JP2001271303A - Joint-section structure of road - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the joint-section structure of a road in which the generation of a partial remarkable stepped section having an effect on safety traffic can be prevented on a road surface positioned at the upper section of one even when one relatively generates land subsidence in the joining section of roads having different bearing mechanisms. SOLUTION: The joint-section structure of the road is positioned between a concrete subgrade 30a and a crushed-stone subgrade 10. A roadbed for the crushed-stone subgrade is composed of back-filled soil and sand, and is relatively weak. A steel plate 21 fixed onto the concrete subgrade 30a by an anchor 22 is projected horizontally towards the top face of the crushed-stone subgrade 10. Asphalt 11 is laid integrally on the top face of the subgrade.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint structure between adjacent roads which is generated when a road is extended or widened.

[0002]

2. Description of the Related Art For example, in a case where a road is widened while an existing road 1 existing on a sloping land can be used, for example, as shown in FIG. In other words, the widening is realized by constructing the widening road structure 2 independently of the existing road 1. The widened road structure 2 includes a support composed of a stake 3 and a girder 4 fixed to the ground, and a floor slab 5 mounted on the support and constituting a roadbed.

At this time, with respect to the boundary joint 6 between the existing road 1 and the ground thereof and the widened road structure 2, a shoulder of the existing road 1 and a valley-side slope following it are excavated, and then the excavated surface 7 is excavated. And a widening road structure 2, a retaining wall 8 for retaining the ground is constructed of cast-in-place concrete, and a space between the back surface of the retaining wall 8 and the excavated surface is backfilled with earth and sand.
It is performed by laying crushed stone on it and making it a crushed stone roadbed,
Thereafter, asphalt or the like is integrally formed on the surface layer of the backfilled portion 9 (the portion of the crushed stone roadbed 10), the upper surface of the retaining wall 8 (the portion to be the concrete roadbed 8a), and the floor slab 5 of the widened road structure 2. To form a pavement surface layer, thereby forming a widened road.

[0004]

As described above, the space behind the concrete retaining wall 8 (on the side of the existing road 1) is backfilled with sand or crushed stone, but the area to be excavated is wide and backfilled with earth and sand to join the boundary. Since the ground of the part 6 is constructed, the roadbed of the joint part 6 becomes soft. For this reason, the backfilling portion 9 sinks down with the passage of the vehicle after the completion of the widening work, that is, with the passing vehicle load. At this time, the widened road portion composed of the floor slab 5 does not sink much because it is firmly supported by the piles 3 and the like constituting the subgrade. It does not sink much because of the strong ground below (the ground that has not been excavated and backfilled).

[0005] For this reason, the retaining wall 8 has been used for many years.
At the boundary A between the part of the road and the road of the backfill part 7, there is a possibility that a significant step or crack may occur. Although not as large as the boundary A, a step or a crack may also occur at the boundary B between the road of the floor slab 5 and the road of the retaining wall 8 due to the difference in the support mechanism. The present invention focuses on the above points, and in a joint of a direct foundation on the original ground and a road where the strength of a subgrade portion supporting the road such as a backfill portion or a pile foundation is different, one of the two is relatively. It is an object of the present invention to provide a joint structure of a road that can prevent a significant local step from affecting a safe traffic on a road surface located above the ground surface even if the land subsidence occurs. .

[0006]

In order to solve the above-mentioned problems, the invention according to claim 1 of the present invention is a joint structure of a road which is a boundary of a road having different strengths of a supporting subgrade. In a joint structure of a road having a roadbed of at least one road formed of a concrete roadbed, a steel plate fixed to the concrete roadbed and projecting horizontally or substantially horizontally from the concrete roadbed toward the roadbed of the other road is provided. It is characterized by being provided at the bottom of the pavement surface layer.

Next, an invention according to claim 2 is a joint structure between a concrete roadbed and a crushed stone roadbed, which is fixed to the concrete roadbed and is horizontal or sloping from the concrete roadbed toward the crushed stone roadbed. A steel plate is provided at the bottom of the pavement surface layer that projects substantially horizontally. Since one of the roadbeds is made of concrete, a steel plate can be securely fixed to the roadbed and can be made to project horizontally. In addition, what is necessary is just to fix a steel plate to a concrete roadbed with an anchor bolt, for example.

Further, the invention according to claim 3 is a joint structure between the widened road and the existing road, wherein the joint is horizontally or substantially horizontally between the floor slab of the widened road and the roadbed of the existing road. The steel plate is provided at the bottom of the pavement surface layer. Further, even when a vehicle load is applied in a state where a step is generated between the roadbeds at the bottom of the pavement surface layer at the boundary, the steel plate is deformed so as to bend, thereby preventing a steep step from being formed on the pavement surface layer. You. That is, on the pavement surface, the slope is gentle along the direction facing the boundary, and the step is reduced.

[0009]

Next, a first embodiment of the present invention will be described with reference to the drawings. The same members and the like as those in the above-described conventional example are denoted by the same reference numerals and described.
In the present embodiment, similarly to the above-described conventional example, a case where an existing road 1 having an inclined surface is expanded by a widened road structure 2 will be described as an example. However, since the basic configuration of the road expanded by the road widening work is the same as the conventional example described above, the details are omitted, and the joint structure between the roads will be described below with reference to the drawings. I do.

That is, as shown in FIG. 2, the concrete roadbed 8a comprising the upper part of the retaining wall 8 is
Floor slab 5 and crushed stone roadbed 1 formed on the upper part of the joint
0 are arranged adjacent to each other. First, the construction of the joint structure of the road between the concrete base 8a and the crushed stone base 10 will be described with reference to FIG.

First, the portion of the crushed stone subgrade 10 near the concrete subgrade 8a is adjusted to a level substantially equal to the upper surface of the concrete subgrade 8a. Next, a leveling mortar 20 is laid on the upper surface of the concrete roadbed 8a and the crushed stone roadbed 10 at the position where the steel plate 21 is to be installed, thereby eliminating unevenness. Thereby, the lower surface on which the steel plate 21 is placed becomes flat. The reason for laying the leveling mortar 20 is that it is difficult to make the upper surface of the concrete roadbed 8a and the upper surface of the crushed stone bed 10 completely flush with each other, and since the upper surface of the crushed stone bed 10 necessarily has unevenness. It is. When the leveling mortar 20 is not laid, after the construction of the widened road is completed, when a vehicle load or the like is applied to the road surface 23, the steel plate 21 is constantly owing to the unevenness of the crushed stone roadbed 10 side on the lower surface of the steel plate 21. It is not preferable because it easily swings and deforms.

Next, the unconsolidated leveling mortar 20
The steel plate 21 is placed on the concrete base plate 8a, and the steel plate 21 is fixed to the concrete roadbed 8a by the anchor 22. In the anchor 22 shown in FIG. 1, an anchor bolt is screwed and fixed to a cylindrical body projecting from the concrete roadbed 8a, but the anchor configuration is not limited to this. Other known anchors may be employed.

Next, the joint of the road between the concrete subgrade 8a and the floor slab 5 will be described. Since there is a gap between the concrete roadbed 8a and the floor slab 5, the gap is closed with the joint material 24. In FIG. 2, reference numeral 25 denotes a joint receiving steel plate. Next, a steel plate 28 to which a steel plate slip stopper 26 has been welded in advance is attached above the joint material 24. At this time, it is attached so as to secure a gap between the concrete roadbed 8a and the floor slab 5.

Next, a mortar 27 is injected into the gap. In the present embodiment, the upper surface of the floor slab 5 is slightly attached so that the upper surface of the concrete roadbed 8a and the upper surface of the floor slab 5 are aligned. This is because the concrete roadbed 8a and the floor slab 5a, which are caused by the slip prevention effect of the steel plate 28 and the construction error,
The purpose is to eliminate the step between the two. Here, each of the steel plates 21 and 28 preferably has a thickness of 4.5 mm or more and 12 mm or less. This is because if the thickness is less than 4.5 mm, it may be deformed so as to be bent without being bent by the vehicle load. On the other hand, if the thickness exceeds 12 mm, the steel plate 21 does not bend due to the vehicle load, and the pavement may be broken by the steel plate.

The steel plate 21 is a steel plate 21 having a width of about 400 mm.
To 200mm. In addition, the steel plate 21
Are continuously arranged along the extending direction of the road. As described above, when the joints between the roadbeds are completed, the pavement material 11 such as asphalt is paved integrally with the upper surface of the roadbed to form the road surface 23.

Next, the operation and effect of the joint structure of the road between the concrete roadbed 8a and the crushed stone roadbed 10 having the above configuration will be described. In the concrete subbase 8a, since the subgrade is made of concrete and solid ground, the sedimentation due to vehicle load does not occur much, but the crushed stone subbase 1
In the case of 0, the roadbed is made of backfilled earth and sand, and the vehicle load causes secular settlement.

As a result, the concrete roadbed 8
There is a possibility that a step is generated between the road surface a and the crushed stone roadbed 10, and a local step is generated on the road surface 23 above the road. However, in the present embodiment, even if a step is formed between the concrete roadbed 8a and the crushed stone roadbed 10, the steel plate 21 is deformed so as to be bent by the vehicle load, so that the roadbed 8a, 1
Road surface 23 located above 0 (in FIG. 2, reference C).
The formation of local steps or cracks at joints on the road is prevented. That is, on the road surface 23, the roadbed 8
a, a gentle slope along the facing direction between the a and the 10 and the step on the road surface 23 is alleviated.

Note that the horizontal behavior due to the seismic motion also
The steel plate 21 covers the joint of the road between the roadbeds 8a and 10. Next, the operation and effect of the joint structure between the concrete subgrade 8a and the floor slab 5 having the above configuration will be described. The concrete subbase 8a and the floor slab 5 do not suffer much secular settlement because their subgrades are strong, but the retaining wall 8 and the widened road structure 2 are both independent and independent structures. There is a possibility of uneven settlement due to the difference in the support mechanism between the foundation and the direct foundation. In addition, the earthquake causes a horizontal displacement relative to both. Even with this horizontal displacement,
Since the steel plate 28 is provided, the concrete roadbed 8a and the floor slab 5
The occurrence of cracks and the like on the road surface 23 is prevented.

Here, as each of the steel plates 21 and 28, it is preferable to use a steel plate having a rough upper surface such as a striped steel plate. If the upper surfaces of the steel plates 21 and 28 are rough, the frictional force between the steel plates 21 and 28 and the asphalt as the pavement surface layer increases, and the adhesion of the asphalt to the steel plates 21 and 28 increases. This makes it difficult for the asphalt to peel off the steel plates 21 and 28 due to the load on the road surface 23 due to the braking and acceleration of the vehicle. This is effective when there is a lot of traffic.

In the above embodiment, the steel plate 21 projecting from the concrete roadbed 8a to the crushed stone base 10 is disposed on the upper surface of the crushed stone base 10, but the crushed stone is laid on the upper surface of the steel plate 21. May be. That is, the steel plate 21
May not necessarily be arranged on the upper surface of the crushed stone roadbed 10. However, in this case, it is preferable to lay crushed stone on the upper surface of the concrete roadbed 8a.

Next, a second embodiment will be described with reference to the drawings. Note that the same members and the like as those in the above embodiment will be described with the same reference numerals. In the present embodiment, similarly to the first embodiment, an example will be described in which the existing road 1 having an inclined surface is expanded by the widened road structure 2. However, as shown in FIG. 3, the retaining wall 8 is not constructed between the widened road structure 2 and the existing road 1, and between the excavated surface 7 on the shoulder side of the existing road 1 and the widened road structure 2. This is an example of a case where the concrete 30 is cast into the groove of the joint 6 of FIG.

In this case, the upper surface of the cast-in-place concrete 30 at the joint portion becomes the concrete roadbed 30a. The existing road 1 is a crushed stone roadbed 1a. As shown in FIG. 4, similarly to the first embodiment, the steel plate 21 fixed to the concrete roadbed 30a with the anchor 22 is protruded horizontally or substantially horizontally toward the crushed stone roadbed 1a. .

As a result, the occurrence of local significant steps and cracks which affect the safety traffic between the existing road 1 and the junction 6 on the road surface 23 is prevented. Other configurations, operations, effects, and the like are the same as those in the first embodiment. As for the joint between the concrete roadbed 30a and the floor slab 5, the concrete 30 is integrally fixed to the pile 3 and the girder 4 of the widened road structure 2 by being driven into the concrete. Edition 5
The steel plate 21 is not installed because there is no possibility of unequal settlement because the and are integrally supported by the pile foundation.

Next, a third embodiment will be described with reference to the drawings. In this embodiment, as shown in FIG. 5, the adjacent sub-bases are both concrete sub-bases 31a and 32, but the sub-base of one sub-base 31a is made of concrete and has high strength, and the road of the other sub-base 32 is used. This is the case where the strength of the subgrade made of the backfilled earth and sand is relatively low.

In this case, too, in order to fill in a step caused by a construction error between the roadbeds 31a and 32 and eliminate unevenness, a leveling mortar 20 is laid on a portion where the steel plate 21 is installed, and the steel plate 21 is placed thereon. Is installed, and the steel plate 21 is fixed to the concrete roadbed 30a on the side with relatively large roadbed strength by the anchor 22. As a result, the occurrence of significant local steps and cracks that affect the safety traffic between the existing road 1 portion and the backfill portion is prevented.

Other structures, operations, effects, and the like are the same as those in the first and second embodiments.

[0027]

As described above, when the joint structure of a road according to the present invention is employed, even if a step is generated between roadbeds over time, a local surface which affects safety traffic on the upper surface of the roadbed. There is an effect that significant steps and cracks hardly occur.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a conventional widened road.

FIG. 2 is an enlarged view illustrating a joint structure of a road according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of a widened road according to a second embodiment based on the present invention.

FIG. 4 is an enlarged view illustrating a joint structure of a road according to a second embodiment of the present invention.

FIG. 5 is an enlarged view illustrating a joint structure of a road according to a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Existing road 1a Crushed stone roadbed 2 Widening road structure 3 Pile 4 Girder 5 Floor slab 6 Joint 7 Excavation surface 8 Retaining wall 8a Concrete roadbed 9 Backfill part 10 Crushed stone roadbed 11 Pavement material 20 Leveling mortar 21 Steel plate (joint steel plate) Reference Signs List 22 anchor 23 road surface 24 joint material 26 steel plate slip stopper 27 leveling mortar 28 steel plate (steel plate) 30 concrete 30a concrete roadbed 31 concrete 31a concrete roadbed 32 concrete roadbed 33 roadbed

Continuing from the front page (72) Inventor Hideki Yoshitake 2-3-2 Uchisaiwaicho, Chiyoda-ku, Tokyo Inside Kawasaki Steel Corporation (72) Inventor Keisuke Shiota 2-3-2 Uchisaiwaicho, Chiyoda-ku, Tokyo Kawasaki Steel Co., Ltd. F term in the company (reference) 2D051 AC04 AF01 AF03 CA01

Claims (3)

[Claims] 1. The joint structure of a road, which is a joint structure of a road, which is a boundary of a road having different strengths of a supporting subgrade, and wherein at least one of the road bases is a concrete base. A jointed road structure comprising a steel plate fixed to a roadbed and projecting horizontally or substantially horizontally from the concrete roadbed toward the roadbed of the other road at a bottom portion of a pavement surface layer. 2. A joint structure between a concrete roadbed and a crushed stone roadbed, which is fixed to the concrete roadbed and projects horizontally or substantially horizontally from the concrete roadbed toward the crushed stone roadbed. Joint structure of road characterized by having provided. 3. A joint structure between a widened road and an existing road, wherein a steel plate is provided horizontally or substantially horizontally between a floor slab of the widened road and a roadbed of the existing road at a bottom portion of a pavement surface layer. A joint structure of a road characterized by the following.