JPH07150565A - Earth retaining construction method - Google Patents

Abstract

PURPOSE:To form a projecting part which is high in rigidity strength in the earth retaining part and which is necessary for vegetation or the like. CONSTITUTION:A pile hole 1 arranged in a zigzag shape in a plan is excavated downward from an upper part of bedrock G. A steel pile 2 is located in the pile hole 1, and the steel pile 2 is consolidated, and while driving a bedrock anchor 8 or the like according to its necessity, the bedrock is excavated in stages. An exposure part of the steel pile 2 in respective excavating stages is connected so that the plan shape becomes an almost triangular shape whose bedrock side is set as a top part, and a horizontal floor board 5 or the like is formed in this part, and a wall surface 6 or the like is formed on two surfaces coming into contact with the bedrock in an almost triangle pole-shaped space created by excavation proceeding to a lower part of the bedrock.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mountain retaining method for excavating rocks by forming piles and using the piles as pillars to form a wall surface for preventing the collapse of the rocks to reach the bottom of the rocks.

[0002]

2. Description of the Related Art Conventionally, in the case of construction such as constructing a road or a residential land above a high ground and excavating the ground to form a steep slope, a pile of steel pipe or the like is laid over the ground. This pile is used as a pillar and a bellows is installed while constructing ground anchors such as earth and sand anchors and rock anchors, etc. The method of excavation to reach the hillside was common.

[0003]

However, in the above-mentioned conventional pillar pile type mountain retaining method, since the pillar piles are arranged so as to have a linear shape in a plan view, the mountain retaining portion in contact with the natural ground is almost flat. The rigidity is not so high. Therefore,
When constructing in a place where the height difference is extremely large and earth pressure is strong, it is necessary to make the cross-sectional size of the pile that will be the pillar large, and also to make the pitch of the pile very dense, ground anchor, etc. It is necessary to use the auxiliary construction method of
The construction was large-scale and required carefulness. Therefore, if construction can be simplified while ensuring sufficient safety, the construction period and construction cost will be greatly reduced. In addition, when performing a steep slope using the above-mentioned conventional mountain retaining method, due to the construction method, only unevenness of a slope frame can be formed on the slope surface, and large-scale vegetation treatment is required. If necessary, the steel piles and mountain retaining members must be specially processed in advance, and the protruding portions such as shelves that are unnecessary for the original strength of the mountain retaining work must be separately formed to hold the earth and sand. It was uneconomical both in terms of strength and strength. The present invention has been made to solve the above problems, and an object of the present invention is to provide a mountain retaining method in which the mountain retaining portion has high rigidity and can form a protruding portion necessary for processing vegetation or the like. .

[0004]

In order to solve the above-mentioned problems, the pile retaining method according to the present invention is to build a pile from the upper part of the natural ground and form a wall surface for preventing the collapse of the ground by using the pile as a pillar. A pile retaining method for rock excavation to reach the bottom of the rock. A pile hole excavation process in which pile holes arranged in a staggered plane are drilled downward from the top of the rock. Pile installation process for building piles, then pile consolidation process for consolidation of the built-in steel piles, and then ground anchors are used in combination with ground anchors if necessary, and each ground excavation stage is performed. The exposed parts of the steel pile are connected so that the planar shape thereof is a substantially triangular shape with the natural ground side as the apex, and a floor slab is formed in the substantially triangular portion, and a substantially triangular shape is formed by excavation downward toward the natural ground. Wall surfaces on two faces that contact the ground of the columnar space Configured with a, a natural ground excavating forming.

[0005]

According to the present invention having the above-mentioned structure, when a plurality of piles are built from the upper part of the natural ground, the piles are arranged in a staggered plane, and when the ground excavation is carried out stepwise, at each excavation stage. The exposed steel piles are connected in such a way that their planar shape is a substantially triangular shape (a type of truss structure) with the top of the natural ground side as a top, and the ground is a substantially triangular column-shaped space formed by excavation downwards. Since the wall surface is formed on the two surfaces in contact with the pile, the rigidity of the pile itself and the mountain retaining member is higher than that of the conventional method in which the piles are simply arranged in a line. Further, the present invention, from its construction method, and in order to increase its strength, inevitably forms a floor slab in the substantially triangular portion connecting the exposed portions of the steel piles, and this floor slab portion is substantially Since a triangular shelf is formed, vegetation can be easily processed by using this.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, in this mountain retaining method, first, a pile hole excavating step of excavating a pile hole 1 by a pile hole excavator 31 is performed from the upper part of a mountain of a natural ground G to be excavated downward. (FIG. 1 (A)). The excavation angle of the pile hole 1 is determined by the slope of the slope wall surface to be formed, but if the ground is good, it may be vertical. 2 to 5, an example in which the pile angle is vertical is shown.

In this case, the plane arrangement of the pile holes is so-called "staggered" as shown in FIG. 2 or FIG. The diameter of the pile hole 1 should just be a diameter slightly larger than the bracket diameter of the steel pile 2 described later, as long as the steel pile 2 described later can be easily inserted. There is no need to drive the piles into "friction piles" because they will be consolidated after the piles have been built. As the pile hole excavator 31, an earth auger machine when the ground is earth and sand, a percussion type excavator when the ground is rock, a full-circle rotary all-casing excavator, a rock drill machine, and the like are used.

After the excavation of the pile hole 1 is completed, next, the pile hole 1
The steel pile 2 is inserted by the pile builder 32 to build up the pile until the tip of the pile reaches the bottom of the pile (FIG. 1 (B) or FIG. 2). In this embodiment, the pile hole 1 has a circular cross section and the steel pile 2 is a hollow circular steel pipe pile.

The steel pile 2 may be one having a cross-sectional shape other than the hollow circular steel pipe, such as a hollow square steel pipe or a large H-shaped steel. Also, the pile is a jointless one
It may be a real long pile, or may be of a type that is extended in the pile hole 1 while being joined by a high-strength bolt joint or the like on site. As shown in FIG. 2 or FIG. 6, a plurality of brackets 21 for interconnection are formed on the steel pile 2 in advance by factory welding or the like. The bracket 21 serves not only as a metal fitting for connecting the piles, but also as a spacer for securing a substantially constant space with the hole wall when the pile is inserted into the pile hole 1. In the present embodiment, an example in which four brackets 21 are provided on the circumference of the steel pile 2 has been described, but this number may be any number. Also,
The bracket 21 does not need to be continuous in the longitudinal direction of the steel pile 2 and may be provided only at the connecting portion described later. In addition, bolt holes for connecting piles, which will be described later, are opened in the bracket 21. Further, when the steel pile 2 is built, as shown in FIG. 3 or FIG. 6, the steel pile 2 is built so that the corresponding brackets 21 of the piles face each other.

In order to build the piles, it is usually enough to simply drop the piles. Therefore, as the pile building machine 32, a normal crane machine or the like is used. If the height difference at the construction site is very high and the pile hole 1 bends in the middle, or the ground collapses strongly and the wall of the hole of the pile hole 1 often falls, the steel piles along the pile hole 1 Since it may be necessary to insert 2 forcibly, a vibro hammer machine or a press-fitting machine may be used.

When the steel pile 2 is inserted to the bottom of the pile hole 1,
Next, from the bottom of the pile hole 1 or the tip of the steel pile 2 upwards, cement milk, mortar, concrete, or the like is injected into the periphery of the steel pile 2 or the inside of the steel pipe by the injection machine 33 to solidify the pile. The pile root consolidation process is performed (FIG. 1 (C) or FIG. 3).

[0012] In order to inject concrete or the like, normally, it is sufficient to pour the concrete or the like into the pile hole 1 or the hollow portion of the steel pipe simply by gravity dropping.
A normal concrete pump machine is used. If the height of the construction site is very high and the pile hole 1 bends in the middle, or the ground collapses strongly and the hole wall of the pile hole 1 often falls off, concrete etc. Since there may be a case where it is necessary to forcibly press in, a dedicated press-fitting machine or the like may be used.

In the present embodiment, an example in which concrete or the like is poured from the lower end of the steel pile 2 to the vicinity of the ground surface of the upper ground G to completely solidify the steel pile 2, has been described. This is to inject concrete or the like only into a necessary portion near the lower tip portion of the steel pile 2 and to perform root consolidation only near the lower tip portion of the steel pile 2, and the pile hole 1 and the steel pile 2 above the root consolidation portion.
The portion between and may be hollow. With this construction, the concrete does not have to be worn.
It is also possible to use the steel pile 2 as it is, or after painting it, as a temporary or permanent structure mountain retaining work.

After the completion of the consolidation of the steel piles 2, the ground excavation process is started. In the ground excavation step, first, the upper part of the ground G is slightly (about several tens of cm) dug down and the steel pile 2 is dug out. Next, concrete or the like around the bracket 21 is peeled off and removed to expose the bracket portion. Then, as shown in FIG. 3 or FIG. 6, the connecting member 4 is provided between the steel piles 2 arranged in a staggered manner so that the planar shape thereof is a substantially triangular shape with the apex located on the natural ground G side.
I, and firmly connect it via the bracket 21 with a high-strength bolt or the like. This is the first-stage steel pile connection work (FIG. 1 (D) or FIG. 3). As the connecting member 4, mountain steel, small H-shaped steel, or the like is used. According to this structure, the tops of the steel piles 2 are connected by a kind of truss structure, and the rigidity strength is increased as compared with the case of a pillar pile having a normal linear arrangement.

When the first-stage steel pile connecting work is completed, next, the first-stage horizontal slab work is started. In the first-stage horizontal slab work, the distribution reinforcing bars 28 and the like are arranged in the substantially triangular portion formed by the connecting members 4 that are passed between the steel piles 2 arranged in a staggered manner, and the concrete is cast on site. Then, the horizontal floor slab 5 having a substantially triangular shape is formed (FIG. 1 (D) or FIG. 4). With this configuration, the top rigidity of the steel pile 2 is further enhanced.

The horizontal floor slab 5 is formed of cast-in-place concrete, and the precast concrete panel manufactured in the factory is firmly connected with the bracket 21 using high-strength bolts, etc. It may be formed by filling mortar or the like in the space between the first and second portions.

When forming the horizontal floor slab 5, the connecting members (4c in FIG. 3) other than the two connecting members (4a, 4b in FIG. 3) on the side in contact with the natural ground among the connecting members 4 are used. Then, a distribution reinforcing bar or the like is arranged on the connecting member 4c, and the first-stage horizontal beam 12, which is a steel-framed reinforced concrete beam, is constructed by winding cast-in-place concrete in a substantially rectangular cross-sectional shape. With this structure, the strength is increased and the aesthetic appearance is improved (FIG. 4). In the above, the connecting member 4c
The cross-section of the steel-framed reinforced concrete beam formed by rolling in with cast-in-place concrete is not limited to a rectangular cross-section, and may have another cross-sectional shape such as a circle or an ellipse. Alternatively, the connecting member 4c may be used as a beam as it is without being wound with cast-in-place concrete.

In the above case, as shown in FIG. 3 or 6, so that the top of the triangle is located on the ground G side,
In addition to connecting the staggered steel piles 2 to each other, the triangular peaks on the natural ground G side may be connected to each other. By doing so, the tops of the steel piles 2 are connected by the complete Warren truss structure, and the rigidity strength is further increased as compared with the case of the above connection. Further, if a horizontal floor slab is also formed in this portion with concrete or the like and the entire frame of the warren truss structure is used as the floor slab, the rigidity strength of the top of the steel pile 2 is dramatically increased.

When the above-mentioned first-stage horizontal floor slab work is completed, next, the first-stage mountain retaining wall work is started. In the first-stage earth retaining wall work, a ground excavator 34 such as a bulldozer excavates the ground up to the first-stage excavation surface 11 below the natural ground G, and between the steel piles 2 arranged in a staggered manner by the excavation. The first retaining wall surface 6 is formed on the two surfaces of the substantially triangular column-shaped space that are in contact with the natural ground G (FIG. 1 (E) or FIG. 4). This mountain wall 6
In addition to supporting the earth pressure of the natural ground G itself, it also plays a role of preventing the cut surface of the excavated natural ground G from falling off the skin.

In this first-stage earth retaining wall construction, the distribution rebar 29 or the like is arranged on the part of the vertical surface (or slope) formed by the staggered steel piles 2 that is in contact with the natural ground G. Then, concrete is cast on site to form the wall surface 6 having a substantially rectangular shape (FIG. 1 (E) or FIG. 4).

The wall wall 6 is formed of cast-in-place concrete, and the precast concrete panel manufactured in the factory is firmly connected to the ground pile by using the bracket 21 of the steel pile 2 and high strength bolts. It may be formed by filling the mortar in the back gap or the gap between the steel pile 2 and the connecting steel material 4, or by fixing the lath wire mesh on the ground slope and mortar and grains on it. You may form by spraying concrete etc. which used the aggregate with a small diameter. When forming the mountain retaining wall surface, among the steel piles 2 described above, steel piles (2 in FIG. 5) other than the steel pile (2a in FIG. 5) forming a triangular top toward the natural ground.
b, 2c), after arranging the distribution reinforcing bars 27 and the like, the steel piles 2b, 2c are wound with cast-in-place concrete in a substantially rectangular cross-sectional shape to form the first-stage prism 13 which is a steel-framed reinforced concrete column. With this structure, the strength is increased and the aesthetic appearance is improved (FIG. 4). In addition, in the above, the cross section of the steel frame reinforced concrete column formed by winding the steel piles 2b and 2c with cast-in-place concrete is not limited to a rectangular cross section, and may have other cross sectional shapes such as a circle and an ellipse. Absent. Alternatively, the steel piles 2b and 2c may be used as pillars as they are without being wound with cast-in-place concrete.

After completion of the above-mentioned first-stage mountain retaining wall plate work, second-stage steel pile connection work is carried out (FIG. 1 (F) or FIG. 4). The second-stage steel pile connecting work is the same as the above-mentioned first-stage steel pile connecting work. When the second-stage steel pile connecting work is completed, next, the first-stage anchor work is performed (FIG. 1 (F) or FIG. 4).

In the first stage anchoring work, first, a hole for the ground anchor 8 is excavated by the anchor hole excavator 35 from above the first stage excavation surface 11 of the natural ground G toward the inside of the natural ground (FIG. 1 (F )). The excavation angle of the anchor hole is determined by the type of excavation, the excavation depth, the slope of the slope, etc., but if the excavation is good, the anchor angle should be laid down (at an angle near horizontal). It is possible. In this case, as the anchor hole excavator 35, an earth auger machine is used when the ground is earth and sand, and a rock drill machine is used when the ground is rock.

When the excavation of the anchor holes is completed, next, the ground anchor 8 is placed, the tension of the anchor and the work of fixing the ground anchor are performed (FIG. 1 (G)). Ground anchor 8
Inserts the PC steel wire 24 deep into the ground, injects mortar or a polymer material, etc. from the tip of the steel wire toward the end to solidify it, forming a long and narrow bulb-shaped portion in the ground.
High tension is applied to No. 4 and it is fixed as it is, and the earth retaining work is sewn to the natural ground.

In the earth retaining method of this embodiment, as shown in FIGS. 4 to 6, the PC steel wire 24 is fixed to the anchor reaction member 25 having a substantially triangular shape by the anchor fixing tool 26. And the anchor reaction force member 25 is
A reaction force is exerted on the steel pile on the natural ground side (located at the top of the triangle facing the natural ground G) of the steel pile 2. It is also possible to apply an anchor reaction force to steel piles other than the above. If the earth pressure is high, such measures will be necessary. The fixing of the ground anchor 8 is performed using an anchor tension fixing device 36 such as a center hole jack (FIG. 1 (G)).

In the above description, an example in which the ground anchor is constructed from the first-stage excavation surface 11 has been described, but this may be conducted from the top of the natural mountain after the first-stage steel pile connecting work is constructed. If such construction is performed, the resistance to natural earth pressure is dramatically increased, and the first stage excavation depth can be made extremely large as compared with the case of the present embodiment.

After the above-mentioned first-stage ground anchor work is completed, next, the second-stage horizontal floor slab work is carried out (FIG. 1 (H) or FIG. 5). The second-stage horizontal floor slab is basically the same as the above-mentioned first-stage horizontal floor slab, but after a protective cap (not shown) is attached to the fixing portion of the first-stage ground anchor described above. Alternatively, they may be buried together in the second horizontal floor slab 9 when cast in place. The protective cap portion may be left outside without being buried in the second horizontal floor slab 9.

After the completion of the second-stage horizontal floor slab, the second-stage earth retaining wall surface 10 is formed while excavating the ground up to the second-stage excavation surface 14 in the same manner as described above (FIG. 1).
(H) or FIG. 5). Hereinafter, similarly, excavation to the flooring surface (final root cutting position) is performed while forming the mountain retaining wall surface.

The present invention is not limited to the above embodiment. The above-mentioned embodiment is an exemplification, has substantially the same configuration as the technical idea described in the scope of the claims of the present invention, and has any similar effect to the present invention. It is included in the technical scope of the invention.

In the above-mentioned embodiment, the earth retaining method of this embodiment has been described as a mountain retaining method for constructing a sloped structure as a permanent structure. However, this is a case of using the mountain retaining method as a temporary structure. It doesn't matter. When used as a temporary work, the earth pressure may be supported by the abdomen uplifting used in ordinary root cutting work and the beam supporting work in addition to the anchor work described above.

Further, in the above embodiment, an example in which a ground anchor is used in combination to suppress the earth pressure of the natural ground has been described, but when the height of the natural ground to be excavated is low or the natural ground is very strong. In such a case, it is also possible to support it by only inserting the steel pile without placing the ground anchor. Therefore, the ground anchor work may or may not be installed as needed.

[0032]

As described above, according to the present invention having the above-described structure, when a plurality of piles are built from the upper part of the natural ground, the piles are arranged in a staggered plane and the ground excavation is performed stepwise. When performing, the exposed parts of the steel piles at each excavation stage are connected so that the planar shape is a substantially triangular shape (a type of truss structure) with the natural ground side as the apex, and by excavation toward the lower part of the natural ground. Since the wall surfaces are formed on the two surfaces of the substantially triangular columnar space that are in contact with the ground, the rigidity of the pile itself and the mountain retaining member is higher than that of the conventional method in which the piles are simply arranged in a line. As a result, for example, it becomes possible to construct a high mountain retaining wall surface having a height difference of 30 m or more, and construction of a cliff surface in a mountainous area can be easily performed. Alternatively, it has an advantage that construction can be easily performed even if the slope of the mountain retaining wall surface is very steep, and the site behind the mountain retaining structure can be effectively utilized. Further, the present invention, from its construction method, and in order to increase its strength, inevitably forms a floor slab in the substantially triangular portion connecting the exposed portions of the steel piles, and this floor slab portion is substantially Since a triangular shelf is formed, it is possible to perform a large-scale treatment of vegetation and the like with the advantage that it has a high degree of freedom. With conventional mountain retaining wall,
According to the present invention, flowers, shrubs, etc. can be planted, for example, by utilizing the above-mentioned shelf surface, although it is at most about turf grass. That is, according to the present invention, it is possible to economically achieve the strength and aesthetics of the mountain retaining work. further,
By adjusting the arrangement of steel piles and span splits, or by properly utilizing steel materials and precast concrete products as materials to be used,
It also has the potential to be advantageous in terms of construction cost compared to the conventional construction method.

[Brief description of drawings]

FIG. 1 is a construction sequence diagram of a procedure of a mountain retaining method which is an embodiment of the present invention.

FIG. 2 is a perspective view showing a state after construction work for building a pile in the mountain retaining method shown in FIG.

FIG. 3 is a perspective view showing a state after rooting work and first-stage steel pile connection work have been carried out in the mountain retaining method shown in FIG. 1.

4 is a perspective view showing a state after construction of a first-stage horizontal slab work, a first-stage earth retaining wall work, a second-stage steel pile connecting work, and a first-stage anchor work in the mountain retaining method shown in FIG. 1. FIG.

5 is a perspective view showing a state after construction of a first-stage horizontal floor slab, a first-stage earth retaining wall work, a second-stage steel pile connecting work, and a second-stage anchor work in the mountain retaining method shown in FIG. 1. FIG.

6 is a plan view showing a more detailed structure of the mountain retaining wall surface and the ground anchor shown in FIGS. 4 and 5. FIG.

FIG. 7 is a cross-sectional view showing a more detailed structure of the mountain retaining wall surface and the horizontal floor slab shown in FIGS. 4 and 5.

[Explanation of symbols]

 1 Pile Hole 2 Steel Pile 3 Rooted Concrete 4 Connecting Member 5 1st Stage Horizontal Floor Slab 6 1st Stage Mountain Cladding Wall 7 Connecting Member 8 1st Stage Anchor 9 2nd Level Horizontal Slab 10 2nd Stage Mountain Clutch Wall 11 1st Step excavation surface 12 First step horizontal beam 13 First step prism 14 Second step excavation surface 15 Second step horizontal beam 16 Second step prism 17 Connecting member 18 Second step anchor 21 Bracket 24 PC steel wire 25 Anchor reaction force member 26 Anchor anchoring tool 27-29 Reinforcing bar 31 Pile hole excavator 32 Pile erection machine 33 Injector 34 Rock excavator 35 Anchor hole excavator 36 Anchor tension anchoring machine G Rock

Claims (1)

[Claims] 1. A mountain retaining method for excavating rocks by building a plurality of piles from the top of the ground, forming a wall surface for preventing the collapse of the ground by using the piles as pillars, and reaching the lower part of the ground. A pile hole excavation process of excavating pile holes arranged in a staggered plane downward from the upper part of the natural ground, a pile building process of subsequently building a steel pile in the pile hole, and then a built-in steel pile. The step of consolidating the piles and the step of performing ground excavation in combination with a ground anchor if necessary, and the exposed portion of the steel pile at each excavation stage has a plan shape whose top is the rock side. Rock excavation in which two slabs are connected to each other in a substantially triangular shape, a floor slab is formed in the substantially triangular portion, and wall surfaces are formed on two surfaces in contact with the natural rock of the substantially triangular columnar space generated by the excavation downward toward the rock. A mountain retaining work characterized by having .