JP6655746B2 - Bridge structure and floor slab replacement method - Google Patents

Description

  The present invention relates to a bridge structure and a method of replacing a floor slab.

  In the case of a bridge used for a highway or the like, it may be necessary to replace a slab of an aging road. Conventionally, when replacing a RC slab (reinforced concrete slab) of a bridge with a new slab, the existing reinforced concrete slab is first removed. Next, after the main girder upper flange of the main girder is completely smoothed, the studs are struck again, and when replacing the RC slab with a steel slab, a bolt hole is made in the main girder upper flange of the main girder. Or so.

  However, the conventional method has the following problems. (1) Removing reinforced concrete slabs with studs is very labor and time consuming. (2) When removing concrete between studs, noise, vibration and dust problems may occur. (3) When the reinforced concrete slab is completely removed, buckling may occur at the upper flange of the main girder, especially in the case of a composite slab. (4) When the reinforced concrete slab is removed, the dead load on the bridge is reduced to less than half, the deflection of the girder is reduced, and various dimensional adjustments are required to maintain the original route plan height. (5) If a floor slab is newly constructed according to the current standards, the weight will be greater than the original structure. For that purpose, it is necessary to reinforce the girder, the bridge pier and, in some cases, the pile (it is necessary to increase the width as well as the thickness).

  As an example of a method of replacing a floor slab of a bridge for solving such a problem, a method described in Patent Literature 1, for example, is known. In the floor slab replacement method described in Patent Document 1, in order to replace a reinforced concrete slab supported and laid on a main girder of a bridge with a steel slab, the steel slab is disposed at a position where the reinforced concrete slab has been removed. In the method of replacing a floor slab of a bridge, a floor slab support bracket is attached to the main girder at an appropriate interval below the reinforced concrete slab, and a reinforced concrete slab of a portion located on an upper flange of the main girder is removed. The remaining portion is removed to provide a remaining portion in the upper flange portion of the main girder, and in place of the removed reinforced concrete floor slab, the horizontal portion of the steel slab having a horizontal rib arranged to avoid the remaining portion is provided. A rib is provided, and the horizontal rib is mounted on the floor slab support bracket.

JP-A-2006-194215

However, in the floor slab replacement method described in Patent Literature 1, since the floor slab support bracket is attached to the web of the main girder by welding or the like, it takes time and effort to attach the floor slab support bracket, and the steel slab needs to be mounted. Since the horizontal rib is attached to the floor slab support bracket by welding or the like, it takes time to attach the horizontal rib.
The horizontal ribs of the steel slab are placed on the slab support bracket and attached to the slab support bracket. Basically, the slab support bracket is attached to the main girder as a cantilever. . Therefore, the floor slab support bracket that supports the weight of the steel slab needs to have a large strength. In addition, since it is difficult to design the horizontal rib as a continuous beam, a larger cross section may be required. Further, since the main girder is attached to the main girder only via the floor slab support bracket, it is difficult to transmit a shearing force between the main girder and the steel slab in the bridge axis direction. Therefore, it is difficult to form a bridge having an integrated structure in which the steel slab and the main girder are combined, and there is a possibility that the strength of the bridge may be insufficient.
In addition, if the height of the horizontal ribs rises due to a decrease in the deflection of the bridge when the concrete slab is removed because the horizontal ribs are placed on the brackets, it is not possible to adjust the position of the horizontal ribs in the downward direction. It may be possible.

  The present invention has been made in view of the above circumstances, and it is possible to easily and firmly connect a horizontal rib of a steel deck to a main girder web, secure rigidity and strength as a bridge, and furthermore, The bridge structure and the method of replacing the slab can be combined with the girder and the slab by reliably transmitting the shearing force in the bridge axis direction between the slab and the bridge, and also making it easy to adjust the position of the horizontal ribs during construction. The purpose is to provide.

In order to achieve the above object, the bridge structure of the present invention is a bridge structure constituted by replacing a part of a reinforced concrete slab supported and laid on a main girder of the bridge with a steel slab. hand,
Of the reinforced concrete floor slabs, the remaining reinforced concrete remaining except for the portion provided on the upper surface side of the main girder upper flange of the main girder,
In the reinforced concrete slab, a removing portion formed by removing a portion other than a portion provided on the upper surface side of the main girder upper flange of the main girder, a steel slab arranged to cover the remaining reinforced concrete. Prepared,
The steel deck has lateral ribs arranged in the bridge width direction on the lower surface side of the deck plate,
At least a part of one end face or both end faces in the bridge width direction of the transverse rib faces a web surface of a main girder web of the main girder closest thereto,
The cross rib is rigidly connected to the main girder web closest to the end at the bridge width direction end of the cross rib,
The main girder and the steel deck are connected by a shear force transmitting member that transmits a shear force in a bridge axis direction.

Further, the bridge floor slab replacement method of the present invention is a bridge floor slab replacement method for replacing a part of a reinforced concrete floor slab supported and laid on a main girder of the bridge with a steel slab,
The steel deck has horizontal ribs arranged in the bridge width direction on the lower surface side of the deck plate, and at least a part of one end surface or both end surfaces in the bridge width direction of the horizontal ribs is the closest main girder. It faces the web surface of the main girder web,
By removing a portion of the reinforced concrete slab other than the portion provided on the upper surface side of the main girder upper flange of the main girder, a removing portion is provided and the remaining reinforced concrete is left on the upper surface side of the main girder upper flange. Reinforced concrete slab removal process,
In the removing section, a steel slab arranging step of arranging a steel slab so as to cover the remaining reinforced concrete,
A transverse rib rigid connection step of rigidly coupling the transverse rib to the main girder web closest to the end at the end of the transverse rib;
A steel slab coupling step of coupling the main girder and the steel slab with a shear force transmitting member that transmits a shear force in a bridge axis direction;
It is characterized by including.

In the present invention, the steel deck is disposed in the bridge width direction on the lower surface side of the deck plate, and at least a part of one end surface or both end surfaces in the bridge width direction is a web surface of the main girder web of the main girder closest thereto. And the transverse rib is rigidly connected to the main girder web closest to the end at the bridge width direction end of the transverse rib. Since the ends of the transverse ribs of the plate are rigidly connected directly to the main girder web without passing through the floor support bracket, the steel deck can be designed with a reasonable transverse rib cross section. As a result, the structural weight can be reduced as compared with the case where the floor slab support bracket is used as in the related art.
Further, since the main girder and the steel slab are connected by a shear force transmitting member that transmits shear force in the bridge axis direction, the shear force in the bridge axis direction between the main girder and the steel slab is reliably ensured. The structure can be transmitted, and the steel slab and the main girder can be reliably combined.

In the bridge structure of the present invention, the covering concrete on the upper part of the remaining reinforced concrete may be removed.
Further, in the floor slab replacement method of the present invention, in the reinforced concrete floor slab removing step, the upper covering concrete of the remaining reinforced concrete may be removed.

  According to such a bridge structure and floor slab replacement method, it is only necessary to remove the upper covering concrete of the remaining reinforced concrete, so there is no need to remove the concrete between the studs erected on the main girder upper flange. . Since the concrete between the studs is very time-consuming to remove, by leaving the concrete, the time and effort for the removal operation can be greatly reduced. The reason for removing the covering concrete on the upper portion is to secure a space for adjusting the road surface height and to facilitate removal of the asphalt portion existing on the steel deck.

Further, in the bridge structure of the present invention, a height adjusting bolt capable of adjusting the height of the steel slab may be screwed into the steel slab so as to be able to abut the remaining reinforced concrete.
Further, in the floor slab replacement method of the present invention, a height adjusting bolt capable of adjusting the height of the steel slab is screwed into the steel slab so as to abut against the remaining concrete, and the steel slab is provided. After the disposing step, the height of the steel deck may be adjusted by turning the height adjusting bolt.

  According to such a bridge structure and floor slab replacement method, the height of the steel slab can be adjusted by turning the height adjustment bolt. Can be equal to the height of previous reinforced concrete slabs. That is, the road surface plan height can be adjusted at the site.

In the bridge structure of the present invention, an irregular-shaped material may be filled between the steel deck, the main girder upper flange, and the remaining reinforced concrete.
Furthermore, in the floor slab replacement method of the present invention, after the steel slab arranging step, an irregular-shaped material may be filled between the steel slab, the main girder upper flange, and the remaining reinforced concrete.
The filling of the irregular-shaped material may be performed before or after the steel slab connecting step, as long as it is after the steel slab arranging step.

According to such a bridge structure and a method of replacing a floor slab, the irregular-shaped material is filled between the steel slab, the main girder upper flange, and the remaining reinforced concrete. Corrosion of the exposed lower surface of the steel deck, the upper surface of the main girder upper flange, and the like can be prevented.
It is not necessary to obtain a large strength for the amorphous material. In the first place, the remaining reinforced concrete part was also cast in the era when there was not enough construction technology, and because it was shared for a long time, it was difficult to guarantee the strength enough to enable reliable design. For this reason, it is not necessary to require a large strength for the amorphous material to be filled therein.

Further, in the bridge structure of the present invention, a pavement portion is preliminarily constructed on the steel slab provided in the removing section, and the steel slab is adjacent to the steel slab, and the steel slab is adjacent to the steel slab. A temporary fixing plate is bridged between the reinforced concrete slabs that have not been replaced, and the temporary pavement portion is substantially flush with the pavement portion and the pavement portion on the reinforced concrete slab on the upper surface side of the temporary fixing plate. It may be constructed.
Further, in the floor slab replacement method of the present invention, a pavement portion is previously constructed on the steel slab provided in the removing section, and after the steel slab laying step, the steel slab and the steel slab are provided. A temporary fixing plate is bridged between the steel slab and the reinforced concrete slab, and a temporary pavement portion is substantially flush with the pavement portion and the pavement portion on the reinforced concrete slab on the upper surface side of the temporary slab. May be applied to

  According to such a bridge structure and a method of replacing a slab, the temporary pavement portion is constructed on the upper surface side of the temporary fixing plate so as to be substantially flush with the pavement portion of the steel slab and the pavement portion of the existing reinforced concrete slab. Therefore, the pavement of the existing reinforced concrete slab and the pavement of the updated (replaced) steel slab can be connected. For this reason, the lane regulation that was performed when the floor slab was replaced can be released, and the vehicle can be driven temporarily.

In the bridge structure of the present invention, a lateral rib mounting member may be bolted to the main girder web, and an end of the lateral rib may be bolted to the lateral rib mounting member.
Further, in the floor slab replacement method of the present invention, a horizontal rib mounting member is bolted to the main girder web, and after the steel floor slab laying step, the horizontal rib is bolted to the horizontal rib mounting member. May be.

  According to such a bridge structure and floor slab replacement method, the ends of the transverse ribs are bolted to the transverse rib mounting members bolted to the main girder web. Rigidly and easily connected to the main girder web closest to

In the bridge structure of the present invention, the length of the main girder web between the main girder upper flange and the horizontal rib mounting member in the vertical direction may be 224 mm or more.
Further, in the floor slab replacement method of the present invention, the length of the main girder web in the vertical direction between the main girder upper flange and the horizontal rib mounting member may be 224 mm or more.

  According to such a bridge structure and floor slab replacement method, it is possible to reduce the stress range in the portion of the main girder web that is joined to the main girder upper flange, and improve the fatigue resistance of the main girder.

Further, in the bridge structure of the present invention, the lateral rib mounting member and the end of the lateral rib are sandwiched by a splice plate and fastened by a high-strength bolt, so that the high-strength bolt is friction-joined to form the splice. A friction surface treatment by metal spraying may be applied to a joint surface of the plate around the bolt hole through which the high-strength bolt is inserted.
Further, in the floor slab replacement method of the present invention, when the horizontal rib is bolted to the horizontal rib mounting member, the horizontal rib mounting member and the end of the horizontal rib are sandwiched by a splice plate, and a high-strength bolt is used. The high-strength bolt may be friction-joined by tightening, and a joint surface around the bolt hole of the splice plate around which the high-strength bolt is inserted may be subjected to a friction surface treatment by metal spraying in advance.

  According to such a bridge structure and floor slab replacement method, a friction surface treatment by metal spraying is applied to a joint surface around a bolt hole of a splice plate to secure a friction coefficient necessary for high-strength bolt friction joint. Therefore, the number of high-strength bolts can be minimized.

In the bridge structure of the present invention, a plurality of the lateral rib attachment members may be provided.
Further, in the floor slab replacement method of the present invention, the plurality of lateral rib mounting members are bolted to the main girder web, and after the steel slab laying step, the lateral rib mounting members are attached to the plurality of horizontal rib mounting members. May be bolted together.

  According to such a bridge structure and floor slab replacement method, since a plurality of transverse rib attachment members can be configured to have predetermined bending strength and shear strength, the mass per one of the plurality of transverse rib attachment members can be increased. Can be lightened. Thereby, the worker can easily carry each lateral rib attachment member by human power.

Further, in the bridge structure of the present invention, the horizontal rib mounting member includes a first horizontal rib mounting member, and a second horizontal rib mounting member disposed below the first horizontal rib mounting member, A first splice plate joining the lateral ribs and the first lateral rib attaching member to each other; a second splice plate joining the lateral ribs, the first lateral rib attaching member and the second lateral rib attaching member to each other; May be provided.
Further, in the floor slab replacement method of the present invention, the first girder web has a first horizontal rib mounting member as the horizontal rib mounting member, and a second horizontal rib disposed below the first horizontal rib mounting member. The mounting member is bolted together, and in the horizontal rib rigid connection step, the horizontal rib and the first horizontal rib mounting member are joined to each other by a first splice plate, and the horizontal rib and the first horizontal rib are connected to each other by a second splice plate. The horizontal rib mounting member and the second horizontal rib mounting member may be joined to each other.

  According to such a bridge structure and floor slab replacement method, since the second splice plate joins not only the second lateral rib mounting member but also the first lateral rib attaching member, the first splice plate and the second splice plate in the lateral rib are connected. Concentration of stress on a portion located between the splice plate and the splice plate can be avoided.

In the bridge structure of the present invention, the lateral rib attaching member includes a first lateral rib attaching member, and a second lateral rear attaching member disposed below the first lateral rib attaching member, A first splice plate joining the lateral ribs, the first lateral rib attaching member and the second lateral rib attaching member to each other, a second splice plate joining the lateral ribs and the second lateral rib attaching member to each other, May be provided.
Further, in the floor slab replacement method of the present invention, the first girder web has a first horizontal rib mounting member as the horizontal rib mounting member, and a second horizontal rib disposed below the first horizontal rib mounting member. The mounting member is bolted, and in the horizontal rib rigid connection step, the horizontal rib, the first horizontal rib mounting member, and the second horizontal rib mounting member are joined to each other by a first splice plate, and the second splice plate is connected to the horizontal rib. The lateral rib and the second lateral rib mounting member may be joined to each other.

  According to such a bridge structure and floor slab replacement method, not only the first lateral rib mounting member but also the second lateral rib mounting member is joined by the first splice plate. Concentration of stress on a portion located between the splice plate and the splice plate can be avoided.

Further, in the bridge structure of the present invention, the shear force transmitting member includes a first piece fixed to the main girder web by a first fixing member, and a rib joined to a lower surface of the deck plate. It may include a second piece fixed by a second fixing member disposed at a position equivalent to the one fixing member in the vertical direction, and a connecting piece connected to the first piece and the second piece, respectively.
Further, in the method of replacing a slab of the present invention, in the steel slab joining step, a first piece of the shear force transmitting member is fixed to the main girder web by a first fixing member, and is attached to a lower surface of the deck plate. The second piece of the shear force transmitting member is fixed to the attached rib by a second fixing member arranged at a position equivalent to the first fixing member in the vertical direction, and the connecting piece of the shear force transmitting member is , May be connected to the first piece and the second piece, respectively.

  According to such a bridge structure and floor slab replacement method, the position where the first piece is fixed to the main girder web by the first fixing member, and the position where the second piece is fixed to the rib by the second fixing member. , Are the same in the vertical direction, so that the generation of a moment about the axis along the horizontal plane on the shear force transmitting member is suppressed. Therefore, it is less necessary for the shear force transmitting member to withstand the moment, and the weight of the shear force transmitting member can be reduced.

  According to the present invention, the horizontal ribs of the steel deck can be easily and firmly connected to the web of the main girder, the rigidity as a bridge can be secured, and further, the bridge between the main girder and the steel deck can be moved in the bridge axis direction. Shear force can be transmitted reliably.

It is an operation | movement flowchart of the floor slab replacement method of the bridge which concerns on the 1st Embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view for explaining a method of replacing a floor slab of a bridge according to a first embodiment of the present invention, as viewed obliquely from above a bridge before floor slab replacement. However, only one lane is shown. FIG. 3 is a perspective view of the bridge before the floor slab replacement as viewed obliquely from below. FIG. 3A is a perspective view of the bridge viewed from diagonally below, and FIG. 4B is a cross-sectional view including a horizontal rib mounting member of the right main girder, showing a state where the horizontal rib mounting member is mounted on the main girder web. It is. FIG. 2A is a perspective view of the lateral rib attaching member, and FIG. 2B is a perspective view of the lateral rib attaching member, as viewed from the direction indicated by the arrow A in FIG. It is sectional drawing of the principal part which shows the state which attached the horizontal rib attachment member to the main girder web. FIG. 3 is a perspective view showing a state where a part of the reinforced concrete floor slab has been removed, and the bridge is viewed from obliquely above. FIG. 2 is a perspective view showing a state in which a part of the reinforced concrete floor slab has been removed, as viewed obliquely from below the bridge. It is sectional drawing which shows the state from which the upper part of the remaining concrete was removed. FIG. 3A shows a state where a steel slab is installed. FIG. 5A is a perspective view of the bridge viewed from obliquely above, and FIG. 5B is a perspective view of the bridge showing a state where a temporary fixing plate is installed. It is. FIG. 3A shows a state in which a steel slab is installed. FIG. 4A is a perspective view of the bridge viewed from obliquely below, and FIG. 4B is a front view of the bridge. FIG. 3A is a cross-sectional view illustrating a main part including residual concrete, and FIG. 4B is a cross-sectional view illustrating a state where an amorphous material is filled. FIG. 3A shows a state in which the lateral ribs are rigidly connected to the main girder web, in which FIG. 3A is a perspective view as viewed obliquely from below, and FIG. It is a perspective view of the principal part in FIG.10 (b). FIG. 13 is a plan sectional view of a main part in FIG. FIG. 4A shows a shear force transmitting member, wherein FIG. 4A is a cross-sectional view of a main part showing a state where the shear force transmitting member is attached, FIG. 4B is a perspective view of the shear force transmitting member, and FIG. FIG. 4D is a front view of the member, FIG. 4D is a side view of the shear force transmitting member, and FIG. 5E is a bottom view of the shear force transmitting member. (A) is a sectional view of a main part showing a steel slab and a reinforced concrete slab adjacent to the slab, and (b) is a temporary pavement in which a temporary fixing plate is temporarily provided between the steel slab and the reinforced concrete slab. It is sectional drawing of the principal part which shows the state which performed. It is a sectional view showing an important section of a bridge structure concerning a 1st embodiment of the present invention. It is a perspective view seen from diagonally above showing a state where a removal part was provided in order to explain a method of installing the next steel deck in the first embodiment of the present invention. It is the perspective view which looked at the state where the removal part was provided and which was seen from diagonally below. It is the perspective view seen from slanting upper part which shows the state where the same steel deck was installed. FIG. 2 is a perspective view showing a state in which a part of a reinforced concrete floor slab in the other lane is removed, and the bridge is viewed obliquely from above. FIG. 4 is a front sectional view of a removed portion, showing a state in which a part of the reinforced concrete slab of the other lane is removed. FIG. 2 is a perspective view showing a state in which a steel deck is installed on the other lane side, as viewed obliquely from above. FIG. 3 is a front sectional view of the steel slab, showing a state where a steel slab is installed on the other lane side. FIG. 4 is a front sectional view showing a state in which a temporary fixing plate is temporarily provided between a steel slab and a reinforced concrete slab, and temporary paving is performed. It is a front sectional view showing the state where the steel deck adjacent to a bridge axis direction was joined by the same panel joint. It is a front sectional view showing the state where the steel slab adjacent to the bridge axis orthogonal direction was joined by the same panel joint. It is the perspective view seen from the slanting lower part which shows the state where the next steel deck was installed. FIG. 9 is a perspective view for explaining a method of replacing a floor slab of a bridge according to a second embodiment of the present invention, and is a perspective view of a bridge before floor slab replacement as viewed obliquely from above. However, only one lane is shown. FIG. 3 is a perspective view of the bridge before the floor slab replacement as viewed obliquely from below. FIG. 3 is a perspective view showing a state where a part of the reinforced concrete floor slab has been removed, and the bridge is viewed from obliquely above. FIG. 2 is a perspective view showing a state in which a part of the reinforced concrete floor slab has been removed, as viewed obliquely from below the bridge. FIG. 2 is a perspective view showing a state where a steel slab is installed, as seen from obliquely above the bridge. FIG. 3 is a perspective view showing a state in which a steel slab is installed, which is a perspective view of a bridge viewed obliquely from below. FIG. 4 is a perspective view showing a state in which a further part of the reinforced concrete floor slab has been removed, as viewed obliquely from above the bridge. FIG. 3 is a perspective view showing a state in which a further part of the reinforced concrete floor slab has been removed, as viewed from diagonally below the bridge. FIG. 3 is a perspective view showing a state where the next steel slab is installed, when the bridge is viewed obliquely from above. FIG. 3 is a perspective view showing a state where the next steel slab is installed, and is a view of a bridge viewed from obliquely below. It is sectional drawing which shows the principal part of the floor slab replacement structure of the same. It is a sectional view showing an important section of a bridge concerning a 3rd embodiment of the present invention. It is the perspective view which looked at the principal part of the bridge from diagonally downward. It is the perspective view which looked at the 1st and 2nd horizontal rib attachment member of the same bridge from diagonally downward. It is sectional drawing which shows the principal part containing the remaining concrete of a bridge. It is a figure which shows the analytical model of the bridge when the length of the main girder web between a main girder upper flange and a 1st horizontal rib attachment member is comparatively long. It is a figure which shows the analytical model of a bridge when the length of the main girder web between a main girder upper flange and a 1st horizontal rib attachment member is comparatively short. It is a sectional view showing an important section of a bridge concerning a modification of a 3rd embodiment of the present invention.

Hereinafter, embodiments of a bridge structure and a floor slab replacement method according to the present invention will be described with reference to the drawings.
(First Embodiment)
In the present embodiment, a case where a part of a reinforced concrete slab supported and laid on a main girder of a bridge is replaced with a steel slab will be sequentially described according to the replacement construction steps.

In the first embodiment, FIG. 1 shows a case in which a main girder adjacent in the bridge width direction has an interval of about 3 m, and a part of the reinforced concrete slab is cut in the bridge width direction to be replaced with a new steel slab. This will be described with reference to the work flowchart shown in FIG.
2A and 2B show the bridge before the floor slab replacement (however, only one lane (two lanes on one side in the case shown in the figure)), FIG. 2A is a perspective view seen from obliquely above, and FIG. It is the perspective view seen from diagonally downward.
As shown in FIGS. 2A and 2B, the bridge (bridge structure) 10 includes a main girder 11, a cross girder 12, an inclined structure 13, and a reinforced concrete floor slab 14.
The main girder 11 is formed of an H-beam or an I-beam, and is provided so as to extend in the bridge axis direction (the Z direction in FIG. 2A). In the case shown in the figure, of the six main girders provided in total in both lanes, only three of the lanes on one side are shown. These main girders 11 are arranged at predetermined intervals in the bridge width direction (horizontal direction orthogonal to the bridge axis direction (so-called bridge axis orthogonal direction; X direction in FIG. 2A)). The main girder 11 has a main girder web 11a, a main girder upper flange 11b, and a main girder lower flange 11c. The main girder 11 is provided between abutments and piers (not shown).

  The cross beam 12 is formed of an H-beam or an I-beam, extends in the bridge width direction, is bridged between adjacent main beams 11, 11, and the end of the cross beam 12 is welded to the main beam web 11a. They are connected by bolts or the like. Further, a plurality of cross beams 12 are arranged at predetermined intervals in the bridge axis direction. However, since a part of the bridge 10 is shown in FIG. 2B, two horizontal beams 12 coaxially extend in a direction orthogonal to the bridge axis. A digit 12 is provided.

  The anti-tilt structure 13 is for resisting a horizontal load such as a wind or an earthquake, and has a truss structure including an upper chord material, a lower chord material, a vertical material, a diagonal material and the like. The inclined structure is installed between the adjacent main girders 11 and 11 and connected to the main girders 11 by gussets or the like. In addition, a plurality of the tilt structures 13 are arranged at predetermined intervals in the bridge axis direction, but FIG. 2B shows a part of the bridge 10, so that two tilt structures extending coaxially in the bridge axis orthogonal direction. 13 are provided, and the tilt structure 13 is provided at a position separated in the bridge axis direction and sandwiching the cross beam 12.

  Reinforced concrete floor slab 14 has reinforcing bars arranged vertically and horizontally inside, and on the lower surface of the reinforced concrete floor slab 14, a ridge (haunch portion) 14a projecting from the lower surface extends in the bridge axis direction, In the present embodiment, three ridges 14a are formed at predetermined intervals in the bridge width direction. The three ridges 14a are located immediately above the three main girders 11, and are fixedly installed on the main girder upper flange 11b. A plurality of studs (not shown) are provided on the upper surface of the main girder upper flange 11b at predetermined intervals in the bridge width direction and the bridge axis direction, respectively, and these studs are connected to the concrete of the reinforced concrete floor slab 14. Further, the reinforced concrete floor slab 14 is provided with ground covers 14b at both ends in the bridge width direction, and a row 14c at one end. Further, on the upper surface of the reinforced concrete floor slab 14, a pavement portion 15 made of asphalt or the like is provided between the ground coverings 14b.

When a part of the reinforced concrete slab 14 supported and laid on the main girder 11 of the bridge 10 having such a configuration is to be replaced with a new steel slab, the bridge 10 is first prepared as a preparation step (step S1 in FIG. 1). Below, a not-shown full-length suspension scaffold is installed, and from this full-length suspension scaffold, members that interfere with the installation (replacement) of a new steel slab are removed, improved, and finished (partly grinder work). When the entire scaffold is installed in advance for inspection or the like, the same work can be performed using the scaffold.
Next, as shown in FIG. 3, the horizontal rib mounting member 16 is bolted to the upper part of the main girder web 11a by a high strength bolt. In this case, work is performed on the lower surface side of the reinforced concrete floor slab 14, and the lateral rib mounting member 16 is bolted to the main girder web 11a (step S2 in FIG. 1).
FIG. 3B is a cross-sectional view of the right main girder 11 in FIG. 3A including the horizontal rib mounting member 16. In addition, the right side referred to below means the right side as viewed from the display surface in this specification. The same applies to the left side.
As shown in FIG. 4, the horizontal rib mounting member 16 is formed in a T-shaped cross section, and has a rectangular plate-shaped fixing plate 16a and a central portion in the width direction of the fixing plate 16a, which is perpendicular to the plate surface of the fixing plate 16a. And a connection plate 16b of a rectangular plate shape protruding in the direction. The fixed plate 16a and the connecting plate 16b have the same vertical length, and the length of the connecting plate 16b protruding from the fixed plate 16a is determined by the connecting plate 16b Is set to a length such that the front end surface can contact. The horizontal rib mounting member 16 is a member for making the horizontal rib 33 and the main girder web 11a continuous, and is attached to the main girder web 11a by tension bolt bonding. They are connected by two-sided shear friction welding.
The fixing plate 16a has a plurality of bolt holes 16c, and the connecting plate 16b has a plurality of bolt holes 16d.

  Such a horizontal rib mounting member 16 is mounted by affixing a fixing plate 16a to a web surface of a main girder web 11a located below a portion where a new steel slab is to be replaced and by bolting. In this embodiment, a part of the reinforced concrete slab 14 is replaced with a steel slab between the right main girder 11 and the central main girder 11 in FIG. On both web surfaces of the main girder web 11a of the right main girder 11, a horizontal rib mounting member 16 is attached substantially symmetrically with respect to a center portion in the thickness direction of the main girder web 11a. The horizontal rib mounting member 16 is mounted on the web surface of the main girder web 11a facing the right main girder 11 side. In FIG. 5, the right lateral rib mounting member 16 has a longer vertical direction than the left lateral rib mounting member 16, and the lower end of the right lateral rib mounting member 16 has a left lateral rib mounting member. 16 protrudes downward from the lower end. This is because the vertical length of the end of the horizontal rib 33A on the main girder web 11a side is longer than the vertical length of the end of the horizontal rib 33B on the main girder web 11a side, and the horizontal rib 33A Is protruded downward from the lower end of the lateral rib 33B (see FIG. 10B). Accordingly, when the vertical length of the end of the horizontal rib 33A on the main girder web 11a side is equal to the vertical length of the end of the horizontal rib 33B on the main girder web 11a side, the right horizontal rib mounting member 16 is provided. May be equal to the vertical length of the left lateral rib mounting member 16.

When the horizontal rib mounting member 16 is connected to the web surface of the right main girder web 11a, the web surface is peeled off, and then connected by ordinary friction welding using high-strength bolts. That is, as shown in FIG. 5, the main girder web 11a is provided with a bolt hole 11d at a position corresponding to the bolt hole 16c, and the bolt hole 11d is in contact with both web surfaces of the main girder web 11a. The high-strength bolts 18 are inserted into the bolt holes 16c, 16c of the fixing plate 16a of the lateral rib mounting members 16, 16 and the nuts 18a are screwed into the high-strength bolts 18 to fasten the web of the main girder web 11a. The lateral rib mounting member 16 is connected to the surface.
At this time, the fixing plate 16a of the horizontal rib mounting member 16 is pre-drilled at the factory and the bolt hole 16c is provided, while the main girder web 11a is in a stage before the joining operation is performed. No bolt hole 11d is provided. The lateral rib mounting member 16 is temporarily installed at an appropriate position, and a hole is formed in the main girder web 11a using a tool such as a portable drilling machine (not shown) on the site using the bolt hole 16c as a template. At the time of joining work, there is a possibility that a positional shift may occur between the members, and it is necessary to adjust the position of the bolt hole. Position adjustment becomes possible.
The same applies to the case where the horizontal rib mounting member 16 is connected to the web surface of the main girder web 11a at the center.
A reinforced concrete floor slab supported and laid by the center main girder 11 and the left main girder 11 is provided on the web surface on the opposite side (left main girder 11 side) of the center main girder web 11a. When replacing a part of 14 with a new steel slab, the horizontal rib mounting member 16 is mounted in the same manner.
After attaching the horizontal rib attaching member 16 to the main girder 11, as shown in FIG. 6, lane regulation of upper traffic is performed as necessary (step S3 in FIG. 1). When performing lane regulation, temporary guards 17 are erected at predetermined intervals in the bridge axis direction at the center of the road surface in the width direction (bridge width direction). FIG. 6 shows a case in which one lane on the right side is restricted. The left side of the temporary guard 17 is a vehicle lane, and the right side is a construction zone.

  Next, in the construction zone, by removing a part of the reinforced concrete floor slab 14 other than a part provided on the upper surface side of the main girder upper flange 11b within a predetermined width in the bridge axis direction (Z direction). The removal section 20 is provided in a part of the reinforced concrete slab 14, and the reinforced concrete 21 is left on the upper surface side of the main girder upper flange 11b in the removal section 20 (a reinforced concrete slab removal step).

That is, as shown in FIGS. 6 and 7, a predetermined portion in the bridge axis direction of the reinforced concrete floor slab 14 located between the main girder 11 located on the right side in the bridge width direction and the main girder 11 located in the center portion. According to the plan view shape and size (in this embodiment, substantially rectangular shape in plan view) of a steel floor slab described later, the steel slab is cut and removed by a concrete cutter (step S4 in FIG. 1). At this time, by removing a portion other than the portion provided on the upper surface side of the main girder upper flange 11b to form a space, the removal portion 20 is provided at a predetermined portion (part) of the reinforced concrete floor slab 14. In this case, the reinforced concrete 21 is left on the entire upper surface of the main girder upper flange 11b of the right main girder 11, and is left on almost half of the upper surface of the main girder upper flange 11b of the center main girder 11 (half in the bridge width direction). The reinforced concrete 21 is left.
At this time, in the peripheral portion surrounding the removing portion 20 of the reinforced concrete floor slab 14, the portion of the reinforced concrete floor slab 14 adjacent to the removing portion 20 in the bridge width direction is the upper side of the main girder upper flange 11 b of the main girder 11. In, a part of the pavement portion 15 is removed along the bridge axis direction, and an edge along the removal portion 20 is exposed. Further, for the portion of the reinforced concrete slab 14 located between the main girders 11 and 11 and adjacent to the removing portion 20 in the bridge axis direction, the pavement portion 15 is removed along the bridge width direction, and Expose the edge of

  The length in the bridge axis direction of the rectangular removing portion 20 formed by cutting a predetermined portion of the reinforced concrete floor slab 14 into a substantially rectangular shape in a plan view in this manner is the new steel slab to be replaced. Is slightly longer than the length in the bridge axis direction in plan view. Further, when a predetermined portion of the reinforced concrete floor slab 14 is cut into a substantially rectangular shape in plan view, the cut is made including the right ground cover 14b and the high rail 14c, so that the outer side (right side) of the removing unit 20 in the bridge width direction is opened. I have.

  In this reinforced concrete floor slab removing step, as shown in FIG. 8, the covering concrete 22 on the upper part of the remaining reinforced concrete 21 on the main girder upper flange 11b of the right main girder 11 and the pavement 15 on the upper part are hammered. It is removed by a manual operation such as a blow (step S5 in FIG. 1). In this case, the covering concrete 22 above the upper reinforcing bar 21a of the remaining reinforced concrete 21 is removed, but steel materials such as studs (not shown) and slab anchors (not shown) standing on the upper surface of the main girder upper flange 11b are left. I do.

Next, as shown in FIG. 9A, a new steel slab 30 is disposed on the removing section 20 so as to cover the remaining reinforced concrete 21 and temporarily placed (steel slab arranging step). . In this case, the remaining reinforced concrete 21 is disposed so as to be sandwiched in the bridge width direction between lower extension vertical ribs 32A, 32A to be described later, and the lower surface of the deck plate 31 is brought into contact with the upper surface of the remaining reinforced concrete 21 to thereby increase the steel floor. The plate 30 is temporarily placed (step S6 in FIG. 1).
As shown in FIG. 10, the steel slab 30 includes a deck plate 31, a plurality of vertical ribs 32 joined to the lower surface of the deck plate 31 by welding or the like, and horizontal ribs arranged at right angles to the vertical ribs 32. 33, and a pavement portion 34 is pre-installed on the upper surface of the deck plate 31. The outer peripheral edge 31 a of the deck plate 31 projects outward from the outer peripheral edge of the pavement portion 34.

The plurality of vertical ribs 32 extend in the bridge axis direction, and are provided in parallel at predetermined intervals in the bridge width direction. As shown in FIG. 10B, FIG. 11, and FIG. 17, two of the plurality of vertical ribs 32 arranged so as to sandwich the main girder upper flange 11b in the bridge width direction are other vertical ribs. 32, and the lower end extends sufficiently below the lower surface of the main girder upper flange 11b in a state where the lower surface of the deck plate 31 of the newly installed steel slab 30 is in contact with the upper surface of the remaining reinforced concrete 21. Outgoing lower ribs 32A are provided. The downwardly extending vertical ribs 32A, 32A mechanically act as vertical ribs of the steel slab 30 and, as a part of the web of the main girder 11, communicate with the steel slab 30 through the shear force transmitting member 50. It has the function of transmitting the shear force in the bridge axis direction between the main girders 11. Further, as other functions, it functions as a part of a formwork that covers the periphery of the remaining reinforced concrete 21 and fills an irregular material 47 described later between the steel slab 30 and the steel slab 30.
When the newly installed steel slab 30 is disposed on the rectangular removal portion 20 so as to cover the remaining reinforced concrete 21, the lower extending vertical ribs 32 </ b> A, 32 </ b> A are the main girder upper flanges of the right main girder 11. 11b is arranged so as to sandwich it in the bridge width direction. At this time, there is a gap between the end of the main girder upper flange 11b in the bridge width direction and the surface of the lower extending longitudinal ribs 32A, 32A facing the end in the bridge width direction. The sealing material 36 is fitted into the gap. Also, from the surface of the lower extending vertical ribs 32A, 32A facing the main girder upper flange 11b to the lower surface of the sealing material 36 and the lower surface of the main girder upper flange 11b, a concrete formwork, a titanium foil for waterproofing and corrosion prevention. 37 is pasted.

As shown in FIG. 11A, a height adjusting bolt 40 capable of adjusting the height of the steel slab 30 is screwed to the steel slab 30 so as to be able to abut the remaining reinforced concrete 21. . That is, a screw hole 41 is provided in a portion of the deck plate 31 located above the remaining reinforced concrete 21 on the main girder upper flange 11 b of the right main girder 11, and a height adjusting bolt 40 is provided in the screw hole 41. Are screwed, and the tip (lower end) of the height adjustment bolt 40 is in contact with the upper surface of the remaining reinforced concrete 21. A plurality of such height adjustment bolts 40 are provided at the edge of the deck plate 31 in the bridge axis direction and above the main girder 11.
Then, after the steel slab arranging step, the height of the steel slab 30 is adjusted by turning the height adjusting bolts 40 in the forward and reverse directions as appropriate to raise and lower the steel slab 30. That is, the height of the steel slab 30 is adjusted so that the upper surface of the pavement portion 34 of the steel slab 30 is substantially flush with the upper surface of the pavement portion 15 of the reinforced concrete slab 14 (step S7 in FIG. 1). ).

Next, the lateral ribs 33 of the steel deck 30 are rigidly connected to the main girder web 11a closest to the ends at the ends of the lateral ribs 33 in the bridge width direction (transverse rib rigid connection step) (FIG. 1). Step S8).
As shown in FIG. 10, the steel deck slab 30 is disposed on the lower surface side of the deck plate 31 in the bridge width direction, and at least a part of one end face or both end faces in the bridge width direction is the closest to the main girder 11. It has a horizontal rib 33 facing the web surface of the main girder web 11a.
Specifically, two horizontal ribs 33 (33A, 33B) extending in the bridge width direction are joined to the lower surface of the deck plate 31 by welding or the like with the right main girder 11 therebetween.

  As shown in FIG. 12, the horizontal rib 33 </ b> A on the right side in the bridge width direction of the steel slab 30 of the present embodiment has a lower end formed in a substantially horizontal direction up to a certain distance from the main girder 11. At a position distant from the main girder 11, the lower end is formed in a plate-like shape that is inclined so as to gradually approach the deck plate 31 side as the distance from the main girder 11 increases. A part of one end surface 33a of the lateral rib 33A in the bridge width direction (that is, the end surface on the main girder side) is opposed to the right web surface of the nearest (right) main girder web 11a. A flange 33b is fixed to the lower end surface of the horizontal rib 33A that is inclined (inclined with respect to the horizontal plane). Such a horizontal rib 33A is disposed at a substantially central portion in the length direction (bridge axis direction) of the short side of the deck plate 31, and the vertical rib 32 is disposed orthogonal to the horizontal rib 33A. The intersection is welded. The lower extending vertical rib 32A has a surface opposite to the main girder upper flange 11b facing one end surface 33a of the horizontal rib 33A, and the extending direction of the lower extending vertical rib 32A and the horizontal rib 33A. Is abutted on one end surface 33a of the lateral rib 33A so that the extending direction is orthogonal to the extension direction of the lateral rib 33A, and is joined to the lateral rib 33A by welding. Further, a part of the lower side of the one end surface 33a of the lower extending vertical rib 32A extends below the lower surface of the main girder upper flange 11b, and the nearest surface of the main girder 11 is the main girder web 11a. It is in a state of facing the web surface.

  As shown in FIG. 10 (b), FIG. 13 and FIG. 17, the lateral ribs 33B on the left side in the bridge width direction of the steel slab 30 are provided at the base formed in a rectangular plate shape and at both ends in the bridge width direction. It is formed in a plate shape integrally provided with a protruding portion 33c that is provided and protrudes downward from the base. The protruding portion 33c is formed in a plate shape whose lower end gradually protrudes downward as it goes to both ends in the extending direction of the horizontal rib 33B. Therefore, both ends of the horizontal rib 33B and the vicinity thereof are shaped such that the length in the vertical direction increases toward both ends in the extending direction due to the protruding portions 33c. Further, both end surfaces of the horizontal rib 33B face the web surface of the nearest main girder web 11a, respectively. In other words, a substantially lower half of one end face (left end face) 33d of the horizontal rib 33B faces the web face of the main girder web 11a of the main girder 11 at the central portion, and the other end face (right end face) 33d of the horizontal rib 33B. A substantially lower half faces the web surface of the main girder web 11a of the right main girder 11. Such a horizontal rib 33B is disposed at a substantially central portion in the length direction of the short side of the deck plate 31, that is, disposed on an extension of the horizontal rib 33A, and the vertical rib 32 is disposed orthogonal to the horizontal rib 33B. And their intersections are welded.

The bridge ribs 33A, 33B are arranged such that one end face of each of the transverse ribs 33A, 33B in the bridge width direction is opposed to the web surface of the main girder web 11a. Direction ends 33e, 33e are rigidly connected to the nearest main girder webs 11a, 11a. Thus, it is possible to reduce the stress generated due to the traffic load accompanying the slab action of the steel slab 30. That is, even with the horizontal ribs 33 having the same height, the stress generated in the steel slab 30 by being rigidly connected to the main girder webs 11a, 11a is reduced, and the fatigue life can be sufficiently ensured.
Specifically, in the present embodiment, as shown in FIG. 14, the lateral rib 33B is in a state where one end surface 33d of the end 33e in the bridge width direction is opposed to the web surface of the main girder web 11a. After the end 33e and the connecting plate 16b are spliced from both sides thereof, the end of the connecting plate 16b is brought into contact with the leading end surface of the connecting plate 16b of the horizontal rib mounting member 16 fixed to the main girder web 11a of the main girder 11 at the center. The high-strength bolts 45 and the nuts 45a frictionally join the plates 42 and 42. Thereby, the lateral rib 33B is rigidly connected to the main girder web 11a closest to the end 33e at the left end 33e in the bridge width direction of the lateral rib 33B. With such a structure, as described later, it is possible to easily adjust the irregularity of the vertical position of the entire steel slab (particularly the deck plate) on site. In the case of the structure of Patent Document 1, a horizontal rib is placed on the bracket, but in this configuration, when adjusting the position in the upward direction, a spacer is required between the bracket and the horizontal rib. The adjustment work is troublesome, and the fine adjustment is extremely difficult. On the contrary, it is impossible to make the adjustment downward.
Similarly, a splice plate is attached to the right end 33e of the lateral rib 33B in the bridge width direction at the distal end of the connecting plate 16b of the lateral rib mounting member 16 fixed to the main girder web 11a of the right main girder 11. 42, 42 and the high strength bolt 45 and the nut 45a are rigidly connected.

  As shown in FIG. 4, a plurality of bolt holes 16d are previously formed in the connection plate 16b in a factory or the like, and a plurality of bolt holes 16d are previously formed in the splice plate 42 in the factory or the like as shown in FIGS. 42c is formed. Then, using the bolt holes 42c of the splice plate 42 as a template, holes are drilled by using a tool such as a portable drilling machine (not shown), and bolt holes 33g are formed at the ends 33e of the lateral ribs 33B in the bridge width direction. I do. Alternatively, a bolt hole 33g can be formed at the end 33e in the bridge width direction of the lateral rib 33B by a multiple drilling tool (not shown). That is, a plurality of bolt holes 42c formed in the splice plate 42 that is in contact with the surface of the end portion 33e in the bridge width direction of the lateral rib 33B have a number corresponding to the number of the bolt holes 42c. A bolt hole 33g is formed in the end 33e while inserting a drilling tool. As a result, the working time can be greatly reduced as compared with a single ordinary portable drilling machine. Further, at the time of the joining operation, there is a possibility that a positional shift may occur between the members, and the position of the bolt hole may have to be adjusted. However, by this method, the bolt hole between the splice plate 42 and the lateral rib 33B is formed. Relative position adjustment can be easily performed.

  Then, after inserting the high-strength bolts 45 into the bolt holes 42c, 16d, 42c and the bolt holes 42c, 33g, 42c, which are coaxially arranged, respectively, screw a nut 45a into the high-strength bolt 45 and tighten them. Thereby, the lateral rib 33B is rigidly connected to the nearest main girder web 11a by frictional joining at the end 33e in the bridge width direction of the lateral rib 33B. 12 and 13, the illustration of the high-strength bolt 45 is omitted.

  Further, in the friction joining structure using such high-strength bolts, the splice plate 42 to which the surface of the end 33e in the bridge width direction of the lateral rib 33B is joined and the splice plate 42 to which the surface of the connection plate 16b is joined. In order to stably secure a friction coefficient required for friction joining, a friction surface treatment using metal spraying of aluminum or the like is performed on a surface of the surface by a factory or the like. In this friction surface treatment, the surface of the splice plate 42 is ground-treated to such an extent that the sprayed metal is fixed, and then the low-strength metal aluminum is sprayed in a molten state to form an aluminum sprayed layer. ing. The underlayer treatment is, for example, blasted so that the surface roughness (maximum height Rz) is 50 μm or more.

The aluminum sprayed layer (metal sprayed layer) is formed in a circumference on the joint surface centered on the bolt hole 42c into which the high-strength bolt 45 is inserted. The diameter of this circumference is set to, for example, about three times the shaft diameter of the high-strength bolt 45. The thickness of the aluminum sprayed layer is set within a range of 200 μm or more and 500 μm or less, for example, 300 μm.
By providing the aluminum sprayed layer on the splice plate 42 in this manner, the friction coefficient required for friction joining can be secured, and the number of high-strength bolts 45 can be minimized.

Similarly, as shown in FIG. 12, for the lateral rib 33A, the right main girder in a state where the one end surface 33d of the one end 33e in the bridge width direction is opposed to the web surface of the main girder web 11a. After abutting on the distal end surface of the connecting plate 16b of the horizontal rib mounting member 16 fixed to the main girder web 11a of the eleventh, the end 33e and the connecting plate 16b are sandwiched between the splice plates 42, 42 from both sides thereof, By fastening with the high-strength bolt 45, the horizontal rib 33B is rigidly connected to the main girder web 11a at the end 33e of the horizontal rib 33A, which is closest to the end 33e.
Also in such a friction joining structure using high-strength bolts, the splice plate 42 to which the surface of the end 33e in the bridge width direction of the lateral rib 33A is joined and the splice plate 42 to which the surface of the connection plate 16b is joined. Has been subjected to a friction surface treatment by metal spraying of aluminum or the like at a factory or the like. Using the bolt holes 42c of the splice plate 42 as a template, holes are drilled using a not-shown portable drilling machine or a tool such as a multiple drilling tool, and ends of the lateral ribs 33A in the bridge width direction. The fact that a bolt hole 33g may be formed in 33e is the same as in the case of the connection between the splice plate 42 and the lateral rib 33B.

  Next, as shown in FIG. 11 (b), the irregular material 47 is filled between the steel deck 30, the main girder upper flange 11 b, and the remaining reinforced concrete 21. That is, after removing the height adjusting bolt 40 from the screw hole 41, the height adjusting bolt 40 is removed from the screw hole 41 into a space between the lower extension ribs 32A, 32A in which the main girder upper flange 11b and the remaining reinforced concrete 21 are accommodated. The irregular-shaped material 47 is filled (step S9 in FIG. 1). As described above, the lower extending vertical ribs 32A, 32A are disposed so as to sandwich the main girder upper flange 11b in the bridge width direction, and a gap between the main girder upper flange 11b and the lower extending vertical ribs 32A, 32A is provided. Since the seal material 36 is fitted, the irregular-shaped material 47 filled from the screw hole 41 is used for the deck plate 31 of the steel slab 30, the main girder upper flange 11b, the seal material 36, and the lower extending vertical rib. The space is surrounded by the spaces 32A and 32A without gaps and the space is filled. Thereby, corrosion of the upper reinforcing bar 21a of the remaining reinforced concrete 21, the lower surface of the deck plate 31, the upper surface of the main girder upper flange 11b, and the like can be prevented.

As the irregular-shaped material 47, for example, mortar is used, but other materials having rapid curability and fluidity such as non-shrinkable resin and rubber latex can also be used.
In addition, such a filling operation of the irregular-shaped material 47 may be performed after a steel slab joining step by the shear force transmitting member 50 described later. In addition, in order to improve the overall work efficiency, the steel slabs 30 for several panels may be filled together after construction. This is because the dead load and the live load (traffic load) acting on the steel slab 30 are transmitted to the main girder web 11a through the lateral ribs 33 in design.

Next, as shown in FIGS. 10, 12, and 15, the main girder 11 and the steel slab 30 are joined by a shear force transmitting member 50 that transmits a shear force in the bridge axis direction (steel slab joining step). (Step S10 in FIG. 1).
The shear force transmitting member 50 transmits the shear force in the bridge axis direction between the main girder 11 and the steel slab 30 mutually, and is formed by, for example, bending a steel plate made of a rectangular plate-shaped SBHS steel material, The first fixing plate 50a, the second fixing plate 50b, and the connecting plate 50c are integrally provided. Further, the first fixing plate 50a and the second fixing plate 50b are respectively provided with bolt holes 50d through which bolts 51 and 52 described later can be inserted, which are spaced apart in the bridge axis direction.
Note that the shear force transmitting member 50 may be formed of, for example, SUS or cast iron other than the SBHS steel material. Further, in the present embodiment, the shear force transmitting member 50 is formed in a crank shape (substantially Z shape in cross section), but the main girder 11 and the steel slab 30 can transmit the shear force in the bridge axis direction. As long as it can be combined, it may have another shape as required for design and construction. Since the role of the shear force transmitting member 50 is to transmit the shear force, it is sufficient that the necessary cross-sectional area can be ensured in design.

  The first fixed plate 50a and the second fixed plate 50b are formed in a rectangular plate shape that is long in the bridge axis direction, and the plate surfaces (surfaces) are spread in the vertical direction and the bridge axis direction. The first fixed plate 50a and the second fixed plate 50b have the same long side and short side, and are separated in parallel in the direction orthogonal to the bridge axis (bridge width direction). The lengths of the short sides of the first fixed plate 50a and the second fixed plate 50b may be different, but the lengths of the long sides are preferably equal.

The connection plate 50c connects the first fixed plate 50a and the second fixed plate 50b, and is formed in a rectangular plate shape that is long in the bridge axis direction, and the plate surface (surface) extends in the horizontal direction. ing. The length of the long side of the connection plate 50c is equal to the length of the long side of the first fixed plate 50a and the second fixed plate 50b, and one long side of the connection plate 50c is the first fixed plate 50a. And the other long side of the connecting plate 50c is connected to the upper long side of the second fixed plate 50b. The length of the short side of the connecting plate 50c is substantially equal to the horizontal distance between the edge of the main girder upper flange 11b in the width direction and the web surface of the main girder web 11a.
Note that the length of the shear force transmitting member 50 in the bridge axis direction is appropriately determined. If the total cross-sectional area of the shear resistance cross section of the shear force transmitting member 50 has the same cross-sectional area as that of the main girder web 11a, the exchange of the shearing force between the steel slab 30 and the main girder 11 is possible, and as a result, As a result, it is possible to synthesize the steel slab 30 and the main girder 11 integrally.

In the shear force transmitting member 50 having such a configuration, the connecting plate 50c faces horizontally below the steel deck 30, and the first fixed plate 50a and the second fixed plate 50b vertically protrude from the connecting plate 50c. Place in state. Then, after the first fixing plate 50a of the shearing force transmitting member 50 is brought into contact with the lower extending vertical rib 32A of the steel slab 30, as shown in FIG. The second fixing plate 50b is brought into contact with the main girder web 11a by bolts 51, and then connected to the main girder web 11a by bolts 52. The connecting plate 50c of the shear force transmitting member 50 is arranged on the lower surface side of the main girder upper flange 11b while being separated from the main girder upper flange 11b. In this way, the main girder 11 and the steel deck 30 are connected by the shear force transmitting member 50 that transmits the shear force in the bridge axis direction.
At this time, as shown in FIG. 15, the liner plate 60 is placed between the lower extending vertical rib 32A on the right side (offset side) and the first fixing plate 50a of the right side (offset side) shear force transmitting member 50. By interposing, the dimensional error in the bridge width direction of the steel deck 30 with respect to the main girder 11 may be absorbed. Further, as shown in FIGS. 15B to 15E, the shear force transmitting member 50 is preliminarily provided with bolt holes 50d for the bolts 51 and 52, and is carried into the site. At the site, using the bolt holes 50d provided in the shearing force transmitting member 50 as a template, drilling is performed on the main girder web 11a and the downwardly extending vertical ribs 32A using a portable drilling machine (not shown). Thereby, the function of adjusting the dimensional error in the vertical direction can be secured on site.
A plurality of shear force transmitting members 50 may be provided at predetermined intervals along the bridge axis direction, and the main girder 11 and the steel slab 30 may be connected by the plurality of shear force transmitting members 50, or one shear force The main girder 11 and the steel slab 30 may be connected by the transmission member 50. Since the total cross-sectional area of the shear resistance cross section of the shear force transmission member 50 influences the shear force transmission, if the shear resistance cross section can be sufficiently secured as the entire shear transmission member, the shear transmission member is made of steel even if it is divided. There is no difference in the combining effect between the floor slab 30 and the main girder 11. However, it is preferable that at least one shear force transmitting member 50 is provided with two or more bolts 51 and 52, respectively, so that the shear force transmitting member 50 does not rotate.

In the present embodiment, as shown in FIG. 12, shear force transmitting members 50 are arranged at positions sandwiching the horizontal ribs 33 of the steel slab 30 in the bridge axis direction. And the steel slab 30.
Further, as shown in FIG. 15, the shear force transmitting members 50 are arranged symmetrically in the bridge width direction with the main girder web 11a of the right main girder 11 interposed therebetween, and one shear force transmitting member 50 is placed on one lower side. The extending longitudinal rib 32A and one web surface of the main girder web 11a are connected by bolts 52, and the other shear force transmitting member 50 is connected to the other lower extending vertical rib 32A and the other web surface of the main girder web 11a. They are connected by bolts 52.

As described above, the main girder 11 and the steel slab 30 are connected by the shearing force transmitting member 50 that mutually transmits the shearing force in the bridge axis direction, so that the bridge girder extends from the main girder 11 to the steel slab 30. Direction shear force can be transmitted.
In addition, by providing a net member 62 at an end opening in the bridge axis direction of a portion surrounded by the shear force transmitting member 50 and the main girder upper flange 11b, birds such as pigeons enter the surrounded portion. Can be prevented.
At this time, as shown in FIG. 15, the liner plate 61 is interposed between the second fixed plate 50b of the shear force transmitting member 50 on the left side (offset side) and the main girder web 11a, so that the main girder 11 is moved. Of the steel slab 30 in the bridge width direction may be absorbed.
Further, the steel slab joining process using the shear force transmitting member 50 may be performed after a pavement process described later, or may be performed simultaneously with the pavement process. That is, since the main girder 11 and the steel slab 30 are synthesized by installing the shear force transmitting member 50, the stress generated in the main girder 11 is greatly reduced. Even in a high state, a short-term traffic load can be borne if the stress is within a design upper limit stress of the steel material forming the main girder 11 and the steel slab 30. Therefore, after the pavement process, it is also possible to perform the installation work of the shear force transmitting member 50 while providing traffic on the steel slab.

Next, as shown in FIGS. 9B and 16, a temporary fixing plate 55 is provided between the steel slab 30 and the reinforced concrete slab 14 adjacent to the steel slab 30 in the bridge width direction and the bridge axis direction. A temporary paved portion 56 is formed on the upper surface side of the temporary fixing plate 55 substantially flush with the paved portion 34 provided on the upper surface of the steel slab 30 and the paved portion 15 on the reinforced concrete slab 14. (Step S11 in FIG. 1). The temporary fixing plate 55 suppresses the depressed state of the road and allows the vehicle to pass by temporarily connecting between the reinforced concrete slab 14 and the steel slab 30 or between adjacent steel slabs. Has a function.
That is, as shown in FIG. 16A, in the reinforced concrete slab removing step described above, of the peripheral portion of the reinforced concrete slab 14 surrounding the removal portion 20 in which the steel slab 30 is disposed, in the bridge width direction. In the adjacent part, a part of the pavement portion 15 is removed on the upper surface side of the main girder upper flange 11b of the main girder 11, and the edge of the reinforced concrete slab 14 adjacent to the removed portion 20 in the bridge width direction is exposed. It has become. The reinforced concrete slab 14 located between the main girders 11 and adjacent in the bridge axis direction has a part of the pavement 15 removed along the bridge width direction, and the bridge axis of the reinforced concrete slab 14 is removed. The edge part adjacent to the removal part 20 in the direction is exposed.
On the other hand, the outer peripheral edge 31a of the deck plate 31 of the steel deck 30 projects outward from the outer peripheral edge of the pavement portion 34, and a plurality of bolt holes 31b are provided in the protruding outer peripheral edge 31a.
In the bridge width direction and the bridge axis direction, a gap S is formed between the outer peripheral edge 31a of the steel slab 30 and the edge (outer peripheral edge 32a) of the reinforced concrete slab 14 along the bridge axis direction and the bridge width direction. Is provided.

  Then, as shown in FIG. 16B, the temporary fixing plate 55 is attached to the outer peripheral edge 31a of the deck plate 31 and the edge 32a of the reinforced concrete floor slab 14 along the bridge axis direction so as to straddle the gap S. Hang over. The temporary fixing plate 55 is provided with a bolt hole 55b, and the temporary fixing plate 55 is bridged so that the bolt hole 55b is coaxial with the bolt hole 31b. Then, the bolt 57 is inserted into the bolt holes 55b and 31b, and the temporary fixing plate 55 is fixed by tightening with the nut 57a. The pavement portion 34 is provided on the upper surface of the slab 30 and the pavement portion 15 on the reinforced concrete slab 14. FIG. 16 shows a case where a temporary fixing plate 55 is bridged over a gap S between an outer peripheral edge 31a of the deck plate 31 and an edge 32a of the reinforced concrete floor slab 14 along the bridge axis direction to provide a temporary pavement portion 56. However, the case where the temporary paving plate 55 is provided over the gap S between the outer peripheral edge 31a of the deck plate 31 and the edge 32a along the bridge width direction of the reinforced concrete floor slab 14 to provide the temporary pavement 56 is also basically applicable. Specifically, the same procedure is performed.

  The floor slab replacement structure of the bridge constructed in this manner is provided on the upper surface side of the main girder upper flange 11b of the main girder 11 in at least a part of the reinforced concrete floor slab 14, as shown in FIG. The remaining reinforced concrete 21 remaining by removing portions other than the portion and at least a part of the reinforced concrete floor slab 14 are removed to the removed portion 20 (see FIG. 6) obtained by removing the remaining reinforced concrete 21 in an exposed state, and to the remaining reinforced concrete 21. And a steel floor slab 30 arranged to cover.

The steel slab 30 is disposed on the lower surface side of the deck plate 31 in the bridge width direction, and at least a part of one end surface or both end surfaces in the bridge width direction is the web surface of the main girder web 11a of the main girder 11 closest to the bridge plate. The horizontal ribs 33 (33A, 33B) oppose the horizontal ribs 33. At the end 33e of the horizontal rib 33, the horizontal rib 33 is attached to the main girder web 11a closest to the end 33e. Rigidly connected.
In addition, as shown in FIG. 12, the main girder 11 and the steel slab 30 are connected by a shear force transmitting member 50 that transmits a shear force in the bridge axis direction.

  The irregular material 47 is filled between the steel slab 30, the main girder upper flange 11b, and the reinforced concrete 21 remaining. Further, a temporary fixing plate 55 is bridged between the steel slab 30 and the reinforced concrete slab 14 adjacent to the steel slab 30, and a temporary pavement portion 56 is formed on the upper surface side of the temporary slab 55. 30 and the pavement 15 on the reinforced concrete floor slab 14 are almost flush with each other.

In this way, after the replacement of one steel deck 30 is completed, the temporary traffic regulation is released, and the construction zone can be passed (step S12 in FIG. 1).
When replacing the second steel slab 30, it is basically performed by sequentially repeating the above-described steps. However, detailed description of each step is omitted.
First, as shown in FIGS. 18 and 19, in the construction zone, of the part of the reinforced concrete slab 14 adjacent to the previously replaced (newly installed) steel slab 30 in the bridge axis direction, the bridge axis direction (Z By removing a portion other than the portion provided on the upper surface side of the main girder upper flange 11b within a predetermined width of the main girder upper flange 11b, the removal portion 20 is provided in a part of the reinforced concrete floor slab 14, and the main portion of the removal portion 20 is The remaining reinforced concrete 21 is left on the upper surface side of the girder upper flange 11b (reinforced concrete floor slab removing step). Further, the horizontal rib mounting member 16 is bolted to the upper part of the main girder web 11a by a high strength bolt.

Next, as shown in FIGS. 20A and 21, the next steel slab 30 is disposed on the removal section 20 so as to cover the remaining reinforced concrete 21 (see FIG. 9), and the height adjustment bolt 40 (see FIG. 11), the height of the steel slab 30 is adjusted (steel slab arranging step).
Next, the lateral ribs 33 of the steel slab 30 are rigidly connected to the main girder web 11a closest to the ends at the ends of the lateral ribs 33 by the lateral rib mounting members 16 (lateral rib rigid connection step).
Further, at this stage, as shown in FIGS. 20G and 20H, the adjacent steel slabs 30, 30 are joined to each other by the high-strength bolts 46 using the inter-panel joint 35. The panel-to-panel joint 35 integrates the adjacent steel slabs 30, 30 by two-plane shear bolt friction welding. By this panel-to-panel joint 35, the bridge axis direction (see FIG. 20G) and the bridge axis perpendicular direction (see FIG. 20H) of the deck plate 31 of the steel slab 30, the vertical rib 32, and the downwardly extending vertical rib 32A (see FIG. 20G) ) Are joined by double shear bolt friction welding. When the inter-panel joint 35 is provided, if there is a temporary fixing plate 55 existing before, the temporary fixing plate 55 is removed.

Further, as shown in FIG. 20G, a panel-to-panel joint 35 that joins steel slabs 30, 30 adjacent to each other in the bridge axis direction (the direction orthogonal to the paper surface in FIG. 20G) is provided on the upper surface side of the deck plate 31. And a joint plate 35a extending in the long side direction (the direction perpendicular to the bridge axis) of the steel slab 30, and between the vertical ribs 32 adjacent to each other in the direction perpendicular to the bridge axis on the lower surface side of the deck plate 31; A plurality of joint plates 35b shorter than the joint plate 35a are provided between the lower extending vertical ribs 32A. The deck plates 31, 31 of the adjacent steel slabs 30, 30 are sandwiched between the joint plates 35a and 35b, and fastened by the high-strength bolts 46, thereby joining the steel slabs 30, 30 together. Have been.
The panel-to-panel joint 35 for joining the vertical ribs 32, 32 of the steel slabs 30, 30 adjacent to each other in the bridge axis direction and the downwardly extending vertical ribs 32A, 32A includes two joint plates 35c, 35c. ing. The joint plate 35c is disposed so as to straddle the joint between the steel slabs 30, 30 adjacent in the bridge axis direction. Then, the vertical ribs 32, 32 and the downwardly extending vertical ribs 32A, 32A of the steel slabs 30, 30 adjacent in the bridge axis direction are sandwiched by the joint plates 35c, 35c, respectively, and fastened by the high-strength bolts 46. The steel slabs 30, 30 are joined together.

As shown in FIG. 20H, the panel-to-panel joint 35 that joins steel slabs 30, 30 adjacent to each other in the direction orthogonal to the bridge axis (the left-right direction in FIG. 20H) includes two joint plates 35d, 35d. I have. The joint plate 35d is arranged so as to straddle the joint of the steel slabs 30, 30 adjacent in the direction orthogonal to the bridge axis, and along the short side direction of the steel slab 30 (the direction orthogonal to the plane of the paper in FIG. 20H). Extending. Then, the deck plates 31, 31 of the steel slabs 30, 30 adjacent to each other in the bridge axis orthogonal manner are sandwiched by the joint plates 35d, 35d, respectively, and fastened by the high-strength bolts 46, whereby the steel slabs 30, 30 are fastened. The two are joined.
Next, the main girder 11 and the steel slab 30 are joined by a shear force transmitting member 50 that transmits a shear force in the bridge axis direction (steel slab joining step).
Before the steel slab joining process, the irregular-shaped material is filled between the steel slab 30, the main girder upper flange 11b, and the remaining reinforced concrete 21.

  Finally, a temporary fixing plate 55 is bridged between the steel slab 30 replaced this time and the reinforced concrete slab 14 adjacent to the steel slab 30 in the bridge width direction and the bridge axis direction. On the upper surface side, the temporary pavement portion 56 is installed substantially flush with the pavement portion 34 provided on the upper surface of the steel slab 30 and the pavement portion 15 on the reinforced concrete slab 14 (see FIG. 16).

  After the next (second) steel slab 30 is replaced in this manner, the necessary number of steel slabs 30 are similarly replaced one after another in the same manner, whereby the reinforced concrete slab 14 is moved a desired distance in the bridge axis direction. And a new steel slab 30 is newly installed. As described above, a new steel slab 30 is newly provided at a desired distance in the bridge axis direction in one of the two lanes on each side.

In addition, after a new steel slab 30 is newly installed in place of the reinforced concrete slab 14 for a desired distance in the bridge axis direction for one lane, as shown in FIG. 20B, the other lane of the two lanes on one side Similarly, for the left lane in FIG. 20B, a new steel slab 30 is newly installed in place of the existing reinforced concrete slab 14.
In FIG. 20B, two steel slabs 30 that have been replaced in one lane are shown. However, in practice, a predetermined number of steel slabs 30 are continuously constructed (newly installed) in the bridge axis direction.
In addition, when the steel slab 30 is newly provided in the other lane, the steel slab 30 is newly provided in the same manner as in the case where the steel slab 30 is newly provided in the one lane. Will be described.

In the case of installing a new steel slab 30 in place of the reinforced concrete slab 14 in the other lane of the two lanes on one side, as a preparatory step, after installing the entire scaffolding and removing interfering members, the reinforced concrete On the lower surface side of the floor slab 14, an operation of bolting the horizontal rib mounting member 16 to the upper part of the main girder web 11a of the predetermined main girder 11 by a high strength bolt is performed.
After regulating upper traffic (not shown) for the other lane, as shown in FIGS. 20B and 20C, the main girder 11 of the main girder 11 of at least a part of the reinforced concrete floor slab 14 of the other lane is used. By removing portions other than the portion provided on the upper surface side of the girder flange 11b, the removal portion 20 is provided on at least a part of the reinforced concrete floor slab 14, and the removal portion 20 is provided on the upper surface side of the main girder upper flange 11b. Remaining reinforced concrete 21 is left (reinforced concrete floor slab removal step).
Next, as shown in FIG. 20D and FIG. 20E, the steel slab 30 is disposed in the removing section 20 so as to cover the remaining reinforced concrete 21 (steel slab arranging step). Next, as shown in FIG. 20E, the lateral ribs 33 are rigidly connected to the main girder web 11a closest to the both ends at the both ends in the bridge width direction of the lateral ribs 33 by the lateral rib attachment members 16 (lateral ribs). Rigid connection process). The horizontal rib mounting member 16 is bolted to the main girder web 11a in advance. When the lateral rib 33 is bolted to the lateral rib attachment member 16, the lateral rib attachment member 16 and the end of the lateral rib 33 are sandwiched by the splice plate 42 and fastened by high-strength bolts.
Next, the main girder 11 and the steel slab 30 are joined by a shear force transmitting member 50 that transmits a shear force in the bridge axis direction (steel slab joining step).

Next, as shown in FIG. 20F, a temporary fixing plate 55 is bridged between the steel slab 30 and the reinforced concrete slab 14 adjacent to the steel slab 30, and the temporary fixing plate 55 The pavement portion 56 is installed substantially flush with the pavement portion 34 on the upper surface side of the steel slab 30 and the pavement portion on the reinforced concrete slab 14. In addition, an inter-panel joint is attached between the steel slab (the steel slab of the other lane) 30 and the steel slab 30 installed in the one lane to join the steel slab to each other. On the upper surface side of the joint, the temporary pavement portion 56 is installed substantially flush with the pavement portion 34 on the upper surface side of the steel slab 30 adjacent in the bridge width direction.
Then, when the replacement of the steel slab 30 is completed in the section planned for the bridge, the entire construction is completed.

In addition, also in the other lane, the covering concrete on the upper part of the remaining reinforced concrete 21 is removed in the reinforced concrete slab removing step.
A height adjusting bolt capable of adjusting the height of the steel slab 30 is screwed to the steel slab 30 so as to be able to abut against the remaining reinforced concrete 21. After the steel slab arranging step, the height is adjusted. Adjust the height of the steel deck by turning the bolts.
Further, after the steel slab arranging step, an irregular material is filled between the steel slab 30, the main girder upper flange 11b, and the remaining reinforced concrete 21.

As described above, according to the present embodiment, the steel slab 30 is disposed in the bridge width direction on the lower surface side of the deck plate 31, and at least a part of one end surface or both end surfaces in the bridge width direction is the closest main plate. The spar 11 has horizontal ribs 33 (33A, 33B) facing the web surface of the main girder web 11a, and the horizontal ribs 33 are rigidly attached to the main girder web 11a closest to the end at the end of the horizontal rib 33. Are combined. That is, unlike the conventional case, the end of the horizontal rib 33 of the steel slab 30 is rigidly connected directly to the main girder web 11a without the intervention of the floor slab support bracket, so that the steel slab 30 and the main girder 11 are integrated. As a bridge having a structure, rigidity as a bridge can be reliably ensured, and labor for mounting a floor slab support bracket to the main girder web 11a and labor for mounting a horizontal rib of a steel slab to the floor slab support bracket. Can be reduced.
In addition, since the main girder 11 and the steel slab 30 are connected by the shear force transmitting member 50 that transmits the shearing force in the bridge axis direction, the shear between the main girder 11 and the steel slab 30 in the bridge axis direction. The force can be transmitted reliably.
Since the horizontal ribs 33 are rigidly connected to the main girder web 11a, the vertical position of the horizontal ribs 33 can be easily adjusted at the time of construction in the case of a back hole method. Of course, if it is known that the necessity of adjusting the position of the lateral rib 33 at the time of construction is small, a hole is formed in a factory or the like as a pre-drilling method, thereby reducing the construction time and labor at the construction site. You can also.

In addition, since it is only necessary to remove the covering concrete 22 above the remaining reinforced concrete 21, it is not necessary to remove the concrete between the studs erected on the main girder upper flange 11b. Since the concrete between the studs is very time-consuming to remove, by leaving the concrete, the time and effort for the removal operation can be greatly reduced.
Moreover, since the reinforced concrete 21 is left on the main girder upper flange 11b, buckling of the main girder 11 can be suppressed when a part of the reinforced concrete floor slab 14 is removed.
Further, since the height of the steel slab 30 can be adjusted by turning the height adjusting bolt 40, the height of the steel slab 30 can be adjusted without changing the reinforced concrete slab 14 or the steel slab 30 previously installed. Can be equal to height. That is, the road surface plan height can be adjusted at the site.

Since the irregular-shaped material 47 is filled between the steel slab 30, the main girder upper flange 11 b, and the reinforced concrete 21, the reinforcing steel of the reinforced concrete 21, the lower surface of the steel slab 30 exposed to the space (space). The corrosion of the upper surface of the main girder upper flange 11b can be prevented.
In addition, a temporary fixing plate 55 is bridged between the steel slab 30 and the reinforced concrete slab 14 adjacent to the steel slab 30, and on the upper surface side of the temporary fixing plate 55, Since the pavement portion 34 of the slab 30 and the pavement portion 15 on the existing reinforced concrete slab 14 are almost flush with each other, the pavement portion 15 of the existing reinforced concrete slab 14 is updated (replaced) with the steel floor. The pavement 34 of the plate 30 can be continuous. For this reason, the lane regulation that was performed when the floor slab was replaced can be released, and the vehicle can be driven temporarily.

Further, since the end of the lateral rib 33 is bolted to the lateral rib mounting member 16 bolted to the main girder web 11a, the end of the lateral rib 33 can be easily connected to the main girder web 11a closest to the end. Rigid connection can be ensured.
Further, since the frictional surface treatment by metal spraying (aluminum spraying) is performed on the joint surface around the bolt hole 42c of the splice plate 42, the friction coefficient necessary for the high-strength bolt frictional joint is secured, and the high-strength bolt 45 is secured. The number can be minimized.
In addition, since the existing reinforced concrete slab 14 is replaced with a steel slab 30 that is much lighter than the reinforced concrete slab 14, the steel slab 30 can be made to protrude outward in the bridge width direction from the reinforced concrete slab 14, The shoulder width of the road can be increased.

(Second embodiment)
Next, a second embodiment will be described.
In the second embodiment, the interval between the main girders adjacent to each other in the bridge width direction is about 2 m to 2.5 m, and a part of the reinforced concrete slab is cut into a long shape in the bridge axis direction and removed. The case of replacing with a steel deck will be described.
In the present embodiment, the process is basically performed by sequentially repeating the steps described in the first embodiment. Therefore, the detailed description of each step is omitted, and the same components as those in the first embodiment are denoted by the same reference numerals, and the description is omitted or simplified.

First, an unillustrated full-length suspension scaffold is installed under the bridge 10 as shown in FIG. 22, and from this full-length suspension scaffold, members that interfere with the installation (replacement) of a new steel deck are removed, improved, Finish (partly grinder work).
Next, as shown in FIG. 23, of the four main girders of the bridge 10, the horizontal rib attaching members 16 are arranged at predetermined intervals in the bridge axis direction above the main girder web 11 a of the two right main girders 11. Bolted with high strength bolts. In this case, the lateral rib mounting members 16 are bolted to both web surfaces of the main girder web 11a of the main girder 11 located on the rightmost side, and the right side of the main girder web 11a of the second main girder 11 from the right. The horizontal rib mounting member 16 is bolted to the web surface.
After attaching the lateral rib attachment member 16 to the main girder 11, if necessary, one-side lane regulation of upper traffic is performed. When performing one-sided lane regulation, temporary guards 17 are erected at predetermined intervals in the bridge axis direction at the center of the road surface in the width direction (bridge width direction).

  Next, as shown in FIG. 24 and FIG. 25, of the reinforced concrete floor slab 14, an overhang bracket 14 </ b> A projecting outward (right side) from the right main girder 11 in the bridge width direction (X direction) (FIG. 22 and FIG. 23) is removed in the bridge axis direction (Z direction) in a rectangular shape in plan view, that is, in such a manner that a portion of the bracket 14A is left at both ends in the bridge axis direction. By removing the right side edge of the reinforced concrete floor slab 14 including the bracket 14A in the bridge width direction, a removed portion 20A is provided in a part of the reinforced concrete floor slab 14, and the right main girder upper flange 11b on the right side in the removed portion 20A. Remaining reinforced concrete 21 is left in the upper half.

Next, as shown in FIGS. 26 and 27, a new steel slab 30A is installed on the removing portion 20A so as to cover the remaining reinforced concrete 21, and a bridge width direction of the lateral rib 33 of the steel slab 30A is used. Is connected to the nearest main girder web 11a in a state where the end surface of the horizontal rib 33 on the main girder 11 side in the bridge width direction faces the web surface of the main girder web 11a of the nearest main girder 11. The rigid connection by the rib attachment member 16 rigidly connects the horizontal rib 33 and the nearest main girder web 11a. Prior to the horizontal rib joining step, the height of the steel slab 30A is adjusted by the above-described height adjusting bolt 40 (not shown).
The steel slab 30A of this embodiment includes five horizontal ribs 33 at predetermined intervals (in the case shown in the figure, at intervals of 2.25 m). The distance between the adjacent horizontal ribs 33 is mainly determined by transportation. If the distance between the main girders is about 2.5 m, the length of the steel slab 30A in the bridge width direction is about 2.5 m or more. Therefore, the interval between the lateral ribs 33 can be made relatively large. At this time, since the maximum length of the steel deck 30A in the bridge axis direction is about 12 m, which is the transport limit, the number of the transverse ribs 33 can be set to five at 2.25 m intervals. However, depending on construction and other conditions, the length of the steel deck in the bridge axis direction can be appropriately set, and horizontal ribs can be arranged at intervals of up to about 2.25 m in the steel deck.

  Next, as shown in FIG. 28 and FIG. 29, a portion of the reinforced concrete slab 14 between the two right main girders 11, 11 is removed in a rectangular shape in plan view, thereby forming a part of the reinforced concrete slab 14. In addition to providing the removing portion 20B, the reinforced concrete 21 is left on the upper surface of the main girder upper flange 11b of the rightmost main girder 11 in the removing portion 20B, and the main girder upper flange 11b of the second main girder 11 from the right is removed. Remaining reinforced concrete 21 is left on the upper half (reinforced concrete slab removal step).

Next, as shown in FIG. 30 and FIG. 31, the next steel floor slab 30B is disposed on the removal portion 20B so as to cover the remaining reinforced concrete 21 (see FIG. 28), and the height adjustment bolt 40 (see FIG. 11), the height of the steel slab 30B is adjusted (steel slab arranging step).
Next, the lateral rib 33 of the steel deck 30B is rigidly connected to the main girder web 11a closest to the end of the lateral rib 33 at the end in the bridge width direction by the lateral rib mounting member 16 (lateral rib rigidity). Bonding step).
Next, as shown in FIG. 32, the rightmost main girder 11 and the steel slab 30A are joined by a shear force transmitting member 50 that transmits shear force in the bridge axis direction, similar to the first embodiment. At the same time, the main girder 11 and the steel slab 30B are joined by a shear force transmitting member 50 that transmits a shear force in the bridge axis direction (steel slab joining step). The attachment of the shear force transmitting member 50 can be performed after the traffic regulation is released.
In addition, the steel decks 30A and 30B adjacent to each other in the direction orthogonal to the bridge axis (the left-right direction in FIG. 32) are joined by the panel joint 35. The panel-to-panel joint 35 includes two joint plates 35d, 35d. The joint plates 35d, 35d are arranged so as to straddle the joints of the steel slabs 30A, 30B adjacent to each other in the direction perpendicular to the bridge axis, and the joint plates 35d, 35d are used to connect the deck plates 31, 31 of the steel slabs 30A, 30B. The steel slabs 30A and 30B are joined together by being pinched and fastened by the high-strength bolts 46, respectively. Further, the pavement portions 34a of the steel slabs 30A and 30B are filled with the pavement portions 34a.
Finally, the temporary fixing plate 55 is bridged between the steel slab 30B replaced this time and the reinforced concrete slab 14 adjacent to the steel slab 30B in the bridge width direction and the bridge axis direction. On the upper surface side, a temporary pavement portion (not shown) is installed substantially flush with the pavement portion 34 previously provided on the upper surfaces of the steel slabs 30A and 30B and the pavement portion 15 on the reinforced concrete slab 14.

After the replacement of the steel slabs 30A and 30B is completed in this way, the temporary traffic regulation is released and the construction zone can be passed.
When the next steel floor slabs 30A and 30B are replaced, the above steps are basically repeated sequentially. Further, the necessary number of steel slabs 30A and 30B are similarly replaced one after another, thereby replacing the reinforced concrete slab 14 with a desired distance in the bridge axis direction and newly installing new steel slabs 30A and 30B.

  According to the present embodiment, the same effect as that of the first embodiment can be obtained. In addition, when the interval between the main girders adjacent to each other in the bridge width direction is as small as about 2 m to 2.5 m, the present embodiment can be efficiently performed. There is an advantage that new steel slabs 30A and 30B can be newly provided in place of the reinforced concrete slab 14.

  In the present embodiment, after the steel slab 30A is installed, the steel slab 30B is installed. On the contrary, even after the steel slab 30B is installed, the steel slab 30A is installed. Good.

(Third embodiment)
Next, a third embodiment will be described.
In the third embodiment, as shown in FIGS. 33 and 34, the bridge 10B is replaced with a first lateral rib attaching member (lateral rib attaching member) instead of the lateral rib attaching member 16 of the bridge 10 of the first embodiment. A member 70 and a second lateral rib mounting member (lateral rib mounting member) 71, and a shear force transmitting member 72 is provided instead of the shear force transmitting member 50.
Note that the bridge 10B may be configured to include three or more horizontal rib attachment members.

The first horizontal rib mounting member 70 and the second horizontal rib mounting member 71 are fixed to the main girder 11 on the left side of the main girder web 11a.
In the present embodiment, a plurality of reinforcing ribs (horizontal ribs) 11e are fixed to the main girder web 11a of the main girder 11. The plurality of reinforcing ribs 11e are arranged on the left web surface of the main girder web 11a so as to be vertically separated from each other. The plurality of reinforcing ribs 11e each extend in the bridge axis direction.
In the bridge 10B, of the plurality of steel slabs 30 adjacent in the replaced bridge width direction, the steel slab 30 located on the right side is also referred to as a steel slab 30C, and the steel slab 30 located on the left side is the steel slab. Also called 30D. An extension member 31c extending downward from the deck plate 31 is fixed to the left end of the deck plate 31 of the steel slab 30C. The extension member 31c is disposed on the left side of the remaining reinforced concrete 21 on which the steel floor slab 30C is put.

  As shown in FIGS. 33 and 35, the first horizontal rib mounting member 70 is configured similarly to the horizontal rib mounting member 16, and includes a fixing plate 70a and a connection plate 70b. The fixing plate 70a is formed in a rectangular plate shape. The fixing plate 70a is arranged so that the thickness direction of the fixing plate 70a is the bridge width direction. The fixing plate 70a is bolted to the main girder web 11a of the main girder 11 by a high-strength bolt (not shown) or the like. The length of the fixing plate 70a in the vertical direction is about half the length of the fixing plate 16a of the horizontal rib mounting member 16 in the vertical direction.

The connection plate 70b is formed in a substantially rectangular plate shape. The connection plate 70b protrudes from the center in the width direction of the fixed plate 70a in a direction orthogonal to the plate surface of the fixed plate 70a. The connection plate 70b is arranged so that the thickness direction of the connection plate 70b is the bridge axis direction. The left end of the connection plate 70b extends to the left end of the extension member 31c of the steel slab 30C. The length of the connecting plate 70b in the vertical direction is substantially the same as the length of the fixing plate 70a in the vertical direction.
A notch 70c is formed at the lower edge of the connection plate 70b. The notch 70c is formed from the end of the connecting plate 70b on the fixed plate 70a side to the intermediate portion of the connecting plate 70b in the bridge width direction.
In this example, a reinforcing rib 70d is fixed to the connecting plate 70b. The reinforcing rib 70d is arranged at an intermediate portion of the connecting plate 70b in the vertical direction, and extends in the bridge width direction. Note that the first lateral rib mounting member 70 may not include the reinforcing rib 70d.
In the present embodiment, the first lateral rib mounting member 70 is arranged between the plurality of reinforcing ribs 11e on the main girder web 11a. In other words, the first lateral rib mounting member 70 is disposed below the uppermost reinforcing rib 11e of the plurality of reinforcing ribs 11e.

The second lateral rib mounting member 71 is configured similarly to the first lateral rib mounting member 70. The second horizontal rib mounting member 71 includes a fixing plate 71a, a connecting plate 71b, and a reinforcing rib 71d configured similarly to the fixing plate 70a, the connecting plate 70b, and the reinforcing rib 70d of the first horizontal rib mounting member 70. In this example, no cutout is formed in the connection plate 71b.
The second horizontal rib mounting member 71 is disposed below the first horizontal rib mounting member 70. In this example, the entirety of the second lateral rib attaching member 71 is disposed below the first lateral rib attaching member 70. The first horizontal rib mounting member 70 and the second horizontal rib mounting member 71 are arranged side by side in the vertical direction.

  Since the horizontal rib mounting members 16 of the first embodiment are vertically divided to form the horizontal rib mounting members 70 and 71, the horizontal rib mounting members 70 and 71 are compared with the bending strength of the horizontal rib mounting members 16. The bending strength of the whole 71 decreases. However, since the horizontal rib mounting members 70 and 71 are shorter in the bridge axis direction than the vertical ribs 32 and the like, the horizontal rib mounting members 16 are moved in the vertical direction as compared with the case where the vertical ribs 32 and the like are divided in the vertical direction. The amount of decrease in the bending strength of the horizontal rib mounting members 70 and 71 formed as a whole is small. In addition, compared to the shear strength of the horizontal rib mounting member 16, there is almost no decrease in the shear strength of the horizontal rib mounting members 70 and 71 as a whole.

In the present embodiment, the vertical length L1 of the main girder web 11a between the main girder upper flange 11b and the first lateral rib mounting member 70 is 224 mm or more.
This length L1 is preferably not more than 38 times the thickness of the main girder web 11a.
If the rib attachment members 70 and 71 are attached below the position of the reinforcing ribs 11e of the main girder 11, the stress generated at the welded portion between the main girder upper flange 11b and the main girder web 11a may cause fatigue. This is because it is sufficiently reduced to a level that does not occur. The position where the reinforcing rib 11e is attached to the main girder 11 is determined by a road bridge specification book (edited by the Japan Road Association). The length L1 is 0.2 times the height of the main girder web 11a when the reinforcing rib 11e is attached to the main girder 11 in one step in the vertical direction, and 0.14 times or more when the reinforcing rib 11e is attached in two steps. Become. When the reinforcing ribs 11e are attached in two stages, the length L1 is 224 mm from the equation (1600 × 0.14), assuming that the height of the main girder web 11a is about 1600 mm. In the case where the reinforcing ribs 11e are one level in the horizontal direction, the height of the main girder web 11a is considered to be about 1500 mm. Therefore, the length L1 is 300 mm from the expression (1500 × 0.2).

Further, in recent years, webs having a thick cross section in which the reinforcing ribs of the main girder are eliminated have been manufactured. Therefore, 224 mm, which is the length L1 of the rib attachment member when the plate height is 9 mm and the girder height is 1600 mm, is set as the minimum separation distance. Therefore, in order to reduce the stress between the main girder upper flange 11b and the main girder web 11a, it is appropriate to secure an interval of 224 mm or more as the length L1.
When buckling is taken into consideration, the maximum buckling strength is not reduced when high strength steel SBHS is used for the main girder web 11a, as described in the specification for road bridges. Setting the width of the non-stiffening section to 38 times the sheet thickness is an appropriate upper limit in terms of design.

  As shown in FIGS. 33 and 34, on the right side of the main girder web 11 a of the main girder 11, a first lateral rib mounting member configured similarly to the first horizontal rib mounting member 70 and the second horizontal rib mounting member 71. 70A and the second lateral rib mounting member 71A are bolted. The first horizontal rib mounting member 70A and the second horizontal rib mounting member 71A are different from the first horizontal rib mounting member 70 and the second horizontal rib mounting member 71 only in the length in the bridge width direction.

  As shown in FIGS. 33 and 35, the extension member 31c of the steel slab 30C, the horizontal rib 33B of the steel slab 30D, and the connection plate 70b of the first horizontal rib attachment member 70 are joined to each other by a first splice plate 75. ing. The first splice plate 75 is formed in a plate shape in which the thickness direction of the first splice plate 75 is the bridge axis direction. When the first splice plate 75 is viewed in the bridge axis direction, the first splice plate 75 has a rectangular shape that is long in the up-down direction. The upper end of the first splice plate 75 is disposed immediately below the deck plate 31 of the steel slabs 30C, 30D. The lower end of the first splice plate 75 extends to the middle of the connection plate 70b in the vertical direction. The extension member 31c, the lateral rib 33B, and the connection plate 70b are joined by a high-strength bolt 76 using a first splice plate 75.

  The horizontal rib 33B of the steel slab 30D, the connection plate 70b of the first horizontal rib mounting member 70, and the connection plate 71b of the second horizontal rib mounting member 71 are joined to each other by a second splice plate 77. The second splice plate 77 is disposed below the first splice plate 75. The upper end of the second splice plate 77 extends in the vertical direction to an intermediate portion of the connection plate 70b. A gap T1 is formed between the second splice plate 77 and the first splice plate 75. The lower end of the second splice plate 77 extends up and down to the lower end of the connection plate 71b. The horizontal rib 33B, the connection plate 70b, and the connection plate 71b are joined by a high-strength bolt 78 using a second splice plate 77.

That is, the connection plate 70b is joined to the horizontal rib 33B via the first splice plate 75 and the second splice plate 77, respectively. The gap T1 is disposed in the middle of the connecting plate 70b in the vertical direction.
On the other hand, the first horizontal rib mounting member 70A and the second horizontal rib mounting member 71A and the horizontal rib 33A of the steel floor slab 30C are joined by a splice plate 77A.

As shown in FIG. 36, the pair of shear force transmitting members 72 are arranged so as to sandwich the main girder web 11a in the bridge width direction. As shown in FIGS. 34 and 36, each shear force transmitting member 72 includes a first piece 80, a second piece 81, and a connecting piece 82. The first piece 80 and the second piece 81 are formed in a plate shape in which the bridge width direction is the thickness direction.
The first piece 80 is fixed to the main girder web 11a by a high-strength bolt (first fixing member) 84. Although not shown, the first piece 80 is fixed to the main girder web 11a by a plurality of high-strength bolts 84 arranged at intervals in the bridge axis direction.
The second piece 81 is fixed to the lower extending vertical rib 32A of the steel deck 30C by a high-strength bolt (second fixing member) 85. The second piece 81 is arranged outside a pair of lower extending vertical ribs 32A sandwiching the remaining reinforced concrete 21 in the bridge width direction. The high-strength bolt 85 is arranged at the same position in the vertical direction as the high-strength bolt 84.
The second piece 81 is fixed to the lower extending vertical rib 32A by a plurality of high-strength bolts 85 arranged at intervals in the bridge axis direction.

When the connecting piece 82 is viewed in the bridge axis direction, the connecting piece 82 is formed in a curved shape that protrudes downward. A first end of the connecting piece 82 is connected to the first piece 80. A second end of the connecting piece 82 opposite to the first end is connected to the second piece 81. The connecting piece 82 straddles the lower end of the lower extending vertical rib 32A in the bridge width direction.
The first piece 80, the second piece 81, and the connecting piece 82 are integrally formed by, for example, bending a steel plate.
By fixing the shear force transmission member 72 to the main girder 11 and the downwardly extending vertical rib 32A of the steel slab 30C in this manner, when the steel slab 30C is displaced relative to the main girder 11 in the bridge width direction. The use of the liner plates 60, 61 and the like makes it easier to respond.

The method for replacing the floor slab of the bridge according to the present embodiment for configuring the bridge 10B configured as described above is as follows.
In the present embodiment, the process is basically performed by sequentially repeating the steps described in the first embodiment. Therefore, the detailed description of each step is omitted, and the same components as those in the first embodiment are denoted by the same reference numerals, and the description is omitted or simplified.
In the reinforced concrete floor slab removing step, the first horizontal rib mounting member 70 and the second horizontal rib mounting member 71 are respectively bolted to the main girder web 11a of the main girder 11. At this time, the second horizontal rib mounting member 71 is disposed below the first horizontal rib mounting member 70. The horizontal rib mounting members 70 and 71 are arranged such that the vertical length L1 of the main girder web 11a between the main girder upper flange 11b and the first horizontal rib mounting member 70 is 224 mm or more of the main girder web 11a. It is bolted to the main girder web 11a.
It is assumed that the steel slabs 30C and 30D have been replaced in the bridge 10B by performing the above-described steps.

  In the horizontal rib rigid connection step after the steel floor slab disposing step, the horizontal ribs 33B of the steel floor slab 30D are bolted to the first horizontal rib mounting member 70 and the second horizontal rib mounting member 71, respectively. More specifically, the extension member 31c of the steel slab 30C, the horizontal rib 33B of the steel slab 30D, and the connection plate 70b of the first horizontal rib mounting member 70 are joined to each other by the first splice plate 75. The horizontal rib 33B of the steel floor slab 30D, the connection plate 70b of the first horizontal rib mounting member 70, and the connection plate 71b of the second horizontal rib mounting member 71 are joined to each other by the second splice plate 77.

In the steel deck slab joining step, the first piece 80 of the shear force transmitting member 72 is fixed to the main girder web 11a of the main girder 11 with the high-strength bolt 84. The second piece 81 of the shearing force transmission member 72 is fixed to the vertically extending vertical rib 32A of the steel slab 30C with the high-strength bolt 85.
By performing the above steps, all the steps of the method of replacing the floor slab of the bridge 10B are completed.

Here, the result of analyzing the stress acting on the bridge 10B will be described.
FIG. 37 shows an analysis model of the bridge 10B. In the bridge 10B of the analysis model, a notch 71c is formed at an upper edge of the connection plate 71b. However, it has been found that the notch 71c does not significantly affect the stress acting on the bridge 10B.
In the bridge 10B, the length L1 in the vertical direction of the main girder web 11a between the main girder upper flange 11b and the first lateral rib mounting member 70 is relatively long, and the length L1 is equal to 0 of the height of the main girder web 11a. It is 300 mm which is twice as large. This 0.2 times is determined according to the mounting position in the case where the reinforcing rib specified in the specification for road bridges is one step.
Referring to the Road Bridge Specification, the elastic modulus (Young's modulus) E of the members made of steel such as the steel decks 30C and 30D and the main girder 11 is 200 kN / mm ² , and the Poisson's ratio μ is 0.3. did. The amorphous material 47 was mortar, the elastic modulus E was 26.5 kN / mm ² , and the Poisson ratio μ was 0.167.

A predetermined wheel load was applied to the bridge 10B downward. At this time, the stress range at the position P1 where the main girder web 11a was joined to the main girder upper flange 11b was 20.6 N / mm ² . Since the position P1 is a portion to be welded, it is important to reduce the stress range and improve the fatigue resistance of the main girder 11. In addition, the position P2 of the upper end of the first horizontal rib mounting member 70 on the main girder web 11a is a portion joined by metal touch. Therefore, the stress range at the position P2 is not important as fatigue resistance.
Further, the stress range at the position P3 between the first splice plate 75 and the second splice plate 77 in the outer edge of the horizontal rib 33B was 35.0 N / mm ² .

FIG. 38 shows an analysis model of a bridge 10C in which the length L2 in the vertical direction of the main girder web 11a between the main girder upper flange 11b and the first horizontal rib mounting member 70 is relatively short with respect to the bridge 10B. The length L2 is about 0 to 100 mm, which is at most ten times the thickness of the main girder web 11a. In the bridge 10C, the first splice plate 75 is not further joined to the first lateral rib attachment member 70.
The same wheel load as that applied to the bridge 10B was applied to the bridge 10C. At this time, the stress range at the position P1 where the main girder web 11a was joined to the main girder upper flange 11b was 92.5 N / mm ² . That is, in the bridges 10B, by increasing the length L1 with respect to the bridge 10C, the stress range in the position P1 is found to be smaller from 92.5N / mm ² to 20.6N / mm ^2.
The stress range at the position P3 between the first splice plate 75 and the second splice plate 77 among the outer edges of the horizontal rib 33B was 142.6 N / mm ² . That is, in the bridges 10B, by making also joining the second splice plate 77 with respect to the bridge 10C to the first lateral rib attachment member 70, the stress range in the position P3 is 142.6N / mm ² from 35.0 N / mm ² It turned out to be smaller.

According to the present embodiment, the same effect as that of the first embodiment can be obtained.
Further, by setting the length L1 of the main girder web 11a between the main girder upper flange 11b and the first horizontal rib mounting member 70 to 224 mm or more, the position of the main girder web 11a joined to the main girder upper flange 11b. The stress range of the portion corresponding to P1 can be reduced, and the fatigue resistance of the main girder 11 can be improved.
As the horizontal rib mounting member, a first horizontal rib mounting member 70 and a second horizontal rib mounting member 71 are provided. Therefore, since the entire lateral rib mounting members 70 and 71 can be configured to have predetermined bending strength and shearing resistance, the mass per one of the first horizontal rib mounting member 70 and the second horizontal rib mounting member 71 is reduced. be able to. This allows the operator to easily carry each of the first horizontal rib mounting member 70 and the second horizontal rib mounting member 71 manually.
The first horizontal rib mounting member 70 smaller than the horizontal rib mounting member 16 can be arranged in a narrow place between the reinforcing ribs 11e of the main girder 11.

The first splice plate 75 joins the horizontal rib 33B of the steel floor slab 30D and the first horizontal rib mounting member 70, and the second splice plate 77 forms the horizontal rib 33B of the steel floor slab 30D, the first horizontal rib mounting member 70, and The second lateral rib mounting member 71 is joined. Since the second splice plate 77 joins not only the second lateral rib attachment member 71 but also the first lateral rib attachment member 70, a portion of the lateral rib 33B located between the first splice plate 75 and the second splice plate 77. The stress can be prevented from being concentrated on the substrate.
In the shearing force transmitting member 72, the first piece 80 is fixed to the main girder web 11a by the high strength bolt 84, and the second piece 81 is fixed to the lower extending vertical rib 32A of the steel floor slab 30C by the high strength bolt 85. Since the position to be fixed is the same in the vertical direction, generation of a moment about the axis along the horizontal plane in the shear force transmitting member 72 is suppressed. For this reason, it is less necessary for the shear force transmitting member 72 to withstand the moment, so that the weight of the shear force transmitting member 72 can be reduced, and the number of bolts required for installation can be reduced.

In this embodiment, the first splice plate 75 includes the extension member 31c of the steel slab 30C, the horizontal rib 33B of the steel slab 30D, the connecting plate 70b of the first horizontal rib mounting member 70, and the second horizontal rib mounting member. The connecting plates 71b of the first 71 may be joined, and the second splice plate 77 may join the lateral ribs 33B of the steel slab 30D and the joining plate 71b of the second lateral rib mounting member 71.
Even with such a configuration, the same effects as those of the bridge 10B and floor slab replacement method of the present embodiment can be achieved.
Further, like a bridge 10D shown in FIG. 39, the first splice plate 75 and the second splice plate 77 in the bridge 10B of the present embodiment may be integrally formed as a splice plate 88.

10, 10B, 10C, 10D Bridge (Bridge structure)
DESCRIPTION OF SYMBOLS 11 Main girder 11a Main girder web 11b Main girder upper flange 14 Reinforced concrete floor slab 15 Pavement part 16 Horizontal rib mounting member 18 High strength bolt 20, 20A, 20B Removal part 21 Remaining reinforced concrete 22 Covering concrete 30, 30A, 30B Steel floor slab 31 Deck plate 32 Vertical rib 32A Lower vertical rib (rib)
33 (33A, 33B) Lateral rib 33a One end face 33d Both end faces 33e End 34 Pavement 42, 42A, 77A, 88 Splice plate 42c Bolt hole 45 High strength bolt 47 Irregular material 50, 72 Shear force transmitting member 55 Temporary fixing Plate 56 Temporary pavement 70 First horizontal rib mounting member (horizontal rib mounting member)
71 Second horizontal rib mounting member (horizontal rib mounting member)
75 first splice plate 77 second splice plate 80 first piece 81 second piece 82 connecting piece 84 high strength bolt (first fixing member)
85 High-strength bolt (second fixing member)
L1 length

Claims (24)

A bridge structure constructed by replacing a part of the reinforced concrete slab supported and laid by the main girder of the bridge with a steel slab,
Of the reinforced concrete floor slabs, the remaining reinforced concrete remaining except for the portion provided on the upper surface side of the main girder upper flange of the main girder,
In the reinforced concrete slab, a removing portion formed by removing a portion other than a portion provided on the upper surface side of the main girder upper flange of the main girder, a steel slab arranged to cover the remaining reinforced concrete. Prepared,
The steel deck has lateral ribs arranged in the bridge width direction on the lower surface side of the deck plate,
At least a part of one end face or both end faces in the bridge width direction of the transverse rib faces a web surface of a main girder web of the main girder closest thereto,
The cross rib is rigidly connected to the main girder web closest to the end at the bridge width direction end of the cross rib,
The bridge structure, wherein the main girder and the steel slab are connected by a shear force transmitting member that transmits a shear force in a bridge axis direction.   The bridge structure according to claim 1, wherein the covering concrete on the upper part of the remaining reinforced concrete is removed.   3. The bridge according to claim 1, wherein a height adjusting bolt capable of adjusting the height of the steel slab is screwed to the steel slab so as to abut on the remaining reinforced concrete. 4. Construction.   The bridge structure according to any one of claims 1 to 3, wherein an irregular material is filled between the steel slab, the main girder upper flange, and the remaining reinforced concrete. A pavement section is previously constructed on the steel slab provided in the removing section, and a temporary fixing plate is bridged between the steel slab and the reinforced concrete slab adjacent to the steel slab,
The temporary pavement part is constructed almost flush with the pavement part and the pavement part on the reinforced concrete slab on the upper surface side of the temporary fixing plate, according to any one of claims 1 to 4, wherein Bridge structure as described.   The horizontal rib mounting member is bolted to the main girder web, and an end of the horizontal rib is bolted to the horizontal rib mounting member. Bridge structure.   The bridge structure according to claim 6, wherein the length of the main girder web between the main girder upper flange and the lateral rib mounting member in the vertical direction is 224 mm or more. The lateral rib mounting member and the end of the lateral rib are sandwiched by a splice plate and fastened by a high-strength bolt to be frictionally joined by a high-strength bolt,
8. The bridge structure according to claim 6, wherein a joint surface around the bolt hole of the splice plate around which the high-strength bolt is inserted is subjected to a friction surface treatment by metal spraying.   The bridge structure according to any one of claims 6 to 8, comprising a plurality of the lateral rib attachment members. As the lateral rib mounting member,
A first lateral rib mounting member,
A second horizontal rib mounting member disposed below the first horizontal rib mounting member,
A first splice plate that joins the lateral rib and the first lateral rib mounting member to each other;
A second splice plate that joins the horizontal rib, the first horizontal rib mounting member, and the second horizontal rib mounting member to each other;
The bridge structure according to any one of claims 6 to 9, comprising: As the lateral rib mounting member,
A first lateral rib mounting member,
A second horizontal rib mounting member disposed below the first horizontal rib mounting member,
A first splice plate that joins the lateral rib, the first lateral rib attaching member, and the second lateral rib attaching member to each other;
A second splice plate that joins the lateral rib and the second lateral rib mounting member to each other;
The bridge structure according to any one of claims 6 to 9, comprising: The shear force transmitting member,
A first piece fixed to the main girder web by a first fixing member;
A second piece fixed to a rib bonded to a lower surface of the deck plate by a second fixing member arranged at a position equivalent to the first fixing member in the vertical direction;
A connecting piece connected to the first piece and the second piece, respectively;
The bridge structure according to any one of claims 1 to 11, further comprising: A method of replacing a slab of a bridge in which part of a reinforced concrete slab laid and supported by a main girder of the bridge is replaced with a steel slab,
The steel deck has horizontal ribs arranged in the bridge width direction on the lower surface side of the deck plate, and at least a part of one end surface or both end surfaces in the bridge width direction of the horizontal ribs is the closest main girder. It faces the web surface of the main girder web,
By removing a portion of the reinforced concrete slab other than the portion provided on the upper surface side of the main girder upper flange of the main girder, a removing portion is provided and the remaining reinforced concrete is left on the upper surface side of the main girder upper flange. Reinforced concrete slab removal process,
In the removing section, a steel slab arranging step of arranging a steel slab so as to cover the remaining reinforced concrete,
A transverse rib rigid connection step of rigidly coupling the transverse rib to the main girder web closest to the end at the end of the transverse rib;
A steel slab coupling step of coupling the main girder and the steel slab with a shear force transmitting member that transmits a shear force in a bridge axis direction;
A method of replacing a floor slab of a bridge, comprising:   14. The method of replacing a bridge slab according to claim 13, wherein in the reinforced concrete slab removing step, the covering concrete on the upper part of the remaining reinforced concrete is removed. A height adjustment bolt capable of adjusting the height of the steel slab is screwed into the steel slab so as to be in contact with the remaining reinforced concrete,
The method according to claim 13, wherein the height of the steel slab is adjusted by turning the height adjusting bolt after the steel slab arranging step.   16. An irregular-shaped material is filled between the steel slab, the main girder upper flange, and the remaining reinforced concrete after the steel slab arranging step. The method of replacing the floor slab of the bridge described in. A pavement section is constructed on the steel slab provided in the removing section,
After the steel slab arranging step, a temporary fixing plate is bridged between the steel slab and the reinforced concrete slab adjacent to the steel slab and not replaced with the steel slab,
17. The temporary pavement part is constructed on the upper surface side of the temporary fixing plate so as to be substantially flush with the pavement part and the pavement part on the reinforced concrete floor slab. How to replace the bridge slab.   18. The horizontal rib mounting member is bolted to the main girder web, and the horizontal rib is bolted to the horizontal rib mounting member after the steel slab arranging step. The method for replacing a floor slab of a bridge according to any one of the preceding claims.   19. The method according to claim 18, wherein the length of the main girder web between the main girder upper flange and the horizontal rib mounting member in the vertical direction is 224 mm or more. When bolting the lateral rib to the lateral rib mounting member,
High-strength bolt frictionally joined by clamping the lateral rib mounting member and the end of the lateral rib with a splice plate and fastening with a high-strength bolt,
20. The method according to claim 18, wherein a joint surface around the bolt hole of the splice plate in which the high-strength bolt is inserted is subjected to a friction surface treatment by metal spraying in advance.   A plurality of the lateral rib mounting members are bolted to the main girder web, and the lateral ribs are bolted to the plurality of lateral rib mounting members, respectively, after the steel slab arranging step. The method for replacing a floor slab of a bridge according to any one of claims 18 to 20. A first lateral rib mounting member that is the lateral rib mounting member, and a second lateral rib mounting member disposed below the first lateral rib mounting member are bolted to the main girder web;
In the transverse rib rigid connection step,
The first splice plate joins the lateral rib and the first lateral rib mounting member to each other,
The bridge floor according to any one of claims 18 to 21, wherein a second splice plate connects the horizontal rib, the first horizontal rib mounting member, and the second horizontal rib mounting member to each other. Plate replacement method. A first lateral rib mounting member that is the lateral rib mounting member, and a second lateral rib mounting member disposed below the first lateral rib mounting member are bolted to the main girder web;
In the transverse rib rigid connection step,
The first splice plate joins the lateral rib, the first lateral rib attaching member, and the second lateral rib attaching member to each other,
The method according to any one of claims 18 to 21, wherein the lateral rib and the second lateral rib mounting member are joined to each other by a second splice plate. In the steel slab joining step,
A first piece of the shear force transmitting member is fixed to the main girder web by a first fixing member,
A second piece of the shear force transmitting member is fixed to a rib attached to a lower surface of the deck plate by a second fixing member disposed at a position equivalent to the first fixing member in the vertical direction,
The method according to any one of claims 13 to 23, wherein the connecting pieces of the shear force transmitting member are connected to the first piece and the second piece, respectively.

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