JP2005139613A - Continuous girder bridge supported by jacket pier - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a continuous girder bridge supported by a jacket pier, advantageous in theory of structures, and superior in workability. <P>SOLUTION: An inter-multi-diameter continuous girder bridge 3 is formed by rigidly joining a continuous girder 1 and the pier 2. In the continuous girder bridge, the pier 2 is supported by a pier foundation 8 for fixing a skeleton structure 5 for connecting a large number of steel members 4 to the water bottom ground 7 by a plurality of steel pipe piles 6, and the jacket pier 2a constituted by uplifting a plurality of leg bodies 9 at an interval in the bridge axis direction from the upper end of this pier foundation 8, that is, the jacket pier characterized by rigidly joining an upper part of the leg bodies 9 to a bridge girder support part 10 of the continuous girder 1. The leg bodies 9 are fixed to the bridge beam support part by upwardly extending the steel pipe piles 6 for fixing the skeleton structure 5 from the upper end of the pier foundation 8. A means for fixing an upper part of the leg bodies 9 to the bridge girder support part, is fixed by filling concrete 12 by inserting the upper part of the leg bodies 9 into a fixing space part 13 for opening a bottom surface arranged in the bridge girder support part 10. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a relatively large continuous girder bridge supported by a jacket pier, and more particularly to a continuous girder bridge characterized by a pier fixing part structure.

  The structure of the continuous girder bridge is because it has fewer expansion joints than the simple girder, so it can reduce vibration and noise when driving on the road, and it can be economically advantageous because the girder height can be lowered. In terms of dynamics, a simple girder has a static structure, whereas a continuous girder has a static structure, and a negative bending moment is generated at the intermediate fulcrum.

  The bridge piers that support the bridge girder, which is the superstructure of the bridge, are generally provided with footings made of reinforced concrete on the top of the caisson foundation, steel pipe pile foundation or steel pipe sheet pile foundation (multi-column foundation), and have an oval or circular cross section. Many piers are set up to support the bridge girder, but more and more large bridges use jacket-type piers.

  Because the jacket pier is a structure in which steel pipes and steel members are connected to each other, manufactured in a factory or onshore yard, transported and installed on site, and then steel pipe piles are placed and fixed and supported. In addition to being able to perform good quality control of the structure, it has the advantage of shortening the period of on-site work, and is also excellent in horizontal strength and earthquake resistance structurally.

  As a specific example of the jacket pier, a jacket pier 20 applied to an underwater foundation structure as shown in FIG. 11 is known (see, for example, Patent Document 1). A jacket pier 20 shown in FIG. 11 is provided with a jacket structure 22 in which a plurality of cylindrical (steel pipe) guide members 21 are connected to the ground, and a pile 24 is driven through the guide member 21. A bridge pier 26 is raised above a steel plate footing 25 provided on an upper part of a jacket-type underwater base 23 formed by connecting 21 and a continuous girder 1 is placed and supported.

  In addition, the support structure of the pier including the jacket pier 20 that supports the continuous girder 1 is normally a hinge support, a movable support, or a vibration-damping / isolation support using laminated rubber. Support forms are also emerging.

Moreover, in the case of the conventional support structure, as shown in FIG. 10, the intermediate support of the continuous digit 1 (bridge girder supporting portion 10), since a large negative bending moment -M ₂ occurs, girders especially continuous girder side There is a need for a member design in which a high-rigidity material is disposed, such as increasing the plate thickness of the support member. For this reason, the intermediate support part of the continuous girder 1 generally has a large cross section made of a highly rigid material having a thick plate thickness. In some cases, the height of the bridge girder 27 is changed to be high. . Therefore, in order to make this portion a compact and economical structure, it is desired to reduce the large negative bending moment −M ₂ generated in the intermediate support portion.
JP 2002-364004 A

  The pier 20 using the jacket-type underwater foundation 23 of the prior art has a structure in which a steel plate footing 25 is provided on an upper part of a jacket structure 22 in which a plurality of guide members 21 are connected, and the pier is raised above the pier 20. Therefore, it has a complicated configuration, many members are used, and the construction is complicated.

Further, the continuous column 1 near bridge leg portions for fixing the bridge girder 1, there is a problem that a large negative bending moment indicated by reference numeral -M ₂ in FIG. 10 occurs.
An object of the present invention is to provide a continuous girder bridge that is supported by a jacket pier that is advantageous in terms of structural mechanics and has excellent workability.

The present invention is summarized as the following configurations as means for achieving the object.
In the continuous girder bridge supported by the jacket pier of the first invention, in the multi-span continuous girder bridge (3) in which the continuous girder (1) and the pier (2) are rigidly connected, the pier (2) includes a number of steel members ( 4) The pier foundation (8) in which the frame structure (5) connected to the pier foundation (8) is fixed by a plurality of steel pipe piles (6), and the upper end of this pier foundation (8) is spaced apart in the direction of the bridge axis. A jacket pier (2a) constructed by raising a plurality of legs (9), and the upper part of the legs (9) is rigidly connected to the bridge girder support (10) of the continuous girder (1) It is characterized by that.

  Moreover, like the 2nd invention, the said leg (9) extends the steel pipe pile (6) which fixes frame structure (5) upward from the upper end of a pier foundation (8), and fixes it to a bridge girder support part. Is desirable.

Further, as in the third aspect of the invention, the means for fixing the upper portion of the leg (9) to the bridge girder support portion is provided with a leg in the fixing space portion (13) having an open bottom surface provided in the bridge girder support portion (10). It is better to insert the upper part of the body (9) and fill and fix the concrete (12).

According to the present invention, a bridge pier that supports a bridge girder of a continuous girder type bridge structure that is advantageous in terms of structural mechanics is excellent in quality control, can shorten the construction period, and has excellent horizontal proof strength and earthquake resistance. In addition, in the bridge pier support part of the continuous girder, it is generated in the pier part by being rigidly coupled and supported by a plurality of legs that are raised from the upper end of the jacket-type pier foundation at intervals in the bridge axis direction. The magnitude of the negative bending moment can be reduced, and the cross-section of the continuous girder pier support can be made compact. As a result, the weight of the bridge superstructure can be reduced.
In addition, since the pier support part of the pier and the continuous girder is rigidly connected with concrete, there is no need for the conventional anti-lifting measures against the negative bending moment in the heel support, and no heel is used. It is an economical structure that does not require maintenance.
In addition, the fixing means for the jacket pier and continuous girder pier support part of the present invention can absorb the construction error in which the upper part of the leg raised from the upper end of the jacket type pier foundation is provided in the continuous girder pier support part. Since it is inserted into a fixing space of a large size and filled with concrete, the continuous girder can be easily fixed to the legs of the installed jacket pier.

Embodiments of the present invention will be described below.
1 is an overall side view of a three-span continuous girder bridge supported by a jacket pier according to an embodiment of the present invention, FIG. 2 is a side view showing a part of the jacket pier and a continuous girder support portion, and FIG. 4 is a plan view taken along the line AA of FIG. 2, FIG. 4 is a cross-sectional view taken along the line BB of FIG. 3 (cross-sectional view perpendicular to the bridge axis), and FIG. FIG. 6 is a partially cutaway perspective view showing the fixing structure between the internal structure of the continuous girder support and the upper leg of the bridge pier, and FIG. 7 is a partially enlarged view of the leg fixing space shown in FIG. 8 and 8 are plan views taken along the line CC of FIG.

  In the present invention, as shown in FIG. 1, a continuous girder 1 between two or more spans (three spans in the illustrated embodiment) consisting of main girders such as a girder and a box girder having a floor slab 28 on the upper surface, This is a continuous girder bridge having a structure in which a bridge girder support portion 10 of a continuous girder 1 is supported by a plurality of legs 9 raised from a jacket-type pier foundation 8 at intervals in the bridge axis direction.

  As shown in FIG. 2 and FIG. 4 or FIG. 6, the jacket pier 2a that supports the continuous girder 1 across multiple diameters connects a number of steel members 4 such as horizontal members 4a, diagonal members 4b, and steel pipe legs 4c. A pier foundation 8 supported by a steel pipe pile 6 penetrating through the leg 4c of the frame structure (jacket) 5 and placed on the water bottom ground 7, and a plurality of pier foundations 8 spaced apart from the upper end of the pier foundation 8 in the bridge axis direction. The leg body 9 is raised and configured.

  In addition, each said steel pipe pile 6 and leg 4c are integrated, and the pier foundation 8 which fixed the said frame structure 5 to the underwater ground 7 with the steel pipe pile 6 is comprised.

  The legs 9 are raised from the upper end of the pier foundation 8 at intervals in the bridge axis direction, and extend the steel pipe leg 4c constituting the frame structure (jacket) 5 upward (in the case of illustration). ) Alternatively, the lower part of the steel pipe column or prism may be fixed to the upper end of the frame structure (jacket) 5 and started up. Further, when the steel pipe pile 6 supporting the frame structure (jacket) 5 is extended as it is and the upper portion of the steel pipe pile 6 is used as the leg body 9, the structure can be simplified and the upper work load of the bridge 3 is directly applied to the steel pipe. It can be transmitted to the pile 6.

  In addition, what used the steel pipe pile 6 or the steel pipe pillar as the leg body 9 is good to increase the rigidity by filling the concrete 12 like the form of illustration. More specifically, in the illustrated form shown in FIG. 5, the concrete 12a is filled so as to be supported by the bottom mold disposed inside the leg 9, and a steel lid is fixed and closed on the top. .

  In order to reduce the negative bending moment generated, it is preferable that the interval between the plurality of legs 9 rising at intervals in the bridge axis direction is as large as possible, but if it is too wide, the jacket pier 2a is enlarged. Need to be made.

  Further, if the distance between the legs 9 in the direction of the bridge axis is too narrow, the effect of the present invention for reducing the negative bending moment generated cannot be obtained.

  For example, the distance between the legs 9 in the direction of the bridge axis is approximately 10% of the span length, although it depends on the span length of the continuous girder 1, the depth of water installed in the bridge pier 2 and the ground. For example, in the continuous girder 1 having a span length of 50 m to 200 m, the distance between the legs 9 is about 5 m to 20 m, preferably about 10 m.

  As shown in FIG. 5 to FIG. 8, the leg 9 and the bridge girder support portion 10 of the continuous girder 1 are fixed to the end of the main girder in the direction of the bridge axis with the inside of the bridge girder support portion 10 of the continuous girder 1 as the space portion 13. The bridge girder support block 14 is manufactured in which the main girder 1a and the main girder 1a for connecting the girder and the two girder 1b orthogonal to the grid are formed in a lattice shape and the space for fixing the leg 13 is provided at the intersection. The upper part of the leg 9 is inserted into the leg fixing space 13 by hanging the bridge block 14 on the leg 9 of the jacket bridge pier 2 a that is installed in advance, and hanging the bridge girder support block 14. Next, a bottom mold 15a is attached to the gap of the opening 15 around the leg 9, and the leg fixing space 13 around the upper part of the leg 9 is filled with concrete 12 and fixed.

  In order to make it as described above, as shown in FIGS. 5, 7, and 8, on the lower surface side of the bridge girder support portion 10, for inserting a leg body capable of absorbing construction errors in the bridge axis direction and the bridge axis perpendicular direction. A rectangular opening 15 is provided, and the top of the leg 9 has a clearance with respect to the height of the leg fixing space 13 so as to absorb construction errors in the vertical direction. Yes.

  In addition, each leg 9 provided at intervals in the bridge axis direction is provided with a number of legs 9 in parallel at predetermined intervals according to the width of the continuous girder 1 in the direction perpendicular to the bridge axis.

  Further, the bridge girder support portion 10 of the continuous girder 1 is formed of a steel box-shaped cross girder 1b in a direction orthogonal to the main girder ends 1a in the bridge axis direction parallel to each other at intervals in the direction perpendicular to the bridge axis. Inside, the vertical steel plate 18 is fixed to the side plate 19 of the box-shaped cross girder 1b so as to be connected to the web of the main girder end portion 1a on the extended line of the web of the main girder end portion 1a, and is spaced in the direction perpendicular to the bridge axis. The interior of the bridge girder support portion 10 of the continuous girder 1 is made into a steel shell structure by the two vertical steel plates 18 and the side plates 19a and the upper and lower face plates 19b of the box-shaped cross girder 1b. This is part 13.

  As described above, the leg fixing space (cavity) 13 has a steel shell structure, and the size of the inner leg fixing space 13 and the opening 15 can absorb the construction error and the leg 9 can be inserted. Thus, the size is determined with a margin for the expected three-dimensional construction error Δx (bridge axis direction construction error), Δy (bridge axis perpendicular direction construction error), and Δh (vertical direction construction error).

  It should be noted that it is possible to improve the integration by providing the inner wall of the fixing space portion 13 of the fixing portion and the outer periphery of the leg body 9 by providing a stopper 16 such as a stud diver. Further, when the concrete 12 is filled into the leg fixing space 13, the gap between the cavity bottom surface side opening 15 and the leg 9 is closed with a bottom mold 15a. Further, it is preferable that the inside of the leg body 9 is filled with concrete, and a steel plate lid is provided on the top of the leg body 9.

  When the bridge girder support 10 of the continuous girder 1 and the leg 9 are fixed (rigidly coupled), as shown in FIG. The continuous girder 1 is constructed by welding or bolting to the girder 1a.

  Next, the continuous girder 1 in the continuous girder bridge 3 of the present invention supported by a plurality of legs 9 (a plurality of positions) spaced in the bridge axis direction at the upper part of the jacket pier 2a is provided at one position in the bridge axis direction. The point which becomes smaller than the negative bending moment of the supported conventional continuous girder 1 will be described with reference to FIGS.

FIG. 9 shows an embodiment of the present invention in which the legs 9 on the intermediate bridge piers supporting the continuous girder 1 are arranged at a distance W in the bridge axis direction, and the continuous girder is rigidly coupled to apply an equal load (dead load) action. The bending moment figure of the made continuous girder is shown.
In the vicinity of the intermediate pier, cause negative bending moment, in between the left and right legs 9, 9 (W), the maximum negative bending moment -M ₁ becomes, in the middle of the span (L), the maximum positive bending moment + M.
FIG. 10 shows a bending moment diagram for a uniform girder of a continuous girder supported at one point by an intermediate pier in the conventional example. At the fulcrum portion of the intermediate pier, the negative maximum bending moment −M ₂ and the span (L) A positive bending moment + M is generated.

Comparing the bending moment diagrams of FIG. 9 and FIG. 10, in the support structure of the bridge pier 2 and the continuous girder 1 in the continuous girder bridge to which the present invention is applied, the span between Bridge girder of intermediate bridge pier with continuous girder 1 fixedly supported by two legs 9 with a distance W (W = 0.1L, 0.05L on one side) in the direction of the bridge axis on both sides centering on the boundary center line C The negative bending moment −M ₁ generated in the support portion 10 is about 22% smaller than the negative bending moment −M ₂ of the conventional continuous girder 1. Therefore, according to the continuous girder bridge of the present invention, the bridge girder structure of the bridge girder support portion can be made compact and economical. The magnitude of the bending moment at the center of the span is not significantly different between the present invention and the conventional example.

  As described above, the present invention is a continuous girder type bridge structure that is advantageous in terms of structural mechanics. The bridge pier 2 that supports the continuous girder 1 is excellent in quality control, can shorten the local construction period, and has horizontal strength and earthquake resistance. In the bridge girder support portion 10 of the continuous girder 1, the jacket pier 2a having excellent properties is adopted, and a plurality of leg bodies 9 raised from the upper end of the jacket-type pier foundation 8 at intervals in the bridge axis direction are used. By fixing the continuous girder 1, a continuous girder bridge can be obtained in which the magnitude of the negative bending moment generated in the continuous girder 1 of the pier 2 is reduced.

  The fixing means for the bridge pier 2a and the bridge girder support 10 of the continuous girder 1 according to the present invention is such that the upper part of the leg 9 raised from the upper end of the jacket-type bridge pier foundation 8 is provided on the bridge girder support 10 of the continuous girder. It is inserted into the fixing space 13 and filled with concrete 12 and fixed. The fixing space 13 and the opening 15 can absorb construction errors (horizontal deviation Δx, Δy, vertical deviation Δh) of the leg 9, so that the continuous girder 1 is attached to the leg 9 of the installed jacket pier 2 a. Can be easily fixed.

It is a whole side view of the 3 span continuous girder bridge supported with the jacket pier which concerns on one Embodiment of this invention. It is a side view which shows a part of pier and continuous girder support part shown in FIG. It is an AA arrow line view of FIG. It is a BB arrow sectional view (bridge axis perpendicular direction sectional view) of Drawing 3. It is sectional drawing which expands and shows a part (combined state of a leg and a bridge girder support part) of FIG. It is a partially notched perspective view which shows the fixation structure of the internal structure of a continuous girder support part, and the leg body of a bridge pier upper part. It is a perspective view which expands and shows a part (fixing space part and leg) of FIG. FIG. 5 is a plan view taken along the line CC in FIG. 4. It is a bending moment figure when a dead load acts on the 2 span continuous girder in this invention. It is a bending moment figure of the continuous girder between 2 diameters of a conventional system. It is a perspective view which shows the bridge using the jacket pier structure of a prior art example.

Explanation of symbols

1 Continuous girder 1a End main girder or cross girder main girder 1b Box-shaped girder 2 Bridge pier 2a Jacket pier 3 Continuous girder bridge 4 Steel member 4a Horizontal material 4b Diagonal material 4c Leg 5 Frame structure (jacket)
6 Steel pipe pile 7 Submerged ground 8 Pier base 9 Leg 10 Bridge girder support 12 Concrete 12a Concrete 13 Leg fixing space 14 Bridge girder support block 15 Opening 15a Bottom mold 16 Slip 17 Intermediate girder 18 Vertical steel plate 19a Side plate 19b Top plate or bottom plate 20 Jacket pier 21 Guide member 22 Jacket structure 23 Underwater foundation 24 Pile 25 Footing 26 Bridge pier 27 Continuous girder bridge 28 Floor slab

Claims (3)

A multi-girder continuous girder bridge with a continuous girder and pier rigidly connected. The pier is a bridge pier foundation in which a frame structure connecting a number of steel members is fixed to the submarine ground by a plurality of steel pipe piles. A jacket pier constructed by standing up a plurality of legs spaced apart in the axial direction, and supported by a jacket pier characterized by rigidly connecting the upper part of the legs to a bridge girder support portion of a continuous girder Continuous girder bridge.
The continuous girder bridge supported by the jacket bridge pier according to claim 1, wherein the leg body includes a steel pipe pile that fixes a frame structure extending upward from an upper end of the pier foundation and fixed to a bridge girder support portion.
  The means for fixing the upper part of the leg to the bridge girder support part is to insert the upper part of the leg into the fixing space part opened in the bottom surface provided in the bridge girder support part and to fill the fixing space part with concrete. A continuous girder bridge supported by a jacket pier according to claim 1 or 2.

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