JPH025843B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to a road widening method.

[Prior art]

The applicant disclosed an invention described in Japanese Patent Application Laid-open No. 71904/1983 as a road widening road using a projecting method. In this invention, an overhanging girder is supported on support piles driven at the end of the widening side of the existing road, and a part of the overhanging girder is placed overhanging the end of the widening side of the existing road. fixed with an anchor for
A floor slab is placed on the overhanging girder via a longitudinal girder in the direction of road travel.

The projecting widening road has the advantage that it does not require the labor of cutting and filling soil during construction, and has the extremely large effect that it has a stable structure due to the support piles and anchors.

[Problems to be solved by this invention]

A problem with the above-mentioned invention is that if the road conditions are inadequate for transporting materials, it is extremely difficult to transport huge objects such as floor slabs to the site.

In order to solve these problems, it is possible to construct formwork on site and widen the road.
In order to assemble the formwork by extending it out from the existing road into the valley, it is an extremely difficult task to erect shoring into the ground on the deep valley side.

Another problem is that when a newly widened road is constructed, it will be higher than the existing road by the overhanging girders, longitudinal girders, and floor slabs, and additional work will be required to adjust the height with the existing road and existing structures. occurs.

[Means for solving problems]

One of the inventions related to this application fixes the mountain side end of the support beam that partially overhangs the existing road with a reaction anchor, supports the valley side with a support pile, and supports the support beam that overhangs the existing road. Formwork is suspended from the beams, reinforcing bars are placed between adjacent support beams, concrete is poured, and a roadbed is constructed. The above problems are solved by hanging the frame and constructing an overhang.

The other invention of this application is to excavate a part of the valley side of an existing road to a predetermined depth along the direction of road travel, and excavate a groove on the mountain side in a direction perpendicular to the direction of road travel, separating the grooves at appropriate intervals. However, the above problem is solved by placing a support beam in the groove and eliminating the difference in height from the existing road.

〔Example〕

The present invention will be described in detail below based on an embodiment shown in the drawings.

(1) Excavation of the existing road In order to eliminate the height difference between the new road and the existing road, the surface of the existing road should be excavated to a specified depth. This invention can be implemented both when an existing road is excavated to a predetermined depth and when it is not excavated.Furthermore, the embodiment shown in the figure is a case where a part of the surface of an existing road is excavated, and the entire surface is excavated and the height difference is Of course, it is possible to make it disappear.

In the figure, a part of the existing road on the valley side is excavated to a predetermined depth along the direction of road travel, and on the mountain side, grooves 1 are excavated in a direction perpendicular to the direction of road travel, separated by appropriate distances in the direction of road travel. Further, an anchor groove 2 continuous with the groove 1 is excavated at the mountain side end of the groove 1.

(2) Support pile driving Support piles 3 will be driven at specified intervals along the widening side edge of the existing road. In the embodiment, each is cast at an extended position of the groove 1. As the support pile 3, a PC pile or the like can be used, and a known driving method can be used by using an earth auger or the like.

A block 4 serving as a pedestal is placed on the support pile 3. Reinforcing bars are made to protrude from the sides of the block 4, so that they can be integrated with concrete when concrete is poured, as will be described later.

(3) Leveling of the existing road Leveling mortar, leveling concrete, etc.5 are placed on the surface of the existing road. It is also possible to level the surface using dry mortar.

(4) Installation of reaction anchors Reaction anchors 6 will be placed at predetermined intervals along the mountain side edge of the existing road. In the embodiment, a hole 7 is formed in the ground from the bottom of the anchor groove 2, a prestressing steel material or a lock bolt 8 is inserted, and a grout 9 is injected to fix it, and the upper end is made to protrude from the hole 7.

A channel steel 10, which is a crossbeam, is positioned in the anchor groove 2 along the groove 2, and the upper end of a prestressing steel member 8 is made to protrude above the bottom surface of the channel steel 10. The upper end of the PC steel material 8 is fixed with a nut or wedge 11. In the case of PC steel, it is tensed after applying a prestressing force.

(5) Installation of support beams The support beams 12 are placed in a direction perpendicular to the direction of road travel, and a portion thereof is overhanging the existing road. A plurality of support beams 12 are placed at appropriate intervals in the direction of road travel. In the embodiment, the support beam 1 is supported by the support pile 3.
2 is supported, and a portion is placed within the groove 1.

As the support beam 12, ready-made members such as I-shaped steel, H-shaped steel, and other concrete beam materials can be used. In the embodiment, H-beam steel is used, and a dowel steel material 13 made of deformed reinforcing bars or the like is protruded from the side surface.

The mountain side end of the support beam 12 is fixed by a reaction anchor 6. In the example, channel steel 1, which is a crossbeam
Fixed via 0. That is, channel steel 1
0 end is located on the flange of the H steel that is the support beam 12, and the mountain side end of the support beam 12 is prevented from lifting up through the channel steel 10 fixed by the reaction anchor 6. ing.

(6) Hanging the formwork The formwork 14 is hung from the part of the support beam 12 that overhangs the existing road. The bottom plate of the formwork 14 is in contact with the lower surface of the support beam 12, and the support beam 12 is in contact with the formwork 14.
The formwork 14 is suspended so that it is positioned within the center.

(7) Arrangement of reinforcing bars, etc. Reinforcing bars 15 are arranged between adjacent support beams 12, 12. When a part of the surface of an existing road is excavated as in the embodiment shown in the figure, the reinforcing bars 15 are placed from the excavated part to the inside of the formwork 14,
If the entire area is excavated or if it is not excavated at all, the entire length of the support beam 12 in the longitudinal direction is covered.

The reinforcing bars 15 are mainly arranged in the direction of road travel, and their ends are fixed to the side surfaces of the support beams 12 by welding.

Other prestressing steel materials may be placed in the formwork 14 and tensioned to provide a prestressing force in the direction of road travel or in the orthogonal direction.

(8) Placing concrete Concrete 16 will be poured to construct the roadbed.

When one surface of the existing road is excavated as in the example shown in the figure, concrete 16 is poured into the excavated portion (including the inside of grooves 1 and 2) and the formwork 14, and the entire surface is excavated, or If no excavation is done at all, concrete 16 is poured over the entire surface of the existing road and within the formwork 14.

After the concrete 16 has hardened, the formwork 14 is removed to complete the roadbed.

(9) Other examples During construction, it may be necessary to close some or all of the existing roads to traffic, but it is desirable to minimize the impact on traffic.

For this purpose, when a part of the existing road is excavated, the excavated part of the groove 1 etc. is filled with sand 17 etc. and compacted to make it passable for a while. All you have to do is discharge it. (Fig. 4, Fig. 5) [Effects of the Invention] One of the inventions according to this application has the above-mentioned configuration, so that the following effects can be obtained.

The overhang method eliminates the need for cutting or filling, greatly reducing the amount of earthwork and shortening the construction period.

There is no need to cut the mountain side, so there is no damage to the existing slope. Therefore, there is no need to carry out new slope protection work.

Since supporting piles are installed at the end of the existing road, a more stable structure can be obtained than one created by filling in the valley side. There is also no need to worry about contaminating rivers, etc.

When a live load acts only on the overhanging portion, the reaction force can be taken by the anchor provided at the mountain end, resulting in a stable structure.

The support beams are embedded in the concrete and function as reinforcing materials, making it possible to construct a strong pull-out and widening road.

The support beams are used not only as reinforcing materials but also to hang the formwork, which simplifies construction.

Since the formwork is suspended from support beams extending from the edge of the existing road, there is no need to assemble support on the valley side ground, making construction extremely easy.

There is no need to transport huge materials such as floor slabs, and because ready-made members such as I steel and H steel are used, it is easy to transport even to sites with poor road conditions.

Other inventions according to this application can obtain the following effects in addition to the above effects.

Since construction can be performed without changing the surface position of the roadbed, there is no need for incidental work for height adjustment with existing roads, existing structures, etc. compared to conventional construction methods.

Since construction can be carried out without completely excavating the entire roadbed, it has wide applicability as a construction method.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an embodiment of the road widening method according to the present invention, FIG. 2 is a longitudinal cross-sectional view in a direction perpendicular to the direction of road travel, and FIG. 3 is a cross-sectional view taken along line A-A in FIG. 4 and 5 are construction sequence sectional views taken along the line BB in FIG. 2, and FIG. 6 is a sectional view taken along the line CC in FIG. 2. 1... Groove, 2... Anchor groove, 3... Support pile, 6... Reaction anchor, 10... Channel steel, 12
... Support beam, 14 ... Formwork, 15 ... Reinforcement bar, 16
……concrete.

Claims (1)

[Scope of Claims] 1. Support piles driven at predetermined intervals on the widening side of the existing road, placed in a direction perpendicular to the direction of road travel, and partially overhanging the edge of the existing road. A beam is supported, the mountain side end of the support beam is fixed to the ground using a reaction anchor, formwork is suspended from the part of the support beam that overhangs the existing road, and reinforcing bars are installed between adjacent support beams. A road widening construction method characterized by placing concrete and constructing a roadbed. 2 Each side edge of the existing road will be excavated to a specified depth along the direction of road travel, and at the mountain side edge, grooves in the direction perpendicular to the direction of road travel will be excavated with appropriate distances separated, and excavated at specified intervals on the widening side of the existing road. A support beam, which is partially placed in the groove and positioned in a direction perpendicular to the direction of road travel, and partially overhangs the existing road, is supported by the support piles driven at a certain angle. The mountain side end of the support beam is fixed to the ground using reaction anchors, formwork is suspended from the part of the support beam that overhangs the existing road, and concrete is placed between adjacent support beams by placing reinforcing bars, etc. A road widening method characterized by pouring concrete and constructing a roadbed. 3. Road widening according to claim 2, characterized in that the trench excavated by the above construction method is once filled with sand, etc. and compacted, and then the sand, etc. is discharged and a support beam is placed in the trench. Construction method.