KR20050113450A - Downward reinforced-concrete underground structure using temporary assistant columns - Google Patents

Abstract

According to the present invention, by installing a temporary auxiliary pillar (5) to distribute the load to the support pillar (4), the scale of the support pillar (4) can be reduced, and the size of the steel frame can be reduced. To provide reinforced concrete reinforcement underground structure construction method for small diameter hardening.

In the area where underground structures are constructed, permanent temporary walls using H-beams or permanent walls using underground continuous walls (2) are installed to cope with external forces such as earth pressure and water pressure, and support columns (4) and temporary support columns. After drilling (5) where the standard small H-shaped steel or standardized small steel pipes are to be installed, install the shear connector (7) for load transfer, and then carry out excavation work and install the temporary auxiliary pillar (5). After finishing the reinforcement of reinforced concrete including the column head (6) from the top of the basement floor to the bottom of the structure by reverse casting, the outer wall body (11) and the support column (4) are cast in place to construct the underground structure, and then the temporary auxiliary pillar This method is to complete underground structure by cutting and removing (5).

Due to the nature of the construction method, which is constructed from the ground to the underground, the support pillars (4) are divided into 1st and 2nd stages, and the 1st supports the upper vertical force acting during construction as steel frame of pile concept, and the beams and slabs of the basement floor After the casting is completed, the outside of the steel frame is installed with reinforced concrete columns. Therefore, the steel frame constructed as the primary support pillar (4) needs to be minimized because there is a meaning of the hypothesis, according to the additional installation of the temporary support pillar (4), to minimize the load sharing of the support pillar to be.

Description

Downward reinforced-concrete underground structure using temporary assistant columns

The present invention relates to a construction method (DOWNWARD) for the construction of underground structures to be reinforced concrete reinforcement during construction of the structure, to support the upper load by installing a temporary auxiliary column using the column head to reduce the size of the steel frame of the support pillar to be installed before excavation The present invention relates to a construction method for distributing pillars, finishing supporting columns as reinforced concrete, and then removing temporary auxiliary columns to complete underground structures.

In the construction of underground structures, the main underground structure construction method has been to install temporary temporary wall 15 along the excavation plan line and to support the external force such as earth pressure and water pressure as a support. After the excavation is completed to the foundation floor, each floor structure is constructed sequentially from the bottom to the top, and the permanent construction (underground continuous wall, underground continuous wall) 2) Downward construction of ground structures after completion of underground structures in the same way as the TOP DOWN method, which can be installed on the ground and form composite support pillars as site-pouring piles to perform ground structures simultaneously with underground structures. (DOWNWARD) There is a method.

However, there is a limit to the application of the detachable method. First, in a large site with a large underground structure and a deep excavation depth, it is necessary to support external forces such as earth pressure and water pressure acting on the retaining wall 15, but it is a weak problem for a general retaining wall. Second, there is a problem that the surrounding buildings may be damaged due to the deformation of the retaining wall or ground subsidence due to the outflow of groundwater in the downtown area where the buildings are concentrated. Third, to perform the excavation work and the construction work in the exposed state. Therefore, there are problems of environment and civil complaints caused by noise, vibration, and dust, and the fourth construction period is long because construction works are sequentially performed after the completion of the construction of the earthenware.

In addition, there is a problem in the TOP DOWN method and DOWNWARD method that can solve a lot of problems of the sticking method. First, the underground continuous wall (2) to be installed in the underground will be forced to rebar after vertical excavation by equipment, and then concrete will be changed so that the cross section cannot be changed, but the wall thickness must be constant. Due to the thickness of the wall, the internal area is reduced and there are economic problems of excavation and concrete placing. Second, since the reinforced concrete permanent walls are installed in the ground using large equipment, many construction periods and costs are required due to rock excavation. Third, in the downward method of constructing the basement layer of reinforced concrete structure first, the support column (4) for supporting the upper load is made by using large steel frame, and to install it, large diameter drilling of Φ800 ~ Φ1200 should be performed. It requires time and money.

The first and second of the problems, the inventors can solve this problem by inventing the improved top-down method (Patent No. 0273864) using the general mud wall 15 using the thumb pile (1). there was.

However, there is still a third problem, that is, the drill hole diameter of the RCD cast hole in FIG. 4A is Φ1,500 to Φ3,000, and the drill hole diameter of the PRD cast iron pile in FIG. 4B is Φ800 to Φ1,200. Since it is manufactured in a mold and used, the steel indentation and fabrication by the large-diameter drilling requires precise work and requires a lot of cost and air.

The object of the present invention is to use a standard small H-shaped steel or a standardized small steel pipe for supporting the load (mainly dead load) loaded on the basement floor during construction, especially in the site of the down concrete method of reinforced concrete structure All the loads after the completion of the structure are expanded and supported by RC support pillars by concrete placing. Since the supporting steel used for reverse casting is a temporary concept, it is possible to miniaturize the steel frame and reduce the size of the drilling. It is to provide a method that can greatly reduce costs and air.

One embodiment of the reinforced concrete reinforcement underground structure construction method using a temporary auxiliary pillar to achieve the above object of the present invention, the permanent construction using a temporary soil wall or underground continuous wall using a thumb pile in the area where the underground structure is built In the method of installing walls and entering the support pillar into the ground, and then reinforcing the reinforced concrete structure while excavating for each floor, a temporary auxiliary pillar is placed between the support pillars to reduce or reduce the size of the steel frame of the support pillar. By installing the pit soil and concrete to the floor with each other floor while sharing the upper loads acting on the supporting pillars by each other, and then netting the concrete of the outer wall and the supporting pillar to complete the reinforced concrete basement structure. The temporary auxiliary column is then cut and demolished.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the present invention, the slab and the support pillar are mainly used as the wall and the support body, which mainly consists of the thumb pile (1) acting as the support pillar in the DAWNWARD method after completing the basement of the structure by reverse casting. When constructing the structure while installing (4) and excavating downward, the technical concept is the same as the conventional one.

However, the reverse casting underground structure construction method using the hypothesis secondary pillar of the present invention forms a retaining wall as a thumb pile 1 or a continuous underground wall 2 as shown in FIGS. 5A, 5B, 6A, and 6B, and supports pillars. After installing (4) in the ground, and constructing the reinforced concrete underground structure by gulting work from the top step by step, the supporting column (4) for supporting the upper load is made of steel frame, but according to the large diameter drilling Because large drilling equipment should be used, it is economical and requires a lot of construction periods. It is characterized by the technical construction that it distributes the load of supporting pillar efficiently by installing temporary supporting pillars.

According to an embodiment of the present invention will be described in more detail an embodiment of the reinforcement reinforced concrete tank underground structure construction method using a temporary auxiliary pillar (5) including a column head.

First, as shown in Figure 6b to install the temporary auxiliary pillar (5) to share the load of the support pillar (4) to reduce the number of installation of the temporary auxiliary pillar can be used as the equipment was drilled when installing the thumb pile (1) The standardized small H-beam or standardized small steel pipe can be used, and it is calculated by considering the upper load acting according to the size of the basement. The installation position of the temporary auxiliary pillar (5) is determined by the supporting column (4) and the upper load. Select the place where it can be distributed evenly and do not interfere with the construction work, and make the perforation while maintaining the verticality in consideration of the allowable eccentricity so that the supporting pillar and the temporary supporting pillar are not buckled.

In order to install the verticality of the column precisely, install the first guide casing, fix it with concrete, and then install the second guide casing. Verticalness is checked on site as inspection equipment.

The temporary auxiliary column 5 of FIG. 7 is installed to distribute the upper load with the supporting column 4, and the temporary auxiliary connecting structure of the column and the slab uses the shear connector (STUD, 7), but is connected to the slab as it is. As the slab thickness of the structure is shallow, it is difficult to transfer the load and can be punched. Therefore, the DROP PANEL 6 is installed on the structure slab to smoothly transfer the load as the shear connector 7. The number of shear connectors and the width and thickness of the column heads are determined by the sharing load. Shear connector is based on the use of a stud (STUD), but various structures or shapes, such as ring-shaped or H-shaped steel can be used if necessary.

As described in the prior art, the conventional RCD cast-in-place pile boring diameter as shown in FIG. 4A is Φ1,500 to Φ3,000, and the drill diameter of the PRD cast-in-place pile in FIG. 4B is Φ800 to Φ1,200. It is manufactured and used in a box shape. Steel intrusion and production by such a large diameter drilling requires precise work, high cost and air.

8A and 8B are cross-sectional and detailed views of the hypothetical support pillar 5 and the support pillar 4, with the drill pile 16 of the perforated wall 1 having a hole diameter 16 of Φ 500 or less, much smaller than that of the RCD or PRD. It is also possible to use standardized small H-beams or standardized small steel pipes.

9A to 9H are construction flowcharts of one embodiment of the present invention. First, Figure 9a is a general earth wall installation diagram, H-shaped steel into the ground (14) as the thumb pile (1), and the sediment section is subjected to the heat-stacked pile and grouting for order and ground reinforcement.

FIG. 9B is a drawing of the installation of the underground continuous wall, the trench cut in the ground (14) to maintain the excavated hollow wall as a stabilizer, assemble and reinforce the reinforcing bars, and then cast concrete to install the permanent wall into the underground continuous wall (2) Form.

Then, in Fig. 9c, after general drilling at the position of the temporary support pillar (5) and the support pillar (4), the standardized small H-shaped steel is introduced and the shear connector 7 is installed, and then the excavation bottom is poured concrete. Secure the column as a pile foundation.

In Fig. 9d, a small perforated steel pipe standardized at the positions of the temporary supporting column 5 and the supporting column 4 is inserted, and grouting is carried out to obtain the required ground supporting force as the main surface and the end support. To fix the column.

As shown in FIG. 9E, the temporary auxiliary pillar 5 and the support pillar 4 are provided with a shear connecting member 7 to facilitate load transfer, and the shear connecting member 7 installed at the column head 6 is provided. The shear connector, which is installed for the purpose of load transfer and is installed in advance at the tip, has the purpose of supporting the load on the ground as a pile.

Then, as shown in Fig. 9f, excavation and reinforcement of the reinforced concrete including the column head 6 at the upper basement floors are repeated and finished as a foundation.

After finishing the foundation in this way, the outer wall and the support column 4 was constructed as a small steel frame in order to reduce the upper load, but after the completion of excavation and foundation construction, as shown in Figure 9g sequentially from the lowest layer to the upper layer and the outer wall and The concrete of the supporting column is poured to complete the reinforced concrete underground structure.

Since the function of the temporary auxiliary pillar used to assist in reducing the upper load is completed, the temporary auxiliary pillar 5 is removed as shown in FIG. 9H and the structural part of the ground 13 is constructed.

As described above, according to the construction and operation of the reinforced concrete reverse casting underground structure construction method using the temporary auxiliary pillar of the present invention, the temporary auxiliary pillar (5) using the column head together with the supporting column (5) in the underground structure construction By installing and constructing, it is possible to miniaturize the steel frame of the support pillar (5) and to reduce the diameter of the hole diameter during the excavation construction, so that the construction cost can be greatly reduced, and accordingly, the construction of the construction such as air shortening is smooth and stable. And economically advantageous. In addition, in the case of using the thumb pile (1), it is possible to use the equipment drilled when the thumb pile (1) is installed as it is, it is more effective to use a standardized small H-shaped steel or a standardized small steel pipe.

1A and 1B are some schematic top views of a prior art embodiment.

2A and 2B are some schematic cross-sectional views of a prior art embodiment.

3A and 3B are cross-sectional views of the cast-in-place pile of the prior art embodiment.

4A and 4B are longitudinal partial cross-sectional views of the cast-in-place pile of the prior art embodiment.

5A and 5B are partial plan views of embodiments of the present invention.

FIG. 6A is a schematic partial cross-sectional view of a support pillar and a temporary auxiliary column using small H-shaped standardized steel, and FIG. 6B is a schematic partial cross-sectional view of a support pillar and a temporary auxiliary column using a small standardized steel pipe.

7 is a cross-sectional view of the pillar head portion of the temporary support pillar of FIG. 6A or 6B.

Fig. 8A is a cross sectional view of a standardized small H-beam of a support column and a temporary support pillar, and FIG. 8B is a cross-sectional view of a standardized small steel pipe of a support column and a temporary support pillar.

9A to 9H are schematic diagrams showing the construction sequence of an embodiment according to the present invention.

<Description of the symbols for the main parts of the drawings>

1: thumb pile 2: underground continuous wall

3: columnar pile 4: support column

5: Temporary Auxiliary Column 6: DROP PANEL

7: Shear connector (STUD) 8: Perforated steel pipe

9: R.C support pillar 10: each layer slab

11: outer wall 12: foundation concrete

13: Ground 14: Underground (Underground)

15: Hypothesis wall 16: Perforation

Claims (5)

Reinforced concrete structures are installed in the area where the underground structures are constructed by installing temporary walls (15) using permanent piles (1) or permanent walls using underground continuous walls (2). In the construction method of inverse pouring the construction, In order to reduce or reduce the size of the steel frame of the support pillar 4, a temporary auxiliary pillar 5 is installed between the support pillars 4, thereby sharing the upper loads acting on the support pillars 4 with each other. After constructing the concrete to the floor by back-pouring, the concrete of the outer wall body and the support pillar 4 is completed, and the reinforced concrete-based underground structure is completed, and then the temporary auxiliary column 5 is cut and demolished. Reinforced concrete reinforcement underground structure construction method using temporary support pillar. The support pillar (4) and the temporary support pillar (5) can be drilled by small diameter by using small steel, and can be used as a small steel standardized small H-shaped steel and / or steel pipes Reinforced concrete reinforcement underground structure construction method using temporary support pillar. The temporary support pillar (5) and / or support pillar (4) according to claim 2, in the case of the temporary soil wall (15) using the thumb pile (1), the equipment that was drilled at the time of installing the thumb pile (1) as it is It can be used as a small steel standardized small H-shaped steel and / or standardized small steel pipe, and it is possible to equally distribute the upper load acting according to the size of the basement layer with the supporting pillar (4) and do not interfere with the construction work. Reinforced concrete reinforcement underground structure construction method using a temporary auxiliary pillar, characterized in that to set the installation quantity and / or installation position so as not to. 2. The shear connecting material (7) according to claim 1, wherein the column head (6) is installed in the structural slab of each layer around the temporary supporting column (5) within the height of the beam, and is coupled with the column head (6). Reinforced concrete reinforcement underground structure construction method using a temporary auxiliary pillar, characterized in that installed on the auxiliary pillar (5) to smoothly transmit and support the load. The method according to claim 1, wherein in order to obtain the ground bearing force of the supporting column (4) and the temporary supporting column (5), concrete is cast after the shear connector is pre-installed at the end of the H-shaped steel. Temporary auxiliary pillar, characterized in that the steel pipe is perforated, perforated to remove slime and infiltrate the steel pipe, and then grouting to secure the support force and tip support force by the outer circumferential surface friction and to fill the interior with concrete. Construction of Reinforced Concrete Underground Structures Using Reinforced Concrete Structures.