JPS6233761Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a road joint structure in which a roadbed layer is formed on the roadbed, and a concrete slab layer is formed on the roadbed layer.

Concrete pavement, which consists of a subbase layer and a concrete slab layer, is widely used as road pavement because it absorbs traffic loads through the bending resistance of the concrete slab layer, and the burden on the subbase layer and subgrade is small. . However, concrete pavement allows the concrete slab layer to expand and contract due to temperature differences, so it is necessary to provide joints at certain distances, and these joints have the disadvantage of impairing the running performance of vehicles and the durability of the pavement. be. In other words, in conventional joints, whether they are contraction joints or expansion joints, the joint material is injected after forming a linear gap perpendicular to the longitudinal direction of the road. If the joint gap is widened, a linear groove will be formed in the joint area and the tire will fall in. To prevent this tire from falling in, set the top surface of the joint material to the maximum joint. If the joint material is set to match the road surface during the clearance, the joint material will bulge up on the road surface when the joint clearance is at its minimum, making it impossible to always obtain good vehicle running performance in either case.

On roads, not only cracks occur in the concrete slab layer due to the impact caused by passing vehicles, but also the impact and the transport load of passing vehicles cause the roadbed layer to cave in and the concrete slab layer to be damaged. There is. That is, the roadbed layer is generally formed by laying earth, sand, fine stones, etc. on the roadbed, but it is soft and has low load-bearing strength. Therefore, when the roadbed layer is repeatedly subjected to large loads through the concrete slab layer due to the passage of vehicles, a phenomenon of cave-in will gradually occur directly under the joints formed in the concrete slab layer. There is a problem that the subgrade layer is damaged due to large bending stress in the depressed area.

As a means to solve these problems, the present invention provides a roadbed layer in which earth and sand, fine stones, etc. are spread over the roadbed.
In a road in which concrete slab layers with joints provided at predetermined intervals are formed on the subbase layer, the concrete slab layers have joints and opposing surfaces are substantially perpendicular, and the joints have a corrugated shape in the longitudinal direction. A corrugated joint gap is formed by the two opposing surfaces, and a joint material is injected into the joint gap while allowing the top surface to cave in as the joint gap expands, and the top surface of this joint material provides a road joint structure characterized in that the height is set to substantially match the surface height of the concrete slab layer at the time of minimum clearance.

In the case of the joint structure described above, the top surface of the joint material at the minimum clearance matches the surface height of the concrete slab layer, and the top surface of the joint material only collapses as the joint clearance expands, so the joint does not reach the street. There are no problems with deterioration of vehicle driving performance or damage to joint material due to piled up timber. Even when the joint material is depressed, the grooves caused by the depression are wave-shaped, so
Vehicle tires pass through the joint from the convex part of one facing concrete slab layer to the convex part of the other concrete slab layer without substantially falling into the groove, improving running performance. There is no problem and no impact is applied to the concrete slab layer when passing through.

Embodiments of the present invention will be described below with reference to the drawings.

<Example 1> This example is a case where the present invention is applied to an expansion joint as shown in FIG. Reference numeral 1 denotes a road, in which a roadbed layer 2 is formed by laying a series of earth, sand, fine stones, etc. on a roadbed (not shown), and expansion joints 6 are provided at predetermined intervals on the roadbed layer. Plate layers 3 and 3 have been placed. The concrete slab layers 3, 3 have expansion joints 6, opposing opposing surfaces 5, 5 are substantially perpendicular, and both opposing surfaces 5, 5 are corrugated in the longitudinal direction of the joint, that is, they form recesses 3a at a predetermined pitch. The convex portions 3b are formed alternately, and the concave portions 3a and convex portions 3 of each other are formed alternately.
A wave-shaped joint gap is formed by making the b and b face each other. The expansion joints 6 are filled with injection joint material 7 to a depth of about 25 mm from the surface of the concrete slab layer 3.
Sawdust layer 8 from the poured joint material to a depth of about 15 mm
Furthermore, the molded joint plate 10 extends from the sawdust layer to the top surface of the roadbed layer 2 (about 200 mm in height).
It is formed by. 11 is a slip bar,
11a is a chair, and 11b is a cap.

The expansion joint 6 does not necessarily limit the depth or height of the injection joint material 7, the sawdust layer 8, and the molded joint plate 10 to the above values, and in some cases, the depth or height of the molded joint plate 10 or the sawdust layer 8 may be In some cases, only the injection joint material 7 is used as a water-stopping means without any water sealing.

The injection amount of the injected joint material 7 is adjusted so that when the concrete layer 3 expands and the width of the expanded joint 6 becomes the minimum, the upper surface of the injected joint material 7 matches the surface height of the concrete layer 3. adjust. Therefore, when the concrete slab layer 3 shrinks, that is, when the joint gap expands, the injection joint material 7 is lowered from the surface of the concrete slab layer 3, and a groove is formed in the expansion joint 6. However, since the concrete slab layer 3 has the grooves and engages in a wave shape, the tires of passing vehicles always come into contact with the road surface from one convex part 3b of the concrete slab layer to the other convex part 3b. It passes over the grooves while moving, and does not vibrate due to tires falling or the like. In addition, since the concrete slab layer 3 and the roadbed layer 2 are not subjected to impact due to tire depression, cracks in the concrete slab layer 3 and depression of the roadbed layer 2 do not occur.

<Example 2> This example is shown in FIG. 2 and is a case where it is applied to a contraction joint. Reference numeral 12 denotes a road, in which a concrete slab layer 13 is cast on the roadbed layer 2, and contraction joints 15 are formed in the upper part of the concrete slab layer. The contraction joints 15 are formed by forming the facing surfaces 14, 14 of the concrete slab layer 13 substantially vertically and in a waveform (unevenness) in the longitudinal direction of the joints, so that the concave portions 13 of each other
A and the convex portion 13b are opposed to each other, and a joint gap is formed in a wave shape. The contraction joint 15 has a depth of approximately 50 mm, and a joint material (not shown) is injected into the contraction joint 15 as in the first embodiment. The depth of the contraction joint 15 is not limited to the above value.

Note that the joint structures shown in each of the above embodiments can be applied to both horizontal joints and vertical joints.

As described above, the present invention forms wave-shaped joint gaps and injects the joint material so that the top surface of the joint material approximately matches the surface height of the concrete slab layer at the minimum gap, thereby allowing the joint material to reach the road. There is no bulge, which improves vehicle running performance and prevents damage to the joint material. Even if the joint material caves in as the joint gap expands, the gap between the joints remains corrugated, allowing the vehicle to pass over the joint while keeping its tires in constant contact with the surface of the concrete slab layer. There is no drop in the road surface, which improves the running performance of the vehicle. It also eliminates damage to the concrete slab layer and depression of the roadbed layer, and has the excellent effect of significantly improving durability compared to conventional methods. In this way, good running performance of the vehicle is ensured even if the joint material caves in as described above, so there is no need for any special measures to keep the top surface height of the joint material constant. The structure can be simplified and formed at low cost. In addition, since the concrete slab layer has corrugated joint gaps and the opposing surfaces are approximately vertical,
The load-bearing strength of the joints is high, and since no force other than the vertical load from passing vehicles acts on the roadbed layer, the durability of the roadbed layer can be further improved. Further, the joint material may be set so that its upper surface does not rise above the road surface during the minimum joint clearance, and the amount of the joint material to be injected can be easily adjusted.

[Brief explanation of the drawing]

The drawings illustrate embodiments of the present invention, and FIGS. 1 and 2 are perspective views showing the road joint structures of Embodiment 1 and Embodiment 2, respectively, in cross section in the longitudinal direction of the road. 1, 12... Road, 2... Roadbed layer, 3, 13...
...Concrete slab layer, 3a, 13a...Concavity, 3
b, 13b... Convex portion, 5, 14... Opposing surface, 6,
15... Joint, 7... Injected joint material.

Claims (1)

[Scope of claim for utility model registration] (1) A roadbed layer with earth, sand, fine stones, etc. spread over the roadbed;
In a road in which concrete slab layers with joints provided at predetermined intervals are formed on the subbase layer, the concrete slab layers have joints and opposing surfaces are substantially perpendicular, and the joints have a corrugated shape in the longitudinal direction. A corrugated joint gap is formed by the two opposing surfaces, and a joint material is injected into the joint gap while allowing the top surface to cave in as the joint gap expands, and the top surface of this joint material A road joint structure characterized in that the height is set to approximately match the surface height of a concrete slab layer at the time of minimum clearance. (2) The road joint structure according to claim 1 of the utility model registration claim, wherein the joint is formed over the entire thickness of the concrete slab layer. (3) The joint structure of the road according to claim 1 of the utility model registration, wherein the joint is formed on the upper part of the concrete slab layer.