JPH09268583A - Structural steel embedded half precast concrete member and construction method of underground structure using the same member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the need for overbreak and backfill and avoid concrete placement in muddy water and enhance quality control and eliminate the need for earth retaining member, such as steel sheet piles on the outer peripheral part of a structure and upgrade the quality of skeleton concrete and satisfy the requirements of mutual structural integrity of precast concrete member and contribute toward cost and construction period reduction. SOLUTION: A ditch is excavated at a position at which an exterior wall of an underground structure is constructed. Witch a structural steel which is a structural steel embedded half precast concrete member as a soldier pile, an exterior wall unit panel 1 which uses the precast concrete board as a horizontal lagging is connected to each other one after another while being pile-positioned, thereby setting the panels 1. After the setting up is completed, this exterior wall unit panel 1 is a structural steel embedded half precast concrete used as an earth retaining wall. While being supported with a floor board unit panel 5 of the underground structure which uses the structural steel as a strut, excavation is being made. When the structure is completed, the exterior wall unit panels 1 and the floor board unit panels 5 are used as an exterior wall and a floor board of each main body structure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel frame embedded type half precast concrete member which also serves as a formwork and a method for constructing an underground structure using the same.

[0002]

2. Description of the Related Art Conventionally, when constructing an underground structure such as an underground tunnel, a common ditch, or an underground parking lot, a pile member such as a steel sheet pile is driven on the outer periphery of the structure or a continuous underground The wall is constructed with cast-in-place concrete to construct a mountain retaining wall, and while excavating the inside, angry up to the mountain retaining wall. After excavation, the structures were either cast in-place concrete or precast structural members were assembled.

However, when a mountain retaining wall such as a steel sheet pile is provided, it must be installed away from the structural body, which requires extra excavation and backfilling after the completion of the body.
On the other hand, the continuous underground wall can be used as the main body of the structure to eliminate overburden and backfilling, but since it is concrete pouring in muddy water, quality control is difficult, and it is used as the main body of the structure alone. It was difficult. Therefore, in order to eliminate such a drawback of the conventional construction method, a method of using a precast concrete member as the continuous underground wall and utilizing it for the mountain retaining wall and the main body wall can be considered.

[0004]

However, since the conventional precast concrete member is a full precast concrete member for the outer wall of the main body structure, it requires a considerable member thickness to support the load over a long span. For example, if the internal effective height of an underground structure is 5 to 6 m, a wall thickness of 50 cm or more is required to construct a continuous underground wall with full precast concrete members, so work to transport it from the factory to the site is required. Considering this, the size of the unit panel is reduced to about 1 m in width. The construction of a structure with such subdivided unit panels has a drawback that many seams are generated.

Further, in order to use the continuous underground wall of the full precast concrete member in the main body structure, each vertical joint portion must satisfy the structural integrity and sufficient waterproofness. However, the method of joining the full precast concrete members and the method of waterproof treatment have to be technically solved, and there is a possibility that quality problems may occur.

The present invention solves the above problems, and even for a precast concrete member having a long supporting span, the thickness of the precast concrete member is relatively thin, the weight per unit width is light, and the acting load is sufficient. The number of joints of the structure that can be supported is reduced, and the remaining part of the half-precast concrete member is cast-in-place concrete, so that the structural integrity of the structure and the waterproofness can be sufficiently satisfied. It is an object to provide a mold half precast concrete member.

[0007] In addition, by eliminating overburdens and backfilling, avoiding concrete pouring in muddy water, quality control is improved, and no pile retaining members such as steel sheet piles are required on the outer periphery of the structure, and the quality of skeleton concrete is improved. It is also an object of the present invention to provide a method for constructing an underground structure using a steel frame-embedded half precast concrete member, which is highly expensive and fully satisfies the structural integrity of the precast concrete members, and contributes to cost reduction and construction period reduction.

[0008]

In order to solve the above-mentioned problems, the invention according to claim 1 is a plate-shaped precast which doubles as a formwork for post-cast concrete and is integrated with the concrete after the concrete is poured. A steel member for supporting a load acting on the precast concrete member is characterized in that a part of the steel frame is embedded in the precast concrete member at a predetermined interval and the rest is projected.

Even for a precast concrete member having a long support span, the steel frame supports the load acting on the precast concrete member, so that the plate thickness of the concrete can be reduced and the weight per unit width is reduced. Further, the steel frame is embedded in the post-cast concrete, and also has the effect of improving the structural integrity of the precast concrete members and the waterproofness. Moreover, the applied load can be sufficiently supported, and the number of joints of the structure to be constructed is reduced.

Further, the invention according to claim 2 excavates a groove at a position for constructing an outer wall portion of an underground structure, and successively connects while building an outer wall unit panel of a half precast concrete member in the groove. After the installation of the outer wall unit panel is completed, the outer wall unit panel is used as a mountain retaining wall and root cutting is performed while supporting it by supporting works, and then the reinforcement of the remaining main structural part of the half precast concrete member and concrete placement are done on site. When the construction is completed and the structure is completed, the outer wall unit panel is used as an outer wall of the main body structure, and the outer wall unit panel is the steel-frame-embedded half precast concrete member according to claim 1, wherein the steel frame is used as a parent pile for precast concrete. It is characterized in that it is a unit panel with a horizontal sheet pile.

The steel frame embedded half precast concrete member according to claim 1, wherein installation of an outer wall unit panel using steel frames as a main pile and a precast concrete plate as a horizontal sheet pile is completed, and this outer wall unit panel is used as a mountain retaining wall. Therefore, a mountain retaining member such as a steel sheet pile is not required on the outer peripheral portion of the structure.
When the structure is completed, the outer wall unit panel can be used as the outer wall of the main body structure, the structural integrity of the outer wall unit panels can be sufficiently satisfied, and the cost and the construction period can be reduced.

Further, in the invention according to claim 3, a groove is excavated at a position where an outer wall portion of an underground structure is constructed, and outer wall unit panels of a half precast concrete member are built in the groove and are sequentially connected to each other, and After the installation of the outer wall unit panel is completed, the outer wall unit panel is used as a mountain retaining wall and root cutting is performed while supporting it by supporting works, and then the reinforcement of the remaining main structural part of the half precast concrete member and concrete placement are done on site. When the construction is completed and the structure is completed, the outer wall unit panel is used as an outer wall of the main body structure, and the outer wall unit panel is the steel-frame-embedded half precast concrete member according to claim 1, wherein the steel frame is used as a parent pile for precast concrete. It is a unit panel in which the board is a horizontal sheet pile, and the supporting work is a floor board of a half precast concrete member. The floor panel unit panel is a steel frame embedded half precast concrete member according to claim 1, wherein the steel frame is used as a cutting beam, and the remaining main structure portion of the half precast concrete member is reinforced and placed in concrete. It is characterized by being used as a floorboard of the main structure when it is constructed on site and the structure is completed.

Root cutting is performed by using the floor panel unit panel of the underground structure of the steel frame embedded type half precast concrete member according to claim 1, wherein the outer wall unit panel is a mountain retaining wall, and the steel frame is a truss. After that, the reinforcement and concrete placement of the remaining main structural part of the half precast concrete member is done on-site, and when the structure is completed, the outer wall unit panel and floor plate unit panel can be used as the outer wall and floor plate of the main structure, respectively. It is possible to fully satisfy the structural integrity between the panel and the floor panel unit panel, which contributes to cost reduction and shortening of the construction period.

According to a fourth aspect of the present invention, the outer wall unit panel is installed, and the middle wall unit panel of the half precast concrete member is installed at a predetermined position by the same procedure. While supporting the unit panel by supporting work, root cutting is performed, and then the reinforcement and concrete placement of the remaining main structural part of the half precast concrete member is done on site, and when the structure is completed, the outer wall unit panel and the middle wall unit Each of the panels is used as an outer wall and an inner wall of the main body structure, and the inner wall unit panel is the steel-frame-embedded half-precast concrete member according to claim 1, like the outer wall unit panel.

The steel frame embedded half-precast concrete member according to claim 1 is installed as an outer wall unit panel and an inner wall unit panel while being sequentially connected to each other to complete the installation, and the outer wall unit panel and the inner wall unit panel are supported by supporting work. While doing root cutting, after that, the reinforcement of the remaining main structure part of the half precast concrete member and concrete placement are done on site, and when the structure is completed, the outer wall unit panel and the inner wall unit panel are attached to the outer wall and the middle of the main structure. It can be used as a wall, sufficiently satisfying the structural integrity between the outer wall unit panel and the inner wall unit panel, and can contribute to cost reduction and shortening of the construction period.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Next, a steel frame embedded type half precast concrete member of the present invention and a method of constructing an underground structure using the same will be described with reference to the accompanying drawings. FIG. 1 is an explanatory view of an underground structure using a steel frame embedded half precast concrete member for a continuous underground wall, FIG.
3 and 4 are respectively a II-II section, a III-III section and a section of FIG.
5 is a detailed cross-sectional view of the outer wall portion, FIG. 6 is an enlarged view showing a part of FIG. 5, FIG. 7 is an enlarged view showing a b part of FIG. 1, and FIG. 8 is the same. It is a perspective view of a part.

The steel frame embedded type half precast concrete member used in this embodiment will be described with reference to FIGS. 2 to 4. FIG. 2 shows an outer wall unit panel 1 used as a continuous underground wall, but a half precast concrete member 2
In this structure, a plurality of H-shaped steels 3 are embedded at a predetermined interval d, and a part of the web of the H-shaped steels 3 and one flange are provided so as to project from the plate surface. Since the outer wall unit panel 1 is used as a retaining wall, the H-shaped steel 3 has a cross-sectional performance required as a parent pile, and the half precast concrete member 2 has a cross-sectional performance required as a transverse sheet pile. Therefore, the cross-sectional performance required as the outer wall when the structure is completed can be realized by reinforcing the required reinforcing bars and the post-cast concrete 4, so that the plate thickness of the concrete can be reduced.

FIG. 3 shows a floor panel unit panel 5 which also serves as a support, and FIG. 4 shows a middle wall unit panel 6 which also serves as a shelf pile, both of which are in the half precast concrete members 7 and 8 like the outer wall unit panel 1. This is a structure in which a plurality of H-shaped steels 9 and 10 are buried. The H-shaped steel 9 of the floor panel unit panel 5 is used as a cross beam,
The H-shaped steel 10 of the middle wall unit panel 6 has the cross-sectional performance required as a shelf pile. The floor plate unit panel 5 and the middle wall unit panel 6 become the floor plate and middle wall of the main body structure by the required reinforcement and post-cast concrete 4.

When constructing an underground structure using such a steel frame-embedded half precast concrete member, first, a groove is formed at a position where an outer wall portion of the underground structure is constructed by an excavator for continuous underground wall excavation. Excavate. Next, the outer wall unit panel 1 is built in the groove using a lifting machine. Details of the outer wall unit panel 1 will be described with reference to FIGS. 5 and 6. In the outer wall unit panel 1, an H-shaped steel 2b for connection is embedded in one of the vertical joint portions of the half precast concrete member 2 having a reinforcing bar 2a having a cross section required as a main body structure, and the flange thereof is projected. Light groove type steel 2c with a lip that can engage this flange is embedded in the other vertical joint portion.

After the first outer wall unit panel 1 is installed, the vertical joints of the adjacent outer wall unit panels 1 are sequentially assembled in the groove while being connected. The inner wall unit panel 6 is also installed at a predetermined position by the same procedure. Next, the primary excavation is performed up to the height shown in FIG. 1, and the floor panel unit panel 5 is connected to the outer wall unit panel 1. Details of this connecting portion will be described with reference to FIGS. 7 and 8. Plates 3a and 3b for connection are provided on the upper portion of the H-shaped steel 3 of the outer wall unit panel 1 so as to project from the flange surface, and a slit 3c is formed in the upper plate 3a so that the web of the H-shaped steel 9 can be inserted. . While placing the end of the H-shaped steel 9 of the floor plate unit panel 5 on the lower plate 3a, the slit 3 of the upper plate 3a is placed.
Insert into c and weld and connect both. In addition, the reinforcing plate 3 is provided on the H-shaped steel 3 of the outer wall unit panel 1.
d is fixed.

After the floor panel unit panel 5 is installed, the floor board 17 is constructed by excavating to the floor mounting position. The floor panel unit panel 5 acts as a girder for a mountain retaining rod, and also has a function as a roof covering a work place, so that the working environment inside is improved. When excavating, the outer wall unit panel 1
A caulking material 2d for stopping water is applied to the seam. next,
The required reinforcing bars and post-cast concrete 4 are placed inside the outer wall unit panel 1 to complete the outer wall as the main body structure. In this case, as shown in FIG. 5, the outer wall unit panel 1
Form fastening metal fittings 19 are fixed to the H-shaped steel 3 and the half precast concrete member 18 also serves as a form on the inner surface of the structure.
Is established. The post-cast concrete 4 is placed inside to integrate the two.

Since the post-cast concrete 4 which is continuous inside the outer wall unit panel 1 is integrally constructed, there is no seam, structural integrity is satisfied, and water stopping performance is improved. In addition, the outer wall unit panel 1 is used as a mountain retaining wall and root cutting is performed while supporting it by the support work, and when the structure is completed, the outer wall unit panel is used as the main body structure. It may be a truss or an earth anchor.

[0023]

As described above, according to the first aspect of the present invention, since the steel frame-embedded half precast concrete member has the steel frame for supporting the load, the steel frame-embedded half is supported even if the supporting span is long. Precast concrete member thickness is relatively thin and the weight per unit width is light, the number of joints of the structure to be constructed can be reduced, and the remaining part of the steel-frame-embedded half precast concrete member is cast-in-place concrete Therefore, it is possible to improve structural integrity and waterproofness.

The invention according to claim 2 is the half-precast concrete member for embedding a steel frame according to claim 1, in which outer wall unit panels having steel frames as parent piles and precast concrete as horizontal sheet piles are successively connected while being built, Since the installation of the unit panel is completed and the outer wall unit panel is used as the mountain retaining wall, a mountain retaining member such as a steel sheet pile is not required on the outer peripheral portion of the structure. When the structure is completed, the outer wall unit panel can be used as the main body structure, and the structural integrity of the outer wall unit panels can be sufficiently satisfied, which can contribute to cost reduction and shortening of the construction period.

According to a third aspect of the present invention, the outer wall unit panel is a mountain retaining wall, and the steel frame embedded half precast concrete member according to the first aspect is a floor board unit panel of an underground structure having a steel beam as a cutting beam. Since it can be used as a construction work for root cutting and the floor panel unit panel can be installed in the initial stage of excavation, it contributes to the improvement of the working environment inside and the quality of the skeleton concrete.

According to a fourth aspect of the present invention, the half-precast concrete member embedded with a steel frame according to the first aspect is installed as an outer wall unit panel and an inner wall unit panel while being sequentially connected to each other to complete installation. While supporting the wall unit panels by supporting work, root cutting is performed, and then the reinforcement and concrete placement of the remaining main structural part of the half precast concrete member is done on site, and when the structure is completed, the outer wall unit panel and the middle wall unit panel Can be used as the outer wall and the middle wall of the main body structure, respectively, and the structural integrity of the outer wall unit panel and the middle wall unit panel can be sufficiently satisfied, which can contribute to cost reduction and shortening of the construction period.

[Brief description of drawings]

FIG. 1 is an explanatory view of an underground structure using a steel frame embedded half precast concrete member.

FIG. 2 is a sectional view showing a section taken along line II-II in FIG.

3 is a cross-sectional view showing a cross section taken along line III-III in FIG.

FIG. 4 is a cross-sectional view showing a cross section taken along the line IV-IV in FIG. 1.

FIG. 5 is a detailed cross-sectional view of the outer wall portion.

FIG. 6 is an enlarged view showing part a of FIG.

FIG. 7 is an enlarged view showing part b of FIG. 1.

FIG. 8 is a perspective view of portion b of FIG.

[Explanation of symbols]

 1 Outer wall unit panel 2 Half precast concrete member 3 H type steel 4 Post-cast concrete 5 Floor board unit panel 6 Middle wall unit panel

Claims (4)

[Claims] 1. A plate-like half-precast concrete member which doubles as a formwork for post-cast concrete and is integrated with the concrete after the concrete is poured, for supporting a load acting on the half-precast concrete member. A steel-frame-embedded half precast concrete member, wherein a part of the steel frame is embedded in the half precast concrete member at a predetermined interval and the rest is projected. 2. A groove is excavated at a position where an outer wall portion of an underground structure is constructed, and outer wall unit panels of a half precast concrete member are built in the groove and sequentially connected to each other to complete the installation of the outer wall unit panel. Later, root cutting was performed while supporting the outer wall unit panel as a mountain retaining wall with support work,
After that, on-site construction of the rebar and concrete placement of the remaining main structure part of the half precast concrete member,
When the structure is completed, the outer wall unit panel is used as an outer wall of the main body structure, and the outer wall unit panel is the steel-frame-embedded half precast concrete member according to claim 1, and the steel frame is used as a main pile to form a precast concrete plate horizontally. A method for constructing an underground structure using a steel frame embedded half-precast concrete member, which is a unit panel made of sheet pile. 3. A groove is excavated at a position where an outer wall portion of an underground structure is constructed, and an outer wall unit panel of a half precast concrete member is built in the groove and sequentially connected to complete the installation of the outer wall unit panel. Later, root cutting was performed while supporting the outer wall unit panel as a mountain retaining wall with support work,
After that, on-site construction of the rebar and concrete placement of the remaining main structure part of the half precast concrete member,
When the structure is completed, the outer wall unit panel is used as an outer wall of the main body structure, and the outer wall unit panel is the steel-frame-embedded half precast concrete member according to claim 1, and the steel frame is used as a main pile to form a precast concrete plate horizontally. It is a unit panel used as a sheet pile, The said support work is a floor board unit panel of a half precast concrete member, This floor board unit panel is a steel-frame-embedded half precast concrete member of Claim 1, Comprising: , Steel prefabricated half-precast concrete members, which are used as floorboards for the main structure when the structure of the remaining main structure part of the half-precast concrete member is reinforced and concrete is placed on site and the structure is completed. How to build an underground structure. 4. Along with the installation of the outer wall unit panel, the middle wall unit panel of the half-precast concrete member is installed at a predetermined position by the same procedure, and the outer wall unit panel and the middle wall unit panel are supported by supporting work. While doing root cutting, after that, the reinforcement of the remaining main structure part of the half precast concrete member and concrete placing are done on site, and when the structure is completed, the outer wall unit panel and the inner wall unit panel are respectively the outer wall of the main structure And the inner wall unit panel is the steel-frame-embedded half-precast concrete member according to claim 1, which is used as the inner wall, and the inner wall unit panel is the same as the outer wall unit panel. Construction method of underground structure using steel frame embedded half precast concrete member.