JP2720789B2 - Cable stiffening water pipe 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 cable stiffening water pipe bridge for supporting the weight of a water pipe bridge main body and the water weight in a pipe by the rigidity of the water pipe bridge main body itself and the stiffening of the cable.

[0002]

2. Description of the Related Art A water pipe bridge has a simple pipe beam method in which a water pipe itself is simply supported as a beam at both ends. However, in places where this method is difficult to apply, for example, in valleys where piers are difficult to be installed or in terrain on soft ground, Also, if the rigidity of the water pipe itself is insufficient due to the long span due to the regulation of river land,
Stiffened water pipe bridge is applied. The stiffening method is further classified into various types, and the cross section is T, Y,
There are stiffened flange type in which π-shaped steel is directly welded, truss stiffened type in which the water pipe is the upper or lower chord, and Langer type in which the water pipe is used as the stiffening girder of the Langer Bridge. And many others have been adopted.

Each of these models has its own characteristics.
It goes without saying that the most suitable method should be selected for the topography of the erection, but generally speaking, the truss stiffening type requires a large amount of high-strength steel to construct the truss. Similarly, the use of high-strength steel materials in constructing the bridge will increase the weight of the bridge as a whole, so all of the foundation costs, material costs, and construction costs will have to rise, and the economic burden will be light. It is hard to say. In addition, the suspension bridge model and the cable stay stiffening model require erecting a long tower, so that both material costs and construction costs are inevitably rising.

Conventional techniques aiming at solving such a problem have been found, and as an example, FIG.
In the Japanese Patent Publication No. 217504, both ends 11 of the water pipe bridge main body 1a are described.
a is supported by the abutment 2a, and a plurality of support members 3a whose heights are sequentially reduced from the center of the water pipe bridge main body 1a toward both ends 11a are suspended, and cable support portions are respectively provided at lower ends of these support members 3a. Are provided, and a cable 5a is hung over these cable support portions, and both ends thereof are fixed to the abutment 2a. This configuration realizes a much lighter weight than conventional truss type and arch type, and requires less pressure receiving area on the side than rigid arch and truss, so wind load can be reduced, and in this respect also lightweight It is said that the promotion can be promoted.

[0005]

The prior art cited in FIG. 5 is a structure in which a suspension bridge type stiffener is turned upside down, and a long tower erected at both ends of the bridge by reversing is omitted. The points that can be done can be evaluated. However, in order to form a cable curve instead of a tower, a large number of supports 3a must be hung from the water pipe bridge main body 1a, and the smaller the number of the supports, the less the vertical load is carried. Since it is disadvantageous in terms of strength when concentrated at points, a large number of support members that only draw an arc are required if they are connected. It remains questionable whether significant savings in material and work can be achieved. In addition, according to the embodiment shown in the figure, the shaft 101 is provided at both ends of the water pipe bridge main body 1a, the cable is wound, and the anchor is taken and locked in the abutment.
Isn't there a need for complicated work, and there is still a problem with adjusting the tension of the cable?

[0006] This type of stiffening is intended mainly for vertical loads, and has a small pressure receiving area on the side surface, so that it is more advantageous for a lateral wind load than a rigid stiffening type. Although it is said that there is, it is not a configuration that actively improved the strength in the horizontal direction. Therefore, it cannot be said that it is perfect for horizontal loads such as wind and earthquake, and this is one of the factors that limit the span length of the water pipe bridge main body.

In general, the stiffening type, which is reduced in weight and simplified with respect to the stiffening by the heavy rigid body, has low strength in the strength in the horizontal direction, which is a great limitation in selecting the type. For example, FIG. 6 shows an example of a tie rod stiffening type water pipe bridge.
b, two support members 3b with a distance s are vertically installed, and both ends 11b of the water pipe bridge main body 1b and the lower end of the support material 3b are connected and integrated by a tie rod 102, and the bending generated in the water pipe bridge main body 1b. This is a simple model that replaces stress with axial force. However, it can be said that it is not wrong to interpret that the rigidity against horizontal load is small, and in this respect it is hardly enhanced.

In order to solve the above-mentioned problems, the present invention is extremely simple in structure, is much lighter than stiffening by a rigid structure, and has two-dimensional horizontal and vertical structures. It is an object of the present invention to provide an advantageous cable stiffening water pipe bridge that has the advantage that the strength in any of the directions is significantly improved and that the span length can be set larger than before.

[0009]

A cable stiffening water pipe bridge according to the present invention supports both ends 11 of a water pipe bridge main body 1 on an abutment 2 and a Δ-shaped support substantially at the center of the water pipe bridge main body 1. A cable 5 for hanging the material 3 vertically and diagonally connecting both sides of the both ends 11 via two vertices 31 below the Δ-shaped support material 3.
The above-mentioned problem has been solved by extending the lower side of the water pipe bridge main body 1 on both sides.

More specifically, the mounting of both ends 11 of the water pipe bridge main body 1 is performed by supporting the ring girder 41 pivotally supported on the abutment 2 and the telescopic pipe 42 and the fixing gusset 44 connecting the main pipe P on the ground. The ring girder 41 is stiffened by the cable 5 passing through the vertex 31 of the Δ-shaped support member 3.

In a preferred embodiment, the supporting portion 4 has a fixed box-shaped fixing gusset 44 fixed at an angle to the ring girder 41 at a predetermined angle, and both ends of the cable 5 are connected to the head of the fixing gusset 44. A socket 45 comprising a fastening bolt 46 penetrating through the portion and projecting into the box;
And the like.

As another embodiment, in addition to the above-described stiffening with the cable, a mode in which a stiffening beam 12 of a steel, for example, a π-shaped steel material is welded to the top of the water pipe bridge main body 1 over the entire length thereof is further enhanced. Is preferred when necessary.

[0013]

FIGS. 2A and 2B are tables for explaining the stiffening action in the vertical direction of the present invention. FIG. 7A shows the conventional tie rod stiffening bridge shown in FIG. 6 in which the total length of the water pipe bridge main body 1b is S and the distance between two spaced support members 3b is s. ing. Figure (B) is a chart in which the relationship between the stiffening action of the tie rod model and the position of the support material is plotted. The vertical axis is the bridge body axial force (tension of the stiffening cable) and displacement, and the horizontal axis is s / S. Is graduated. As is clear from the axial force curve and the displacement amount curve in the figure, as s / S decreases, the axial force increases and the displacement decreases. To see the case where the water pipe bridge body is stiffened by the tension via only one support member at the center as in the present invention, look at the rightmost end of FIG. Since it is good, it can be seen that the tension approaches the maximum value that converges substantially constant, and the displacement amount approaches the minimum value that converges almost constant. Since the water pipe bridge is regulated by the amount of displacement, it is correct to judge that a small amount of displacement is an efficient configuration. That is, it is proved that the tie rod type has a stiffening action which is superior to the vertical stiffening action of the conventional tie rod type.

On the other hand, the stiffening action in the horizontal direction can hardly be expected in the prior art other than the stiffening of the rigid structure combining the cross beams as described above.
According to the present invention, the cable is not only stiffened in the vertical direction by simply applying oblique tension to the water pipe bridge main body and the vertical direction to the pipe axis, but also inclined obliquely to the horizontal direction of the pipe axis. Since a tension is applied, the horizontal component exerts a horizontal stiffening action. As a result, the water pipe bridge according to the present invention can be stiffened two-dimensionally, and it is possible to recognize a feature that enhances resistance to loads from all directions.

[0015]

FIG. 1 is a diagram showing an embodiment of the present invention. However, FIG. (A) is a plan view, FIG. (B) is a side view, and FIG. (C) is a cross-sectional view. Both ends 11 of the water pipe bridge main body 1 are respectively mounted on the abutment 2, and the support part 4 includes a ring girder 41 pivotally supported on the abutment, a telescopic pipe 42 connected to the main pipe P on the ground, and a fixing gusset. 44, the water pipe bridge main body 1 is flexibly connected to the main pipe P by a telescopic pipe 42 .

A Δ-shaped support member 3 is fixed substantially at the center of the water pipe bridge main body 1. The Δ-shaped support member 3 is formed of a welded structure made of steel and having the required strength, and is welded to the outer peripheral surface of the water pipe bridge main body 1. The height and the distance between the vertices 31 at the bottom are
In each case, a cable 5 connecting the top and the end of the water pipe bridge body 1
Are set to form a desired vertical angle θ and a horizontal angle φ. By the way, Lθ and LΦ are 10-2.
Select from the range of 0 °.

In the embodiment of the present invention, the fixing of the cable 5 is not based on the conventional anchoring method, but the work of adjusting the tension at the time of erection is easy, and the socket method which can be adjusted even during use is adopted. Maintenance benefits. FIG. 3 is a side view showing an example of the embodiment, in which a fixing gusset 44 is inserted into a mounting hole formed in a side portion of the ring girder 41.
Then, a fastening bolt 46 forming the other end of the socket 45 to which the cable 5 is attached is inserted into the box of the fixing gusset. The fastening bolt 46 is screwed with the fastening nut 47 in the box to apply tension to the cable 5, and adjusts the tension by advancing and retreating the screw. Further, a non-rotating nut 49 is fitted outside the fastening nut for maintenance.

FIGS. 4 (A) and 4 (B) show another embodiment different from FIG. 1, in which a π-shaped steel material is welded to the upper part of the water pipe bridge main body 1 as a stiffening beam 12 over its entire length. Cable 5 and Δ
In addition to the stiffening by the shaped support member 3, the structure has a structure in which resistance to bending moment is further strengthened by a rigid body. As described above, in addition to the basic cable stiffening, the application of the present invention can also use a flange type stiffening that welds any type steel such as π-type, T-type, and Y-type over its entire length, The range of choices for the required strength is wide open.

[0019]

As described above, the present invention is a simple structure and an economically advantageous construction method, but has a highly efficient stiffening in the vertical direction far exceeding the simple construction method of the prior art, and an almost powerless method. The stiffening in the horizontal direction, which is close to, can withstand loads from all directions, so it is acceptable to extend the maximum length of the span of the water pipe bridge main body, simplifying the construction work and improving workability. An effect that greatly contributes to improvement can be obtained. Naturally, construction costs can be reduced, so it is worthy of evaluation that it provided useful technology from a social perspective.

[Brief description of the drawings]

FIG. 1 is a plan view (A), a side view (B),
It is sectional drawing (C).

FIG. 2 is a stiffening diagram (A) of a tie rod type for explaining the operation of the present invention, and a relationship diagram (B) of an axial force, a displacement amount and a position of a support member.

FIG. 3 is an enlarged side view of the vicinity of a mounting portion according to the embodiment of the present invention.

FIG. 4 is a side view (A) and a sectional view (B) showing another embodiment of the present invention.

FIG. 5 is a side view showing a conventional technique.

FIG. 6 is a side view showing another conventional technique.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Water pipe bridge main body 2 Abutment 3 Delta support material 4 Support part 5 Cable 11 End part 12 Stiffening beam 31 Vertex 41 Ring girder 42 Telescopic tube 44 Fixing gusset 45 Socket 46 Fastening bolt 47 Fastening nut 48 Cover 49 Locking nut P Pipe θ Vertical angle between water pipe bridge main body and cable axis φ Horizontal horizontal angle between water pipe bridge main body and cable axis

Claims (4)

(57) [Claims] 1. A water pipe bridge main body 1 having both ends 11 supported on an abutment 2, and a Δ-shaped support member 3 suspended from substantially the center of the water pipe bridge main body 1, below the Δ-shaped support member 3. 2 vertices 31
A cable stiffening water pipe bridge characterized in that cables 5, which are diagonally connected to the support portions 4 of the both end portions 11, are respectively stretched downward on both sides of the water pipe bridge main body 1 via both ends. 2. The water pipe bridge main body 1 according to claim 1, wherein both ends 11 of the water pipe bridge main body 1 are attached to a ring girder 41 pivotally supported on the abutment 2, a telescopic pipe 42 and a fixing gusset 44 for connecting a main pipe P on the ground. And the ring girder 41 is further stiffened by the cable 5 passing through the apex 31 of the Δ-shaped support member 3. 3. The support according to claim 1, wherein the support at both ends is provided.
Each of the holding portions 4 has a box-shaped fixing gusset 44 that is fixed at an angle to the ring girder 41 at a predetermined angle,
A socket 4 comprising fastening bolts 46 at both ends of the cable 5 penetrating through the head of the fixing gusset 44 and protruding into the box.
5. A water stiffened water pipe bridge comprising an adjustment function comprising a fastening nut 47 screwed with the fastening bolt 46. 4. The stiffening beam 1 according to claim 1, wherein the stiffening beam 1 is formed on the top of the water pipe bridge main body 1 over the entire length thereof.
Cable stiffening water pipe bridge characterized by welding No. 2.