Simple slab jointing method in bridge

Abstract

To improve on-site productivity and ensure quality using the so-called no-joint construction method, which simply connects slabs without using bridge expansion devices.SOLUTION: A bridge structure construction method by jointing slabs 20 in a bridge without using bridge expansion devices includes: step (S1) of fixing joint panels (PCa joint panels 10) to a road structure (slab 20) by penetrating the joint panels and inserting a reinforcement anchor 13; step (S2) of casting filler materials 14 in the gap of the joint panels; and step (S3) of constructing surface materials 40 (paving material made of asphalt, concrete, etc.) on the top of the joint panels. The joint panels can be configured from PCa panels. When repairing the bridge structure built by each step, only the surface materials 40 are repaired or replaced, with the joint panels remaining.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a simple connection method for a floor slab in a bridge, and more particularly to a so-called no-joint method for simply connecting floor slabs without using a bridge expansion device.

Background Art

[0002] Bridge expansion devices are subject to wear and damage caused by vehicle traffic and must be replaced and repaired in a timely manner. Conventionally, in the removal work of bridge expansion devices when replacing and repairing bridge expansion devices, chiseling work using a breaker or the like by manpower has been carried out. In this chiseling work, noise is generated by the breaker. In addition, the boundary between the part to be removed and the substructure is likely to become unclear, and the substructure may be unnecessarily damaged, which may affect the soundness of the bridge. Furthermore, in order to fix the bridge expansion device to the floor slab, substructure, etc., a large number of fixing anchors are provided on the floor slab and used for fixing to the bridge expansion device. When replacing and repairing, it is necessary to cut all the anchors, etc., which makes the work complicated.

[0003] In order to eliminate the above-mentioned disadvantages, a so-called no-joint method for connecting floor slabs by omitting the installation of bridge expansion devices as much as possible has been proposed. (See, for example, Patent Documents 1 to 3). The technique described in Patent Document 1 relates to a connection structure and a connection method in an existing steel truss bridge for connecting and integrating steel main trusses with different configurations in the upper structure of a steel truss bridge to make it jointless.

[0004] The technique described in this Patent Document 1 is a connection structure of a steel truss bridge in which a plurality of upper structures each having a steel main truss in the bridge axis direction L arranged at a predetermined interval in the direction W perpendicular to the bridge axis are arranged along the bridge axis direction L, and the steel main trusses are connected to a connecting cross girder arranged along the direction perpendicular to the bridge axis and arranged between adjacent upper structures along the bridge axis direction.

[0005] The technology described in Patent Document 2 relates to a connecting structure for making the superstructure of a steel girder bridge equipped with various main girder structures jointless, and to a connecting method for existing steel girder bridges.

[0006] The technology described in Patent Document 2 is a connecting structure for a steel girder bridge in which a plurality of superstructures are arranged in the direction L of the bridge axis, each superstructure comprising steel main girders in the direction perpendicular to the bridge axis and arranged at predetermined intervals in the direction W perpendicular to the bridge axis, and steel transverse girders in the direction perpendicular to the bridge axis and arranged near the ends of the steel main girders. In this structure, the connecting concrete is provided between the steel transverse girders at the opposing portions of adjacent superstructures in the direction of the bridge axis, and PC steel bars connect the steel transverse girders. Furthermore, the PC steel bars are positioned on the upper part of the steel main girders, and the connecting concrete is provided at a predetermined height higher than the lower flange of the steel main girders.

[0007] The technology described in Patent Document 3 aims to enable smooth passage of traffic loads by improving durability while avoiding premature deterioration of the surface asphalt pavement, and to enable construction in a short time, by partially suppressing the rotational displacement of the girder ends due to the loading of traffic loads and the expansion and contraction deformation due to temperature changes, etc., with a partial connection structure in a continuous bridge joint structure, and absorbing the remainder with the deformation performance of the joint member.

[0008] The technology described in Patent Document 3 involves forming a partial connection structure by pouring mortar into notches provided on the upper part of adjacent RC deck slabs of a bridge girder to partially integrate the ends of the deck slabs. A plate-shaped precast joint plate made of a high-toughness fiber-reinforced cement composite material, which has high pseudo-elongation performance due to crack dispersion, high tensile and bending deformation capacity, and vertical stiffness almost equivalent to that of an RC deck slab, is installed on the upper surface of this partial connection structure and on the upper surfaces of the deck slabs to its left and right. A waterproof sheet is then placed on top of this, and the top is covered with paving material. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Japanese Patent Publication No. 2017-133309 [Patent Document 2] Japanese Patent Publication No. 2018-31235 [Patent Document 3] Japanese Patent Publication No. 2008-190130 [Overview of the Initiative] [Problems that the invention aims to solve]

[0010] As mentioned above, in the conventional construction method that eliminates expansion joints, which are a heavy maintenance burden for road administrators, and instead connects the deck slabs simply on-site to create a jointless surface, the existing expansion joints are first removed, then reinforcing bars for connecting the deck slabs are placed, and anchoring devices such as reinforcing bars to secure the bars to the deck slabs are installed. Then, ultra-fast-setting concrete is poured using a mobile concrete plant, and after the concrete hardens, surface paving is applied and the road is opened to traffic. However, this construction procedure requires precise reinforcing bar placement, which tends to make the work complicated. In addition, mobile concrete plants for pouring ultra-fast-setting concrete are expensive and their number is limited, so it was sometimes impossible to arrange a mobile concrete plant, especially during peak seasons. A mobile concrete plant is a mobile concrete plant equipped with a mixer that can continuously mix special concrete and special mortar on-site.

[0011] The problems with conventional technology can be summarized as follows: Firstly, the work is complicated because precise reinforcement bar placement is required for connecting the deck slabs. Secondly, since construction is basically carried out under traffic restrictions that involve time constraints, it is necessary to shorten the working time. Thirdly, mobile construction vehicles are expensive and there is a risk that they cannot be arranged when needed, even during peak seasons. Fourthly, manual labor is predominant, and the quality and durability of the site depend on the quality of work during construction. Fifthly, as skilled workers are aging, it is becoming difficult to secure workers, including skilled workers.

[0012] This invention was proposed in view of the above circumstances, and aims to provide a simple method for connecting bridge decks in a so-called no-joint method that allows for easy connection of decks without using bridge expansion joints, thereby improving on-site productivity and ensuring quality. [Means for solving the problem]

[0013] The simplified bridge deck slab connection method according to the present invention has the following features in order to achieve the above-mentioned objectives.

[0014] The present invention relates to a simple bridge deck slab connection method, which is a method for constructing a bridge structure by connecting bridge deck slabs without using bridge expansion joints, and includes the following steps (a) to (c): (a) a step of fixing the connecting panel to the road structure by inserting reinforcing anchors through the connecting panel; (b) a step of casting infill material into the gaps of the connecting panel; (c) a step of installing a surface material (such as asphalt, concrete, or various precast members like precast concrete slabs) on top of the connecting panel.

[0015] In the simplified bridge deck slab connection method described above, the connecting panels can be constructed using precast concrete (PCa) panels.

[0016] Furthermore, when repairing bridge structures constructed through each process, it is possible to leave the connecting panels in place and replace only the surface material (asphalt, concrete, etc.).

[0017] Furthermore, if bridge expansion joints have already been installed, it is possible to construct the bridge structure by removing the bridge expansion joints and then carrying out the above-mentioned steps to simply connect the deck slabs. [Effects of the Invention]

[0018] The simple connection method for the floor slab in the bridge according to the present invention is a method for simply connecting the floor slab without using a bridge expansion device, so it is possible to improve productivity and ensure quality at the construction site. In addition, by using a PCa panel as the connection panel installed on the upper part of the floor slab, the bridge structure can be easily constructed, and it is possible to shorten the construction time, reduce the construction cost, and reduce the impact on the surrounding environment.

[0019] Therefore, according to the simple connection method for the floor slab in the bridge according to the present invention, in the so-called no-joint method, it is possible to improve productivity and ensure quality at the construction site. In addition, the simple connection method for the floor slab in the bridge according to the present invention is a technology applicable when making a bridge with an existing bridge expansion device jointless.

Brief Description of the Drawings

[0020] [Figure 1] A flowchart showing the procedure of the simple connection method for the floor slab in the bridge according to an embodiment of the present invention. [Figure 2] A schematic diagram of the PCa connection panel used in the simple connection method for the floor slab in the bridge according to an embodiment of the present invention. [Figure 3] A schematic diagram showing the procedure of the simple connection method for the floor slab in the bridge according to an embodiment of the present invention (when an existing bridge expansion device is installed). [Figure 4] A schematic diagram showing the procedure of the simple connection method for the floor slab in the bridge according to an embodiment of the present invention (the preparation state of installing the PCa connection panel). [Figure 5] A schematic diagram showing the procedure of the simple connection method for the floor slab in the bridge according to an embodiment of the present invention (the installation process of the PCa connection panel). [Figure 6] A schematic diagram showing the procedure of the simple connection method for the floor slab in the bridge according to an embodiment of the present invention (the filling process of the filler). [Figure 7] A schematic diagram showing the procedure of the simple connection method for the floor slab in the bridge according to an embodiment of the present invention (the construction process of the surface layer material).

Embodiments for Carrying Out the Invention

[0021] Referring to the drawings, a simplified bridge deck slab connection method (hereinafter sometimes referred to as the simplified bridge deck connection method) according to an embodiment of the present invention will be explained. Figures 1 to 7 illustrate the simplified bridge deck connection method according to an embodiment of the present invention. Figure 1 is a flowchart showing the procedure of the simplified bridge deck connection method (a: when there is no existing bridge expansion joint, b: when there is an existing bridge expansion joint), Figure 2 is a schematic diagram of the PCa connection panel used in the simplified bridge deck connection method (a: plan view, b: longitudinal section view, c: side view), and Figures 3 to 7 are schematic diagrams showing the procedure of the simplified bridge deck connection method. Note that in Figure 1(a), "when there is no existing bridge expansion joint" refers to cases where a new connection panel is installed, such as in the construction of a new bridge, replacement of a bridge, or replacement of a bridge deck.

[0022] <Overview of the simplified bridge slab connection method> The simplified bridge deck connection method according to the present invention is a technology relating to a so-called no-joint method that does not use bridge expansion joints. As shown in Figure 1(a), the main steps are: (S1) fixing the connection panel to the road structure (e.g., bridge deck) by inserting reinforcing anchors through the connection panel; (S2) casting infill material into the gaps of the connection panel; and (S3) applying surface material (asphalt, concrete, various precast members such as precast concrete slabs, etc.) to the top of the connection panel. Furthermore, if an existing bridge expansion joint is installed, as shown in Figure 1(b), the existing bridge expansion joint and surface material are removed (S11), and the above-mentioned connection panel fixing step (S1), infill material casting step (S2), and surface material application step (S3) are carried out.

[0023] This simplified bridge deck connection method is particularly suitable for bridges where the axial length of the bridge piers is short. Furthermore, as mentioned above, it can be applied not only to new constructions such as new bridges, bridge replacements, and bridge deck replacements, but also to bridge structures where bridge expansion joints have already been installed.

[0024] In the following description, the most preferred example of the connecting panel, i.e., the PCa-transformed connecting panel, will be described. However, as long as various conditions such as ease of construction, cost, durability, etc. can be satisfied, connecting panels made of steel, FRP, etc. can also be used.

[0025] <PCa connecting panel> The present invention is characterized by constructing a bridge structure by omitting the expansion device for bridges, and it is particularly preferable to use a PCa (Precast Concrete) connecting panel. The PCa connecting panel 10 of this embodiment is a member prefabricated in a factory in advance. As shown in FIG. 2, this PCa connecting panel 10 has a plurality of reinforcing bars 11 arranged inside, and concrete 12 is placed in a lattice (grid-like) pattern.

[0026] The PCa connecting panel 10 is fixed to the floor slab 20 using a plurality of shear bars 13 (see FIGS. 5 to 7). For example, after the PCa connecting panel 10 is installed on the floor slab 20, the shear bars 13 are welded to the reinforcing bars 11 of the PCa connecting panel 10. Then, by filling the gap of the PCa connecting panel 10 with a filler 14, the PCa connecting panel 10 is fixed to the floor slab 20. The filler 14 is appropriately selected and used from materials such as concrete and mortar according to the construction conditions.

[0027] Also, in this embodiment, the PCa connecting panel 10 having a structure fixed to the floor slab 20 is shown, but the PCa connecting panel 10 may be PCa-transformed integrally with the floor slab 20. That is, the PCa-transformed floor slab 20 and the PCa connecting panel 10 PCa-transformed integrally with the floor slab 20 can function as the PCa connecting panel 10 defined in the present invention.

[0028] <Expansion device body> The present invention is intended for use in bridge structures that omit bridge expansion joints. However, if bridge expansion joints are already installed, the simplified bridge deck connection method according to the present invention can be applied after removing the bridge expansion joints. As shown in Figure 3, a bridge expansion joint is configured to include an expansion joint body 30. This expansion joint body 30 is a device that allows the bridge girder to expand and contract without restricting thermal expansion and contraction or creep, and without impairing the driving performance of vehicles and other vehicles passing over the bridge.

[0029] The expansion joint body 30 in this embodiment is a conventionally used device with a general structure, and as shown in Figure 3, it has a main body 31 installed near the center in the direction of the extension of the road (direction of vehicle travel). The main body 31 is supported by a plurality of reinforcing bars 32 and is embedded inside the surface material 40. The expansion joint body 30 is fixed to the floor slab 20 by embedding the lower ends (anchor bars) of the reinforcing bars 32 into the floor slab 20. The expansion joint body 30 is also provided with a first waterproofing mechanism 33 located on the upper part of the main body 31 and a second waterproofing mechanism 34 that spans between the lower ends of adjacent surface material 40s.

[0030] <Construction procedure for the simplified floor slab connection method> Referring to Figures 3 to 7, the construction procedure for the simplified bridge deck slab connection method according to the embodiment of the present invention will be explained. Note that the simplified bridge deck slab connection method according to the embodiment of the present invention is applicable even when bridge expansion joints are already installed. Therefore, Figures 3 to 7 include illustrations of cases where existing bridge expansion joints are installed. However, if there are no existing bridge expansion joints installed, the removal of such expansion joints is not necessary.

[0031] Figure 3 is an explanatory diagram showing the state in which an existing bridge expansion joint is installed, Figure 4 is an explanatory diagram showing the state in which the PCa connecting panel 10 is being prepared for installation, Figure 5 is an explanatory diagram showing the state in which the PCa connecting panel 10 has been installed, Figure 6 is an explanatory diagram showing the process of pouring (filling) infill material after the PCa connecting panel 10 has been installed, and Figure 7 is an explanatory diagram showing the process of applying surface material (asphalt, concrete, various precast members such as precast concrete slabs, etc.). In the following explanation, the target for fixing the PCa connecting panel 10 is the deck slab 20, but depending on the structure of the bridge, the PCa connecting panel 10 may be fixed to other road structures instead of the deck slab 20.

[0032] The construction procedure for the simplified bridge deck connection method described below also includes the case where an existing bridge expansion joint exists. In this regard, the simplified bridge deck connection method of the present invention aims to prevent unnecessary damage to the existing bridge deck 20 and substructure, etc., caused by chipping work with breakers, etc., when removing the existing bridge expansion joint, and to reduce the noise generated in conjunction with the removal work of the bridge expansion joint.

[0033] However, if an existing bridge expansion joint exists, the simplified bridge deck connection method according to the present invention cannot be applied unless this bridge expansion joint is removed. The simplified bridge deck connection method according to the present invention can achieve the above-mentioned objectives of the present invention after the bridge expansion joint has been removed. Therefore, the case in which an existing bridge expansion joint exists is also explained, and the step of removing this existing bridge expansion joint is a necessary step for applying the simplified bridge deck connection method according to the present invention thereafter, and therefore does not contradict the objectives of the present invention.

[0034] <Construction Procedure> As shown in Figure 3, if an existing bridge expansion joint exists, it is necessary to remove it. Therefore, the existing bridge expansion joint is removed by chipping work using a breaker or the like. The chipping work is to secure space for installing the PCa connecting panel 10. Once the chipping work is completed, as shown in Figure 4, the lower part of the anchor reinforcement (reinforcement bars 32) that anchors the existing bridge expansion joint to the deck slab 20 remains in the deck slab 20. If there is no existing bridge expansion joint, chipping work is not necessary, but it is necessary to remove the surface material and to create space for installing the PCa connecting panel 10 (box cutting work).

[0035] In this state, as shown in Figure 5, the PCa connecting panel 10 is installed in the lower part of the space formed by the chipping work, and the PCa connecting panel 10 is connected to the deck slab 20 using reinforcing anchors 13. Next, as shown in Figure 6, the infill material 14 is poured (filled), and as shown in Figure 7, the surface material 40 (asphalt, concrete, various precast members such as precast concrete slabs, etc.) is installed on top of the PCa connecting panel 10 to complete the bridge structure.

[0036] As shown in Figure 6, when filling the gaps in the PCa connecting panels 10 with a filler material 14, joint material 15 is installed in the area where the second waterproofing mechanism 34 was removed. Also, as shown in Figure 7, when installing a surface material 40 (such as asphalt, concrete, or various precast members like precast concrete slabs) on top of the PCa connecting panels 10, waterproof material 50 is installed between the PCa connecting panels 10 and the surface material 40.

[0037] In Figures 5 to 7, the anchor bars (reinforcement bars 32) of the bridge expansion joint left in the deck slab 20 and the joint material 15 to be installed after the second waterproofing mechanism 34 of the bridge expansion joint are removed are shown. However, when a new bridge structure is constructed using PCa connecting panels 10, and when the surface material 40 is repaired or replaced while the PCa connecting panels 10 are already installed, the remaining reinforcement bars 32 and joint material 15 do not exist.

[0038] <Construction Procedure / When installing new precast concrete (PCa) connecting panels> When applying the simplified deck slab connection method to the embodiment of the present invention during bridge construction, as shown in Figure 5, the PCa connection panels 10 are installed and fixed to the deck slab 20 using reinforcing anchors 13. Then, as shown in Figure 6, a filler material 14 is poured into the gaps of the PCa connection panels 10. Finally, as shown in Figure 7, a surface material 40 (such as asphalt, concrete, or various precast members like precast concrete slabs) and a waterproofing material 50 are applied to the top of the PCa connection panels 10 to complete the bridge structure.

[0039] <Construction Procedure / When Repairing or Replacing Surface Material> Regardless of whether it is a bridge structure or not, road surface materials 40 (such as asphalt, concrete, and various precast members like precast concrete slabs) wear down and get damaged due to vehicle traffic, requiring periodic repair work. With the simplified deck slab connection method according to the embodiment of the present invention, if a bridge pier structure has already been constructed, only the surface material 40 (such as asphalt, concrete, and various precast members like precast concrete slabs) needs to be removed, and new surface material 40 (such as asphalt, concrete, and various precast members like precast concrete slabs) and waterproofing material 50 need to be installed. Therefore, construction becomes easier, the construction period can be shortened, and repair costs can be reduced.

[0040] <Advantages compared to conventional technology> The present invention aims to promote the widespread adoption of jointless construction in bridge structures by simplifying the connection of deck slabs. Therefore, the simplified deck slab connection method according to the present invention uses concrete panels (PCa connection panels) manufactured in a grid pattern (well-frame shape), thereby simplifying the reinforcement work and reducing the amount of filler material to be poured. Furthermore, a non-shrinkable filler material (for example, non-shrinkable mortar) may be used as the gap-filling material 14.

[0041] This makes it possible to easily achieve quick and reliable construction, thereby eliminating various obstacles to jointless bridge structures and enabling their widespread adoption. Furthermore, maintenance of the bridge structure will be limited to replacing or repairing the surface material applied to the surface, significantly reducing maintenance costs compared to bridge structures using conventional bridge expansion joints. In addition, it can improve vehicle drivability and the watertightness of the bridge structure. Moreover, if a non-shrinkable filler material is used as the infill material 14, a mobile vehicle for pouring the ultrafast-setting concrete will not be required, further reducing construction costs. [Explanation of symbols]

[0042] 10 PCa connecting panels 11 Reinforcement bars 12 Concrete 13 Reinforcement anchor 14. Filling material 15. Joint material 20 Floor slab 30 Telescopic device body 31 Main body 32 Reinforcement bars for the expansion joint body 33. First waterproof mechanism 34. Second waterproof mechanism 40 Surface material 50 Waterproof material

Claims

1. A method for constructing a bridge structure by connecting deck slabs in a bridge without using a bridge expansion device, A step of fixing the connecting panel to the road structure by inserting reinforcing anchors through the connecting panel; A step of placing filler material in the gaps of the connecting panels; applying a surface material to the top of the connecting panel; A simple connection method for deck slabs in a bridge, comprising:

2. The connecting panel is made of a PCa panel.

2. A simple connecting method for deck slabs in a bridge according to claim 1.

3. When repairing a bridge structure constructed through the above steps, The connecting panel is left in place, and only the surface material is repaired or replaced.

3. A simple connecting method for deck slabs in a bridge according to claim 1 or 2.

4. If a bridge expansion device has already been installed, After removing the bridge expansion device, A step of fixing the connecting panel to the road structure by inserting reinforcing anchors through the connecting panel; A step of placing filler material in the gaps of the connecting panels; and applying a surface layer to the upper portion of the connecting panel.

3. A simple connecting method for deck slabs in a bridge according to claim 1 or 2.

Images