JP2658692B2 - Earth retaining method for deep excavation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an earth retaining method associated with deep excavation.

[0002]

2. Description of the Related Art In general, earth retaining (mountain retaining) works are carried out for the purpose of preventing collapse of earth and sand on an excavated cut surface when constructing an underground structure or the like. A sheet pile method using a steel sheet pile, a horizontal sheet pile, or the like as a partition for damming is known, and is most commonly practiced.

[0003]

However, this sheet pile method requires a large number of supporting materials because the sheet piles need to be supported by a large number of uprights and supports made of cut beams. There is a problem that a lot of manpower is required for assembling the work, and the work tends to be complicated.

In addition, the length of the parent pile into which the steel sheet pile or the horizontal sheet pile is put is limited, and accordingly, the depth of the retaining wall which can be constructed is naturally limited, and the deep underground structure has a large depth. There was a problem that it was not possible to deal with the construction of objects. Furthermore, since it is only possible to construct vertical earth retaining walls and it is almost impossible to construct inclined earth retaining walls, it cannot be applied to, for example, lining slopes facing roads in mountainous areas, and has very few uses. It was limited.

The present invention has been proposed in order to solve the above-mentioned conventional problems. The present invention enables construction of a deep earth retaining wall, not only construction of a vertical earth retaining wall, but also sloped earth retaining. An object of the present invention is to provide an earth retaining method for deep excavation, which enables wall construction and has many applications.

[0006]

According to the deep earth retaining method according to the present invention, a retaining wall to be constructed is divided into a plurality of elements in a vertical direction, and (A) an inclined narrow vertical hole in the ground. Excavation, formation of a reinforced concrete retaining wall inside the vertical hole with a release material interposed on the inner ground side,
Excavation of ground inside retaining wall, No. 1 by rock bolt
Fixing the upper end of the step (top) element to the ground, stopping the excavation of the ground inside the first element before reaching the lower end of the element, excavating the ground below the element along the inner surface of the element The first-stage element is constructed in the order of forming the second-stage slanted narrow vertical hole, and fixing to the ground with the lock bolt at the lower end of the first-stage element, and preparing the construction of the second-stage element. Step (B): Steps (A) to (C) are performed in the same order to construct a second-stage element, and a step of preparing for construction of a third-stage element is performed. (C) The above-mentioned (B) step is repeated. The step of constructing the lower element, and achieving the object by constructing the lower element sequentially in the depth direction while overlapping the upper and lower ends of the elements of each step to construct the entire retaining wall. is there.

In the step (C), the lower elements are sequentially constructed, and the lowermost elements are constructed. When the exposed height is higher, the uppermost part is formed corresponding to the exposed height of the lowermost element. The lower end portion is fixed to the ground by a lock bolt. When the exposed height is low, only the upper end portion is fixed, and when the exposed portion is hardly exposed, the lock bolt is omitted. In the step (C) for constructing the lowermost element, excavation of a narrow vertical hole which is preparation for constructing the next element is not performed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A deep soil retaining method according to the present invention will be described below with reference to FIGS.

(1) A vertical hole 1 is excavated in the ground into a groove having a constant width (see FIG. 1). The vertical hole 1 varies depending on the shape of the underground structure, but is continuously excavated in the horizontal direction while maintaining a predetermined depth, and is continuously formed into a circular or rectangular ring (FIGS. 11 and 1).
2). Further, the vertical hole 1 is excavated with a slight inclination to the outside so that the elements 14 of each step described later are formed with a slight inclination to the inside (see FIG. 10).

In order to excavate the vertical hole 1, in addition to a chain saw excavator as shown in FIGS. 14 and 15, an excavator such as a disk cutter, a hydraulic shovel, or a clamshell capable of continuously excavating the vertical hole 1 in a groove shape is used. use.

(2) Insert the reinforcing bar 2 into the vertical hole 1 and fix it at the center of the vertical hole 1 (see FIG. 2). As the reinforcing bar 2, for example, a material having high rigidity such as a lattice reinforcing bar or a lath wire mesh, or a material having relatively low rigidity such as a wire mesh is used.

The reinforcing bar 2 having high rigidity, for example,
When using grid reinforcement, the edges of adjacent grid reinforcement are overlapped (see FIGS. 16 and 17), or a male joint 3 made of T-section steel or the like that engages with the edges and a steel pipe For example, by providing a female joint 4 made of such as, the lattice reinforcement is connected to each other by the normal joint method of the reinforcement in the underground continuous wall construction (FIGS. 18 and 19). The spacer 5 is attached so that the cover thickness can be secured (see FIG. 22).

When a reinforcing bar 2 having a relatively small rigidity, for example, a wire mesh is used, H
Pillars 6 made of shaped steel or the like are erected at predetermined intervals, and supported by being tied to the pillars 6 (see FIG. 20).

A release material 7 such as asphalt roofing is inserted into the reinforcement 2 together with the reinforcement (see FIG. 22). The release material 7 is for cutting off the adhesion between the concrete to be cast later and the soil inside thereof, and is for preventing an inward force from being applied to the element 14 when excavating the inner ground.

(3) Concrete 8 is poured into the vertical hole 1 and cured until sufficient strength is developed (see FIG. 2).

When the concrete 8 is poured into the entire vertical hole 1 at a time, the concrete 8 is continuously poured while being careful not to separate it by the concrete pump 9 (see FIG. 23).

When a plurality of parts are divided and driven, the reinforcing bar 2 is fixed to the center of the vertical hole 1 from both sides by a tubular packer 10 and a reaction force receiver 11, and the vertical hole 1 is divided into plural parts. Partition and concrete 8 for each section
(See FIGS. 24, 25 and 26).

The packer 10 and the reaction force receiver 11 are set in advance on the reinforcing bar 2 and are built together with the reinforcing bar 2 in the vertical hole 1. The packer 10 is filled with concrete 8 therein. (Fig. 25, 2
6).

As a method of partitioning the vertical hole 1, there is also a method in which a locking pipe 12 having substantially the same diameter as the horizontal width of the vertical hole 1 is erected at the connecting portion of the reinforcing bar 2 (see FIG. 21).

In this case, in order to fix the reinforcing bar 2 in the vertical hole 1, a connecting bar 13 is protruded from the side of the locking pipe 12, and the end of the reinforcing bar 2 is tied to or over the connecting bar 13. Wrap.

When fiber concrete is used as the concrete 8, the reinforcing bar 2 can be omitted.

(4) When the concrete 8 has developed sufficient strength, the inside of the concrete 8, that is, the concrete wall
Excavation is performed inside 14 (hereinafter simply referred to as “element 14”) (see FIG. 3). For excavation, a conventionally used excavator is used.

(5) After excavation to some extent, the excavation is temporarily stopped, and a plurality of lock bolts 15 are installed in the surrounding ground on the back side from the front side of the element 14 so that the upper end of the element 14 is firmly fixed in the surrounding ground. (See FIG. 4). Excavation of the ground is resumed and stopped when the lower end of the element 14 is still buried in the surrounding ground.

(6) A vertical hole 1 for constructing the second stage element 14 is excavated along the inner surface of the first stage element 14 just constructed. (See FIG. 5). Excavation of vertical hole 1
This is performed in exactly the same way as in the case of (1) (see FIGS. 14 and 15).

(7) A plurality of lock bolts 15 are installed in the surrounding ground on the back side of the element 14 from the front side, and the lower end of the element 14 is firmly fixed in the surrounding ground.

Thus, the construction of the first-stage element 14 and the preparation for the construction of the second-stage element 14 are completed.

(8) The reinforcing bar 2 is erected in the vertical hole 1 in the same manner as in (2), and the release material 7 is inserted inside the reinforcing bar 2.

(9) The vertical hole 1 is filled with concrete 8 in the same manner as in (3), and is sufficiently cured.

(10) The concrete 8, ie, the inside of the element 14, is excavated in the same manner as in (4).

(11) In the same manner as in (5), the element 14
To the surrounding ground.

(12) The vertical hole 1 for constructing the next element 14 is excavated in the same manner as in (6). (13) The lower end of the element 14 is fixed to the surrounding ground in the same manner as in (7).

Thus, the construction of the second stage element 14 and the construction of the third stage element 14 are completed.

Hereinafter, in the same manner, the steps (8) to (13) are repeated to sequentially construct the third and fourth elements 14 in the depth direction to construct the entire retaining wall. (Fig. 6
To FIG. 10). As a result, the upper and lower ends of each of the elements 14, 14,. Be built.

FIG. 13 shows a method for constructing a sloped earth retaining wall, which can be applied to, for example, a slope lining facing a road in a mountainous area. In this case, the slope is not vertical, and the slope changes sequentially. Therefore, it is necessary to construct the entire retaining wall by sequentially changing the slope of the element 14 of each step according to the design.

[0035]

Since the present invention is configured as described above, it has the following effects.

The retaining wall is not constructed over the entire length from the beginning, but is divided into a plurality of elements in the depth direction, and the divided step elements are sequentially constructed in the depth direction to construct the entire retaining wall. Therefore, the vertical hole for constructing each step element may be relatively shallow and need not be deep. Therefore, the excavator can be a small one that is easy to handle, and it is possible to proceed with the work while checking the construction status such as the excavation status of the vertical hole and the concrete pouring condition, thus enabling safe and reliable construction. It is.

By adding the required number of elements in the depth direction, an earth retaining wall of an arbitrary depth can be constructed, and it is possible to sufficiently cope with the construction of a deep underground structure.

By constructing each step element with a slight inclination, the upper and lower elements can be overlapped and connected, and a vertical earth retaining wall integrated as a whole can be constructed. In addition, the mechanical strength is high and the thickness of the retaining wall can be reduced.

Since not only the vertical earth retaining wall but also the inclined earth retaining wall can be constructed (see FIG. 13), for example, the present invention can be applied to slope lining of a road in a mountainous area, and the range of application is extremely wide.

[Brief description of the drawings]

FIG. 1 is a sectional view of the ground showing a method of excavating a vertical hole by a chain saw excavator.

FIG. 2 is a sectional view of the ground showing a method of placing concrete.

FIG. 3 is a sectional view of the ground showing a method of excavating the ground.

FIG. 4 is a cross-sectional view of the ground showing a method of installing a lock bolt.

FIG. 5 is a sectional view of the ground showing a method of excavating a vertical hole.

FIG. 6 is a sectional view of the ground showing an element in the middle of construction.

FIG. 7 is a sectional view of the ground showing an element in the middle of construction.

FIG. 8 is a sectional view of the ground showing a method of installing a lock bolt.

FIG. 9 is a sectional view of the ground showing an element in the middle of construction.

FIG. 10 is a sectional view of the ground showing an element in the middle of construction.

FIG. 11 is a perspective view showing a part of a retaining wall in the middle of construction constructed in a circular shape.

FIG. 12 is a perspective view showing a part of a retaining wall during construction.

FIG. 13 is a sectional view of the ground showing a part of the inclined earth retaining wall during construction.

FIG. 14 is a perspective view showing a method of excavating a vertical hole by a chain saw excavator.

FIG. 15 is a perspective view showing a method of excavating a vertical hole by a chain saw excavator.

FIG. 16 is a front view of a reinforcing bar showing a reinforcing bar arrangement method.

FIG. 17 is a plan view of a reinforcing bar showing a reinforcing bar arrangement method.

FIG. 18 is a front view of a reinforcing bar showing a reinforcing bar arrangement method.

FIG. 19 is a plan view of a reinforcing bar showing a reinforcing bar arrangement method.

FIG. 20 is a partial perspective view of a reinforcing bar showing a reinforcing bar arrangement method.

FIG. 21 is a partial perspective view of a reinforcing bar showing a reinforcing bar arrangement method.

FIG. 22 is a partial perspective view of a retaining wall showing a reinforcing bar arrangement method.

FIG. 23 is a partial perspective view of a retaining wall showing a method of placing concrete by a concrete pump.

FIG. 24 is a partial plan view of a vertical hole showing a method of placing split concrete.

FIG. 25 is a partial plan view of a vertical hole showing a method of placing concrete of a split type.

FIG. 26 is a partial plan view of a vertical hole showing a method for placing split concrete.

[Explanation of symbols]

1 ... vertical hole, 2 ... reinforcement, 3 ... male joint, 4 ... female joint, 5 ...
Spacer, 6 ... prop, 7 ... release material, 8 ... concrete, 9 ... concrete pump, 10 ... packer, 11 ... reaction force receiving, 12 ... locking pipe, 13 ... connecting bar, 14 ... concrete wall (element), 15 ... rock bolts.

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Tadashi Yoshikawa Kashima Construction Co., Ltd. 1-2-7 Moto-Akasaka, Minato-ku, Tokyo (56) References JP-A-4-111808 (JP, A) JP-A Heisei 3-206213 (JP, A)

Claims (1)

(57) [Claims] 1. An earth retaining wall to be constructed is divided into a plurality of elements in a vertical direction, and (A) excavation of an inclined narrow vertical hole in the ground, and a vertical hole in which a release material is interposed on the inner ground side. Formation of reinforced concrete retaining walls inside,
Excavation of ground inside retaining wall, No. 1 by rock bolt
Fixing the upper end of the step (top) element to the ground, stopping the excavation of the ground inside the first element before reaching the lower end of the element, excavating the ground below the element along the inner surface of the element The first-stage element is constructed in the order of forming the second-stage slanted narrow vertical hole, and fixing to the ground with the lock bolt at the lower end of the first-stage element, and preparing the construction of the second-stage element. Step (B): Steps (A) to (C) are performed in the same order to construct a second-stage element, and a step of preparing for construction of a third-stage element is performed. (C) The above-mentioned (B) step is repeated. A step of constructing the lower element, for deep excavation characterized by sequentially constructing the lower element in the depth direction while overlapping the upper and lower ends of the elements of each step and constructing the entire retaining wall. Accompanying earth retaining method.