterized in that the above connecting part is formed by pouring concrete. delete In the first paragraph,
A spliced girder characterized in that the pair of lower tension members are tensioned simultaneously. In the first paragraph,
A spliced girder characterized in that the above-mentioned tension members are composed of single unbonded mono strands. Steps to install the support plate;
A step of placing a first segment on the upper part of the above support plate;
A step of placing and tensioning primary tension members on each of the upper flange and lower flange of the first segment;
A step of placing a second segment on one side of the first segment;
A step of forming a connecting portion connecting the first segment and the second segment; and
A step of inserting and tensioning a second tension member so as to penetrate the first segment, the connecting portion, and the second segment;
The above primary tension member includes an upper tension member arranged in a pair of left-right symmetry on the upper flange of the first segment and a lower tension member arranged in a pair of left-right symmetry on the lower flange of the first segment.
The tension force by the lower tension member has a smaller value than the sum of the tension force by the upper tension member and the sagging load by the self-weight of the first segment.
Characterized in that the first tension member is tensioned at the manufacturing site, and after the second segment is installed and the connecting member is cast, the second tension member is tensioned at the manufacturing site.
Method for manufacturing a spliced girder. In Article 6,
A method for manufacturing a spliced girder, characterized in that the above-mentioned connecting part is formed by pouring concrete.