JP2000352015A - Bridge lower part permanent passage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of part items, thickness and weight of floor plates, and facilitate the work execution at work site. SOLUTION: A passage 20 is formed of a floor unit 21, column materials 29, intermediate rails 30, and handrails 31. The floor unit 21 is formed of a pair of right and left main beams 22, a plurality of auxiliary beams 23 connecting the right and left main beams 22 to each other in lattice shape, floor plates 24 installed on these beams, and installed on support members 28. The main beams 22 and the auxiliary beams 23 are formed of aluminum alloy hollow extruded material, and the floor plates 24 are formed, similarly, of the aluminum alloy extruded material into a plate-shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a permanent lower passage made of an aluminum alloy.

[0002]

2. Description of the Related Art Bridges, highways, and monorail tracks (hereinafter, collectively referred to as bridges) that are built over rivers are provided with permanent inspection passages and evacuation passages for inspecting damaged parts and repairing them at an early stage. (These are collectively referred to as permanent passages or passages). In this type of conventional passage, the main components were made of steel,
Recently, there has been a demand for improvements in weight reduction, durability, transportability, workability, etc., and various types of permanent passages made of aluminum alloy extruded materials for main components such as floorboards and pillars have been proposed. (For example, JP-A-1-125404, JP-A-4-49604, and JP-A-7-1389).
No. 16, etc.).

In the case of a permanent passage made of steel, the span of the supporting member for supporting the floorboard is set to 6 m to support only both ends of the floorboard, and the applied load (equally distributed load) applied to the floorboard is 350 mm.
When Kg / m2, the maximum amount of deflection of the passage is 1 of the span.
/ 300 (= 20 mm) or less.

On the other hand, in the case of a permanent passage made of an aluminum alloy, since the strength is not sufficient as compared with steel, the length of the floor plate is usually set to 4 m, and the end and the intermediate portion of the floor plate are supported by a support member. The maximum amount of bending of the passage is designed to be substantially equal to the amount of bending of the permanent passage made of steel.

FIG. 12 shows a conventional aluminum alloy bridge lower permanent passage. In this bridge lower permanent passage, a plurality of support members 1 are provided at regular intervals on a main girder of the bridge or a horizontal girder (not shown) bridged between the main girder, and an aluminum alloy An end portion and an intermediate portion are fixed by bridging a floor plate 2 made of an extruded material, and pillar members 3 made of an extruded material made of an aluminum alloy are erected on both outer surfaces of the floor plate 2 via mounting brackets 4. Are constructed by connecting pillars 3 and 3 adjacent to each other in the longitudinal direction with a middle rail 5 made of an extruded material made of an aluminum alloy and a handrail 6. The floorboard 2 forms a strength member by forming a rigid frame structure in which the cross-sectional shape (the cross-sectional shape orthogonal to the longitudinal direction of the passage) includes a diagonal material.

[0006]

However, in the above-described conventional aluminum alloy permanent passage, the floor plate 2 itself is heavy because the floor plate 2 itself constitutes a strength member having a rigid frame structure. Because the number of parts such as the mounting bracket 4 increases, not only takes much time for construction,
There was a problem that the weight of the passage itself also increased, and the load on the bridge was large.

Therefore, if the span of the support member 1 and the length of the floor plate 2 are set to 6 m, which is the same as the length of the permanent passage made of steel, in order to reduce the number of parts of the support member 1 and the floor plate 2, the strength in the vertical direction is increased. In addition, the thickness and the cross-sectional area of the support member 1 and the floor plate 2 must be increased, so that the weight increases,
It is necessary to manufacture the floorboard with a large extruder, which raises a new problem that the manufacturing cost increases.

Further, since the handrail 6 is attached to the inner surface of the pillar 3 so as to intersect it, when used as a handrail, a hand tip gets caught on the upper end of the pillar 3.

In the conventional passage disclosed in the above-mentioned Japanese Patent Application Laid-Open No. Hei 7-138916, the three members of the floor plate, the supporting member (supporting member) and the column member are jointly fastened by bolts. In order to assemble at a factory and transport it to a construction site, it has to be transported with the pillars attached, so that the transportation efficiency is poor, and eventually it was necessary to assemble at the construction site.

[0010] Further, aluminum is used to prevent corrosion.
Although an alumite film is formed on the surface by alumite treatment, when the components are fastened with stainless steel bolts, the alumite treatment cannot be performed even in the screw holes of the components, and even if anodized However, since the alumite film is broken by the screwing of the bolt, the dissimilar metals come into contact with each other, and aluminum is a metal having a higher ionization tendency than stainless steel.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems. An object of the present invention is to increase the strength of the entire floor unit by forming the floor unit with a floor plate and a beam. It is an object of the present invention to provide a permanent passage under a bridge that enables a reduction in the number of parts, a reduction in the thickness and weight of a floor plate, and a reduction in the weight of the passage itself, and also facilitates construction at a construction site.

[0012]

According to a first aspect of the present invention, a pair of left and right main beams made of an aluminum alloy hollow extruded member disposed in parallel on a support member along a bridge. And a plurality of sub-beams made of an aluminum alloy hollow extruded material for connecting the main beam in a ladder shape, and a floor plate made of an extruded aluminum alloy material laid on these sub-beams. It is characterized by the following.

According to a second aspect of the present invention, in the first aspect,
A plurality of pillars are attached to the outer surface of the main beam, and these pillars are connected to each other by a middle crosspiece.

According to a third aspect, in the second aspect,
A handrail is attached to the upper surface of the pillar.

In the present invention, since the main beam is made of a hollow extruded material, the main beam has high strength and supports the widthwise end of the floorboard.
In addition, a sufficient strength in the vertical direction can be obtained only by increasing the sectional height without increasing the thickness of the main beam. Since the secondary beam is made of a hollow extruded material, it has high strength and sufficient strength against the load in the width direction of the passage, and supports the intermediate portion or the intermediate portion and the end portion of the floorboard in the longitudinal direction, thereby forming the main beam. Together, they constitute the strength member of the floorboard. Therefore, a large strength is not required for the floor plate itself, and the floor plate can be formed to have the same length as the steel floor plate, and can be formed to be thin. The main beam, the sub beam, and the floor plate are integrally connected by a fastening means such as a bolt to form a floor unit, and can be assembled in a factory. The middle rail and handrail connect and reinforce the pillars. In addition, the safety of the permanent passage is improved. further,
Since the handrail is attached to the upper surface of the pillar, the finger does not hit the pillar even if the hand is moved along the handrail.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings. FIG. 1 is an external perspective view showing one embodiment of a permanent bridge lower passage according to the present invention, FIG.
Is a sectional view taken along the line II-II in FIG. 1, FIG. 3 is an enlarged sectional view taken along the line III-III in FIG. 1, FIG. 4 is a side view of a main part of the passage, and FIG. 6 is a sectional view of the main beam, FIG. 7 is a sectional view of the sub beam, FIG. 8 is a sectional view of the flange material, FIGS. 9A and 9B are front views of the floor material, FIG. 10 is a cross-sectional view of a pillar, and FIG. 11 is a front view of a handrail.

First, a schematic structure of a permanent passage 20 (hereinafter referred to as a passage) under a bridge will be described with reference to FIGS. 1 to 5. The passage 20 includes a floor unit 21. The floor unit 21 includes a pair of left and right main beams 22 arranged in parallel to each other in the width direction of the passage 20, a plurality of sub beams 23 connecting the main beams 22 in a ladder shape, A floor plate 24 spanned over the upper surfaces of the main beam 22 and the sub beam 23, an angle 25 fixed to the outer surfaces of both ends in the longitudinal direction of the main beam 22,
A plurality of bolts 34 are provided on a support member 28 which is formed of a flange member 26 or the like for fixing the sub beam 23 to the main beam 22, and the end of the main beam 22 and the angle 25 project from the side surface of a main girder 27 of a bridge (not shown). , 45. Passage 2
Numeral 0 includes a plurality of pillars 29 erected on both outer side surfaces of the floor unit 21 at predetermined intervals, and a middle rail 30 and a handrail 31 for connecting these pillars 29. The floor unit 21 has a length of 6 m, a width of 560 mm, and a height of 18
0 mm, and the height of the pillar 29 is 1100 mm.

The main beam 2 which is a component of the passage 20
2, sub beam 23, floor plate 24, angle 25, flange material 2
6. The pillar 29, the middle rail 30 and the handrail 31 are all manufactured by extrusion molding of an aluminum alloy (eg, JIS A6063S), and are subjected to an artificial age hardening treatment (T5) to increase the strength. An alumite film is formed on the surface to prevent corrosion.
Further, among these constituent members, the main beam 22, the sub beam 23, the flange member 26, the column member 29, the middle rail 30 and the handrail 31 are manufactured in a hollow shape in order to further increase the strength.

The supporting member 28 is made of H-shaped steel material, and is provided at intervals of 6 m (span) in the longitudinal direction of the bridge in the same manner as a conventional steel-made permanent passage. I support it.

Next, the structure of each component constituting the passage 20 will be described in detail. 3 and 6, the main beam 2
The upper plate 22a and the lower plate 22b are formed by a hollow extruded material having a vertically long rectangular cross-sectional shape.
And a pair of left and right side plates 22c, 22d, and both side plates 22c,
Buckling prevention rib 2 for connecting the 22d height middle part
2e are integrally provided, arranged symmetrically so as to be parallel to both sides in the width direction of the floor plate 24 and a shallow groove 33 described later is located at the center of the passage, and connected in a ladder shape by a plurality of sub beams 23. Further, since the main beam 22 is formed in a hollow shape, the strength is high, and constitutes a strength member that supports both end portions in the width direction of the floor panel 24. In this case, if the section height is increased without increasing the thickness of the main beam 22, the second moment of area increases, so that sufficient strength can be obtained in the vertical direction.

The shallow groove 33 is formed on the upper surface of the upper plate 22a at the edge on the center side of the passage over the entire length of the upper plate 22a in the longitudinal direction. The depth of the shallow groove 33 is set substantially equal to the thickness of the floor plate 24. A bolt mounting groove 35 to which the bolt 34 for fixing the main beam 22 to the support member 28 is mounted is formed in the center of the lower plate 22b in the width direction.
2b is formed over the entire length so as to open to both ends in the longitudinal direction. The lower plate 22b is connected to the bolt 3
4 and a nut 43 fixed to the upper surface of the support member 28.

The outer side plate 22c has the angle 25
Further, two bolt mounting grooves 38 and 39 to which bolts 36 and 37 for fixing the column member 29 are mounted are formed over the entire length. On the inner side plate 22d, two bolt mounting grooves 41 to which bolts 40 for fixing the flange member 26 are mounted and a bolt mounting groove 42 used when the angle 25 is mounted inside are formed. And a positioning piece 43 for supporting the longitudinal edge of the lower surface of the sub beam 23 and performing positioning in the height direction.
Are protruded integrally over the entire length. In addition, such a main beam 22 is easily formed by extrusion molding. The upper plate 22a and the lower plate 22b are connected to the side plates 22c, 2c.
The plate is formed to be slightly thicker than the 2d and the rib 22e.

Each of the bolts 34, 36, 37, and 40 (similarly for bolts to be described later) is made of stainless steel, has a dacro treatment on its surface, and its head has the bolt mounting grooves 35, 38, 39, The heads of the 41 main beams 22 are slidably inserted through openings opening to the longitudinal edges thereof. Bolt mounting grooves 35, 38, 39, 41, 42
Consists of rectangular grooves, and the bolts 34, 36, 37, 4
0 to prevent the head from falling out.
The opening width opened to the surfaces of the side plates 22c and 22d is set smaller than the depth side. Thus, the bolt mounting groove 3
5, 38, 39, 41, 42 are bolts 34, 36, 3
It has a function of guiding the heads 7 and 40 slidably and locking them in the axial direction of the bolt.

In FIG. 3, the angle 25 has a vertical part 25a and a horizontal part 25b integrally, and the vertical part 25a
Are closely contacted with the lower end of the side plate 22c, and are fixed by bolts 36 and nuts 44. On the other hand, the horizontal portion 25b
Is fixed to the upper surface of the support member 28 by bolts 45 and nuts 46.

3, 5 and 7, the auxiliary beam 23 is formed of a hollow extruded material having a vertically long rectangular cross-sectional shape, so that the upper plate 23a and the lower plate 23 are formed.
b, and a pair of left and right side plates 23c and 23d are integrally provided,
Further, floor plate supporting portions 23e and 23f that support the floor plate 24 together with the upper plate 23a are integrally provided on the widthwise side edge of the upper plate 23a over the entire length in the longitudinal direction. Left and right side plates 23
c, 23d, the flange material 26
The two bolt insertion holes 48 into which the bolts 47 for fixing the bolts are inserted are formed in upper and lower two stages, respectively. Bolt insertion holes 50 into which bolts 49 for fixing the floor plate 24 are inserted are formed at both longitudinal ends and the center of the floor plate support portions 23e and 23f, respectively. Such auxiliary beams 23 are arranged in parallel in the longitudinal direction of the passage 20 so as to be perpendicular to the main beams 22 at an interval of 1 m between the left and right main beams 22, and both ends are bolted to the main beam 22 via the flange member 26. 40
And a nut 55. Therefore, the main beam 22 and the sub beam 23 have a ladder shape when they are connected to each other. In addition, such a sub beam 23 is easily formed by extrusion molding.

As shown in FIGS. 5 and 8, the flange member 26 is formed in a crank shape in plan view, and has plate portions 26a and 26b facing each other in parallel, and one end of these plate portions 26a and 26b. And a pair of fixing portions 26e and 26f, which are connected to each other so as to be substantially perpendicular to the outside of the other end of each of the plate portions 26a and 26b. I have. Plate 26
a and 26b are formed in a size that can be fitted in the space of the sub beam 23, and the bolt insertion hole 53 into which the bolt 47 is inserted at one end side corresponds to the bolt insertion hole 48 of the sub beam 23. Is formed. The bolt insertion hole 53 is formed so as to be located between the connecting portions 26c and 26d. The pair of fixing portions 26e and 26f are plate portions 26a,
26b is in contact with the opening end face of the sub beam 23 in a state where it is fitted into the sub beam 23 and fixed by the bolt 47 and the nut 51, and the side plate 22d inside the main beam 22 is provided.
Is fixed by the bolt 40 and the nut 55.

3, 5 and 9, the floor plate 24 is composed of two floor members 24 A and 24 B which are formed so as to be substantially symmetrically divided in the width direction of the passage 20. And on the upper surface of the sub beam 23.

In FIG. 9 (a), one flooring material 24A
A plate-shaped main body 60 having substantially the same length as the main beam 22,
Bolt mounting portions 61 and 62 suspended from one end and the other end of the main body 60, and these bolt mounting portions 61 and 62
And a leg 63 suspended therebetween. The lengths of the bolt mounting portions 61 and 62 and the leg portion 63 in the height direction are set to be equal, and the lower end is supported in contact with the upper surface of the sub beam 23.

An engaging groove 64 having a depth substantially equal to the plate thickness of the main body 60 is formed on the upper surface of one end of the main body 60 where the bolt mounting portion 61 is vertically provided. A non-slip 65 made of a protruding body is integrally protruded from the surface of the main body 60 at a position corresponding to the bolt attachment portion 62 and the leg 63 and the other end thereof over the entire length of the main body 60. The left end of the main body 60 is supported by the main beam 22 by being superimposed on the upper surface of the left main beam 22 and engaged with the shallow groove 33 as shown in FIG. In this state, the upper surfaces of the main beam 22 and the floor member 24A form the same plane.

The bolt mounting portion 61 vertically provided at one end of the main body 60 includes a vertical plate portion 61a and the vertical plate portion 61a.
Bent portion 61b formed in an L-shape at the lower end of
And a falling-off preventing portion 61c formed by bending the lower end of the bent portion 61b. The bolt mounting portion 62 vertically provided near the other end of the main body 60 includes a vertical plate portion 62a,
A U-shaped bent portion 62b continuously connected to the lower end of the vertical plate portion 62a so as to open downward, and a detachment preventing portion 62c formed by bending both ends of the bent portion 62b so as to face each other. 62d, and the head of the bolt 49 is inserted into the bolt mounting grooves 35, 3 in a space formed by the bent portion 62b and the disengagement preventing portions 62c, 62d.
Like 8, 39, 41, and 42, they are housed so as to be slidable and lockable in the axial direction. The leg portion 63 is formed of an inverted T-shape and includes a vertical plate portion 63a and a horizontal plate portion 63b provided at a lower end of the vertical plate portion 63a so as to be orthogonal to the vertical plate portion 63a.

In FIG. 9B, the other floor material 24B
A plate-shaped main body 66 having substantially the same length as the main beam 22;
Bolt mounting portions 67 and 68 which are vertically provided near one end and the other end of the main body 66, and these bolt mounting portions 67 and
And a leg 69 vertically interposed between the legs 68.
The main body 66 and the bolt mounting portions 67 and 68 have the same length in the height direction, and are set to the same length as the main body 60 and the bolt mounting portions 61 and 62 of the one flooring material 24A.

At the surfaces of the main body 66 corresponding to the both ends and the bolt mounting portions 67, 68 and the legs 69, non-slip members 70 made of a projecting body are integrally provided over the entire length of the main body 65, respectively. . 9B, the left end of the main body 66 is overlapped with one of the floor materials 24A when the two floor materials 24A and 24B are connected in the width direction, and the engagement groove 6 is formed.
4 is engaged. On the other hand, the right end is superimposed on the right main beam 22 as shown in FIG. In this state, the main beam 22 and the floor members 24A, 2
The upper surface of 4B forms the same plane.

The bolt mounting portion 67 suspended from one end of the main body 60 includes a vertical plate portion 67a and a vertical plate portion 6a.
A bent portion 67b formed by bending an L-shape at the lower end of 7a
And a fall-off prevention portion 67c projecting substantially horizontally from the lower end of the bent portion 67b, and constitutes one bolt attachment portion together with the bolt attachment portion 61 of the one flooring material 24A.
That is, the bolt mounting portion 66 is provided with two floor materials 24A, 2A.
When 4B is connected in the width direction, the bolt mounting portion 61 of one flooring material 24A and the vertical plate portions 61a and 67a come into close contact with each other as shown in FIG. Construct the bolt attachment part and bend part 6
The head of the bolt 49 is slidably and axially in the space defined by the bolts 1b and 67b and the stopper portions 61c and 67c in the same manner as the bolt mounting grooves 35, 38, 39, 41 and 42. It is stored so that it can be locked.

The bolt mounting portion 68 vertically provided near the other end of the main body 60 includes a vertical plate portion 68a and the vertical plate portion 68.
a-shaped bent portion 68b continuously connected to the lower end of the bent portion 68a so as to open downward, and detachment preventing portions 68c and 68d formed by bending both ends of the bent portion 68b so as to face each other.
The bent portion 68b and the disengagement prevention portion 68c,
68d, the head of the bolt 49 is inserted into the bolt mounting grooves 35, 38, 39, 41, 4
As in the case of 2, it is housed slidably and lockable in the axial direction.

The leg 69 is formed in an inverted T-shape and includes a vertical plate 69a and a horizontal plate 69b provided at the lower end of the vertical plate 69a so as to be orthogonal to the vertical plate 69a. ing. The floor members 24A and 24B are easily formed by extrusion.

To attach the floor plate 24, first, the two floor materials 24A and 24B are joined in the width direction, and the left end of the other floor material 24B is overlapped with the one floor material 24A and engaged with the engagement groove 64. Then, the head of the bolt 49 is housed in the space between the bolt mounting portions 61 and 67, 62, 68, and is placed on the sub beam 23,
The left and right main beams 2 are connected to the ends of the floor members 24A and 24B on the side of the passage.
2 and engage with the shallow groove 33. Then, the floor plate 24 may be fixed on the main beam 22 and the sub beam 23 by inserting the bolt 49 into the bolt insertion hole 50 (FIG. 7) of the sub beam 23 and screwing the nut 70. When the floor plate 24 is mounted on the main beam 22 and the sub beam 23, the main beam 2
2 and the upper surface of the floor plate 24 form the same plane. When the upper surface of the main beam 22 is set to be flush with the upper surface of the floor plate 24, the width of the floor plate 24 can be reduced because the main beam 22 can be used as a part of the floor plate on which the worker can walk. Can be.

In FIGS. 3, 5 and 10, the column 29 is formed of a hollow extruded material, and is erected along the outer surfaces of the left and right main beams 22 at the same interval as the sub beams 23. Have been. The column member 29 includes a column main body 29a having a rectangular shape in plan view, and plate-shaped fixing portions 29b and 29c extending on both side edges of one side of the column main body 29a. Is in close contact with the outer side surface of the main beam 22 and is fixed by the bolt 37 and the nut 71. Therefore, each of the fixing portions 29b, 29c
Are formed with bolt insertion holes 73 into which the bolts 37 are inserted. Such a pillar 29 is easily formed by extrusion.

In FIG. 2, the middle crosspiece 30 is formed of a hollow extruded material having a concave cross-section in a plane perpendicular to the longitudinal direction, and is fixed to the inner surface of the pillar 29 in two upper and lower stages. The space between the left and right middle crosspieces 30 (effective passage width) is 510 mm
It is.

The handrail 31 is formed by a hollow extruded material having a substantially semicircular cross-sectional shape as shown in FIG. And a bottom portion 31b that closes an opening at the lower end of the curved portion 31a. Also, the bottom 31b
In the center in the width direction, an engaging portion 80 with the pillar 29 is provided. The engaging portion 80 includes a U-shaped bent portion 80a that opens downward, and slip-off preventing portions 80b and 80c formed by bending both ends of the bent portion 80a so as to face each other.
And is engaged with an engaging portion (not shown) provided on the upper surface of the column member 29 from the traveling direction of the passage.
1 is prevented from coming off above the pillar 29.

In the passage 20 having such a structure, the floor board 24 can be formed thin to reduce the weight. That is, in the conventional permanent passage shown in FIG. 12, since the floor plate 2 itself has a rigid frame structure to increase the strength, the thickness and weight of the floor plate 2 increase, and as a result, the passage itself also becomes heavy. there were. On the other hand, in the present invention, the main beam 2 made of a hollow extruded material is used.
2 is used as a strength member for supporting the load in the vertical direction, the main beams 22 support both ends of the floor plate 24 in the width direction, and a plurality of sub beams 23 made of a hollow extruded material in the longitudinal direction.
Therefore, there is no need to increase the strength by using the floor plate 24 as a rigid frame structure. In this case, the main body 60 of the floor members 24A and 24B,
66 receives a load vertically downward when the worker is on it,
Although the main beam 22 and the bolt mounting portion 6
1, 62, 67, 68 and the legs 63, 69 suppress downward deformation. Therefore, it is not necessary to increase the strength of the floor plate 24, and it can be formed thin to reduce the weight.

Further, since the main beam 22 and the sub beam 23 have a large section moment by increasing the section height without increasing the wall thickness, sufficient strength in the vertical direction can be obtained. In addition to suppressing the weight increase due to these members, the span of the support member 28 and the length of the floor plate 24 can be extended to 6 m, which is the same as the length of the passage made of steel. Therefore, the number of the support members 28 can be reduced, and the load on the bridge can be reduced.

Incidentally, the span of the supporting member 28 is set to 6 m, and the applied load (equally distributed load) applied to the passage 20 is 350
When the amount of deflection when Kg / m ² was measured, the amount of deflection δ was 11.5 mm, which was 1/300 (6000) of the span.
(300 = 20 mm) or less. Further, no permanent deformation of each component was observed.

The main beam 22, the sub beam 23 and the floor plate 24
The floor unit 21 can be assembled at a factory. After the assembled floor unit 21 is transported to a construction site and installed on the support member 28, the column member 29 is attached to the main beam 22.
Erected on the outer surface of
9, it is easy to construct the passage 20 on site and can be performed in a short time. In addition, since the floor unit 21 is transported in a state where the pillar 29 is not attached, the transport efficiency can be improved.

Further, since the upper surface of the main beam 22 forms the same plane as the floor plate 24 and forms a part of the passage, the width of the floor plate 24 can be reduced.

Further, since the handrail 31 is attached to the upper surface of the pillar 29, the finger does not hit the pillar 29 when the hand is moved along the handrail 31 to the end of the handrail. In addition, since the upper surface of the handrail 31 is curved in a substantially semicircular shape, there is little risk of injury even if the worker hits the handrail.

Further, in the present invention, it is not necessary to form a screw hole into which a bolt is screwed in the component of the passage 20, so that corrosion from the screw hole due to contact between dissimilar metals can be prevented. Also, since the components are anodized and the bolts are dacro-treated,
The dissimilar metals do not come into direct contact with each other, corrosion can be further prevented, and the durability of the passage 20 can be improved.

[0047]

As described above, according to the permanent bridge lower passage according to the present invention, since both ends in the width direction of the floorboard are supported using the main beam made of a hollow extruded material,
There is no need to make the floorboard a strength member of the ramen structure. Therefore, it is possible to reduce the weight of the floorboard by forming it into a thin plate shape, and to further reduce the weight of the permanent passage itself. In addition, the conventional aluminum alloy permanent passages have insufficient strength, so that the length of the floor plate is shorter than that of the steel floor plate, and it is necessary to support not only both ends but also the middle portion in the longitudinal direction with the support member. Therefore, the number of parts of the supporting member was increased, and the load on the bridge was large.However, in the present invention, the length of the floor plate was the same as that of the steel permanent passage, and only the both ends were supported. In addition, the amount of bending can be suppressed to the same amount of bending as a steel floor plate. Therefore, the number of parts of the support member can be reduced, and the load on the bridge can be reduced.

In the present invention, since the pillars are connected by the middle crosspiece, the strength of the pillars can be increased. Further, since the handrail is provided on the upper surface of the pillar, the finger does not hit the pillar even if the hand is moved along the handrail.

[Brief description of the drawings]

FIG. 1 is an external perspective view showing an embodiment of a permanent passage under a bridge according to the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is an enlarged sectional view taken along line III-III of FIG. 1;

FIG. 4 is a side view of a main part of the passage.

FIG. 5 is an enlarged bottom view showing a part of a main part of the passage in a broken view.

FIG. 6 is a sectional view of a main beam.

FIG. 7 is a sectional view of a sub beam.

FIG. 8 is a sectional view of a flange material.

FIGS. 9A and 9B are front views of a floor material.

FIG. 10 is a sectional view of a column member.

FIG. 11 is a front view of a handrail.

FIG. 12 is an external perspective view of a conventional bridge lower permanent passage.

[Explanation of symbols]

Reference numeral 20: permanent passage under the bridge, 21: floor unit, 22: main beam, 23: sub beam, 24: floor plate, 24A, 24B: floor material,
25 ... Angle, 26 ... Flange material, 28 ... Support member,
29 ... pillar material, 30 ... middle crosspiece, 31 ... handrail.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Hideo Tachibana 2-2-2-20 Higashishinagawa, Shinagawa-ku, Tokyo Nikkei Shape Materials Co., Ltd. (72) Inventor Hiroshi Karube 3-8-25 Higashi, Kashiwa-shi, Chiba 72) Inventor Kazuo Tanioka 8-2-603 Kitakaruizawa, Nishi-ku, Yokohama-shi, Kanagawa-ken

Claims (3)

[Claims] 1. A pair of left and right main beams made of an aluminum alloy hollow extruded member disposed in parallel on a support member along a bridge, and a hollow extrusion made of an aluminum alloy connecting the main beams in a ladder shape. A permanent passage under a bridge, comprising: a plurality of sub beams made of a material; and a floor plate made of an extruded aluminum alloy material laid on the sub beams. 2. The permanent bridge lower passage according to claim 1, wherein a plurality of pillars are attached to an outer surface of the main beam, and these pillars are connected to each other by a middle crosspiece. . 3. A permanent bridge lower part passage according to claim 2, wherein a handrail is attached to an upper surface of the column member.