JP2971044B2 - Truss bridge - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a truss bridge in which upper and lower chord members are made of prestressed concrete and diagonal members are made of steel.

[0002]

2. Description of the Related Art As a truss bridge, for example, a steel bridge as shown in FIG. 15 is known. In this steel bridge, the upper chord (not shown), the lower chord 1, the diagonal 2 and the like are composed of steel, and the gusset plate 1a provided on the upper chord or the lower chord 1 and the diagonal 2 are connected by rivets or the like. It is configured as follows. But,
In such a steel bridge, since each steel material must be processed with an accuracy of mm unit, construction management is troublesome,
There was a disadvantage that the material cost was high.

As a truss bridge, a concrete bridge made of prestressed concrete is also known. This concrete bridge can reduce the material cost, but the construction accuracy is inferior. The tip of the bridge girder may not be aligned at the center between the piers. Therefore, even in the case of a concrete bridge, in order to construct the bridge girder with high accuracy,
There is a disadvantage that the concrete construction management becomes very troublesome. In the case of concrete bridges,
The point structure that connects the upper chord material or the lower chord material increases,
There is a disadvantage that the weight increases.

[0004]

As described above, in the conventional truss bridge, the construction management is simplified, the weight is reduced,
It has been an issue to reduce costs and the like.

[0005] The present invention has been made in view of the above points, and an object of the present invention is to provide a truss bridge in which construction management is easy and weight and cost can be reduced.

[0006]

According to a first aspect of the present invention, an upper chord material (11) and a lower chord material (12) are made of prestressed concrete, and a diagonal material (13) is made of a steel material. The truss bridge is constructed by connecting the ends of adjacent diagonal members (13) via universal joints (14), and burying the universal joints (14) in prestressed concrete, thereby forming each diagonal member. (13) and the upper chord (11) or the lower chord (12) are connected to each other.

According to a second aspect of the present invention, in the first aspect, the universal joint (14) comprises a female member (17) provided on one adjacent diagonal member (13) and the other diagonal member. (13) provided with a male member (18), wherein the female member (17) has a conical inner surface (17b), and the male member (18) is provided with a female member (17). ) Has a spherical outer surface (18b) fitted to the conical inner surface (17b).

According to a third aspect of the present invention, in the first or second aspect, through holes (17c, 18c) are provided in the axis of the universal joint (14), and the through holes (17c, 18c) are provided.
18c) is characterized by passing a PC steel material.

According to a fourth aspect of the present invention, there is provided the universal joint (14) according to the first, second or third aspect of the invention.
Are characterized in that they are arranged on the intersections of the axes (L) passing through the centroids of the adjacent slant members (13).

According to a fifth aspect of the present invention, in the first, second, third or fourth aspect of the invention, the universal joint (14) holds the end of the sheath through which the PC steel material passes. A receiving portion (21) is provided.

[0011] In the invention according to claim 1,
The angle formed by the adjacent diagonal members (13) can be easily adjusted by the universal joint (14).
The end of 3) can be connected to the upper chord (11) or the lower chord (12). The prestress on the upper chord material (11) and the lower chord material (12) is performed after the concrete is hardened.

[0012] For example, in the case of constructing by the overhanging erection method, the bridge girder is to be extended for each block of a predetermined length.
Since the angle formed by 3) can be easily adjusted by the universal joint (14), the construction can be performed while correcting the position of the block so as to always match the target. Therefore, there is an advantage that the construction can be performed with high accuracy and the construction management of the concrete can be performed by ordinary simple construction management.

Also, a universal joint (14) and a diagonal member (13)
Is fixed in a state where it is compressed with prestressed concrete, so that the diagonal member (13) and the upper chord material (11) or the lower chord material (12) can be firmly connected. Furthermore, since the universal joint (14) is only buried in the upper chord (11) or the lower chord (12) together with the end of the diagonal (13), these diagonal (13)
The point structure connecting the upper chord material (11) or the lower chord material (12) does not become large. Moreover, diagonal materials (13)
Is made of steel, the weight can be reduced.

Further, the upper chord material (11) and the lower chord material (1)
Since 2) is made of prestressed concrete, construction management is simple, and weight can be reduced, cost can be reduced.
The reduction in weight is also advantageous in improving the earthquake resistance.

In the invention according to claim 2, since the conical inner surface (17b) of the female member (17) and the spherical outer surface (18b) of the male member (18) are fitted, The male member (18) can be securely held on the entire circumference of the conical inner surface (17b). Therefore, each diagonal material (1
3) can be stably and reliably connected, and minute angle adjustment can be easily performed.

In the invention according to claim 3, since the through-holes (17c, 18c) are provided in the axis of the universal joint (14), and the PC steel material is passed through the through-holes (17c, 18c), each diagonal member ( 13) and the upper chord (11) or the lower chord (1)
2) can be connected more firmly. Moreover,
There is also an advantage that the diagonal member (13) can be moved by a crane or installed at a predetermined position using the through holes (17c, 18c).

In the invention according to claim 4, since the universal joint (14) is located on the intersection of the axis (L) passing through the center of gravity of each adjacent diagonal member (13), the universal joint (14)
Therefore, the compressive or tensile force acting on the diagonal member (13) always passes through the center of the diagonal member (13). Therefore, an uneven load does not act on the diagonal member (13), and the strength can be improved.

In the invention according to claim 5, the PC steel material is passed through the sheath. However, since the receiving portion (21) for holding the end of the sheath is provided on the universal joint (14), the sheath is provided. Of the diagonal member (13) and the upper chord member (1)
1) or the lower chord material (12) can be further firmly and reliably connected.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on embodiments with reference to the drawings. 1 to 6 show a first embodiment, FIGS. 7 to 9 show a second embodiment, FIGS. 10 to 12 show a third embodiment, and FIGS. 13 to 14 show a fourth embodiment.

First, a first embodiment will be described with reference to FIGS. The truss bridge 10 shown in the first embodiment is shown in FIG.
As shown in FIG. 6, the upper chord 11 and the lower chord 12 are made of prestressed concrete, and the diagonal 13 is made of steel. Each end of the adjacent diagonal member 13 is connected via a universal joint 14 (see FIGS. 1 to 4), and is connected to the upper chord member 11 or the lower chord member 12 by embedding the universal joint 14 in prestressed concrete. The structure has been.

Hereinafter, a connection structure between the lower chord member 12 and the diagonal member 13 will be described with reference to FIGS.

The diagonal member 13 is formed in a tubular shape having a rectangular cross section. The lower end of the diagonal member 13 is cut diagonally.
Are fixed by welding. The lower edge of the diagonal member 13 is connected to the joint mounting plate 15 by a reinforcing plate 16 as shown in FIG.

The adjacent diagonal members 13 are arranged so that the joint mounting plates 15 face each other.
Each joint mounting plate 15 is formed with a circular positioning hole 15a at a coaxial position. And one joint mounting plate 1
A female member 17 is fixed to 5 by welding, and a male member 18 is fixed to the other joint mounting plate 15 by welding.

The female member 17 is formed in a rectangular plate shape, and has a positioning hole 15a of one joint mounting plate 15.
The positioning projection 17a fitted to the
7a, a conical inner surface 17b formed coaxially with the positioning projection 17a, and a positioning projection 17
a and through hole 1 formed coaxially in conical inner surface 17b
7c.

The male member 18 is formed in the shape of a square plate, and the positioning hole 15a of the other joint mounting plate 15 is formed.
The positioning projection 18a fitted to the
It has a spherical outer surface 18b protruding to the opposite side of 8a and formed coaxially with the positioning projection 18a, and a through hole 18c formed coaxially with the positioning projection 18a and the spherical outer surface 18b.

The conical inner surface 17b and the spherical outer surface 18
b is fitted so as to slide freely and smoothly. The female member 17 and the male member 18 are formed of cast steel, and the square outer peripheral portions are fixed to the joint mounting plates 15 by welding. Further, the one positioning hole 15a and the positioning projection 17a, and the other positioning hole 15a and the positioning projection 18a are connected by a ring-shaped filling 19 that cuts into a wedge shape.

A wedge 20 is driven into the female member 17 and the male member 18 from opposing surfaces from above and below. The wedge 20 is capable of finely adjusting the angle between adjacent diagonal members 13 depending on the amount of the wedge.

The through holes 17 of the female member 17 and the male member 18
The PC steel wire (PC steel material) not shown passes through c and 18c. A tubular sheath (not shown) through which the PC steel wire passes is arranged coaxially with each of the through holes 17c and 18c, and the end of the sheath has a positioning protrusion 17a or a positioning protrusion. 18a. That is, a concave portion is formed by the positioning hole 15a of the joint mounting plate 15 and the end surface of the positioning convex portion 17a or the positioning convex portion 18a, and the concave portion serves as the receiving portion 21 for holding the end of each sheath. I have. Further, the diagonal member 13 is formed with a hole 13a for passing the sheath.

The universal joint 14 includes a joint mounting plate 15
, A female member 17 and a male member 18. When the intersection point between the axis of the through holes 17c and 18c and the surface including the portion where the conical inner surface 17b and the spherical outer surface 18b are in contact is P, the intersection point P passes through the centroid of each diagonal member 13. It is located on the axis L. That is, the universal joint 14 is located on the intersection of the axis L passing through the centroid of each of the adjacent diagonal members 13.

At the lower end of the diagonal member 13, groove-shaped steel members 22 are fixed on both sides by welding. The adjacent diagonal members 13 are connected by connecting the respective grooved steel members 22 with the connecting plates 23 and the bolts and nuts 24.

On the other hand, the lower chord material 12 has
A sheath 25 and a PC steel wire 26 are provided. Also,
The upper chord material 11 is also provided with the same sheath and PC steel wire as the lower chord material 12. Further, the end of the diagonal member 13 embedded in the upper chord member 11 has the same structure as that shown in FIGS. 5 and FIG.
Reference numeral 60 denotes a PC steel wire projecting to the outside.

In the truss bridge 10 constructed as described above, after the conical inner surface 17b and the spherical outer surface 18b of the universal joint 14 are fitted, the adjacent diagonal members 13 are connected to the grooved steel members 22 and the connecting plate. 23 and bolt nut 24. At this time, while adjusting the angle between the adjacent diagonal members 13 according to the amount of the wedge 20
Tighten 4. Thus, the angle between the adjacent diagonal members 13 can be easily adjusted. Then, after adjusting the angle, concrete is struck and the end of the diagonal member 13 is connected to the upper chord member 11 or the lower chord member 12. The prestress on the upper chord member 11 and the lower chord member 12 is performed by applying tension to the PC steel wire passing through the through holes 17c and 18c and the other PC steel wire 26 after the concrete is hardened.

For example, in the case of the construction by the overhanging erection method, the bridge girder is constructed so as to overhang the bridge girder for each block of a predetermined length. Therefore, the construction can be performed while correcting the position of the block so as to always match the target. Therefore, the construction can be performed with high accuracy, and the construction of the concrete can be managed by ordinary simple construction management.

Further, since the ends of the universal joint 14 and the diagonal member 13 are fixed in a state of being compressed by prestressed concrete, the diagonal member 13 and the upper chord member 11 or the lower chord member 12 are firmly connected. be able to. Further, since the universal joint 14 is only buried in the upper chord material 11 or the lower chord material 12 together with the end of the diagonal material 13, the diagonal material 13 is connected to the upper chord material 11 or the lower chord material 12. The case structure does not become large. Moreover, since the diagonal members 13 are made of steel, the weight can be reduced.

Further, the through holes 17c, 1
Since the PC steel wire is passed through 8c, each diagonal member 13 and the upper chord member 11 or the lower chord member 12 can be more firmly connected. Further, by using the through holes 17c and 18c, there is an advantage that the diagonal member 13 can be moved by a crane or installed at a predetermined position.

Further, the end of the sheath is connected to the universal joint 14.
, The position of the sheath can be stabilized, and the diagonal member 13 and the upper chord member 11 or the lower chord member 12 can be more firmly and reliably connected by the sheath. be able to.

Since the upper chord material 11 and the lower chord material 12 are made of prestressed concrete, the construction management is simple, and the weight can be reduced, the cost can be reduced. The reduction in weight is also advantageous in improving the earthquake resistance.

Further, the universal joint 14 has an advantage that the spherical outer surface 18b can be held securely and smoothly over the entire circumference of the conical inner surface 17b. Thus, the respective diagonal members 13 can be stably and reliably connected, and fine angle adjustment can be performed smoothly and easily.

Furthermore, each of the diagonal members 1 adjacent to the universal joint 14
3 is located on the intersection of the axis L passing through the centroid of FIG. 3, the compressive or tensile force acting on the diagonal member 13 from the universal joint 14 always passes through the centroid of the diagonal member 13. Therefore, an unbalanced load does not act on the diagonal member 13, and the strength can be improved.

Next, a second embodiment of the present invention will be described with reference to FIGS.
This will be described with reference to FIG. However, the same elements as those of the first embodiment are denoted by the same reference numerals, and description thereof will be simplified. The difference between the second embodiment and the first embodiment is that
The point is that adjacent diagonal members 13 are directly connected by bolts and nuts 27.

That is, the adjacent diagonal members 13 are
7 and the bolt nut 27 provided at a position penetrating the four corners of the male member 18 and the joint mounting plate 15 corresponding to the four corners.
Is connected by. Both ends of the diagonal member 13 are constituted by joint ends 131, and the joint ends 131 are welded to both ends of a square pipe 130 constituting a main part of the diagonal member 13.

The joint end 131 is formed of a portion excluding the female member 17 or the male member 18, and includes a partition plate 131 a for welding connection to the square pipe 130 and a joint mounting plate 15.
And the reinforcing plate 131b.
In this embodiment, the joint end 131 is integrally formed by welding. Note that the joint end 131 may be integrally formed of cast steel. Further, the joint mounting plate 15 and the female member 17 or the male member 18 may be integrally formed of cast steel. Further, the entire joint end 131 and the female member 17 or the male member 18 may be integrally formed of cast steel.

In the truss bridge 10 configured as described above, the same operation and effect as in the first embodiment can be obtained. Moreover, if the deformation is restrained by welding to a reinforcing bar disposed inside the concrete, the grooved steel member 22 and the connecting plate 23 can be omitted, so that the number of parts and the cost can be reduced.

Next, a third embodiment of the present invention will be described with reference to FIGS.
This will be described with reference to FIG. However, the same elements as those of the first embodiment are denoted by the same reference numerals, and description thereof will be simplified. The third embodiment differs from the first embodiment in that both ends of the diagonal member 13 are formed thin.

That is, both ends of the diagonal member 13 are constituted by joint ends 132, and the joint ends 132
Are welded to both ends of a square pipe 130 constituting a main part of the diagonal member 13. Then, the joint end 132 approaches each other so as to be curved in a circular arc shape from a pair of wall surfaces facing each other of the square pipe 130, and the two curved plates 1 contacting each other.
32a and 132b. Curved plate 13
2a, 132b, in the contact and overlapping part,
The female member 17 or the male member 18 is fixed by welding.

For this reason, the joint end 132 is connected to the female member 17.
Alternatively, the second moment of area of the portion close to the male member 18 is the smallest, and it is easy to be deformed by the bending moment in the direction in which the angle of the adjacent diagonal member 13 is changed. The second moment of area of at least the portion projecting from the female member 17 or the male member 18 is smaller than the other portions of the diagonal member 13. However, the sectional area of the joint end 132 is equal to or greater than the sectional area of the square pipe 130. That is, the joint end 132 is designed so that the tensile
It is configured to have strength equal to or higher than.

In the truss bridge 10 constructed as described above, after the concrete as the upper chord material 11 or the lower chord material 12 is cast and hardened, when prestress is applied, the upper chord material 11 or the lower chord material is 12 is slightly deformed by compression. Therefore, a bending moment in a direction that changes the angle of the adjacent diagonal members 13 may slightly act on each diagonal member 13 due to the compressive deformation. However, since the second moment of area of the joint end 132 is smaller than the bending moment, the joint end 1
The portion protruding from the upper chord material 11 or the lower chord material 32 is slightly bent in the bending direction, so that the compressive deformation due to the prestress can be absorbed.

Therefore, the strength of the diagonal member 13, the upper chord member 11, the lower chord member 12, and the like can be improved. In addition, since the joint end 132 has a small section modulus, the bending stress generated at the joint end 132 is extremely small, and the joint end 132 does not have any problem in strength. Further, in the direction orthogonal to the direction in which the angle of the adjacent diagonal member 13 is changed, the lowering of the second moment of area at the end of the diagonal member 13 is reduced.
That is, there is an advantage that the rigidity of the end of the diagonal member 13 is high in a direction different from the direction in which the angle of the adjacent diagonal member 13 is changed.

Next, a fourth embodiment of the present invention will be described with reference to FIGS.
This will be described with reference to FIG. However, components common to those of the third embodiment are denoted by the same reference numerals, and description thereof will be simplified. The fourth embodiment differs from the third embodiment in that an intermediate plate 13 is further provided between the curved plates 132a and 132b.
2c is provided.

That is, the joint end 132 is
2c is formed longer than the curved plates 132a and 132b, and the intermediate plate 132c extends to the back side of the female member 17 or the male member 18. And one curved plate 132a
The intermediate plate 132c is connected to the female member 17 or the male member 18 by welding. The intermediate plate 132c is connected to the inner surface of the square pipe 130 by welding in the square pipe 130. Further, the curved plates 132a and 132b and the intermediate plate 1
32c is connected by welding at a portion overlapping in parallel. Although the grooved steel material 22 and the connecting plate 23 are not shown, they are provided similarly to the third embodiment.

The truss bridge 10 configured as described above has the same operation and effect as the third embodiment. However, since the intermediate plate 132c is provided, the female member 1
The strength of the joint end 132 in the vicinity of the male member 7 or the male member 18 can be improved.

[0052]

According to the first aspect of the present invention, the angle formed by the adjacent diagonal members (13) can be easily adjusted by the universal joint (14). By hitting, the end of the diagonal member (13) can be connected to the upper chord member (11) or the lower chord member (12). The upper chord material (11) and the lower chord material (1
The pre-stress for 2) is performed after the concrete is hardened.

For example, in the case of the construction by the overhanging erection method, the bridge girder is to be extended for each block of a predetermined length.
Since the angle formed by 3) can be easily adjusted by the universal joint (14), the construction can be performed while correcting the position of the block so as to always match the target. Therefore, there is an advantage that the construction can be performed with high accuracy and the construction management of the concrete can be performed by ordinary simple construction management.

The universal joint (14) and the diagonal member (13)
Is fixed in a state where it is compressed with prestressed concrete, so that the diagonal member (13) and the upper chord material (11) or the lower chord material (12) can be firmly connected. Furthermore, since the universal joint (14) is only buried in the upper chord (11) or the lower chord (12) together with the end of the diagonal (13), these diagonal (13)
The point structure connecting the upper chord material (11) or the lower chord material (12) does not become large. Moreover, diagonal materials (13)
Is made of steel, the weight can be reduced.

Further, the upper chord material (11) and the lower chord material (1)
Since 2) is made of prestressed concrete, construction management is simple, and weight can be reduced, cost can be reduced.
The reduction in weight is also advantageous in improving the earthquake resistance.

In the invention according to claim 2, since the conical inner surface (17b) of the female member (17) and the spherical outer surface (18b) of the male member (18) are fitted, The male member (18) can be securely held on the entire circumference of the conical inner surface (17b). Therefore, each diagonal material (1
3) can be stably and reliably connected, and minute angle adjustment can be easily performed.

According to the third aspect of the present invention, the through-holes (17c, 18c) are provided in the axis of the universal joint (14), and the PC steel material is passed through the through-holes (17c, 18c). 13) and the upper chord (11) or the lower chord (1)
2) can be connected more firmly. Moreover,
There is also an advantage that the diagonal member (13) can be moved by a crane or installed at a predetermined position using the through holes (17c, 18c).

In the invention according to claim 4, since the universal joint (14) is located on the intersection of the axis (L) passing through the centroid of each of the adjacent diagonal members (13), the universal joint (14)
Therefore, the compressive or tensile force acting on the diagonal member (13) always passes through the center of the diagonal member (13). Therefore, an uneven load does not act on the diagonal member (13), and the strength can be improved.

According to the fifth aspect of the present invention, the PC steel material is passed through the sheath. However, since the receiving portion (21) for holding the end of the sheath is provided in the universal joint (14), the sheath is provided. Of the diagonal member (13) and the upper chord member (1)
1) or the lower chord material (12) can be further firmly and reliably connected.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a truss bridge shown as a first embodiment of the present invention.

FIG. 2 is a view showing a main part of the truss bridge, and is II in FIG.
-Arrow view along the II line.

FIG. 3 is an exploded perspective view of a main part of the truss bridge.

FIG. 4 is a perspective view of a main part of the truss bridge.

FIG. 5 is a perspective view of the truss bridge.

FIG. 6 is a perspective view of the truss bridge.

FIG. 7 is an exploded perspective view of a main part of a truss bridge shown as a second embodiment of the present invention.

FIG. 8 is a fragmentary perspective view of the truss bridge.

FIG. 9 is a perspective view of a main part of the truss bridge.

FIG. 10 is a sectional view of a main part of a truss bridge shown as a third embodiment of the present invention.

FIG. 11 is an exploded perspective view of a main part of the truss bridge.

FIG. 12 is a perspective view of a main part of the truss bridge.

FIG. 13 is an exploded perspective view of a main part of a truss bridge shown as a fourth embodiment of the present invention.

FIG. 14 is a fragmentary perspective view of the truss bridge.

FIG. 15 is a perspective view of a main part of a truss bridge shown as a conventional example.

[Explanation of symbols]

 Reference Signs List 10 truss bridge 11 upper chord material 12 lower chord material 13 diagonal material 14 universal joint 17 female member 17b conical inner surface 17c through hole 18 male member 18b spherical outer surface 18c through hole 21 receiving portion L axis

Claims (5)

(57) [Claims] 1. A truss bridge in which an upper chord member (11) and a lower chord member (12) are made of prestressed concrete and a diagonal member (13) is composed of steel material, wherein each end of an adjacent diagonal member (13) is provided. Are connected via a universal joint (14), and the universal joint (14) is buried in prestressed concrete, thereby connecting each diagonal member (13) with the upper chord material (11) or the lower chord material (12). A truss bridge characterized by being configured as follows. 2. The universal joint (14) comprises a female member (17) provided on one adjacent diagonal member (13) and a male member (18) provided on the other diagonal member (13). The female member (17) has a conical inner surface (17b),
The truss bridge according to claim 1, wherein the male member (18) has a spherical outer surface (18b) that fits into the conical inner surface (17b) of the female member (17). 3. A through hole (17) is formed in the axis of the universal joint (14).
The truss bridge according to claim 1 or 2, wherein a PC steel material is passed through the through holes (17c, 18c). 4. The universal joint (14) is arranged at the intersection of an axis (L) passing through the center of gravity of each adjacent diagonal member (13). Claim 3
The truss bridge described. 5. The universal joint (14) is provided with a receiving portion (21) for holding an end of a sheath through which a PC steel material passes. Or the truss bridge according to claim 4.