JP5067931B2 - Steel pipe pile tip extension structure and steel pipe pile tip extension construction method - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a steel pipe pile tip extension structure and a steel pipe pile tip extension construction method for preventing uneven settlement of buildings, civil engineering structures, and the like.

  The buildings and civil engineering structures may sink differently due to differences in the position of the center of gravity of the buildings and civil engineering structures and the layer thickness of the soft ground. Conventionally, as a measure for preventing the uneven settlement of buildings and civil engineering structures, a construction in which a pile is driven to a hard ground underground and supported by the pile has been performed. Steel pipe piles are generally used for non-settled subsidence, and the steel pipe piles have a tip, a bare tube, a tapered tube, or a spiral wing tube, and the construction method counteracts the weight of the building or civil engineering structure itself. A press-fitting method using a hydraulic jack with force or swiveling is adopted.

  In addition, it has a pointed head at the tip of the driven pile or tubular pile, and by pushing against the guide surface of the pointed head and guiding it, the legs and reinforcing members are spread radially to increase the support force and stabilize Techniques for obtaining the supported piles and tubular piles are also disclosed and publicly known. (For example, see Patent Document 1 and Patent Document 2)

JP-A-61-221414 JP 2003-193465 A

  However, when the tip shape is a bare tube or a tapered tube, the tip may be crushed when driven, or it may be re-sinked after construction to prevent uneven settlement, and if the driving depth is relatively shallow or soft ground, When the driving depth is deep or when driving into hard ground, there is a problem that the main body of the building or civil engineering structure is lifted by press-fitting a hydraulic jack, and when the tip shape is a spiral blade, driving by turning Stable support by the effect and friction effect can be obtained, but there is a problem that the surrounding ground is disturbed.

In addition, the techniques described in Patent Document 1 and Patent Document 2 are effective in preventing uneven settlement, but have a problem that is difficult to apply in the case of construction in a stable and deep position at an arbitrary depth.
It is an object of the present invention to provide a steel pipe pile tip extension structure and a steel pipe pile tip extension construction method made in view of the problems described above.

In order to achieve the above-mentioned subject, it is set as the tip expansion structure of a steel pipe pile and the tip expansion construction method of a steel pipe pile which take the means as described below. That is,
(1) A cylindrical body having a cutting edge formed at the tip thereof is fitted and fixed to the outer diameter portion of the steel pipe having a solid conical or pyramidal pointed tip at the tip, and the cylindrical body is fitted and fixed. The steel pipe incorporates an expansion member and a press-fitting member, each of which has a plurality of claw blades formed in a slanting downward radial direction with a V-shaped rising angle. The V-shaped rising angle of the expansion member is expanded by the press-fitting member. By doing so, it is set as the structure which expands the said several nail | claw blade radially diagonally downward to the said cylinder body, The tip expansion structure of the steel pipe pile characterized by the above-mentioned.
(2) The steel pipe according to (1) above, wherein a wedge-shaped press-fitting member indexed to fit the positions of the plurality of claw blades is fitted in a steel pipe with a solid pointed member. Pile tip extension structure .

(3) A steel pipe with a cutting edge formed at the tip is fitted to the outer diameter of the tip of the steel pipe with a cone or pyramid-shaped solid pointed member at the tip, and the inside of the steel pipe fitted with the cylinder In addition, a steel pipe of the same diameter cut to a fixed length is formed on the upper surface of a steel pipe which is built up with an expansion member and a press-fitting member, each of which is formed with a plurality of claw blades radially inclined at a V-shaped rising angle. After driving to a predetermined depth while adding, the V-shaped rising angle of the expansion member is expanded by a press-fitting member, and the extension member's claw blades are radially extended outwardly from the cylindrical body and installed. A method for extending the tip of a steel pipe pile.
(4) It is provided with a driving member for hitting and driving the back surface of the pointed member in the steel pipe, and dropping the monken weight to the upper end of the driving member and driving it to a predetermined depth while hitting it. The method for expanding the tip of a steel pipe pile according to item (3) above, which is characterized.
(5) At the upper end of the wedge-shaped press-fitting member indexed to the position of the nail blade of the expansion member formed radially, the monken weight is dropped to press the press-fitting member, and the V-shaped rising angle of the expansion member is set. The method for expanding the tip of a steel pipe pile according to the above item ( 3) or (4), wherein the method is expanded.
(6) the crushed stones was the charging into the steel tube, to press the pressed member pressurizes the the charging has been crushed stone, item (3), characterized in that for diverging V-shaped rising angle of the extension member steel pipe according Pile tip extension construction method.
(7) The method for extending the tip of a steel pipe pile according to (6) above, wherein the upper end portion of the steel pipe pile driven into a predetermined depth is supported by the lower surface of the foundation of the building and the civil engineering structure.

According to the present invention in which the above means is taken, the following effects can be obtained. That is,
(1) The tip of the steel pipe pile is a solid conical or pyramid-shaped pointed member, and a cylindrical body having a cutting edge is fitted to the outer diameter portion, so that the steel pipe pile is stable without being displaced. This is effective in preventing the tip from being crushed.
(2) By striking the hammering member in the steel pipe stepped on the back surface of the pointed member by dropping the monken weight, the buckling of the steel pipe is prevented and it is effective in driving deeply.
(3) For expanding the tip at an arbitrary depth position by dropping the monken weight, expanding the V-shaped rising angle of the expansion member in the steel pipe, and expanding the claw blade of the expansion member There is an effect.
(4) By inserting and installing a steel pipe of the same diameter cut to a fixed length, it is effective for driving to an arbitrary depth position, and handling of the steel pipe is performed by cutting to a fixed length. It becomes easy.
(5) Insert the crushed stone into the steel pipe, and pressurize the inserted crushed stone from above to support the upper end of the steel pipe pile on the lower surface of the foundation of a building or civil engineering structure. The tip can be extended at depth.

  BEST MODE FOR CARRYING OUT THE INVENTION The best mode for carrying out the present invention will be described in detail in the following embodiments with reference to the drawings showing the embodiments. The drawings showing the embodiments are the best mode for carrying out the present invention, but the present invention is not necessarily limited thereto.

  1A and 1B are drawings showing an embodiment of a steel pipe pile tip extension structure according to the present invention, in which FIG. 1A is a longitudinal sectional view thereof, and FIG. 1B is a plan view taken along line AA in FIG. . As shown in the drawing, the steel pipe pile tip extension structure according to the present invention has a cutting edge formed at the tip outer diameter portion of a steel pipe 2 with a conical or pyramid-shaped solid pointed member 1 attached to the tip. An expansion member in which a cylindrical body 3 is fitted, and a plurality of claw blades 4, 4,... Are formed radially in a diagonally downward direction in a steel pipe 2 fitted with the cylindrical body at a V-shaped rising angle. 5 and a press-fitting member 6, and by expanding the V-shaped rising angle T of the expansion member 5 by press-fitting the press-fitting member 6, the plurality of claw blades 4, 4,. -It is the structure which expands diagonally downward radially outside the cylinder 3.

  When the steel pipe 2 is a round steel pipe, the pointed member 1 attached to the tip of the steel pipe 2 is sharpened in a conical shape, and when the steel pipe 2 is a square steel pipe, the tip of the steel pipe 2 is sharpened in a pyramid shape. The cylindrical body 3 is fitted on the outer diameter portion of the tip and fixed by welding or the like. A concave hole 1a for supporting the lower end of the V-shaped rising portion of the expansion member 5 at the center is provided on the back surface of the pointed member 1, and the claw blades 4 of the expansion member 5 are provided in the steel pipe 2 and the cylindrical body 3. .. is provided with a window 3a for projecting and expanding radially outwardly from the cylinder 3, and a cutting edge 3b is provided at the tip of the cylinder 3 so that it can be driven in a stable state without displacement. It is.

  The pointed member 1 is processed innocently using a relatively hard steel material, and the tip end is rounded to prevent crushing, and the cylindrical body 3 is also made of a relatively hard steel pipe or the like. It is desirable to form a sharp-edged cutting edge 3b at the tip, and it is desirable that the expansion member 5 is formed by processing with a steel material that is hard to break and is tough.

  The extension member 5 has a shape as shown in FIG. 3, and the claw blades 4, 4,... Are formed by being equally divided into four diagonally downward radial directions in this embodiment. However, it is not limited to this. What is indexed radially in diagonally downward directions in approximately 3 to 8 directions is preferably used.

  The press-fitting portion insertion member 6 is a wedge-shaped press-fitting member formed in accordance with the positions of the plurality of claw blades 4, 4,. As shown in FIG. 4, the press-fitting member 6 for expanding and expanding the expansion members 5 (shown in FIG. 3) formed by radially dividing the blades 4, 4,. It becomes the shape which has the wedge shape 6a, 6a, ... indexed in the cross shape.

.. Are inserted between the claw blades of the expansion member 5 and between the claw blades of the press-fitting member 6 and between the wedge portions of the press-fitting member 6. The cylindrical member 3 and the steel pipe 2 are driven by striking the back surface of the sharp member 1 and driving the sharp member 1. The driving member 7 has legs 7a, 7a,... As shown in FIG. 5 and has a shape having an inner diameter hole 7b. A tip portion such as a monken weight is passed through the inner diameter hole 7b with a small diameter. 6 is hit and pressed, and the expansion member 5 is expanded to expand the claw blades 4, 4,.
The press-fitting member 6 inserts crushed stone or the like into the steel pipe 2 in addition to striking with the monken weight, and presses the press-fitted member 6 by pressing the inserted crushed stone or the like with a hydraulic jack or the like from above. And the method of expanding the nail | claw blade 4,4, ... radially by expanding an expansion member is also performed. In this case, the driving member 7 needs to be removed from the steel pipe 2 in advance.

Construction example 1

  FIG. 6 shows an example of driving a steel pipe pile in which a rod-shaped monken weight 10 suspended by a wire 9 is dropped into the steel pipe by the monken winch 8 and the steel pipe cut into a fixed length is driven while being added. Is an example of expanding the tip of a steel pipe pile driven into a predetermined position.

  In FIG. 6, when the monken weight 10 suspended by the wire 9 is dropped, the upper end surface of the driving member 7 is hit, and the back surface of the pointed member 1 is hit by the legs 7a, 7a,. Then, the pointed member 1 is driven into the ground, and the cutting blade 3b of the cylindrical body 3 is driven in so that the steel pipe 2 is lowered downward. When the cutting edge 3b of the cylindrical body 3 is driven, a positional shift is prevented and a stable driving can be performed straight.

  While the steel pipes 2A, 2A,... Having the same diameter are added to the upper ends of the steel pipes that have been driven downward by welding 2a, 2a,..., The monken weight 10 is repeatedly dropped and driven to a predetermined depth. The steel pipe 2A to be added is a standard material roughly cut to about 1 to 3 m. In the case of driving by dropping the monken weight 10 suspended by a monken winch or the like, a long standard material of about 2 to 3 m is used. Is good.

After driving to a predetermined depth as shown in FIG. 6, a tip member 10 a is attached to the tip of the monken weight 10 as shown in FIG. 7, and the striking diameter portion of the tip member is the inner diameter of the driving member 7. The claw blades 4, 4,... Of the expansion member 5 expand radially outward in a diagonally downward direction by pressing the upper surface of the press-fitting member 6 with a small diameter so as to pass the hole 7 b. Is done.
When the upper surface of the press-fitting member 6 is struck by being hit and pressed, the upper end of the steel pipe is supported.

In the state where the claw blades 4, 4,... Of the expansion member 5 are expanded, the monken weight 10 and the tip member 10a suspended by the wire 9 are wound up with a monken winch or the like and taken out.
The press-fitting member 6 and the driving member 7 may be built in the steel pipe 2 as they are. However, as shown in FIG. 8, the magnet 10b is attached to the tip member 10a attached to the tip of the monken weight 10, and the press-fitting member 6 By adsorbing the upper surface and pulling up the monken weight 10, the lower surface of the head of the driving member 7 is hooked on the outer periphery of the upper surface of the pressing member 6, and the pressing member 6 and the driving member 7 can be simultaneously pulled up and taken out.

  As described above, the concrete is poured into the steel pipe in a state where the claw blades 4, 4,... Of the expansion member 5 are obliquely expanded radially downward to the outside of the cylinder 3, and the cylinders from the windows 3a, 3a The claw blades 4, 4,... Are hardened with concrete to allow strong support such as in soft ground. The upper ends of the steel pipes 2A,... Are fixed to the lower surface of a foundation such as a building or a civil engineering structure via a support column (not shown).

Construction example 2

FIG. 9 is an example of driving a steel pipe pile when a hydraulic jack is installed and driven on the lower surface of a foundation such as a building, and FIG. 10 is an example of a tip extension of the steel pipe pile driven to a predetermined position with a hydraulic jack.
As shown in FIG. 9, a hydraulic jack 12 is installed on the lower surface of a foundation 11 such as a building, and the upper end of the added steel pipe 2 </ b> A is pressed with a pressure plate 13 attached to the push rod end of the hydraulic jack 12. The steel pipe 2A to be added has the same diameter as that of the steel pipe 2 and is preferably relatively short compared to the case of the construction example 1, and is preferably a standard length material of about 1 to 1.5 m.

  After driving into a predetermined depth as shown in FIG. 9, the crushed stones 14,... Are inserted into the steel pipe as shown in FIG. The press-fitting member 6 is pressed by pressurizing the upper end portion of the crushed stone 14 inserted by the pressurizing plate 13a attached to the push rod end of the hydraulic jack 12 in a state of being supported by and fixed to the lower surface of the foundation 11. Then, the claw blades 4, 4,... Of the expansion member 5 are expanded radially outward and obliquely downward.

  By being constructed as described above, it is possible to drive a steel pipe pile that is deep and straight, and to extend the tip of the steel pipe pile at an arbitrary depth position.

It is drawing which shows the Example of the tip expansion structure of the steel pipe pile concerning this invention, (A) is the longitudinal cross-sectional view, (B) is an AA arrow top view of (A). It is the longitudinal cross-sectional view which expanded the tip expansion structure of the steel pipe pile concerning this invention. It is a perspective view which shows embodiment of an expansion member. It is a perspective view which shows embodiment of a press-fit member. It is a perspective view showing an embodiment of a driving member. It is a longitudinal cross-sectional view which shows the driving example of the steel pipe pile by the monken weight suspended by the monken winch. It is a longitudinal cross-sectional view which shows the example of the front-end | tip expansion of the steel pipe pile by the example of driving | running of a monken weight. It is a longitudinal cross-sectional view which shows the extraction example of a press-fitting member and a driving member. It is a longitudinal cross-sectional view which shows the driving example of the steel pipe pile by a hydraulic jack. It is a longitudinal section showing an example of tip extension of a steel pipe pile by pressurization of crushed stone with a hydraulic jack.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pointed member 1a Recessed hole 2,2A Steel pipe 3 Tube 3a Window 3b Cutting blade 4 Claw blade 5 Expansion member 6 Press-fitting member 6a Wedge part 7 Driving member 7a Leg 7b Inner diameter hole 8 Monken winch 9 Wire 10 Monken weight 10a Tip member 10b Magnet 11 Foundation 12 Hydraulic jack 13, 13a Pressure plate 14 Crushed stone 15 Support strut frame

Claims (7)

  A cylindrical body with a cutting edge formed at the tip is fitted into the outer diameter portion of the steel pipe with a conical or pyramid-shaped solid pointed member at the tip. The expansion member having a plurality of claw blades formed in a diagonally downward radial direction and a press-fitting member are built in at a character rising angle, and the V-shaped rising angle of the expansion member is expanded by the press-fitting member. A structure for extending the tip of a steel pipe pile, wherein a plurality of claw blades are radially extended outwardly from the cylinder.   The steel pipe pile tip extension structure according to claim 1, wherein a wedge-shaped press-fitting member indexed to fit the positions of the plurality of claw blades is fitted into a steel pipe with a solid pointed member. .   A cylindrical body with a cutting edge formed at the tip is fitted into the outer diameter portion of the steel pipe with a conical or pyramid-shaped solid pointed member at the tip. A steel pipe of the same diameter cut to a predetermined length is added to the upper end of a steel pipe that is built up with an expansion member and press-fitting members that are formed with a plurality of claw blades in a diagonally downward direction by rising at a character rising angle. And then extending the V-shaped rising angle of the expansion member with a press-fitting member and extending the claw blade of the expansion member radially outwardly to the outside of the cylinder. Tip extension construction method for steel pipe piles. The steel pipe is provided with a driving member for hitting and driving the back surface of the pointed member, and a monken weight is dropped to the upper end of the driving member and driven to a predetermined depth. The method for extending the tip of a steel pipe pile according to claim 3 . A monken weight is dropped on the upper end of the wedge-shaped press-fitting member that is indexed to the position of the nail blade of the expansion member formed radially, and the press-fitting member is pressed to widen the V-shaped rising angle of the expansion member. The steel pipe pile tip extension construction method according to claim 3 or claim 4, wherein The tip extension of a steel pipe pile according to claim 3 , wherein crushed stone is inserted into the steel pipe, the inserted crushed stone is pressed to press the press-fitting member, and the V-shaped rising angle of the expansion member is expanded. Construction method. The steel pipe pile tip extension construction method according to claim 6 , wherein the upper end portion of the steel pipe pile driven into a predetermined depth is supported by the lower surface of the foundation of the building and the civil engineering structure.

Images