JPH07247515A - Overhanging structure - Google Patents

Abstract

PURPOSE:To provide an overhang structure which is constituted to effectively transmit a load to the slope side and have an excellent scene and facilitate the construction. CONSTITUTION:L-shaped overhang materials 6 each comprising a support part 7 erected on a foundation on the slope side and an overhanging part 8 are arranged on the soil side. A support member 9 is located between the overhanging part 8 and a slope 3 of each precast overhang 6. An anchor 5 driven on a natural ground on the soil side is anchored to the tip of a roof part 8. The overhanging material 6 is pulled toward the soil side by a prestress force. A tendor 10 extending through the overhang material 6 is also extended through the overhanging material 6 not anchored by an anchor 5 for integral formation. There are neither support column nor wall on the downward slope side, a scene is improved, and a dangerous work on a slope and large scale construction are reduced. The bending bearing of the overhanging material 8 is improved by a prestress force. The prestress force is transmitted to the slope 3 through the overhang part 8 and the support member 9, incurring of a tensile force loss is prevented, and long term stability is improved.

Description

Detailed Description of the Invention

[0001]

[Industrial application] This invention protects road sites and building sites from falling rocks on slopes such as mountainous areas and coastal edges,
Alternatively, it relates to an overhanging structure that can be used as a site such as an overhanging road.

[0002]

2. Description of the Related Art Roads and buildings on slopes such as mountainous areas and coastal edges are exposed to the risk of falling rocks from the slopes. In order to protect against this rockfall, structures such as a cave and a snowshed are used for rockfall protection. In these conventional structures, pillars are erected on both the upslope side and the downslope side of a road site or a building site, and a roof portion is constructed on the pillars to cover the site. In other words, these structures covered the site like a tunnel to prevent earth and sand and rocks from falling onto the site.

Similarly, it is extremely difficult to secure a site for roads and buildings in mountainous areas and coastal margins. For this reason, constructions such as cutting mountains and building columns on the sea to build a floor on the site were made.

[0004]

However, the conventional structure for protecting against falling rocks described above does not provide a good view because the structure covers the site. In other words, even when viewed from the outside, the harmony with the surrounding landscape is not good, and when viewing the outside from the site side, it obstructs the view. Also, with a structure like a snow shed, pillars are erected on the down slope side of the site, but the ground on the down slope side is easily collapsed and unstable, and it is extremely difficult to erect pillars on it. Therefore, since it is necessary to reinforce the ground on the down slope side and to set up a pillar on this, the work becomes extremely large-scale work, and the work on the slope involves a lot of labor and danger.

This is the same as the construction for securing the above-mentioned site, the work of cutting down the mountain is extremely large-scale work, and the construction of erecting the pillar on the sea or slope imposes a great risk to the worker. is there.

The present invention has been made in order to solve the above problems, and it is well harmonious with the surrounding scenery, and does not block the outside scenery, and can be easily constructed. The purpose is to provide a structure.

[0007]

The overhanging structure according to the present invention is designed to support the load and its own weight only on the slope side. In the present invention, an overhanging material made of precast concrete is used, and the precast overhanging material is L-shaped from a support portion standing up on a foundation on the slope side and an overhanging portion covering a road site or a building site. A precast overhang is placed on the foundation constructed on the slope, and multiple pieces are lined up continuously. A support member is interposed between the overhang portion and the slope of each precast overhang member. The support member is for preventing the precast protective body from falling to the mountain side, and may be a precast concrete member or a steel member,
Various shapes and materials can be adopted. Anchor is placed in advance on the slope, and prestressing force is applied to this to fix it at the tip of the precast overhang and pull it toward the mountain side. In order to arrange this anchor in the overhanging portion of the precast overhanging material, it is preferable that the overhanging portion is formed in a groove shape having a U-shaped cross section.

The precast overhanging material is not entirely fixed by the anchor, but some desired ones are selected and fixed by the anchor. For example, among the multiple precast overhanging materials arranged side by side, anchors fix the two precast overhanging materials, and the skipped precast overhanging material penetrates the tension material that penetrates the precast overhanging material fixed by the anchors. And fix it, and integrate the precast overhanging material. A cement-based hardening material such as mortar or concrete is filled inside the groove of the precast overhanging material.

The structure constructed as described above is used as a rockfall protective body or as an overhanging site. When it is used as a rockfall protection body, it is constructed so as to extend over the road site or building site, and earth and sand for buffering is placed between the support part and the slope and on the overhang part. A projecting structure covers the site and protects against falling rocks. When it is used as an overhang site, a foundation is constructed in the middle of the slope and a precast overhang material is erected on this to construct the structure. Sediment is filled between the support and slope of this precast overhanging material, and the overhanging area is used as a road site or building site.

[0010]

[Operation] Since the entire structure is supported only on the mountain side, no foundation work is required on the unstable down slope side. Since the anchor is anchored at the tip of the protective body, the anchor can exert a prestressing compressive force on the roof portion of the precast protective body to improve bending strength. The tension of the anchor is transmitted from the precast overhanging material to the mountain side through the support member. This makes it possible to maintain tension over the long term.
By forming the overhanging portion of the overhanging material in a groove shape, it becomes possible to dispose the anchor in the roof portion and to fill the cement-based hardening material as a formwork.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on an embodiment shown in the drawings. The embodiment shown in FIG. 1 is a case in which the road 1 is constructed as a protective body against rockfall. Under the slope on the mountain side of the road 1, a concrete foundation 2 is constructed along the road 1. On the slope 3, a concrete foundation 4 is constructed along the road 1. A ground anchor 5 is placed in the ground through the foundation 4. Ground anchor 5
Is a device in which a plurality of tension members are arranged in a sheath, inserted into a drilled hole, and grout is injected and fixed. It is also possible to first place the ground anchor 5 and then construct the foundation 4.

A precast overhanging material 6 is placed on the foundation 2. The precast overhanging material 6 includes a supporting portion 7 and an overhanging portion 8.
To L-shape, the supporting portion 7 is erected on the foundation 2, and the projecting portion 8 is projecting to the site side. The precast overhanging member 6 is formed in a groove shape with a U-shaped cross section, which extends from the overhanging portion 8 to the supporting portion 7. A supporting member 9 is interposed between the overhanging portion 8 of the precast overhanging member 6 and the foundation 4 of the slope 3. The support member 9 is made of precast concrete, and has a cylindrical shape in the embodiment. The ground anchor 5 is passed through the support member 9 and the overhanging portion 8,
A prestressing force is applied to fix the tip of the overhanging portion 8. This prestressing force pulls the precast overhanging material 6 to the mountain side. The prestressing force is transmitted to the sloped foundation 4 through the roof portion 8 and the support member 9 of the protective body 6.

The anchor 5 is fixed by the desired precast overhanging member 6 among the precast overhanging members 6 arranged side by side.
In the embodiment, every other precast overhanging material is fixed by the anchor 5, and the unbonded PC strand, which is the tension material 10 penetrating this, is also passed through the precast overhanging material 6 not fixed by the anchor 5. Prestressing is applied to fix the ends to the side surfaces of the overhanging material 6, and all the precast overhanging materials 6 are integrated. In some cases, the tension members 10 may be integrated by fixing some of the entire overhang members 6 and then, the tension members 10 may be integrated so that they are sequentially overlapped and connected.

Mortar and concrete are placed in the grooves of the overhanging portion 8 and the supporting portion 7. Reinforcing bars are arranged in the groove if necessary. Such precast overhanging members 6 are continuously arranged along the road 1. Sediment 11 is packed between the support portion 7 and the slope 3 of the precast overhanging material 6, and the overhanging portion 8 is also overlaid with earth / sand 11 for buffering the impact of falling rocks.

FIG. 4 shows the case where the projecting structure is used as a road site. The foundation 2 is constructed in the middle of the slope 3, and the precast overhanging members 6 are arranged and integrated as described above. Sediment 11 is packed between the support portion 7 and the slope, and the road and the overhanging portion 8 are paved to form a road.

[0016]

EFFECTS OF THE INVENTION The present invention has the above-mentioned constitution and can obtain the following effects. The prestressing force of the anchor is transmitted to the rock mass on the slope through the supporting member of the overhanging member, and the tensile force of the anchor is obtained. Can be expected to be maintained, it will be retained for a long time without loss, and the stability of the structure is guaranteed. Since the anchor is fixed to the tip of the overhanging portion of the protective body, the bending resistance of the overhanging portion can be improved by the prestressing force, and at the same time, the horizontal load from the ground side can be shared by the anchor. By forming the overhanging portion of the overhanging member in a groove shape, the anchor can be embedded and the overhanging member can accurately receive this force. The use of precast overhanging materials reduces on-site work and shortens the construction period. Since the overhanging material is supported only on the slope side of the site, work on the slope side and large-scale temporary construction are reduced, which facilitates construction and reduces the risk. When used as a rockfall protector, there are no pillars or walls on the down slope side, and the view seen from the outside is good, and the view is not obstructed by roads, etc., and good visibility can be obtained. Since the overhanging material has a groove shape with a U-shaped cross section, the weight of the member can be reduced, and the carrying-in work is facilitated.
Since this groove can also be used as a formwork, the formwork is labor-saving, economical and the construction period can be shortened.

[Brief description of drawings]

FIG. 1 is a perspective view of an overhanging structure for rockfall protection.

FIG. 2 is a cross-sectional view of an overhanging structure for rockfall protection.

FIG. 3 is a cross-sectional view of an overhang portion of a precast overhang member.

FIG. 4 is a cross-sectional view of an overhang structure for an overhang road site.

[Explanation of symbols]

 1 Road 2 Foundation 3 Slope 4 Foundation 5 Ground anchor 6 Precast overhanging material 7 Supporting portion 8 Overhanging portion 9 Supporting member 10 Tensile material 11 Sand

Claims (3)

[Claims] 1. A plurality of L-shaped precast overhanging members, each of which is composed of a support portion standing on a foundation on the upslope side and an overhanging portion covering the site, are arranged on the upslope side to form an overhanging portion of the precast overhanging material. An anchor placed on the ground on the upslope side is fixed to the tip of the overhanging part with a support member interposed between the upslope and the upslope, and the desired precast overhanging material is pulled toward the upslope side by prestressing force. An overhang structure that acts as a rockfall protective body that covers the site by allowing the tension material that penetrates the fixed precast overhanging material to penetrate through the precast overhanging material that does not have the anchor and fix it to integrate the precast overhanging material. 2. A support portion standing upright on a slope-side foundation,
Anchor placed in the ground on the slope side, with precast overhanging materials arranged in a plurality of L-shapes with overhanging parts extending from the slope, arranging the precast overhanging materials on the slope side, interposing a supporting member between the overhanging part and the slope The precast overhanging material is fixed to the tip of the overhanging portion, and the desired precast overhanging material is pulled to the slope side by the prestressing force. An overhang structure where the precast overhanging material is integrated by penetrating it and fixing it, and the overhanging part is the site. 3. The overhang according to claim 1, wherein the overhang portion of the precast overhang material is formed in a groove shape having a U-shaped cross section, and the precast overhang material is filled with a cement-based hardening material. Structure.