JP3850802B2 - Steel pile and its construction method - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
TECHNICAL FIELD The present invention relates to a steel pile having a jet nozzle and projections for jetting water or a fluidized solidifying material, and a method for constructing a steel pile using the same, and in particular, excavating the ground using a vibro hammer and water jet together. The present invention relates to a technical field in which a high-strength pile is constructed by injecting a fluidized solidified material from an injection nozzle after driving the substrate into a ground support layer.
[0002]
[Prior art]
The pile is generally driven by a pile driving machine having a large hitting force such as a diesel hammer or a hydraulic hammer. However, since these pile driving methods are noisy, low noise vibratory hammers are often used.
[0003]
By the way, if a vibration is applied to the pile by a vibro hammer and a liquid with a low pressure and a low flow rate is supplied, the pile can be easily sunk, but the ground surface of the pile is loosened by the vibration, so the peripheral friction force of the pile is small. Become.
[0004]
Therefore, countermeasures are taken by the construction method using a vibro hammer disclosed in Patent Literature 1 and Patent Literature 2, or the construction method using digging agitation and cement milk disclosed in Patent Literature 3 and Patent Literature 4. For example, as disclosed in Patent Document 1, when a pile is submerged while being vibrated, a material added with water and liquid and a material that has the effect of solidifying is supplied at a low pressure near the tip of the pile. To do.
[0005]
The above-described vibratory hammer is also used when a concrete or steel sheet pile is pushed into the ground in civil engineering work such as revetments and retaining walls. In Patent Document 2, a sheet pile is driven after a leading pile is driven and a hole is made in the ground, or high pressure water is ejected from a water conduit piped on the outer wall of the sheet pile, and the sheet pile is driven while cutting the ground. Steel pipe piles are also used when the support layer made of sand, gravel and hard clay layer is deep from the ground surface, and when the support layer is very deep, the steel pipe piles are connected by a welded joint.
[0006]
In patent document 3, the protrusion is provided in the steel pipe pile over substantially the full length of the outer peripheral surface, and the protrusion is provided also in the inner peripheral surface at the front-end | tip part. This steel pipe pile is embedded in the support layer. As a result, the steel pipe pile is fixed to the support layer via the soil cement, so that it is possible to expect a large pile support force.
[0007]
In patent document 4, high pressure injection of cement milk is carried out in the ground from the front-end | tip of a steel pipe pile. Since cement milk is sprayed at a high pressure in the horizontal direction, the soil is improved by injecting cement milk to a larger diameter range than the steel pipe pile to form a soil cement pillar. According to this technique, the amount of soil discharged is small, the integration of the existing pile and the improved ground can be enhanced, and the peripheral surface friction force and the tip support force of the pile can be ensured.
[0008]
[Patent Document 1]
Japanese Patent Laid-Open No. 56-167026 [Patent Document 2]
JP-A-57-238544 [Patent Document 3]
JP-A-63-97711 [Patent Document 4]
Japanese Patent Laid-Open No. 64-48926
[Problems to be solved by the invention]
However, the construction method using the vibro hammer described in Patent Document 1 and Patent Document 2 is excellent in workability in terms of the driving speed and the ease of driving into the hard ground, but has a drawback of being inferior in supporting force characteristics. In addition, in the method using the excavation stirring and cement milk disclosed in Patent Document 3 and Patent Document 4, although the bearing capacity is excellent, there is a problem in terms of workability such as ease of driving into hard ground including gravel. There is.
[0010]
Then, this invention makes it the subject to aim at the further increase of the surrounding surface frictional force of a pile, and a tip support force by using together the steel pile which has a protrusion, and injection of a vibro hammer and water or a fluid solidification material. To do.
[0011]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides a steel pile having the following configuration and a construction method thereof.
(1) A steel pile according to claim 1 is a steel pile driven by using a vibro hammer and water or a jet of fluidized solidifying material, and the outer surface of the pile, the inner surface of the pile or the inner and outer sides of the pile near the tip of the pile. A flat plate-like protrusion having a plate surface parallel to the driving direction of the steel pile provided on both surfaces, and a spiral protrusion provided on the outer surface of the pile or the inner surface of the pile or both the inner and outer surfaces of the pile in the portion where the protrusion is attached One or more injection nozzles for injecting water or a fluidized solidifying material are mounted on the outer surface of the pile, the inner surface of the pile, or both the inner and outer surfaces of the pile near the tip of the steel pile.
[0012]
(2) The steel pile according to claim 2 is the steel pile according to claim 1, wherein the injection nozzle is detachable.
[0013]
(3) The steel pile according to claim 3 is the steel pile according to claim 1 or 2, wherein an injection direction by the injection nozzle is perpendicular to the driving direction of the steel pile and the driving direction. It is characterized by being in any direction between.
[0014]
(4) A steel pile according to claim 4 is the steel pile according to any one of claims 1 to 3, wherein at least one of the injection nozzles has a rotary injection means for injecting while rotating. It is characterized by.
[0015]
(5) A steel pile according to claim 5 is the steel pile according to any one of claims 1 to 4, wherein at least one of the injection nozzles includes a plurality of injection holes having different injection directions. And
[0016]
(6) A steel pile according to claim 6 is the steel pile according to any one of claims 1 to 5, wherein water or fluidized solidified material sprayed from the spray nozzle mounted on the pile outer surface of the steel pile. An introduction hole or an introduction notch for taking in the inside of the steel pile is formed in the steel pile.
[0017]
(7) A steel pile construction method according to claim 7 is the construction method in which the steel pile according to any one of claims 1 to 6 is driven into the ground, using the vibro hammer and injecting water or a fluidized solidifying material. It is characterized by driving piles into the ground.
[0018]
(8) The steel pile construction method according to claim 8 is the steel pile construction method according to claim 7, wherein the first step of driving the steel pile to the support layer while injecting water, and water or a fluidized solidified material. A second step of drawing out the steel pile while injecting water, and a third step of driving the steel pile again to the support layer while injecting water or a fluidized solidifying material. Is performed one or more times.
[0019]
(9) The steel pile construction method according to claim 9 is the steel pile construction method according to claim 8, wherein the steel pile driving depth in the third step is the hammering of the steel pile in the first step. It is characterized by shallower depth.
[0020]
(10) A method for constructing a steel pile according to claim 10 is the injection of water or a fluidized solidifying material in each of the first to third steps in the method for constructing a steel pile according to any one of claims 7 to 9. The steel pile is driven or pulled out while changing either or both of the pressure and the injection amount.
[0021]
(11) A steel pile construction method according to claim 11 is the steel pile construction method according to any one of claims 7 to 10, wherein after the driving of the steel pile is completed, the fluidized solidification material is injected. The spray nozzle is pulled up.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0023]
The basic aspect of the steel pile according to the present invention has protrusions on the outer surface of the pile, the inner surface of the pile, or both the inner and outer surfaces of the pile in the vicinity of the pile tip of the steel pile, One or a plurality of spray nozzles for spraying water or a fluidized solidifying material are mounted on both sides. The steel piles of the present invention include steel pipe piles, steel pipe sheet piles, H-shaped steel piles and the like. 1A and 1B are respectively a front view (upper view) and a bottom view (lower view) schematically showing an example of a steel pile 1 according to the present invention. A plurality of flat plate-like (rectangular, trapezoidal, etc.) protrusions 2 are attached to the outer surface of the pile near the pile tip. In the example shown in the figure, four protrusions are attached every 90 degrees on the circumference. Moreover, the protrusion 2 is rectangular shape in the example of FIG. 1, and is attached by welding. In FIG. 1A, four injection nozzles 30 are attached to the outer surface near the tip every 90 degrees on the circumference, and independent pipe hoses 31 are connected to each other. This configuration is suitable, for example, when the outer diameter D of the steel pile 1 is 600 to 900 mm. In FIG. 1 (B), six partially connected injection nozzles 30 are attached to the outer surface of the pile near the tip of the pile, and a common piping hose 31 is connected. This configuration is suitable, for example, when the outer diameter D of the steel pile 1 is 600 to 900 mm. The nozzle diameter is, for example, 6 to 8 mm.
[0024]
The injection nozzle 30 may be fixed or removable. From the injection nozzle 30, a fluid solidifying material such as water (water jet) or cement milk is injected at a high pressure. In addition, although the injection nozzle 30 is attached to the outer surface and / or inner surface of the steel pile 1, the example attached to an outer surface is shown in FIG.
[0025]
FIG. 2 is an external view of another embodiment of the steel pile 1 of the present invention to which the injection nozzle 30 and the vibro hammer 20 are attached. As shown in FIG. 2, one or two or more through holes 3 may be provided in a flat plate-like (rectangular, trapezoidal, etc.) projection 2. As a result, convection in the steel pile circumference method of soil particles and water or fluidized solidification material is promoted, so that the stirring effect around the pile is increased and the adhesion with the soil cement formed by the fluidized solidification material is increased. Will improve. The number, shape, and arrangement of the through holes 3 are appropriately set so as to increase convection. Further, as long as it contributes to the promotion of convection, the number, shape, and arrangement of the through holes 3 may be different between the adjacent protrusions 2. Further, unevenness may be provided on the plate surface of the protrusion 2. For example, the protrusion 2 is manufactured using a striped steel plate or the like. This also improves the adhesion with the soil cement formed by the fluidized solidifying material. In addition, the helical protrusion 4 may exist in at least one part of the outer surface and / or inner surface of the steel pile 1 which attaches the protrusion 2. FIG.
[0026]
FIGS. 3A to 3I show various modifications of the protrusions 2 provided on the outer surface of the pile near the tip of the steel pile, the inner surface of the pile, or both the inner and outer sides of the pile. The protrusion 2 is flat (rectangular, trapezoidal, etc.). The number and shape are not limited to those illustrated. 3A to 3E are examples in which a spiral protrusion is provided on a part of the outer surface and / or the inner surface of the steel pile 1 to which the protrusion 2 is attached.
[0027]
4A to 4C are external views schematically showing various examples of the injection nozzle 30. FIG. The injection direction of the injection nozzle 30 may be any direction within the range between the driving direction of the steel pile (usually the vertical direction) and the direction perpendicular to the driving direction (usually the horizontal direction). Can be set as appropriate. In FIG. 4 (A), the injection hole 30a is provided so that the driving direction of the steel pile becomes the injection direction, and in FIG. 4 (B), the direction which makes about 45 degrees with respect to the driving direction of the steel pile. The injection hole 30a is provided so that it may become an injection direction, and in FIG.4 (C), the injection hole 30a is provided so that a direction perpendicular | vertical to the driving direction of a steel pile may become an injection direction. By making the injection direction diagonally outward or horizontal with respect to the steel pile driving direction, a composite pile with a diameter larger than the steel pile diameter (steel pile piled, cut soil particles, and flow It is possible to form a pile) that is integrated with the solidified solidified material and finally formed in the ground, and as a result, a greater support force can be obtained.
[0028]
FIG. 5 is an external view showing another embodiment of the injection nozzle 30. The illustrated injection nozzle 30 includes an injection hole 30a that injects in the horizontal direction, and includes a rotary injection unit that rotates about the axis 30b of the injection nozzle 30 as indicated by an arrow during injection. Therefore, the water or the fluidized solidifying material can be dispersed all around the spray nozzle 30 by rotating the spray nozzle 30 in a horizontal plane while spraying water or the fluidized solidifying material from the spray hole 30a. In addition, the injection hole 30a may face diagonally downward instead of the horizontal direction. Thereby, the stirring range and injection | pouring range of water or a fluidized solidification material can be expanded, and bearing capacity can be increased by the diameter increase of a synthetic pile.
[0029]
FIG. 6 is an external view showing still another embodiment of the injection nozzle 30. The illustrated injection nozzle 30 is provided with two injection holes 30a in the vertical direction and the horizontal direction. The direction of the injection hole 30a may be other than these directions, and may be directed obliquely downward. In this way, by providing a plurality of injection holes with different injection directions in one injection nozzle 30, the agitation and injection range of the water or the fluidized solidified material is expanded, and the supporting force is increased by increasing the diameter of the synthetic pile. be able to.
[0030]
FIG. 7 shows another embodiment of the steel pile of the present invention, and is a schematic partial view near the tip of the steel pile 1. As shown in FIGS. 4 to 6 above, in a given embodiment of the spray nozzle according to the present invention, water or fluidized solidified material can be sprayed in various directions other than the driving direction. Therefore, when water or a fluidized solidifying material is injected so as to hit the outer wall of the steel pile 1 (for example, horizontally or obliquely downward), the water or the fluidized solidified material can be taken into the steel pile 1 inside. An introduction hole (5a) shown in FIG. 7A or an introduction notch (5b) shown in FIG. 7B is provided. Thereby, during construction, there is an effect that a jet is introduced into the steel pile 1 so that the inside of the steel pile 1 is not blocked, and penetration is improved. Further, at the time of stopping, there is an effect that the introduced solidified material forms a solidified body and closes the inside of the tube, and the supporting force is improved.
[0031]
Next, with reference to FIG.8 and FIG.9, the effect of the protrusion 2 in the steel pile of this invention is demonstrated. When the vibratory hammer is driven, a pressure wave P0 is radiated from the surface of the steel pile 1. As shown in FIG. 8 (A), this pressure wave P0 differs depending on the location of the steel pile 1, but is represented as P0 for simplicity. The pressure wave P0 is directly incident on the protrusion 2 with the pressure P, or the pressure wave P0 is reflected by the borehole wall or the like and is incident on the protrusion 2 with the pressure P. If the reflected wave P ′ is generated, the reflected wave P ′ also increases the stirring effect. In addition, as shown in FIG. 8B, when the pressure wave P is incident on the protrusion 2 from the lateral direction to generate a reflected wave P ′, the reflected wave P ′ stirs the soil particles and the fluidized solidifying material. Promoted.
[0032]
For example, in the case of the trapezoidal protrusion 2 as shown in FIG. 9, if the pressure wave (vertical component) P1 is incident on the lower end of the protrusion 2 and reflected to the side to become the pressure wave P1 ′, the area around the pile If the pressure wave (horizontal component) P2 is incident on the lower end of the projection and reflected downward to become the pressure wave P2 ′, the crushing hole drilling force in the pile tip direction is increased. Thus, by attaching the protrusion 2, the flow range of the fluidized solidifying material can be expanded, the peripheral frictional force can be increased, the root consolidation strength of the pile foundation tip can be increased, and the water jet can be attached to the outer periphery of the steel pile. It is possible to protect the piping hose.
[0033]
FIG. 10 is an example of a construction machine layout diagram for explaining a construction method for building and driving a steel pile with projections according to the present invention. A vibro hammer grips the upper part of a steel pile with a chuck device. A vibratory hammer is a device that generates vibration by transmitting the rotational force of a motor to an eccentric member, and its performance is, for example, a motor output of 30 to 500 kW, a vibration frequency of 10 to 60 Hz, and a steel pile chuck mass of 3 to 15 tons. . For example, the steel pile is gripped at two places on the circumference. Further, in the case of a linear steel sheet pile or steel pipe sheet pile formed in a cylindrical shape for a large depth structure, it is gripped by a mechanically interlocked several to several tens of vibratory hammer chuck devices and lifted by a crane.
[0034]
In addition, the injection nozzle (not shown) attached near the front-end | tip of a steel pile functions as a water jet cutter which injects high-pressure water (for example, fresh water) of a pressure of 3-15 Mpa, for example, in combination with a vibro hammer when driving a pile. To do. In addition, in the fluidized solid material injection method used to solidify the pile tip and increase the ground strength of the peripheral surface of the pile, the fluidized solidified material is driven from the injection nozzle at a pressure of about 15 Mpa or less while driving the vibrator hammer. Spray. In addition, in the construction method of this invention mentioned later, the process of stopping the drive of a vibro hammer and injecting a fluid solidification material is also included. The piping hose is connected to a grout (fluidized solidifying material) pump and a water jet cutter device via a switching valve.
[0035]
FIG. 11 is a schematic process diagram for explaining each process in an example of a steel pile construction method according to the present invention. Although this process figure has shown about the steel pile 1 with a protrusion in this invention mentioned above, the steel pipe sheet pile with a protrusion arrange | positioned in the column shape which is another Example of this invention (shown in FIG. 13 mentioned later) and a steel sheet pile The same applies to. However, when the driving depth is very deep, the lower pile, the middle pile, and the upper pile are driven while being sequentially welded, but the description of the welding process is omitted.
[0036]
Referring to FIG. 11, the first step is a steel pile driving step. Water jet is ejected from the ejection nozzle 30, and the mass of the steel pile 1 and the vibro hammer is allowed to self-sediment, for example, about 5D to 10D (D is the outer diameter of the steel pile), and then the vibro hammer is operated. Placing continuously. The continuous casting speed is, for example, 100 cm / min. The driving speed into the support layer is, for example, about 60 cm / min or less. The confirmation of the support layer is done based on the geological survey results and cross-sectional view of the geological survey conducted in advance, and when the pile tip approaches the presumed support layer, the entire load of the vibrator hammer is deposited on the pile, and the driving speed and driving resistance are checked. (For example, a load current in the case of an electric vibratory hammer) is read.
[0037]
After the tip of the steel pile 1 passes through the interface between the intermediate layer and the support layer (support layer depth), the steel pile 1 is stopped at the driving excavation depth. In the illustrated example, the driving excavation depth is set at a position about 2.0D deeper than the support layer depth. Here, the water jet is stopped. The vibratory hammer may be temporarily stopped, but may be kept operating for the subsequent second step.
[0038]
The second step is a fluidized solid material vibration stirring step. The switching valve of the pipe to each tank of water and the fluidized solidifying material in FIG. 10 described above is operated to switch to the fluidized solidifying material flow path. Cement is supplied from a cement silo, and other injecting materials are blended to prepare a fluidized solidifying material (cement milk or the like) having a W / C of 50% to 150%. The injection of such a fluidized solidified material is started at an injection pressure of about 15 Mpa or less at maximum, and the vibro hammer is operated to pull up the steel pile 1 to the lifting depth. In the example shown in the figure, it is pulled up to a position shallower by about 1.0D than the depth of the support layer.
[0039]
Further, in the third step, the steel pile 1 is driven from the pulling depth to the fixing depth while jetting the fluidized solidified material. In the illustrated example, the fixing depth is about 1.0 D deeper than the support layer depth and shallower than the driving depth of the first step. The moving speed of the steel pile 1 in that case is about 50-200 cm / min.
[0040]
Said 2nd and 3rd continuous process may be performed only once, and may be repeated in multiple times according to conditions, such as the hardness of a ground. In the case of a hard ground, it is preferable to repeat appropriately for the stirring of the ground. In the repetition process of the second and third processes, either a fluidized solidifying material or water (that is, a water jet) may be injected. Thereby, the bulb | bulb with which the solidified body was expanded can be formed reliably in the steel pile front-end | tip, and a front-end | tip support force can be increased.
[0041]
Then, whether the second and third steps are performed only once or repeatedly, the vibro hammer is stopped after the steel pile 1 is stopped at the fixing depth by the third step performed last. Thereafter, while the steel pile 1 is stopped at the fixing depth, the fluidized solidified material is sprayed for a predetermined time as a rooting step. Process control is based on grout pump pressure gauge and flow meter.
[0042]
Next, an injection nozzle drawing process is performed. First, the injection nozzle 30 is detached from the steel pile 1 together with the pipe hose 31. Thereafter, the upper end portion of the pipe hose 31 is lifted by the main crane of the base machine, and the injection nozzle 30 is pulled out at a predetermined speed, for example, 50 to 200 cm / min. At this time, the spray nozzle 30 is pulled out while spraying the fluidized solidifying material. The injection is stopped when the injection nozzle 30 is pulled out to a predetermined ratio, for example, 90% with respect to the driving depth. By pulling out the injection nozzle while injecting the fluidized solidified material, a solidified body of the fluidized solidified material is formed on the outside of the steel pile 1, thereby increasing the peripheral frictional force.
[0043]
In each of the first to third steps, the steel pile may be driven or pulled out while changing either or both of the injection pressure or the injection amount of water or the fluidized solidifying material.
[0044]
FIG. 12 is a cross-sectional view of a pile foundation (synthetic pile) formed by the steel pile construction method according to the present invention. According to this construction method, a substantially root-like soil cement solidified body 200 having a diameter expanded as compared with the steel pile 1 is formed at the tip of the pile. The depth of the lower end of the soil cement solidified body 200 reaches the driving depth or more. That is, the portion corresponding to the tooth root of the root-like soil cement solidified body 200 is securely embedded in the support layer. It should be noted that the expression of the root shape is figurative and may not necessarily have a clear root shape depending on the ground conditions and construction conditions. In any case, reliable incorporation into the support layer is realized. Moreover, a fluid solidification material is also inject | poured inside the steel pile 1 by the 2nd process (fluid solidification material vibration stirring process), and finally becomes a part of soil cement solidification body 200. FIG. The upper end of the soil cement column inside the steel pile 1 reaches above the pulling depth because of the fluidized solidified material injected in the root-setting step. Thereby, the pile front-end | tip of the steel pile 1 is obstruct | occluded.
[0045]
Finally, the steel pile in the present invention includes a large number of straight steel sheet piles and a pile of sheet piles (steel pipe sheet piles) formed of a large number of steel pipes. FIG. 13 shows a steel pipe sheet pile foundation 100 that is an aggregate of the steel pipe sheet piles 10. A plurality of protrusions 2 are welded to the outer surfaces near the tips of the steel pipe sheet piles 10 constituting the steel pipe sheet pile foundation 100, respectively.
[0046]
【The invention's effect】
According to the steel pile of the present invention, the agitation effect of the soil particles and the fluidized solidified material around the tip of the pile is increased by the protrusion, and after solidification, the function is exhibited as a soil cement synthetic pile expanded from the steel pile diameter. As a result, the vertical supporting force from the ground is remarkably improved as compared with the case where a steel pipe without protrusions is used. Depending on the conditions, it may be improved by a factor of 2 or more.
[0047]
Moreover, according to the construction method of the steel pile of this invention, in the said 1st-3rd process, a fluid solidification material is sprayed from the steel pipe outer side and / or inner side vicinity, and a root-like cement solidified body is made to the pile front-end | tip. While being formed, the solidified body of the fluidized solidifying material can be filled to a certain level inside the steel pipe. As a result, the closed bulb of the soil cement solidified body having an enlarged diameter can be reliably formed at the tip of the steel pile, and the supporting force is increased.
[Brief description of the drawings]
1A and 1B are a front view (upper view) and a bottom view (lower view), respectively, schematically showing an example of a steel pile 1 according to the present invention.
FIG. 2 is an external view of another embodiment of the steel pile of the present invention to which an injection nozzle and a vibro hammer are attached.
3 (A) to (I) show the presence or absence of protrusions 2 provided on the outer surface of the pile, the inner surface of the pile, or the inner and outer surfaces of the pile, and the spiral protrusions on the outer surface or the inner surface of the steel pile 1; It is a figure which shows the various modifications which combined.
FIGS. 4A to 4C are external views showing various embodiments of the injection nozzle. FIGS.
FIG. 5 is an external view showing another embodiment of the injection nozzle.
FIG. 6 is an external view showing still another embodiment of the injection nozzle.
FIG. 7 shows another embodiment of the steel pile, and is a schematic partial view near the tip of the steel pile.
FIG. 8 is a front view and a top view of a steel pile with protrusions according to the present invention.
FIG. 9 is a front view of a steel pile having trapezoidal protrusions.
FIG. 10 is a diagram showing an example of the arrangement of construction machines in the steel pile construction method of the present invention.
FIG. 11 is a process diagram for explaining each process of the steel pile construction method of the present invention.
FIG. 12 is a ground sectional view showing a state of a pile foundation (synthetic pile) formed by the steel pile construction method according to the present invention.
FIG. 13 is a view showing a steel pipe sheet pile that is an aggregate of steel pipes with protrusions.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Steel pile 2 Protrusion 3 Through-hole 4 Spiral protrusion 5a Introduction hole 5b Introduction notch 10 Steel pipe sheet pile 30 Injection nozzle 30a Injection hole 30b Injection nozzle shaft 31 Pipe hose 100 Steel pipe sheet pile foundation 200 Soil cement solidified body

Claims (11)

A steel pile driven using a vibro hammer and water or a fluidized solidifying material jet, in the direction of driving the steel pile provided on the outer surface of the pile or the inner surface of the pile or both the inner and outer surfaces of the pile near the tip of the steel pile A flat protrusion having a parallel plate surface, and a spiral protrusion provided on the outer surface of the pile or the inner surface of the pile or both the inner and outer surfaces of the pile at the portion to which the protrusion is attached, and the outer surface of the pile near the pile tip of the steel pile or A steel pile having one or more injection nozzles for injecting water or a fluidized solidifying material on the inner surface of the pile or on both the inner and outer sides of the pile.   The steel pile according to claim 1, wherein the spray nozzle is detachable.   3. The steel according to claim 1, wherein an injection direction by the injection nozzle is any direction between a driving direction of the steel pile and a direction perpendicular to the driving direction. Pile.   The steel pile according to any one of claims 1 to 3, wherein at least one of the injection nozzles has a rotary injection means for injecting while rotating.   The steel pile according to any one of claims 1 to 4, wherein at least one of the injection nozzles includes a plurality of injection holes having different injection directions.   The steel pile is provided with an introduction hole or an introduction notch for taking water or a fluidized solidified material injected from the injection nozzle attached to the outer surface of the steel pile into the inside of the steel pile. The steel pile according to any one of claims 1 to 5.   A construction method for driving the steel pile according to any one of claims 1 to 6 into the ground, wherein the steel pile is driven into the ground using a vibro hammer and spraying water or a fluidized solidifying material. Construction method. A first step of driving the steel pile to the support layer while spraying water;
A second step of pulling out the steel pile while injecting water or a fluidized solidifying material;
A third step of driving the steel pile again to the support layer while injecting water or a fluidized solidifying material,
The construction method for a steel pile according to claim 7, wherein the continuous second and third steps are performed one or more times.   The method for constructing a steel pile according to claim 8, wherein a driving depth of the steel pile in the third step is shallower than a driving depth of the steel pile in the first step.   In each of the first to third steps, the steel pile is driven or pulled out while changing either or both of the injection pressure or the injection amount of water or the fluidized solidifying material. The construction method of the steel pile in any one of.   The method for constructing a steel pile according to any one of claims 7 to 10, wherein after the driving of the steel pile is completed, the injection nozzle is pulled up while injecting a fluidized solidifying material.

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