JP2019206902A - Bridge structure and floor slab replacing method - Google Patents

Abstract

To provide a bridge structure and a floor slab replacing method capable of easily and firmly connecting a horizontal rib of a steel floor slab to a main girder web, and reliably transmitting a shear force between the main girder and the steel floor slab in the direction of a bridge axis.SOLUTION: The bridge structure includes: remaining reinforced concrete 21 that is left by removing a part other than a part provided on an upper surface side of a main girder upper flange 11b of a reinforced concrete floor slab 14; a removal part 20 formed by removing the part other than the part provided on the upper surface side of the main girder upper flange 11b; and a steel floor slab 30 arranged on the removal section 20 to cover the remaining reinforced concrete 21. The steel floor slab 30 includes a lateral rib 33 disposed on a lower surface side of a deck plate 31 and having one end surface or both end surfaces in the bridge width direction facing a web surface of a main girder web 11a of a nearest main girder 11. An end of the lateral rib 33 is rigidly connected to the nearest main girder web 11a, and the main girder 11 and the steel floor slab 30 are connected by a shearing force transmission member 50.SELECTED DRAWING: Figure 17

Description

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

  For bridges used on highways, etc., it may be necessary to replace the floor slabs of aging roads. Conventionally, when an RC floor slab (reinforced concrete floor slab) of a bridge is replaced with a new floor slab, the existing reinforced concrete floor slab is first removed. Next, the main girder upper flange of the main girder is completely smoothed and then the studs are re-struck, or when replacing the RC floor slab with a steel slab, a bolt hole is made in the main girder upper flange of the main girder. I try to do it.

  However, the conventional methods have the following problems. (1) Removing a reinforced concrete floor slab with studs requires a lot of labor and time. (2) When removing concrete between studs, noise, vibration and dust problems may occur. (3) If the reinforced concrete floor slab is completely removed, buckling may occur at the upper flange of the main girder, especially in the case of a composite floor slab. (4) If the reinforced concrete slab is removed, the dead load of the bridge will be less than half, so the deflection of the girder will be reduced, and various dimensional adjustments will be required to maintain the same planned route height as the original. (5) If a new floor slab is installed according to the current standards, the weight will increase compared to the original structure. For this purpose, it is necessary to reinforce the girders, piers, and in some cases piles (it is necessary to increase not only the thickness but also the width).

  For example, a method described in Patent Document 1 is known as an example of a bridge floor slab replacement method for solving such a problem. In the floor slab replacement method described in Patent Document 1, in order to replace a reinforced concrete floor slab supported by a main girder of a bridge with a steel floor slab, the steel slab is disposed at a position where the reinforced concrete floor slab is removed. In the bridge slab replacement method, a floor slab support bracket is attached to the main girder at an appropriate interval below the reinforced concrete floor slab, and a portion of the reinforced concrete floor slab located on the upper flange of the main girder is attached. The remaining portion of the main girder is removed by removing the removed portion, and the horizontal portion of the steel floor slab having a lateral rib arranged so as to avoid the residual portion is provided instead of the removed reinforced concrete floor slab. Ribs are arranged, and the lateral ribs are mounted on the floor slab support bracket.

JP-A-2006-194215

However, in the floor slab replacement method described in Patent Document 1, the floor slab support bracket is attached to the main girder web by welding or the like. Since the horizontal rib is attached to the floor slab support bracket by welding or the like, it takes time to attach to the horizontal rib.
In addition, the horizontal ribs of the steel slab are mounted on the floor slab support bracket mounted on the floor slab support bracket, but basically this floor 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 high strength. In addition, since it is difficult to design the lateral rib as a continuous beam, a larger cross section may be required. Moreover, since it is attached to the main girder only through the floor slab support bracket, it is difficult to transmit shearing force in the direction of the bridge axis between the main girder and the steel deck. Therefore, it is difficult to form a bridge with an integrated structure in which the steel slab and the main girder are combined, and the strength as a bridge may be insufficient.
Also, because the horizontal ribs are placed on the brackets, when the concrete slab is removed, the deflection of the bridge decreases and the installation height of the horizontal ribs increases. May be possible.

  The present invention has been made in view of the above circumstances, and can easily and firmly join the horizontal ribs of the steel deck to the main girder web, and can ensure rigidity and strength as a bridge. Bridge structure and floor slab replacement method that makes it possible to synthesize a girder and floor slab by reliably transmitting shear force in the direction of the bridge axis with the slab, and also makes it easy to adjust the position of the lateral 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 constructed by replacing a part of a reinforced concrete floor slab supported by a main girder of a bridge with a steel slab. And
Of the reinforced concrete floor slab, the remaining reinforced concrete that is left and removed except the part provided on the upper surface side of the main girder upper flange of the main girder,
Of the reinforced concrete slab, a steel slab disposed so as to cover the remaining reinforced concrete on a removal portion formed by removing the portion other than the portion provided on the upper surface side of the upper girder upper flange of the main girder Prepared,
The steel slab 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 surface or both end surfaces of the lateral rib in the bridge width direction is opposed to the web surface of the main girder web of the main girder,
The lateral rib is rigidly coupled to the main girder web closest to the end at the end of the lateral rib in the bridge width direction,
The main girder and the steel deck are connected by a shearing force transmission member that transmits a shearing force in the direction of the bridge axis.

The bridge slab replacement method of the present invention is a bridge slab replacement method for replacing a part of a reinforced concrete floor slab supported by a main girder of a bridge with a steel slab,
The steel slab has a lateral rib 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 of the lateral rib in the bridge width direction is the nearest of the main girder. It faces the web surface of the main girder web,
By removing portions other than the portion provided on the upper surface side of the main girder upper flange of the main girder in the reinforced concrete floor slab, the removal portion is provided and the remaining reinforced concrete is left on the upper surface side of the main girder upper flange. Reinforced concrete floor slab removal process,
A steel floor slab placement step of placing the steel floor slab on the remaining reinforced concrete on the removal portion;
A lateral rib rigid coupling step of rigidly coupling the lateral rib at the end of the lateral rib to the main girder web closest to the end; and
A steel slab coupling step of coupling the main girder and the steel slab by a shearing force transmission member that transmits a shearing 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 the web surface of the main girder web of the main girder nearest to the deck plate. The horizontal rib is rigidly coupled to the main girder web closest to the end at the end of the horizontal rib in the bridge width direction. Since the end of the transverse rib of the plate is rigidly connected directly to the main girder web without the floor support bracket, the steel deck can be designed with a reasonable transverse rib section. As a result, it is possible to reduce the structural weight as compared with the case where a conventional floor slab support bracket is used.
In addition, since the main girder and the steel deck are connected by a shearing force transmission member that transmits the shearing force in the bridge axis direction, the shearing force is reliably ensured in the bridge axis direction between the main girder and the steel deck. It can be transmitted, and a structure in which the steel slab and the main girder are combined can be ensured.

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 covered concrete on the upper part 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 covered concrete on the upper part of the remaining reinforced concrete, so there is no need to remove the concrete between the studs standing on the main girder upper flange. . Since the concrete between the studs requires much labor to remove, leaving the concrete can greatly reduce the labor of the removal work. The reason for removing the top covered concrete is to secure a space for adjusting the road surface height and facilitate the removal of the asphalt portion existing on the steel deck.

In the bridge structure of the present invention, a height adjusting bolt capable of adjusting the height of the steel slab may be screwed to the steel slab so as to be in contact with the remaining reinforced concrete.
Furthermore, 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 onto the steel slab so as to come into contact with the remaining concrete, You may adjust the height of the said steel deck by turning the said height adjustment volt | bolt after an arrangement | positioning process.

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

Moreover, in the bridge structure of the present invention, an amorphous 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, an irregularly shaped material may be filled between the steel floor slab, the main girder upper flange, and the remaining reinforced concrete after the steel floor slab placement step.
In addition, as long as it is after the steel plate slab arrangement | positioning process, you may perform filling of an amorphous material before a steel plate slab coupling | bonding process.

According to such a bridge structure and floor slab replacement method, since the amorphous material is filled between the steel slab, the main girder flange, and the remaining reinforced concrete, the rebar of the remaining reinforced concrete is placed in the space (space). Corrosion on the lower surface of the exposed steel deck and the upper surface of the main girder upper flange can be prevented.
It is not necessary to obtain a large strength for this amorphous material. In the first place, the remaining reinforced concrete part was also concrete that was cast in an era when there was not enough construction technology, and since it was shared for a long time, it was difficult to guarantee the strength enough for reliable design. Therefore, it is not necessary to obtain a large strength for the amorphous material filled therein.

Further, in the structure of the bridge of the present invention, a pavement portion is preliminarily constructed on the steel floor slab disposed in the removal portion, the steel floor slab is adjacent to the steel floor slab, and the steel floor slab. A temporary fixing plate is bridged between the reinforced concrete floor slabs that have not been replaced by the temporary fixing plate, and the temporary pavement portion is substantially flush with the pavement portion and the pavement portion on the reinforced concrete floor slab. It may be constructed.
Furthermore, in the floor slab replacement method of the present invention, a pavement is preliminarily constructed on the steel floor slab disposed in the removal portion, and after the steel floor slab disposition step, the steel floor slab and the A temporary fastening plate is bridged between the reinforced concrete slab adjacent to the steel slab, and the temporary paved portion is substantially flush with the paved portion and the paved portion on the reinforced concrete slab on the upper surface side of the temporary fastening plate. It may be applied to.

  According to such bridge structure and floor slab replacement method, the temporary pavement is constructed on the upper surface side of the temporary fixing plate, almost flush with the pavement of the steel slab and the existing reinforced concrete slab. Therefore, the existing reinforced concrete slab pavement and the renewed (replaced) steel slab pavement can be connected. For this reason, it is possible to cancel the lane restriction that has been performed at the time of replacement of the floor slab and allow the vehicle to travel 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 the horizontal rib is bolted to the horizontal rib mounting member after the steel floor slab installation step. May be.

  According to such a bridge structure and a floor slab replacement method, since the end of the lateral rib is bolted to the lateral rib mounting member bolted to the main girder web, the end of the lateral rib is connected to the end Can be easily and securely rigidly coupled to the nearest main girder web.

In the bridge structure of the present invention, a length in the vertical direction of the main girder web between the main girder upper flange and the lateral rib mounting member may be 224 mm or more.
Furthermore, in the floor slab replacement method of the present invention, the vertical length of the main girder web between the main girder upper flange and the lateral 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 to improve the fatigue resistance of the main girder.

Further, in the bridge structure of the present invention, the horizontal rib mounting member and the end portion of the horizontal rib are sandwiched by a splice plate and fastened by a high strength bolt to be frictionally joined by the high strength bolt. A friction surface treatment by metal spraying may be applied to the joint surface around the bolt hole through which the high-strength bolt of the plate is inserted.
Furthermore, 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. It is possible to perform frictional surface treatment by metal spraying on the joint surface of the splice plate around the bolt hole through which the high-strength bolt is inserted.

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

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

  According to such a bridge structure and a floor slab replacement method, since it can be configured to have a predetermined bending strength and shear strength over the plurality of horizontal rib mounting members, the mass per one of the plurality of horizontal rib mounting members Can be lightened. Thereby, an operator can carry easily each horizontal rib attachment member manually.

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 that joins the transverse rib and the first transverse rib attachment member to each other; a second splice plate that joins the transverse rib, the first transverse rib attachment member and the second transverse rib attachment member to each other; May be provided.
Furthermore, in the floor slab replacement method of the present invention, 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 on the main girder web. The mounting member is bolted, and in the rigid rib rigid coupling step, the lateral rib and the first lateral rib mounting member are joined to each other by a first splice plate, and the lateral rib, the first The lateral rib attachment member and the second lateral rib attachment member may be joined to each other.

  According to such a bridge structure and a floor slab replacement method, not only the second lateral rib mounting member but also the first lateral rib mounting member are joined by the second splice plate. It is possible to avoid stress concentration in a portion located between the splice plate.

Moreover, in the structure of the bridge 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 that joins the transverse rib, the first transverse rib attachment member and the second transverse rib attachment member to each other; a second splice plate that joins the transverse rib and the second transverse rib attachment member to each other; May be provided.
Furthermore, in the floor slab replacement method of the present invention, 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 on the main girder web. A mounting member is bolted, and in the lateral rib rigid coupling step, the lateral rib, the first lateral rib mounting member, and the second lateral rib mounting member are joined to each other by a first splice plate, and a second splice plate is used. 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 are joined by the first splice plate. It is possible to avoid stress concentration in a portion located between the splice plate.

In the bridge structure of the present invention, the shear force transmission 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. You may provide the 2nd piece fixed by the 2nd fixing member arrange | positioned in the position equivalent in the up-down direction with one fixing member, and the connection piece connected with the said 1st piece and the said 2nd piece, respectively.
Further, in the floor slab replacement method of the present invention, in the steel floor slab coupling step, the first piece of the shear force transmitting member is fixed to the main girder web by a first fixing member, and is attached to the 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 the same position in the vertical direction as the first fixing member, and the connecting piece of the shear force transmitting member is The first piece and the second piece may be connected to each other.

  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 equal in the vertical direction, the moment around the axis line along the horizontal plane is prevented from occurring in the shearing force transmitting member. For this reason, it is less necessary for the shearing force transmission member to withstand the moment, and the shearing force transmission member can be reduced in weight.

  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 girder can be secured between the main girder and the steel deck. Shear force can be transmitted reliably.

It is an operation | work flowchart of the floor slab replacement | exchange method of the bridge concerning the 1st Embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view illustrating a bridge slab replacement method 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. It is the perspective view which looked at the bridge before a floor slab replacement from diagonally downward. The state which shows the state which attached the horizontal rib attachment member to the main girder web similarly, (a) is the perspective view which looked at the bridge from diagonally downward, (b) is sectional drawing containing the horizontal rib attachment member of the right main girder It is. The horizontal rib attachment member is shown, (a) is a perspective view of the horizontal rib attachment member, and (b) is an A arrow view in (a). 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. 2 is a perspective view showing a state in which a part of a reinforced concrete slab is removed, and a bridge viewed obliquely from above. FIG. 3 is a perspective view showing a state in which a part of a reinforced concrete slab is removed, and a bridge viewed obliquely from below. It is sectional drawing which shows the state which removed the remaining concrete same as the above. The same shows the state in which the steel slab is installed, (a) is a perspective view of the bridge as seen from diagonally above, (b) is the perspective view of the bridge as shown in FIG. It is. The state which installed the steel floor slab is shown, (a) is the perspective view which looked at the bridge from diagonally downward, (b) is the front view of a bridge. The main part containing residual concrete is shown, (a) is sectional drawing, (b) is sectional drawing which shows the state filled with the amorphous material. FIG. 2 shows a state in which the transverse rib is rigidly connected to the main girder web, where (a) is a perspective view seen from obliquely below, and (b) is a side view. It is a perspective view of the principal part in FIG.10 (b). FIG. 13 is a plan sectional view of the main part in FIG. The same shows a shear force transmission member, (a) is a cross-sectional view of the main part showing a state where the shear force transmission member is attached, (b) is a perspective view of the shear force transmission member, and (c) is a shear force transmission. The front view of a member, (d) is a side view of a shear force transmission member, (e) is a bottom view of a shear force transmission member. (A) is a sectional view of the main part showing a steel slab and a reinforced concrete slab adjacent to it, (b) is a temporary paving with a temporary fixing plate between the steel slab and the reinforced concrete slab. It is sectional drawing of the principal part which shows the state which gave. It is sectional drawing which shows the principal part of the structure of the bridge concerning the 1st Embodiment of this invention. In the 1st Embodiment of this invention, it is for demonstrating the method of installing the next steel deck, and is the perspective view seen from diagonally upward which shows the state which provided the removal part. It is the perspective view seen from diagonally downward which shows the state which provided the removal part same. It is the perspective view seen from diagonally upward which shows the state which installed the next steel deck. It is the perspective view which showed the state which removed the reinforced concrete floor slab of the other side lane, and looked at the bridge from diagonally upward. FIG. 3 is a front sectional view showing a removed part of the reinforced concrete floor slab of the other lane. It is the perspective view which showed the state which installed the steel deck slab on the other lane side, and saw the bridge from diagonally upward. The state which installed the steel deck on the other lane side is the front sectional view in the said steel deck. FIG. 2 is a front sectional view showing a state in which a temporary fixing plate is temporarily installed between a steel slab and a reinforced concrete slab and temporarily paved. It is a front sectional view which shows the state which joined the steel deck adjacent to the bridge axis direction by the joint between panels similarly. It is a front sectional view which shows the state which joined the steel deck adjacent to a bridge axis orthogonal direction by the joint between panels similarly. It is the perspective view seen from diagonally downward which shows the state which installed the next steel deck. It is for demonstrating the bridge slab replacement | exchange method concerning the 2nd Embodiment of this invention, and is the perspective view which looked at the bridge before floor slab replacement from diagonally upward. However, only one lane is shown. It is the perspective view which looked at the bridge before a floor slab replacement from diagonally downward. FIG. 2 is a perspective view showing a state in which a part of a reinforced concrete slab is removed, and a bridge viewed obliquely from above. FIG. 3 is a perspective view showing a state in which a part of a reinforced concrete slab is removed, and a bridge viewed obliquely from below. FIG. 2 is a perspective view showing a state in which a steel deck is installed, and a bridge viewed obliquely from above. FIG. 2 is a perspective view showing a state in which a steel deck is installed, and a bridge viewed obliquely from below. FIG. 2 is a perspective view of a bridge viewed obliquely from above, showing a state in which a further part of the reinforced concrete slab is removed. FIG. 2 is a perspective view of a bridge viewed obliquely from below, showing a state in which a further part of the reinforced concrete slab is removed. FIG. 2 is a perspective view showing a state in which the next steel deck is installed, and a bridge viewed from obliquely above. FIG. 2 is a perspective view showing a state where a next steel deck is installed, and a bridge viewed from obliquely below. It is sectional drawing which shows the principal part of the floor slab replacement structure of a bridge. It is sectional drawing which shows the principal part of the bridge which concerns on the 3rd Embodiment of this 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, 2nd horizontal rib attachment member of the bridge from diagonally downward. It is sectional drawing which shows the principal part containing the residual concrete of a bridge same as the above. It is a figure which shows the analysis model of a bridge | bridging in case 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 analysis model of a bridge | bridging in case 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 sectional drawing which shows the principal part of the bridge which concerns on the modification of the 3rd Embodiment of this invention.

Embodiments of a bridge structure and a floor slab replacement method according to the present invention will be described below with reference to the drawings.
(First embodiment)
In the present embodiment, a case where a part of a reinforced concrete slab supported by a main girder of a bridge is replaced with a steel slab will be described in order according to the replacement construction steps.

In the first embodiment, the interval between main girders adjacent to each other in the bridge width direction is about 3 m, and a part of the reinforced concrete floor slab is cut in the bridge width direction and replaced with a new steel floor slab. This will be described with reference to the flowchart shown in FIG.
2A and 2B show the bridge before the floor slab replacement (however, only one lane (in the case of the figure, one lane in the case of one side)), FIG. 2A is a perspective view seen obliquely from 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, a counter tilting structure 13, and a reinforced concrete floor slab 14.
The main girder 11 is formed of H-shaped steel or I-shaped steel, and is provided to extend in the bridge axis direction (Z direction in FIG. 2A). In addition, in the case of what is shown in the figure, only six of the lanes on one side are shown out of a total of six main girders in both lanes. These main girders 11 are arranged at a predetermined interval 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 installed between an abutment and a pier (not shown).

  The cross beam 12 is formed of H-shaped steel or I-shaped steel, extends in the bridge width direction, and is spanned between the adjacent main beams 11, 11. The end of the cross beam 12 is welded to the main beam 11a. They are connected by bolting or the like. In addition, a plurality of cross beams 12 are arranged at a predetermined interval in the bridge axis direction. However, since a part of the bridge 10 is shown in FIG. 2B, two horizontal beams 12 extending coaxially in the bridge axis orthogonal direction are illustrated. A digit 12 is provided.

  The anti-tilt structure 13 is for resisting lateral loads such as wind and earthquake, and has a truss structure made of an upper chord material, a lower chord material, a vertical material, a diagonal material, and the like. The anti-tilt structure is installed between adjacent main girders 11 and 11, and is coupled to the main gird 11 by gussets or the like. In addition, a plurality of anti-tilt structures 13 are arranged at a predetermined interval in the bridge axis direction. However, since a part of the bridge 10 is illustrated in FIG. 2B, two anti-tilt structures extending coaxially in the direction orthogonal to the bridge axis are shown. 13 is provided, and the anti-tilt structure 13 is provided at a position spaced apart in the bridge axis direction and sandwiching the cross beam 12.

  The 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, protrusions (haunch portions) 14 a projecting from the lower surface extend in the bridge axis direction. In the present embodiment, three ridges 14a are formed at a predetermined interval in the bridge width direction. The three ridges 14a are positioned immediately above the three main girders 11, and are installed and fixed to the main girder upper flange 11b. A plurality of studs (not shown) are erected 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 coupled to the concrete of the reinforced concrete floor slab 14. Further, the reinforced concrete floor slab 14 is provided with a ground cover 14b at each end in the bridge width direction, and a rail 14c is provided at one end. Furthermore, on the upper surface of the reinforced concrete floor slab 14, a pavement 15 made of asphalt or the like is constructed between the ground covers 14b and 14b.

When a part of the reinforced concrete floor slab 14 laid and supported by the main girder 11 of the bridge 10 having such a configuration is replaced with a new steel floor slab, the bridge 10 is first prepared as a preparation process (step S1 in FIG. 1). Underneath, a full suspension scaffold (not shown) is installed, and members that interfere with the installation (replacement) of a new steel deck are removed, improved, and finished (partially grinder work). If a full-scale 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 attachment member 16 is bolted to the upper part of the main girder web 11a with a high-strength bolt. In this case, the work is performed on the lower surface side of the reinforced concrete slab 14 to bolt the lateral rib mounting member 16 to the main girder web 11a (step S2 in FIG. 1).
FIG. 3B is a cross-sectional view of the main girder 11 on the right side in FIG. In addition, the right side said below means the right side toward the display surface of this specification. The same applies to the left side.
As shown in FIG. 4, the lateral rib mounting member 16 is formed in a T-shaped cross section, and has a rectangular plate-like fixing plate 16 a and a central portion in the width direction of the fixing plate 16 a at a right angle from the plate surface of the fixing plate 16 a. And a rectangular plate-like connecting plate 16b protruding in the direction. The fixed plate 16a and the connecting plate 16b have the same length in the vertical direction, and the protruding length of the connecting plate 16b from the fixed plate 16a is the connecting plate 16b on the end surface of the lateral rib 33 of the steel deck 30 described later. It is set to such a length that the front end surface can be contacted. The horizontal rib attaching 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 tensile bolt joining. They are connected by friction welding of two-surface shear.
The fixing plate 16a is provided with a plurality of bolt holes 16c, and the connecting plate 16b is provided with a plurality of bolt holes 16d.

  Such a lateral rib attaching member 16 is attached by bringing the fixing plate 16a into contact with the web surface of the main girder web 11a located below the site where the newly installed steel deck is to be replaced and bolting. In this embodiment, since a part of the reinforced concrete floor slab 14 is replaced with a steel floor slab between the right main girder 11 and the central main girder 11 in FIG. 3 (a), as shown in FIG. The lateral rib attachment members 16 are attached to both web surfaces of the main girder web 11a of the right main girder 11 substantially symmetrically with the central part in the thickness direction of the main girder web 11a as a boundary. The horizontal rib attachment member 16 is attached to 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 is longer in the vertical direction than the left lateral rib mounting member 16, and the lower end of the right lateral rib mounting member 16 is the left lateral rib mounting member. 16 protrudes downward from the lower end of 16. This is because the vertical length of the end of the lateral rib 33A on the main girder web 11a side which will be described later is longer than the vertical length of the end of the lateral rib 33B on the main girder web 11a side, and the horizontal rib 33A. This is because the lower end of the projection protrudes downward from the lower end of the lateral rib 33B (see FIG. 10B). Accordingly, when the length in the vertical direction of the end portion of the horizontal rib 33A on the main girder web 11a side is equal to the length in the vertical direction of the end portion of the horizontal rib 33B on the main girder web 11a side, the right horizontal rib attachment member 16 is provided. The length in the vertical direction may be equal to the length in the vertical direction of the left lateral rib attachment member 16.

In addition, when the lateral rib attachment member 16 is coupled to the web surface of the right main girder web 11a, the coating on the web surface is peeled off and then coupled by normal friction welding using a high-strength bolt. 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 is in contact with both the web surfaces of the bolt hole 11d and the main girder web 11a. The high-strength bolt 18 is inserted into the bolt holes 16c, 16c of the fixing plate 16a of the lateral rib attaching members 16, 16, and the nut 18a is screwed into the high-strength bolt 18 and tightened to tighten the web of the main girder web 11a. The lateral rib attachment member 16 is coupled to the surface.
At this time, the fixing plate 16a of the horizontal rib mounting member 16 is previously drilled at the factory and is provided with bolt holes 16c, while the main girder web 11a is in the stage before the coupling operation is performed. The bolt hole 11d is not provided. The horizontal rib attachment member 16 is temporarily installed at an appropriate position, and the bolt hole 16c is used as a template to drill a hole in the main girder web 11a using a tool such as a portable drilling machine not shown in the field. At the time of the coupling work, there is a possibility that positional displacement may occur between the members, and it is necessary to adjust the position of the bolt hole. Position adjustment is possible.
The same applies to the case where the lateral rib attaching member 16 is coupled to the web surface of the central main girder web 11a.
In addition, a reinforced concrete slab laid on the web surface on the opposite side (left main girder 11 side) of the central main girder web 11a is supported by the central main girder 11 and the left main girder 11. When a part of 14 is replaced with a new steel slab, the horizontal rib attaching member 16 is attached in the same manner.
In addition, after attaching the horizontal rib attachment member 16 to the main girder 11, as shown in FIG. 6, lane control of upper traffic is performed as needed (step S3 of FIG. 1). When lane regulation is performed, temporary guards 17 are erected at predetermined intervals in the bridge axis direction at the center in the width direction (bridge width direction) of the road surface. FIG. 6 shows the one lane restricted on the right side, with the left side of the temporary guard 17 being a vehicle lane and the right side being 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 portion 20 is provided in a part of the reinforced concrete floor slab 14, and the remaining reinforced concrete 21 is left on the upper surface side of the main girder upper flange 11b in the removal portion 20 (reinforced concrete floor slab removal step).

That is, as shown in FIG. 6 and FIG. 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 is defined. According to the plan view shape and size of the steel slab described later (in the case of this embodiment, a substantially rectangular shape in plan view), it is cut with a concrete cutter and removed (step S4 in FIG. 1). At this time, the removal portion 20 is provided at a predetermined portion (a part) of the reinforced concrete floor slab 14 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. In this case, the remaining 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 the upper half of the upper surface of the main girder upper flange 11b of the central main girder 11 (half in the bridge width direction). Reinforced concrete 21 is left.
At this time, in the peripheral portion surrounding the removal portion 20 of the reinforced concrete floor slab 14, the portion of the reinforced concrete floor slab 14 adjacent to the removal portion 20 in the bridge width direction is on the upper surface side of the main girder upper flange 11 b of the main girder 11. Then, a part of the pavement portion 15 is removed along the bridge axis direction, and the edge portion along the removal portion 20 is exposed. Further, for the portion of the reinforced concrete floor slab 14 that is located between the main girders 11 and adjacent to the removal portion 20 in the bridge axis direction, the pavement portion 15 is removed along the bridge width direction, and a pair along the removal portion 20. Expose the edges.

  In this way, the length in the bridge axis direction in plan view of the rectangular removal portion 20 formed by cutting a predetermined portion of the reinforced concrete deck 14 into a substantially rectangular shape in plan view is a newly installed steel deck that can be replaced. It is set slightly longer than the length in the bridge axis direction in plan view. Further, when cutting a predetermined portion of the reinforced concrete floor slab 14 into a substantially rectangular shape in plan view, since the right side cover 14b and the rail 14c are cut, the outer side (right side) of the removal portion 20 in the bridge width direction is opened. Yes.

  Further, in such a reinforced concrete floor slab removing process, as shown in FIG. 8, the cover 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 thereof are hammered. It is removed by manual work such as hitting (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. To do.

Next, as shown to Fig.9 (a), it arrange | positions to the said removal part 20 so that the newly installed steel deck 30 may be covered on the remaining reinforced concrete 21, and is temporarily set | placed (steel deck installation process). . In this case, the remaining reinforced concrete 21 is arranged so as to be sandwiched between lower extending vertical ribs 32A and 32A described later in the bridge width direction, and the bottom surface of the deck plate 31 is brought into contact with the upper surface of the remaining reinforced concrete 21, thereby providing a steel floor. The plate 30 is temporarily placed (step S6 in FIG. 1).
As shown in FIG. 10, the steel deck 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 previously constructed on the upper surface of the deck plate 31. The outer peripheral edge 31 a of the deck plate 31 protrudes outward from the outer peripheral edge of the pavement 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. 10 (b), FIG. 11, and FIG. 17, two vertical ribs 32 arranged so as to sandwich the main girder upper flange 11b in the bridge width direction among the plurality of vertical ribs 32 are other vertical ribs. 32, and the lower end of the deck plate 31 of the newly installed steel deck 30 is in contact with the upper surface of the remaining reinforced concrete 21, and the lower end extends sufficiently below the lower surface of the main girder upper flange 11b. The lower extending vertical ribs (ribs) 32A and 32A are provided. The lower extending vertical ribs 32 </ b> A and 32 </ b> A act as mechanical ribs as vertical ribs of the steel deck 30, and as a part of the web of the main girder 11 through the shear force transmission member 50 and the steel deck 30. It has an action of transmitting a shearing force in the bridge axial direction between the main girders 11. Moreover, as another function, it functions as a part of formwork in covering the circumference | surroundings of the remaining reinforced concrete 21 and filling the amorphous material 47 mentioned later between the steel floor slabs 30. FIG.
When the newly installed steel floor slab 30 is placed on the remaining reinforced concrete 21 on the removal portion 20 having a rectangular shape in plan view, the lower extending vertical ribs 32A and 32A are the upper main girder flanges of the right main girder 11. 11b is arranged so as to be sandwiched 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 downwardly extending vertical ribs 32A and 32A facing the end in the bridge width direction. The sealing material 36 is fitted into the gap. Also, a concrete mold, a titanium foil for waterproofing and corrosion prevention, extends 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. 37 is pasted.

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

Next, the horizontal rib 33 of the steel deck 30 is rigidly coupled to the main girder web 11a closest to the end at the end of the horizontal rib 33 in the bridge width direction (lateral rib rigid coupling step) (FIG. 1). Step S8).
As shown in FIG. 10, the steel deck 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 nearest main girder 11. It has a transverse rib 33 that faces the web surface of the main girder web 11a.
Specifically, two lateral 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 interposed therebetween.

  Moreover, as shown in FIG. 12, the horizontal rib 33A on the right side in the bridge width direction in the steel deck 30 of the present embodiment has a lower end formed in a substantially horizontal direction from the main girder 11 to a certain distance, and further the main girder. At a position away from the main girder 11, the lower end portion is formed in a plate shape 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 (that is, the end surface on the main girder side) of the transverse rib 33A in the bridge width direction 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 inclined (inclined with respect to the horizontal plane). Such horizontal ribs 33A are arranged at substantially the center of the short side length direction (bridge axis direction) of the deck plate 31, and the vertical ribs 32 are arranged orthogonally to the horizontal ribs 33A. The intersection is welded. Further, the surface of the lower extending vertical rib 32A opposite to the main girder upper flange 11b faces the 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 In addition to being in contact with one end surface 33a of the horizontal rib 33A so as to be orthogonal to the extending direction, the horizontal rib 33A is joined to the horizontal 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 downward from the lower surface of the main girder upper flange 11b, and the surface on the most recent main girder 11 side is the main girder web 11a. It is in a state of facing the web surface.

  Moreover, as shown in FIG.10 (b), FIG.13, and FIG.17, the horizontal rib 33B of the bridge width direction left side of the steel deck 30 is on the base part formed in the rectangular plate shape, and the both ends of a bridge width direction. It is formed in the shape of a plate having a protrusion 33c that is provided and protrudes downward from the base. The projecting portion 33c is formed in a plate shape whose lower end side gradually projects downward as it goes to both end sides in the extending direction of the lateral rib 33B. Therefore, both ends of the lateral rib 33B and the vicinity thereof have a shape in which the length in the vertical direction becomes larger as going to both ends in the extending direction due to the protruding portion 33c. Further, both end surfaces of the lateral rib 33B are opposed to the web surfaces of the nearest main girder web 11a. That is, the substantially lower half of one end surface (left end surface) 33d of the horizontal rib 33B is opposed to the web surface of the main beam 11a of the main girder 11 at the central portion, and the other end surface (right end surface) 33d of the horizontal rib 33B. The 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 arranged at a substantially central portion in the length direction of the short side of the deck plate 31, that is, is arranged on an extension of the horizontal rib 33A, and the vertical rib 32 is arranged orthogonal to the horizontal rib 33B. And their intersections are welded.

Then, the width of the lateral ribs 33A and 33B is set so that one end face of each of the lateral ribs 33A and 33B in the bridge width direction faces the web surface of the main girder web 11a. The direction end portions 33e and 33e are rigidly connected to the nearest main girder webs 11a and 11a. Thereby, the generated stress resulting from the traffic load accompanying the floor slab action of the steel floor slab 30 can be reduced. That is, even if the horizontal ribs 33 have the same height, the stress generated in the steel deck 30 is reduced by rigidly coupling to the main girder webs 11a, 11a, and a sufficient fatigue life can be secured.
Specifically, in the present embodiment, with respect to the lateral rib 33B, as shown in FIG. 14, the one end surface 33d of the end portion 33e in the bridge width direction is opposed to the web surface of the main girder web 11a. Further, the end 33e and the connecting plate 16b are spliced from both sides thereof after being brought into contact with the front end surface of the connecting plate 16b of the lateral rib mounting member 16 fixed to the main girder web 11a of the main girder 11 at the center. The plate is sandwiched between the plates 42 and 42 and is friction-joined by the high-strength bolt 45 and the nut 45a. Thereby, the horizontal rib 33B is rigidly coupled to the main girder web 11a closest to the end 33e at the left end 33e of the horizontal rib 33B in the bridge width direction. By adopting such a structure, as will be described later, it becomes possible to easily adjust the position of the entire steel deck (particularly the deck plate) in the vertical direction on site. In the case of the structure of Patent Document 1, a horizontal rib is placed on the bracket. However, 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 takes time and fine adjustment is extremely difficult. On the contrary, it is impossible to adjust downward.
Similarly, the splice plate is connected to the distal end portion of the connecting plate 16b of the horizontal rib mounting member 16 with the right end 33e of the horizontal rib 33B in the bridge width direction 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 used for rigid coupling.

  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 the splice plate 42 is also formed in advance in a factory or the like as shown in FIGS. 42c is formed. Then, using the bolt hole 42c of the splice plate 42 as a template, a hole such as a portable drilling machine (not shown) is drilled to form a bolt hole 33g at the end 33e in the bridge width direction of the lateral rib 33B. To do. Or the bolt hole 33g can also be formed in the edge part 33e of the bridge width direction of the horizontal rib 33B with the multiple drilling tool which is not shown in figure. That is, multiple holes having a number corresponding to the number of bolt holes 42c in the plurality of bolt holes 42c formed in the splice plate 42 in contact with the surface of the end portion 33e in the bridge width direction of the lateral rib 33B. A bolt hole 33g is formed in the end portion 33e while inserting the opening tool. As a result, the working time can be greatly reduced as compared with a normal single portable drilling machine. In addition, there is a possibility that positional displacement may occur between the members at the time of coupling work, and the position of the bolt holes may have to be adjusted. With this method, the bolt holes between the splice plate 42 and the lateral rib 33B can be adjusted. Relative position adjustment can be easily performed.

  Then, after inserting the high-strength bolt 45 into the bolt holes 42c, 16d, 42c and the bolt holes 42c, 33g, 42c arranged coaxially, the nut 45a is screwed into the high-strength bolt 45 and tightened. Thus, at the end 33e in the bridge width direction of the horizontal rib 33B, the end 33e is rigidly coupled to the nearest main girder web 11a by friction bonding. In FIGS. 12 and 13, the high-strength bolt 45 is not shown.

  Further, in such a friction joining structure using high-strength bolts, the surface of 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 connecting plate 16b is joined. In order to stably secure a friction coefficient necessary for friction bonding on the surface, a friction surface treatment by metal spraying of aluminum or the like is performed 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 the low-strength metal aluminum is sprayed in a molten state to form an aluminum sprayed layer. ing. In the ground treatment, for example, blasting is performed so that the surface roughness (maximum height Rz) is 50 μm or more.

The aluminum sprayed layer (metal sprayed layer) is formed in the circumference on the joint surface around the bolt hole 42c through which the high-strength bolt 45 is inserted. The diameter of this circumference is set to about three times the shaft diameter of the high strength bolt 45, for example. Moreover, 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 way, it is possible to secure a friction coefficient necessary for friction joining and minimize the number of high-strength bolts 45.

Similarly, as shown in FIG. 12, with respect to the lateral rib 33A, the right main girder in the state where one end surface 33d of the one end portion 33e in the bridge width direction is opposed to the web surface of the main girder web 11a. 11 abuts against the end face of the connecting plate 16b of the lateral rib mounting member 16 fixed to the main girder web 11a, and sandwiches the end portion 33e and the connecting plate 16b with the splice plates 42, 42 from both sides, By fastening with the high-strength bolt 45, the lateral rib 33B is rigidly coupled to the main girder web 11a closest to the end 33e at the end 33e of the lateral rib 33A.
Also in such a friction joining structure using high-strength bolts, the surface of the splice plate 42 to which the surface of the end portion 33e of the lateral rib 33A in the bridge width direction is joined and the splice plate 42 to which the surface of the connecting plate 16b is joined. The surface of the surface is subjected to a friction surface treatment by metal spraying of aluminum or the like by a factory or the like. Further, using the bolt hole 42c of the splice plate 42 as a template, drilling is performed using a tool such as a portable drilling machine (not shown) or multiple drilling tools, and the end portion of the lateral rib 33A in the bridge width direction is formed. The bolt hole 33g may be formed in 33e as in the case of the connection between the splice plate 42 and the lateral rib 33B described above.

  Next, as shown in FIG. 11 (b), an amorphous 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 the height adjustment bolt 40 is removed from the screw hole 41, the space between the lower extending vertical ribs 32A and 32A in which the main girder upper flange 11b and the remaining reinforced concrete 21 are accommodated is received from the screw hole 41. The amorphous material 47 is filled (step S9 in FIG. 1). As described above, the lower extending vertical ribs 32A and 32A are disposed so as to sandwich the main girder upper flange 11b in the bridge width direction, and the gap between the main girder upper flange 11b and the lower extending vertical ribs 32A and 32A is disposed. Since the sealing material 36 is fitted, the unshaped material 47 filled from the screw hole 41 includes the deck plate 31 of the steel floor slab 30, the main girder upper flange 11b, the sealing material 36, and the downwardly extending vertical rib. The space surrounded by 32A and 32A is spread without gaps to fill the gaps. Thereby, corrosion of the upper reinforcement 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 amorphous material 47, for example, mortar is used, but other than that, a material having rapid curability and fluidity such as non-shrinkable resin, rubber latex and the like can be used.
In addition, you may perform the filling operation | work of such an indefinite shape material 47 after the steel deck joining process by the shearing force transmission member 50 mentioned later. Moreover, you may pack collectively after the construction of the steel deck 30 of several panels for the whole work efficiency improvement. This is because the dead load and live load (traffic load) acting on the steel deck 30 are transmitted to the main girder web 11a through the lateral ribs 33 in terms of design.

Next, as shown in FIGS. 10, 12, and 15, the main girder 11 and the steel deck 30 are coupled by a shear force transmission member 50 that transmits a shearing force in the bridge axis direction (steel deck coupling process). (Step S10 in FIG. 1).
The shearing force transmitting member 50 transmits the shearing force in the bridge axis direction between the main girder 11 and the steel deck 30 and is formed by bending a steel plate made of, for example, a rectangular SBHS steel material, The first fixed plate 50a, the second fixed plate 50b, and the connecting plate 50c are integrally provided. Further, the first fixing plate 50a and the second fixing plate 50b are provided with bolt holes 50d through which bolts 51 and 52, which will be described later, can be inserted, spaced apart in the bridge axis direction.
The shear force transmission member 50 may be formed of SUS or cast iron, for example, other than SBHS steel. In the present embodiment, the shear force transmitting member 50 is formed in a crank shape (substantially Z-shaped), but the shear force can be transmitted between the main girder 11 and the steel deck 30 in the bridge axis direction. If they can be combined, they may have different shapes as required for design and construction. Since the shearing force transmitting member 50 is responsible for transmitting the shearing force, it is only necessary to ensure a necessary cross-sectional area in terms of 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) extend in the vertical direction and the bridge axis direction. The first fixing plate 50a and the second fixing plate 50b have the same long side and short side, and are separated in parallel to the bridge axis orthogonal direction (bridge width direction). Although the lengths of the short sides of the first fixing plate 50a and the second fixing plate 50b may be different, it is preferable that the lengths of the long sides are equal.

The connecting plate 50c connects the first fixed plate 50a and the second fixed plate 50b, is formed in a rectangular plate shape that is long in the bridge axis direction, and the plate surface (surface) spreads in the horizontal direction. ing. The connecting plate 50c has a long side length equal to the long side lengths of the first fixing plate 50a and the second fixing plate 50b, and one long side portion of the connecting plate 50c is the first fixing plate 50a. The other long side portion of the connecting plate 50c is connected to the upper long side portion of the second fixed plate 50b. Further, the length of the short side of the connecting plate 50c is substantially equal to the horizontal distance from the edge in the width direction of the main girder upper flange 11b to the web surface of the main girder web 11a.
The length of the shear force transmission member 50 in the bridge axis direction is appropriately determined. If the total cross-sectional area of the shear resistance cross section in the shear force transmitting member 50 has the same cross-sectional area as the main girder web 11a, the shear force can be exchanged between the steel deck 30 and the main girder 11, and the result As a result, the steel slab 30 and the main girder 11 can be synthesized to behave integrally.

The shearing force transmitting member 50 having such a configuration is such that the connecting plate 50c is horizontally oriented on the lower side of the steel deck 30 and the first fixing plate 50a and the second fixing plate 50b protrude vertically from the connecting plate 50c. Arrange in a state. And after making the 1st fixing plate 50a of the shearing force transmission member 50 contact | abut to the downward extending vertical rib 32A of the steel deck 30, as shown in FIG. 15, it is high force to the said downward extending vertical rib 32A. After the second fixing plate 50b is brought into contact with the main girder web 11a by the bolt 51, it is coupled to the main girder web 11a by the bolt 52. The connecting plate 50c of the shear force transmitting member 50 is disposed on the lower surface side of the main girder upper flange 11b in a state of being separated from the main girder upper flange 11b. In this way, the main girder 11 and the steel deck 30 are coupled by the shear force transmission 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 32 </ b> A on the right side (displacement side) and the first fixing plate 50 a of the shearing force transmission member 50 on the right side (displacement side). 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 carried into the site by making bolt holes 50 d for the bolts 51 and 52 in advance. In the field, using these bolt holes 50d provided in the shearing force transmission member 50 as templates, the main girder web 11a and the downwardly extending vertical rib 32A are drilled using a tool such as a portable drilling machine (not shown). Thereby, the adjustment function of the dimension error of an up-down direction is securable on the spot.
Further, a plurality of shear force transmission members 50 may be provided at predetermined intervals along the bridge axis direction, and the main girder 11 and the steel deck 30 may be coupled by the plurality of shear force transmission members 50, or one shear force The main beam 11 and the steel deck 30 may be coupled by the transmission member 50. For shear force transmission, the total cross-sectional area of the shear resistance cross section of the shear force transmission member 50 has an effect. Therefore, if a sufficient shear resistance cross section can be ensured for the entire shear transmission member, the steel can be divided even if the shear transmission member is divided. There is no difference in the synthesis effect of the floor slab 30 and the main girder 11. However, it is preferable that two or more bolts 51 and 52 are respectively disposed on at least one shear force transmission member 50 so that the shear force transmission member 50 does not cause a rotational motion.

In the present embodiment, as shown in FIG. 12, the shear force transmission members 50 are arranged at positions where the horizontal ribs 33 of the steel deck 30 are sandwiched in the bridge axis direction, and the main girder 11 is formed by these shear force transmission members 50. And the steel slab 30 are combined.
Further, as shown in FIG. 15, the shear force transmission member 50 is symmetrically arranged in the bridge width direction with the main girder web 11a of the right main girder 11 interposed therebetween, and one shear force transmission member 50 is placed under the one. The extending vertical rib 32A and one web surface of the main girder web 11a are coupled by a bolt 52, and the other shearing 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.

In this way, by connecting the main girder 11 and the steel deck 30 with the shearing force transmitting member 50 that transmits the shearing force in the bridge axis direction to each other, the bridge shaft from the main girder 11 toward the steel deck 30 is obtained. Can transmit shear force in the direction.
Further, by providing the net member 62 at the end opening in the bridge axis direction of the portion surrounded by the shear force transmission member 50 and the main girder upper flange 11b, a bird such as a pigeon enters the surrounded portion. Can be prevented.
At this time, as shown in FIG. 15, by interposing the liner plate 61 between the second fixing plate 50b of the left side (shift side) shearing force transmitting member 50 and the main girder web 11a, the main girder 11 is interposed. The dimensional error in the bridge width direction of the steel deck 30 may be absorbed.
Moreover, such a steel floor slab joining process by the shear force transmission member 50 may be performed after a paving process described later, or may be performed simultaneously with the paving process. That is, since the main girder 11 and the steel deck 30 are synthesized by the installation of the shear force transmitting member 50, the generated stress in the main girder 11 is greatly reduced, but the generated stress before the installation of the shear force transmitting member 50 is reduced. Even in a high state, if it is within the upper limit of design stress of the steel material forming the main girder 11 or the steel deck 30, it is possible to bear a traffic load in a short time. Therefore, after the pavement process, it is also possible to perform the installation work of the shearing force transmission member 50 while allowing traffic on the steel slab.

Next, as shown in FIG. 9B and FIG. 16, the temporary fixing plate 55 is provided between the steel deck 30 and the reinforced concrete deck 14 adjacent to the steel deck 30 in the bridge width direction and the bridge axis direction. The temporary paving portion 56 is constructed on the upper surface side of the temporary fixing plate 55 so as to be substantially flush with the paving portion 34 provided in advance on the upper surface of the steel floor slab 30 and the paving portion 15 on the reinforced concrete floor slab 14. (Step S11 in FIG. 1). The temporary fastening plate 55 temporarily suppresses the depressed state of the road and allows the vehicle to pass by continuously connecting between the reinforced concrete floor slab 14 and the steel floor slab 30 or between adjacent steel slabs. It has a function.
That is, as shown in FIG. 16 (a), in the bridge width direction in the peripheral portion of the reinforced concrete floor slab 14 surrounding the removal portion 20 where the steel floor slab 30 is disposed by the above-described reinforced concrete floor slab removal step. In the adjacent part, a part of the pavement 15 is removed on the upper surface side of the main girder upper flange 11b of the main girder 11, and the edge adjacent to the removed part 20 in the bridge width direction of the reinforced concrete floor slab 14 is exposed. It has become. Further, a portion of the reinforced concrete floor slab 14 located between the main girders 11 and 11 and adjacent to the bridge axis direction is partially removed along the bridge width direction so that the bridge shaft of the reinforced concrete floor 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 protrudes outward from the outer peripheral edge of the pavement 34, and a plurality of bolt holes 31b are provided in the protruding outer peripheral edge 31a.
Further, in the bridge width direction and the bridge axis direction, there is a gap S between the outer peripheral edge portion 31a of the steel deck 30 and the edge portion (outer peripheral edge portion 32a) along the bridge axis direction and the bridge width direction of the reinforced concrete floor slab 14. Is provided.

  Then, as shown in FIG. 16 (b), the temporary fixing plate 55 is placed so as to straddle the gap S between the outer peripheral edge portion 31 a of the deck plate 31 and the edge portion 32 a along the bridge axis direction of the reinforced concrete floor slab 14. Cross 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 tightened with the nut 57a to fix the temporary fixing plate 55, and then the temporary paving portion 56 is placed on the upper surface side of the temporary fixing plate 55. The pavement part 34 provided in advance on the upper surface 30 and the pavement part 15 on the reinforced concrete floor slab 14 are applied approximately flush with each other. FIG. 16 shows a case where the temporary paving portion 56 is provided by bridging the temporary fixing plate 55 in the gap S between the outer peripheral edge portion 31a of the deck plate 31 and the edge portion 32a along the bridge axis direction of the reinforced concrete floor slab 14. However, even when the temporary paving portion 56 is provided by bridging the temporary fixing plate 55 in the gap S between the outer peripheral edge portion 31a of the deck plate 31 and the edge portion 32a along the bridge width direction of the reinforced concrete floor slab 14, The same procedure is used.

  The bridge floor slab replacement structure thus constructed 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 that has been removed by removing portions other than the portion and at least a part of the reinforced concrete floor slab 14 are removed to the removed reinforced concrete 21 by removing the remaining reinforced concrete 21 in an exposed state (see FIG. 6). And a steel slab 30 disposed so as to be covered.

The steel deck 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 web surface of the main girder web 11 a of the main girder 11. The lateral rib 33 (33A, 33B) is opposed to the main girder web 11a closest to the end 33e by the lateral rib mounting member 16 at the end 33e of the lateral rib 33. It is rigidly connected.
Moreover, as shown in FIG. 12, the main girder 11 and the steel deck 30 are couple | bonded by the shear force transmission member 50 which transmits a shear force to a bridge axis direction.

  Further, an amorphous material 47 is filled between the steel deck 30, the main girder upper flange 11 b and the remaining reinforced concrete 21. Further, a temporary fixing plate 55 is bridged between the steel floor slab 30 and the reinforced concrete floor slab 14 adjacent to the steel floor slab 30, and the temporary paving portion 56 is provided on the upper surface side of the temporary fixing plate 55. 30 pavement portions 34 and the pavement portion 15 on the reinforced concrete floor slab 14 are substantially flush with each other.

In this way, after the replacement of one steel deck 30 is completed, the temporary traffic restriction is canceled and the construction zone can be passed (step S12 in FIG. 1).
When the second steel deck 30 is replaced, the above steps are basically repeated in sequence. However, detailed description of each process is omitted.
First, as shown in FIG. 18 and FIG. 19, in the construction zone, a part of the reinforced concrete floor slab 14 adjacent to the steel floor slab 30 that has been replaced (newly installed) in the bridge axis direction is the bridge axis direction (Z The removal portion 20 is provided in a part of the reinforced concrete floor slab 14 by removing portions other than the portion provided on the upper surface side of the main girder upper flange 11b within a predetermined width in the direction). The remaining reinforced concrete 21 is left on the upper surface side of the girder flange 11b (reinforced concrete floor slab removing step). Further, the lateral rib attaching member 16 is bolted to the upper portion of the main girder web 11a with a high strength bolt.

Next, as shown in FIGS. 20A and 21, the removal plate 20 is disposed so that the next steel deck 30 is placed on the remaining reinforced concrete 21 (see FIG. 9), and the height adjusting bolt 40 (FIG. 11) to adjust the height of the steel deck 30 (steel deck layout step).
Next, the horizontal rib 33 of the steel deck 30 is rigidly coupled to the main girder web 11a closest to the end at the end of the horizontal rib 33 by the horizontal rib attachment member 16 (lateral rib rigid coupling step).
Further, at this stage, as shown in FIGS. 20G and 20H, the adjacent steel floor slabs 30 and 30 are joined to each other by the high-strength bolt 46 using the inter-panel joint 35. This inter-panel joint 35 integrates adjacent steel decks 30 and 30 by bolt friction welding of two-surface shear. By this inter-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 deck 30, the vertical rib 32, and the downwardly extending vertical rib 32A (see FIG. 20G). ) Are joined by two-surface shear bolt friction joining. When the inter-panel joint 35 is provided, if there is a temporary fixing plate 55 that exists in advance, the temporary fixing plate 55 is removed.

Further, as shown in FIG. 20G, the inter-panel joint 35 for joining the steel decks 30 and 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. The joint plate 35a extending in the long side direction (bridge axis orthogonal direction) of the steel deck 30, the longitudinal ribs 32 between the longitudinal ribs 32, 32 adjacent to each other in the bridge axis orthogonal direction on the lower surface side of the deck plate 31, and A plurality of joint plates 35b shorter than the joint plates 35a are provided between the lower extending vertical ribs 32A. Then, the deck plates 31 and 31 of the adjacent steel floor slabs 30 and 30 are sandwiched by the joint plate 35a and the joint plate 35b and fastened by the high strength bolt 46, so that the steel floor slabs 30 and 30 are joined to each other. Has been.
Further, the inter-panel joint 35 that joins the vertical ribs 32, 32 of the steel decks 30, 30 adjacent to each other in the bridge axis direction and the lower 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 decks 30 and 30 adjacent to each other in the bridge axis direction. The vertical ribs 32 and 32 and the downwardly extending vertical ribs 32A and 32A of the steel decks 30 and 30 adjacent to each other in the bridge axis direction are sandwiched by the joint plates 35c and 35c, respectively, and fastened by the high strength bolt 46. Thus, the steel decks 30 and 30 are joined together.

Further, as shown in FIG. 20H, the inter-panel joint 35 that joins the steel floor slabs 30 and 30 adjacent to each other in the bridge axis orthogonal direction (left and right direction in FIG. 20H) includes two joint plates 35d and 35d. Yes. The joint plate 35d is arranged so as to straddle the joint portion between the steel decks 30 and 30 adjacent to each other in the direction orthogonal to the bridge axis, and along the short side direction of the steel deck 30 (direction orthogonal to the paper surface in FIG. 20H). It is extended. The deck plates 31 and 31 of the steel decks 30 and 30 adjacent to each other in the bridge axis orthogonal method are sandwiched by the joint plates 35d and 35d, respectively, and fastened by the high-strength bolts 46. The two are joined.
Next, the main girder 11 and the steel deck 30 are coupled by the shear force transmitting member 50 that transmits the shearing force in the bridge axis direction (steel deck coupling process).
In addition, before this steel deck connection process, an amorphous material is filled between the steel deck 30, the main girder upper flange 11 b, and the remaining reinforced concrete 21.

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

  After the next (second) steel slab 30 is replaced in this way, the necessary number of steel slabs 30 are replaced one after another in the same manner, so that the reinforced concrete floor slab 14 is displaced by a desired distance in the direction of the bridge axis. Instead, a new steel deck 30 is installed. As described above, a new steel deck 30 is newly provided for a desired distance in the bridge axis direction with respect to one of the two lanes on one side.

In addition, after a new steel floor slab 30 is newly installed in place of the reinforced concrete floor slab 14 for a desired distance in the bridge axis direction with respect to one lane, as shown in FIG. 20B, the other lane of the two lanes on one side is shown. Similarly, a new steel slab 30 is newly installed in place of the existing reinforced concrete slab 14 (left lane in FIG. 20B).
In FIG. 20B, two steel decks 30 replaced in one lane are shown, but in actuality, a predetermined number of steel decks 30 are continuously constructed (newly installed) in the bridge axis direction.
In addition, when the steel deck 30 is newly installed in the other lane, the steel deck 30 is newly installed in the same manner as when the steel deck 30 is newly installed in the one lane. To explain.

When a new steel floor slab 30 is newly installed in the lane on the other side of the two lanes on one side, instead of the reinforced concrete floor slab 14, as a preparatory step, after installing the entire scaffold and removing the interfering members, the reinforced concrete On the lower surface side of the floor slab 14, an operation of bolting the lateral rib mounting member 16 to the upper portion of the main girder web 11a of the predetermined main girder 11 with a high strength bolt is performed.
Then, after restricting the upper traffic for the other lane (not shown), as shown in FIG. 20B and FIG. 20C, the main girder 11 of at least part of the reinforced concrete floor slab 14 of the other lane is shown. By removing the portion 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. The remaining reinforced concrete 21 is left (reinforced concrete floor slab removal process).
Next, as shown to FIG. 20D and FIG. 20E, it arrange | positions so that the steel deck 30 may be covered on the remaining reinforced concrete 21 in the removal part 20 (steel deck installation process). Next, as shown in FIG. 20E, the lateral ribs 33 are rigidly coupled to the main girder web 11a closest to the both ends by the lateral rib mounting members 16 at both ends in the bridge width direction of the lateral ribs 33 (lateral ribs). Rigid coupling process). In addition, the lateral rib attaching member 16 is bolted to the main girder web 11a in advance. When the lateral rib 33 is bolted to the lateral rib mounting member 16, the lateral rib mounting member 16 and the end of the lateral rib 33 are sandwiched by the splice plate 42 and fastened by a high strength bolt.
Next, the main girder 11 and the steel deck 30 are coupled by the shear force transmitting member 50 that transmits the shearing force in the bridge axis direction (steel deck coupling process).

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

In the lane on the other side as well, the covering concrete above the remaining reinforced concrete 21 is removed in the reinforced concrete floor slab removing step.
Further, a height adjusting bolt capable of adjusting the height of the steel floor slab 30 is screwed onto the steel slab 30 so as to come into contact with the remaining reinforced concrete 21, and the height adjustment is performed after the steel floor slab arranging step. Adjust the height of the steel deck by turning the bolt.
Further, after the steel deck slab disposing step, an amorphous material is filled between the steel deck 30, the main girder upper flange 11 b, and the remaining reinforced concrete 21.

As described above, according to the present embodiment, the steel deck 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 main main surface. The transverse rib 33 (33A, 33B) facing the web surface of the main girder web 11a of the girder 11 is provided, and the transverse rib 33 is rigid at the end of the transverse rib 33 to the main girder web 11a closest to the end. Are combined. That is, unlike the conventional case, the ends of the horizontal ribs 33 of the steel deck 30 are rigidly coupled directly to the main girder web 11a without using the floor support bracket, so that the steel deck 30 and the main girder 11 are integrated. As a bridge of structure, it can ensure the rigidity as a bridge, and the trouble of attaching the floor slab support bracket to the main girder web 11a and the trouble of attaching the horizontal rib of the steel slab to the floor slab support bracket Can be reduced.
Further, since the main girder 11 and the steel deck slab 30 are coupled by a shearing force transmission member 50 that transmits a shearing force in the bridge axis direction, the main girder 11 and the steel deck 30 are sheared in the bridge axis direction. Power can be transmitted reliably.
If the horizontal rib 33 is rigidly coupled to the main girder web 11a, the vertical position of the horizontal rib 33 during construction can be easily adjusted in the case of the rear hole type. Of course, if it is known that the position adjustment of the horizontal ribs 33 during construction is small, it is possible to reduce the construction time and labor at the construction site by forming a hole in the factory as a pre-hole method. You can also.

Moreover, since it is only necessary to remove the covering concrete 22 on the upper part of the remaining reinforced concrete 21, it is not necessary to remove the concrete between the studs standing on the main girder upper flange 11b. Since the concrete between the studs requires much labor to remove, leaving the concrete can greatly reduce the labor of the removal work.
Moreover, since the remaining 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.
Furthermore, since the height of the steel deck 30 can be adjusted by turning the height adjusting bolt 40, the height of the steel deck 30 is changed to that of the reinforced concrete deck 14 that has not been replaced or the steel deck 30 previously installed. Can be equal to height. That is, the planned road surface height can be adjusted at the site.

Moreover, since the amorphous material 47 is filled between the steel deck 30, the main girder upper flange 11 b, and the remaining reinforced concrete 21, the bottom surface of the steel slab 30 exposed between the reinforcing bars of the remaining reinforced concrete 21 and the space (space). Corrosion of the upper surface of the main girder upper flange 11b can be prevented.
Further, a temporary fixing plate 55 is bridged between the steel floor slab 30 and the reinforced concrete floor slab 14 adjacent to the steel floor slab 30, and a temporary pavement portion 56 is provided on the upper surface side of the temporary fixing plate 55. Since it is constructed substantially flush with the pavement portion 34 of the plate 30 and the pavement portion 15 on the existing reinforced concrete floor slab 14, the steel floor updated (replaced) with the pavement portion 15 of the existing reinforced concrete floor slab 14 The pavement 34 of the plate 30 can be made continuous. For this reason, it is possible to cancel the lane restriction that has been performed at the time of replacement of the floor slab and allow the vehicle to travel 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. And it can be securely connected firmly.
Further, since the friction surface treatment by metal spraying (aluminum spraying) is performed on the joint surface around the bolt hole 42c of the splice plate 42, a friction coefficient necessary for high-strength bolt friction welding is secured, The number can be minimized.
In addition, since the existing reinforced concrete floor slab 14 is replaced with a steel floor slab 30 that is much lighter than the reinforced concrete floor slab 14, the steel floor slab 30 can be protruded outward in the bridge width direction from the reinforced concrete floor slab 14, that is, 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 in the bridge width direction is about 2 m to 2.5 m, and a part of the reinforced concrete floor slab is cut and removed in a shape long in the bridge axis direction. The case of replacing with a steel slab will be described.
In the present embodiment, the steps described in the first embodiment are basically repeated in order. Therefore, a detailed description of each process is omitted, and the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted or simplified.

First, under the bridge 10 as shown in FIG. 22, an unillustrated full-scale suspension scaffold is installed, and from this full-length suspension scaffold, removal and improvement of members that interfere with the installation (replacement) of a new steel floor slab, Finish (partially grinder work).
Next, as shown in FIG. 23, among the four main girders in the bridge 10, horizontal rib attachment members 16 are arranged at predetermined intervals in the bridge axis direction above the main girder webs 11a of the two right main girders 11. , Bolted with high strength bolts. In this case, the lateral rib attaching 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 is connected. The lateral rib mounting member 16 is bolted to the web surface.
In addition, after attaching the horizontal rib attachment member 16 to the main girder 11, the one side lane control of upper traffic is performed as needed. When one-side lane regulation is performed, temporary guards 17 are erected at predetermined intervals in the bridge axis direction at the center in the width direction (bridge width direction) of the road surface.

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

Next, as shown in FIGS. 26 and 27, a new steel floor slab 30A is installed on the removal portion 20A so as to cover the remaining reinforced concrete 21, and the bridge width direction of the lateral rib 33 of the steel floor slab 30A is set. The end of the horizontal rib 33 is connected to the nearest main girder web 11a in a state where the end surface of the transverse 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. By rigidly coupling with the rib attachment member 16, the lateral rib 33 and the nearest main girder web 11a are rigidly coupled. Moreover, before this horizontal rib coupling | bonding process, the height adjustment of the steel deck 30A is performed with the height adjustment bolt 40 (not shown) mentioned above.
The steel floor slab 30A of this embodiment includes five lateral ribs 33 at a predetermined interval (in the case of the figure, an interval of 2.25 m). In addition, although the space | interval between the adjacent horizontal ribs 33 is mainly decided by transport, if the space | interval of a main girder is about 2.5 m usual, the length of the steel deck 30A in the bridge width direction will be about 2.5 m or more Therefore, the interval between the lateral ribs 33 can be made relatively large. At that time, the length of the steel deck 30A in the direction of the bridge axis is maximum at a transport limit of about 12 m, so the number of the lateral ribs 33 can be five at intervals of 2.25 m. However, depending on the construction and other conditions, the length of the steel slab in the direction of the bridge axis can be appropriately taken, and the transverse ribs can be arranged at intervals of a maximum of about 2.25 m.

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

Next, as shown in FIG. 30 and FIG. 31, while arrange | positioning so that the following steel deck 30B may be covered on the remaining reinforced concrete 21 (refer FIG. 28) to the said removal part 20B, height adjustment bolt 40 (FIG. 11) to adjust the height of the steel slab 30B (steel slab placement step).
Next, the lateral rib 33 of the steel deck 30B is rigidly coupled to the main girder web 11a closest to the end at the end in the bridge width direction of the lateral rib 33 by the lateral rib mounting member 16 (the lateral rib rigid member). Bonding step).
Next, as shown in FIG. 32, the rightmost main girder 11 and the steel floor slab 30A are coupled by a shearing force transmission member 50 similar to that of the first embodiment that transmits a shearing force in the direction of the bridge axis. At the same time, the main girder 11 and the steel deck 30B are coupled by a shearing force transmitting member 50 that transmits a shearing force in the direction of the bridge axis (steel deck coupling step). Note that the attachment of the shear force transmission member 50 can also be performed after the traffic regulation is released.
Further, the steel floor slabs 30A and 30B adjacent to each other in the bridge axis orthogonal direction (left and right direction in FIG. 32) are joined by the inter-panel joint 35. The inter-panel joint 35 includes two joint plates 35d and 35d. The joint plates 35d and 35d are arranged so as to straddle the joint portions of the steel decks 30A and 30B adjacent to each other in the direction perpendicular to the bridge axis, and the deck plates 31 and 31 of the steel decks 30A and 30B are placed by the joint plates 35d and 35d. The steel decks 30 </ b> A and 30 </ b> B are joined to each other by being sandwiched and fastened by the high strength bolt 46. Further, the space between the pavement portions 34, 34 of the steel floor slabs 30A, 30B is filled with the pavement portion 34a.
Finally, a temporary fixing plate 55 is bridged between the steel floor slab 30B replaced this time and the reinforced concrete floor slab 14 adjacent to the steel floor slab 30B in the bridge width direction and the bridge axis direction. On the upper surface side, a temporary pavement (not shown) is applied substantially flush with the pavement 34 provided in advance on the upper surfaces of the steel decks 30A and 30B and the pavement 15 on the reinforced concrete deck 14.

In this way, after the replacement of the steel slabs 30A and 30B is completed, the temporary traffic restriction is canceled and the construction zone can be passed.
When replacing the next steel floor slabs 30A and 30B, the above steps are basically repeated in sequence. Further, similarly, the necessary number of steel slabs 30A and 30B are sequentially replaced, so that new steel slabs 30A and 30B are newly installed in place of the reinforced concrete slab 14 by a desired distance in the bridge axis direction.

  According to the present embodiment, the same effect as in the first embodiment can be obtained, and when the distance between the main girders adjacent in the bridge width direction is as narrow as about 2 m to 2.5 m, it can be efficiently performed. There exists an advantage that it can replace with the reinforced concrete floor slab 14, and can newly install new steel floor slab 30A, 30B.

  In the present embodiment, the steel floor slab 30B is installed after the steel floor slab 30A is installed. Conversely, the steel floor slab 30B is installed and then the steel floor 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 includes a first lateral rib mounting member (transverse rib mounting) instead of the lateral rib mounting member 16 of the bridge 10 of the first embodiment. Member) 70 and a second lateral rib attachment member (lateral rib attachment member) 71, and a shear force transmission member 72 instead of the shear force transmission member 50.
In addition, you may comprise so that the bridge 10B may be provided with three or more horizontal rib attachment members.

The first lateral rib attachment member 70 and the second lateral rib attachment member 71 are fixed to the left side of the main girder web 11a of the main girder 11.
In the present embodiment, a plurality of reinforcing ribs (horizontal ribs) 11e are fixed to the main beam 11a of the main beam 11. The plurality of reinforcing ribs 11e are arranged on the left web surface of the main girder web 11a so as to be separated from each other in the vertical direction. Each of the plurality of reinforcing ribs 11e extends in the bridge axis direction.
Among the plurality of steel decks 30 adjacent to each other in the bridge 10B in the bridge 10B, the steel deck 30 located on the right side is also referred to as a steel deck 30C, and the steel deck 30 located on the left side is referred to as a steel deck. 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 deck 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 covered.

  As shown in FIGS. 33 and 35, the first horizontal rib mounting member 70 is configured in the same manner as the horizontal rib mounting member 16, and includes a fixed plate 70a and a connecting plate 70b. The fixed plate 70a is formed in a rectangular plate shape. The fixed plate 70a is disposed such that the thickness direction of the fixed 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 vertical length of the fixed plate 70 a is about half of the vertical length of the fixed plate 16 a of the lateral rib mounting member 16.

The connection plate 70b is formed in a generally rectangular plate shape. The connecting plate 70b protrudes from the center in the width direction of the fixed plate 70a in a direction perpendicular to the plate surface of the fixed plate 70a. The connecting plate 70b is disposed so that the thickness direction of the connecting plate 70b is the bridge axis direction. The left end of the connecting plate 70b extends to the left end of the extension member 31c of the steel deck 30C. The length of the connection plate 70b in the vertical direction is approximately the same as the length of the fixed plate 70a in the vertical direction.
A notch 70c is formed at the lower edge of the connecting 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 disposed in the middle portion of the connecting plate 70b in the vertical direction and extends in the bridge width direction. In addition, the 1st horizontal rib attachment member 70 does not need to be provided with the reinforcement rib 70d.
In the present embodiment, the first lateral rib attaching member 70 is disposed between the plurality of reinforcing ribs 11e in the main girder web 11a. In other words, the 1st horizontal rib attachment member 70 is arrange | positioned below the reinforcement rib 11e arrange | positioned uppermost among the some reinforcement rib 11e.

The second lateral rib mounting member 71 is configured in the same manner as the first lateral rib mounting member 70. The second lateral rib attaching member 71 includes a fixing plate 71a, a connecting plate 71b, and a reinforcing rib 71d configured in the same manner as the fixing plate 70a, the connecting plate 70b, and the reinforcing rib 70d of the first lateral rib attaching member 70. In this example, the notch is not formed in the connection plate 71b.
The second lateral rib attachment member 71 is disposed below the first lateral rib attachment member 70. In this example, the entire second horizontal rib mounting member 71 is disposed below the first horizontal rib mounting 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 member 16 of the first embodiment is divided in the vertical direction to constitute the horizontal rib mounting members 70 and 71, the lateral rib mounting member 70, compared to the bending strength of the horizontal rib mounting member 16, The bending strength of 71 as a whole decreases. However, since the horizontal rib attachment members 70 and 71 are shorter in the bridge axis direction than the vertical ribs 32 and the like, the horizontal rib attachment members 16 are arranged in the vertical direction as compared with the case where the vertical ribs 32 and the like are divided in the vertical direction. The reduction amount of the bending strength as a whole of the lateral rib mounting members 70 and 71 divided into two is small. Further, compared to the shear strength of the lateral rib mounting member 16, there is almost no decrease in the shear strength of the lateral 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 horizontal 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.
This is because if the rib attachment members 70 and 71 are attached below the position of the reinforcing rib 11e of the main girder 11, the stress generated in the welded portion between the main girder upper flange 11b and the main girder web 11a is fatigued. This is because it is sufficiently reduced to a level that does not occur. The position at which the reinforcing rib 11e is attached to the main girder 11 is determined by a road bridge indication (edited by the Japan Road Association). When the reinforcing rib 11e is attached to the main girder 11 in the vertical direction, the length L1 is 0.2 times the height of the main girder web 11a. Become. When the reinforcing ribs 11e are attached in two stages, if the height of the main girder web 11a is about 1600 mm, the length L1 is 224 mm from the expression (1600 × 0.14). Further, when the reinforcing rib 11e has one horizontal stage, the height of the main girder web 11a is considered to be about 1500 mm, so the length L1 is 300 mm from the formula (1500 × 0.2).

In recent years, webs with thick-walled cross sections, in which the reinforcing ribs of the main girder are abolished, are also being manufactured. Therefore, 224 mm, which is the length L1 of the rib mounting member when the plate height is 1600 mm and the plate thickness is 9 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 can be said that it is appropriate to secure an interval of 224 mm or more as the length L1.
When buckling is taken into consideration, as described in the road bridge specifications, the maximum strength at the level where there is no reduction in buckling strength when high strength steel SBHS is used for the main girder web 11a. Setting an unstiffened section width to 38 times the plate 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 11a of the main girder 11, a first horizontal rib mounting member configured similarly to the first horizontal rib mounting member 70 and the second horizontal rib mounting member 71 is provided. 70A and the second lateral rib attaching member 71A are bolted. The first horizontal rib mounting member 70A and the second horizontal rib mounting member 71A differ 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 floor slab 30C, the lateral rib 33B of the steel floor slab 30D, and the connection plate 70b of the first lateral rib mounting member 70 are joined together 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 vertical direction. The upper end of the first splice plate 75 is disposed immediately below the deck plate 31 of the steel decks 30C and 30D. The lower end of the first splice plate 75 extends to the middle portion of the connection plate 70b in the vertical direction. The extension member 31 c, the lateral rib 33 </ b> B, and the connection plate 70 b are joined by a high-strength bolt 76 using the first splice plate 75.

  The horizontal rib 33B of the steel deck 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 together 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 to the middle portion of the connection plate 70b in the up-down direction. A gap T <b> 1 is formed between the second splice plate 77 and the first splice plate 75. The lower end of the second splice plate 77 extends to the lower end of the connection plate 71b in the vertical direction. The lateral rib 33B, the connecting plate 70b, and the connecting plate 71b are joined by a high-strength bolt 78 using the second splice plate 77.

That is, the connecting plate 70b is joined to the lateral rib 33B via the first splice plate 75 and the second splice plate 77, respectively. The gap T1 is disposed in the middle portion of the connecting plate 70b in the vertical direction.
On the other hand, 70 A of 1st horizontal rib attachment members and the 2nd horizontal rib attachment member 71A, and the horizontal rib 33A of the steel deck 30C are joined by the splice plate 77A, respectively.

As shown in FIG. 36, the pair of shearing force transmission 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 transmission 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 spaced from each other 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 2nd piece 81 is arrange | positioned on the outer side of a pair of downward extension vertical rib 32A which pinches the remaining reinforced concrete 21 in a bridge width direction. The high strength bolt 85 is disposed at the same position as the high strength bolt 84 in the vertical direction.
The second piece 81 is fixed to the downwardly extending vertical rib 32A by a plurality of high-strength bolts 85 that are spaced apart from each other 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. The first end of the connecting piece 82 is continuous with the first piece 80. A second end, which is the end opposite to the first end of the connecting piece 82, continues to the second piece 81. The connecting piece 82 straddles the lower end of the vertically 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, for example, by bending a steel plate.
By fixing the shear force transmitting member 72 to the main girder 11 and the downwardly extending vertical rib 32A of the steel deck 30C, the steel deck 30C is displaced in the bridge width direction with respect to the main girder 11. It becomes easy to cope with the liner plates 60, 61 and the like.

The bridge floor slab replacement method of the present embodiment for configuring the bridge 10B configured as described above is as follows.
In the present embodiment, the steps described in the first embodiment are basically repeated in order. Therefore, a detailed description of each process is omitted, and the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted or simplified.
In the reinforced concrete floor slab removing step, the first lateral rib mounting member 70 and the second lateral rib mounting member 71 are respectively bolted to the main beam 11a of the main beam 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 so 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. The main girder web 11a is bolted.
It is assumed that the steel decks 30C and 30D are replaced in the bridge 10B by performing the above-described steps.

  In the transverse rib rigid joining step after the steel deck slab placement step, the transverse rib 33B of the steel deck 30D is bolted to the first transverse rib attaching member 70 and the second transverse rib attaching member 71, respectively. More specifically, the extension member 31c of the steel floor slab 30C, the lateral rib 33B of the steel floor slab 30D, and the connection plate 70b of the first lateral rib mounting member 70 are joined together by the first splice plate 75. The horizontal rib 33B of the steel deck 30D, the connecting plate 70b of the first horizontal rib mounting member 70, and the connecting plate 71b of the second horizontal rib mounting member 71 are joined together by the second splice plate 77.

In the steel deck connection process, the first piece 80 of the shearing force transmitting member 72 is fixed to the main girder web 11 a of the main girder 11 with a high-strength bolt 84. The second piece 81 of the shearing force transmission member 72 is fixed to the lower extending vertical rib 32A of the steel deck 30C with a high-strength bolt 85.
By performing the above steps, all steps of the method for 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 the upper edge of the connecting 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 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 relatively long, and the length L1 is 0 of the height of the main girder web 11a. .2 times 300 mm. This 0.2 times is determined in accordance with the mounting position when the reinforcing rib defined in the road bridge specification is one-stage.
With reference to the road bridge specifications, the elastic modulus (Young's modulus) E of members made of steel such as steel decks 30C and 30D, main girder 11 is set to 200 kN / mm ² and Poisson's ratio μ is set to 0.3. did. The amorphous material 47 is mortar, the elastic modulus E is 26.5 kN / mm ² , and the Poisson's ratio μ is 0.167.

A predetermined wheel load was applied downward to the bridge 10B. At this time, the stress range at the position P1 joined to the main girder upper flange 11b in the main girder web 11a was 20.6 N / mm ² . Since the position P1 is a welded portion, 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 1st horizontal rib attachment member 70 in the main girder web 11a is a part joined by metal touch. For this reason, the stress range at the position P2 is not important as fatigue resistance characteristics.
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 lateral rib 33B was 35.0 N / mm ² .

FIG. 38 shows an analysis model of the bridge 10C in which the length L2 of the main girder web 11a between the main girder upper flange 11b and the first lateral rib mounting member 70 in the vertical direction is relatively shortened with respect to the bridge 10B. The length L2 is about 0 to 100 mm, which is at most 10 times the thickness of the main girder web 11a. In the bridge 10 </ b> C, the first splice plate 75 is not 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 joined to the main girder upper flange 11b in the main girder web 11a 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 in the outer edge of the lateral 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 become small.

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 lateral rib mounting member 70 to be 224 mm or more, the position joined to the main girder upper flange 11b in the main girder web 11a. The fatigue range of the main girder 11 can be improved by reducing the stress range of the portion corresponding to P1.
As the horizontal rib mounting member, a first horizontal rib mounting member 70 and a second horizontal rib mounting member 71 are provided. Accordingly, since the entire lateral rib mounting members 70 and 71 can be configured to have predetermined bending strength and shear strength, the mass per one of the first lateral rib mounting member 70 and the second lateral rib mounting member 71 is reduced. be able to. Thereby, an operator can carry easily each of the 1st horizontal rib attachment member 70 and the 2nd horizontal rib attachment member 71 manually.
The first lateral rib mounting member 70 that is smaller than the lateral rib mounting member 16 can be disposed in a narrow space between the reinforcing ribs 11e of the main beam 11.

The first splice plate 75 joins the lateral rib 33B and the first lateral rib mounting member 70 of the steel floor slab 30D, and the second splice plate 77 includes the lateral rib 33B, the first lateral rib mounting member 70 and the steel floor slab 30D. The 2nd horizontal rib attachment member 71 is joined. A portion located between the first splice plate 75 and the second splice plate 77 in the lateral rib 33B in order to join not only the second lateral rib attachment member 71 but also the first lateral rib attachment member 70 by the second splice plate 77. It is possible to avoid stress concentration on the surface.
In the shearing force transmission member 72, the position where the first piece 80 is fixed to the main girder web 11a by the high-strength bolt 84, and the second piece 81 to the lower extending vertical rib 32A of the steel deck 30C by the high-strength bolt 85. Since the fixed position is the same in the vertical direction, the shear force transmitting member 72 is restrained from generating a moment around the axis along the horizontal plane. For this reason, it is less necessary for the shear force transmission member 72 to withstand the moment, the weight of the shear force transmission member 72 can be reduced, and the number of bolts required for installation can be reduced.

In the present embodiment, the first splice plate 75 is the extension member 31c of the steel deck 30C, the lateral rib 33B of the steel deck 30D, the connecting plate 70b of the first lateral rib mounting member 70, and the second lateral rib mounting member. 71 connecting plates 71b may be joined, and the second splice plate 77 may be configured to join the transverse ribs 33B of the steel deck 30D and the joining plates 71b of the second transverse rib attaching members 71.
Even if comprised in this way, there can exist an effect similar to the bridge | bridging 10B and floor slab replacement | exchange method of this Embodiment.
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. As shown in FIG.

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 attachment member 18 High-strength bolt 20, 20A, 20B removal part 21 Remaining reinforced concrete 22 Covered concrete 30, 30A, 30B Steel floor slab 31 Deck plate 32 Vertical rib 32A Downward extending vertical rib (rib)
33 (33A, 33B) Horizontal rib 33a One end surface 33d Both end surfaces 33e End portion 34 Pavement portion 42, 42A, 77A, 88 Splice plate 42c Bolt hole 45 High strength bolt 47 Indeterminate material 50, 72 Shear force transmission member 55 Temporarily fixed Board 56 Temporary pavement 70 First horizontal rib mounting member (horizontal rib mounting member)
71 Second lateral rib mounting member (lateral rib mounting member)
75 First splice plate 77 Second splice plate 80 First piece 81 Second piece 82 Connection piece 84 High strength bolt (first fixing member)
85 High-strength bolt (second fixing member)
L1 length

Claims (24)

A structure of a bridge constructed by replacing a part of a reinforced concrete slab supported by a main girder of a bridge with a steel slab,
Of the reinforced concrete floor slab, the remaining reinforced concrete that is left and removed except the part provided on the upper surface side of the main girder upper flange of the main girder,
Of the reinforced concrete slab, a steel slab disposed so as to cover the remaining reinforced concrete on a removal portion formed by removing the portion other than the portion provided on the upper surface side of the upper girder upper flange of the main girder Prepared,
The steel slab 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 surface or both end surfaces of the lateral rib in the bridge width direction is opposed to the web surface of the main girder web of the main girder,
The lateral rib is rigidly coupled to the main girder web closest to the end at the end of the lateral rib in the bridge width direction,
The bridge structure characterized in that the main girder and the steel deck are joined by a shearing force transmission member that transmits a shearing force in the direction of the bridge axis.   The bridge structure according to claim 1, wherein the covering concrete on the upper part of the remaining reinforced concrete is removed.   The bridge of claim 1 or 2, wherein a height adjusting bolt capable of adjusting a height of the steel slab is screwed to the steel slab so as to be able to contact the remaining reinforced concrete. Construction.   The bridge structure according to any one of claims 1 to 3, wherein an amorphous material is filled between the steel deck, the main girder upper flange, and the remaining reinforced concrete. A paving portion is preliminarily constructed on the steel floor slab disposed in the removal portion, and a temporary fastening plate is bridged between the steel floor slab and the reinforced concrete floor slab adjacent to the steel floor slab,
The temporary pavement part is constructed on the upper surface side of the temporary fixing plate substantially flush with the pavement part and the pavement part on the reinforced concrete floor slab. Structure of the described bridge.   The horizontal rib mounting member is bolted to the main girder web, and the end of the horizontal rib is bolted to the horizontal rib mounting member. Bridge structure.   The bridge structure according to claim 6, wherein a vertical length of the main girder web between the main girder upper flange and the lateral rib mounting member 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,
The bridge structure according to claim 6 or 7, wherein a friction surface treatment by metal spraying is performed on a joint surface around a bolt hole through which the high-strength bolt is inserted in the splice plate.   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 lateral rib mounting member disposed below the first lateral rib mounting member,
A first splice plate for joining the lateral rib and the first lateral rib mounting member to each other;
A second splice plate for joining the lateral rib, the first lateral rib mounting member and the second lateral rib mounting member to each other;
The bridge structure according to any one of claims 6 to 9. As the lateral rib mounting member,
A first lateral rib mounting member;
A second lateral rib mounting member disposed below the first lateral rib mounting member,
A first splice plate that joins the lateral rib, the first lateral rib mounting member and the second lateral rib mounting member to each other;
A second splice plate for joining 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. The shear force transmission member is
A first piece fixed to the main girder web by a first fixing member;
A second piece fixed to a rib joined to the lower surface of the deck plate by a second fixing member disposed at an equivalent position in the vertical direction to the first fixing member;
A connecting piece continuous to each of the first piece and the second piece;
The bridge structure according to any one of claims 1 to 11, wherein the bridge structure is provided. A method for replacing a slab of a bridge in which a part of a reinforced concrete slab supported by a main girder of a bridge is replaced with a steel slab,
The steel slab has a lateral rib 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 of the lateral rib in the bridge width direction is the nearest of the main girder. It faces the web surface of the main girder web,
By removing portions other than the portion provided on the upper surface side of the main girder upper flange of the main girder in the reinforced concrete floor slab, the removal portion is provided and the remaining reinforced concrete is left on the upper surface side of the main girder upper flange. Reinforced concrete floor slab removal process,
A steel floor slab placement step of placing the steel floor slab on the remaining reinforced concrete on the removal portion;
A lateral rib rigid coupling step of rigidly coupling the lateral rib at the end of the lateral rib to the main girder web closest to the end; and
A steel slab coupling step for coupling the main girder and the steel slab by a shearing force transmitting member that transmits a shearing force in a bridge axis direction;
A method for replacing a floor slab of a bridge, characterized by comprising:   The bridge slab replacement method according to claim 13, wherein in the reinforced concrete floor slab removing step, the covered concrete on the upper part of the remaining reinforced concrete is removed. A height adjusting bolt capable of adjusting the height of the steel slab is screwed to the steel slab so as to be able to contact the remaining reinforced concrete,
The bridge slab replacement method according to claim 13 or 14, wherein the height of the steel slab is adjusted by turning the height adjusting bolt after the steel slab arranging step.   The irregularly shaped material is filled between the steel slab, the main girder upper flange, and the remaining reinforced concrete after the steel slab disposing step. How to replace the floor slab of the bridge described in 1. The pavement part is constructed on the steel floor slab arranged in the removal part,
After the steel slab placement step, a temporary fastening plate is bridged between the steel slab and the reinforced concrete slab adjacent to the steel slab and not replaced by the steel slab,
The temporary paving portion is constructed on the upper surface side of the temporary fixing plate so as to be substantially flush with the paving portion and the paving portion 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 deck installation step. The bridge slab replacement method according to any one of the above items.   The bridge slab replacement method according to claim 18, wherein a 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 horizontal rib to the horizontal rib mounting member,
High-strength bolt friction joining by sandwiching the lateral rib mounting member and the end of the lateral rib by a splice plate and fastening with a high-strength bolt,
The bridge floor slab replacement method according to claim 18 or 19, wherein a friction surface treatment by metal spraying is performed in advance on a joint surface around a bolt hole through which the high-strength bolt of the splice plate is inserted.   A plurality of the horizontal rib mounting members are bolted to the main girder web, and the horizontal ribs are bolted to the plurality of horizontal rib mounting members, respectively, after the steel deck installation step. The bridge floor slab replacement method according to any one of claims 18 to 20. A first lateral rib mounting member, which 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 coupling 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 the horizontal rib, the first horizontal rib mounting member, and the second horizontal rib mounting member are joined to each other by a second splice plate. Version replacement method. A first lateral rib mounting member, which 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 coupling step,
The first splice plate joins the lateral rib, the first lateral rib mounting member and the second lateral rib mounting member to each other,
The bridge floor slab replacement 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 deck joining process,
The first piece of the shear force transmission member is fixed to the main girder web by a first fixing member,
The second piece of the shear force transmission member is fixed to the rib attached to the lower surface of the deck plate by a second fixing member arranged at the same position in the vertical direction as the first fixing member,
The bridge floor slab replacement method according to any one of claims 13 to 23, wherein the connection pieces of the shear force transmission member are connected to the first piece and the second piece, respectively.

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