JPS597365Y2 - Edge structure of concrete slab at road joint - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an end structure of a concrete slab at a road joint.

When constructing an expansion/contraction device at the joint of a road bridge such as a bridge or elevated road, a cutout step is formed at the end of the concrete slab.
A widely used method is to install an expansion joint member on top of the notched step and pour post-cast concrete. In this case, it is necessary to provide a dowel line at the notch step.

For this reason, conventionally, as shown in FIG.
After fixing the line b, a concrete slab C is cast to form a notch step d at the end, and post-cast concrete 'J-}e is poured into the notch step to make the joint. Although component f is installed,
There is a drawback that good construction cannot be performed because the U-shaped bar b becomes an obstacle when shaping the notch step d.

That is, when the end portion is notched to form the notch step portion d after the concrete slab C is cast, there is a disadvantage that the notch construction is difficult due to the U-shaped striations b and requires much time and labor.

In addition, if the box-cutting method is used, in which a formwork with a notched stepped portion d is formed in advance is temporarily installed and concrete is poured, the installation of the formwork becomes unstable because the U-shaped bar b becomes an obstacle. As a result, concrete cannot be compacted sufficiently after pouring, and the strength of the concrete near the notch becomes weaker, resulting in post-cast concrete.
Also, there is a concern that the load-bearing strength of the joint member f will be reduced.

Furthermore, each time a joint member is replaced or repaired, the end of the deck slab is removed by adding a layer of post-cast concrete, but since the slab is subjected to large impact vibrations during chiseling work, the entire end of the deck is removed. In particular, since these joint members are frequently replaced and repaired, there are more problems with the strength of the edge of the deck than in the past.

Furthermore, in many road bridges, multiple main girders (steel girders) are installed in parallel at predetermined intervals, and then a concrete slab is formed, but as mentioned above, the strength of the concrete at road joints is reduced. The concrete deck slab between each main girder has a particularly low load-bearing strength because it is not supported by the main girder.
There is a concern that cracks may occur when a large load is applied through the joint member.

In view of this, the present invention divides the end of the deck slab into an upper concrete layer and a lower concrete layer by means of stepped surface members extending in the road width direction, and transfers the load of vehicles passing through the road joint to the stepped surface members. This aims to improve the load-bearing strength of the deck edge at the road joint by distributing the load over a wide range in the road width direction, and in particular by transmitting the above-mentioned load to the main girder via the step surface member. It is.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be described below with reference to the drawings.

Reference numeral 1 denotes a stepped surface member which is installed in close contact with the bottom surface 3a and side surface 3b of the notched stepped portion 3 formed at the end of the pre-cast concrete floor slab 2, and is approximately L-shaped in cross section. The bottom side 1a of this stepped surface member 1 covers the entire bottom surface 3a of the notched step 3, and the anchor reinforcements 5 protruding from the back surface are attached to the pre-cast concrete slab 2, and the dowel reinforcements protruding from the surface. 6 is buried in the post-cast concrete 7 to connect the pre-cast concrete floor slab 2 and the post-cast concrete 7.

As shown in FIG. 2, this step surface member 1 has a plurality of through holes 8, 8, .
is drilled and extends in the width direction of the road, and the base 1a
The upper concrete layer, that is, the post-cast concrete 7
and a lower concrete layer, that is, a pre-cast concrete slab 2 located below the stepped surface member 1.

10 is post-cast concrete 7 with anchor bolt l-11
It is an expansion joint fixed to the upper layer, and a steel plate 10 is attached to the lower surface of a flexible expansion and contraction plate 10a made of an elastic material such as rubber.
b is fixed.

12 is the pavement placed on the pre-cast concrete slab 2;
13 is a main girder, and 14 is a distribution reinforcement.

The step surface member 1 is made by welding the anchor reinforcements 5 to the distribution reinforcements 14 in advance to fix the step surface member 1, and then pouring concrete to form the pre-cast concrete slab 2. This allows it to be fixed to the edge of the pre-cast concrete slab.

Therefore, this cross-sectional member 1 serves as a formwork for shaping the notch step 3 when concrete is poured, but since it is fixed to the distribution bars 14 by the anchor bars 5, it has good installation stability and is suitable for pouring concrete. The placed concrete can be sufficiently compacted, and a pre-cast concrete floor slab 2 with high strength can be obtained.

Further, the pre-cast concrete slab 2 and the post-cast concrete slab 7 are connected by the anchor bars 5 and dowel bars 6 of the step surface member 1, and are unified by the through hole 8 drilled in the step surface member 1. Since the parts are integrated with the same concrete 1, the fastening force between the two is strong.

Note that the stepped surface member is not limited to the L-shaped cross section as shown in FIG. 2, and its shape can be changed as appropriate.

For example, as shown in FIG.
A may be tilted, an inverted U-shaped dowel bar 16 may be erected thereon, and the gap 9 may be filled with a filler 17 such as rubber.

Further, when constructing a telescopic device having a structure in which end plates 18 and 18 are disposed opposite each other as shown in FIG. 4, a U-shaped step surface member 19 may be used.

When a U-shaped stepped surface member 19 is applied, the inner sides 19a, 19a of the stepped surface member are used as weir plates,
The end plate 18.
18 can be welded.

Furthermore, as shown in FIG. 5, only the bottom surface 3a of the notch step 3 may be covered with the step surface member 20.

In this case, when constructing the pre-cast concrete slab 2,
A formwork for forming the side surface 3b of the notched step part 3 is erected at the rear end of the step surface member 20, but the formwork can be attached to the dowel bar 6 of the step surface member 20. Because of its good stability, concrete can be compacted sufficiently.
Moreover, since the post-cast concrete 7 comes into direct contact with the pre-cast concrete slab 2, there is an advantage that the fastening force between the two is strong and the load-bearing strength of the road joint is increased.

Next, another embodiment of the road joint expansion/contraction device constructed on the step surface member 1 having an L-shaped cross section shown in FIG. 1 will be described with reference to FIG. 6.

Reference numeral 21 denotes a corrugated end plate which is meshed with a meshing clearance 22, and an anchor member 23, 23 protruding from the back surface is connected to the dowel bar 6, and the bottom side of the stepped surface member 1 is connected to the lower part of the back surface. A weir plate 24 erected thereon is welded.

The corrugated end plate 21.21 has a flexible U-shaped sealing member 25 baked on its inner surface and a bottom plate 2 at its lower end.
6 is fixed.

Since the bottom side 1a of the step surface member 1 is smooth, the weir plate 24 can be erected without creating a gap between it and the bottom side, and prevents concrete leakage when pouring concrete 7 is poured. There is no risk of this occurring.

Moreover, since the height of the upper edge of the weir plate 24 is approximately constant,
The height of the corrugated end plate 21 welded to the upper part of the weir plate can be easily adjusted.

In addition, the pre-cast concrete slab 2 has high strength because the concrete can be sufficiently compacted by installing the step surface member 1, and therefore the load-bearing strength of the road joint is higher than that of the conventional one. It will be greatly improved.

As described above, according to the end structure of the concrete slab according to the present invention, by installing the step surface member in the notch step, the pre-cast concrete slab can be sufficiently compacted. Therefore, the strength of the end of the floor slab is significantly improved compared to the conventional one, and it is therefore possible to construct an expansion and contraction device with high load-bearing strength.Also, since the notch step part is widened by the step member, it is possible to construct an expansion and contraction device. It is easy to construct and can be constructed with high precision. Furthermore, when replacing or repairing this expansion device, even if the two-part concrete layer is chiselled, the effect of this chisel work will be on the lower concrete layer, so there is no need to re-construct the entire end of the slab. This has the excellent effect of making it easier to replace and repair the expansion and contraction device.

In particular, according to the structure of the present invention, the load from the road surface is dispersed over a wide range in the width direction of the road by the step surface member, so that the load-bearing strength of the end of the floor slab can be improved.

[Brief explanation of drawings]

The drawings illustrate the embodiment of the present invention, and FIG. 1 is a sectional view in the bridge length direction showing the end structure of the concrete deck, FIG. 2 is a perspective view of the step surface member, and FIGS. 3 to 5 are A cross-sectional view in the bridge length direction showing another example of the end structure of a concrete slab. Figure 6 is a cross-sectional view in the bridge length direction showing another example of the road joint expansion/contraction device constructed at the end of the concrete slab shown in Figure 1. The perspective view and FIG. 7 are cross-sectional views in the bridge length direction showing the end structure of a conventional concrete slab. 1, 15, 19.20...Stepped surface member, la,
15a...Base, 1b...Side, 2.
...Pre-cast concrete floor slab, 3...Notch step, 3a...Bottom surface, 3b...Side surface,
5... Anchor bar, 6.16... Gibel bar, 7... Post-cast concrete, 8...
・Through hole, 10... Expansion joint, 12...
・Pavement, 13...Main girder.

Claims (1)

[Scope of utility model registration request] A cut-out step consisting of a bottom and side surfaces is formed at the end of the slab at the road joint, and concrete is poured into the cut-out step.
At a road joint where the end of the slab is formed by an upper concrete layer and a lower concrete layer, the entire bottom surface of the notched step is covered with a plate-shaped step surface member extending in the road width direction, and this step is An edge of a control slab at a road joint portion, characterized in that an upper concrete layer and a lower concrete layer are separated as a face member, and anchor reinforcements protruding from the stepped face member are buried in the lower concrete layer. Departmental structure.