JPH0336318A - Method of construction for stopping natural ground - Google Patents

Abstract

PURPOSE:To contrive safe and inexpensive execution by digging the natural ground divided into a plurality of steps, fixedly driving an anchor to raise a retaining structure, fixing it to the anchor and piling the structure. CONSTITUTION:The natural ground is excavated to be divided into a plurality of steps by each predetermined height from the upper. In each of this excavation, an anchor 2 is driven toward the natural ground from an excavated natural ground surface 1. Here, a nut 3 and a steel plate 4, which serve as a structure stopper tool, are left as inserted to a protruding part from the natural ground of the anchor 2. Next, an existing retaining panel 5, which serves as a retaining structure, is raised along the excavated natural ground surface 1 and fixed by a nut 6 or the like. Water from the natural ground is drained by packing broken stones 9 between the retaining panel 5 and the excavated natural ground surface. Further, by repeating similar work, the total surface of the excavated natural ground 1 is coated with the retaining panel 5.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a retaining method for stabilizing the surface of an excavated ground, and in particular, a retaining method for stabilizing a long excavated ground. It is related to.

[Prior art and its issues]

When retaining a long and high ground, one possible method is to excavate from the top to the bottom all at once, and then install retaining structures along the surface of the excavated ground.

However, after excavating a large excavation surface, the excavated ground remains unstable until the earth retaining structure is fixed, and it is extremely dangerous to work under this ground surface.

For this reason, it may be possible to excavate in stages from the top to the bottom, drive anchors after each excavation, and install earth retaining structures such as earth retaining panels to hold the mountain in place.

However, after installing the earth retaining structure above, excavating beneath it was an extremely difficult task.

Therefore, in retaining earthworks, there is still no established method of excavating from above, stabilizing the earth, excavating downwards, and then placing earth retaining structures along the excavated earth.

This invention was made in order to solve the above-mentioned problems, and an object of the present invention is to provide a mountain retaining method that allows safe construction and can be constructed at low cost.

[Means to solve the problem]

The mountain retaining method according to the present invention temporarily secures the 11M order while excavating the ground.

When retaining a long excavated surface, the excavation is done in multiple stages from the top to the bottom. In other words, the tunnel is excavated one after another to a predetermined height, and temporary fixing is performed after each excavation.

Anchors are driven and fixed from this ground excavation surface. An anchor with relatively high rigidity is used; for example, a rod-shaped deformed steel rod can be driven into the ground and fixed with grout. In addition, a large diameter steel stranded wire has enough rigidity to hold an earth retaining structure, which will be described later. The anchors are set at relatively close intervals,
The spacing is every 1-2 m. These anchors strengthen the ground and reduce the possibility of collapse. In other words, anchors extend into the ground like the roots of plants growing in the ground and prevent the ground from collapsing.

While temporarily secured with this anchor, excavate downward one by one.
Excavate a long ground surface by repeating temporary fixing.

After excavation is complete, earth retaining structures such as existing concrete panels will be erected along the excavation surface. A structure stopper such as a nut or plate is attached to the protruding part of the anchor from the ground, and the earth retaining structure is held by inserting the protruding part of the anchor. Fix the earth retaining structure to the anchor using nuts, etc. Various earth retaining structures can be used, such as flat earth retaining panels and other earth retaining blocks. A gap may be provided between the earth retaining structure and the ground and filled with earth and sand or crushed stone.

〔Example〕

Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings.

First, the ground is excavated from above along a planned line in multiple stages at predetermined heights. For each excavation, an anchor 2 is driven from the excavated ground surface 1 toward the ground. Although various configurations can be adopted for the anchor 2, in the example, a deformed steel rod having a screw on the outer periphery was used, and was fixed with grout material injected into the hole. Anchors 2 are multiple anchors placed at relatively short intervals, and these anchors 2 reinforce the ground, eliminating the possibility of major collapse.
It will be in a temporary state.

Leave the part of anchor 2 that protrudes from the ground sufficiently long.

(Fig. 1) A nut 3 and a steel plate 4, which are structural fasteners, are inserted into the part of the anchor 2 that protrudes from the ground. Since the anchor 2 uses a fully threaded deformed steel rod, the position can be finely adjusted by rotating the nut 3. If the nut 3 alone can support the structure, the plate 4 is not necessary.

In this way, the upper excavated ground surface is temporarily fixed with the anchors 2 to prevent collapse, and the lower part is excavated further.

(Fig. 3) This excavated ground is also temporarily secured with anchors 2 in the same manner as described above. (Figure 4) After that, excavation and temporary fixing are repeated to excavate the entire surface of the ground as planned. (Figures 5 and 6) Ready-made earth retaining panels 5, which are earth retaining structures, are erected along the excavated earth surface l. The above-mentioned anchor 2 is passed through the earth retaining panel 5 through the protruding portion of the ground, held at a predetermined distance from the ground by a structural fastener, and fixed with a nut 6 or the like.

As the retaining panel 5, in the embodiment, an arcuate arch portion 7 is used.
A retaining panel 5 having a shelf-like reinforcing section 8 on the front surface thereof is used. The anchors 2 are passed through both ends of the retaining panel 5 and fixed.

Crushed stones 9 are packed between the earth retaining panel 5 and the excavated ground surface 1 for draining water from the ground. (Fig. 7) When filling with earth and sand, it is sufficient to bury a drainage vibrator etc. in the ground.

The earth retaining panels 5 are sequentially stacked on top of the earth retaining panels 5, fixed to the anchors 2, and crushed stone 9 is filled.

(Fig. 8) The above operations are repeated until the entire surface of the excavated ground l is covered with the retaining panel 5.

The earth retaining structure is not limited to the earth retaining panel 5 having the shape described above, but various types such as flat panels can be used.

〔Effect of the invention〕

With the above configuration, the present invention can obtain the following effects.

■ The ground can be excavated in multiple stages from above to below, and the surface of the excavated ground can be temporarily secured with anchors at each stage, reducing the risk of the ground collapsing during construction. Able to work safely.

@ Since temporary fixing is performed using only anchors, the construction cost remains the same compared to conventional mountain fixing, making it possible to perform construction at a lower cost.

O Due to the above-mentioned effects, it becomes possible to secure vertical ground, which has been extremely difficult in the past, extremely safely and easily.

0 This construction method is used to retain a long ground that has not been previously established, and is similar to the reverse construction method in which earth retaining structures are excavated from the top, stabilized, and then excavated to the bottom, and then piled up earth retaining structures from the bottom. Construction is now possible.

[Brief explanation of drawings]

1 to 8 are sectional views in the construction sequence of an embodiment of the present invention, FIG. 9 is a cross sectional view when the heaping is completed, and FIG. 10 is a perspective view of the construction state. ■... Excavation ground surface, 2... Anchor 3... Nut, 4... Steel plate, 5... Earth retaining panel, 6
... Nut, 7... Arch part, 8... Reinforcement part, 9
...Crushed stone.

Claims (3)

[Claims] (1) Excavate the ground in multiple stages from above to below, drive and secure multiple anchors from the ground excavation surface at each stage, and after excavating to the bottom end, earth retaining is carried out sequentially from below. A mountain retaining method in which a structure is erected along the excavated surface and fixed to the anchor, and earth retaining structures are piled up along the excavated surface. (2) The mountain retaining method according to claim (1), characterized in that the anchor is a ground reinforcement anchor in which a highly rigid rod-shaped body is fixed in the borehole with grout material. (3) The mountain retaining method according to claim 1, wherein a structure stopper is attached to a portion of the anchor protruding from the ground to hold the earth retaining structure.