Temporary steel floor slab and floor slab replacement method

Abstract

To provide a temporary steel floor slab and a floor slab replacement method capable of achieving early traffic opening in the replacement work of the floor slab.SOLUTION: A temporary steel floor slab 1 installed between an existing floor slab 2 and a newly installed floor slab 3 when replacing the existing floor slab 2 installed on a girder 5 with the new floor slab 3 is provided with a floor slab body part 10 installed on the girder 5 and a support part 20 projecting from the floor slab body part 10, the support part supporting the new floor slab 3 arranged adjacent to the temporary steel floor slab. The floor slab body part 10 is laid over the plurality of rows of girders 5, 5 arranged at predetermined intervals in the width direction of the road surface, and the support part 20 is arranged between the girders 5, 5.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a temporary steel deck and a deck replacement method. [Background technology]

[0002] A known example of a deck slab used in roads and the like is that described in Patent Document 1. The deck slab in Patent Document 1 is made of precast concrete plates and is laid continuously. Adjacent decks are installed at a predetermined interval, with reinforcing bars protruding from each other's end faces. Anchorages are formed at the tips of the reinforcing bars protruding from both end faces, and the reinforcing bars are arranged parallel to each other at a predetermined interval and joined by open lap joints. A filler such as a fiber-reinforced filler is filled between the end faces. The use of such a joint structure enables labor savings during construction and shortens the construction period. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-55531 Summary of the Invention [Problem to be solved by the invention]

[0004] Meanwhile, replacement work of decks laid on roads is carried out with the roads closed. In replacement work, the existing decks are removed after the pavement has been removed, new decks are laid, and then filler material is filled between the new decks. In recent years, there has been a demand to open closed roads to traffic on weekends, but in order to open them to traffic, it is necessary to wait for the filler material to develop the required strength. In the structure of Patent Document 1, for example, the required strength is 55.1 N / mm 2 It took about a day at an ambient temperature of 20°C for the effect to appear, leaving room for an earlier reopening to traffic. From this perspective, the present invention aims to provide a temporary steel deck and a deck replacement method that can achieve early reopening of traffic during deck replacement work. [Means for solving the problem]

[0005] The first invention to solve such problems is a temporary steel deck that is installed between an existing deck installed on a girder and a newly installed deck when replacing an existing deck installed on a girder with a new deck, and is characterized in that it comprises a deck main body portion installed on the girder and a support portion extending from the deck main body portion, and the support portion supports the new deck placed next to the temporary steel deck. According to the temporary steel deck of the present invention, the temporary steel deck is made of steel, so it has great strength and can obtain the required strength without filling the gap between the existing deck and the temporary steel deck. Furthermore, since the new deck placed next to the temporary steel deck is supported by the support section, the required strength can be obtained without filling the gap between the temporary steel deck and the new deck. Therefore, there is no need for a curing period for the gap material, and early reopening of the road to traffic can be achieved.

[0006] In the temporary steel deck of the present invention, it is preferable that the deck body is spanned across multiple rows of girders arranged at predetermined intervals in the width direction of the road surface, and the support parts are arranged between the girders. With this configuration, the new deck can be supported without interference between the support parts and the girders. In the temporary steel deck of the present invention, the support portion preferably comprises a hanging portion hanging downward from the bottom surface of the deck body portion and a protruding portion protruding from the lower end of the hanging portion below the adjacent new deck. With this configuration, the temporary steel deck can be installed at an angle, so the support portion can be inserted below the new deck, making it easy to install the temporary steel deck.

[0007] In the temporary steel deck of the present invention, it is preferable that the support section is provided with an expansion jack for adjusting the support position of the new deck. With this configuration, the new deck can be installed easily and accurately. In the temporary steel deck of the present invention, it is preferable that the support portions are arranged in a plurality of rows in the width direction of the road surface. With this configuration, the new deck can be supported in a well-balanced manner. In the temporary steel deck of the present invention, it is preferable that the deck body comprises a flat plate portion and a rising portion, and that a locking member for connecting to the girder is provided on the bottom surface of the flat plate portion. With this configuration, the work of connecting to the girder becomes easier.

[0008] The second invention for solving the above problem is a deck replacement method comprising a deck removal process for removing the existing deck within a predetermined range, a deck installation process for installing at least one new deck at one end of the range and installing a temporary steel deck at the other end of the range, a running board installation process for covering the gaps before and after the temporary steel deck with running boards, and a temporary pavement laying process for laying temporary pavement on the new deck, the temporary steel deck, and the running board, wherein in the deck installation process, the support parts of the temporary steel deck support the new deck placed next to the temporary steel deck. According to the deck replacement method of the present invention, the temporary steel deck installed between the existing deck and the new deck is made of steel, so it has great strength and can achieve the required strength without filling the gap between the existing deck and the temporary steel deck. Furthermore, since the new deck placed next to the temporary steel deck is supported by the support section, the required strength can be achieved without filling the gap between the temporary steel deck and the new deck. Therefore, a curing period for the gap material is not required, and early reopening to traffic can be achieved. Furthermore, when installing a new deck after opening to traffic, the temporary steel deck installed the day before can be easily removed, allowing for early progress to the next process.

[0009] The deck replacement method of the present invention preferably further comprises a removal step of removing the temporary pavement, the running board, and the temporary steel deck. With this configuration, the next step can be carried out quickly. [Effects of the Invention]

[0010] According to the temporary steel deck and deck replacement method of the present invention, it is possible to achieve early reopening of the road to traffic during deck replacement work. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a perspective view showing a state of deck replacement work carried out using a temporary steel deck according to an embodiment of the present invention. [Figure 2] 1 is a cross-sectional view showing a state in which a temporary steel deck according to an embodiment of the present invention is installed at a deck replacement position. FIG. [Figure 3] 1A and 1B are diagrams showing a temporary steel deck according to an embodiment of the present invention, in which (a) is a side view seen from the bridge axis direction, and (b) is a side view seen from a direction perpendicular to the bridge axis. [Figure 4] 1A and 1B are diagrams showing a temporary steel deck according to an embodiment of the present invention, in which (a) is an enlarged side view seen from the bridge axis direction, (b) is an enlarged side view seen from a direction perpendicular to the bridge axis, and (c) is a bottom view of the main part. [Figure 5] These are analytical models of FEM analysis conducted before the deck replacement work, where (a) is an analytical model without countermeasures, (b) is an analytical model with countermeasures, and (c) is an analytical model after the work is completed. [Figure 6] FIG. 1 is a perspective view showing a joint between adjacent deck slabs. [Figure 7] (a) is a cross-sectional view of the PC deck used in the FEM analysis conducted before the deck replacement work, and (b) is a cross-sectional view showing the position where the wheel load acts. [Figure 8] 10 is a graph showing the stress on the underside of the deck calculated by FEM analysis. [Figure 9] 1 is a flowchart of a deck replacement work including a deck replacement method according to an embodiment of the present invention. [Figure 10A] 1A and 1B are diagrams for explaining a deck slab replacement method according to an embodiment of the present invention, in which (a) is a plan view and (b) is a cross-sectional view. [Figure 10B] 1A and 1B are diagrams for explaining a deck slab replacement method according to an embodiment of the present invention, in which (a) is a plan view and (b) is a cross-sectional view. [Figure 10C] 1A and 1B are diagrams for explaining a deck slab replacement method according to an embodiment of the present invention, in which (a) is a plan view and (b) is a cross-sectional view. [Figure 10D] 1A and 1B are diagrams for explaining a deck slab replacement method according to an embodiment of the present invention, in which (a) is a plan view and (b) is a cross-sectional view. [Figure 10E] 1A and 1B are diagrams for explaining a deck slab replacement method according to an embodiment of the present invention, in which (a) is a plan view and (b) is a cross-sectional view. [Figure 10F] 1A and 1B are diagrams for explaining a deck slab replacement method according to an embodiment of the present invention, in which (a) is a plan view and (b) is a cross-sectional view. [Figure 11] 1A and 1B are diagrams for explaining a deck replacement method without countermeasures, in which (a) is a plan view and (b) is a cross-sectional view. DETAILED DESCRIPTION OF THE INVENTION

[0012] The temporary steel deck and deck replacement method according to an embodiment of the present invention will be described with reference to the accompanying drawings. Figure 1 is a perspective view showing the state of deck replacement work carried out using a temporary steel deck, Figure 2 is a cross-sectional view showing the state of the temporary steel deck installed at the deck replacement position, Figure 3 is a diagram showing the temporary steel deck, where (a) is a side view seen from the bridge axis direction and (b) is a side view seen from a direction perpendicular to the bridge axis, and Figure 4 is a diagram showing the temporary steel deck, where (a) is an enlarged side view seen from the bridge axis direction, (b) is an enlarged side view seen from a direction perpendicular to the bridge axis, and (c) is a bottom view of the main part.

[0013] In this embodiment, as shown in FIG. 1, a temporary steel deck 1 and a deck replacement method will be described using an example in which an existing deck 2 installed as a road 8 is replaced with a new deck 3. The existing deck 2 and the new deck 3 (hereinafter, sometimes referred to as "deck 4" when there is no need to distinguish between the existing and new) are precast concrete plates. The deck 4 is installed on a pair of girders 5, 5. The girders 5 are arranged at a predetermined interval in the direction perpendicular to the bridge axis (the width direction of the road surface) and extend in the bridge axis direction. A plurality of decks 4 are arranged along the bridge axis direction. In this embodiment, as also shown in FIG. 2, the deck 4 includes a deck main body portion 6a, a rising portion 6b, and a plate thickness portion 6c. The deck main body portion 6a has a road width equivalent to, for example, two lanes. The rising portion 6b is formed at the outer end of the deck main body portion 6a and forms a parapet for the road. The thick plate portion 6c is formed in a portion where the girders 5, 5 are connected. The thick plate portion 6c reinforces the deck slab main body portion 6a.

[0014] First, we will explain the configuration of the temporary steel deck 1. As shown in Figures 1 and 2, the temporary steel deck 1 is a temporary steel deck that is installed between an existing deck 2 installed on a girder 5 and a newly installed new deck 3 when replacing the existing deck 2 with a new deck 3. The temporary steel deck 1 supports the new deck 3 that is placed next to it. As also shown in Figures 3 and 4, the temporary steel deck 1 comprises a deck main body portion 10 and a support portion 20.

[0015] The deck main body 10 is installed on the girder 5 and spans a pair of girders 5, 5 spaced a predetermined distance apart in the direction perpendicular to the bridge axis (the width direction of the road surface). Each of the pair of girders 5, 5 extends in the bridge axis direction. The deck main body 10 comprises a flat plate portion 11 and a rising portion 12. The flat plate portion 11 constitutes the road substructure and is formed into a flat plate shape by arranging H-shaped steel beams in parallel. The H-shaped steel beams extend perpendicular to the bridge axis and are arranged side by side in the bridge axis direction. A locking member 13 is attached to the bottom surface of the flat plate portion 11 to connect it to the girder 5. The locking member 13 is L-shaped and fits under the upper flange of the girder 5. The temporary steel deck 1 is fixed to the girder 5 by inserting a bolt from the underside of the locking member 13 and pressing the tip of the bolt against the underside of the upper flange. Reinforcing ribs 14 are appropriately installed between the web of the H-shaped steel beam and the upper and lower flanges. The reinforcing ribs 14 are provided at the connection positions with the girder 5 and at the installation positions of the support parts 20. The rising portion 12 is provided at the end of the flat plate portion 11 in the road width direction, and serves to prevent it from falling from the deck slab main body portion 10. The rising portion 12 is formed by erecting multiple H-shaped steel beams. A sliding portion 15 with an inclined surface is formed on the road surface side of the H-shaped steel beams.

[0016] The support part 20 is a member that supports the new deck 3 placed next to the temporary steel deck 1, and is provided at the end of the deck main body 10 in the bridge axis direction. The support part 20 has a hanging part that hangs downward from the bottom surface of the deck main body 10 and a protruding part that protrudes outward from the lower end of the hanging part, and supports the adjacent new deck 3 from below. The support part 20 is provided in a position offset from the installation position of the girder 5 so as not to interfere with the girder 5. The support part 20 is provided in two places: in the part between the pair of girders 5, 5, and inside the inner girder 5, below the protruding part of the deck main body 10. The support part 20 has a bracket 21, a lower connecting plate 22, an extension jack 23, and an upper connecting plate 24. Bracket 21 is a metal plate that is L-shaped in side view and has a hanging plate portion and an overhanging plate portion. The upper edge of the hanging plate portion is welded to the bottom surface of deck slab main body 10. The upper surface of the overhanging plate portion is horizontal. Multiple brackets 21 are provided at predetermined intervals in the direction perpendicular to the bridge axis. Reinforcing ribs 14 are provided on deck slab main body 10 above bracket 21, between the web of the H-shaped steel and the upper and lower flanges. Reinforcing ribs 14 are arranged on the same plane as bracket 21.

[0017] The lower connecting plate 22 is a long, rectangular metal plate in plan view, extending in the direction perpendicular to the bridge axis. The lower connecting plate 22 is hung across and welded to the upper surfaces of the protruding plate portions of adjacent brackets 21, 21.... The lower connecting plate 22 serves as a platform on which the telescopic jacks 23 are installed. The telescopic jacks 23 adjust the height at which the new deck slab 3 is supported, and multiple telescopic jacks 23 are installed upright along the longitudinal direction of the lower connecting plate 22. The telescopic jacks 23 are installed in a direction that allows them to extend and retract vertically, and are located midway between adjacent brackets 21, 21. The telescopic jacks 23 are fixed to the lower connecting plate 22 with bolts inserted from the underside of the lower connecting plate 22. The upper connecting plate 24 is a long, rectangular metal plate in plan view that connects the upper parts of the multiple telescopic jacks 23, 23... and extends in the direction perpendicular to the bridge axis. The lower surface of the upper connecting plate 24 is welded to the upper ends of the telescopic jacks 23. The upper surface of the upper connecting plate 24 becomes the placement surface for the new deck slab 3, and the support portion 20 supports the new deck slab 3 on its surface.

[0018] The temporary steel deck 1 configured in this manner has great strength because it uses a deck made of steel. Therefore, the required strength can be obtained without filling any filler material between the temporary steel deck 1 and the existing deck 2. Furthermore, since the new deck 3 placed next to the temporary steel deck 1 is supported by the support section 20, the required strength can be obtained without filling any filler material between the temporary steel deck 1 and the new deck 3. Therefore, by using the temporary steel deck 1 of this embodiment, there is no need for a curing period for the filler material around the temporary steel deck 1, making it possible to achieve early reopening to traffic.

[0019] In addition, the deck main body 10 of the temporary steel deck 1 is spanned across multiple rows of girders 5, 5, and the support parts 20 are arranged between the girders 5, 5, so that the support parts 20 located at the bottom of the deck main body 10 can support the newly constructed deck 3 without interfering with the girders 5, 5. The support section 20 is equipped with a hanging section that hangs downward from the bottom surface of the deck main body section 10, and an overhanging section that overhangs from the lower end of the hanging section below the adjacent new deck slab 3, so that it can support the new deck slab 3 from below. Furthermore, when installing the temporary steel deck 1, the temporary steel deck 1 can be tilted and moved so that the support section 20 can be inserted below the new deck slab 3. This makes it easy to install the temporary steel deck 1. Furthermore, if the temporary steel deck 1 is installed with the extension jack 23 retracted, and then the extension jack 23 is extended to support the new deck slab 3, installation of the temporary steel deck 1 becomes even easier.

[0020] Next, we will explain the FEM analysis performed using an analytical model of a structure reinforced using the temporary steel deck 1 of this embodiment. Figure 5 shows analytical models of FEM analysis performed before the execution of deck replacement work, where (a) is the analytical model without measures (when the temporary steel deck 1 is not used), (b) is the analytical model with measures (when the temporary steel deck 1 is used), and (c) is the analytical model after the work is completed. Figure 6 is a perspective view showing the joints between adjacent decks, Figure 7(a) is a cross-sectional view of the PC deck used in the FEM analysis performed before the deck replacement work, and (b) is a cross-sectional view showing the wheel load application position, and Figure 8 is a graph showing the stress on the underside of the deck calculated by the FEM analysis.

[0021] The FEM analysis performed in this embodiment used a PC deck (see (a) of Figure 7) from a judgment surface deck replacement project. This PC deck is the type used for the new deck 3, and is reinforced with, for example, D19 rebars arranged at 150 mm intervals in two rows (48 mm apart), one above the other. The girders 5, 5 supporting the PC deck are arranged at a pitch of 3000 mm. The wheel load P has a wheel width of 1750 mm, and is set at two locations: 250 mm from the inner surface of the sliding section 15 of the rising section 12, and 1000 mm inward from the outer wheel load P (see (b) of Figure 7). As shown in Figure 5, three analytical models were used: M1 without countermeasures (see Figure 5(a)), M2 with countermeasures (see Figure 5(b)), and M3 after completion (see Figure 5(c)). In M1 without countermeasures, no temporary steel deck 1 was installed, and the new deck 3 served as the end deck slab, adjacent to the existing deck slab (not shown). No filler material was filled between the new deck slab 3 and the existing deck slab 2. In M2 with countermeasures, the temporary steel deck 1 was installed between the new deck slab 3 and the existing deck slab (not shown), and the end new deck slab 3 was supported from below by the support parts 20 of the temporary steel deck 1. In M3 after completion, filler material was filled between the new deck slabs 3 and between the new deck slab 3 and the existing deck slab (not shown). As shown in Figure 6, joint members 53, each consisting of a rod-shaped member 51 made of reinforcing steel, with a rectangular anchoring plate 52 attached to the tip, are provided between the new slabs 3 to be filled with filler, or between the new slab 3 and the existing slab. The joint members 53 are provided at a predetermined distance from the end faces of the opposing new slabs 3. The joint members 53 protruding from the end face of one new slab 3 and the joint members 53 protruding from the end face of the other new slab 3 are arranged alternately. The anchoring plates 52 are arranged at a predetermined distance from the end face of the opposing new slab 3.

[0022] The results of FEM analysis for these three analytical models are shown in Figure 8. In the case of M1 (without countermeasures), the stress on the underside of the concrete of the new slab 3 after loading remained in a compressive state, but increased by 2.75 from the initial prestress stress. In the case of M2 (with countermeasures), the stress on the underside of the concrete of the new slab 3 after loading increased by 0.84 from the initial prestress stress, but maintained a compressive state without significantly shifting to the tensile state. In the case of M3 (after completion), the stress on the underside of the concrete of the new slab 3 after loading increased by 1.24 from the initial prestress stress, but maintained a compressive state without significantly shifting to the tensile state. From these results, it can be seen that when the temporary steel deck 1 was used as a countermeasure (M2), more prestress stress remained than in the completed state (M3), demonstrating a significant effect.

[0023] Next, the deck replacement method according to this embodiment will be described. Figure 9 is a flowchart of the deck replacement work including the deck replacement method according to the embodiment of the present invention, and Figures 10A to 10F are diagrams for explaining the deck replacement method according to the embodiment of the present invention, where (a) is a plan view and (b) is a cross-sectional view, and Figure 11 is a diagram for explaining the deck replacement method without countermeasures, where (a) is a plan view and (b) is a cross-sectional view.

[0024] As shown in Figure 9, the deck replacement work of this embodiment includes a process (st1) for verifying whether harmful cracks will occur when traffic is opened without filling with filler material. In this verification process, FEM analysis is used to verify whether tensile stress will occur at the deck slab tensile edge when traffic is opened without filling the gap between the new deck slab 3 and the existing deck slab 2 at the end. This FEM analysis is performed using the analytical models M1 without countermeasures and M2 with countermeasures. Note that the FEM analysis using the analytical model M2 confirms that the stress on the underside of the concrete after loading does not shift to the tensile side, preventing cracks from occurring. If the FEM analysis using the analytical model M1 shows that the stress on the underside of the concrete after loading will shift to the tensile side and cracks will occur, the process proceeds to step st2, in which a construction method is carried out that takes measures using the temporary steel deck 1 of this embodiment. On the other hand, if the verification result shows that the stress on the underside of the concrete after loading will not shift to the tensile side and cracks will not occur, the process proceeds to step st3, in which a construction method is carried out using a lining plate to open the concrete to traffic without filling the filler material.

[0025] In step st2, construction is carried out in accordance with the deck replacement method of the present invention. The deck replacement method includes a deck removal process, a deck installation process, a running board installation process, and a temporary pavement laying process. The slab removal process is a process of removing a predetermined area of ​​the existing slab 2. In the slab removal process, the asphalt A of the route including the area 9 where the slab will be replaced is peeled off from the state of the road 8 before construction (see FIG. 10A), and the existing slab 2 is removed (see step st2a in FIG. 9 and FIG. 10B). The deck installation process is a process of installing at least one new deck slab 3 at one end of the range 9, and installing a temporary steel deck 1 at the other end of the range 9. In the deck installation process, first the new deck slab 3 is installed (step st2a in Figure 9), and then the temporary steel deck 1 is installed (step st2b in Figure 9, see Figure 10C). At this time, the support part 20 of the temporary steel deck 1 supports the end of the new deck slab 3 on the side of the temporary steel deck 1 from below. After that, filler material (filling concrete) 31 is filled into the gaps between the adjacent new deck slabs 3, 3 (see step st2c in Figure 9 and Figure 10D). No filler material is filled into the gaps between the temporary steel deck 1 and the new deck slab 3, and between the temporary steel deck 1 and the existing deck slab 2.

[0026] The running plate installation process is a process of covering the gaps at the front and rear of the temporary steel deck 1 (the gap between the temporary steel deck 1 and the new deck 3, and the gap between the temporary steel deck 1 and the existing deck 2) with running plates 32. In the running plate installation process, the running plates 32 are hung across the decks on both sides of the gap, and the running plates 32 cover the gap from above (see step st2d in Figure 9 and Figure 10E). The temporary pavement laying process is a process of laying temporary pavement on the new deck slab 3, the temporary steel deck 1, and the running board 32. The temporary pavement is asphalt A1 for temporary pavement. In the temporary pavement laying process, in addition to the new deck slab 3, the temporary steel deck 1, and the running board 32, the temporary pavement asphalt A1 is also laid on the existing deck slab 2 from which the asphalt A has been removed (see step st2e in Figure 9 and Figure 10F).

[0027] Once the temporary pavement is laid, the deck replacement work is temporarily suspended and the road is reopened to traffic (step ST2F in Figure 9). After a certain period of time has passed, the deck replacement work is resumed. After the work resumes, the temporary pavement is first removed (step ST2G in Figure 9), and then the running board 32 and temporary steel deck 1 are removed, after which the new deck 3 is installed (not shown in the flowchart in Figure 9). After that, if all deck replacement has been completed, gaps before and after the new deck slab 3 are filled with filler material (step st2h in Figure 9). If deck replacement is not complete at this point, return to step st2a and repeat the process up to step st2g. Then, after laying the asphalt for the actual paving on the new deck slab 3 filled with filler material (step st2i in Figure 9), the road is opened to traffic (step st2j in Figure 9). This completes the deck replacement work.

[0028] According to the deck replacement method of this embodiment, the temporary steel deck 1 installed between the existing deck 2 and the new deck 3 is made of steel and therefore has great strength, so the required strength can be obtained without filling any filler material between the existing deck 2 and the temporary steel deck 1. Furthermore, because the new deck 3 is supported by the support parts 20, the required strength can be obtained without filling any filler material between the temporary steel deck 1 and the new deck 3. Therefore, a curing period for the filler material is not required, and early reopening of the road to traffic can be achieved. Furthermore, because the gaps before and after the temporary steel deck 1 are covered with running boards 32, temporary paving can be easily laid. Furthermore, when installing the new deck 3 after the road is opened to traffic, the temporary steel deck 1 that was installed the day before the road is opened to traffic can be easily removed, allowing the next process to proceed quickly.

[0029] In step st3, the road is reopened to traffic without filling the gap material using a covering plate instead of a temporary steel deck 1. The replacement work in step st3 is a known construction method. In step st3, first, the asphalt of the route including the area where the deck is to be replaced is removed from the state of the road before construction, the existing deck is removed, and then a new deck is installed (step st3a in Figure 9). Then, gaps between adjacent new decks 3, 3 are filled with gap material 31 (step st3b in Figure 9, see Figure 11). Here, gaps between the new deck 3 and the existing deck 2 are not filled with gap material. The gaps between the new deck 3 and the existing deck 2 are filled with gap material in the next day's cycle.

[0030] Next, the gap between the new slabs 3, 3 and the gap between the new slab 3 and the existing slab 2 are covered with running plates (covering plates) 32 (step st3c in Figure 9). Here, the running plates 32 are placed across the slabs on both sides of the gap, and the running plates 32 cover the gap from above (see Figure 10E). After that, asphalt A2 for the main pavement is laid on top of the existing slab 2 from which the new slab 3, running plates 32, and asphalt A have been removed (step st3d in Figure 9, see Figure 11). Once the actual pavement is laid, the road is reopened to traffic (step ST3e in Figure 9). After that, if all deck replacement is complete, the construction is finished. If deck replacement is not complete at this point, the process returns to step ST3a, and steps ST3a to ST3e are repeated. There is no problem with the construction method of step ST3 above, as no harmful cracks will occur.

[0031] Although the embodiments for carrying out the present invention have been described above, the present invention is not limited to the above-described embodiments, and appropriate design changes are possible without departing from the spirit of the present invention. For example, in the above-described embodiments, the support portion 20 is formed by integrating the bracket 21 and the lower connecting plate 22, and the extension jack 23 is installed on the lower connecting plate 22, but the present invention is not limited to this. For example, a structure in which L-shaped brackets are individually attached to the deck slab main body 10 and an extension jack 23 is attached to each bracket may also be used.

[0032] In the above embodiment, the joints between the new deck slabs 3, 3 are configured such that joint members 53 each having an anchoring plate 52 at the tip of a rod-shaped member 51 extend from the end faces of the opposing new deck slabs 3, and filler material is filled between them, but this is not limited to this. Reinforcement loop joints extending from the end faces of the new deck slabs may also be used as the joints between the new deck slabs. [Explanation of symbols]

[0033] 1 Temporary steel deck 2 Existing deck 3 New deck 5 digits 10 Deck body 11 Flat plate part 12 Rising section 20 Support part 23 Telescopic Jack 31 Filling material 32 Running board

Claims

1. A temporary steel deck installed between an existing deck and a newly installed deck when replacing an existing deck installed on a girder with a new deck. A deck slab main body portion is installed on the girder, and a support portion extends from the deck slab main body portion, The support portion supports the new deck slab arranged next to the temporary steel deck slab. A temporary steel deck characterized by:

2. The deck slab main body is spanned across a plurality of rows of girders arranged at predetermined intervals in the width direction of the road surface, The support is disposed between the beams.

2. The temporary steel deck according to claim 1.

3. The support portion includes a hanging portion hanging downward from the bottom surface of the deck body portion, and a protruding portion protruding downward from the lower end of the hanging portion to the adjacent new deck.

3. The temporary steel deck according to claim 1 or 2.

4. The support section is provided with an expansion jack that adjusts the support position of the new floor board.

4. The temporary steel deck according to claim 3,

5. The support portions are arranged in a plurality of rows in the width direction of the road surface.

3. The temporary steel deck according to claim 2.

6. The deck body portion includes a flat plate portion and a rising portion, A locking member for connecting to the beam is provided on the bottom surface of the flat plate portion.

3. The temporary steel deck according to claim 2.

7. In the deck replacement method, the existing deck installed on the girder is replaced with a new deck. a slab removal process of removing the existing slab within a predetermined range; A deck installation process in which the new deck is installed by leaving a gap for one sheet of the existing deck that has not been removed, and a temporary steel deck is installed between the new deck and the existing deck; A filler filling process of filling gaps between the installed new deck slabs with filler; a running plate installation process for covering the gap between the new deck and the temporary steel deck and the gap between the temporary steel deck and the existing deck with a running plate; a temporary pavement laying step of laying temporary pavement on the new deck, the temporary steel deck, and the running plate; In the deck installation step, the support portion of the temporary steel deck supports the new deck arranged next to the temporary steel deck. A deck replacement method characterized by the following.

8. The method further includes a removal step of removing the temporary pavement, the running board, and the temporary steel deck plate. The deck replacement method according to claim 7.

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