JP7421466B2 - Concrete slab replacement method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a concrete deck replacement method employed in renewal work for concrete slabs on road bridges.

Replacement work is being carried out to address age-related deterioration of the reinforced concrete slab on the steel girder. In such renewal work, after the removed concrete plates are peeled off and removed from the steel girder top flange, precast plates manufactured at a factory (hereinafter referred to as PCa plates) are brought to the site and the removed concrete plates are replaced. The road bridge deck will be updated by installing PCa plates at the locations and joining them with the steel girders and other newly installed adjacent PCa plates.
Many methods have been proposed and implemented for transporting and erecting heavy PCa boards to the replacement location in the limited construction space of a road bridge, but none of them are effective in terms of construction speed, safety, and economy. There is still room for further improvement.

Methods for installing concrete plates include a method using a swing-type self-propelled crane vehicle (for example, Patent Document 1), and a method using a gate-type crane with legs and beams that have telescoping functions (for example, Patent Documents 2 and 3). , a gate-shaped construction device equipped with a cantilever for installation (for example, Patent Document 4) is known.

Japanese Patent Application Publication No. 06-306819 Jito No. 3027712 Publication Japanese Patent Application Publication No. 2016-098489 JP2004-232426A

However, the method using a rotating self-propelled crane truck is limited in the number of sites where it can be used because it requires a crane installation site where the outriggers of the crane truck can be extended sufficiently. For example, in the case of renewal work for a road bridge with a width of 10 m, the planar dimensions of the PCa board will be approximately 10 m x 2 m, and the height to the top of the boom of the swivel-type self-propelled crane vehicle used to erect it will be 20 - The length is approximately 30m, making it unsuitable for use where there are structures on the road surface, such as underpass truss bridges. Furthermore, when rotating the PCa board by about 90 degrees with a crane, a working radius larger than the longitudinal dimension of the PCa board is required, and there is a risk of contact accidents in an environment where other structures are in close proximity.

In the method using a gate-shaped construction device, the gate size must be large enough to allow the transportation trolley carrying the PCa board to pass through, so an increase in size is unavoidable and equipment costs increase. Furthermore, there are many legal regulations, such as the need for gate-type construction equipment to be inspected by the competent authorities, and there are many restrictions when it comes to floor slab renewal work, which requires shortening the construction period.

An object of the present invention is to provide a concrete floor slab replacement method that can solve the above problems. In particular, the present invention allows for efficient renewal of concrete deck slabs of road bridges with a relatively simple equipment configuration, and in particular allows necessary equipment to be placed within an area of one lane width, making it possible to overcome spatial constraints. The purpose of this project is to provide a concrete slab replacement method that can reduce the amount of damage.

In order to solve the above problems, one form of concrete floor slab replacement method according to the present invention is as follows:
Loading a removed concrete plate, which is a concrete plate removed from an existing concrete slab from a road bridge, onto a forklift and transporting it to a position where the removed concrete plate can be rotated;
After the transportation, the removed concrete plate is placed on a rotating cart and the direction is rotated by approximately 90 degrees;
Lifting a new concrete plate from a transport vehicle by a first gate-type lifting device of two gate-type lifting devices arranged apart from each other in the lane direction and moving it upward;
After moving the newly installed concrete plate upward, the removed concrete plate whose direction has been changed by approximately 90 degrees is lifted by the other second gate-type lifting device of the two gate-type lifting devices, moving it upward;
After the removed concrete plate is moved upward by the second gate-type lifting device, the rotating truck is moved directly below the first gate-type lifting device, and the new concrete plate is placed on the rotating truck. loading the new concrete plate, transporting it to a position where it can be rotated, and rotating the direction approximately 90 degrees;
The new concrete plate rotated approximately 90 degrees is transported by the forklift to a construction position and installed.

According to one embodiment of the concrete slab replacement method according to the present invention, the deck slab of a road bridge can be efficiently replaced. In particular, it is suitable for construction methods in which the floor slab is divided into multiple parts in the width direction and replaced because the necessary equipment group can be placed within an area of one lane width and the work can be carried out in an area of one lane width.

1 is a side view of equipment for the concrete slab replacement method according to the first embodiment of the present invention, as viewed in the road width direction x. FIG. 2 is a plan view of FIG. 1; FIG. 2 is a side view of the gate-type lifting devices 7a and 7b of FIG. 1 when viewed in the lane direction y. FIG. 2 is a side view of the gate-type lifting devices 7a and 7b of FIG. 1 when viewed in the road width direction x. FIG. 2 is a side view showing movement of the forklift 5 for floor slab removal in the concrete floor slab replacement method of FIG. 1 . FIG. 2 is a side view showing transportation of the concrete plate to a position where the concrete plate can be rotated by the forklift 5 loaded with the removed concrete plate 1a in the concrete slab replacement method of FIG. 1. FIG. FIG. 2 is a side view showing the replacement of the removed concrete plate 1a from the forklift 5 to the swing truck 8 in the concrete slab replacement method of FIG. 1. FIG. FIG. 2 is a side view showing a change in direction of the removed concrete plate 1a due to the rotation of the rotating cart 8 in the concrete slab replacement method of FIG. 1; FIG. 2 is a side view showing the suspension of a newly installed concrete plate 1b from a first gate-type lifting device 7a to a swing truck 8 in the concrete slab replacement method of FIG. 1; FIG. 2 is a side view illustrating the direction change of a newly installed concrete plate 1b due to the rotation of the rotating cart 8 in the concrete slab replacement method of FIG. 1. FIG. FIG. 2 is a side view showing the replacement of a newly installed concrete plate 1b from a rotating cart 8 to a forklift 5 in the concrete slab replacement method of FIG. 1. FIG. In the concrete slab replacement method shown in Fig. 1, the newly installed concrete slab 1b is transported to the slab renewal area on the road bridge by the forklift 5, and the removed concrete slab 1a is suspended onto the transport vehicle 4 by the second gate-shaped lifting device 7b. It is a side view showing a lowering. FIG. 2 is a side view showing the installation of a new concrete slab 1b in the slab renewal area on a road bridge by a forklift 5 in the concrete slab replacement method of FIG. 1;

Next, embodiments according to the present invention will be described based on the drawings.
FIG. 1 is a side view of equipment for the concrete slab replacement method according to the first embodiment of the present invention, as viewed in the road width direction x, and FIG. 2 is a plan view of FIG. 1.
The concrete floor slab replacement method of this embodiment can be employed in a construction method in which a floor slab is divided into multiple parts in the width direction and replaced. The construction method of dividing the floor slab into multiple parts in the width direction and replacing them can be performed with only one lane restricted, so it is a construction method that can minimize social losses caused by traffic congestion.

In Figures 1 and 2, 1 is the existing deck slab to be updated, and 1a is a concrete plate for one renewal section to be removed after dividing the existing slab 1 in the direction of the traffic lane (hereinafter referred to as "removed concrete plate 1a"). ), 1b is a newly installed concrete board for one updated section, such as a newly installed PCa board. When there is no particular distinction between the removed concrete board 1a and the newly installed concrete board 1b, they are sometimes simply referred to as "concrete boards." The width of the new concrete slab 1b is limited to about 2 m due to transportation constraints, so the length in the lane direction y of one updated section of the existing slab 1 is about 2 m to match the width of the new concrete slab 1b. It is said that

In the concrete floor slab replacement method of this embodiment, a forklift 5, a turning truck 8, and two gate-type lifting devices 7a and 7b are used as equipment.

The forklift 5 is equipment for loading removed concrete plates 1a for one updated section or newly installed concrete plates 1b for one updated section and transporting them in the lane direction y. The rotating cart 8 loads the removed concrete plate 1a or the newly installed concrete plate 1b delivered from the forklift 5 or the gate-type lifting device 7a, 7b, and turns the concrete plate 1a, 1b in a horizontal plane so that the orientation of the concrete plate 1a, 1b is approximately 90 degrees. This is equipment for rotation. The two gate-type lifting devices 7a and 7b respectively pick up the removed concrete plate 1a or the newly installed concrete plate 1b from the rotating cart 8 and the transport vehicle 4 and move it upward, and the removed concrete plate 1a and the newly installed concrete plate 1b are transferred to the rotating cart 8 and the transport vehicle 4, respectively. This equipment is used to move the removed concrete plate 1a or the newly installed concrete plate 1b downward in order to suspend and load the plate 1a or the newly installed concrete plate 1b. The two gate-type lifting devices 7a and 7b are arranged apart from each other in the lane direction y in the lane near the floor slab renewal site.

FIG. 3 is a side view of the gate type lifting devices 7a, 7b as viewed in the lane direction y, and FIG. 4 is a side view of the gate type lifting devices 7a, 7b as viewed in the road width direction x. As shown in these figures, the gate-type lifting devices 7a and 7b each have two posts 71, 71 that are driven up and down at the same time, and a beam section that is supported horizontally on the two posts 71, 71. 72. The beam portion 72 is provided with a hanging tool 73 for hanging the removed concrete plate 1a or the newly installed concrete plate 1b through a wire 74.

Next, the steps of the concrete slab replacement method will be explained.
First, as shown in FIG. 5, the forklift 5 moves on the road bridge 9 to a position near the removed concrete slab 1a, which is the target of updating the existing floor slab 1, and then moves the forklift 5 over the road bridge 9 to a position near the removed concrete slab 1a, which is the target of updating the existing floor slab 1. The removed concrete plate 1a is loaded onto the forklift 5.

Next, as shown in FIG. 6, the forklift 5 loaded with the removed concrete plate 1a is moved to a position where the concrete plate can be turned in front of the two gate-type lifting devices 7a and 7b. On the other hand, the transport vehicle 4 loaded with the new concrete slab 1b is transported to one of the two gate-type lifting devices 7a and 7b (in this embodiment, the one closer to the existing slab 1) The new concrete plate 1b is lifted up from the transport vehicle 4 by the first gate-type lifting device 7a and moved. Here, the lifting height of the new concrete plate 1b by the first gate-type lifting device 7a needs to be such that the forklift 5 can safely pass under the lifted new concrete plate 1b. After lifting the newly installed concrete plate 1b by the first gate-type lifting device 7a, the transport vehicle 4 is moved to the truck standby position.

On the other hand, as shown in FIG. 7, a swing truck 8 is placed near the existing floor slab 1 side of the forklift 5 loaded with the removed concrete plate 1a, and the removed concrete plate 1a is transferred from the forklift 5 to the swing truck 8. Next, as shown in FIG. 8, the orientation of the removed concrete plate 1a is changed by approximately 90 degrees by rotating the turning table of the rotating cart 8 loaded with the removed concrete plate 1a by approximately 90 degrees. Thereby, the longitudinal direction of the floor slab 1 is oriented along the lane direction.

Subsequently, the rotating cart 8 loaded with the removed concrete plate 1a is moved directly below the second gate-type lifting device 7b, and the removed concrete plate 1a is lifted upward from the rotating cart 8 by the second gate-type lifting device 7b. be lifted and moved. After that, as shown in FIG. 9, the swinging cart 8 is moved directly below the first gate-shaped lifting device 7a, and the newly constructed concrete plate 1b is lowered onto the swinging cart 8 by the first gate-shaped lifting device 7a. .

Next, as shown in FIG. 10, after moving the rotating cart 8 carrying the newly installed concrete plate 1b to a position where the newly installed concrete plate 1b can rotate, the rotating cart 8 is rotated approximately 90 degrees to remove the removed concrete plate. The orientation of 1a is changed to one that can be installed in the updated section of the road bridge 9.
Thereafter, as shown in FIG. 11, the waiting forklift 5 moves to the vicinity of the swing truck 8, and the new concrete plate 1b is transferred from the swing truck 8 to the forklift 5.

Next, as shown in FIGS. 12 and 13, the forklift 5 moves to the vicinity of the renewal section from which the removed concrete board 1a was removed, and installs the removed concrete board 1a in the renewal section. Meanwhile, the waiting transport vehicle 4 moves directly below the second gate-type lifting device 7b, loads the removed concrete plate 1a unloaded from the first gate-type lifting device 7b, and leaves the site. do.
As described above, the replacement of one updated section of the floor slab is completed, and the replacement work for the next updated section is performed in the same manner.

As explained above, according to the concrete floor slab replacement method of this embodiment, a relatively simple equipment configuration such as a forklift 5, a turning truck 8, and two gate-type lifting devices 7a and 7b is used to replace the floor slab. Replacement can be performed efficiently. In particular, since the necessary equipment group can be placed within an area the width of one lane, and work can be carried out within an area the width of one lane, this method is suitable for construction methods in which the floor slab is divided into multiple parts in the width direction and replaced.

In the above embodiment, the removed concrete plate 1a and the newly installed concrete plate 1b are rotated using the rotating cart 8 to change their orientation by approximately 90 degrees. However, for example, the distance between the posts 71 is It is also possible to install a gate-type lifting device or a swing-type erection device that is longer than the length in the longitudinal direction, and use this type of device to change the orientation of the removed concrete plate 1a and the newly installed concrete plate 1b. However, this type of equipment takes up a lot of space and cannot be accommodated in a single lane width area, making it unsuitable for construction methods in which the floor slab is divided into multiple parts in the width direction and replaced. Under these circumstances, it is appropriate to use the rotating cart 8 for rotating the floor slab 1.

Furthermore, in the above embodiment, among the two gate-type lifting devices 7a and 7b, the new concrete plate 1b is raised and lowered by the gate-type lifting device 7a that is closer to the slab renewal area, and the one that is farther away from the slab renewal area It was decided that the removed concrete plate 1a would be raised and lowered by the gate-type lifting device 7b in the floor slab renewal section, but conversely, the removed concrete plate 1a would be raised and lowered by the gate-shaped lifting device 7a closer to the floor slab renewal section. The newly installed concrete plate 1b may be raised and lowered by the gate-shaped lifting device 7b located further away.

1...Floor slab 1a...Removed concrete plate 1b...New concrete plate 4...Transport vehicle 5...Forklift 7a...First gate-type lifting device 7b...Second gate-type lifting device 8...Swivel truck 9...Road bridge

Claims (2)

Loading a removed concrete plate, which is a concrete plate removed from an existing concrete slab from a road bridge, onto a forklift and transporting it to a position where the removed concrete plate can be rotated;
After the transportation, the removed concrete plate is placed on a rotating cart and rotated approximately 90 degrees;
Lifting a new concrete plate from a transport vehicle by a first gate-type lifting device of two gate-type lifting devices arranged apart from each other in the lane direction and moving it upward;
After moving the newly installed concrete plate upward, the removed concrete plate whose direction has been changed by approximately 90 degrees is lifted by the other second gate-type lifting device of the two gate-type lifting devices, moving it upward;
After the removed concrete plate is moved upward by the second gate-type lifting device, the rotating truck is moved directly below the first gate-type lifting device, and the new concrete plate is placed on the rotating truck. loading the new concrete plate, transporting it to a position where it can be rotated, and rotating the direction approximately 90 degrees;
transporting the new concrete plate rotated approximately 90 degrees to a construction position using the forklift and installing it;
Concrete slab replacement method with The concrete floor slab replacement method according to claim 1,
A concrete floor slab replacement method further comprising: moving a transport vehicle directly below the second gate-type lifting device, and placing the removed concrete plate on the transport vehicle using the second gate-type lifting device.

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