KR100527797B1 - Prestressed concrete girder bridge construction method using the precast concrete segment - Google Patents

Abstract

The present invention provides a connection junction formed with a fixing hole in the end inner surface of the block-out portion formed on both the outer side and the upper surface of the end of the precast segment, which can ensure the construction property, the stability and economical of the connection portion; And a fixing device for fastening through the fixing hole and the fixing hole of another precast segment to join the connection joint of the precast segment.

Description

Construction method of PSC girder bridge using precast segment {PRESTRESSED CONCRETE GIRDER BRIDGE CONSTRUCTION METHOD USING THE PRECAST CONCRETE SEGMENT}

The present invention relates to a PSC girder bridge construction method that can be easily and economically connected to the prefabricated segment manufactured.

Patent No. 334635 (Segmental Bulb Tee Girder and Construction Method for Long-Span Bridges) has been introduced with respect to the prior art for constructing a PSC girder bridge by connecting precast segments related to the present invention.

Figure 1 shows the junction of the bulb tee girder 10, 20, a method of construction with a spliced girder is introduced.

That is, in manufacturing the girder, it is manufactured by segmenting the end segment and the center segment, and moving each girder 10 and 20 while moving from the bridge end to the center of the bridge, and forming a shear key 30 on the joint surface to prevent slippage. And to improve the shear resistance, the bonding between the bonding surface between the epoxy 40 to be bonded to each other, and to secure the epoxy bonding between the temporary tensioning material 50 between the girder abdomen is settled after tension It is introduced.

The girder 10 and 20 connected and joined as described above are provided with PC strands installed therein and fixing anchors installed at both ends thereof, so that necessary temporary prestresses are introduced.

However, in the case of the above construction method

Only epoxy bonding and shear keys are used to connect the girders, which makes it difficult to secure the structural safety of the connections. Even if a temporary tension member is used, it is only a supplement to the epoxy bonding. It could not play a big role in the union. In addition, there was a problem that the tension and settlement of the temporary tension material may be somewhat inefficient and economical.

An object of the present invention is to provide a method for constructing a PSC girder bridge using a precast segment that is structurally more stable in connection of a precast segment for a PSC girder, and can easily and economically secure the bonding performance thereof.

The present invention to achieve the above technical problem

First, connecting joints having fixing holes are formed in block-out portions formed on both outer and upper surfaces of the segment ends, that is, three surfaces, for joining the precast segment.

Steel bars penetrating the fixing holes formed in the other precast segments were installed in the fixing holes to tighten the fastening nuts so that the precast segments could be structurally connected to each other.

Second, the first prestress is introduced by tensioning and fixing the PC strand through the inside of the connected segment end so as to withstand the dead weight of the connected precast segment, thereby reducing the profile and cross-sectional size of the PSC girder. I did it.

Third, the slab is formed while the PSC girder with primary prestress is mounted between the shift and the piers, and PC strands are continuously installed and tensioned throughout the entire length of the PSC girder in addition to the external anchorages provided at the ends of the PSC girder. Secondary prestress was introduced to the entire girder by setting it up afterwards, so that it was able to resist slab load, bridge railing and common load.

BRIEF DESCRIPTION OF DRAWINGS To describe the present invention more clearly and easily, the following describes the best embodiments of the present invention in detail with reference to the accompanying drawings, and embodiments according to the present invention may be modified in various other forms, and thus the scope of the present invention. Is not limited to the embodiment described below.

2A to 2F illustrate a construction method of a PSC girder bridge using a precast segment in order, and the construction method of the PSC girder bridge is

In the connection of the precast segment for the PSC girder, a junction key 111 or an end junction 110 in which a junction key 111 and a junction groove 112 are provided in parallel; Connection joints 120 having fixing holes 122 formed in end inner surfaces of the block-out parts 121 formed on both outer and upper surfaces of the segment ends; Producing a precast segment (100) comprising; and an insertion tube (133) inserted into the fixing hole (122) positioned to face each other (s1);

After joining the precast segment 100 by the end joint 110, a steel bar 131 is installed through the insertion pipe 133, and a fastening nut 132 is formed at a screw fastening part formed at an end of the steel bar. After fastening and tightening, filling the filler 134 between the insertion pipe 133 and the steel bar 131 to connect a plurality of precast segments to each other (s2);

Manufacturing a PSC girder 700 into which primary prestress is introduced using a PC strand 200 installed in the connected precast segment (s3);

Installing the PSC girder 700 into which the primary prestress is introduced to the shift 400 or the pier 500, and then forming a slab 600 at the connection portion and the upper portion of the PSC girder (s4);

And introducing a second prestress into the PSC girder 700 by using the PC strand 300 additionally installed in the PSC girder (s5).

Steps s1 to s3 are steps for producing a PSC girder having a predetermined length in the vicinity of a factory or a site, and introducing primary prestresses, and s4 and s5 are construction steps after the manufactured PSC girder is placed. This can be seen as the step of introducing a second prestress into the PSC girder.

First, the precast segment 100 of the present invention is manufactured by segmenting into a plurality of divided segment girders in consideration of the overall length of a predetermined PSC girder, and then forming an end joint formed at an end of the divided segment girder as described below. 110, and then coupled to each other by a connection joint 120 and the fixing device 130.

FIG. 3A shows the end precast segment 100a of the precast segment 100, and FIG. 3B shows the center precast segment 100b installed between the center, i.e., between the end precast segments 100a. 3C is a cross-sectional view of the connection junction 120 of the precast segment 100.

The end precast segment (100a) is provided with a sheath tube, a conventional anchorage that can be installed after the tension of the PC strand (200) installed inside the girder for the introduction of the primary prestress at the left end.

An external fixing hole 140 is installed on the outer surface to introduce the second prestress on the outer side and is installed inside the entire length of the PSC girder 700, and the PC strand 300 that is exposed at the end is fixed after tension. do.

On the right end, a block out portion 121 is formed on three sides on both sides and the upper surface of the segment as shown in FIGS. 3A and 3C. As a result, the end precast segment 100a and the center precast segment 100b may be structurally secured by the fastening force of the fixing device 130 including the steel rod installed over three surfaces. Construction is very easy and it can be a very economical connection method.

 The block out part 121 has a plurality of fixing holes 122 for connecting the central precast segment (100b) is formed on the inner end surface, the size of the fixing device 130 is installed in the fixing hole 122, specifically What is necessary is just to form the space of the grade which can easily install the steel bar 131.

In addition, a bonding groove 112 is formed at the right end surface so that the corresponding bonding key 111 of the central precast segment 100b is inserted so that both segments can be bonded to each other.

In the case of the central precast segment 100b, as shown in FIG. 3B, the block-out part 121 is installed on both sides and the upper surface of the three surfaces, and is formed at both ends, so that the other central precast segment 100b and the end are respectively formed. The precast segment 100a and the fixing device 130 may be connected to each other.

In addition, a plurality of fixing holes 122 are formed in each of the inner end surfaces of the block-out part 121 to connect different center and end precast segments 100b and 100a.

In the present invention, it is referred to as a connection joint 120 including a fixing hole 122 in the end inner surface of the block-out portion 121 formed on both outer and upper surfaces of the segment end.

The connection unit 120 of the specific precast segment 100c and the precast segment 100d is connected to each other as shown in FIG. 4A by the fixing device 130 of the present invention.

The fixing device 130 includes an insertion tube 133 inserted into the fixing hole positioned to face each other; A steel rod 131 inserted into the insertion tube 133 and having a screwing portion formed at an end thereof; A filler 134 filled between the insertion tube 133 and the steel bar 131; And a fastening nut 132 that is fastened to the screw fastening part and joins the connection joint part 120 of both segments by tightening the steel bar 131.

Fig. 4A shows in particular the junction of the precast segment 100c and the precast segment 100d, and Figs. 4B and 4C show the fixing part provided at the junction of the precast segment 100c and the precast segment 100d. Installation cross section and AA cutaway view of the device 130.

Insertion tube 133 is a tube that is installed in communication with the fixing holes 122 formed in the segments (100c, 100d), respectively, is preferably used from the viewpoint of economics, but is not limited thereto.

Insertion tube 133 serves as an induction path through which the steel bar 131, which will be described later, can be easily penetrated, and a space for accommodating the filler 134 is formed.

The steel bar 131 has a function of a rod-shaped connecting material having a diameter smaller than that of the insertion pipe 133. The screw fastening part is formed at both ends, and is penetrated inside the insertion pipe 133 so that both ends protrude from the block-out part 121.

Both ends of the steel bar 131 are supported on the end inner surface by a washer, so that the fastening nut 132 is tightened and installed so that each girder can be stably connected to each other. This is because a large number are installed in succession.

Although not shown, in the end treatment of the steel bar 131, screw fastening parts may be formed on only one side of the steel bar 131, and the other end may be fastened by fastening nuts only on one side while the other end is formed as a fixing part. have.

The steel rods 131 and the insertion tube 133 installed are tightened to be filled with a filler 134 including mortar so that the steel rods 131 may be fixedly installed.

The precast segment 100 manufactured as described above and connected to each other is shown in FIG. 2A as step s1. The production of such precast segments 100 will usually be manufactured in a factory and made to a length that is easy to be transported to the field,

The end precast segment 100a is located at both ends, and a plurality of central precast segments 100b, which are adjustable in length, are located. In particular, in the case of the point portion, the end precast segment 100e without the external fixing hole is located.

A state in which the precast segments 100 manufactured at the factory are connected to each other in the field is illustrated in FIG. 2B as an s2 step.

The connection joint of each segment is primarily connected so as not to slide with each other by the end junction 110 including a joining groove and a joining key, and is secondly tightened by the fixing device 130 of the present invention. The connection will be more stable. In this way, the segments connected to each other are structurally connected in a very stable state, which is a very economical connection method.

As a result, the precast segments 100 connected to each other are mounted on the alternating and pier using cranes and the like. Such lifting operations require a cross-sectional size that can resist the bending moment caused by the dead load of the precast segments 100. do. If the cross-sectional size can be reduced, the PSC girder can be manufactured in the long span while forming a lower mold height.

In order to achieve this purpose, the precast segments 100 connected to each other are fabricated to resist the bending moment by introducing a first prestress through the fixing operation after the tension of the PC strand 200, thereby precast segment 100 The bending moment due to dead weight of the plurality of PCs can be made to bear most of the PC strand.

At this time, the PC strand 200 is fixed after tension at both ends of the precast segment 100 via the interior of the precast segment 100, whereby the PSC girder 700 is finally manufactured. This manufacturing step is shown in FIG. 2C as the s3 step.

The PSC girder 700 fabricated in step s3 is mounted on a shift and piers through a lifting operation, and the PSC girder 700 installed by the mounting work is illustrated in FIG. 2D as step s4.

The state in which the slab 600 is formed on the PSC girder 700 in the mounted state is also shown in FIG. 2E as the s4 step.

At this time, Figure 2e is a state in which the slab 600 is formed by continuously integrating the slab concrete, including the point portion in the state in which the PSC girder 700 is separately installed between the shift and the piers in a simple bridge installation method. In this case, instead of the slab concrete, the slab may be manufactured in a precast manner to form the whole slab while connecting the slabs to each other.

The slab 600 in the s4 step acts as a secondary dead weight that also generates a bending moment for the installed PSC girder 700, and the center separator, bridge railings, and pavement layers also act as secondary dead loads.

It is possible to design in advance with a PSC girder 700 that can resist the bending moment due to this secondary dead load, but this should eventually increase the PSC girder cross section.

Therefore, the PSC girders are mounted on the PSC girder by the PC strand 300 that is tensioned and fixed to the external anchorages installed in the end precast segments installed on the alternating side so as to resist bending moments due to common loads including secondary dead loads and traffic loads. It is shown in FIG. 2F as step s5 that the secondary prestress is introduced.

That is, the size of the cross section of the PSC girder can be designed more efficiently and smaller by the secondary prestress.

In this case, the PC strand 300 is continuously installed over the entire length of the PSC girder 700, in particular, the branch portion is installed to the upper part of the girder to be able to resist the branch portion momentum.

According to the construction method of the PSC girder of the present invention, the production, connection, transport and construction of the precast segment manufactured by division can be performed very economically, and the structural stability can be ensured, which is very competitive in manufacturing the PSC girder bridge. It can be a bridge construction method.

1 shows a junction of a conventional PSC girder.

2A, 2B, 2C, 2D, 2E and 2F show the construction sequence of the PSC girder according to the present invention.

3A, 3B and 3C show cross-sectional views of the precast segment and connection joint of the present invention.

4A, 4B and 4C show the connection state diagram of the precast segment of the present invention, the installation cross section of the fixing device and the A-A cut section.

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

100: precast segment

100a, 100b: end precast segment, center precast segment

121: block out portion 122: fixing hole

130: fixing device 131: steel bar

132: tightening nut 133: insertion tube

134: Filler

200,300: PC strand 400,500: Shift, pier

600: slab 700: PSC girder of the present invention

Claims (5)

delete In connection of a precast segment for a PSC girder, the precast segment A connection joint including a connection joint surface in which fixing holes are formed in an end inner surface of each block-out portion formed on both outer and upper surfaces of the segment end; And a fixing device configured to join the connection joint of the precast segment while being tightened through the fixing hole of the other precast segment with the fixing hole. The fixing device may include an insertion tube inserted into a fixing hole positioned to face each other; A steel rod inserted into the insertion tube and having a screw connection portion formed at an end thereof; Filling material filled between the insertion tube and the steel bar; And a fastening nut fastened to the fastening part to tighten the steel bar to join the connection joints of both girders. A precast segment is formed at the end of the precast segment is formed an end junction formed by connecting a junction key or a junction key and a junction groove. delete In connection of precast segment for PSC girder, An end junction in which a junction key or a junction key and a junction groove are provided; A connection joint having a fixing hole formed in an end inner surface of each block-out portion formed on both outer and upper surfaces of the segment end; And a insertion tube inserted into the fixing hole positioned to face each other. After joining the precast segment by the end joining portion, the rod is penetrated to the insertion tube, and the fastening nut is fastened and tightened to the screw fastening portion formed at the end of the steel rod, and then a filler is inserted between the insertion tube and the steel rod. PCC girder bridge construction method comprising the; connecting the plurality of precast segments to each other by charging. 5. The method of claim 4, further comprising: fabricating a PSC girder into which primary prestresses are introduced using a PC strand installed in the connected precast segment; Installing a PSC girder in which the primary prestress is introduced at an alternating or pier, and then forming a slab at an upper portion of the connection and the upper portion of the PSC girder; And further introducing a second prestress into the PSC girder by using the PC strand added to the PSC girder.