JPH0613770B2 - Method of constructing mountain retaining wall with parent pile - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method of manufacturing a retaining wall having a main pile to prevent surrounding sediment from collapsing when excavating downward from the ground.

[Background technology]

Conventionally, parent piles (3) 'made of H steel have been installed at appropriate intervals to the required depth to prevent the soil from collapsing when excavating downward from the ground (1). It is known that wooden or concrete horizontal sheet piles are sequentially stacked up to the depth of the excavated bottom between 3) '. However, in this conventional example, as the excavation proceeds, the horizontal sheet pile (6) is fitted between the main pile (3) 'and the main pile, at which time the horizontal sheet pile (6) is inserted. It disturbs the soil on the back side of the ground and causes ground subsidence in the surrounding area. Moreover, since the work of inserting the horizontal sheet pile (6) is required at the same time as the excavation proceeds, there is a problem that the work becomes complicated. Also, in the past, the water on the back surface of the mountain stop leaks from the joint between the horizontal sheet pile (6) and the horizontal sheet pile (6), causing the sediment to flow to the excavation surface together with the leakage, causing the subsidence of the ground behind the mountain stop. There was a problem of tightening.

[Object of the Invention]

The object of the present invention is to prevent the ground subsidence on the back side without damaging the surrounding ground because the underground wall can be constructed and the main piles can be built before excavation is started and the water blocking effect is excellent. In addition, the present invention provides a method of constructing a mountain retaining wall having a main pile that can surely prevent the collapse of earth and sand.

[Disclosure of Invention]

The method for creating a mountain retaining wall having a parent pile of the present invention is the ground (1)
When constructing a retaining wall to prevent the surrounding sediment from collapsing when excavating downward from the ground, the soil cement wall underground wall (2) up to the almost planned excavation bottom The lower end of the part is formed to have almost the same depth,
The ground is deeper than the underground wall (2) with arbitrary spacing in (2).
A parent pile (3) such as H steel is built up to the support layer of (1), and the object of the present invention described above is achieved by adopting such a method.

Hereinafter, the present invention will be described in detail with reference to Examples. In the present invention, first, the underground wall (2) of soil cement wall is formed up to almost the planned excavation bottom surface. Here, in forming the underground wall (2) of the soil cement wall, for example, a circular hole is drilled with an excavator and the excavated soil and a solid material such as cement milk are formed in the circular hole. Mixed and stirred soil cement columns (4)
The soil cement columns (4) are formed by partially lapping them one after another to form a column wall, which can be used as the underground wall (2), or multiple excavation shafts can be used. With a multi-axis excavator having a plurality of circular holes, a rectangular cemented hole is formed in the shape of a continuous bridge, and the soil cement wall is formed by mixing drilled earth and sand and a cementitious material such as cement milk in the rectangular hole. (5) is formed and a continuous wall is formed by forming the soil cement wall (5) one after another so that the ends partially overlap each other, and this continuous wall is used as the underground wall (2). It is a thing. Here, the depth of the lower end of each part of the underground wall (2) is almost equal as shown in FIG. After forming the underground wall (2) as described above, a main pile (3) such as H steel is built in the underground wall (2) at arbitrary intervals.
Here, the main pile (3) is built deeper than the underground wall (2) so that its lower portion is located below the lower end of the underground wall (2) by a required length. After constructing the retaining wall with parent piles as described above, the ground (1) surrounded by the retaining wall is excavated downward.In this case, the underground wall (2) is excavated. Sometimes it serves to prevent water from leaking from the surrounding ground, so the depth of the underground wall (2) is the minimum required to stop the water (that is, the planned depth). The excavation bottom) is sufficient, while the main pile (3) is planned to prevent the soil from collapsing due to the earth pressure or water pressure on the back side even when the excavation bottom is excavated. It is necessary to build it deeper than the excavated bottom surface by the required length.

〔The invention's effect〕

In the present invention, the underground wall of the soil cement wall is formed to almost the same depth as the lower end portion of each part of the underground wall to the excavated bottom surface almost as described above, and Since the main pile is built deeper than the underground wall to the support layer of the ground (1) at arbitrary intervals, the underground wall and the main pile can be constructed before excavation starts, and a horizontal sheet pile is constructed during excavation. Not only does it require complicated work when it is installed, but since it does not take a while to install the horizontal sheet pile during excavation as in the past, the construction of the horizontal sheet pile disturbs the soil on the back, The surrounding ground subsidence does not occur. Moreover, since the underground wall of the soil cement wall is formed up to almost the planned excavation bottom surface, water can be reliably stopped by the underground wall of the soil cement wall and it is possible to prevent the subsidence of the ground on the back side of the earth retaining wall. Yes, and because the main pile is built in the underground wall deeper than the underground wall, the main pile is still deeper than that even if it is excavated to the specified ground. The bottom wall of each part has the same depth at the lower end, and only the main piles such as H steel are built deeper than the bottom wall. Therefore, without providing something like a soil cement column in the part that does not require water stoppage (that is, the part below the underground wall), the water stoppage is secured by the underground wall to prevent collapse of the underground wall. Secure with parent piles such as H steel, there is no wasteful configuration and cost can be reduced. Also, when building a main pile such as H steel, by inserting the underground wall before the soil cement hardens, it is possible to insert it to the lower end of the underground wall with almost no impact force, and then Since only the portion below the underground wall is driven in, the driving can be done easily.

[Brief description of drawings]

FIG. 1 is a perspective view of a conventional example, FIG. 2 is a perspective view of the present invention, FIG. 3 is a sectional view of an example of an underground wall formed by the present invention, and FIG. 4 is another underground wall of the same. (1) is the ground, (2)
Is the underground wall and (3) is the main pile.

Claims (1)

[Claims] 1. When constructing a retaining wall to prevent the surrounding soil from collapsing when excavating downward from the ground,
The soil cement wall underground wall is formed to almost the expected bottom of the excavation, and the depths of the lower end portions of each portion of the underground wall are formed to be approximately equal to each other. A method of constructing a retaining wall having a parent pile, characterized in that a parent pile such as an H steel material is built deeply into the support layer of the ground.