Floor slab erection method

Abstract

To shorten the working time required for floor slab erection.SOLUTION: A floor slab erecting method includes an installation step of installing a trailing floor slab 20B adjacent to a preceding floor slab 20A installed previously, a fastening step of fastening a preceding floor slab 20A and a trailing floor slab 20B by a fastening member 40 with a spacer 40 interposed in a gap G1 between the preceding floor slab 20A and the trailing floor slab 20B, and a moving step in which at least one of a conveying truck 16 for conveying a floor slab 2b different from the preceding floor slab 20A and the following floor slab 20B and lifting trucks 15, 17 for lifting the other floor slab 2b moves the upper surfaces of the preceding floor slab 20A and the trailing floor slab 20B as a traveling surface S1.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a deck erection method. [Background technology]

[0002] Patent Document 1 discloses a deck erection method in which precast concrete deck slabs are installed in order on main girders extending in the bridge axis direction. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-104972 Summary of the Invention [Problem to be solved by the invention]

[0004] Generally, deck erection work requires the closure of at least one lane of traffic, so it is necessary to complete the work as quickly as possible.Deck erection work is nearly completed by pouring concrete between the installed decks and connecting the decks in the bridge axis direction, but with the deck erection method described in Patent Document 1, rails are installed on the installed decks, on which travel carriages for transporting the decks and lifting carriages for lifting the decks run, and therefore concrete cannot be poured and cured between the decks until the rail removal work is complete, making it difficult to further shorten the work time required for deck erection and reduce work costs.

[0005] The present invention aims to reduce the work time required for erecting a deck. [Means for solving the problem]

[0006] The present invention is a deck installation method for installing precast concrete decks in sequence on a bridge girder, and includes an installation process for installing a trailing deck adjacent to a leading deck that has been installed earlier; a fastening process for fastening the leading deck and the trailing deck together with fastening members while a spacer is interposed in the gap between them; and a movement process for moving at least one of a transport cart that transports a deck other than the leading and trailing decks and a lifting cart that lifts the other deck, running over the leading and trailing decks. [Effects of the Invention]

[0007] According to the present invention, the work time required for erecting a deck can be reduced. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 10 is a schematic diagram for explaining deck renewal work. [Figure 2] FIG. 10 is a schematic diagram for explaining a deck erection method. [Figure 3] FIG. 3 is a diagram showing the state of the deck as viewed from the direction of arrow A in FIG. 2. [Figure 4] FIG. 4 is a cross-sectional view showing a cross section of the deck taken along line BB in FIG. 3. [Figure 5] FIG. 5 is a cross-sectional view taken along line CC in FIG. 4. [Figure 6A] 10A to 10C are diagrams for sequentially explaining the steps of erecting a deck slab. [Figure 6B] 6B is a diagram for explaining the steps of erecting a deck slab in order, showing a state following FIG. 6A. FIG. [Figure 6C] 6B is a diagram for explaining the steps of erecting the deck slab in order, showing the state following FIG. 6B. [Figure 6D] 6B is a diagram for explaining the steps of erecting the deck slab in order, showing the state following FIG. 6C. FIG. [Figure 7] FIG. 10 is a diagram showing a modified example of a fastening member for fastening the deck slabs together. [Figure 8] FIG. 10 is a diagram showing another modified example of a fastening member for fastening deck slabs together. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, a deck slab erection method according to an embodiment of the present invention will be described with reference to the drawings.

[0010] A deck erection method according to an embodiment of the present invention is a method for sequentially erecting new decks at locations where existing decks have been removed, for example, in deck renewal work to replace existing decks installed in bridges or tunnels with new decks.

[0011] First, the deck renewal work and the deck erection method according to an embodiment of the present invention will be described with reference to Figures 1 and 2. Figure 1 is an exaggerated image showing the deck renewal work on a bridge 1 for easy understanding, where (a) is a side view of the work site and (b) is a plan view of the work site. Figure 2 is an image showing the deck erection method for erecting a deck in the deck renewal work in the order of steps. Note that the devices and the like in these figures are shown simplified and at different scales from the actual ones.

[0012] As shown in Fig. 1(b), for example, bridge 1 has multiple main girders 4 (bridge girders) extending in the bridge axis direction, and multiple cross beams 5 provided between adjacent main girders 4, and as shown in Fig. 1(a), it is constructed by installing multiple deck slabs 2 along the longitudinal direction of bridge 1 so as to fill the gaps between adjacent main girders 4. As shown in Fig. 1(b), the main girders 4 are spanned between abutments (not shown) at predetermined intervals in the width direction of bridge 1.

[0013] The load of vehicles passing over bridge 1 is transmitted to main girders 4 via deck 2, which is mainly made of concrete or reinforced concrete. As a result, deck 2 gradually deteriorates or becomes damaged over time. Therefore, deck renewal work to replace deck 2 periodically is required.

[0014] In the deck renewal work, the existing deck slabs 2a are successively removed from above the main girders 4 by the removal lifting device 11 and transported away via the transport cart 12 and the transfer lifting device 13, while the new deck slabs 2b, brought in via the transfer lifting device 17 (lifting cart) and the transport cart 16, are successively installed on the main girders 4 by the installation lifting device 15 (lifting cart). In this way, in the deck renewal work, the work of removing the deck slabs and the work of installing the deck slabs proceed in parallel. In addition to these works, scraping work to remove rust and the like from the main girders 4 and height adjustment work to adjust the height of the main girders 4 also proceed in parallel.

[0015] To minimize the impact on traffic of ordinary vehicles, the periodic deck renewal work is carried out using the so-called half-section deck replacement method, which restricts traffic to only one lane 3a out of the multiple lanes 3a and 3b on the bridge 1. The area in which the deck 2 is renewed may be the entire bridge 1, or only a portion of it.

[0016] Next, with reference to FIG. 2, a deck erection method for installing new deck slabs 2b in order on the main girders 4 from which the existing deck slabs 2a have been removed will be described.

[0017] The installation lifting device 15 (lifting carriage) and the transport lifting device 17 (lifting carriage) used when installing the new deck slab 2b are so-called mobile gantry cranes equipped with a gantry frame and a traveling mechanism. The installation lifting device 15 is equipped with a lifting mechanism 15a capable of lifting the deck slab, a holder 15b that holds the lifting mechanism 15a, and multiple supports 15c that support the holder 15b. The transport lifting device 17 is equipped with a lifting mechanism 17a capable of lifting the deck slab, a holder 17b that holds the lifting mechanism 17a, and multiple supports 17c that support the holder 17b. In addition, a space is formed below the installation lifting device 15 to allow the transport carriage 16 to pass through in the longitudinal direction of the bridge 1 (the bridge axis direction), and a space is formed below the transport lifting device 17 to allow the transport carriage 16 and the transport vehicle 18 to pass through in the longitudinal direction of the bridge 1.

[0018] The transport vehicle 18 is a large truck that can travel on public roads and has a loading platform on which the new deck slab 2b can be placed and a driver's cab that is higher than the floor of the loading platform. The transport cart 16 is an electric unmanned cart that is used only at work sites and has a loading platform on which the new deck slab 2b can be placed.

[0019] In the deck erection method, as shown in Figure 2(a), first, a new deck slab 2b is carried into the work site by a transport vehicle 18. Specifically, the transport vehicle 18 moves forward to enter below the transport lifting device 17. Note that the transport vehicle 18 may move backward to enter below the transport lifting device 17, but because in order to back up a large truck, it is necessary to secure space to move forward by, for example, restricting traffic, it is preferable to move forward to enter below the transport lifting device 17.

[0020] The transport lifting device 17 lifts the new deck slab 2b placed on the transport vehicle 18, as shown in Figure 2(b), in order to transport the new deck slab 2b brought in by the transport vehicle 18 to the transport cart 16.

[0021] After lifting the new deck slab 2b to a predetermined height, the transport lifting device 17 moves to the left in the figure, as shown in Figure 2(c), to place the new deck slab 2b on the loading platform of the transport cart 16.

[0022] When the transport lifting device 17 reaches a position where the new deck slab 2b can be placed on the transport vehicle 16, it lowers the new deck slab 2b and places it on the loading platform of the transport vehicle 16, as shown in Figure 2(d). Meanwhile, the transport vehicle 18, which has handed over the new deck slab 2b to the transport lifting device 17, moves forward to the lane 3b where traffic is not restricted, and exits the work site.

[0023] After receiving the new deck slab 2b from the transfer lifting device 17, the transport vehicle 16 passes under the installation lifting device 15 and moves to below the lifting mechanism 15a of the installation lifting device 15, as shown in Figure 2(e), in order to hand over the new deck slab 2b to the installation lifting device 15. Meanwhile, the transfer lifting device 17, which has handed over the new deck slab 2b to the transport vehicle 16, moves to the right in the figure and waits until the next new deck slab 2b is brought in by the transport vehicle 18.

[0024] When the transport cart 16 reaches a predetermined position below the lifting mechanism 15a of the installation lifting device 15, the installation lifting device 15 lifts the new deck slab 2b, as shown in Figure 2(e), and then rotates to orient the new deck slab 2b so that it can be installed on the main girder 4.

[0025] The installation lifting device 15, which has lifted the new deck slab 2b from the transport vehicle 16, moves to the left in the figure as shown in Figure 2(f) in order to install the new deck slab 2b on the main girders 4, and then lifts down the new deck slab 2b and installs it on the main girders 4. Meanwhile, the transport vehicle 16, which has handed over the new deck slab 2b to the installation lifting device 15, moves to the right in the figure and waits at a predetermined position to receive the next new deck slab 2b from the transfer lifting device 17.

[0026] As described above, the installation lifting device 15 is moved from one end of the bridge 1 toward the other end, and the new deck slab 2b is installed one by one on the main girder 4 from which the existing deck slab 2a has been removed by the removal lifting device 11. The above-described process for transferring the new deck slab 2b to the installation lifting device 15 is one example, and for example, the new deck slab 2b may be transferred directly from the transport vehicle 18 to the installation lifting device 15 without using the transport cart 16 or the transfer lifting device 17.

[0027] Here, lifting carriages such as the installation lifting device 15 and transport lifting device 17 that lift the new deck slab 2b, and the transport carriage 16 that transports the new deck slab 2b, move on multiple new deck slabs 2b installed on the main girder 4, as shown in Figure 2, but at this point the new deck slabs 2b installed adjacent to each other in the bridge axis direction are not integrated, so if the load of the lifting carriages 15, 17 and the transport carriage 16 acts directly on the new deck slab 2b, it may cause the new deck slab 2b to bend in its longitudinal direction (the direction perpendicular to the bridge axis) and break. For this reason, steel materials such as rails are generally installed on the installed new deck slab 2b for the installation lifting device 15 and the like to run on.

[0028] However, the installation and removal of rails, etc. takes time, and the work of integrating adjacent new deck slabs 2b cannot be carried out until the removal of the rails, etc. is completed, making it difficult to shorten the work time required to erect the new deck slabs 2b and reducing work costs.

[0029] Therefore, in the above-described deck slab erection method, in order to shorten the work time required to erect the new deck slab 2b and reduce work costs, deck bodies 20 equipped with a fastening structure described below are sequentially installed as the new deck slab 2b, thereby enabling the lifting carts 15, 17 and the transport cart 16 to travel and move on the new deck slab 2b without providing rails for travel on the new deck slab 2b. More specifically, the lifting carts 15, 17 and the transport cart 16 can travel and move on the top surface of the new deck slab 2b without using rails or reinforcing steel materials such as H-beams or I-beams. Note that the gaps between the new deck slabs 2b may be simply covered with steel plates or the like, and the top surfaces of the covered portions may be used as a travel surface so that the lifting carts 15, 17 and the like can move on the new deck slabs 2b.

[0030] Next, the new deck slab 2b (deck slab body 20) used in the deck slab erection method according to this embodiment will be described with reference to Figures 3 to 6. Figure 3 is a diagram showing the state of multiple new deck slabs 2b as viewed from the direction of arrow A in Figure 2, Figure 4 is a cross-sectional view showing a cross section of the new deck slab 2b (deck slab body 20) taken along line BB in Figure 3, and Figure 5 is a cross-sectional view showing a cross section taken along line CC in Figure 4. Figures 6A to 6D sequentially show diagrams for explaining the process of erecting the new deck slab 2b (deck slab body 20) shown in Figures 3 to 5.

[0031] The new slab 2b is a flat, precast concrete slab body 20, which is installed so that the longitudinal direction of the slab body 20 is perpendicular to the bridge axis direction, as shown in Figure 3, and the "following slab" installed adjacent to the previously installed "leading slab" is fastened to the "leading slab" via fastening members 30. Note that although the multiple new slabs 2b shown in Figure 3 are not completely fixed to each other in the bridge axis direction, as will be described later, by fastening them to each other via spacers 40 with fastening members 30, their upper surfaces can be used, for example, as running surfaces for lifting carts 15, 17 and transport carts 16.

[0032] In Figure 3, the deck body 20 designated by the symbol 20A is a "leading deck body" installed ahead of the deck body 20 designated by the symbol 20B, and in this case, the deck body 20 designated by the symbol 20B is a "following deck body" installed after the deck body 20 designated by the symbol 20A. On the other hand, the deck body 20 designated by the symbol 20B is a "leading deck body" installed ahead of the deck body 20 designated by the symbol 20C, and in this case, the deck body 20 designated by the symbol 20C is a "following deck body" installed after the deck body 20 designated by the symbol 20B. Note that Figure 3 shows a state in which another new deck slab 2b has not yet been installed after the deck body 20 designated by the symbol 20C has been installed.

[0033] As shown in Figure 3, each deck body 20 has a plurality of first recesses 21 provided on the leading deck body side and a plurality of second recesses 22 provided on the trailing deck body side, and the fastening members 30 that fasten two adjacent deck bodies 20 are arranged so that one end protrudes into the first recess 21 formed in one deck body 20 and the other end protrudes into the second recess 22 formed in the other deck body 20.

[0034] As shown in Figure 4, the first recess 21 and the second recess 22 are recesses that open to the top surface of the deck body 20 and have a predetermined depth, and are provided at the same position in the longitudinal direction of the deck body 20, as shown in Figure 3. In other words, in two adjacent deck bodies 20, the first recess 21 formed in one deck body 20 and the second recess 22 formed in the other deck body 20 are positioned opposite each other. In the example shown in Figure 3, four first recesses 21 and four second recesses 22 are provided along the longitudinal direction of the deck body 20, but the number of first recesses 21 and second recesses 22 provided is not limited to this.

[0035] In addition, the wall-like portion formed between the first recess 21 and the end face of the leading deck slab due to the formation of the first recess 21, and the wall-like portion formed between the second recess 22 and the end face of the trailing deck slab due to the formation of the second recess 22, function as connecting flanges when fastening two adjacent deck slab bodies 20 together with the fastening member 30, as shown in Figure 4.

[0036] Each deck slab body 20 is provided with a first through hole 21a formed penetrating from the first recess 21 toward the leading deck slab side, a bottomed accommodation hole 21b formed coaxially with the first through hole 21a from the first recess 21 toward the opposite side from the leading deck slab side, and a second through hole 22a formed penetrating from the second recess 22 toward the trailing deck slab side. These first through hole 21a and second through hole 22a are used as insertion holes through which members constituting the fastening member 30 are inserted, as described below.

[0037] The fastening member 30 is mainly composed of a double-threaded bolt 31 (long shaft member) with threads on both ends, a pair of nuts 32 attached to both ends of the double-threaded bolt 31, a support plate 33 that functions as a washer for the nuts 32, and a resin sheath tube 35 through which the double-threaded bolt 31 is inserted.

[0038] 4 shows a state in which both threaded bolts 31 and sheath tubes 35 are arranged so as to pass through the first through hole 21a of one of two adjacent deck slab bodies 20 and the second through hole 22a of the other, and nuts 32 are fastened to both ends of both threaded bolts 31 via support plates 33. In this manner, when two adjacent deck slab bodies 20 are fastened together by the fastening members 30, the fastening members 30 are provided across the two adjacent deck slab bodies 20. Before fastening the two deck slab bodies 20 together, one end of the fastening member 30 is inserted into the receiving hole 21b, and the other end is accommodated inside the deck slab body 20 so as not to protrude outward from the end face of the deck slab body 20, as shown in FIG. 6A described below.

[0039] Furthermore, as shown in Figure 4, two adjacent deck bodies 20 are fastened together by a fastening member 30 of the above-described configuration with a gap G1 of a predetermined size (for example, around 10 mm, preferably 8 to 15 mm) provided between the opposing end faces, and with a spacer 40 interposed in this gap G1.

[0040] The spacers 40 are plate-like members made of a material with a smaller elastic modulus than the deck body 20, such as plywood, concrete panels, or hard rubber material, and are preferably made of wood or resin materials (rubber, plastic), etc. As shown in Fig. 5, the spacers 40 are provided in a range such that, for example, the length in the longitudinal direction of the deck body 20 exceeds the length of the first recesses 21 and the second recesses 22, and the length in the up-down direction of the deck body 20 exceeds the depth of the first recesses 21 and the second recesses 22, and the upper end is positioned flush with the upper surface of the deck body 20 or protrudes upward by a predetermined length (for example, about several mm to 10 mm) above the upper surface of the deck body 20.

[0041] The spacer 40 also has a notch 40a cut out in an inverted U shape from the bottom end upward. The notch 40a is formed in a location corresponding to the location where the fastening member 30 is to be provided, and the provision of the notch 40a makes it possible to insert the spacer 40 into the gap G1 from above even when the fastening member 30 is bridged between two adjacent deck bodies 20.

[0042] Furthermore, the thickness of the spacer 40 is several millimeters thicker before it is sandwiched between the two deck bodies 20 than after it is sandwiched between them. In other words, the thickness of the spacer 40 before it is sandwiched is set to be larger than the gap G1.

[0043] For this reason, the spacer 40 is sandwiched in a compressed state between the two deck bodies 20 fastened with the fastening members 30, with at least a portion of the spacer 40 located above the fastening members 30, i.e., closer to the upper surface of the deck body 20 than the fastening members 30. In other words, fastening with the fastening members 30 means that the two deck bodies 20 are connected so that the spacer 40 is compressed and sandwiched between them, and the fastening members 30 also function as connecting members that connect the two deck bodies 20.

[0044] The spacer 40 may be made of any material as long as it has a smaller elastic modulus than the deck body 20 made of precast concrete. However, it is preferable that the elastic modulus is about half that of precast concrete, for example, 7000 to 12000 N / mm 2 It is preferable that the material be of a similar quality.

[0045] Next, each step of the deck erection method according to this embodiment will be described with reference to Figures 6A to 6D. In the following description, the deck body 20 designated by the reference symbol 20A will be referred to as the leading deck body 20A, and the deck body 20 designated by the reference symbol 20B will be referred to as the trailing deck body 20B.

[0046] In the deck erection method, first, as shown in FIG. 6A, the trailing deck slab 20B is installed adjacent to the leading deck slab 20A that has been installed on the main girder 4 first (installation step).

[0047] Specifically, the trailing deck 20B, which is lifted by the installation lifting device 15 (see (f) of Figure 2), is installed on the main girder 4 so as to be close to the leading deck 20A, which was previously installed on the main girder 4.

[0048] In the installation process, as described above, one end of each fastening member 30 is inserted into the receiving hole 21b, and the other end is accommodated inside the trailing deck 20B so as not to protrude outward from the end face of the trailing deck 20B. In this way, since there are no members protruding from the trailing deck 20B toward the leading deck 20A, the trailing deck 20B can be easily installed near the leading deck 20A.

[0049] Furthermore, because the deck body 20 does not have any components that protrude in the width direction when it is transported or conveyed, it is possible to increase the width of the deck body 20 itself, for example, to the width that is limited during transportation, compared to conventional cases where joint rebars protrude in the width direction of the deck. This makes it possible to reduce the number of new deck slabs 2b to be installed, which in turn reduces the cost of the deck renewal work.

[0050] After the trailing deck 20B is installed adjacent to the leading deck 20A, the leading deck 20A and the trailing deck 20B are then fastened together by fastening members 30 with a spacer 40 interposed in the gap G1 between the leading deck 20A and the trailing deck 20B, as shown in Figure 6B (fastening process).

[0051] Specifically, first, a sheath tube 35 is inserted into the second through hole 22a of the preceding deck slab 20A to protect the threaded portions of both threaded bolts 31 on the preceding deck slab side, and then both threaded bolts 31, which were partially housed in the housing hole 21b, are inserted through the sheath tube 35 into the second through hole 22a.

[0052] Next, the spacer 40 is inserted from above into the gap G1 between the leading deck slab 20A and the trailing deck slab 20B. The insertion of the spacer 40 is restricted by the upper end of the cutout portion 40a abutting against the sheath tube 35. In other words, the position of the spacer 40 is determined by the cutout portion 40a and the sheath tube 35.

[0053] Then, nuts 32 are tightened to both ends of both threaded bolts 31 via bearing plates 33, so that the leading deck slab 20A and the trailing deck slab 20B are fastened together with a spacer 40 interposed in the gap G1, as shown in Fig. 6B. In other words, the spacer 40, which has a smaller elastic modulus than the leading deck slab 20A and the trailing deck slab 20B, is sandwiched between the leading deck slab 20A and the trailing deck slab 20B in a state where it is slightly compressed in the fastening direction.

[0054] By fastening the leading deck slab 20A and the trailing deck slab 20B together with the spacer 40 interposed in this manner, the above-mentioned lifting carriages 15, 17 and transport carriage 16 can travel on the leading deck slab 20A and the trailing deck slab 20B, and for example, the upper surfaces of the leading deck slab 20A and the trailing deck slab 20B become running surfaces on which the wheels of the above-mentioned lifting carriages 15, 17 and transport carriage 16 can travel in direct contact without using running rails. Note that the upper surface of the portion where the gap between the leading deck slab 20A and the trailing deck slab 20B is simply covered with a steel plate or the like may be used as a running surface on which the above-mentioned lifting carriages 15, 17 and transport carriage 16 travel, and they may move on the leading deck slab 20A and the trailing deck slab 20B.

[0055] Here, for example, if the load of the installation lifting device 15 that lifts the new deck slab 2b acts near the connection between the leading deck slab 20A and the trailing deck slab 20B via the wheels of the installation lifting device 15, a load that brings the leading deck slab 20A and the trailing deck slab 20B closer together, i.e., a compressive load along the bridge axis direction, will act near the upper part of the connection, while a load that pulls the leading deck slab 20A and the trailing deck slab 20B apart, i.e., a tensile load along the bridge axis direction will act near the lower part of the connection.

[0056] If a load is applied that brings the leading deck slab 20A and the trailing deck slab 20B closer to each other, there is a risk that cracks or chips will occur in the leading deck slab 20A and the trailing deck slab 20B, but as described above, the spacers 40 are provided at the connection between the leading deck slab 20A and the trailing deck slab 20B so that the positions of their upper ends are approximately flush with the upper surfaces of the leading deck slab 20A and the trailing deck slab 20B, thereby preventing the leading deck slab 20A and the trailing deck slab 20B from directly interfering with each other. In addition, because the elastic modulus of the spacers 40 is smaller than that of the deck body 20, cracks or chips will be prevented from occurring at the ends of the leading deck slab 20A and the trailing deck slab 20B that are pressed against the spacers 40 due to the spacers 40 deforming first.

[0057] In addition, the tensile load acting to pull the leading deck slab 20A and the trailing deck slab 20B apart from each other is absorbed by both threaded bolts 31 via the support plate 33 and the nut 32, thereby preventing the leading deck slab 20A and the trailing deck slab 20B from becoming too far apart near the lower part of the connection, and as a result, preventing the leading deck slab 20A and the trailing deck slab 20B from being deformed by the load of the installation lifting device 15.

[0058] Furthermore, for example, if the load of the installation lifting device 15 that lifts the new deck slab 2b acts on either the leading deck slab 20A or the trailing deck slab 20B via the wheels of the installation lifting device 15, a shear force will be generated between the leading deck slab 20A and the trailing deck slab 20B. However, because the leading deck slab 20A and the trailing deck slab 20B sandwich the spacer 40 in a compressed state, the frictional force generated between the leading deck slab 20A and the spacer 40 and the frictional force generated between the trailing deck slab 20B and the spacer 40 act as resistance forces that counteract the shear force, preventing the leading deck slab 20A and the trailing deck slab 20B from shifting up and down at the connection. Note that the fastening member 30 that fastens the leading deck slab 20A and the trailing deck slab 20B also generates a shear stress that counteracts the shear force.

[0059] In this way, by adopting the above-described fastening structure, deformation and damage that are expected to occur when the loads of the lifting carriages 15, 17 and the transport carriage 16 act directly on the leading deck slab 20A and the trailing deck slab 20B are prevented, and the upper surfaces of the leading deck slab 20A and the trailing deck slab 20B can be used as running surfaces for the lifting carriages 15, 17 and the transport carriage 16. Note that the gap between the leading deck slab 20A and the trailing deck slab 20B may be partially cured by covering it with an iron plate or the like, and the upper surface of the cured portion may be used as the running surface.

[0060] The running surface is set along the bridge axis direction, for example, as shown by symbol S1 in Figure 3, avoiding the location where the leading deck slab 20A and the trailing deck slab 20B are fastened by the fastening member 30, i.e., the location where the first recess 21 and the second recess 22 are formed.

[0061] In this way, with the spacer 40 interposed in the gap G1 between the leading deck slab 20A and the trailing deck slab 20B, the leading deck slab 20A and the trailing deck slab 20B are fastened together by the fastening member 30, thereby enabling the lifting carts 15, 17 and the transport cart 16 to move.The transport cart 16 transporting the new deck slab 2b to be installed on the main girder 4, i.e., a deck body 20 different from the leading deck slab 20A and the trailing deck slab 20B already installed on the main girder 4, and the lifting carts 15, 17 lifting the new deck slab 2b, move using the upper surfaces of the leading deck slab 20A and the trailing deck slab 20B as their running surfaces S1 (movement process).

[0062] As described above, compared to the case where rails or the like are installed on the leading deck slab 20A and the trailing deck slab 20B for the lifting carriages 15, 17 and the transport carriage 16 to travel on, in this embodiment, it is not necessary to install such rails or the like. Therefore, since the installation work of rails or the like and the removal work of rails or the like are not necessary, it is possible to shorten the work time required to erect the new deck slab 2b and reduce the work costs required to erect the new deck slab 2b.

[0063] As the erection work for the new slab 2b progresses further and the upper surfaces of the leading slab 20A and the trailing slab 20B are no longer used as the running surface S1, work begins to integrate the leading slab 20A and the trailing slab 20B in the bridge axis direction. The state in which the upper surfaces of the leading slab 20A and the trailing slab 20B are no longer used as the running surface S1 means that, as the erection work for the new slab 2b progresses, the leading slab 20A and the trailing slab 20B are no longer within the movement range of the lifting carts 15, 17 and the transport cart 16, as in the case of the new slab 2b installed to the right of the transfer lifting device 17 shown in FIG. 2(f). Specifically, the work to integrate the leading slab 20A and the trailing slab 20B is performed at a position at least 20 m, more preferably at least 40 m, away from the most advanced new slab 2b, i.e., the most recently installed new slab 2b.

[0064] In the work of integrating the leading deck 20A and the trailing deck 20B, which is carried out after the moving step, first, as shown in Figure 6C, the spacers 40 are removed from the gap G1 (removal step), and then, as shown in Figure 6D, mortar is filled as a filler into the gap G1, the first recess 21, and the second recess 22. Note that the filler may be filled in the gap G1 with the spacers 40 remaining in place (filling step).

[0065] In the removal process, the nuts 32 of the fastening members 30 that fasten the leading deck slab 20A and the trailing deck slab 20B together are loosened to reduce the fastening force, and then the spacers 40 are pulled upward from the gap G1. Note that if the fastening force of the fastening members 30 does not decrease significantly, the spacers 40 may be crushed and removed.

[0066] After the spacer 40 is removed from the gap G1, in the filling step, first, mortar is filled only in the gap G1 by the first filling F1. Then, when the mortar filled in the gap G1 has hardened to a certain extent, the nuts 32 of the fastening member 30 that were loosened in the removal step are tightened. As described above, the double-threaded bolts 31 of the fastening member 30 are inserted into the sheath tube 35, which is configured to be less likely to come into contact with the mortar filled in the gap G1. This makes it easy to tighten the nuts 32 on the double-threaded bolts 31. Note that, in order to prevent the double-threaded bolts 31 from coming into contact with the mortar, the sheath tube 35 may be filled in advance with a resin material or the like. Note that, without removing the spacer 40 from the gap G1, mortar may be filled only in the space of the gap G1 where the spacer 40 is not present.

[0067] In the filling step, once filling of mortar into the gap G1 (first filling F1) is completed and tightening of the nut 32 is completed, mortar is subsequently filled into the first recess 21 and the second recess 22 by second filling F2.

[0068] The filler used in the filling step is not limited to mortar, and may be, for example, a cement-based solidification material such as concrete or cement paste. Furthermore, the nut 32 of the fastening member 30 may be pre-threaded into a predetermined position on the double-threaded bolt 31 before filling the gap G1 so that the size of the gap G1 is a predetermined size, without being tightened after filling the gap G1.

[0069] After the curing period for the mortar or other filler material filled in during the filling process has elapsed, and the leading deck 20A and the trailing deck 20B are integrated in the bridge axis direction, the leading deck 20A and the trailing deck 20B are ready to have a roadway paved on their upper surfaces. This completes the series of steps for erecting the new deck 2b.

[0070] According to the above embodiment, the following advantageous effects are achieved.

[0071] In the deck erection method of this embodiment, the transport vehicle 16 that transports the new deck slab 2b and the lifting vehicles 15, 17 that lift the new deck slab 2b travel and move on the leading deck slab 20A and the trailing deck slab 20B that are fastened via spacers 40. More specifically, they travel using the upper surfaces of the leading deck slab 20A and the trailing deck slab 20B as the travel surface S1.

[0072] In this way, there is no longer a need to provide rails or the like on the upper surfaces of the leading deck slab 20A and the trailing deck slab 20B for running the transport cart 16 and the lifting carts 15, 17, which shortens the work time required to erect the new deck slab 2b and reduces the work costs required to erect the new deck slab 2b. In addition, work to integrate the leading deck slab 20A and the trailing deck slab 20B in the bridge axis direction can be started without waiting for the rails or the like to be removed, which further shortens the work time required to erect the new deck slab 2b.

[0073] Furthermore, the integration of the leading deck 20A and the following deck 20B can be achieved simply by filling the relatively narrow gap G1 with a filler such as mortar, eliminating the need to install formwork, connect rebar, or pour concrete in the pouring area formed between the leading and following decks, as was previously required, thereby significantly reducing the work time required to erect the new deck 2b. Furthermore, by using an inorganic hardener such as mortar or a cement-based hardener in the integration of the leading deck 20A and the following deck 20B, the resistance of the entire deck to deterioration over time can be improved.

[0074] The following modified examples are also within the scope of the present invention, and it is possible to combine the configuration shown in the modified example with the configuration described in the above embodiment, or to combine the configurations described in the different modified examples below.

[0075] In the above embodiment, the first recess 21 is provided with a receiving hole 21b for receiving the fastening member 30. Alternatively, as in the fastening member 130 of a first modified example shown in FIG. 7, the double-threaded bolt (long shaft member) may be divided into two members, a first bolt portion 131a on the leading deck slab 20A side and a second bolt portion 131b on the trailing deck slab 20B side, and the fastening member 130 may be configured to be received in each of the leading deck slab 20A and the trailing deck slab 20B, thereby eliminating the need to form a receiving hole. In the first modified example shown in FIG. 7, the first bolt portion 131a and the second bolt portion 131b are integrated into a long shaft member by threading one end of the second bolt portion 131b into a female thread socket portion formed at the end of the first bolt portion 131a.

[0076] Furthermore, in the above embodiment, the first recess 21 and the second recess 22 in which the fastening member 30 is provided are open on the upper surface of the deck body 20. Alternatively, as in the first recess 121 and the second recess 122 of the first modified example shown in Fig. 7, the first recess 121 and the second recess 122 in which the fastening member 130 is provided may be open on the lower surface of the deck body 20. In this case, it is possible to set the running surface S1 on the upper surfaces of the leading deck slab 20A and the following deck slab 20B without avoiding the locations where the first recess 121 and the second recess 122 are formed.

[0077] Moreover, in the above embodiment, a double-threaded bolt 31 and a nut 32 are used as the fastening member 30. The fastening member is not limited to this, and may have any structure as long as it is provided across the leading deck slab 20A and the trailing deck slab 20B and is capable of fastening the leading deck slab 20A and the trailing deck slab 20B together. For example, like the fastening member 230 of the second modified example shown in Fig. 8, it may be a single member that has a rod-shaped or plate-shaped connecting portion 231a and flange portions 231b provided on both ends of the connecting portion 231a, and is provided across the leading deck slab 20A and the trailing deck slab 20B to be able to fasten the leading deck slab 20A and the trailing deck slab 20B together. In the second modified example shown in Figure 8, the connecting portion 231a is inserted into the U-shaped grooves 121a, 122a formed in the first recess 21 and the second recess 22, and the leading deck slab 20A and the trailing deck slab 20B are fastened together by a wedge effect created by the contact between the tapered surfaces of each flange portion 231b and the tapered surfaces of the first recess 21 and the second recess 22.

[0078] Furthermore, in the above embodiment, the deck erection method has been described as a method for sequentially erecting new decks at locations where existing decks have been removed during deck renewal work, but the deck erection method is not limited to methods used in deck renewal work, and may also be used as a method for erecting new decks, for example, by extending new main girders along the bridge axis or tunnel axis direction and then sequentially erecting new precast concrete decks on the main girders.

[0079] In the above embodiment, the spacer 40 has a notch 40a cut in an inverted U-shape from the lower end upward. Alternatively, the spacer 40 may simply have a plurality of through holes through which the fastening members 30 are inserted, without the inverted U-shaped notch 40a. The spacer 40 may also have a U-shaped notch cut from the upper end downward. By ensuring an area of ​​the spacer 40 that is sandwiched between the two deck bodies 20 below the fastening members 30 in this manner, the spacer 40 can prevent the two deck bodies 20 from directly interfering with each other below the fastening members 30, for example, when a load acting on the deck bodies 20 when the lifting carts 15, 17 travels causes a load that brings the two deck bodies 20 closer together below the fastening members 30, i.e., a compressive load along the bridge axis.

[0080] Although the embodiments of the present invention have been described above, the above embodiments merely illustrate some of the application examples of the present invention, and it is not intended that the technical scope of the present invention be limited to the specific configurations of the above embodiments. [Explanation of symbols]

[0081] 1. Bridge 2b Newly constructed deck (slab) 4. Main girder (bridge girder) 15... Lifting device for installation (lifting trolley) 16. Transport vehicle 17... Lifting device for transportation (lifting trolley) 20...Floor slab (floor slab) 20A...Advanced floor slab (floor slab) 20B... Trailing floor slab (floor slab) 21,121···First recess 22,122···Second recess 30, 130, 230... Fastening members 31. Double-threaded bolt (long shaft member) 40...Spacer G1: Gap S1 Running surface

Claims

1. A deck erection method in which precast concrete decks are installed in order on a bridge girder, an installation process of installing a trailing deck adjacent to the previously installed leading deck; a fastening step of fastening the leading deck slab and the trailing deck slab together with fastening members while a spacer is interposed in the gap between the leading deck slab and the trailing deck slab; and a moving process in which at least one of a transport vehicle that transports a floor slab other than the preceding floor slab and the following floor slab, and a lifting vehicle that lifts the other floor slab, travels and moves on the preceding floor slab and the following floor slab. Floor slab erection method.

2. The method further includes a filling step of filling the gap with a filler, The filling step is performed after the moving step. A deck erection method according to claim 1.

3. a removing step of removing the spacer from the gap; and a filling step of filling the gap with a filler, The removing step and the filling step are performed after the moving step. A deck erection method according to claim 1.

4. The elastic modulus of the spacer is smaller than the elastic modulus of the preceding floor slab and the following floor slab, A deck erection method according to any one of claims 1 to 3.

5. The fastening member is a long shaft member arranged along the bridge axis direction so that one end protrudes into a first recess formed in the preceding deck slab and the other end protrudes into a second recess formed in the following deck slab. A deck erection method according to any one of claims 1 to 3.

6. The fastening member is provided across the leading floor slab and the trailing floor slab, The spacer is provided so that at least a portion thereof is located above the fastening member. A deck erection method according to any one of claims 1 to 3.

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