JP2009167791A - Construction method of upper deck type suspension floor slab bridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for safely and inexpensively constructing an upper deck type suspension floor slab bridge by securing stability in the lateral direction when the upper deck type suspension floor slab bridge is constructed. <P>SOLUTION: A cable 12 is extended between two abutments 1, 2 standing face to face so that a concrete slab unit comprising a concrete slab and supporting posts 52 standing on it may be supported by the cable. Then, a plurality of the units are sequentially arranged along the cable. The top parts of the units are connected to the abutment 2 on one side and the top parts of the supporting posts of the adjacent units are connected in sequence. Thus, lateral displacement is restrained by the rigidity of the connected members and sway of the top parts of the supporting posts is restricted. The members connecting the top parts of the supporting posts are preferably truss members resisting the horizontal force. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an upper-floor type suspension floor slab bridge, which is a type of bridge, that is, a thin concrete plate-like member supported by a cable is stretched in a state in which deflection occurs, and a column is placed on the suspension floor slab. It is related with the construction method of the bridge which supports the upper girder for standing up and forming a flat road surface on it.

As disclosed in Patent Document 1, for example, an upper-floor type suspended floor slab bridge is constructed by suspending a suspended floor slab made of a thin concrete plate-like member between two opposing abutments, and a column is erected thereon. In this way, the upper girder is supported. The suspended floor slab is supported by a cable and prestressed in the axial direction, and is a sufficiently thin member that does not crack even when bending deformation occurs due to a live load.
In general, a suspended floor slab bridge is used to pave the upper surface of the suspended floor slab to form a road surface. In this type of bridge, a vertical gradient is generated on the road surface due to the deflection of the suspended floor slab. For this reason, it is difficult to make a bridge through which vehicles pass, and it is used only for footbridges.
On the other hand, since the upper road type suspension floor slab bridge has an upper road girder, the longitudinal gradient of the road surface can be arbitrarily set, and the versatility is high. Moreover, the both ends of a suspended floor slab can be connected with an upper road girder, the tensile force which acts on a suspended floor slab can be transmitted to an upper road girder, and it can also act as a compressive force on an upper road girder. As a result, the horizontal reaction force acting on the abutment or pier is reduced, and the stability of the abutment and the like in the completed system can be improved.

An upper-floor type suspended floor slab bridge is generally constructed by the following process.
First, a cable is stretched between two abutments facing each other, supported by the cable, and a precast concrete plate is arranged between the abutments. Then, a pillar is erected on the concrete plate. This strut is previously combined with the concrete plate in advance, and is disposed at a predetermined position on the cable together with the concrete plate, thereby enabling efficient construction. When the struts are provided, they form upper girder connecting these tops. The upper girder may be formed of concrete cast on site by assembling a support on a suspended floor slab, but the construction period can be shortened by using a segment made of precast concrete.
Such an upper suspension type slab bridge is constructed with a member having a smaller cross section than a general girder bridge. Therefore, it can be constructed in a short construction period without using a large erection machine or the like, that is, a supporting work, a cable crane, a large heavy machine, etc., and thus has an advantage that it can be constructed at a low cost.

Japanese Patent Application No. 2000-33388

However, the construction of the above-described upper suspension type slab bridge has the following problems.
A cable is stretched between the abutments, and the concrete plate is supported on the cable, and at the stage where the support column is erected on the concrete plate, the lateral stability may be insufficient. That is, the concrete plate supported by the cable in a state in which the deflection has occurred and the support column erected on the slab are easily swayed in the horizontal direction, and it is difficult to restrain the swaying due to natural phenomena such as wind. For this reason, the structural system during construction tends to become unstable.

  When the upper girder is formed, the tops of the columns are connected and both ends of the upper girder are constrained by the abutment or pier, sufficient stability is obtained by the lateral rigidity of the upper girder, but the upper girder is formed There is a need for means to ensure lateral stability in the construction stage up to the above.

  The present invention has been made in view of the circumstances as described above, and its purpose is to ensure sufficient stability in the lateral direction of the strut during the construction of the upper-floor type suspension floor slab bridge, safely and at low cost. It is to build an upper-floor type suspended floor bridge.

In order to solve the above-mentioned problems, the invention according to claim 1 is characterized in that the concrete of a unit comprising a concrete plate and a support column erected on the cable is stretched between two opposing abutments or piers. A plate is supported by the cable, and for the unit supported by the cable adjacent to the abutment or the pier, the top of the column and one of the abutment or the pier are connected to perform lateral movement of the top of the column. In addition, a plurality of units are sequentially arranged along the cable from a position adjacent to the constrained unit, and the tops of the columns of the arranged units are sequentially connected to the tops of the columns of the adjacent units. Te, restraining the lateral movement of the strut top of the unit newly arranged, supported on said post, continuous between positions on the two said abutment or pier facing That Raise digit is formed, then, provides a method for constructing a Raise formula Tsuridoko slab bridge, characterized in that a step of the Tsuridoko plate continuous with Da設 concrete between a plurality of said concrete panel.

  In this method of constructing an upper suspension type slab bridge, the unit supported by the cable adjacent to the abutment or pier is in a stable state with respect to lateral shaking because the top of the column is connected to the abutment or pier. . Further, in the other units which are supported by the cables sequentially adjacent to this unit, the tops of the respective columns are sequentially connected, and the lateral displacement is restricted by the abutment or the pier. Therefore, even in the stage before the upper beam is formed, the unit is supported in a laterally stable state on the cable.

The invention according to claim 2 is the construction method of the upper-floor type suspended floor slab bridge according to claim 1, wherein the member that connects the tops of the columns projects in a cantilevered manner from the abutment or the pier, A truss that restrains the displacement in the horizontal direction with respect to the abutment or the pier is configured.

  In this method, the member that connects the top of each column to the abutment or the pier constitutes a truss and has a large rigidity in the horizontal direction. And it protrudes in a cantilever form from an abutment or a pier, and a horizontal force is transmitted to the abutment or the pier. Therefore, it is possible to reduce the lateral displacement with a lightweight member, and the lateral stability of the support column can be improved.

According to a third aspect of the present invention, in the construction method of the upper suspension type slab bridge according to the first or second aspect, one end is fixed to an anchor block provided at a lateral position of the abutment, and the other end is the Auxiliary wires fixed to a concrete plate supported by a cable are provided on both sides of the axis of the bridge girder, and the auxiliary wires are arranged on both sides of the axis of the bridge girder and stretched in a direction along one straight line. The lateral displacement of the plate shall be constrained.

  In this method, the concrete plate supported by the cable is restrained from shaking in the lateral direction together with the cable in a state of being bent. Accordingly, the unit is restrained from being displaced in the lateral direction both at the top of the column and at the lower concrete plate, and the stability against lateral shaking is improved.

As described above, in the construction method of the upper-floor type suspended floor slab bridge according to the present invention, the top of the unit is connected to one abutment or pier, and the vibration is also restrained by restraining the lateral displacement by the rigidity of the connected member. Suppress. Thereby, it is possible to perform the construction in a stable state while suppressing the lateral shaking at the time of erection. Furthermore, by using a truss that resists the force in the horizontal direction as a member that connects the top to an abutment or the like, even in the case of a lightweight member, the lateral stability can be effectively improved.

It is a schematic side view which shows an example of the upper type suspension floor slab bridge constructed | assembled by the method which is one Embodiment of this invention. It is sectional drawing of the upper-path-type suspension floor slab bridge shown in FIG. It is an enlarged view of the edge part of the upper-path-type suspension floor slab bridge shown in FIG. It is the schematic which shows the process of constructing the upper-path type suspension floor slab bridge shown in FIG. It is the schematic which shows the process of constructing the upper-path type suspension floor slab bridge shown in FIG. It is a schematic sectional drawing which shows the state which temporarily fixed to the abutment the end block to which a suspended floor slab and an upper road girder are connected in the process of constructing the upper road suspended floor slab bridge shown in FIG. It is sectional drawing which shows the fixing state of the cable in erection. It is the schematic which shows the process of constructing the upper-path type suspension floor slab bridge shown in FIG. It is the schematic which shows the process of constructing the upper-path type suspension floor slab bridge shown in FIG. It is a schematic perspective view which shows the unit for constructing | assembling the upper-path type suspended floor slab bridge shown in FIG. It is a schematic plan view of the state shown in FIG. It is a schematic plan view which shows the tension state of the auxiliary wire which prevents a cable from rolling. FIG. 10 is a schematic plan view of the state shown in FIG. 9. It is a schematic perspective view of the precast concrete segment used in order to form an upper road girder. It is the schematic which shows the process of constructing the upper-path type suspension floor slab bridge shown in FIG. It is the schematic which shows the process of constructing the upper-path type suspension floor slab bridge shown in FIG. It is the schematic which shows the process of constructing the upper-path type suspension floor slab bridge shown in FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic side view of an upper suspension type slab bridge constructed by a method according to an embodiment of the present invention. 2 is a cross-sectional view, and FIG. 3 is an enlarged view of an end portion.
The upper-floor type suspended floor bridge is constructed between two abutments 1 and 2 and includes concrete end blocks 3 and 4 supported on the abutments 1 and 2 through fences 5 and 6. The suspended floor slab 7 stretched between the end blocks 3 and 4, a plurality of columns 52 erected on the suspended floor slab 7, and the upper path formed to be continuous with the end blocks 3 and 4. The main part is composed of the girder 9.

  The abutments 1 and 2 are constructed of reinforced concrete on a strong ground 29 at a position where the bridge is constructed, and are firmly fixed to the ground 29 or the rock by earth anchors 10 and 11 at the time of construction. After the suspended floor slab 7 and the upper girder 9 are completed, the earth anchors 10 and 11 become unnecessary and can be removed, but may be left as they are.

  As the ridges 5 and 6, rubber ridges, cast ridges and the like can be used. These eaves 5 and 6 support the girder so that they can rotate around a horizontal axis perpendicular to the axis of the bridge, and one of the eaves 5 and 6 that support both ends of the girder is one of the bridges. The horizontal movement in the axial direction is restricted, and the other is allowed to move. Horizontal movement in the direction perpendicular to the axis of the bridge is constraining both ridges 5 and 6.

  The end blocks 3 and 4 may be made of cast-in-place concrete, or precast concrete that has been manufactured in advance at a factory or the like. As shown in FIG. 3, an upper road girder 9 continuous between both is joined to the upper part of these end blocks 3 and 4, and a suspended floor slab 7 is joined to the lower part. Then, both ends of the cable 12 that supports the suspended floor slab 7 are fixed to these end blocks 3 and 4, respectively.

  The suspended floor slab 7 is a thin plate member made of concrete, is continuous between the two end blocks 3 and 4, and is supported by the tensile force of the cable 12 in a state in which deflection occurs. This suspended floor slab 7 is placed so as to connect a plurality of precast concrete slabs created at a production yard near the factory or the site, and between these precast concrete slabs and the end blocks 3 and 4. Made with cast-in-place concrete.

  The cable 12 includes a plurality of first steel strands 13 and a plurality of second steel strands 14, and the first steel strands 13, as shown in FIG. It accommodates in the groove | channel 7a formed in the lower surface of this, and supports the suspended floor slab 7 from the lower side. The first steel stranded wire 13 is coated with a synthetic resin, and a tubular fixing body 15 made of steel is pressure-bonded to the end portion. A screw thread is formed on the outer peripheral surface of the fixing body 15 and can be fixed to the end blocks 3 and 4 of the concrete by screwing a nut 17.

  The second steel strand 14 is inserted into a sheath embedded in the concrete of the suspended floor slab 7, and both ends are also fixed to the end blocks 3 and 4.

  As shown in FIG. 1, the support column 52 is configured to rise obliquely upward from the upper surface of the suspended floor slab 7 and to support the upper road girder 9. Two struts 52 a and 52 b that are inclined in opposite directions in the bridge axis direction are raised from substantially the same position of the suspended floor slab 7, and these struts 52 form a warren truss together with the suspended floor slab 7 and the upper road girder 9. Yes.

  The upper girder 9 is placed so as to be integrated with the segment 20 made of precast concrete supported on the top of the column 52, and is continuous between the plurality of precast concrete segments and between the precast segments and the end blocks. It is composed of cast-in-place concrete and a floor slab 21 formed of cast-in-place concrete on these. And reinforcement with the reinforcing bar is made so that it can fully endure the bending moment and the shearing force due to its own weight or live load.

Next, it is one Embodiment of the invention which concerns on this application, Comprising: The method to construct | assemble the said upper-path type suspended floor slab bridge is demonstrated.
First, as shown in FIG. 4, abutments 1 and 2 are constructed on both sides of the position where the bridge is constructed. The abutments 1 and 2 are firmly fixed to the ground 29 or the rock by the earth anchors 10 and 11 so as to resist a large horizontal force. Then, the end blocks 3 and 4 are formed on the abutments 1 and 2 via the eaves 5 and 6, and these are temporarily fixed to the abutments 1 and 2. As shown in FIG. 6, the temporary fixing of the end blocks 3, 4 is performed by inserting temporary fixing blocks 30, 31, 32, 33 in front and sides of the flanges 5, 6, Tighten with 36.

  As shown in FIG. 4, a suspension scaffold 8 for facilitating the work is bridged between the two abutments 1 and 2. This suspended scaffold 8 is used for construction of the suspended floor slab 7 and is stretched below the position where the suspended floor slab 7 is provided. The suspension scaffold 8 is constructed in such a manner that a wire is stretched between the abutments 1 and 2, and the scaffold plate is supported by the wire in a state where the deflection is generated between the abutments 1 and 2. Further, reaction force bases 46 and 47 are provided in the vicinity of both abutments 1 and 2, respectively, and a ceiling cable 19 for material conveyance is stretched between these reaction force bases 46 and 47.

Thereafter, the cable 12 is stretched between the end blocks 3 and 4. The cable 12 to be stretched here is only the first steel strand 13 and is inserted into the sheath embedded in the end blocks 3 and 4 as shown in FIG. An extension cable 37 is added to the fixed fixing body 15 by the coupler 34 and fixed to the abutment 1 by the nut 18. As a result, the reaction force acting from the cable 12 during installation is borne on the abutment 1 so that no reaction force acts on the end block 3. The fixing body 15 is screwed with a nut 17 to fix the cable 12 by applying a reaction force to the end blocks 3 and 4 in the completed system.
Note that the rear part of the abutment 1 is reinforced by the PC steel material 38 in the vertical direction so that excessive tensile stress is not generated in the rear cross section of the abutment 1 when the reaction force from the extension cable 37 is applied.

  Next, as shown in FIG. 4, a part 9 a of the upper road girder is formed so as to project from one end block 4 in a cantilever shape with a predetermined length. This part of the upper girder is formed by assembling the reinforcing bars on the support and placing concrete. Thereafter, as shown in FIG. 5, a unit 50 comprising a precast concrete slab of a predetermined length constituting the suspended floor slab 7 and a plurality of struts joined to the upper surface is lifted by a portal crane 28 or the like, and this is suspended from the ceiling cable 19 Are suspended and supported, and sequentially transported to a predetermined position and arranged on the cable 12. The first unit 50 is connected and fixed to a portion 9a protruding from the end block 4 of the upper girder. As shown in FIG. 8, the units 50 arranged sequentially are connected to the top of the units 50 arranged earlier and the tops of the columns, and the lateral displacement is restrained by one abutment 2 through a member connecting them. Is done.

Here, the unit 50 will be described with reference to FIG.
This unit 50 is formed in a production yard provided near a factory or a construction site, and has a precast concrete plate 51 to be a suspended floor plate 7 at a lower portion, and four support columns 52 made of steel pipes. It is raised obliquely upward from the upper surface of the precast concrete plate 51. These steel pipes are provided so that the distance between the ends of the steel pipes opens from the lower end in the axial direction and the width direction of the bridge, and the upper ends of the steel pipes are connected to each other by a temporary fixing member 53 so that the position does not change relatively. It is restrained by. Further, the lower portion of the column 52 is firmly fixed by an anchor (not shown) embedded in the precast concrete plate 51 so that the force is reliably transmitted between the concrete plate 51 and the column 52. . In addition, the code | symbol 54 in FIG. 10 is a convex part provided on the precast concrete plate in order to connect a support | pillar, and the code | symbol 55 is a cross beam for reinforcing the junction part with the support | pillar of a precast concrete plate.

  Further, two steel mold members 56 and 57 are attached in parallel to the upper portion of the unit 50 so as to project in the axial direction of the bridge, and connect the top portion of the column 52 and the portion 9a projecting from the end block 4. It is a member that connects the tops of the members or the columns of adjacent units. These steel mold members 56 and 57 continue in the axial direction of the bridge when connected to the adjacent units 50 and function as rail-like members.

  11 is a plan view showing a state in which the units 50 are arranged on the cable 12, and is a view of the state shown in FIG. 8 as viewed from above. As shown in this figure, steel mold members 56 and 57 provided on the upper portion of the unit 50 are connected between the units 50, and an oblique connecting member 58 is provided between the two steel mold members 56 and 57 in an oblique direction. A horizontal truss is formed. As a result, the horizontal force acting on the unit 50 is transmitted to the abutment 2 by the rigidity of the truss and restrains the displacement by restraining the lateral displacement.

When the unit 50 is disposed at a predetermined position on the cable 12, side wires 40 are stretched on both sides of the bridge axis in order to constrain lateral displacement of the column top. As shown in FIG. 11, the side wire 40 has one end coupled to anchor blocks 41, 42, 43, 44 provided on the sides of the abutments 1, 2 and the other end coupled to the top of the column 52. . And the displacement to the horizontal direction of a support | pillar top part is restrained by introduce | transducing tension to both sides. These side wires 40 may be stretched from two anchor blocks provided on both sides of one abutment. However, as shown in FIG. It is desirable to stretch from the side. The side wires 40 may be stretched with respect to each of the units 50. However, the side wires 40 are stretched for each of a plurality of connected units 50, and these are combined to restrain lateral displacement. Also good.
The anchor blocks 41, 42, 43, 44 are firmly fixed to the ground 29 by the ground anchor 45 so as to resist the tensile force of the side wire 40, and are almost the same height as the upper girder 9 is provided. Provided.

Furthermore, the auxiliary wire 60 is constrained to restrain the cable 12 in the state of deflection and the precast concrete plate 51 supported by the cable 12 from shaking in the lateral direction. As shown in FIGS. 8 and 12, the auxiliary wire 60 is connected to substantially the lowest point of the cable 12 in which the deflection has occurred and is stretched on both sides, and the wire 60a stretched on one side. The other end is coupled to an anchor block 63 provided below the lowest point of the cable 12 on the side of the abutments 1 and 2. The other wire 60b is coupled to an anchor block 42 provided at the same height as the upper beam girder 9 on the side of the opposite abutment. The wires 60a and 60b on both sides are stretched so as to be substantially on the same straight line. Accordingly, the lateral displacement of the cable 12 and the precast concrete plate 51 is restrained, and the precast concrete plate 51 is hardly subjected to a vertical force.
In this embodiment, only one auxiliary wire 60 is stretched on both sides, but can be stretched in other directions as needed.

  In this way, the units 50 are arranged while being sequentially fixed, and when the arrangement of all the units is completed as shown in FIG. 9, the sheath 14 in which the second steel strand 14 is embedded in the precast concrete plate 51 below the unit 50. The both ends are fixed to the end blocks 3 and 4. A fixing body (not shown) is fixed to both ends of the second steel strand 14 in the same manner as the first steel strand, and a nut is screwed into a screw thread formed on the fixing body. It can be fixed to concrete.

  As shown in FIGS. 9 and 13, when all the units 50 are arranged at predetermined positions on the cable 12 and the tops of all the units 50 are connected, a pair of rail-like members 56 ′, 57 ′ are attached to the upper part of the units. Is completed. The rail-like members 56 'and 57' are used to feed a precast concrete segment 20 for forming the upper beam 9 as shown in FIG. At this time, a feeding device (not shown) having a rolling element such as a roller is placed on the rail-like members 56 ′ and 57 ′ so that the feeding can be easily performed. The precast concrete segment 20 is supported on the feeding device and conveyed on the rail-like members 56 ′ and 57 ′.

  As shown in FIG. 14, the precast concrete segment 20 includes a main girder portion 23 for increasing rigidity in the bridge axis direction, and a cross beam connecting two main girder portions provided on the left and right along the bridge axis. Part 24. The main girder 23 has an opening 23a at the bottom where the upper end of the column of the unit is joined, is a box-shaped member that is long in the direction of the bridge axis, and both ends are adjacent to the precast concrete segment 20 ′. Reinforcing bars (not shown in the figure) for joining to are projected.

  As shown in FIG. 15, when all the precast concrete segments 20 are sent out along the rail-like members and arranged at predetermined positions, the precast concrete segments 20a and the precast concrete segments and the cast-in-place concrete are already formed. Concrete is placed between the upper girder 9a or the end block 3 and connected to each other. Further, concrete is cast on the main girder 23 and between the two main girder parts to form the floor slab 21, and the upper girder 9 is continuous between the two end blocks 3 and 4.

The floor slab 21 is formed as follows.
On the arranged precast concrete segments 20, a concrete plate into which prestress is introduced is laid out in a pretensioning manner, and a reinforcing bar is assembled thereon. And this concrete board is used as a formwork, and concrete is cast so that it may become one. That is, the concrete panel into which the prestress is introduced becomes a part of the floor slab.
By forming the floor slab 21 by the process as described above, it is possible to omit the process of installing and removing the formwork for placing the concrete of the floor slab, and the construction period can be shortened.

When the upper girder 9 is constructed as described above, and the upper girder 9 continuous between the two end blocks 3 and 4 is formed as shown in FIG. 16, the upper girder 9 has a large lateral rigidity. Thus, the lateral displacement and shaking are significantly reduced, and the stretched side wires 40 and auxiliary wires 60 can be removed to restrain the lateral displacement during installation. Further, the rail-like members 56 ′ and 57 ′ that have connected the units 50 can also be removed. Further, the ceiling cable 19 and the portal crane 28 used for erection are also removed.

  Subsequently, the concrete plate 51 supported by the cable 12 (first steel strand 13) is connected to form a suspended floor plate 7 continuous between the end blocks 3 and 4. In this step, concrete is first placed so as to connect the precast concrete plates 51 of the adjacent units 50, and the precast concrete plates 51 are connected. Thereafter, concrete is placed between the both end blocks 3 and 4 and the precast concrete plate 51. After the concrete placed on site is hardened and the suspended floor plate 7 continues between the end blocks 3 and 4, the second steel strand 14 inserted through the sheath in the precast concrete plate 51 is tensioned first. Thus, axial prestress is introduced into the suspended floor slab 7. The second steel strand 14 is fixed to the end blocks 3 and 4.

  Next, the nut 18 holding the extension cable 37 connected to the first steel strand 13 to the abutments 1 and 2 is loosened and screwed to the fixing body 15 at the end of the first steel strand 13. The end block 3, 4 is caused to bear the tensile force of the first steel strand 13 by the nut 17. As a result, the reaction force of the first steel strand 13 is transferred from the abutments 1 and 2 to the end blocks 3 and 4 and transmitted from the end blocks 3 and 4 to the upper beam 9 as an axial force. As a result, the suspended floor slab is simply supported at both ends as shown in FIG. That is, the tensile force acting on the suspended floor slab 7 and the compressive force acting on the upper girder 9 are offset, and a so-called self-contained structure system in which no horizontal force acts on the abutments 1 and 2 is obtained.

  Thereafter, a pavement 71 is applied on the upper girder 7 and a rail 72 is attached to complete the upper road type suspended floor slab bridge.

1, 2 Abutment 3, 4 End block 5, 6 沓 7 Suspended floor slab 7a Suspended floor slab groove 8 Suspended scaffold 9 Upper girder 10, 11 Earth anchor 12 Cable 13 First steel strand 14 Second steel strand 15 Fixing bodies 17 and 18 Nut 19 Ceiling cable 20 Precast concrete segment 21 Floor slab 22 Transport steel mount 23 Main girder 23a Main girder opening 24 Horizontal girder 28 Gate-type crane 29 Ground 30, 31, 32, 33 Temporary Fixing block 34 Coupler 35, 36 Temporary fixing steel material 37 Extension cable 38 PC steel material 40 Side wire 41, 42, 43, 44 Anchor block 45 Ground anchor 46, 47 Reaction force table 50 Unit 51 Precast concrete plate 52 Support column 53 Temporary fixing member 54 convex portions 55 cross beams 56 and 57 steel material 56 ', 57' rail-like member 58 diagonally connecting member 60 complement Wire 63 the anchor block 71 pavement 72 railing

Claims (3)

Stretch a cable between two opposite abutments or piers,
Supporting the concrete plate of the unit consisting of a concrete plate and a column erected on the concrete plate by the cable,
For the unit supported by the cable adjacent to the abutment or the pier, the top of the column and one of the abutment or the pier are connected to restrain the lateral movement of the top of the column,
Further, a plurality of units are sequentially arranged along the cable from a position adjacent to the constrained unit, and the tops of the columns of the arranged units are sequentially connected to the tops of the columns of the adjacent units. Restrain the lateral movement of the top of the columns of units arranged in
Forming an upper girder that is supported on the strut and is continuous between the positions on the two abutments or piers facing each other;
Thereafter, a method of constructing an upper-floor type suspended floor slab bridge, comprising performing a step of placing concrete between the plurality of concrete slabs to form a continuous suspended floor slab. The member that connects the tops of the columns constitutes a truss that projects in a cantilevered manner from the abutment or the pier and restrains the horizontal displacement of the tops of the columns with respect to the abutment or the piers. The construction method of the upper-floor type suspended floor slab bridge according to Item 1. One end is fixed to an anchor block provided at a side position of the abutment, and the other end is provided with auxiliary wires fixed to a concrete plate supported by the cable on both sides of the axis of the bridge girder. The upper-floor type suspended floor slab according to claim 1 or 2, wherein a wire disposed on both sides of the axis is stretched in a direction along one straight line to restrain lateral displacement of the concrete slab. How to build a bridge.

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