KR20100000854A - Enlarged endbearing capacity foundation using cone and it's construction work method - Google Patents

Abstract

PURPOSE: An enlarged end bearing foundation using a cone base and a construction method thereof are provided to improve the end bearing capacity of the cone basis by enlarging the cross section of the tip of the post or pile. CONSTITUTION: A construction method of an enlarged end bearing foundation using a cone base comprises the steps of: deciding a base installation position, positioning a cone base(300) in the decided installation position, driving the cone base through a self-drilling hole by rotating and pressing, and injecting grout or concrete into a hollow post(100) and the receiving part of the cone base.

Description

Extended tip support base using cone foundation and construction method {ENLARGED ENDBEARING CAPACITY FOUNDATION USING CONE AND IT'S CONSTRUCTION WORK METHOD}

In addition to industrial development, various facilities and structures as well as residential facilities are needed, and thus various types of foundations are required to safely support these structures.

In recent years, there have been many cases in which structures have to be installed on soft soils such as river alluvial layers composed of soft fine-grained soils and coastal tidal flats, as well as high quality soils, and various construction methods are required to safely install foundations on such soft soils.

The most commonly used foundation methods are footing foundation and pile foundation.

Expanded foundation is the most common and simple method of direct footing or shallow footing, where the high quality ground is relatively close to the surface, which enlarges the foundation section to increase the bearing capacity. Since the ground is not located near the surface of the ground, it is a representative method of deep foundation that transfers the load through the pile to the good ground in the ground.

The present invention relates to a construction method that can be used for these two types of foundation, the installation of the expansion base, but excavating the ground to the place where the foundation is located, the foundation is installed and then backfilling to position the foundation at a predetermined position Unlike the traditional method, the foundation is installed by reinforcing the cone-shaped reinforced foundation with the cross section of the enlarged foundation, but after the installation, the foundation is grouted in the cone foundation to complete the foundation or grouting the cured foundation. It is a simple and economical method that eliminates artificial work such as excavation or backfilling by positioning the foundation on high quality ground to complete the foundation.In the case of pile foundations, it has a larger end section than the pile cross section. With regard to the expansion tip support base using cone foundation and its construction method which greatly increased bearing capacity The.

Most structures are located on high quality ground.

In order to be placed on a good ground, a foundation is installed under the structure, which is planned to keep the structure safe.

These foundations can be divided into shallow foundations and deep foundations, depending on whether high-quality grounds capable of holding the structure are located near the earth's surface.

The shallow foundation is a technique that transfers the load of the structure directly to the high quality ground.

Expanding foundation is the most widely used method to reduce the load per unit area and increase the bearing capacity by enlarging the base surface in contact with the high quality ground.

The deep foundation is a method of installing other structures such as piles to transfer the load of the structure to the high quality ground because the high quality ground is relatively deep on the ground, and there are pile foundations. If the good soil is located at a depth of about 4 to 5 times the foundation width, it can be classified as a deep foundation.

The enlarged foundation is excavated from the ground surface to the point where the foundation is located, and then the formwork is placed on the foundation section, reinforced with reinforcement such as reinforcing bars, then cast concrete, cured, and then backfilled to complete the load. While the foundation section is larger than the column, it is advantageous in terms of bearing capacity, but it requires a series of processes such as excavation and formwork, reinforcing steel reinforcement, concrete placement, curing and formwork removal, and backfilling, especially through soft ground. When the foundation is installed, the excavation surface is easily collapsed during the excavation of the ground, so it is necessary to excavate the ground with a gentle slope so as not to install a separate temporary facility or to collapse it. There is a problem that becomes complicated.

Pile foundations are made by striking the pre-fabricated piles to high quality ground and perforated by augers, etc., and then pre-fabricated piles are installed in the drill holes or concrete is poured directly into the drill holes in the field. Can be divided in a way.

The pile foundation is a method that transfers the load of the structure to the high quality ground through the pile and obtains the supporting force of the foundation by the sum of the tip support of the pile end and the friction support around the pile, which is difficult to enlarge the foundation cross section. If the cross section is large, it is difficult to install, so it is generally required to install several piles with small cross-sections. Therefore, noise and vibration are a problem when installing piles. Since the number of pile installations is increased as compared to the case of installing piles, there is a problem such that the cost is greatly increased compared to the expansion foundation.

If the driving is not possible due to the noise and vibration problems at the time of driving, the drilling method is to use the perforated pile foundation method, in which a perforator such as an auger is installed and a pile is installed in this case. As small piles are installed, frictional support becomes smaller than that of driving type, and slime builds up in the lower part of the drilled hole, which reduces the complex bearing power. Excavation and rotationally press-fit the pile with screws ('Pile method of screw with conical tip' of Korean Patent Publication No. 10-0396393), or increase the frictional cross-section by partially attaching the attached section (Korea Patent Publication No. 10-0690014 'Steel Structure with Spiral Plate'.

In this case, by installing piles with screws, it is possible to restrain the reduction of frictional support compared to the conventional drilling method, but in the case of soft ground, the tip support appearing at the end of the pile mainly depends on the size of the support. Considering the fact that it is necessary to increase the tip area of the pile in order to increase the bearing capacity, there is a limit to this, and the method of increasing the cross section of the frictional resistance by partially increasing the attachment cross section disturbs the ground during installation. Although the frictional resistance per unit area is reduced and the attached cross section is enlarged, the effect is limited to design consideration.

On the other hand, in order to increase the bearing capacity of piles, there is a method of reinforcing the ground by injecting mortar into it when the foundation is soft (Korean Patent Publication No. 10-0792130, 'Push-in Steel Pipe Pile Method'). In the case of a small diameter micro pile method that minimizes the effect, a method of increasing the stability of the ground by pressurizing grout injected into the drilling hole to increase the bearing capacity (Korean Patent Publication No. 10-0779988 The method of pile construction ') increases the effect of pile foundation. In this case, the injection of grout into the ground is highly dependent on the condition of the ground, and in general, grout such as cement paste or mortar in the ground is used to facilitate the injection of grout. Since the voids or gaps in the ground can be large, the actual injection is difficult. In this case, there is a problem that it is difficult to confirm the pressurization effect. In general, the method of mixing the mortar with the excavated ground is often used. Therefore, it is limited to increase the bearing capacity of the foundation by expanding the base end portion. There is no choice but to.

Expansion tip support base and construction method using the cone foundation of the present invention to solve the problems occurring in the prior art as described above, conventionally refilling the ground after artificially excavating the ground and installing the expansion foundation by placing concrete Contrary to the method, the excavated ground is directly excavated with a cone-shaped expansion foundation and placed on a predetermined high quality ground, and then the grout material such as cement mortar is filled inside the cone-shaped foundation, or the cone foundation is pre-grouted or concrete Forming and inserting in the form of cones and pillars by using the consequently, the expansion base can be installed more easily than the conventional method, thereby preventing the occurrence of loosening or displacement of nearby ground or structure due to excavation, and the process of excavation and backfilling To provide a foundation that is economical and easy to construct and its construction method. All.

More specifically, in the case of pile foundations, it is difficult to increase the tip bearing capacity because the foundation cross-section is small, and consequently, a large number of pile foundations have to be installed. Although grout is being carried out to secure the effect, it is not only easy to secure accurate tip bearing capacity but also the number of piles can be significantly reduced by installing a foundation having a pre-calculated cross section in a state of doubt about its effect. The economic effect is great, and the installation method is simple, so that it is easy to secure the bearing capacity of the pile foundation.

In order to solve the above problems, the expanded tip support base and the construction method using the cone foundation of the present invention, in the expanded tip support base construction method, position selection step of arranging the foundation installation position after arranging the foundation installation ground ; After the pillar is installed in the upper part, the upper part has a diameter larger than the diameter of the column, and is formed in the shape of a cone that gradually decreases in diameter as it goes to the lower part. A perforation step of perforating the foundation to a predetermined depth using rotation and indentation; The grout step of injecting grout material or concrete into the interior of the column and the receiving portion of the cone base after reaching a predetermined depth.

At this time, while rotating the cone base in the grout step, the base is filled with grout material or concrete in the upper part of the cone base by grouting by using the accommodating part of the empty space inside the cone base to easily relax the upper soil. It is characterized by completing.

In addition, the upper portion of the cone base is characterized in that 2 to 5 times larger than the diameter of the pillar.

In addition, the cone base is made of any one material of steel or reinforced plastics, and the deformation preventing member is installed therein so that it is not deformed or destroyed in the process of being inserted through rotation and pressing, and the deformation preventing member is inside Is empty and is formed in a form in which a hole is formed on the outer circumferential surface.

Extended tip support base of the present invention constructed by the above construction method, the pillar is inserted into the ground; A cone base installed in the lower part of the pillar, the upper part having a diameter larger than the pillar diameter, and formed in a cone shape gradually decreasing in diameter as it goes down; It is composed of grout or concrete filled inside the pillar and inside the cone foundation.

In addition, another enlarged tip support foundation construction method of the present invention, after selecting the foundation installation location after the foundation installation ground location selection step; A pillar formed of cured grout material or concrete is installed in the upper part, and the upper part has a diameter larger than the pillar diameter, and is formed in the form of a cone gradually decreasing in diameter as it goes down, and preparing a cone foundation formed by curing the grout material or concrete. Preparation step; It comprises a step of drilling the prepared cone foundation to a predetermined depth through rotation or indentation.

At this time, it is characterized in that the pipe is provided on the outside of the pillar, or the case of steel or synthetic resin material is installed on the outside of the cone base.

In addition, the upper portion of the cone base is characterized in that 2 to 5 times larger than the diameter of the pillar.

The expanded tip support base of the present invention constructed by another construction method as described above, is inserted into the ground, the pillar made of a hardened grout; It is installed in the lower part of the pillar, the upper portion has a diameter larger than the diameter of the pillar, and is formed in the form of a cone gradually decreases in diameter as it goes to the bottom, the base of the cone consisting of a cured grout; characterized in that consisting of.

According to the present invention, unlike the conventional method of artificially excavating the ground and placing concrete to install and then backfilling, the cone-based enlargement foundation is directly excavated and placed on a predetermined high quality ground. Next, the grout or concrete, such as cement mortar, is filled inside the cone-shaped foundation, or the cone foundation is formed by inserting the grout or concrete in the form of cones and columns in advance. This prevents the occurrence of loosening or displacement of the adjacent ground or structure due to excavation, eliminating the process of excavation and backfilling, thereby providing an economical and easy-to-install foundation and its construction method.

More specifically, in the case of pile foundations, it is difficult to increase the tip bearing capacity because the foundation cross-section is small, and consequently, a large number of pile foundations have to be installed. Although grout is being carried out to secure the effect, it is not only easy to secure accurate tip bearing capacity but also the number of piles can be significantly reduced by installing a foundation having a pre-calculated cross section in a state of doubt about its effect. The economic effect is great, and the installation method is simple, so that the bearing capacity of the pile foundation can be secured easily.

FIG. 1 is a schematic diagram of a general enlargement foundation, FIG. 1A is a rectangular enlargement foundation, FIG. 1B is a circular enlargement foundation, and FIG. 2 is a schematic view of a general pile foundation. ) Is a perspective view of constructing a pile made of steel or reinforced concrete in advance, Figure 2 (B) is the construction of the site pile to be installed in the site by placing concrete in the excavation after excavation to a predetermined depth It is a cross section.

On the other hand, Figure 3 is a perspective view of the extended tip support base of the present invention applied to the enlarged base, Figure 3 (A) shows the shape of the cone and the cylinder coupled, Figure 3 (B) is a cone-shaped enlarged tip support The basics are shown.

4 is a perspective view of the expanded tip support base of the present invention applied to a pile foundation, and FIGS. 5 to 7 are schematic views of a grout hose 500 for grouting the expanded tip support base of FIGS. 3 and 4. to be.

In addition, Figures 8 to 10 is a view of an embodiment showing an example of another extended tip support base of the present invention, Figure 11 is a cross-sectional view of a number of foundations of the present invention, Figure 12 (A) is a soft ground Example applied to the retaining wall structure installed on the top, FIG. 12 (B) shows a basic embodiment of the pipeline embedded on the soft ground.

13 and 14 are flowcharts showing an example of the extended tip support base construction of the present invention.

FIG. 15 is a schematic view showing an example in which an extended tip support base of the present invention is constructed as a group pile, and FIG. 16 is a schematic view showing an example in which a plurality of columns are installed in one cone base in the present invention.

As shown in Figures 3 to 4, the extended tip support base using the cone foundation of the present invention, the pillar 100 is inserted into the ground; Cone base 300 is installed in the lower portion of the pillar 100, the upper portion has a diameter larger than the diameter of the pillar 100, and formed in a cone shape gradually decreases in diameter as it goes down; It is composed of a grout material or concrete that is filled in the pillar 100 and the inside of the cone base 300.

In this case, the pillar 100 itself is formed in a state in which the grout or concrete is cured as shown in FIG. 9, and may not be provided with steel or FRP pipes.

In this case, it is possible to proceed only when the ground is relatively soft and there is little breakage of the grout or concrete column during the excavation process.

In addition, as shown in FIG. 10, the lower cone foundation 300 may also be composed only of cured grout material or concrete.

In this case, the ground is much softer than when only the pillar 100 is formed of grout material or concrete, or may be applied only when an additive for increasing strength is added to the grout material or concrete.

In addition, the pillar 100 is not limited to being installed only in one cone foundation 300, a plurality of pillars 100 may be installed in one cone foundation 300 as shown in FIG. will be.

This, because the cone foundation 300 when the cone foundation 300 is installed, it is possible to install a plurality of pillars (100).

The extended tip support base of the present invention having the above configuration shows the effect of increasing the supporting force by expanding the foundation cross-sectional area for the purpose of increasing the tip bearing capacity of the enlarged foundation and the pile foundation through the soft ground.

As shown in Figures 3 and 4 when the column 100 or the pile tip cross-sectional area is enlarged, the tip bearing capacity is increased. To see this, first, the general allowable bearing capacity per unit area for the enlarged foundation of the direct foundation is shown.

In general, if the foundation is located on the high quality ground, the allowable bearing capacity increases in proportion to the size of the foundation width B. Therefore, the larger the width B is, the more favorable it is. The larger the cross-sectional area A, the smaller the working pressure q per unit area. As a result, the relationship between the allowable bearing force per unit area and the working pressure must satisfy the condition q _a > q. It is.

Meanwhile, in the case of pile foundations, the ultimate bearing capacity Qu is the sum of the tip bearing force Qp and the friction bearing force Qs, and the allowable bearing force Qa is obtained by dividing the ultimate bearing force Qu by the safety factor Fs.

The tip bearing force Qp = qu · Ap is the product of the tip bearing force qu per unit area and the tip area Ap, so that the pile bearing capacity increases as the tip area Ap of the pile increases.

In such a configuration, the pillar 100 formed in the shape of a pipe in FIGS. 3 and 4 is connected to the deformation prevention member 200 having a-or + shape installed inside the cone foundation 300 that becomes the tip foundation. It can be seen that it is configured to perform the grout through the inside, in which the hole 210 in which the grout flows out is preferably installed in the up and down and side directions on the end side of the -shaped or + shaped deformation preventing member 200. .

As a result of the above examination, the upper diameter of the cone base 300 is most preferably formed to be 2 to 5 times larger than the diameter of the pillar 100 so as to secure a sufficient cross section.

If described in detail through the flow chart of Figure 13 and 14 attached to the extended tip support base construction method using the cone foundation of the present invention configured as described above are as follows.

The embodiment of Figure 13,

After arranging the foundation installation ground first, select the foundation installation position.

Ground clearance and selection of foundation installation locations follow a variety of known methods.

Then, the cone base 300 as described above, that is, a pillar 100 having a hollow inside is installed at the upper portion, the upper portion has a diameter larger than the diameter of the pillar 100 and the cone shape gradually decreases in diameter as it goes downward. The cone foundation 300, which is formed in the center and has a receiving portion therein, is positioned at an installation position and then drilled to a predetermined depth by using rotation and indentation by self-poring.

After drilling, the grout material or concrete is injected and cured in the interior of the pillar 100 and the cone base 300 to complete the construction of the expanded tip support base of the present invention.

At this time, while rotating the cone base 300 in the grout step to repeat the rise and fall to perform the grout while relaxing the ground to fill the grout material or concrete in the upper part of the cone base 300 to complete the foundation, Figure 4 and As the mixing stir 400 is further formed by mixing and stirring the grout material or concrete and soil, the mixing stir 400 is formed in this way to increase the contact area of the soil between the foundation and the ground to form a more solid foundation can do.

As described above, when the cone foundation 300 repeatedly raises and falls, the receiving portion inside the cone foundation 300 becomes an empty space, and the ground above the cone foundation 300 partially collapses into the cone foundation 300. Therefore, the grout material or concrete will penetrate into the relaxed soil of the receiving portion and the cone base 300 while relaxing the ground easily.

In this configuration, the cone base 300 is made of any one material of steel or reinforced plastic, and the deformation preventing member 200 is installed therein so that it is not deformed or destroyed in the process of being inserted through rotation and indentation. In addition, the deformation preventing member 200 is empty inside, and is formed in a cylindrical shape with a hole 210 formed on the outer circumferential surface thereof so that grout material or concrete can be moved or filled to the inside of the deformation preventing member 200. something to do.

In addition, the deformation preventing member 200 is formed so that one side is fixed to the pillar 100, and the other side is fixed to one side of the cone foundation 300, so that the pillar 100 and the cone foundation 300 are integrated as a result. It would be preferable.

In this configuration, the method of injecting grout material or concrete may be applied to the method of injecting into the column 100, using the grout hose 500, and the grout hose to uniformly fill the grout material or concrete from the bottom. It is preferred to use 500.

In an embodiment using the grout hose 500 is installed to be connected to the side of the pillar 100 and the upper side of the deformation preventing member 200, as shown in Figures 5 and 6, connected to the deformation preventing member 200 By installing the hose hole 510 in the part, the grout material or concrete is supplied through the hose hole 510 can be configured to perform the grout from the bottom gradually.

As another example, as shown in FIG. 7, the grout hose 500 is installed inside the pillar 100 and the deformation preventing member 200, and the grout material or concrete is formed through the hole 210 of the deformation preventing member 200. It may be configured to be supplied and grouted gradually from below.

That is, in the case of the pillar 100 having an empty shape, the grout hose 500 may be installed in the pillar 100 or the pillar 100 may be used as a grout passage, and the grout may be disposed on the side of the pillar 100. Bonding the hose 500 for and the inside of the cone foundation 300 is installed in the form of-or + -shaped deformation preventing member 200 to the pipe directly connected to the deformation preventing member 200, and The grout hose 500 is extended to bind with the deformation prevention member 200 of the + type to grout the inside of the cone foundation 300 and the upper cone foundation 300 through the hose hole 510 for draining the grout. Apply or insert the grout hose 500 into the pillar 100, the grout hose 500 is inserted into the deformation preventing member 200 through the hole 210 and the hose hole 510 300 may be configured to grout the top.

On the other hand, as shown in Figure 14 as another construction method of the present invention,

After arranging the foundation installation ground, select the foundation installation position,

Rod-shaped pillars 100 are installed on the upper portion, and the upper portion has a diameter larger than the diameter of the pillars 100 and is formed in a cone shape gradually decreasing in diameter as it goes down, and formed by curing the grout material or concrete ( After preparing 300)

The prepared cone foundation 300 may be configured to perforate to a predetermined depth through rotation or indentation.

Such a construction is relatively simple in construction compared to the wet construction method described above as a dry construction method.

In addition, the pillar 100 and the cone base 300 as shown in Figure 9 or 10 has the advantage that can be formed only of grout material or concrete without a separate case.

However, such a structure will be possible when the ground is soft as described above when the pillar 100 consisting of grout material or concrete, cone foundation 300 is not damaged enough.

In consideration of this point, in the construction method as described above, it is possible to install a cylindrical pipe on the outside of the column 100, or a case of steel or synthetic resin material on the outside of the cone base (300).

The extended tip support base and construction method using the cone foundation of the present invention as described above may be selectively applied to the dry and wet methods described above according to the condition of the ground and the degree of ease of construction. In order to form, it will be most preferable to apply the above-described wet construction method and foundation.

On the other hand, Figure 11 is an embodiment of the pile foundation is a perspective view of the foundation slab is installed on the upper part after the expanded tip support pile foundation of the present invention.

12 is a cross-sectional view showing the foundation of the retaining wall and the irrigation canal installed in the soft ground according to the present invention shows a state that is constructed on a solid ground through the soft ground.

In addition, Figure 15 is another example of the application of the extended tip support base of the present invention, in general, the pile pile is not less than three times the diameter of the pile tip surface (Group Pile) effect does not appear, the general pillar Although the cross section is relatively small, it is difficult to see the group pile effect, but in the case of the extended tip support base of the present invention, the diameter of the cone base surface is enlarged 2 to 5 times larger than the column diameter, so that the group pile effect can be easily seen.

In this case, the overall bearing capacity is obtained by multiplying the number of piles by the bearing capacity of a single pile, and it is assumed that a large expansion base of B × L is installed. .

As such, the extended tip support base and construction method of the present invention may be applied and used as a basis of various structures.

In addition, in the case of a nearby structure or a place where ground loosening is a problem, it was difficult to install the expansion foundation by the conventional method, it can be easily installed expansion foundation without the work of ground excavation or backfilling, pile In the case of foundations, the tip area that meets the solid ground increases the tip bearing capacity of the piles, thereby reducing the number of pile foundations installed by the existing method, which enables economic construction, as well as securing structural strength. Therefore, it will be possible to secure the bearing capacity more reliably in the design.

The expanded tip support base and its construction method using the cone foundation of the present invention will be easily applied to small diameter pile or slope activity restraint method, and restraint method for stabilizing soft ground.

1 is a schematic diagram of a conventional enlarged basis.

(A): Schematic of square enlargement basis.

(B): Schematic diagram of the circular enlargement basis.

Figure 2 is a schematic cross-sectional view showing a state of a conventional pile foundation.

(A): Cross-sectional schematic which shows the cross section of the pile foundation of a ready-made product.

(B): Schematic diagram showing a cross section of a field-pound pile foundation.

Figure 3 is a perspective view showing an example of the extended tip support base of the present invention applied to the direct foundation.

(A): The perspective view which showed the cross section of the shape of the expanded cross section combining the cone and the cylinder.

(B): A perspective view in which the enlarged cross-sectional shape shows a cone-shaped cross section.

Figure 4 is a perspective view showing an example of the extended tip support base applied to the pile foundation of the present invention.

(A): The perspective view which showed the cross section of the shape of the expanded cross section combining the cone and the cylinder.

(B): A perspective view in which the enlarged cross-sectional shape shows a cone-shaped cross section.

5 to 7 are perspective views in which the grout hose is disposed in the extended tip support base of the present invention.

8 to 10 is a perspective view showing an example of the extended tip support base that is constructed dry in the present invention.

Figure 11 is a schematic view of an example installed through the soft ground as a retaining wall and irrigation channel foundation of the present invention.

12 is a cross-sectional view showing the foundation of the retaining wall and irrigation canal installed in the soft ground according to the present invention

Figure 13 and Figure 14 is a construction sequence diagram showing the construction sequence of the extended tip support base of the present invention.

15 is a schematic view showing an example in which the extended tip support base of the present invention was constructed in the form of a group pile.

16 is a schematic view showing a state in which a plurality of pillars are installed in one cone foundation in the present invention.

<Detailed Description of Major Symbols in Drawing>

100: pillar 200: deformation preventing member

210: hole 300: cone foundation

400: mixed stirring part 500: hose

510: hosehole

Claims (10)

In the extended tip support base construction method, A position selection step of selecting a foundation installation position after arranging foundation installation grounds; A pillar 100 having a hollow shape is installed at an upper portion thereof, and a cone foundation having a diameter larger than the diameter of the pillar 100 and formed in a cone shape gradually decreasing toward the lower portion thereof and having a receiving portion therein ( A drilling step of drilling to a predetermined depth by using the rotation and indentation of the foundation by self-punching after positioning the 300); And a grout step of injecting grout material or concrete into the interior of the column and the receiving portion of the cone foundation 300 after reaching the predetermined depth. Extended tip support base construction method using cone foundation. The method of claim 1, The grout step (S300) by rotating the cone base 300 while repeating the rise and fall to perform the grout while relaxing the ground characterized in that to fill the grout material or concrete in the upper part of the cone base 300 to complete the foundation doing, Extended tip support base construction method using cone foundation. The method of claim 1, The upper portion of the cone foundation 300 is characterized in that the diameter of 2 to 5 times larger than the pillar 100, Extended tip support base construction method using cone foundation. The method of claim 1, The cone base 300 is made of any one material of steel or reinforced plastics, and the deformation preventing member 200 is installed therein so that it is not deformed or destroyed in the process of being inserted through rotation and indentation, Deformation preventing member 200 is hollow inside, characterized in that formed in a cylindrical shape formed with a hole 210 on the outer peripheral surface, Extended tip support base construction method using cone foundation. In the extended tip support base, Constructed by the construction method of any one of claims 1 to 4, A rod-shaped pillar 100 inserted in the ground; Cone base 300 is installed in the lower portion of the pillar 100, the upper portion has a diameter larger than the diameter of the pillar 100, and is formed in a cone shape gradually decreases in diameter as it goes down; Consists of grout material or concrete that is filled in the pillar 100 and inside the cone foundation 300, Extended tip support base using cone foundation. In the extended tip support base construction method, A position selection step of selecting a foundation installation position after arranging foundation installation grounds; Rod-shaped pillars 100 are installed on the upper portion, and the upper portion has a diameter larger than the diameter of the pillars 100 and is formed in a cone shape gradually decreasing in diameter as it goes down, and formed by curing the grout material or concrete ( Preparing step 300); Comprising a step of drilling the prepared cone base 300 to a predetermined depth through rotation or indentation, comprising, Extended tip support base construction method using cone foundation. The method of claim 6, Characterized in that the cylindrical pipe is installed on the outside of the pillar 100, Extended tip support base construction method using cone foundation. The method according to any one of claims 6 to 7, Characterized in that the case of steel or synthetic resin material is installed outside the cone base 300, Extended tip support base construction method using cone foundation. The method according to any one of claims 6 to 7, The upper portion of the cone foundation 300 is characterized in that the diameter of 2 to 5 times larger than the pillar 100, Extended tip support base construction method using cone foundation. In the extended tip support base, It is constructed by the construction method of any one of claims 6 to 7, A rod-shaped pillar 100 inserted in the ground; Cone base 300 is installed in the lower portion of the pillar 100, the upper portion has a diameter larger than the diameter of the pillar 100, and is formed in the shape of a cone gradually decreases in diameter as it goes to the bottom, and the cured grout; Configured, including Extended tip support base using cone foundation.

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