JPS6346497Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an axial force transmission device between old and new deck slabs used in a method for replacing composite girder decks forming the road surface of road bridges and the like.

Road bridges include composite girders and non-composite girders.

The former composite girder consists of a deck slab and a steel main girder that supports the deck slab, and has a structure that resists the loads of moving vehicles, etc., while the latter non-synthetic girder relies only on the strength of the main girder itself. It has a structure that can withstand the above load.

In recent years, with the aging of such concrete floor slabs, there has been an increase in the number of floor slab renovations, that is, floor slab replacement work. When performing this replacement work, if the deck is made of the non-synthetic girder mentioned above, the main girder itself has sufficient strength, so it is possible to perform the replacement work one by one using methods such as one-sided traffic. be.
On the other hand, in the case of composite girders, where the deck slab and the main girder supporting it form an integral structure to resist loads, due to the unique structure of the composite girder, there is a problem of insufficient strength of the main girder when replacing the deck slab. This is naturally expected. For this reason, it is considered extremely difficult to perform floor slab replacement work while the building is open to traffic. Therefore,
Previously, unless the site had sufficient width for repeated construction, methods such as constructing a so-called emergency bridge across the replacement work section, or securing a detour and temporarily constructing a branch road were used. The floor slabs were being replaced while dealing with traffic.

In such a conventional method, even if the emergency bridge is constructed, it is a fairly large-scale bridge construction work that spans the replacement work section, which requires a great deal of effort and cost, and depending on the replacement work section, There were problems such as it was often difficult to even find a detour.

Therefore, the applicant has already proposed a method for replacing composite girder slabs that solves these problems. As shown in Figure 1 a, b and Figure 2, this construction method involves closing a certain section of the old slab 2 on the main girder 1 to traffic, for example at night, and completing the replacement work in the target section during that time. Only the section L that can be removed is removed, and then a concrete slab 3 is laid to form a new floor slab 6. An axial force transmitting device 8 is set which transmits stress in the axial direction between the old and new floor slabs by applying pressure in a direction in which both end faces are separated from each other, and a lining plate 9 for vehicles to run is placed on the old and new floor slabs. The road will be opened to traffic.

This has had the remarkable effect of essentially eliminating large-scale traffic management methods such as securing detours and constructing emergency bridges, which require a great deal of effort and expense. Note that 4 and 5 are joint concrete, and 7 is a bearing plate.

This method of replacing composite girder deck slabs was able to achieve the above objectives, but when implementing this replacement method, it is necessary to 8, a hydraulic jack was conventionally used, but it had the following problems. That is,
The function that the axial force transmission device 8 between the old and new floor slabs 6, 2 should have is that the pressure that separates the floor slabs 2, 6 from each other due to the load of the vehicle itself running on the lining board 9, repeated loads, etc. It is desirable to maintain a constant pressure on both the old and new floor slabs 6, 2 without changing each time, and to keep the distance A between the old and new floor slabs 6, 2 constant at all times, but in general In the case of a hydraulic jack, it is difficult to control and manage the above-mentioned functions, and there are concerns about its reliability. In order to prevent the distance A between both slabs 6 and 2 from decreasing, the pressure of the axial force transmission device 8 can be increased, but if it is increased too much, too much pressure will be applied to both slabs 6 and 2. That much,
This may not only reduce the strength of both slabs 6 and 2, but also cause edge chips and cracks in the concrete layer.

In addition, the axial force transmission device 8 simply includes the floor slab 2,
Not only does stress act in the tree direction between 6, but also stress due to the passage of vehicles, etc. acts in the longitudinal direction.
Countermeasures against this stress are also required.

The present invention has been made in consideration of the above points, and its object is to provide an axial force transmission device between old and new deck slabs which can maintain a constant pressure separating the old and new deck slabs, and a constant deck slab spacing, even when subjected to the load of the running vehicle itself and repeated loads, has a simple mechanism which is unlikely to malfunction and is easy to operate and handle, and has sufficient strength to withstand the vertical load caused by the running vehicle.

Hereinafter, the present invention will be explained based on an embodiment shown in the attached FIGS. 3 and 4.

In the figure, reference numerals 10 and 11 are a pair of bearing pressure plates arranged opposite to each other, and both bearing pressure plates 1
One of the bearing pressure plates 10 of the bearing pressure plates 10 and 11 is provided with a fixed cylinder 12 that protrudes from this bearing pressure plate 10 toward the other bearing pressure plate 11. This fixed cylinder 1
A male thread 12a is formed on the outer peripheral surface of 2.
Furthermore, a movable cylinder 13 is attached to the fixed cylinder 12 and has a female thread 13a on its inner peripheral surface that is screwed into the male thread 12a of the fixed cylinder 12. Further, the other bearing pressure plate 11 is provided with a connecting member 14 having a circular cross section and slidably fitting into the fixed cylinder 12. Note that the length of this connecting member 14 is shorter than the length of the fixed cylinder 12 (about half in the embodiment).
It is formed. A fluid pressure cylinder 15, such as a hydraulic jack, is set within the fixed cylinder 12 for applying pressure in a direction to separate the bearing pressure plates 10, 11 from each other. This fluid pressure cylinder 1
5 is equipped with a cylinder body 15a and a cylinder rod 15b that expands by fluid pressure sent from a pump unit (not shown). Connecting member 14
are set so as to abut on the end surfaces 14a of the respective parts. Note that there is a notch 12 that opens upward in the peripheral wall of the fixed cylinder 12 at a position near the bearing pressure plate 10.
b is provided, and from this notch 12b, the fluid introduction part 15c of the fluid pressure cylinder 15 is connected to the fixed cylinder 1.
It is projected outward (above) from 2. Moreover, on the upper outer surfaces of both the bearing pressure plates 10 and 11, new and old floor slabs 16 and 17 to which mutual axial force is to be transmitted are provided.
Flange plates 18 and 19 extending toward the upper surface side are provided, and both flange plates 1
Bolts 20 are screwed into bolts 8 and 19 for adjusting the vertical position of the entire axial force transmission device by bringing their tips into contact with the upper surfaces of the floor slabs 16 and 17, respectively. Note that the axial force transmission device is indicated by the symbol G as a whole.

When using the device for transmitting axial force between the old and new floor slabs according to the present invention configured as described above, first, the axial force should be adjusted according to the distance between the end faces of the floor slabs 16 and 17 to which the axial force is to be transmitted. After adjusting the spacing between the pressure plates 10 and 11 by rotating the movable cylinder 13, they are set between the floor plates 16 and 17 as shown in FIG. Here, the vertical position of the bearing pressure plates 10 and 11, that is, the vertical position of the axial force transmission device G, is adjusted by bolts 20.

After the axial force transmission device G is set in this way, fluid (pressure oil, etc.) is then sent from the fluid introduction part 15c to the fluid pressure cylinder 15, and the cylinder rod 15b is extended so that both bearing pressure plates 10 and 11 are moved away from each other. Apply pressure. and,
In this state, the movable cylinder 13 is rotated,
The movable cylinder 13 is moved until one end (the left end in the figure) comes into contact with the inner surface of the bearing plate 11. When one end of the movable cylinder 13 comes into contact with the inner surface of the pressure plate 11, the movable cylinder 13 and the fixed cylinder 12 cause the pressure plates 10,
11 is maintained, the supply of fluid to the hydraulic cylinder 15 is stopped.

Then, a lining board (not shown) is passed between the floor slabs 16 and 17 and set, and traffic processing is carried out in the same manner as in the past.

In the above, since the movable cylinder 13 is attached to the fixed cylinder 12 by screw connection, it does not move in the axial direction except when the movable cylinder 13 is rotated. Therefore,
The distance between the two bearing pressure plates 10, 11 is reliably maintained, and as a result, the axial force of the floor slabs 16, 17 is reduced by the two bearing pressure plates 10, 11.
11, a fixed cylinder 12, and a movable cylinder 13. And the fluid pressure cylinder 1
Even if the fluid supply to cylinder 5 is stopped, the axial force is reliably transmitted in this way.
No need for hydraulic management, etc. in step 5, making on-site management work easier. Further, the setting work of the axial force transmitting device G can be done by first applying the necessary pressure to both bearing pressure plates 10 and 11 using the fluid pressure cylinder 15, and then rotating and positioning the movable cylinder 13. It is an extremely easy task to complete. Note that the bearing plate 11 is provided with a connecting member 14, and the end side of the connecting member 14 is fitted into the fixed cylinder 12, so that the axial force transmitting device G absorbs the longitudinal load caused by the running of the vehicle. Demonstrates sufficient strength against

By the way, this axial force transmission device G is
When setting between the end faces of 6 and 17, the old floor slab 17
If the cut surface of the cut surface is uneven due to the cutting method or quality of the work,
For example, as shown in FIG. 5, the end face of the old and new slab 17 is covered with a steel formwork 21 having a U-shaped cross section and an injection hole 21a and an exhaust hole 21b. In the meantime, after fixing the formwork 21 by injecting and filling caulking material 22 such as epoxy resin through the injection hole 21a, the axial force transmitting device G according to the present invention may be set. In this case, the end surfaces of the new floor slab 16 can generally be finished with a certain degree of precision in a factory, etc.
Although it is not necessary to provide the formwork 21, it may be provided in the same manner as the old floor slab if necessary. In addition, in FIG. 5, 23 indicates a sealing material.

As described in detail above, according to the present invention, it is possible to constantly apply a constant pressure to both the old and new deck slabs to which axial force is to be transmitted, and even when large stress is applied, the gap between the two deck slabs is Since the spacing can always be kept constant, it exhibits the ideal function as an axial force transmission device, and it is extremely easy to set up on site, and does not require hydraulic control, etc., improving work efficiency on the work site. Furthermore, it has excellent effects such as having sufficient strength against longitudinal stress caused by running a vehicle, and having a particularly simple structure and being able to be manufactured at a low cost.

[Brief explanation of the drawing]

Figures 1a, b and 2 are cross-sectional views, plan views, and cross-sectional views showing how a conventional axial force transmission device is used, and Figures 3 and 4 are cross-sectional views showing an embodiment of the present invention. and a plan view, and FIG. 5 is a sectional view of the formwork fixed to the end face of the old floor slab. 10, 11... Bearing plate, 12... Fixed cylinder body, 1
2a...Male thread, 13...Movable cylinder, 13a...
Female thread, 15...Fluid pressure cylinder.

Claims (1)

[Scope of utility model registration request] A pair of bearing pressure plates facing each other, a fixed cylinder protruding from one of the bearing pressure plates toward the other bearing plate, and a fixed cylinder that is attached to the fixed cylinder by screw connection and fixed. a movable cylindrical body movable in the axial direction of the cylindrical body, and a movable cylindrical body set between the two bearing plates,
An axial force transmission device between the new and old deck slabs, which is equipped with a fluid pressure cylinder that applies pressure in the direction of separating both bearing pressure plates from each other.