JP2543004B2 - Expansion joint structure of bridge structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvement of expansion joints for road bridge structures in rivers, valleys, elevated roads and the like.

[0002]

2. Description of the Related Art Conventionally, in a bridge with a short span and a small amount of expansion and contraction, the asphalt is used to make the paved surface continuous.
Cutting joints are used that flatten the road surface, improve the running performance of the wheels, and absorb deformation.

However, these ideas have recently been developed,
There has been proposed an expansion joint called a buried joint, which is devised in structure and material so as to absorb a larger deformation. The feature of this buried joint is that asphalt mixture, binder and bone with the same properties as the pavement layer 2 are provided in the pavement cutouts at the ends of the bridge deck 1 facing each other with a play gap as shown in FIG. By laying the composite material layer 3 made of a material flush with the pavement surface, the displacement of the bridge is absorbed and the continuity of the road surface is secured.

[0004]

However, although this type of expansion joint has many advantages, it can be stretched when the asphalt mixture or the composite material layer 3 and the floor slab 1 or the pavement layer 2 are not sufficiently adhered to each other. Pavement layer 2 and composite material layer 3 when in the state
In many cases, a crack 4A is generated at an interface 4 between the pavement layer 2 and the rainwater, and the cracks expand due to repeated freezing and thawing in winter, and the pavement layer 2 often loses its integrity and is damaged. In particular, when the asphalt pavement layers before and after are newly laid and younger, the interface cracks are likely to occur.

Therefore, in order to increase the elongation performance of the composite material layer 3 at a low temperature, it is possible to consider a means of lowering the viscosity of the binder in the composite material layer to prevent cracking. However, according to such means, as shown in FIG. 4, when the temperature is high such as in the summer, phenomena such as rut, unevenness and dragging due to the flow of the composite material layer 3 may occur, which is not suitable. The present invention is intended to solve such problems by the following points.

[0006]

In order to solve the above-mentioned problems, in the present invention, a composite material layer is formed on the pavement surface of the pavement layer in the pavement notch at the end of the bridge deck facing each other across the play space. In bridge expansion joints laid in the same plane, place a streak at the interface between the composite material layer and floor slab near the interface between the pavement layer and the composite material layer,
An expansion joint structure is provided in which a through-strip is arranged on the outside of this bar. And, preferably, the arrangement position of the trusses from the floor slab is 1/3 to 3 with respect to the average particle size of the aggregate in the composite layer.
The expansion joint structure has a height position of ½.

[0007]

[Function] By arranging the through streak at the interface between the pavement layer and the composite material layer and by arranging the through streak on the outside of the reinforcing bar, the composite material layer and the floor slab become more integrated, and the force in the tensile direction is Restrain the movement of the composite layer.

[0008]

EXAMPLE An example of the present invention will be described below with reference to FIG. First, a cutout portion for laying the composite material layer 3 is formed in the pavement layer 2 at the end portion of the floor slab 1 which faces the play gap 8 and faces each other. The gap plate 10 is covered in the play space 8,
The backup material 9 is inserted. Figure 1 shows composite layer 3
Although the state of being laid is shown, the composite material layer 3 portion is a cutout portion before laying.

Before laying the composite material layer 3 in the cutout portion, a streak 6 is provided in advance in the interface 5 between the composite material layer 3 and the floor slab 1 in the vicinity of the interface 4 between the pavement layer 2 and the composite material layer 3. Plural pieces are arranged, and through-holes 7 are welded and arranged on the outside of the bar 6. It is more preferable that the arrangement position of the through streaks is at a height position which is ⅓ to ⅔ of the average particle diameter of the aggregate 3 a of the composite material layer 3.

Next, the composite material layer 3 is laid in the cutout portion of the pavement layer 2 at the end of the floor slab 1 so as to be flush with the pavement surface of the pavement layer 2. The aggregate of the composite material forming the composite material layer 3 has an average particle size of 2
The binder 3b is preferably asphalt containing rubber or the like.

Thus, the expansion joint structure of the bridge structure is formed in which the reinforcing bar is arranged at the interface between the pavement layer, the composite material layer, the composite material layer near the interface and the floor slab, and the through bar is arranged outside the reinforcing bar. It

Next, in the expansion joint in which the composite material layer is laid flush with the pavement surface of the pavement layer in the pavement notch portion of the bridge deck slab end facing each other across the play space, a new structure according to the present invention is provided. The relationship between the amount of expansion and contraction and the load of an expansion joint having a conventional structure that does not use a bar or a through bar will be described with reference to FIG.

In this figure, the horizontal direction shows the amount of expansion and contraction in a tensioned state, that is, the elongation, and the vertical direction shows the force acting at each elongation. Comparing the elongation and load of the conventional structure (shown by the solid line) and the new structure (shown by the dotted line), it is shown that the load of the new structure is large and the deformation is restrained by the resistance of the anchor. It can be understood that this effectively acts on the integration of the interface. Further, in the conventional structure, an interface crack occurs and breaks when the amount of expansion and contraction is around 18 mm. However, with the new structure, there is no more than about 36 mm, which is twice the expansion / contraction amount of 18 mm at the time of interface cracking of the conventional structure. As described above, the absolute superiority of the new structure is clear.

[0014]

As described above, the present invention has the following effects. That is, since the reinforcing bar is arranged at the interface of the composite material layer and the floor slab in the vicinity of the interface between the pavement layer and the composite material layer and the through bar is arranged outside the reinforcing bar, the reinforcing bar is
Strengthening the integration of the composite material layer and the floor slab, the through-streaks placed together with the reinforcing bar, against the amount of expansion and contraction in the tensile direction of the floor
It restrains the movement of aggregate in the composite layer and does not cause cracks at the interface between the pavement layer and the composite layer. Especially, the height position of the thread through the floor slab should be one third of the average particle size of the aggregate in the composite layer.
When the thickness is set to 2/3, the interface between the floor slab and the composite material layer is firmly integrated, so that the effect is large.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a diagram showing the relationship between the amount of expansion and contraction and load of the present invention and a conventional example.

FIG. 3 is a sectional view showing a conventional example.

FIG. 4 is a cross-sectional view showing an inappropriate example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Floor slab 2 ... Pavement layer 3 ... Composite material layer 3a ... Aggregate 3b ... Binder 4 ... Interface between pavement layer and composite material layer 4A ... Cracks 5 ... Interface between composite material layer and floor slab 6 ... Rebar 7 ... through line 8 ... play space 9 ... backup material 10 ... gap plate

Claims (2)

(57) [Claims] 1. A pavement layer and a composite material layer in a bridge expansion joint in which a composite material layer is laid flush with a pavement surface of a pavement layer in a pavement cutout part of a bridge deck slab facing each other across a play space. An expansion joint structure for a bridge structure characterized in that a reinforcing bar is arranged at the interface between the composite material layer near the interface with and the floor slab and a through bar is arranged outside the reinforcing bar. 2. The arrangement position of the trusses from the floor slab is at a height position which is one third to two thirds of the average particle diameter of the aggregate in the composite layer. An expansion joint structure for a bridge structure according to 1.