JP7712225B2 - Guard fences, guard fence installation methods, and deck replacement methods - Google Patents

Description

The present invention relates to a guard fence, a guard fence installation method, and a deck replacement construction method.

Technology has been proposed to replace the existing deck that forms the road of a bridge with a new deck. Even during construction work to replace the deck of some lanes of the road, it is desirable to keep the other lanes of the road in service for vehicle traffic. For this reason, for example, Patent Document 1 discloses technology in which temporary protective fences are installed on the road to separate the lanes where construction work to replace the existing deck is being carried out from the lanes in service for vehicle traffic.

JP 2018-9396 A

The above technology discloses the installation of a temporary protective fence to prevent vehicles from leaving the lane, so that deck replacement work can be carried out safely in other lanes (lane A) while some lanes (lane B) remain in service. In order to install a temporary protective fence strong enough to withstand the impact of a vehicle leaving the lane, it is necessary to restrict traffic and close the lane. As a result, the traffic restriction period required to install the protective fence is long.

The present invention aims to provide a guardrail, a guardrail installation method, and a deck replacement method that can shorten the traffic control period required to install the guardrail.

The present invention is a guardrail that divides a road formed by a deck, and is provided with a deck, a guardrail section that divides the road, a deck through-hole section that passes through the deck from top to bottom, and a fixing member that is inserted into the deck through-hole section and fixes the guardrail section to the deck.

According to this configuration, the guardrail that divides the road formed by the deck comprises the deck, a guardrail section that divides the road, a deck through-hole section that penetrates the deck from top to bottom, and a fixing member that is inserted into the deck through-hole section and fixes the guardrail section to the deck. The guardrail section is fixed to the deck by the fixing member that is inserted into the deck through-hole section that penetrates the deck from top to bottom and fixes the guardrail section to the deck. Compared to conventional technology in which a temporary guardrail is fixed to the deck by anchors driven into the top surface of the deck, more of the work required to fix the guardrail section to the deck can be done from the underside of the deck. Therefore, the traffic restriction period required to install the guardrail can be shortened.

In this case, the deck has multiple precast decks arranged at intervals in the direction of travel of the road, and filler concrete poured on-site between the multiple precast decks, and the deck through-holes may be formed in the filler concrete.

According to this configuration, in a deck having multiple precast decks arranged at intervals in the direction of travel of the road and infill concrete poured on-site between the multiple precast decks, the deck through-holes are formed in the infill concrete, and no holes are provided in the precast decks that mainly constitute the deck, improving the durability of the deck.

The present invention also provides a method for installing a guardrail that divides a road formed by a deck, the method including a deck through hole forming step for forming a deck through hole that penetrates the deck from top to bottom, and a guardrail fixing step for placing a guardrail that divides the road on the deck and fixing the guardrail to the deck with a fixing member inserted through the deck through hole formed in the deck through hole forming step.

In this case, the deck is newly constructed to replace the existing one, and includes multiple precast decks arranged at intervals in the direction of road travel and filler concrete poured on-site between the multiple precast decks, and further includes a new deck construction process in which, after arranging the multiple precast decks at intervals in the direction of road travel to replace the existing ones, the filler concrete is poured on-site between the multiple precast decks, and in the deck through hole formation process, a deck through hole may be formed in the filler concrete when the filler concrete is poured on-site in the new deck construction process.

According to this configuration, in the new slab construction process, multiple precast slabs are arranged in a line with spaces between them in the direction of travel of the road to replace the existing ones, and then filler concrete is poured on-site between the multiple precast slabs. In the slab through-hole formation process, when the filler concrete is poured on-site in the new slab construction process, a slab through-hole is formed in the filler concrete. This allows the pouring of the filler concrete on-site and the formation of the slab through-hole to be performed simultaneously, making it easier to form the slab through-hole.

The fixing member may also be composed of a rod protruding below the protective fence section and a fastening member that fits into the rod, and in the protective fence section fixing process, the protective fence section may be placed on the deck slab while the rod is inserted into the deck slab through-hole section formed in the deck slab through-hole section forming process, and the protective fence section may be fixed to the deck slab by fitting the fastening member into the rod inserted into the deck slab through-hole section.

According to this configuration, the fixing member is composed of a rod protruding below the guardrail section and a fastening member that fits into the rod, and in the guardrail section fixing process, the rod is inserted into the deck through hole formed in the deck through hole forming process, and the guardrail section is placed on the deck. Therefore, immediately after the guardrail section is placed on the deck, it is placed on the deck so that it does not shift laterally. Also, in the guardrail section fixing process, the fastening member is fitted into the rod inserted into the deck through hole, and the guardrail section is fixed to the deck. Therefore, in the guardrail section fixing process, much more of the work required to fix the guardrail section to the deck can be done from the underside of the deck. This makes it possible to shorten the traffic control period required to install the guardrail.

The present invention also relates to a deck replacement method for replacing a deck on a road having multiple lanes, the method including: an existing deck through hole forming process for forming an existing deck through hole portion that penetrates vertically through the existing deck in some of the multiple lanes; an existing deck protective fence portion fixing process for arranging a protective fence portion that divides some of the lanes on the existing deck in which the existing deck through hole portion was formed in the existing deck through hole portion forming process and fixing the protective fence portion to the existing deck with a fixing member inserted through the existing deck through hole portion; a first existing deck protective fence portion removal process for removing the existing deck in other lanes except for some of the lanes of the existing deck to which the protective fence portion was fixed in the existing deck protective fence portion fixing process; and a first new deck installation process for arranging multiple precast decks in the other lanes from which the existing deck was removed in the first existing deck removal process.

With this configuration, after the existing deck through-hole forming process and existing deck protective fence fixing process, which shorten the traffic control period, a first existing deck removal process is carried out to remove the existing deck in the other lanes while leaving some of the lanes divided by the protective fence for vehicle traffic, and a first new deck construction process is carried out to place precast decks in the other lanes, thereby extending the period during which the road can be used for vehicle traffic.

In this case, in the first new deck construction process, multiple precast decks are arranged with spaces between them in the direction of travel of the other lane, and then filler concrete is poured on-site between the multiple precast decks. When pouring the filler concrete on-site, a filler concrete through-hole is formed that penetrates the filler concrete from top to bottom. In the existing deck protective fence part fixing process, the fixation by the fixing members between the protective fence part fixed to the existing deck and the existing deck is released, and in the new deck construction process, the filler concrete with the filler concrete through-hole formed and the multiple The method may further include a new deck slab guard fence section fixing process in which the guard fence section is moved and placed on the precast deck slab, and the guard fence section is fixed to the concrete filler and the multiple precast deck slabs by a fixing member inserted into the concrete filler through hole formed in the new deck slab installation process, a second existing deck slab removal process in which the existing deck slabs in some lanes are removed after the new deck slab guard fence section fixing process, and a second existing deck slab new installation process in which multiple precast deck slabs are placed in some lanes from which the existing deck slabs were removed in the second existing deck slab removal process.

According to this configuration, in the new deck slab protective fence section fixing process, the fixing member between the protective fence section fixed to the existing deck slab in the existing deck slab protective fence section fixing process and the existing deck slab is released, and the protective fence section is moved and positioned to the fill concrete and multiple precast deck slabs in which the fill concrete penetration hole section is formed in the new deck slab construction process, and the protective fence section is fixed to the fill concrete and multiple precast deck slabs by the fixing member inserted into the fill concrete penetration hole section formed in the new deck slab construction process, so that the traffic control period required to move the protective fence section from the existing deck slab and then install it on the precast deck slab can be shortened.

In addition, after the process of fixing the new deck guardrail, which shortens the traffic restriction period, a second process of removing the existing deck in some lanes will be carried out, in which the existing deck in some lanes will be removed while the other lanes separated by the guardrail are kept open for vehicle traffic, and a second process of installing precast deck in some lanes will be carried out, which will extend the period during which the road can be used for vehicle traffic.

The present invention also relates to a guardrail that divides a road formed by a deck, the guardrail having a first guardrail section that extends along the lane of the road divided by the guardrail, and a second guardrail section that extends along the lane and is continuous with the first guardrail section, the connection section that connects the first guardrail section and the second guardrail section has a convex section on one side and a concave section on the other side when viewed vertically, and the convex section and the concave section are interlocking with each other.

According to this configuration, in a guardrail that divides a road formed by a deck, the guardrail comprises a first guardrail section that extends along the lane of the road divided by the guardrail, and a second guardrail section that extends along the lane and is continuous with the first guardrail section. The connection section that connects the first guardrail section and the second guardrail section has a convex section on one side and a concave section on the other side when viewed vertically, and the convex section and the concave section can be fitted together, so that it is easy to connect the first guardrail section and the second guardrail section, and the traffic control period required to install the guardrail can be shortened.

In this case, it is preferable that the convex and concave portions have locking portions that limit movement in the direction along the lane.

With this configuration, the convex and concave portions have locking sections that limit movement along the lane, making it easy to connect the first and second protective fence sections, and shortening the traffic restriction period required to install the protective fence.

It is also preferable to further include a deck through-hole portion that penetrates the deck from top to bottom, and a fixing member that consists of a rod material that protrudes below the first and second protective fence portions, is inserted into the deck through-hole portion, and fixes the first and second protective fence portions to the deck.

According to this configuration, the first and second protective fence sections are fixed to the deck by fixing members that are inserted into deck through-holes that penetrate the deck from top to bottom and fix the first and second protective fence sections to the deck. Compared to conventional technology in which a temporary protective fence is fixed to the deck by anchors driven into the top surface of the deck, more of the work required to fix the protective fence sections to the deck can be done from the underside of the deck. This means that the traffic restriction period required to install the protective fence can be shortened.

The present invention also provides a method for installing a guardrail that divides a road formed by a deck, the method comprising a first guardrail section installation step of installing a first guardrail section so as to extend along the lane of the road divided by the guardrail, and a second guardrail section installation step of installing a second guardrail section so as to extend along the lane, continuous with the first guardrail section, in which in the first guardrail section installation step and the second guardrail section installation step, a connection section that connects the first guardrail section and the second guardrail section has a convex section on one side and a concave section on the other side when viewed vertically, and the convex section and the concave section are interlocking with each other.

In this case, in the first protective fence section installation process and the second protective fence section installation process, it is preferable to install the first protective fence section and the second protective fence section in the convex section and the concave section, which have a locking section that limits movement in the direction along the lane.

In addition, in the first protective fence section installation process, a first protective fence section consisting of a rod protruding below the first protective fence section and having a fixing member for fixing the first protective fence section to the deck slab is installed on a deck slab having a deck slab through-hole section that penetrates the deck slab vertically, while inserting the rod into the deck slab through-hole section, and in the second protective fence section installation process, a second protective fence section consisting of a rod protruding below the second protective fence section and having a fixing member for fixing the second protective fence section to the deck slab is installed on a deck slab having a deck slab through-hole section, while inserting the rod into the deck slab through-hole section.

The guard fence, guard fence installation method, and deck replacement method of the present invention can shorten the traffic control period required to fix the guard fence.

1A, 1B, 1C, 1D, 1E and 1F are longitudinal cross-sectional views perpendicular to the road travel direction, showing each process of the deck replacement construction method according to the first embodiment. (A) is a plan view showing the protective fence of the first embodiment in which the protective fence section is fixed to an existing deck slab, (B) is a cross-sectional view taken along the alpha line of (A), and (C) is a cross-sectional view taken along the beta line of (A). 1A, 1B, 1C, 1D, 1E, 1F and 1G are longitudinal cross-sectional views perpendicular to the road travel direction, showing each process after FIG. 1F of the deck replacement construction method according to the first embodiment. (A) is a plan view showing the first embodiment of the protective fence in which the protective fence section is fixed to a newly constructed precast deck, (B) is a cross-sectional view of (A) taken by gamma rays, and (C) is a cross-sectional view of (A) taken by delta rays. (A) is a plan view showing a protective fence of the first embodiment in which a protective fence section is fixed to a newly constructed precast deck slab in a manner different from that of Figures 4 (A), 4 (B), and 4 (C), and (B) is a cross-sectional view along the ε line of (A). (A) is a plan view showing a protective fence of the first embodiment in which a protective fence section is fixed to a newly constructed precast deck slab in a manner different from that shown in Figures 4(A), 4(B), 4(C), 5(A) and 5(B), and (B) is a cross-sectional view taken along line ζ of (A). (A) is a plan view showing a protective fence of the second embodiment in which a protective fence section is fixed to a newly constructed precast deck slab, (B) is a cross-sectional view taken along line η of (A), and (C) is a cross-sectional view taken along line θ of (A). (A) is a plan view showing a protective fence according to the third embodiment in which a protective fence section is fixed to a newly constructed precast deck slab, (B) is a cross-sectional view taken along line ι of (A), (C) is a cross-sectional view taken along line κ of (A), and (D) is a diagram showing the state in which temporary reinforcement materials have been installed before the protective fence section is fixed by fixing members as in (B). (A) is a plan view showing a protective fence of the fourth embodiment in which a protective fence section is fixed to a newly constructed precast deck, (B) is a cross-sectional view taken along line λ of (A), and (C) is a cross-sectional view taken along line μ of (A). (A) is a plan view showing a protective fence according to the fifth embodiment in which a first protective fence section and a second protective fence section are fixed to a newly constructed precast deck, (B) is a cross-sectional view taken along line ν of (A), and (C) is a cross-sectional view taken along line ξ of (A). (A) is a plan view showing details of the connection portion in the top beam of Figure 10 (A), (B) is a cross-sectional view taken along line O of details of the connection portion in the middle beam of Figure 10 (C), and (C) is a diagram showing the state in which the second protective fence portion is connected to the first protective fence portion in the second protective fence portion installation process of the protective fence in Figure 10 (C). (A) is a plan view showing a protective fence according to the sixth embodiment in which a first protective fence section and a second protective fence section are fixed to a newly constructed precast deck slab, and (B) is a cross-sectional view taken along the pi line of (A). (A) is a plan view showing details of the connection portion in the top beam of Figure 12 (A), (B) is a plan view showing details of the connection portion in the middle beam of Figure 12 (B), and (C) is a diagram showing the state in which the second protective fence section is connected to the first protective fence section in the second protective fence section installation process of the protective fence of Figure 11 (C).

The guard fence, guard fence installation method, and deck replacement method according to the embodiments of the present invention will be described in detail below with reference to the drawings. The deck replacement method according to the first embodiment of the present invention is applied to replace the deck 20 of a road 50 having multiple lanes 51, 52 as shown in FIG. 1(A). The guard fence and guard fence installation method according to this embodiment are applied, for example, in the deck replacement method according to this embodiment.

As shown in FIG. 1(A), the existing deck 20 that forms the road 50 is erected on bridge girders 41. A pavement 28 is formed on most of the upper surface of the deck 20, which corresponds to the road surface of the road 50, excluding both ends in the width direction of the road 50. A wall parapet 42 is installed on both ends of the deck 20, which correspond to both ends in the width direction of the road 50. In the example of FIG. 1(A), the existing deck 20 is used as a road 50 with two lanes 51, 52 on each side for the passage of vehicles V.

In the deck replacement method of this embodiment, even during the work of replacing the deck 20 in one of the two lanes 51, 52 of the road 50, the other lane 51, 52 continues to be used for the passage of vehicles V. Therefore, in order to separate one of the lanes 51, 52 where the work of replacing the deck 20 is being carried out from the other lane 51, 52 used for the passage of vehicles V, a protective fence 1A that separates the road formed by the deck 20 is installed on the road 50, as shown in Figures 2(A), 2(B), 2(C), 4(A), 4(B), and 4(C).

As shown in FIG. 1B, the existing deck 20 is divided into two existing decks 21 and 22 along the travel direction of the road 50 and the lanes 51 and 52. The deck 21 is replaced first, and the deck 22 is used for the passage of vehicles V during the replacement work of the deck 21. As shown in FIG. 1B, in the deck replacement method of this embodiment, an existing deck through hole forming process is performed to form an existing deck through hole 22h (decoration through hole 20h) that vertically penetrates the existing deck 22 in a part of the lanes 52 of the multiple lanes 51 and 52. The existing deck through hole forming process corresponds to the deck through hole forming process in the protective fence installation method of this embodiment. The existing deck through hole 22h also vertically penetrates the pavement 28 on the upper surface of the existing deck 22.

In the existing deck through hole forming process, the existing deck through hole 22h is formed by drilling a hole from the upper surface of the existing deck 22, but it can also be formed by drilling a hole from the underside of the existing deck 22 with a drill bit or the like. In this case, in the existing deck through hole forming process, work on the road surface of the road 50 is not required. Therefore, the lanes 51, 52 can be used for the passage of vehicles V during the existing deck through hole forming process and the deck through hole forming process for the existing deck 22.

When the existing deck through hole 22h is formed by drilling from the underside of the existing deck 22, the passage of vehicles V may be restricted, for example, by placing a road cone or the like on the upper surface of the pavement 28 at the location where the existing deck through hole 22h is to be formed. Also, when the existing deck through hole 22h is formed by drilling from the underside of the existing deck 22 with a drill bit, an iron plate or the like may be laid on the upper surface of the pavement 28 at the location where the existing deck through hole 22h is to be formed, as necessary, so that the tip of the drill bit does not protrude from the upper surface of the pavement 28.

As shown in FIG. 1(C), the wall balustrade 42 is removed from the existing deck 21 to be replaced first. As shown in FIG. 1(C), FIG. 1(D), FIG. 2(A), FIG. 2(B), and FIG. 2(C), in the deck replacement method of this embodiment, a guard fence section 10A that divides a part of the lane 52 is placed on the pavement 28 of the existing deck 22 in which the existing deck through hole section 22h is formed in the existing deck through hole section forming process, and an existing deck guard fence section fixing process is performed in which the guard fence section 10A is fixed on the pavement 28 of the existing deck 22 by the fixing member 30 inserted into the existing deck through hole section 22h. The existing deck guard fence section fixing process corresponds to the guard fence section fixing process in the guard fence installation method of this embodiment.

2(B) and 2(C), the fixing member 30 is composed of a rod 31 protruding below the guardrail section 10A and a fastening member 32 that fits into the rod 31. For example, the rod 31 is a bolt, that is, a rod with a male thread, and a member consisting of a rod with a male thread and a head, and the fastening member 32 is, for example, a nut. As shown in FIG. 1(C), in the existing deck guardrail section fixing process, the guardrail section 10A is lowered vertically using a lifting machine such as an erection machine, and the rod 31 is inserted into the existing deck through hole 22h formed in the deck through hole forming process, and the guardrail section 10A is placed on the pavement 28 of the deck 22. Also, as shown in Figures 1(D), 2(A), 2(B), and 2(C), in the existing deck protective fence section fixing process, after the protective fence section 10A is placed on the deck 22, the protective fence section 10A is fixed onto the pavement 28 of the deck 22 by fitting the fastening member 32 to the rod 31 inserted into the existing deck through hole section 22h by working from the underside of the deck 22.

In addition, in the existing deck protective fence section fixing process, in order to secure the bearing area, a lower plate having an abutment surface that abuts against the underside of the deck 22 and an insertion hole through which the rod 31 is inserted may be applied. In the existing deck protective fence section fixing process, the lower plate may be attached to the rod 31 so that the rod 31 inserted into the existing deck slab through hole 22h is further inserted into the insertion hole of the lower plate, and then the fastening member 32 may be fitted to the rod 31, and the protective fence section 10A may be fixed by the fastening member 32 via the lower plate. This can increase the bearing area.

The following describes the guard fence 1A in this embodiment, in which the guard fence section 10A is fixed to the existing deck 22. As shown in Figures 2(A), 2(B) and 2(C), the guard fence 1A in this embodiment defines the road 50 formed by the decks 21 and 22. The guard fence 1A includes the existing deck 22, the guard fence section 10A that defines the road 50, the existing deck through hole section 22h (deck through hole section 20h) that vertically penetrates the deck 22, and the fixing member 30 (bar material 31 and fastening member 32) that is inserted into the existing deck through hole section 22h and fixes the guard fence section 10A to the deck 22.

The protective fence section 10A is made of steel. The protective fence section 10A has a support 11A, a beam 12A, a support base plate 13A, a reinforcing rib 14A, and a protective plate 15. The support 11A extends from the pavement 28 on the upper surface of the deck 22 in a direction perpendicular to the upper surface of the deck 22. The support 11A supports the beam 12A, which extends along the traveling direction of the road 50, from below the beam 12A. The support base plate 13A is a steel plate that extends in a direction parallel to the upper surface of the deck 22. The support base plate 13A is integrated with the support 11A at the lower end of the support 11A, and fixes the support 11A to the deck 22.

The support base plate 13A includes a plate hole portion 13h that penetrates the support base plate 13A vertically. The plate hole portion 13h includes a thread groove on its inner surface that corresponds to the thread groove of the bolt, which is the rod material 31 of the fixing member 30. In the above-mentioned existing deck slab protective fence section fixing process, the bolt, which is the rod material 31, is screwed into the plate hole portion 13h in advance to be integrated with the protective fence section 10A, and is transported and placed by an erection machine or the like in a state where it protrudes below the support base plate 13A of the protective fence section 10A.

Therefore, even immediately after the rod 31 is inserted into the existing deck through-hole 22h and the guard fence section 10A is placed on the deck 22, and before the fastening member 32 is fitted to the rod 31, the guard fence section 10A is placed on the deck 22 so as not to shift laterally. In this state, the guard fence section 10A functions as, for example, a Class A guard fence in the guard fence installation standards of the Ministry of Land, Infrastructure, Transport and Tourism. Therefore, even immediately after the guard fence section 10A is placed on the deck 22 and before the fastening member 32 is fitted to the rod 31, the lane 52 formed by the deck 22 can be used for the passage of vehicles V.

The inner diameter of the existing deck through hole 22h is sufficiently larger than the diameter of the rod 31. When the fastening member 32 is fitted to the rod 31, it is preferable that the outer peripheral surface of the rod 31 inserted into the existing deck through hole 22h and the inner peripheral surface of the existing deck through hole 22h are not in contact with each other. By making them not in contact, when the fastening member 32 is fitted to the rod 31, the protective fence section 10A is fixed to the deck 22 by the frictional force between the support base plate 13A and the deck 22. When the fastening member 32 is fitted to the rod 31, the protective fence section 10A functions as, for example, a type SB protective fence in the Ministry of Land, Infrastructure, Transport and Tourism's protective fence installation standards.

A pair of reinforcing ribs 14A are provided between the lower part of the side of the support pillar 11A facing the lane 51 and the side of the support pillar 11A facing the lane 52 and the support pillar base plate 13A. A pair of protective plates 15 extending in a direction perpendicular to the upper surface of the deck 22 and along the traveling direction of the road 50 are attached to the side of the support pillar 11A facing the lane 51 and the side of the support pillar 11A facing the lane 52 below the beam 12A.

The lane 52 partitioned by the above-mentioned guard fence 1A is made available for the passage of vehicles V, and as shown in FIG. 1(E), in the deck replacement method of this embodiment, the first existing deck removal process is carried out and completed to remove the existing deck 21 in the other lanes 51, excluding the lane 52 of the existing deck 22 to which the guard fence section 10A was fixed in the existing deck guard fence section fixing process.

Next, as shown in Figures 1(F), 3(A), 4(A), 4(B), and 4(C), in the deck replacement method of this embodiment, a first deck new installation process is carried out in which multiple precast decks 25 are placed on the lane 51 from which the existing deck 21 was removed in the first existing deck removal process. The first deck new installation process corresponds to the deck new installation process in the protective fence installation method of this embodiment.

As shown in Figures 1(F), 4(A), 4(B) and 4(C), in the first new deck construction process of the deck replacement method of this embodiment, multiple precast decks 25 are arranged with spaces between them in the direction of travel of the lane 51. As shown in Figures 3(A), 4(A), 4(B) and 4(C), in the first new deck construction process, multiple precast decks 25 are arranged with spaces between them in the direction of travel of the other lane 51, and then filler concrete 27 is poured on-site between the multiple precast decks 25.

In the first new floor slab construction process, when the filler concrete 27 is poured on site, a filler concrete through hole 27h (floor slab through hole 20h) that penetrates the filler concrete 27 vertically is formed. Therefore, like the above-mentioned existing floor slab through hole formation process, the first new floor slab construction process corresponds to the floor slab through hole formation process in the protective fence installation method of this embodiment. The filler concrete through hole 27h is formed, for example, by placing a void pipe corresponding to the shape of the filler concrete through hole 27h as a formwork when the filler concrete 27 is poured on site. A wall balustrade 43 is installed on the precast floor slab 25 and the filler concrete 27, and a pavement 28 is formed, completing the first new floor slab construction process.

By the above-mentioned first new deck construction process, a deck 23 having multiple precast decks 25 arranged at intervals in the direction of travel of the road 50 and concrete filling 27 poured on site between the multiple precast decks 25 is newly constructed in the lane 51. Even during the first existing deck removal process, the lane 52 remains in use for the passage of vehicles V.

As shown in Figures 3(B), 3(C), 4(A), 4(B) and 4(C), in the deck replacement construction method of this embodiment, a new deck slab protective fence section fixing process is carried out to fix the protective fence section 10A to the deck slab 23 newly installed in the first deck slab new installation process. As with the existing deck slab protective fence section fixing process described above, the new deck slab protective fence section fixing process corresponds to the protective fence section fixing process in the protective fence installation method of this embodiment.

In the new deck protective fence section fixing process, the fixing of the protective fence section 10A, which was fixed to the existing deck 22 in the existing deck protective fence section fixing process, to the existing deck 22 by the fixing members 30 (the rods 31 and the fastening members 32) is released. Specifically, the nuts, which are the fastening members 32, are removed from the bolts, which are the rods 31.

In the new deck slab protective fence section fixing process, the protective fence section 10A is moved and placed on the filler concrete 27 in which the filler concrete through hole section 27h was formed in the new deck slab construction process and on the pavement 28 of the multiple precast deck slabs 25. As with the existing deck slab protective fence section fixing process described above, in the new deck slab protective fence section fixing process, the rod material 31, which is the bolt, is screwed into the plate hole section 13h and integrated with the protective fence section 10A, and is transported and placed by an erection machine or the like in a state where it protrudes below the support base plate 13A of the protective fence section 10A.

In the new deck slab protective fence section fixing process, the protective fence section 10A is fixed onto the concrete filling 27 and the pavement 28 of the multiple precast deck slabs 25 by the fixing member 30 (rod 31) inserted into the concrete filling through hole 27h formed in the first new deck slab construction process. As with the existing deck slab protective fence section fixing process described above, in the new deck slab protective fence section fixing process, after the protective fence section 10A is placed on the deck slab 23, the protective fence section 10A is fixed to the deck slab 23 by fitting the fastening member 32 to the rod 31 inserted into the concrete filling through hole 27h by working from the underside of the deck slab 23.

As in the existing deck guard fence section fixing process, in the new deck guard fence section fixing process, a lower plate having a contact surface that contacts the underside of the precast deck 25 and an insertion hole through which the rod 31 is inserted may be applied in order to ensure a bearing area. In the new deck guard fence section fixing process, the lower plate may be attached to the rod 31 so that the rod 31 inserted into the fill concrete through hole 27h is further inserted into the insertion hole of the lower plate, and then the fastening member 32 may be fitted to the rod 31, and the guard fence section 10A may be fixed by the fastening member 32 via the lower plate.

As with the above-mentioned existing deck guard fence section fixing process, the bar 31 is inserted into the fill concrete through hole 27h, and the guard fence section 10A is placed on the deck 23 so as not to shift laterally, even before the fastening member 32 is fitted to the bar 31. In this state, the guard fence section 10A functions as a Class A guard fence in the guard fence installation standards of the Ministry of Land, Infrastructure, Transport and Tourism. Therefore, the lane 51 formed by the deck 23 can be used for the passage of vehicles V, even before the fastening member 32 is fitted to the bar 31, immediately after the guard fence section 10A is placed on the deck 23.

As with the above-mentioned existing deck protective fence fixing process, the inner diameter of the concrete through hole 27h is sufficiently larger than the diameter of the rod 31. When the fastening member 32 is fitted to the rod 31, it is preferable that the outer peripheral surface of the rod 31 inserted into the concrete through hole 27h and the inner peripheral surface of the concrete through hole 27h are not in contact with each other. By making them not in contact, when the fastening member 32 is fitted to the rod 31, the protective fence 10A is fixed to the deck 23 by the frictional force between the support base plate 13A and the deck 23 (filled concrete 27).

This ensures the quality of the fill concrete 27 against traffic vibrations of the lane 51 used for the passage of vehicles V and against loads when vehicles V come into contact with the guard fence section 10A. When the fastening members 32 are fitted into the bars 31, the guard fence section 10A functions as an SB type guard fence, for example, in the guard fence installation standards of the Ministry of Land, Infrastructure, Transport and Tourism. After the new deck guard fence section fixing process, the deck 22 is replaced after the deck 21, and the newly installed deck 23 is used for the passage of vehicles V during the work of replacing the deck 22.

As shown in Figures 4(A), 4(B) and 4(C), the guard fence 1A in which the guard fence section 10A is fixed to the newly installed deck 23 of this embodiment includes the deck 23, the guard fence section 10A that divides the road 50, the fill concrete through hole section 27h (deck through hole section 20h) that penetrates the deck 23 from top to bottom, and the fixing member 30 (bar material 31 and fastening member 32) that is inserted into the fill concrete through hole section 27h and fixes the guard fence section 10A to the deck. The deck 23 has a plurality of precast decks 25 arranged at intervals in the traveling direction of the road 50, and fill concrete 27 poured on site between the plurality of precast decks 25, and the fill concrete through hole section 27h is formed in the fill concrete 27.

The lane 51 defined by the above-mentioned guard fence 1A is used for the passage of vehicles V, and as shown in FIG. 3(D), in the deck replacement method of this embodiment, after the new deck guard fence part fixing process, a second existing deck removal process is performed to remove the existing deck 22 in the lane 52. Next, as shown in FIG. 3(E), the lane 51 defined by the guard fence 1A is used for the passage of vehicles V, and in the deck replacement method of this embodiment, a second new deck installation process is performed to place multiple precast decks 26 in the lane 52 from which the existing deck 22 was removed in the second existing deck removal process.

In the second floor slab construction process, as shown in FIG. 3(F), a tensioning process is performed in which a tensioning material 44 is inserted into the hole portion communicating with the precast floor slab 25 arranged in the first floor slab construction process and the precast floor slab 26 arranged in the second floor slab construction process, and tensioning force is applied to the precast floor slab 25 and the precast floor slab 26 by the tensioning material 44. In the second floor slab construction process, as shown in FIG. 3(G), filler concrete 27 is poured on site between the multiple precast floor slabs 26. By the above-mentioned second floor slab construction process, a floor slab 24 having multiple precast floor slabs 26 arranged at intervals in the traveling direction of the road 50 and filler concrete 27 poured on site between the multiple precast floor slabs 26 is newly constructed on the lane 52. A wall parapet 43 is installed on the floor slab 24, and a pavement 28 is formed on the floor slab 24.

5(A) and 5(B), in the second floor slab new installation process, the precast floor slab 25 arranged in the first floor slab new installation process and the precast floor slab 26 arranged in the second floor slab new installation process may be connected by the installation jig 70 between the placement of the precast floor slab 26 on the lane 52 and the end of the tensioning process. The installation jig 70 includes an upper abutment member 71 that abuts across the upper surface of the precast floor slab 25 and the upper surface of the precast floor slab 26, a lower abutment member 72 that abuts across the lower surface of the precast floor slab 25 and the lower surface of the precast floor slab 26, and a pair of fastening members (clamps) 73 that fasten the upper abutment member 71 and the lower abutment member 72. The installation jig 70 connects the precast deck 26 placed on the lane 52 to the precast deck 25 of the lane 51, which is used for the passage of the vehicle V and vibrates, until the tensioning process is completed. This suppresses the displacement of the precast decks 25, 26, improving the accuracy of construction.

When the precast decks 25, 26 are connected by the installation jig 70, for example, in the first deck new construction process, in order to secure space for the installation jig 70, the filler concrete 27 is not poured and the pavement 28 is not required to be formed in the area 100 to 200 mm inside the boundary between the precast deck 25 and the lane 52. In the new deck protective fence section fixing process, the protective fence section 10A may be fixed onto the filler concrete 27 and the pavement 28 of the multiple precast decks 25, as in Figures 4(A), 4(B), and 4(C).

In addition, as shown in Fig. 5(A) and Fig. 5(B), when the precast deck 25, 26 are connected by the installation jig 70, for example, in the first deck new construction process, in order to secure the space for the installation jig 70, the filler concrete 27 is not poured in the area 100 to 200 mm inside the boundary between the precast deck 25 and the lane 52, and in order to secure the space for the guard fence section 10A, the pavement 28 does not have to be formed in the area 200 to 400 mm inside the boundary between the precast deck 25 and the lane 52. In the new deck guard fence section fixing process, the guard fence section 10A is fixed via the height adjustment material 60 to the area of the precast deck 25 where the pavement 28 is not formed so that the guard fence section 10A is at an appropriate height relative to the top surface of the pavement 28.

Also, as shown in Figures 6(A) and 6(B), the precast decks 25, 26 are connected by the installation jig 70, and in the first deck new construction process, the filler concrete 27 is not poured in the area 100 to 200 mm inside from the boundary between the precast deck 25 and the lane 52, and the pavement 28 is not formed in the area 200 to 400 mm inside from the boundary between the precast deck 25 and the lane 52. In this case, for example, in the new deck protective fence section fixing process, the protective fence section 10A may be fixed directly to the area of the precast deck 25 where the pavement 28 is not formed. When the protective fence section 10A is fixed directly to the area of the precast deck 25 where the pavement 28 is not formed, the height of the protective fence section 10A may be increased in accordance with the thickness of the pavement 28.

In addition, in the areas of the precast deck 25 where the filler concrete 27 was not poured and the pavement 28 was not formed in the first deck construction process, the filler concrete 27 will be poured in a later process and the pavement 28 will be formed.

As shown in FIG. 3(G), a guard fence removal process is performed to remove the guard fence section 10A from the deck 23. In the guard fence removal process, the guard fence section 10A fixed to the deck 23 is released from the fixing members 30 (the rods 31 and the fastening members 32). Specifically, the nuts, which are the fastening members 32, are removed from the bolts, which are the rods 31. After the guard fence section 10A is removed by an erection machine or the like, the concrete through holes 27h are filled with a filler such as mortar. The lanes 51 and 52 on which the decks 23 and 24 are newly installed are again used for the passage of vehicles V. In this manner, the deck replacement method of this embodiment is completed.

In another technique for installing temporary guardrails on roads, a temporary guardrail made of reinforced concrete or steel is fixed to the deck by anchors driven into the top surface of the deck. However, in this method, the anchors must be driven into the side of the lane used for vehicle traffic to prevent the guardrail from collapsing due to contact with a vehicle. Therefore, in conventional techniques, a first temporary guardrail is first placed on the existing deck between the lane used for vehicle traffic and the lane where traffic is restricted. Next, a second temporary guardrail, fixed by anchors, is placed on the side of the lane where traffic is restricted of the first temporary guardrail.

At this point, traffic restrictions are imposed on the lane that was in use for vehicle traffic, and the lane that was subject to traffic restrictions is reopened to vehicle traffic. In this state, anchors are driven into the top surface of the deck on the side of the second temporary guardrail that is subject to traffic restrictions, and the temporary guardrail is fixed to the deck. The first temporary guardrail is removed. Traffic restrictions are again imposed on the lane that was in use for vehicle traffic on the side opposite to the side where the anchors of the second temporary guardrail were driven, and the lane that was subject to traffic restrictions on the side where the anchors of the second temporary guardrail were driven is reopened to vehicle traffic. In this state, the deck of the lane that was subject to traffic restrictions is replaced for the first time.

In other words, the anchors must be driven into the lane that is used for vehicle traffic, but traffic restrictions must be imposed on that lane in order to carry out this work. Therefore, with the conventional technology, it is necessary to switch twice between the lane that is used for vehicle traffic and the lane that is subject to traffic restrictions in order to install a temporary protective fence. In addition, traffic restrictions must also be imposed on that lane in order to remove an anchor that has been driven into the lane that is used for vehicle traffic. Therefore, with the conventional technology, it is necessary to switch twice between the lane that is used for vehicle traffic and the lane that is subject to traffic restrictions in order to remove a temporary protective fence. For this reason, with the conventional technology, the period of traffic restrictions related to the installation and removal of a temporary protective fence is long.

In addition, as described above, this method requires the installation of two temporary guardrails. In addition, the width of each individual temporary guardrail in the road width direction must be increased because the guardrail is fixed to the deck by anchors driven into the top surface of the deck. For this reason, this method imposes a large traffic restriction on the installation and removal of the temporary guardrail. Furthermore, this method requires that anchor holes be drilled into the newly installed precast deck, reducing the durability of the newly installed precast deck. In addition, in this method, the temporary guardrail is fixed to the deck by anchors, so the quality of the fixed part of the guardrail against traffic vibrations of the lane used for vehicle traffic and loads when a vehicle comes into contact with the guardrail is low.

On the other hand, preferably according to this embodiment, the protective fence 1A that divides the road 50 formed by the deck slabs 21, 22, 23, 24 comprises the deck slabs 22, 23, a protective fence section 10A that divides the road 50, a deck slab through-hole section 20h that penetrates the deck slabs 22, 23 vertically, and a fixing member 30 that is inserted into the deck slab through-hole section 20h and fixes the protective fence section 10 to the deck slabs 22, 23. The guardrail section 10A is fixed to the deck slabs 22, 23 by the fixing member 30 that is inserted into the deck through hole 20h that penetrates the deck slabs 22, 23 vertically and fixes the guardrail section 10A to the deck slabs 22, 23. Compared to the conventional technology in which a temporary guardrail is fixed to the deck slab by an anchor driven from above, more of the work required to fix the guardrail section 10A to the deck slabs 22, 23 can be done from the underside of the deck slabs 22, 23. Therefore, the traffic restriction period required to install the guardrail can be shortened.

In addition, according to this embodiment, in the deck replacement method, after the existing deck penetration hole forming process and the existing deck protective fence fixing process, in which the traffic restriction period is shortened, a first existing deck removal process is carried out in which the existing deck 22 in the other lanes 51 is removed while some of the lanes 52 divided by the protective fence section 10A are made available for the passage of vehicles V, and a first new deck construction process is carried out in which precast deck 25 is placed in the other lanes 51, thereby lengthening the period during which the road 50 can be used for the passage of vehicles V.

In addition, according to this embodiment, in the deck replacement construction method, in the new deck guard fence section fixing process, the guard fence section 10A fixed to the existing deck 22 in the existing deck guard fence section fixing process is released from the fixing member 30 between the existing deck 22 and the guard fence section 10A, and the guard fence section 10A is moved and positioned to the fill concrete 27 and the multiple precast deck slabs 25 in which the fill concrete through hole 27h has been formed in the new deck construction process, and the guard fence section 10A is fixed to the fill concrete 27 and the multiple precast deck slabs 25 by the fixing member 30 inserted into the fill concrete through hole 27h formed in the new deck construction process. Therefore, the traffic control period required to move the guard fence section 10A from the existing deck slab 22 and then install it on the precast deck slab 25 can be shortened.

In addition, after the process of fixing the new deck protective fence section, in which the traffic restriction period is shortened, a second existing deck removal process is carried out to remove the existing deck 22 in the lane 52 while keeping the lane 51 divided by the protective fence section 10A in service for vehicle passage, and a second new deck construction process is carried out to place a precast deck 26 in the lane 52, thereby lengthening the period during which the road 50 can be used for the passage of vehicles V.

In addition, according to this embodiment, there is no need to switch between lanes available for vehicle traffic and lanes subject to traffic restrictions in order to install and remove temporary protective fences. Therefore, according to this embodiment, the period of traffic restrictions related to the installation and removal of temporary protective fences can also be shortened during the lane switching period.

Furthermore, according to this embodiment, there is no need to install two temporary guardrails. Furthermore, the width of the guardrail section 10A in this embodiment in the width direction of the road can be made narrower than that of conventional temporary guardrails, because the guardrail section 10A is fixed to the deck slabs 22, 23 by the fixing member 30 inserted into the deck through-hole 20h. Therefore, according to this embodiment, the range of traffic restrictions related to the installation and removal of the temporary guardrail can be reduced.

In addition, according to the protective fence 1A of this embodiment, in the deck 23 having a plurality of precast decks 25 spaced apart in the direction of travel of the road 50 and interfacial concrete 27 poured on-site between the plurality of precast decks 25, the interfacial concrete through-holes 27h are formed in the interfacial concrete 27, and no holes are provided in the precast decks 25 that mainly constitute the deck 23, improving the durability of the deck 23.

In other words, in this embodiment, anchor holes are not drilled into the newly installed precast deck 25, and high durability of the newly installed precast deck 25 can be ensured. Also, in this embodiment, the guard fence section 10A is fixed to the deck 23 by the frictional force between the support base plate 13A and the deck 23. This ensures the quality of the fixed part of the guard fence section 10A against traffic vibrations of the lane 51 used for the passage of the vehicle V and loads when the vehicle V comes into contact with the guard fence section 10A.

In addition, in this embodiment, there is no need to fix anchors on the upper surfaces of the decks 22 and 23. Therefore, the safety of the work when installing and removing the guard fence section 10A is ensured. In addition, in this embodiment, the guard fence section 10A is made of steel, so the guard fence section 10A is lighter than a conventional guard fence made of reinforced concrete. Therefore, even when the guard fence section 10A is installed on the existing deck 22 that is divided into two and cantilevered into the existing deck 21 and deck 22, reinforcement of the existing deck 22 is not required, and the impact on the existing deck 22 can be reduced. In addition, the guard fence section 10A of this embodiment has a simple structure in which the guard fence section 10A is fixed to the deck 22 and 23 by the fixing member 30 inserted into the deck through hole 20h, so that it can be made less expensive than a conventional temporary guard fence.

In addition, according to the method for installing a protective fence of this embodiment, a plurality of precast slabs 25 are arranged in a line with spaces between them in the direction of travel of the road 50 in the new slab construction process to replace the existing ones, and then filler concrete 27 is poured on-site between the plurality of precast slabs 25. In the slab through-hole formation process, when the filler concrete 27 is poured on-site in the new slab construction process, a filler concrete through-hole 27h is formed in the filler concrete 27. Therefore, the pouring of the filler concrete 27 on-site and the formation of the filler concrete through-hole 27h can be performed simultaneously, making it easier to form the filler concrete through-hole 27h.

According to the method for installing the protective fence of this embodiment, the fixing member 30 is composed of a rod 31 protruding below the protective fence section 10A and a fastening member 32 that fits into the rod 31. In the protective fence section fixing process, the rod is inserted into the deck slab through hole 20h formed in the deck slab through hole forming process, and the protective fence section 10A is placed on the deck slabs 22, 23. Therefore, immediately after the protective fence section 10A is placed on the deck slabs 22, 23, the protective fence section 10A is placed on the deck slabs 22, 23 so as not to shift laterally. In the protective fence section fixing process, the fastening member 32 is fitted into the rod 31 inserted into the deck slab through hole 20h, thereby fixing the protective fence section 10A to the deck slabs 22, 23. Therefore, in the protective fence section fixing process, much of the work required to fix the protective fence section 10A to the deck slabs 22, 23 can be done from the underside of the deck slabs 22, 23. This shortens the traffic control period required to install the protective fence section 10A.

The following describes a guardrail according to the second embodiment of the present invention. As shown in Figures 7(A), 7(B), and 7(C), the guardrail 1B of this embodiment has a guardrail section 10B instead of the guardrail section 10A of the first embodiment. The guardrail section 10B has a beam 12B that is supported from below by the upper end of the support 11A and extends along the traveling direction of the road 50. The guardrail section 10B also has beams 12C that extend along the traveling direction of the road 50 on the side of the support 11A facing the lane 51 and the side of the support 11A facing the lane 52, at two positions midway along the height of the support 11A.

The protective fence section 10B is provided with a net 18 instead of the protective plate 15 of the protective fence section 10A of the first embodiment. The net 18 is supported by the center of the side of the support pillar 11A facing the traveling direction of the road 50 and the side opposite the traveling direction of the road 50, the center of the lower surface of the beam 12B, and the center of the upper surface of the support pillar base plate 13A. The net 18 extends in a direction perpendicular to the upper surface of the deck 23 and along the traveling direction of the road 50. The net 18 is made of metal or synthetic resin.

In this embodiment, the protective fence section 10B is equipped with a net 18 instead of a protective plate 15, which improves durability against wind loads on the road 50.

The following describes a guardrail according to the third embodiment of the present invention. As shown in Figures 8(A), 8(B) and 8(C), the guardrail 1C of this embodiment has a guardrail section 10C instead of the guardrail section 10A of the first embodiment. The guardrail section 10C includes openings 16A that open near the support base plate 13A in the guardrail plates 15 on both the lane 51 side used for the passage of vehicles V and the lane 52 side where the work of replacing the deck 22 is carried out.

In this embodiment, for example, in the process of fixing the new deck guard fence section, even if the bolt, which is the rod material 31, is not screwed into the plate hole portion 13h in advance, after the guard fence section 10B is placed on the deck 23, a worker can insert his or her hand into the opening 16A from the lane 52 side where the work of replacing the deck 22 is being carried out, and insert the rod material 31 into the plate hole portion 13h and the infill concrete through hole portion 27h while keeping the lane 51 open for the passage of vehicles V.

As shown in FIG. 8(D), after the guard fence portion 10C is placed on the deck 23, until the rod 31 is inserted through the plate hole portion 13h and the infill concrete through hole portion 27h, the guard fence portion 10C may be prevented from shifting toward the deck 22 due to contact with the vehicle V, etc., by a temporary reinforcement material 17 that can be moved on the deck 22 by casters, etc. If necessary from the viewpoint of the guidance of the vehicle V that comes into contact with the guard fence portion 10C, the opening 16A of the guard plate 15 on the side of the lane 51 used for the passage of the vehicle V may be blocked with a removable steel plate.

The protective fence section 10C of this embodiment can also be applied to the existing deck protective fence section fixing process. In this case, in the existing deck through hole forming process, the protective fence section 10C may be shifted from its original position on the existing deck 22 to the existing deck 21 side as a Class A protective fence in the Ministry of Land, Infrastructure, Transport and Tourism's protective fence installation standards, and then the existing deck through hole section 22h may be formed on the deck 22 side of the protective fence section 10C.

The following describes a guard fence according to the fourth embodiment of the present invention. As shown in Figures 9(A), 9(B) and 9(C), the guard fence 1D of this embodiment has a guard fence section 10D instead of the guard fence section 10A of the first embodiment. The guard fence section 10D is made of reinforced concrete and does not have a beam 12A or a guard plate 15. The guard fence section 10D has a support 11B, a support base plate 13B, a reinforcing rib 14B and an opening 16B. The support 11B is a steel pipe whose tip is embedded in the reinforced concrete of the guard fence section 10D. The support base plate 13B is a steel plate similar to the support base plate 13A of the first embodiment and includes a plate hole section 13h. The reinforcing rib 14B is similar to the reinforcing rib 14A of the first embodiment.

The opening 16B is a through hole portion that penetrates between the lane 51 side used for the passage of vehicles V and the lane 52 side where the work of replacing the deck 22 is performed, near the support base plate 13B. The opening 16B performs the same function as the opening 16A in the third embodiment. As in the third embodiment, if necessary from the viewpoint of the guidance of vehicles V that come into contact with the protective fence portion 10C, the lane 51 side of the opening 16B used for the passage of vehicles V may be closed with a removable steel plate.

The guard fence section 10D of this embodiment is made of reinforced concrete and is heavier than the steel guard fence section 10A of the first embodiment. Therefore, the rods 31, which are bolts, are not pre-threaded into the plate holes 13h. Even during the period from when the guard fence section 10D is placed on the deck 23 until the rods 31 are inserted into the plate holes 13h and the concrete through holes 27h, the guard fence section 10B can be prevented from shifting toward the deck 22 due to contact with the vehicle V, etc., without the need for temporary reinforcement 17 as in the second embodiment.

The following describes a guard fence and a guard fence installation method according to the fifth embodiment of the present invention. As shown in Figures 10(A), 10(B) and 10(C), the guard fence 1E of this embodiment includes, instead of the guard fence section 10A of the first embodiment, a first guard fence section 10e extending along the lanes 51, 52 of the road 50 divided by the guard fence 1E, and a second guard fence section 10E extending along the lanes 51, 52, continuous with the first guard fence section 10e. In this embodiment, the first guard fence section 10e and the second guard fence section 10E have the same configuration.

As shown in Figures 10(A), 10(B), 10(C), 11(A), 11(B) and 11(C), the connection portion 19A connecting the first protective fence portion 10e and the second protective fence portion 10E has a convex portion 19a on one side and a concave portion 19b on the other side when viewed vertically, and the convex portion 19a and the concave portion 19b can fit together. In addition, the convex portion 19a and the concave portion 19b have locking portions 19x and 19y that limit movement in the direction along the lanes 51 and 52.

In this embodiment, the first protective fence section 10e and the second protective fence section 10E have the same configuration, so the first protective fence section 10e and the second protective fence section 10E have a convex section 19a at one connection section 19A and a concave section 19b at the other connection section 19A. Note that, for example, the first protective fence section 10e may have either the convex section 19a or the concave section 19b at both connection sections 19A, and the second protective fence section 10E may have the other of the convex section 19a or the concave section 19b at both connection sections 19A.

The first and second protective fence sections 10e and 10E have a support 11C, a beam 12D, a beam 12E, and a support base plate 13C. The beam 12D is supported from below by the upper ends of the two supports 11C and extends along the traveling direction of the road 50. The beam 12E extends along the traveling direction of the road 50 at two positions midway between the height of the two supports 11C, on the side of the support 11C facing the lane 51 and the side of the support 11C facing the lane 52. Both ends of the beams 12D and 12E are located at the same position, separated from the support 11C, when viewed vertically. The support base plate 13C is a steel plate similar to the support base plate 13A of the first embodiment, and includes a plate hole portion 13h.

The first and second protective fence sections 10e and 10E have a fitting vertical member 19v at one of the connection sections 19A. The fitting vertical member 19v extends vertically from the upper end of the beam 12, passing between the two upper beams 12E and between the two lower beams 12E, to the lower end of the lower beam 12E. When viewed vertically, a part of the fitting vertical member 19v protrudes from the ends of the beams 12D and 12E. The part of the fitting vertical member 19v protruding from the ends of the beams 12D and 12E forms the convex portion 19a. When viewed vertically, a protrusion protrudes from the side of the tip of the convex portion 19a facing the lane 51 and the side of the tip of the convex portion 19a facing the lane 52. The protrusion protrudes over the entire vertical range of the fitting vertical member 19v that forms the convex portion 19a. The protrusion forms the locking portion 19x.

The first and second protective fence sections 10e and 10E have cutouts in the beams 12D and 12E of the other connection section 19A that correspond to the shape of the protrusion 19a when viewed vertically. The cutouts form the recesses 19b. When viewed vertically, the cutouts include a portion that is further recessed in the lateral direction intersecting with the lanes 51 and 52 and can accommodate the protrusion of the locking portion 19x. The portion of the cutout that is recessed in the lateral direction intersecting with the lanes 51 and 52 forms the locking portion 19y. The protrusions 19a and the recesses 19b are composed of surfaces that extend in the vertical direction. The protrusions 19a and the recesses 19b face each other so that the surfaces extending in the vertical direction are in contact with each other and engage with each other. The engaged protrusions 19a and the recesses 19b can slide against each other in the vertical direction and mutually restrict movement in the lateral direction intersecting with the lanes 51 and 52.

The locking portion 19x protrudes in a lateral direction intersecting the lanes 51 and 52. The locking portion 19y is recessed in a lateral direction intersecting the lanes 51 and 52. The locking portion 19x and the locking portion 19y engage with each other, so that the mated protrusion 19a and recess 19b restrict each other from moving away from each other. Therefore, the first protective fence portion 10e and the second protective fence portion 10E are mated with each other at the connection portion 19A.

Furthermore, the guard fence 1E of this embodiment, like the first embodiment, includes a deck through hole 20h that penetrates the deck 23 from top to bottom, and a fixing member 30 consisting of a rod 31 that protrudes downward from the first guard fence section 10e and the second guard fence section 10E, which is inserted into the deck through hole 20h and fixes the first guard fence section 10e and the second guard fence section 10E to the deck 23. The deck through hole 20h is a fill concrete through hole 27h, like the guard fence 1A of the first embodiment. The guard fence 1E of this embodiment can be applied to both the deck 22 and the deck 23, like the guard fence 1A of the first embodiment.

In the method for installing the guardrail of this embodiment, as shown in FIG. 11(C), in the existing deck guardrail section fixing process and the new deck guardrail section fixing process in the deck replacement construction method of the first embodiment, a first guardrail section installation process is performed in which a first guardrail section 10e is installed so as to extend along the lanes 51, 52 of the road 50 partitioned by the guardrail section 1E. In addition, a second guardrail section installation process is performed in which a second guardrail section 10E is installed so as to extend along the lanes 51, 52, continuous with the first guardrail section 10e installed in the first guardrail section installation process.

In the first and second protective fence section installation steps, the connection section 19A connecting the first and second protective fence sections 10e and 10E has a convex section 19a on one side and a concave section 19b on the other side when viewed vertically, and the first and second protective fence sections 10e and 10E are installed such that the convex section 19a and the concave section 19b can fit together. As shown in FIG. 11(C), in the second protective fence section installation step, the convex section 19a and the concave section 19b are fitted together, and a lifting machine such as an erection machine is used to vertically lower the second protective fence section 10E installed in the first protective fence section installation step and slide it downward to install the second protective fence section 10E.

In the first and second protective fence section installation processes, the first and second protective fence sections 10e and 10E are installed on the convex section 19a and the concave section 19b, which have locking sections 19x and 19y that limit movement in the direction along the lanes 51 and 52. In the second protective fence section installation process, the locking sections 19x and 19y are engaged with each other while the convex section 19a and the concave section 19b are fitted together, and while restricting the movement of the fitted convex section 19a and the concave section 19b in the direction away from each other, the second protective fence section 10E is slid downward relative to the first protective fence section 10e installed in the first protective fence section installation process, thereby installing the second protective fence section 10E.

In the first protective fence section installation process, the first protective fence section 10e, which is made of a rod 31 protruding below the first protective fence section 10e and has a fixing member 30 that fixes the first protective fence section 10e to the deck 22, 23, is installed on the deck 22, 23 having a deck through hole 20h that penetrates the deck 22, 23 vertically, while the rod 31 is inserted through the deck through hole 20h. In the second protective fence section installation process, the second protective fence section 20E, which is made of a rod 31 protruding below the second protective fence section 10E and has a fixing member 30 that fixes the second protective fence section 20E to the deck 22, 23, is installed on the deck 22, 23 having a deck through hole 20h, while the rod 31 is inserted through the deck through hole 20h.

When the first protective fence section 10e and the second protective fence section 10E are installed on the deck 23 newly constructed in the first protective fence section installation process and the second protective fence section installation process, in the first protective fence section installation process and the second protective fence section installation process, the first protective fence section 10e and the second protective fence section 10E are installed while inserting the rod 31 through the filling concrete through hole section 27h.

In FIG. 11(C), the second protective fence section 10E can be installed by repeating the installation of the second protective fence section 10E by the second protective fence section installation process similar to that described above so that it extends along the lanes 51, 52 of the road 50 in a continuous manner from the second protective fence section 10E installed in the second protective fence section installation process. In addition, depending on the situation, for example, the second protective fence section 10E may be installed by the second protective fence section installation process similar to that described above between two first protective fence sections 10e installed at a distance corresponding to the second protective fence section 10E along the lanes 51, 52 of the road 50 in the first protective fence section installation process so that it extends along the lanes 51, 52 of the road 50 in a continuous manner from each of the first protective fence sections 10e.

According to this embodiment, in the protective fence 1E that divides the road 50 formed by the deck 22, 23, the protective fence 1E includes a first protective fence section 10e that extends along the lanes 51, 52 of the road 50 divided by the protective fence 1E, and a second protective fence section 10E that extends along the lanes 51, 52, continuing from the first protective fence section 10e. The connection section 19A that connects the first protective fence section 10e and the second protective fence section 10E has a convex section 19a on one side and a concave section 19b on the other side when viewed vertically, and the convex section 19a and the concave section 19b can be fitted together, so that it is easy to connect the first protective fence section 10e and the second protective fence section 10E, and the traffic restriction period required to install the protective fence 1E can be shortened.

In addition, according to this embodiment, the convex portion 19a and the concave portion 19b have locking portions 19x, 19y that limit movement in the direction along the lanes 51, 52, making it easy to connect the first protective fence portion 10e and the second protective fence portion 10E, and shortening the traffic restriction period required to install the protective fence 1E.

In addition, according to this embodiment, the first and second protective fence sections 10e and 10E are fixed to the floor slabs 22 and 23 by the fixing members 30 that are inserted into the floor slab through-holes 20h that penetrate the floor slabs 22 and 23 vertically and fix the first and second protective fence sections 10e and 10E to the floor slabs 22 and 23. Compared to the conventional technology in which a temporary protective fence is fixed to the floor slab by anchors driven into the upper surface of the floor slab, more of the work required to fix the protective fence sections to the floor slab can be done from the underside of the floor slab. Therefore, the traffic restriction period required to install the protective fence can be shortened. In addition, the first and second protective fence sections 10e and 10E are connected by fitting with each other at the connection section 19A, so they have the strength to withstand the impact of a vehicle that deviates from the lane.

The following describes a guard fence and a guard fence installation method according to the sixth embodiment of the present invention. As shown in Fig. 12(A) and Fig. 12(B), the guard fence 1F of this embodiment has a first guard fence section 10f and a second guard fence section 10F instead of the first guard fence section 10e and the second guard fence section 10E of the fifth embodiment. In this embodiment, the first guard fence section 10f and the second guard fence section 10F have the same configuration. As shown in Fig. 12(A), Fig. 12(B), Fig. 13(A), Fig. 13(B), and Fig. 13(C), the connection section 19B connecting the first guard fence section 10f and the second guard fence section 10F has a convex section 19m on one side and a concave section 19n on the other side when viewed vertically, and the convex section 19m and the concave section 19n can be fitted together.

Beam 12D is supported from below by the upper ends of three pillars 11C and extends along the traveling direction of road 50. Beam 12E extends along the traveling direction of road 50 on the side of pillar 11C facing lane 51 and the side of pillar 11C facing lane 52 at two positions midway in the height direction of three pillars 11C.

In this embodiment, the first protective fence section 10f and the second protective fence section 10F have the same configuration, so the first protective fence section 10f and the second protective fence section 10F have a convex section 19m at one connection section 19B and a concave section 19n at the other connection section 19B. Note that, for example, the first protective fence section 10f may have either the convex section 19m or the concave section 19n at both connection sections 19B, and the second protective fence section 10F may have the other of the convex section 19m or the concave section 19n at both connection sections 19B.

The first and second protective fence sections 10f and 10F have protruding rectangular convex portions 19m when viewed vertically at the ends of the beams 12D of one of the connecting sections 19B. Bridging members 19p are bridged between the ends of the upper two beams 12E and the ends of the lower two beams 12E of one of the connecting sections 19B. The first and second protective fence sections 10f and 10F have protruding rectangular convex portions 19m when viewed vertically at the ends of the upper and lower bridging members 19p.

The first and second protective fence sections 10f and 10F also have rectangular recesses 19n in a vertical view at the ends of the beams 12D of the other connecting section 19B. Bridging members 19q are bridged between the ends of the upper two beams 12E and between the ends of the lower two beams 12E of the other connecting section 19B. The first and second protective fence sections 10f and 10F also have rectangular recesses 19n in a vertical view at the ends of the upper and lower bridging members 19q.

The convex portion 19m and the concave portion 19n are composed of surfaces extending in the vertical direction. The convex portion 19m and the concave portion 19n are opposed to each other so that the surfaces extending in the vertical direction are in contact with each other, and are fitted to each other. The fitted convex portion 19m and the concave portion 19n can slide against each other in the vertical direction, and mutually restrict movement in the lateral direction that intersects with the lanes 51, 52.

The protruding portion 19m may protrude into a shape other than a rectangle, such as a trapezoid when viewed vertically. The recessed portion 19n may be recessed into a shape other than a rectangle, such as a trapezoid when viewed vertically. The connection portion 19B formed by the protruding portion 19m and the recessed portion 19n in this embodiment may be formed by any of the following: a staggered joint, a dovetail joint, a sickle joint, a double staggered sickle joint, a tensioned staggered dovetail joint, a tensioned staggered sickle joint, a double staggered covered sickle joint, a hidden staggered joint, a dovetail joint, a sickle joint, a double staggered floor sickle joint, a box staggered joint, and a four-sided sickle joint.

In addition, the convex portion 19m and the concave portion 19n of this embodiment do not have the locking portions 19x, 19y like the convex portion 19a and the concave portion 19b of the fifth embodiment, but the convex portion 19m and the concave portion 19n that are fitted together may be restricted from moving apart from each other by any of the following: dovetail joint, sickle joint, double staggered sickle joint, tensioned staggered dovetail joint, tensioned staggered sickle joint, double staggered over sickle joint, dovetail joint, sickle joint, double staggered floor sickle joint, and four-sided sickle joint. According to this embodiment, the connection portion 19B can be formed with a simple structure.

13C, in the method of installing a protective fence of this embodiment, as in the fifth embodiment, a first protective fence section installation step of installing a first protective fence section 10f and a second protective fence section installation step of installing a second protective fence section 10F are performed. In FIG. 13C, by repeatedly installing the second protective fence section 10F so that it extends along the lanes 51, 52 of the road 50 in continuation from the second protective fence section 10F installed in the second protective fence section installation step, it is possible to install the first protective fence section 10f and the second protective fence section 10F that extend continuously along the lanes 51, 52 of the road 50. Depending on the situation, for example, the second protective fence section 10F may be installed between two first protective fence sections 10f that are installed along the lanes 51, 52 of the road 50 at a distance corresponding to the second protective fence section 10F in the first protective fence section installation process so as to extend along the lanes 51, 52 of the road 50, continuous with each of the first protective fence sections 10f.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment and may be implemented in various forms. For example, in the above embodiment, the configuration and quantity of the beams 12A, 12B, 12C, 12D, and 12E, the reinforcing ribs 14A and 14B, the protective plate 15, the net 18, and the fixing members 30 may be changed as appropriate.

1A, 1B, 1C, 1D, 1E, 1F...protective fence, 10A, 10B, 10C, 10D...protective fence section, 10e...first protective fence section, 10E...second protective fence section, 10f...first protective fence section, 10F...second protective fence section, 11A, 11B, 11C...support, 12A, 12B, 12C, 12D, 12E...beam, 13A, 13B, 13C...support base plate, 13h...plate hole section, 14A, 14B...reinforcement rib, 15...protective plate, 16A, 16B...opening, 17...temporary reinforcement material, 18...net, 19A, 19B...connection section, 19v...fitting vertical member, 19a...convex portion, 19b...concave portion, 1 9x, 19y... retaining portion, 19m... convex portion, 19n... concave portion, 19p, 19q... bridging member, 20, 21, 22, 23, 24... deck, 20h... deck through hole, 22h... existing deck through hole, 25, 26... precast deck, 27... concrete filling, 27h... concrete filling through hole, 28... pavement, 30... fixing member, 31... rod, 32... fastening member, 41... bridge girder, 42, 43... wall railing, 44... tension member, 50... road, 51, 52... lane, 60... height adjustment member, 70... erection jig, 71... upper contact member, 72... lower contact member, 73... fastening member (clamp), V... vehicle.

Claims (3)

A method for installing a guardrail for replacing a deck of a road having multiple lanes , comprising:
The project will include a new deck construction process in which multiple precast decks will be placed on lanes where existing decks have been removed.
In the new floor slab construction process, the plurality of precast floor slabs are arranged in a line with gaps in the travel direction of the lane , and then filler concrete is poured on-site between the plurality of precast floor slabs. When the filler concrete is poured on-site, a filler concrete through-hole portion is formed that penetrates the filler concrete vertically.
a newly constructed deck protective fence section fixing process in which a protective fence section is placed on the filler concrete and the multiple precast decks in which the filler concrete through hole section has been formed in the new deck construction process, and the protective fence section is fixed to the filler concrete and the multiple precast decks by a fixing member inserted into the filler concrete through hole section formed in the new deck construction process;
After the newly installed deck guardrail fixing process , an existing deck removal process is performed to remove the existing deck in some lanes ;
A new deck installation process of placing a plurality of precast decks on the part of the lanes from which the existing decks have been removed in the existing deck removal process;
Further equipped with
The deck,
The protective fence portion that divides the road;
A deck through hole portion that vertically penetrates the deck;
The fixing member is inserted into the deck through hole and fixes the protective fence to the deck;
Equipped with
How to install a protective fence . The floor slab and
A protective fence section that divides the road;
A deck through hole portion that vertically penetrates the deck;
A fixing member that is inserted through the deck through-hole and fixes the protective fence to the deck;
Equipped with
The deck includes a plurality of precast decks arranged at intervals in the traveling direction of the road, and filler concrete poured on site between the plurality of precast decks,
A protective fence installation method in which the deck through-hole portion is formed in the fill concrete,
When the filler concrete is poured on site, a filler concrete through hole portion is formed which penetrates the filler concrete vertically.
How to install a protective fence. A formwork corresponding to the shape of the filler concrete through hole is placed.
A method for installing a protective fence as claimed in claim 1 or claim 2.