JP7597413B2 - Method of fixing the support posts and driving the piles - Google Patents

Description

The present invention relates to techniques that simplify the work required to install and remove posts and piles and/or improve the accuracy as to the location and orientation of the piles when they are driven into the ground .

Columns fixed to the ground may be used to support a structure at an elevated (high or low) point above ground.

Here, in one example, "high place" means a place that is 2m or more above the foundation surface (e.g., the ground surface, the scaffolding on the ground that is the earth's surface), while "low place" means a place that is lower than that high place.

The above-mentioned "support pillars" are also called poles or posts, and are made of, for example, round or square pipes made of steel or plastic. Support pillars may be delivered to the site as prefabricated products, or they may be constructed on site.

The above-mentioned "structures" include, for example, structures that display information, such as signs (e.g., display boards for commercial advertising), guide boards or signs (e.g., traffic signs, traffic signals, etc.) (see, for example, Patent Documents 1 and 3), and enclosures such as protective fences and temporary enclosures (see, for example, Patent Documents 2 and 4).

Furthermore, the term "structure" includes structures that are installed outdoors and exposed to wind, rain, and snow (e.g. outdoor signs) and structures that are installed indoors.

In addition, there are several types of support for a "structure" by pillars, including a type supported by one pillar (single-legged type) and a type supported by multiple pillars extending parallel to each other (multi-legged type). A multi-legged type has the advantage of having higher torsional rigidity around the vertical axis than a single-legged type, and also the advantage that even if an abnormality occurs in one of the pillars, as long as the other pillars are normal, the pillars can be prevented from tilting or falling over.

The precast pile method is a construction method for fixing piles to the ground. The precast pile method involves driving precast piles (e.g., steel or concrete, solid or hollow structure) into the ground.

There are two prefabricated pile methods: the driving pile method and the embedded pile method.

The driving pile method involves driving prefabricated piles (e.g., steel or concrete) into the ground using the striking force of a hammer, without having to dig pilot holes in the soil beforehand.

Here, "hammer" refers to a manual hammer, a pile driver (e.g., a pneumatic hammer) that is a construction machine (automatic hammer). A manual hammer is a large hammer with a metal lump attached to the end of a long handle that is held by the worker and is used by swinging it down, or it can be held up by the worker's hand against gravity and then allowed to fall freely to strike a pile.

In contrast, the buried pile method involves excavating the ground to a specified depth to create a pilot hole, and then inserting a prefabricated pile into the hole. One such buried pile method is known as the root wrapping method (see, for example, Patent Document 3). This root wrapping method is a method in which, for example, an enlarged concrete bulb is created at the bottom end of the pile.

According to this method, a pilot hole is first excavated in the ground, and crushed stone is poured into the bottom of the hole and tamped down. A post is then inserted into the hole, and temporary braces are used to keep the post upright so that it does not tip over. Ready-mixed concrete is then poured into the hole so that it surrounds the post. The ready-mixed concrete is then allowed to harden, thereby fixing the post in place.

By using this root wrapping method, there is no need to replace the pillars during the long lifespan of a concrete foundation, which is usually 20-30 years.

However, this method requires steps such as digging the ground to create pilot holes, temporarily supporting the posts, and constructing concrete foundations, which increases costs and extends the construction period. Therefore, this method is not suitable for cases where the posts and piles are used for a short period of time and therefore need to be removed frequently.

Patent Document 1 discloses a technique for driving a pile into the ground and using the driven pile to fix a support pillar. However, this document only discloses using the pile to press the support pillar against the ground surface (ground level) after it has been installed, and does not disclose connecting the pile to the support pillar after it has been driven into the ground, or connecting the pile to the support pillar coaxially. Furthermore, this document does not disclose driving the pile into the ground while guiding it so that it can move up and down.

Patent Document 2 discloses a technique for repeatedly applying impact forces to a pile to drive the pile deeper into the ground in stages. However, this document only discloses that after driving the pile into the ground, a pilot hole is excavated in the ground by pulling it out, and a support is inserted into the pilot hole, but does not disclose that the pile driven into the ground is left in place and the upper end of the left pile is connected to the lower end of the support.

Furthermore, like Patent Document 1, this document does not disclose driving a pile straight into the ground using a pile guide that guides the pile itself so that it can move up and down. Specifically, this document discloses driving piles using a tool called a guide rod, but more precisely, the guide rod is used to guide the air hammer so that it can slide up and down, and is not used to guide the pile itself so that it can slide up and down.

Patent Document 3 is primarily concerned with the aforementioned root wrapping method, and is silent on the driving pile method. This document discloses that if a vertical hole is excavated in the ground at an unplanned incline, the pile will also be erected in the hole at an incline accordingly, resulting in a decrease in the verticality of the support inserted into the pile. Furthermore, this document discloses that after the pile is wrapped in concrete in the ground, it is coaxially connected to the support. However, this document does not disclose the use of a pile fixed in the ground directly to fix the support, nor the connection of a pile fixed in the ground and a support in a state of mutual contact.

Patent Document 4 discloses a technique for driving piles into the ground. Furthermore, this document discloses driving the pile into the ground while guiding the pile itself so that it can move up and down. However, this document does not disclose connecting the pile to a support after it has been driven into the ground, connecting the pile to the support coaxially, or connecting the pile to the support in a state where the piles are in contact with each other.

Patent Document 5 discloses a buried pile method as a pile construction method, but is silent about a driven pile method. Furthermore, this document does not disclose that the support pillar is divided into a part that exists above ground and a part that exists underground and acts as a foundation, and that the latter part is treated as a pile.

Furthermore, this document points out that one drawback of using the buried pile method is that if a large wind pressure acts on a structure supported above ground by the upper end of a pillar whose lower end is buried in the ground, the strength of the pillar may become unstable.

Furthermore, this document points out that the cast-in-place pile method, in which a pilot hole is first excavated in the ground to create a pilot hole, then a cylindrical rebar assembled on-site is dropped into the pilot hole, and then fresh concrete is poured into the hole and the concrete is allowed to harden to create the pile, does indeed provide greater strength and stability than the buried pile method, but it also has problems such as the great effort (man-hours, construction time, etc.) and cost required to remove the posts.

Japanese Utility Model Application Publication No. 58-21177 Japanese Unexamined Patent Publication No. 7-189529 JP 2004-190241 A Japanese Patent Application Publication No. 10-37194 JP 2014-001542 A

As such, there are a variety of pile construction methods, each with its own advantages and disadvantages. For this reason, it is necessary to select from among these pile construction methods the one that is most appropriate for the site (e.g., topography, soil quality, natural phenomena, etc.) and use (e.g., average period of use, etc.) taking into account various factors related to the site and use, and there are various factors that must be taken into consideration when selecting a method. These factors include, for example, the size of the pillars, the average number of years they will be used, factors related to the construction period for installing and removing the pillars, and factors related to the construction costs for installing and removing the pillars.

The support pillars are required to meet certain strength requirements in order to fulfill their mission of stably supporting the structure they support in the air in the environment of the installation site (e.g. wind pressure, rain, snow accumulation, vibration, etc.).

The strength requirements imposed on a support are determined by the weight and size (particularly the height dimension of the support) of the support and the structure it supports. Also, in general, given the structural environment in which the structure is held in a position above ground level, the weight ranking of the structure depends on the ranking of the height dimension of the structure (i.e., generally equivalent to the length (height dimension above ground level) of the support that supports the structure).

Furthermore, the strength requirements imposed on the supports also depend on the average number of years that the structure will be used at the same site. Therefore, if a higher strength requirement is imposed on a support than would be appropriate for a structure with a short average number of years of use, the support will be over-qualified in terms of strength, leading to waste.

Therefore, for ease of explanation, the types of pillars are classified into three types according to the length of the pillar. Specifically, the types of pillars are classified into small pillars with a length of less than 2m, medium pillars with a length of 2m to less than 4m, and large pillars with a length of 4m or more.

Specifically, small poles include, for example, signs that are installed for a short period of time in vacant lots, while medium-sized poles include, for example, outdoor signs installed in parking lots (including bicycle parking lots), as illustrated in Figure 1, as well as pedestrian traffic lights and road signs, and large poles include, for example, traffic lights for vehicles (e.g., 4.5 m or more).

If the support is large, it is subject to high strength requirements, if it is medium, it is subject to medium strength requirements, and if it is small, it is subject to low strength requirements.

Typically, to meet high strength requirements, the piles supporting the columns are anchored to the ground using the aforementioned concrete foundation and filler by the root wrapping method. Also, typically, to meet low strength requirements, the piles supporting the columns are anchored to the ground by simply driving them into the ground using a simple driven pile method, without using concrete foundation or filler.

To date, there has been no pile construction method suitable for achieving intermediate strength levels between those achieved by the root wrapping method and those achieved by the simple driving pile method.

In response to this, the inventor conducted research and development into a pile construction method suitable for achieving an intermediate strength level. In doing so, the inventor envisioned a structure such as the above-mentioned outdoor parking sign used by a company that temporarily manages land on behalf of the landowner as a parking lot, which may suddenly need to be removed and whose length of continuous use is unstable, and selected the following requirements.

(1) Average years of use

Based on past statistics regarding the use of the above-mentioned outdoor parking lot signs, the inventors have set the maximum usage period of the posts at about 5 years. Therefore, if the root wrapping method were used, the strength level achieved by this method (for example, a service life of about 20-30 years) would be excessive.

The inventors therefore researched and developed a new pile construction method suitable for achieving a lean strength level in the pillars in relation to the maximum service life of the pillars.

(2) Bending strength

In general, pillars must be safe and reliable enough that they will not tilt or collapse, even if the ground is weak or there is strong wind. In other words, it is necessary to ensure the necessary degree of ground compaction and the bending rigidity of the pillars (deflection characteristics due to wind loads as lateral loads). For this reason, the level of strength achieved by simply driving piles into the ground is insufficient.

Furthermore, when using pillars fixed to the ground, it is important to take care that the pillars do not tilt or collapse due to bending moments generated in the pillars by wind pressure acting on the structure when the structure is in use.

The bending moment acting on the support due to the wind pressure is known to be maximized near the ground surface (for example, in the bending mode of a quasi-cantilever beam, which is a structure that can be approximated in terms of material mechanics (if the ground can be assumed to be completely rigid (the ground reaction force is maximum), it can be approximated as a cantilever beam), at the position where the bending start point of the quasi-cantilever beam (the fixed end in the case of a cantilever beam) appears).

In addition, when adopting a structure in which the pillars are not fixed directly to the ground but are indirectly fixed to the ground by connecting them to piles fixed to the ground, it is necessary to connect the multiple individual parts, namely the pillars and piles, to each other.

The connection between the pillar and the pile is usually placed on the ground surface, i.e., at the position on the pillar where the external bending moment is maximized. Therefore, the inventors recognized that the type of structure adopted for the connection is an important factor that determines the resistance of the pillar to the bending moment. The maximum bending moment increases the longer the pillar is.

The inventor therefore devised a structure connecting the pile and the support that prevents a sudden change in the section modulus between the two members, thereby reducing stress concentration at the connection between the two members.

(3) Accuracy of the orientation (position and angle) of piles fixed into the ground

The verticality of a pile fixed to the ground refers to the angle at which the center line of the pile fixed to the ground inclines relative to the direction in which gravity acts, i.e., the vertical direction; in other words, the angle at which the center line of the pile deviates from the vertical direction. The closer the verticality of the pile is to 0, the closer the center line of the pile is to the direction of gravity.

When a structure is supported by pillars, the structure is generally placed at or near the head of the pillar. Therefore, if the pillar is installed at an angle from the vertical, the weight of the structure acts on the pillar as an eccentric load at all times, resulting in a bending moment acting on the pillar. This bending moment constantly applies a load to the pillar and, in some cases, can be a cause of fatigue failure of the pillar, so it should be reduced or eliminated.

On the other hand, when a support pillar is connected to a pile fixed to the ground, i.e., when the apparent support pillar (when the support pillar and the pile are viewed as one support pillar) adopts a two-part structure, the verticality of the support pillar depends on the verticality of the pile. Therefore, the inventor recognized that fixing the pile to the ground in a state where its verticality is good is essential to improve the verticality of the support pillar.

Therefore, the inventors have devised a method to improve the verticality of piles fixed to the ground regardless of the number of pillars supporting a single structure, thereby improving the verticality of the pillars connected to those piles, and ultimately preventing unexpected bending moments from occurring at the pillars, particularly at the bending start points of the pillars.

In addition, when a structure is supported by multiple parallel columns that are connected to multiple piles, during the work of fixing the multiple piles to the ground, it is necessary to improve the accuracy of the pile spacing, improve the verticality of each pile, and ultimately improve the parallelism of the multiple piles.

The reason for this will be specifically explained below using the example of a case where, after the assembly of a signboard is complete, its multiple posts are attached to multiple piles fixed to the ground, i.e., multiple piles whose relative positions are fixed (constrained to each other) are attached to multiple posts whose relative positions are fixed (constrained to each other).

In this case, if a connection structure is adopted in which the multiple posts are coaxially connected to the multiple piles (for example, a structure in which one member is inserted into a hollow hole in the other member), it will be impossible to assemble the multiple posts, i.e., for example, a signboard, to the multiple piles, unless the post and the pile to be connected to each other are arranged in a straight line so that they match in both position and orientation.

More specifically, when multiple piles are fixed into the ground, if there is an error in the pile spacing and/or pile verticality, the top end of the part of the pile that protrudes from the ground surface (i.e., the part of the pile that should be connected to the bottom end of the support) will shift laterally from the target position. In this case, the position error of the connection point of the pile to the ground tends to appear at the top end of the part of the pile that protrudes from the ground surface, amplified according to the error Δθ in the verticality of the pile and the length L of the part of the pile that protrudes from the ground surface.

Therefore, if multiple pillars are forcibly attached to multiple piles, they will be twisted together, causing unexpected residual stress in each structural member. In particular, if this residual stress is tensile stress, it can cause cracks to form in each structural member.

The inventor therefore devised a method to reduce errors in the position and orientation of the piles fixed to the ground when multiple pillars support a single structure, thereby making it possible to effortlessly assemble multiple pillars to multiple piles.

When posts are fixed to the ground using the aforementioned root wrapping method, a single continuous post exists that spans both the ground and the air, so it is assumed that there is no risk of orientation errors in multiple posts fixed to the ground causing problems when assembling the posts, or that even if there are any, they will be minimal.

In particular, as described below, if a pair of posts are inserted into their respective pilot holes with their relative positions fixed (for example, when the signboard's assembly is complete) and before their respective concrete foundations harden, the geometric error between the pair of posts will not pose any new serious problems.

(4) Construction period and costs

As mentioned above, the maximum period of use for pillars in the category that the inventors are interested in is short. Therefore, if the construction period for installing and removing the pillars is long, and the construction costs increase, the net profit obtained from the use of the pillars will decrease. As a result, in some cases, the construction costs will squeeze the net profit, and the business related to the pillars may go bankrupt.

Therefore, in order to shorten the construction time required to install and remove the pillars, the inventors have devised a method that allows workers to install and remove the pillars as simple manual work using simple tools instead of heavy machinery.

According to the inventor's experience to date, the aforementioned root wrapping method is expected to enable the strength of the posts to be managed without worry. However, with this root wrapping method, the installation of the posts requires the bringing in and taking out of heavy machinery, the use of that machinery to excavate the ground to create pilot holes, temporary support for the posts, and the construction of a concrete foundation. As a result, the removal of the posts also requires the bringing in and taking out of heavy machinery, the use of that machinery to excavate the ground, and the use of that machinery to remove the concrete foundation. As a result, the construction period tends to be extended and construction costs to increase.

As a result, this root wrapping method was not suitable for the pillars that the inventors were currently focusing on, both in terms of construction time and costs.

In short, the inventor has researched and developed a method of fixing supports that allows workers to easily and quickly install and remove them manually, without sacrificing the strength that has been achieved so far for medium-sized supports.

However, the pillar fixing method that is the result of this research and development can be applied not only to medium-sized pillars, but also to small and large pillars. Furthermore, the pillar fixing method that is the result of this research and development can be applied when fixing a pillar to soft ground, and can also be applied when fixing a pillar to hard ground (e.g., hard ground, good ground, solid ground, dense solid ground).

Against the background described above, the present invention aims to provide a technique that simplifies the work required for installing and removing posts and piles and/or improves the accuracy of the position and orientation of the piles when they are driven into the ground.

In order to solve the problem, according to one aspect of the present invention, a method for fixing at least one support pillar to the ground by using at least one steel pile , which is made of steel and is configured to have no nodes at least at its axial center portion, as a foundation, instead of using a concrete foundation, comprising the steps of:
a pile driving process in which a vertical hole is created in the ground by driving the pile into the original ground where a pilot hole has not been excavated in advance, and then the pile is pulled out and sand is poured into the vertical hole as a filler without adding cement, and then the sand poured into the vertical hole and the surrounding soil are compacted while being gradually pushed outward by driving the pile, and when compaction is completed, the pile is left in the ground with its upper end protruding from the ground surface, thereby fixing the pile to the ground;
and a post connecting step of connecting the support to the pile using a portion of the pile fixed to the ground that protrudes above the ground surface after the pile is fixed to the ground.
According to another aspect of the present invention, there is provided a method for driving a steel pile into ground, the pile being configured to have no nodes at least at a central axial portion of the pile , the method comprising the steps of:
This provides a pile driving method in which a vertical hole is created in the ground by striking and driving the pile into the original ground where a pilot hole has not been excavated in advance, and then the pile is pulled out and sand is poured into the vertical hole that appears as a filler without the addition of cement, and then the sand poured into the vertical hole and the surrounding soil are compacted while being gradually pushed outward by driving the pile, and when compaction is complete, the pile is left in the ground, thereby fixing the pile to the ground.

The present invention provides the following aspects. Each aspect is divided into clauses, each clause is numbered, and the numbers of other clauses are cited as necessary. This is to facilitate understanding of some of the technical features that the present invention may employ and their combinations, and should not be construed as limiting the technical features and combinations that the present invention may employ to the following aspects. In other words, it should be construed that there is no prohibition on appropriately extracting and employing technical features that are not described in the following aspects but are described in this specification as technical features of the present invention.

Furthermore, describing each paragraph in a form that refers to the number of other paragraphs does not necessarily mean that it is prohibited to separate and make independent the technical features described in each paragraph from the technical features described in other paragraphs, and it should be interpreted that it is possible to make independent the technical features described in each paragraph as appropriate depending on their nature.

(1) A method in which, instead of using a concrete foundation, an operator manually drives at least one pile into the ground and uses the pile as a foundation to fix at least one support to the ground, comprising the steps of:
a pile driving process in which the pile is repeatedly driven into and pulled out of the ground, and after each pullout, sand is poured into a vertical hole created in the ground as a filler, and the same pile is then repeatedly driven into the ground each time, gradually expanding and compacting the sand and surrounding soil that have been poured into the vertical hole, and when compaction is complete, the pile is left in the ground with its upper end protruding from the ground surface, thereby fixing the pile to the ground;
and a post connecting step of connecting the support to the pile coaxially and in contact with each other using a part of the pile fixed to the ground that protrudes above the ground surface after the pile is fixed to the ground.

(2) Furthermore,
The post fixing method described in (1) includes a guide installation step in which, prior to the first driving, an operator installs a pile guide device that guides the pile so that it can move up and down while in contact with its outer circumferential surface, and a pile positioning device that positions the pile horizontally on the ground surface and has a through hole for the pile to pass through.

(3) The pile guide device includes a guide pipe into which the pile is fitted so as to be slidable in the axial direction,
The method for fixing a post according to claim 2, wherein the guide installation step includes a step of installing the pile guide device relative to the pile positioning device so that the guide pipe passes through the through hole.

(4) The method for fixing a post according to (2) or (3), wherein the guide installation step includes a step in which, after the pile positioning device is installed on or near the ground surface, an operator positions the pile guide device using the through hole of the installed pile positioning device as a visual target.

(5) The pile guide device is
A guide pipe into which the pile is fitted so as to be axially slidable;
and a direction adjustment mechanism for adjusting the direction of the guide pipe;
The method for fixing a support pillar described in any one of items (2) to (4), wherein the guide installation process includes a process in which an operator uses the orientation adjustment mechanism to adjust the orientation of the pile guide device so that the guide pipe extends vertically.

(6) Furthermore,
Prior to the pillar connecting step, a guide removal step is included in which an operator removes the pile guide tool from the ground surface while leaving the pile positioning tool on the ground surface,
The pillar connecting process includes, after the pile guide device is removed from the ground surface, (a) a process in which an operator coaxially covers a reinforcing sleeve on the portion of the pile protruding from the ground surface, and (b) a process in which an operator further coaxially covers the hollow hole of the lower end of the pillar on the reinforcing sleeve, thereby connecting the pile and the pillar to each other in a triple-cylinder structure via the reinforcing sleeve.The pillar fixing method described in (3) or (5).

(7) Furthermore,
Prior to the pillar connecting step, a guide removal step is included in which an operator removes the pile guide tool from the ground surface while leaving the pile positioning tool on the ground surface,
The pillar connecting step includes, after the pile guide device is removed from the ground, (a) a step in which an operator coaxially covers the hollow hole at the lower end of the pillar over the portion of the pile protruding from the ground, thereby coaxially inserting the protruding portion into the hollow hole, and (b) a step in which the lower end is fixed, joined or fastened to the protruding portion, thereby coaxially connecting the pile and the pillar to each other in a double-tube structure. The pillar fixing method described in (3) or (5).

(8) A post fixing method according to any one of items (1) to (7), in which the at least one post is used to display information-displaying structures, including signs, guide panels, or markings, or to fix protective fences.

(11) A method for fixing at least one support pillar to the ground by manually driving at least one pile into the ground as a foundation by an operator instead of using a concrete foundation, comprising the steps of:
a driving step in which an operator manually drives the pile into the original ground without a shaft being pre-drilled by striking the pile at its upper end with a hammer, so that the upper end of the pile protrudes above the ground surface;
After the first driving is completed, a worker manually pulls out the driven pile from the ground using a pile puller, thereby creating a vertical hole in the ground;
After the first extraction is completed, an operator manually pours sand into the vertical hole as a filler.
After the first sand is poured, a worker repeats the driving step, the pulling step, and the pouring step in sequence using the same pile, thereby compacting the sand poured into the vertical hole and the surrounding soil while gradually expanding them outward; and
once the desired compaction characteristics have been achieved for the sand and surrounding soil, placing the pile in the ground with its upper end protruding above the ground surface, thereby anchoring the pile in the ground;
and a connecting step in which, after the pile is fixed to the ground, an operator connects the two by inserting the part of the pile fixed to the ground that protrudes above the ground surface into the hollow hole at the lower end of the pillar.

(12) Furthermore,
A preparation process in which, prior to the first driving, a worker manually installs a pile guide tool that guides the pile so that it can move up and down, in accordance with a target portion of the ground surface into which the lower end of the pile should start to enter;
The post fixing method according to claim 11, further comprising a removal step of manually removing the pile guide device by an operator after the pile is fixed to the ground.

(13) The linking step comprises:
After removing the pile guide tool, an operator manually inserts a portion of the pile fixed to the ground that protrudes from the ground surface into a hollow hole at the lower end of the support pillar until the end face of the lower end of the support pillar is buried in the ground;
A method for fixing a post as described in (12) above, further comprising a fastening step in which, after the insertion, an operator uses a fastener to fasten the post and the pile.

(14) The post fixing method described in any of items (11) to (13), in which the pile guide is constructed by connecting multiple pipes that cross each other at multiple levels to each other using multiple orthogonal clamps so as to form a roughly rectangular parallelepiped shape, and the multiple pipes have the same number of guide pipes as the at least one pile, and each pile is slidably inserted into each guide pipe.

(15) The method for fixing a support pole described in (14) above, in which the plurality of pipes include three or more support pipes that are erected on the ground surface in a parallel posture, and each of the support pipes has a height adjustment mechanism independent of the other, thereby adjusting the orientation of the pile guide in three dimensions to adjust the perpendicularity of the guide pipes.

(16) The at least one pile includes a plurality of piles,
The at least one support includes a number of supports equal to the number of piles;
The pile guide device is configured to guide the plurality of piles so as to be movable up and down along a plurality of center lines parallel to each other,
The method for fixing the support pole further comprises:
Prior to the first driving, a worker manually installs a pile spacing regulation tool that regulates the target pile spacing between the plurality of piles in a plan view, the pile spacing regulation tool being placed on the ground surface or at least partially buried in the ground, in accordance with the plurality of target sites on the ground surface into which the plurality of piles are to be driven;
The method for fixing a post according to any one of items (11) to (15), further comprising: an embedding step of embedding and leaving the pile spacing regulator in the ground without removing the pile spacing regulator after the post and the pile are fastened to each other.

(17) The pile interval regulation tool has a plurality of through holes through which each pile should penetrate at the same intervals as the target pile interval,
The method for fixing a post according to claim 16, wherein the preparation step includes a step in which, after the pile spacing regulation device is installed, an operator positions the pile guide device by using each through hole of the installed pile spacing regulation device as a visual target.

(18) A pile guide device according to any one of items (12) to (15).

(19) A pile spacing regulation device as described in (16).

(20) The pile interval regulation device is placed on or near the ground surface with the plurality of piles fixed to the ground,
The pile spacing regulator described in paragraph (19) acts as a tie bar that connects the plurality of piles to each other in the horizontal direction, thereby mechanically restraining the piles so that the piles are substantially prevented from moving toward or away from each other.

(31) A method for fixing at least one support to the ground by manually driving at least one pile into the ground instead of using a concrete foundation, using the pile as a foundation, comprising the steps of:
A pile driving process of driving the pile into the ground to fix the pile to the ground;
and a post connecting step of connecting the support to the pile coaxially and in contact with each other using a part of the pile fixed to the ground that protrudes above the ground surface after the pile is fixed to the ground.

(32) Furthermore,
The post fixing method described in item (31) includes a guide installation step in which, prior to driving the pile, an operator installs a pile guide device that guides the pile so that it can move up and down while in contact with its outer circumferential surface, and a pile positioning device that positions the pile horizontally on the ground surface and has a through hole for the pile to pass through.

(33) The pile guide device includes a guide pipe into which the pile is fitted so as to be slidable in the axial direction,
The method for fixing a post according to claim 32, wherein the guide installation step includes a step of installing the pile guide device relative to the pile positioning device so that the guide pipe passes through the through hole.

(34) The post fixing method described in (32) or (33), in which the guide installation step includes a step in which, after the pile positioning device is installed on or near the ground surface, an operator positions the pile guide device using the through hole of the installed pile positioning device as a visual target.

(35) The pile guide tool is
A guide pipe into which the pile is fitted so as to be axially slidable;
and a direction adjustment mechanism for adjusting the direction of the guide pipe;
The method for fixing a support pillar described in any one of items (32) to (34), wherein the guide installation process includes a process in which an operator uses the orientation adjustment mechanism to adjust the orientation of the pile guide device so that the guide pipe extends in a vertical direction.

(36) Furthermore,
Prior to the pillar connecting step, a guide removal step is included in which an operator removes the pile guide tool from the ground surface while leaving the pile positioning tool on the ground surface,
The pillar connecting step includes, after the pile guide device is removed from the ground surface, (a) a step in which an operator coaxially covers a portion of the pile protruding from the ground surface with a reinforcing sleeve, and (b) a step in which an operator further coaxially covers the hollow hole at the lower end of the pillar over the reinforcing sleeve, thereby connecting the pile and the pillar to each other in a triple-cylinder structure via the reinforcing sleeve. The pillar fixing method described in (33) or (35).

FIG. 1 is a front view showing an example of a signboard installed on a site by using a pole fixing method according to an exemplary embodiment of the present invention, together with a pole and a stake. FIG. 2 is a perspective view showing an example of how the signboard shown in FIG. 1 is installed in an area adjacent to a sidewalk on a site. FIG. 3 is a perspective view showing an example of the pile shown in FIGS. 1 and 2. FIG. FIG. 4 is a cross-sectional view showing an example of a fastener for fastening the pile shown in FIG. 2 to the support pole shown in the same figure. FIG. 5 is a perspective view showing an example of a post fixing system used by an operator to carry out the post fixing method, the system including a pile guide for vertically guiding the pile shown in FIG. 2 as it is driven into the ground, and a base plate for defining the horizontal position of the pile on the ground surface. FIG. 6(a) is a side view showing the support pipe, the main cross pipe and the guide pipe of the pile guide device shown in FIG. 5, and FIG. 6(b) is a plan view. 7 is a side cross-sectional view for explaining how the pile shown in FIG. 2 is guided vertically by the guide pipe and base plate, both of which are shown in FIG. 5, when the pile is driven into the ground. FIG. 8 is a process diagram showing an example of an installation work in which a worker installs the signboard shown in FIG. 1 as an operation in which the post fixing method is carried out. FIG. 9 is a side cross-sectional view illustrating how the base plate shown in FIG. 5 can be installed horizontally despite the inherent slope of the ground as part of the topsoil preparation step shown in FIG. 8. Figure 10 shows multiple vertical cross-sectional views for explaining in chronological order the pile driving process shown in Figure 8, in which piles are repeatedly driven into and pulled out of the ground, and after each removal, sand is poured into the vertical hole created in the ground as filler. FIG. 11 is a perspective view showing an example of a pile driving hammer used by an operator to drive a pile into the ground in the pile driving step shown in FIG. 8 . FIG. 12 is a perspective view showing an example of a pile extractor used by an operator to pull out piles from the ground in the pile driving step shown in FIG. 8 . Figure 13(a) is a side cross-sectional view for explaining the relative positional relationship between the pile, guide pipe, and base plate in the pile driving process shown in Figure 8, and Figure 13(b) is a side cross-sectional view for explaining the relative positional relationship between the pile, pillar, reinforcing sleeve, and base plate in the pillar connection process shown in Figure 8. FIG. 14 is a cross-sectional view for explaining the relative positional relationship between the pile, the post, and the reinforcing sleeve in the post connecting step shown in FIG. 8. FIG. 15 is a process diagram illustrating an example of a removal operation in which a worker removes the signboard shown in FIG. FIG. 16 is a perspective view showing an example of how a plurality of types of accessories are detachably attached to a signboard according to another exemplary embodiment of the present invention using one type of clamp. FIG. 17 is an enlarged plan view showing a clamp for detachably mounting the accessory shown in FIG. 16 to the signboard shown in the same figure, in a locked position and an unlocked position. FIG. 18(a) is a plan view conceptually showing the clamp shown in FIG. 17 together with a first adapter attached thereto, and FIG. 18(b) is a plan view conceptually showing the same clamp together with a second adapter attached thereto. FIG. 19(a) is a partial cross-sectional plan view showing the coaxial connection structure between a pile and a support pillar connected to it after driving, and FIG. 19(b) is a cross-sectional side view showing the coaxial connection structure.

Some of the more specific exemplary embodiments of the present invention will be described in detail below with reference to the drawings.

<One embodiment>

The pole fixing method according to an exemplary embodiment of the present invention is carried out by an operator using a pole fixing system 10, which will be described in detail later with reference to FIG. 5. FIG. 1 is a front view showing a signboard 20 installed on a site by carrying out this pole fixing method, together with a pair of poles 22, 22 and a pair of stakes 30, 30.

The signboard 20 is freestanding and fixed, and has a display board 40 as a structure supported by posts 22, 22 at a position above the ground surface (ground surface, ground surface, support surface, etc.).

That is, the signboard 20 is configured to include a pair of posts 22, 22 that are fixed vertically to the ground of the site (one example of an area), and a display board 40 that is supported by being sandwiched between the posts 22, 22 on both sides.

Each support 22 is made of a square pipe with a side length of 75 mm, whereas each pile 30 is made of a round bar with an outer diameter of approximately 50 mm. The round bar is, for example, solid or at least partially hollow.

The signboard 40 may be long horizontally or long vertically. In the example shown in FIG. 1, the signboard 30 is long horizontally. Specifically, the signboard 20 has a height of about 3000 to about 4000 mm and a width of about 2000 to about 3000 mm.

The signboard 20 is a double-sided display type, and therefore the display board 40 has a front (front side) display surface and a rear ( rear side ) display surface. The display surfaces on both sides can display the same or different information.

The information is expressed, for example, by letters, numbers, figures, etc. Numbers, for example, may consist of a single number or may consist of multiple digits.

Figure 2 shows an example of a signboard 20 installed in an area adjacent to a sidewalk on a site. In this example, the signboard 20 is classified as an outdoor signboard, which is installed outdoors.

Figure 3 is a perspective view of a pile 30. This pile 30 is, of course, classified as a prefabricated pile. This pile 30 is made of, for example, steel, and is made of a hollow pipe with a head (the upper end or top end when driven into the ground) 50 and a tip (the lower end or bottom end when driven into the ground) 52 closed.

The overall length of the pile 30 is about 1100 to 1600 mm, and the diameter is about 50 mm. The pile 30 has a parallel section (a section that extends straight with the same cross section) 54 in the axial center, and tapered sections 56, 58 in front and behind it.

<Outline of the coaxial insertion type connection structure between piles and supports>

As shown in FIG. 2, a corresponding support post 22 is inserted into each pile 30 driven into the ground and connected coaxially and in contact with each other. This connection structure is called a "coaxial insertion type connection structure."

This coaxial insertion type connection structure can be replaced with a connection structure in which the upper end face of each pile 30 and the lower end face of each pillar 22 are butted together and bolted together, but the coaxial insertion type connection structure shown in the figure has a larger contact surface in the axial direction for both components than the latter connection structure, and cross-sectional forces are transmitted between the two components over a wider area.

Therefore, the coaxial insertion type connection structure is more suitable for dispersing the stress generated at the connection between the pile 30 and the support 22 due to the lateral load acting on the display board 40 in the axial direction, thereby reducing stress concentration. This coaxial insertion type connection structure will be described in detail later with reference to Figure 13 (b).

Figure 4 is a cross-sectional view showing an example of a fastener 60 that fastens and fixes the pile 30 to the support 22. In the fastener 60, a U-bolt 62 is attached to the support 22 so as to partially surround the pile 30 inside the support 22, and a number of nuts 64 are screwed from the outside into the part of the U-bolt 62 that is exposed from the outer surface of the support 22. Inside the support 22, a spacer 66 is appropriately interposed between the inner surface of the support 22 and the outer surface of the pile 30.

＜Support post fixing system＞

As shown in the perspective view of FIG. 5, an operator uses a post fixing system 10 to carry out the post process method. The post fixing system 10 has a pile guide 70 for vertically guiding the pile 30 as the operator drives the pile 30 into the ground, and a base plate (anchor plate) 72 for determining the horizontal position of the pile 30 on the ground surface.

＜Pile guide tool＞

In general terms, the pile guide device 70 constitutes an example of a pile guide device that guides the pile 30 so that it can move up and down while in contact with its outer circumferential surface. In addition, the pile guide device 70 is also called the "upper guide" because it guides the portion of the pile 30 excluding the lower end portion.

Specifically, the pile guide device 70 is constructed by connecting multiple pipes that cross each other at two levels using multiple orthogonal clamps (not shown) to form a roughly rectangular parallelepiped shape. These pipes have the same number of guide pipes 80 as the number of piles 30 (two in the illustrated example). Each pile 30 is slidably fitted or inserted into each guide pipe 80. Each orthogonal clamp may be commercially available.

The plurality of pipes include three or more support pipes 90 (in the illustrated example, four support pipes are arranged at the four vertices of a rectangle) that are erected on the ground surface in a mutually parallel posture.

Each of the support pipes 90 has a height adjustment mechanism independent of the others. For one pile guide tool 70, three or more height adjustment mechanisms cooperate with each other to manually adjust the orientation (particularly, the direction) of the pile guide tool 70 three-dimensionally by an operator so that the verticality of the guide pipe 80 (the angle θ of the center line of the guide pipe 80 from the vertical direction) becomes 0 degrees.
do.

As the height adjustment mechanism, as shown in Fig. 6(a), each support pipe 90 has a jack base 92. The jack base 92 is attached to the lower end of each support pipe 90 and has a base 94 in contact with the ground, a male thread 96 inserted into the support pipe 90 , a nut 98 screwed onto the male thread 96, and a plurality of operating parts 100 extending radially outward from the nut 98.

While relative rotation between the base 94 and the male thread 96 is prevented, relative rotation and relative axial movement between the support pipes 90 and the male thread 96 are permitted. Thus, by rotating the nut 98 via the operating unit 100, the operator can raise and lower the nut 98, thereby extending and contracting the entire length of each support pipe 90.

At least one spirit level (not shown) is attached to the guide pipe 80 or to at least one other pipe whose relative positional relationship is fixed so that the worker can visually and accurately determine whether the guide pipe 80 is facing vertically.

As shown in FIG. 5, the multiple pipes further include multiple main horizontal pipes 110 and multiple sub-horizontal pipes 112. The main horizontal pipes 110 and the sub-horizontal pipes 112 intersect at right angles.

As shown in the side view of FIG. 6(a) and the plan view of FIG. 6(b), the guide pipe 80 and the support pipe 90 are erected on the ground in a position extending parallel to each other, and the main cross pipe 110 is sandwiched between the pipes 80, 90 from both sides so that it intersects with the pipes 80, 90 at right angles.

As shown in Figures 6(a) and 6(b), the guide pipe 80 is connected to the main cross pipe 110 by multiple orthogonal clamps (not shown) so as to cross at right angles, and each orthogonal clamp can be individually switched between a locked state and an unlocked state by the operator.

In the locked state, the guide pipe 80 is firmly (inseparably) fixed to the main cross pipe 110, whereas in the unlocked state, the operator can separate the guide pipe 80 from the main cross pipe 110. In other words, the guide pipe 80 is removably attached to the pile guide device 70.

＜Base plate＞

As shown in FIG. 5, the base plate 72 generally constitutes an example of a pile positioning device that positions the pile 30 on the ground surface in the horizontal direction and has a through hole 74 through which the pile 30 passes. The base plate 72 also constitutes an example of a pile spacing regulation device that regulates the target pile spacing that a pair of piles 30, 30 should be spaced apart from each other in a plan view.

The base plate 72 is also called the "lower guide" because it guides the lower end of the pile 30. The pile guide device 70 and the base plate 72 are collectively called the "upper and lower guides."

The base plate 72 further acts as a tie bar that connects the pair of piles 30, 30 to each other in the horizontal direction, thereby mechanically restraining the piles 30, 30 (e.g., holding them together from a material mechanics perspective) so that the piles 30, 30 are substantially prevented from moving toward or away from each other.

As a result, the actual pile spacing is encouraged to continuously match the target value, compared to when the base plate 72 is divided and installed discretely for each pile 30 , and the piles 22 are prevented from tilting independently at their positions on the ground surface even if the ground is soft.

Specifically, the base plate 72 is mainly made of, for example, a single steel plate 120 that extends linearly and does not deform when placed on the ground (for example, with a plate thickness of about 3 mm). The steel plate 120 has one through hole 74 at each end, for a total of two through holes 74.

In the illustrated example, the base plate 72 has, in addition to the steel plate 120, two short steel plates 122 stacked and fixed on both sides of the steel plate 120 in a direction intersecting at right angles. Each steel plate 122 has one through hole 74 on each end, and the base plate 72 has a total of six through holes 74. As a result, by using the base plate 72, it is possible to simultaneously drive two piles 30 into the ground with a specified pile interval between them.

<How to install the pile guide and base plate>

To install the pile guide device 70 and base plate 72 on the ground surface, a worker first installs the base plate 72 on or near the ground surface. Then, using each through-hole 74 of the installed base plate 72 as a visual target, the worker positions the pile guide device 70 so that each guide pipe 80 and each through-hole (guide hole, positioning hole, etc.) 74 are aligned in a straight line.

<How to guide the pile while driving it>

Figure 7 shows a side cross-sectional view of how the pile 30 is guided vertically by the guide pipe 80 and base plate 72 as the pile 30 is driven into the ground.

In this embodiment, one pile 30 is guided by being slidably fitted into two guides, the base plate 72 and the guide pipe 80, at two different locations in the axial direction. However, the present invention may also be implemented in a manner in which one pile 30 is guided at only one location in the axial direction. This may be implemented in a manner in which only the guide pipe 80 is used, or in a manner in which only the base plate 72 is used.

In this embodiment, when the pile 30 passes through the through hole 74 of the base plate 72, the guide pipe 80 also passes through the same through hole 74. As a result, at the position of the base plate 72, i.e., for example, at or near the ground surface, the outer peripheral surface of the guide pipe 80 comes into contact with the inner peripheral surface of the through hole 74, and at the same time, the inner peripheral surface of the same guide pipe 80 comes into contact with the outer peripheral surface of the pile 30.

As a result, the base plate 72, guide pipe 80 and pile 30 are stacked in three layers in the diametric direction. The structure is a triple structure consisting of the pile 30 as the innermost tube or innermost layer, the guide pipe 80 as the intermediate tube or intermediate layer, and the base plate 72 as the outermost tube or outermost layer. This prevents the center line of the pile 30 from shifting laterally parallel to the center line of the through hole 74 of the base plate 72, and also prevents the center line of the pile 30 from tilting relative to the center line of the through hole 74.

In this embodiment, the lower end of the guide pipe 80 is embedded in the ground so as to protrude from the underside of the base plate 72, so that the lower end of the guide pipe 80 is prevented from coming off the base plate 72 upward during driving of the pile 30. However, the initial protruding length may be sufficient to be about 20 mm.

＜Signboard installation work＞

Figure 8 shows an example of a process diagram in which the pole fixing method is carried out, in which a worker installs the signboard 20 shown in Figure 1 on a site prior to use.

1. Topsoil preparation process

When the installation work begins, as shown in FIG. 8, the first step is to prepare the topsoil. Specifically, a worker conducts a topographical survey (e.g., a survey of the slope of the ground surface) and a soil survey (e.g., a survey of the softness of the ground) for the area of the site where the signboard 20 is to be installed. The worker then decides on the planned installation location for the signboard 20.

Next, if the ground surface of the original ground where the signboard 20 is to be installed is not horizontal, the worker excavates at least the topsoil of the intended installation location, i.e., the topsoil of the area including the silhouette of the installed signboard 20 when projected from directly above, as illustrated in the side cross-sectional view of Figure 9 (where the base plate 72 is composed of only one steel plate 120), thereby creating a horizontal excavation surface, i.e., a construction base surface, for the installation of the signboard 20.

2. Upper and lower guide installation process

Next, as shown in FIG. 8, the upper and lower guide installation process is carried out as the second step. Specifically, the worker installs the base plate 72 as the lower guide on the construction base surface, as shown in FIG. 9.

After installing the base plate 72, the worker positions and installs the pile guide 70 on the construction base surface, using the two through holes 74, 74 of the previously installed base plate 72 as visual targets relative to the two guide pipes 80, 80 of the pile guide 70 to be installed.

Furthermore, as shown in FIG. 13(a), the worker installs the pile guide device 70 on the construction base surface relative to the base plate 72 so that the guide pipe 80 passes through the through hole 74 of the base plate 72.

The worker then adjusts the length of at least one of the four support pipes 90 of the installed pile guide device 70 by manipulating the corresponding jack base 92, so that all of the guide pipes 80 extend vertically and at the same time, the guide pipes 80 extend parallel to each other. As a result, as shown in FIG. 7, the center lines of the guide pipes 80 and the center lines of the corresponding through holes 74 coincide with each other.

3. Pile driving process

Next, as shown in Figure 8, the pile driving process is carried out as the third step.

Specifically, the worker repeatedly drives the pile 30 into the ground and pulls it out. After each pull, the worker pours sand as filler into the vertical hole 140 (see Figure 7) created in the ground.

With each subsequent repeated driving, the same pile 30 compacts the sand layer 150 (see FIG. 7) and the surrounding soil that were poured into the vertical hole 140 while gradually expanding them outward. When the compaction is completed, the worker leaves the pile 30 in the ground with its upper end protruding from the ground surface, thereby fixing the pile 30 to the ground.

Figure 10 shows multiple cross-sectional views to explain in chronological order the pile driving process, in which piles are repeatedly driven into and pulled out of the ground, and sand is poured into the vertical hole 140 created in the ground after each pullout as a filler material.

The figure shows the chronological changes in the ground cross section for the first (n=1) cycle, the nth cycle, and the final cycle out of the multiple cycles that make up one pile driving process.

In the final cycle, after driving the pile 30 into the ground, the worker applies rotational force, axial force, vibration (e.g., sound waves) to the pile 30 and subjectively or objectively using a sensor to evaluate whether the degree of compaction (e.g., earth pressure) of the sand layer 150 and the surrounding soil has reached a target value.

When the desired degree of soil compaction is achieved, the worker leaves the pile 30 in the ground.

In each cycle, the pile 30 is driven in step by step, for example, by an operator repeatedly free-falling a pile driving hammer 200 shown in FIG. 11. The pile driving hammer 200 has, for example, a generally cylindrical weight section 202 having a bottomed hole extending upward from its lower end, and a pair of grips 204, 204 extending from the outer periphery of the weight section 202.

As shown in FIG. 7, the total length of the pile 30 is longer than the total length of the guide pipe 80. Therefore, when the pile 30 is driven into the ground to a position where its top end is approximately the same as the top end of the guide pipe 80, the top end position of the pile 30, i.e., the pile head level, is approximately the same as the position where it has risen from the ground surface into the air to a height approximately equal to the total length of the guide pipe 80. At this time, the pile tip depth, which is the depth of the tip 52, i.e., the tip of the pile 30 driven into the ground, is approximately the same as the position where it has descended from the ground surface into the ground by the length of the part obtained by subtracting the total length of the guide pipe 80 from the total length of the pile 30.

The appropriate value of the pile tip depth depends on the softness of the soil into which the pile 30 is to be driven , but the pile tip depth is selected to be, for example, approximately 700 mm or more, as shown in FIG. 13(b).

In contrast, in each cycle, the extraction of the pile 30 is performed step by step, for example, by an operator repeatedly operating a pile extractor 300 as shown in FIG. 12.

The pile puller 300 has, for example, a base 302 that is grounded, a lever 304, and an engagement device 306 that removably engages with the pile 30. The lever 304 has a force point operated by an operator, a fulcrum supported by the base 302, and a point of action that is swingably connected to the engagement device (for example, a metal fitting with a U-shaped gripping portion that matches the diameter of the pipe to be pulled out) 306.

When the worker repeatedly tilts the lever 304 in the direction pulling it toward himself, the operating force applied by the worker to the force point of the lever 304 is multiplied by the principle of leverage. This multiplied operating force is transmitted to the pile 30 via the engaging device 306 as a pulling force.

When using this pile puller 300 to pull out the pile 30, as shown in Figure 7, the guide pipe 80 prevents the pile puller 300 from directly accessing the outer periphery of the pile 30, so before each extraction, the worker must temporarily pull out the guide pipe 80 from the pile 30 that has been driven into the ground.

Therefore, the worker first unlocks the orthogonal clamp related to the guide pipe 80 in the pile guide tool 70, thereby making the guide pipe 80 separable from the pile guide tool 70. In this state, the worker pulls out the guide pipe 80 from the ground. After that, the worker attaches the pile puller 300 to the pile 30.

Once the pile 30 has been pulled out, the worker replaces the removed guide pipe 80 in the pile guide tool 70 in its original position, and the next driving is then performed using the same guide pipe 80.

4. Pile guide removal process

Next, as shown in FIG. 8, the pile guide device removal process is carried out as the fourth step. Specifically, the worker removes and recovers the pile guide device 70 from the ground surface. At that time, the worker leaves the base plate 72 on the ground surface.

As a result, after the signboard 20 is installed, the base plate 72 functions as a member that reinforces the pair of posts 22, 22 of the signboard 20 on the ground surface or underground (for example, a tie bar that horizontally restrains the pair of posts 22, 22).

5. Pillar connection process

Then, as shown in FIG. 8, the fifth step is the post connection process. Specifically, after the piles 30 are fixed to the ground as described above, the worker uses the parts of the piles 30 fixed to the ground that protrude above the ground surface to connect each post 22 of the signboard 20 to the piles 30 coaxially and in contact with each other, as shown in FIG. 13(b).

Figure 13(b) is a side cross-sectional view for explaining the relative positional relationship between the pile 30, the support 22, the reinforcing sleeve 400, and the base plate 72 during this support connecting process. Also, Figure 14 is a cross-sectional view for explaining the relative positional relationship between the pile 30, the support 22, and the reinforcing sleeve 400 during this support connecting process.

Specifically, in this post connection process, the worker first coaxially covers the portion of the pile 30 that protrudes above the ground surface with a reinforcing sleeve 400 (made of a round pipe in the illustrated example, but it can also be made of a square pipe).

Next, the worker coaxially covers the hollow hole at the lower end of the post 22 (made of a square pipe in the illustrated example, but it can also be made of a round pipe) over the reinforcing sleeve 400. In this way, the worker connects the pile 30 and the post 22 to each other in a triple-tube type connection structure, using the reinforcing sleeve 400 as an intermediary between them.

At this time, as shown in FIG. 13(b), the worker embeds the reinforcing sleeve 400 in the ground so that its lower end passes through the through hole 74 of the base plate 72 and then sinks deeper, for example to a tip depth of about 100 to about 200 mm. The worker may embed the reinforcing sleeve 400 by striking the upper end surface of the reinforcing sleeve 400 with a hammer.

As shown in FIG. 13(b), the reinforcing sleeve 400 is embedded in the ground, completely penetrating the through-hole 74 of the base plate 72. This realizes a layout that reduces the gap between the outer peripheral surface of the pile 30 and the inner peripheral surface of the through-hole 74 of the base plate 72. This layout prevents the pile 30 and the support 22 from wobbling sideways within the through-hole 74, and the reinforcing sleeve 400 embedded in the ground strengthens the ground, improving the postural stability of the pile 30 and the support 22.

In this post connection process, the worker further tightens and fixes the post 22 to the pile 30 using a fastener 60, as shown in FIG. 4. This prevents the post 22 from coming loose in the axial direction from the pile 30. The fastener 60 tightens and fixes the post 22 at at least one axial position that is not covered by the reinforcing sleeve 400, as shown in FIG. 13(b).

However, prior to carrying out this post connection process, each post 22 can be in a state where it is already attached to the signboard 40 along with the other posts 22 that make up its pair and cannot move freely on its own, i.e. the signboard 20 is in a completed state except for the stakes 30, or the post 22 has not yet been attached to the signboard 40 and can be separated from the other parts and move freely, i.e. the signboard 20 is in an incomplete state. This embodiment can be applied under either option.

However, in one example of this embodiment, the former option is adopted. This allows the work of attaching each support 22 to the display board 40 to be done on flat ground, and in parallel with the construction of the piles 30, which has the advantage of improving work efficiency.

On the other hand, when the main body of the signboard 20 is completed, it is necessary to connect the pair of posts 22, 22, whose relative positions are fixed, to a pair of piles 30, 30 driven into the ground, whose relative positions are also fixed. Therefore, a nearly perfect geometric coincidence is required between the center lines of the pair of posts 22, 22 and the center lines of the pair of piles 30, 30.

Here, "nearly perfect geometric consistency" means that the pair of posts 22, 22 are almost perfectly parallel to each other, the pair of piles 30, 30 are almost perfectly parallel to each other, and the spacing between the pair of posts 22, 22 and the spacing between the pair of piles 30, 30 almost perfectly match each other.

In this way, to meet the requirement of almost perfect geometric alignment between a pair of posts 22, 22 and a pair of piles 30, 30, in this embodiment, a pile guide device 70 that adjusts the orientation of the upper part of each pile 30 and a base plate 72 that adjusts the orientation of the lower part of each pile 30 are used in combination to accurately match the actual orientation of each pile 30 to the target one.

6. Backfilling process with topsoil

Then, as shown in FIG. 8, a sixth step, a topsoil backfilling process, is carried out. Specifically, as shown in FIG. 13(b), workers pile up soil to bury the base plate 72 in the ground. If the original ground surface was a slope, soil is piled up on the base plate 72 to match the original ground surface, and the initially excavated portion is backfilled and restored.

This completes the installation of one signboard without the use of heavy machinery or excavation of the ground, and is completed through simple manual work by the worker, without requiring advanced skills or years of experience.

＜Signboard removal work＞

Figure 15 shows an example of a process diagram showing the removal work in which a worker removes the signboard 20 after use has ended.

＜1. Dismantling process＞

As shown in the figure, the first step is a dismantling process. Specifically, a worker loosens the fasteners 60 to separate each support 22 from the pile 30 to which it is connected. As a result, a pair of piles 30, 30, each covered by their respective reinforcing sleeves 400, protrudes from the ground surface.

＜2. Pile removal process＞

Next, as shown in the figure, the second step is the pile removal process.

Specifically, first, an operator manually pulls out each reinforcing sleeve 400 from each pile 30 using a first pile puller 300 having an engagement tool 306 that fits the diameter of the reinforcing sleeve 400.

Then, the worker manually pulls out each pile 30 from the ground using a second pile puller 300 (which may be the same as the one used in the pile driving process during the installation work described above) that has an engagement tool 306 that fits the diameter of the piles 30. As a result, a pair of vertical holes 140, 140 created by the pair of piles 30, 30 remains in the ground.

＜3. Base plate removal process＞

Then, as shown in the figure, the base plate removal process is carried out as the third step. Specifically, first, workers remove the soil covering the buried base plate 72, resulting in the base plate 72 being exposed. Next, workers remove and recover the base plate 72 from the ground surface.

＜4. Topsoil restoration process＞

Next, as shown in the figure, the topsoil restoration process is carried out as the fourth step. Specifically, workers fill in and level the areas of the site where the topsoil has not been leveled because the victory sign 20 was removed by appropriately piling up soil.

This completes one signboard removal operation without the use of heavy machinery or excavation of the ground, and is completed by simple manual labor by the worker, without requiring advanced skills or years of experience.

In this embodiment, in the pile driving process shown in FIG. 8, the driving and pulling out of the pile 30 and the pouring of sand are repeated. However, for example, if the ground on which the signboard 20 is to be installed is not weak, the pile 30 may be driven only once and the pouring of sand into the vertical hole 140 may be omitted.

However, even in this case, by using the pile guide 70 and base plate 72 and/or the aforementioned triple-tube connecting structure between the pile 30 and the support 22, the reliability of the installation of the support 22 (pile spacing and verticality/parallelism) can be ensured, and/or the connecting strength of the support 22 (e.g., bending rigidity) can be ensured.

The above describes an exemplary scenario in which the posts 22, 22 of a signboard 20 are fixed to the ground of a site (e.g., used as a parking lot) using the ingenious pile driving method according to this embodiment, but the same pile construction method can also be used to install other equipment used together with the signboard 20 on a similar site, such as box-shaped bodies such as ticket vending machines, ticket issuing machines, and payment machines, and posts (e.g., hollow cylindrical bodies) to which equipment such as security lights can be attached.

For example, when a ticket vending machine having a hollow box-shaped frame (e.g., a hollow box-shaped body) is to be installed on a site, one or more piles 30 driven into the ground using the same piling method are inserted into the central hole in the bottom plate of the box-shaped frame, thereby firmly connecting the ticket vending machine to the piles 30.

<Advantages of the driving pile method according to this embodiment over the root-wrap pile method>

1. The advantage of shortening construction time

The applicant carried out a test construction in which one signboard 20, one ticket machine, and five security lights were all installed together on the same site. During the test construction, the time spent installing multiple piles 30 using the unique pile driving method according to this embodiment was approximately four hours.

In contrast, when constructing multiple posts 22 (including a pair of posts for a signboard 20, multiple posts for a ticket machine, and multiple posts for multiple security lights) using the aforementioned root-wrapping pile method, a worker will, for example, carry out the following multiple steps in order.

(1) The process of drilling pilot holes into the ground in the same number as the number of supports 22.

(2) The process of preparing ready-mix concrete (or mortar) for all the columns 22

(3) The process of inserting all the posts 22 into their respective pilot holes and installing them on the site (however, the pair of posts 22, 22 for the signboard 20 are inserted into their respective pilot holes and installed on the site in the state where both are attached to the display board 30, i.e., in the completed state of the signboard 20)

(4) Pouring the prepared ready-mix concrete into multiple pilot holes

(5) The process of aligning the installed signboard 20 so that its lateral direction almost perfectly coincides with the horizontal direction.

(6) A process of installing reinforcing diagonal members (braces) at the lower ends (e.g., the parts protruding from the ground surface) of the pillars 22 to prevent them from tilting or falling over unintentionally before the fresh concrete in each pilot hole has completely solidified.

(7) Waiting until the fresh concrete hardens

As a comparative test to the above test construction, the applicant used the root-wrapping pile method to drive the same number of posts 22 into the ground as the multiple piles 30 used in the above test construction, and this took two days.

As is clear from the above explanation, according to this embodiment, the construction of the piles 30 can be completed in a significantly shorter time than when using the root-wrapping pile construction method, shortening the construction period required for pile construction and, accordingly, reducing the construction costs required for pile construction.

Furthermore, according to this embodiment, while multiple piles 30 are usually constructed in sequence, rather than all at once, once the construction of one pile 30 is completed in a few hours, another worker can carry out another task related to that pile 30. As a result, according to this embodiment, construction of another pile 30 can be carried out in parallel with the work related to a completed pile 30. Here, "another task" is, for example, electrical work carried out on the signboard 20. Such electrical work includes the installation of a sign light for night lighting on the top of the signboard 20 and wiring work to supply power to the sign light.

Therefore, according to this embodiment, multiple types of work required on the same site can be performed at least partially simultaneously in parallel, improving overall work efficiency.

In contrast, when using the root-wrapping pile method, work associated with any of the pillars 22 (such as necessary electrical work) cannot be carried out until the concrete has hardened for all of the pillars 22. Therefore, work associated with those pillars 22 must be started in series rather than in parallel, waiting until the concrete foundations for all of the pillars 22 are complete.

As a result, when using the root-wrapping pile method, multiple types of work can only be performed with efficiency significantly lower than the work efficiency of this embodiment.

2. The advantage is that the underground installation space for piles is reduced.

As is clear from the above explanation, in this embodiment, before the support 22 is fixed to the ground, the pile 30 is driven into the ground, and at this time, the pile 30 functions as a hole-drilling tool, thereby creating a vertical hole 140 in the ground with a diameter approximately the same as that of the pile 30.

According to the aforementioned root-wrap pile method, a pilot hole is drilled in the ground before the post is buried in the ground. The pilot hole is drilled to have a cross section larger than the outer diameter of the post, taking into account the size of the concrete foundation that will surround the bottom end of the post when it is buried in the pilot hole.

Furthermore, with this root-wrap pile construction method, as mentioned above, before the concrete foundation hardens, the reinforcing diagonal members are attached to the lower end of each pillar so that they extend laterally from the pillar, so extra space is required on the ground surface to be occupied by the reinforcing diagonal members.

Therefore, when using this root-wrapped pile construction method, when installing the piles on a site near the boundary line with the neighboring property, it is necessary to move the posts away from the boundary line toward the site so that the pilot holes, concrete foundations, and reinforcing diagonal members do not intrude into the neighboring property. Therefore, when using this root-wrapped pile construction method, it is difficult to install the posts as close to the boundary line as possible on the site, thereby minimizing the possibility of the posts becoming an obstacle on the site.

In contrast, according to this embodiment, the vertical hole 140 is constructed in the ground at the same position as the pile 30 and with approximately the same diameter, and the depth of each pile 30 is deep enough (e.g., 700 mm, 800 mm, or 900 mm or more) that the reinforcing diagonal members required for the root-wrapping pile method are not required, making it easy to install the pile 30 and the support 22 connected to it as close as possible to the boundary line within the site.

In the embodiment described above, the support 22 and the pile 30 are coaxially connected to each other in a triple-cylinder structure via a reinforcing sleeve 400 as a third member or intermediate member.

In contrast, in one modified example, as illustrated in Figures 19(a) and (b), the pile 30 and the support 22 are coaxially connected to each other in a double-tube structure without using a third member or intermediate member.

Figure (a) is a partial plan cross-sectional view showing the coaxial connection structure between the pile 30 and the support 22 connected to it after driving, and Figure (b) is a side cross-sectional view showing the coaxial connection structure.

The coaxial connection structure has a plurality of guide plates 600 fixed discretely in the axial direction within the central hole 22b of the lower end 22a of the support 22. The number of guide plates 600 may be two as shown in the figure, or may be more than that, for example, three or four.

At the lower end 22a of the support 22 (the portion of the support 22 that connects to the upper end of the pile 30), the greater the number of guide plates 600 per given axial length (the higher the density), the less the load acting on the connection point between the support 22 and the pile 30 via each guide plate 600. Therefore, the higher the density of the guide plates 600, the more widely the load is distributed in the axial direction at the connection between the support 22 and the pile 30, and the stress is distributed over a wide area without concentrating locally. As a result, stress concentration is mitigated.

Each guide plate 600 is generally plate-shaped, and in one example, has a support portion 602 having an outer shape smaller than the cross-sectional shape of the central hole 22b (e.g., an outer shape that allows the guide plate 600 to pass through the central hole 22b in a specified position), and an attachment portion 604 bent at one end of the support portion 602. The support portion 602 and the attachment portion 604 may be configured as an integrated part or as separate parts.

The support portion 602 has a through hole 603 through which the pile 30 passes, thereby fixing the radial position of the pile 300.

In contrast, the mounting portion 604 is attached to a predetermined axial position of the central hole 22b. The attachment is performed, for example, by screwing or welding to the side wall of the support 22.

Furthermore, this mounting portion 604 is used to fix the support 22 and the pile 30 in a predetermined axial direction using a fastener 610 such as a set screw (a male screw for pressing its tip against a mating member to fix the mating member).

The fastener 610 is screwed into a female thread formed in a penetrating state in the side wall of the support 22 (in this case, a through hole is formed in the mounting portion 604) or into a female thread formed in the mounting portion 604 (in this case, a through hole is formed in the side wall of the support 22). In this screwed state, the fastener 610 engages with the outer surface of the pile 30 at its tip. This engagement presses the pile 30 against the inner peripheral surface of the through hole 603 of the guide plate 600. This pressing position the support 22 with respect to the pile 30 in both the axial and radial directions, and prevents the support 22 from coming off the pile 30 in the axial direction.

When this coaxial connection structure is adopted, the pillar connection process includes, for example, after the pile guide 70 is removed from the ground surface, (a) a process in which an operator coaxially covers the hollow hole 22b of the lower end 22a of the pillar 22 over the portion of the pile 30 protruding from the ground surface, thereby coaxially inserting the protruding portion into the hollow hole 22b, and (b) a process in which the lower end 22a is fixed, joined or fastened to the protruding portion, thereby coaxially connecting the pile 30 and the pillar 22 to each other with a double-tube structure.

<Another embodiment>

Next, referring to Figures 16 to 18, a signboard according to another exemplary embodiment of the present invention will be described. However, elements common to the previous embodiment will be referred to using the same reference numerals or names to avoid duplicated explanations, and only the different elements will be described in detail.

As shown in FIG. 1, the signboard 20 has a pair of posts 22, 22, and in one example, each post 22 is configured as a square pipe.

Incidentally, when the signboard 20 is used, for example, as a parking lot signboard, a light (e.g., a security light) for illuminating the display panel 30 of the signboard 20 at night and a surveillance camera for photographing and monitoring the parking lot at all times of the day and night are detachably attached to a high point on the support pole 22, for example, near the top end.

As shown in FIG. 16, in order to detachably mount the equipment 520, 522 such as the electric light (e.g., security light) and the surveillance camera to the support 22, a clamp 500 such as the above-mentioned orthogonal clamp is used as a commercially available (standard) product. This clamp 500 is known as a mounting bracket that spans two parts, a bracket that tightens and fixes two parts, etc.

The figure shows an exemplary perspective view of how multiple types of accessories 520, 522 are removably attached to a signboard 20 using one type of clamp 500.

Figure 17 shows an enlarged plan view of a clamp 500 that is detachably attached to a support 22 made of a square pipe, in the locked and unlocked positions. The example shown is a parallel clamp (or a free clamp) that clamps two pipes parallel to each other, but it is also possible to use an orthogonal clamp (or a fixed clamp) that clamps two pipes in a position where they intersect at right angles, as shown in Figures 16 and 18.

As shown in FIG. 17, regardless of the type, the clamp 500 has a first holding part 504 for detachably holding a first pipe 502 (e.g., a support 22 made of a square pipe) and a second holding part 508 for detachably holding a second pipe 506 (e.g., a round pipe 506 of an adapter 530, 532 (described in detail later with reference to FIG. 18) used to attach accessories 520, 522). The holding parts 504, 508 are connected by a connecting part 510 so that they cannot be displaced relative to each other if the clamp is fixed, or so that they can be displaced relative to each other if the clamp is flexible.

The first holding portion 504 can be switched between a locked position shown by a two-dot chain line in the figure, where the first pipe 502 is fixed to the clamp 500, and an unlocked position shown by a solid line in the figure, where the first pipe 502 can be released from the clamp 500.

Similarly, the second holding portion 508 also switches between a locked position shown by a two-dot chain line in the figure, i.e., a position where the second pipe 506 is fixed to the clamp 500, and an unlocked position shown by a solid line in the figure, i.e., a position where the second pipe 506 can be released from the clamp 500.

Figure 18(a) is a plan view conceptually showing a clamp 500 together with a first adapter 530 attached thereto, and figure 18(b) is a plan view conceptually showing the same clamp 500 together with a second adapter 532 attached thereto.

In this embodiment, first and second adapters 530, 532 made to match the geometric characteristics of the fittings 520, 522 are used to attach the fittings 520, 522 to the first pipe 502 by the clamp 500. Specifically, the first adapter 530 is used to attach the first fitting 520 to the clamp 500, while the second adapter 532 is used to attach the second fitting 522 to the same clamp 500.

Each of the adapters 530, 532 is constructed as a two-part structure, specifically, including an attachment 550 as a first part that is attached to the mounting bracket 540 of the equipment 520, 522, and a second pipe 506 as a second part that is held by the second holding part 508.

The attachment 550 is a dedicated item for the equipment 520, 522 to which it is to be attached, at least in terms of the mounting specifications (e.g., the number and arrangement of screw holes), whereas the second pipe 506 corresponds one-to-one to the type of the corresponding clamp 500 and is a common item for the equipment 520, 522 to which it is to be attached. Usually, the attachment 550 and the second pipe 506 are manufactured separately, and then the two are joined together to form the adapter 530, 532 as a single completed product.

When the mounting bracket 540 and the attachment 550 are screwed together, the same number of screw holes 560, 562 are formed in the same arrangement (e.g., pitch and direction) in both the mounting bracket 540 and the attachment 550. However, the mounting specifications of the mounting bracket 540 (the number and arrangement of the screw holes 560) differ depending on the type of the accessories 520, 522.

Therefore, adapters 530, 532 exist for each type (type of mounting specification) of the equipment 520, 522. However, in the adapters 530, 532, the second pipe 506 is common regardless of the type of equipment 520, 522, whereas the attachment 550 differs depending on the type (type of mounting specification) of the equipment 520, 522.

Therefore, the adapters 530, 532 are common to the second pipe 506 regardless of the type, so only one type of clamp 500 is required. On the other hand, the adapters 530, 532 are dedicated to each of the equipment 520, 522 because the attachment 550 differs depending on the type of equipment 520, 522.

In the past, in order to install the equipment 520, 522 at a high point on the support 22 at a work site (e.g., a parking lot), a worker would drill holes in the wall of the support 22 according to the installation specifications of the equipment 520, 522 while working at the high point.

In contrast, according to this embodiment, the same drilling work can be performed not on-site, but at a production site such as a factory before the attachment is transported to the site, by the same worker who will be going to the installation site, or by a different worker who will not be going to the installation site, as work on flat ground or at a low altitude. Therefore, according to this embodiment, it is no longer necessary to perform drilling work at a high altitude, reducing the burden on the worker.

Furthermore, according to this embodiment, multiple types of accessories 520, 522 are not directly attached to the clamp 500, but are indirectly attached to the clamp 500 via corresponding adapters 530, 532. Therefore, according to this embodiment, regardless of the types of accessories 520, 522 to be attached, the type of clamp 500 is unified to one type as long as the type of support 22 is the same. As a result, storage and management of the clamp 500 before use is easy.

In other words, according to this embodiment, the compatibility or versatility of the clamp 500 with the types of accessories 520, 522 is expanded thanks to the presence of the adapters 530, 532.

Furthermore, according to this embodiment, the clamp 500 that arrived at the site is not genuine and therefore does not match the equipment 520, 522 that arrived at the site together with the clamp 500, so there is no need to take the extra effort of transporting a different genuine clamp 500 to the same site.

As is clear from the above explanation, this embodiment has been made to solve the problem of wanting to reduce the burden on an operator who uses a commercially available clamp (e.g., a two-component connecting type) to attach a second object (e.g., equipment 520, 522) to a first object (e.g., a support 22) due to an increase in the number of second objects that may be attached to the same type of first object.

To solve this problem, the present embodiment employs the following technical ideas:

That is, based on (a) a first technical idea of using a commercially available or standardized clamp to attach a second object (e.g., equipment 520, 522) to a first object (e.g., support 22), and (b) a second technical idea of indirectly gripping the second object with the clamp via an adapter, configuring the adapter as a connection between a first part that is attached to the second object and a second part that is gripped by the clamp, and manufacturing the first part to have different geometries depending on the type of second object, while manufacturing the second part to have only one type of geometry as long as there is only one type of clamp, an adapter-interposed object attachment method or a clamp adapter is adopted as a means for solving the problem.

As is self-evident from the above description, this embodiment allows a worker to use only one type of clamp at any of multiple work sites to detachably attach any type of second object to one type of first object (e.g., working at height), and has the effect of simplifying the associated work (e.g., storing and managing the clamps).

In this embodiment, the "adapter" is interposed between the clamp and the second object as exemplified above, but instead, it may be interposed between the clamp and the first object, or may be embodied as a combination of a first adapter interposed between the clamp and the first object and a second adapter interposed between the clamp and the second object.

For example, JP 2017-127272 A is a prior art document that relates to a clamp as a tool for connecting multiple components to each other so that they intersect over one another.

Although several exemplary embodiments of the present invention have been described in detail above with reference to the drawings, these are merely examples, and the present invention can be embodied in other forms that incorporate various modifications and improvements based on the knowledge of those skilled in the art, including the forms described in the "Summary of the Invention" section above.

Claims (5)

A method for fixing at least one support column to the ground by using at least one steel pile, which is made of steel and is configured to have no nodes at least at its axial center, as a foundation instead of using a concrete foundation, the method comprising the steps of:
a pile driving process in which a vertical hole is created in the ground by driving the pile into the original ground where a pilot hole has not been excavated in advance, and then the pile is pulled out and sand is poured into the vertical hole as a filler without adding cement, and then the sand poured into the vertical hole and the surrounding soil are compacted while being gradually pushed outward by driving the pile, and when compaction is completed, the pile is left in the ground with its upper end protruding from the ground surface, thereby fixing the pile to the ground;
and a post connecting step of connecting the support to the pile using a portion of the pile fixed to the ground that protrudes above the ground surface after the pile is fixed to the ground. The post fixing method according to claim 1 further includes a guide installation step of installing a pile guide device that guides the pile so that it can move up and down, and a pile positioning device that positions the pile horizontally on the ground surface, prior to driving the pile. The pile guide tool is
A guide pipe into which the pile is fitted so as to be axially slidable;
and a direction adjustment mechanism for adjusting the direction of the guide pipe;
3. The post fixing method according to claim 2, wherein the guide installation step includes a step of adjusting the orientation of the pile guide device by using the orientation adjustment mechanism so that the guide pipe extends in a vertical direction. A method for driving a steel pile into the ground, the pile being configured to have no nodes at least at a central portion of the pile in an axial direction, comprising the steps of :
This pile driving method creates a vertical hole in the ground by driving the pile into the original ground where a pilot hole has not been excavated in advance, pours sand as a filler without adding cement into the vertical hole that appears when the pile is then pulled out, and compacts the sand and the surrounding soil that have been poured into the vertical hole while gradually pushing them outward as the pile is then driven in, and when compaction is complete, leaves the pile in the ground, thereby fixing the pile to the ground. The pile is transferred from an installation stage in which the pile is fixed to the ground and installed by the pile driving method according to claim 4 to a removal stage in which the pile is pulled out from the ground and removed,
The pile driving method according to claim 4, wherein in the installation stage, the pile is driven into the ground so that when the pile is pulled out in the removal stage, the vertical hole created in the installation stage can appear in the ground.

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