JP5611264B2 - Precast block which becomes pillow concrete of pier - Google Patents

Description

  The present invention relates to a precast block which is assembled to a pile head of an existing steel pipe pile and becomes pillow concrete that supports a slab of a pier.

  There is a jetty constructed using steel pipe piles driven into the bottom of the water or water. In such a pier, a slab constituting the pier is supported by pillow concrete (a cradle) formed on the outside of a pile head of the steel pipe pile.

  The main problem to be solved by the present invention is that a jetty constructed using steel pipe piles can be constructed easily, appropriately and quickly by reducing work processes on site as much as possible. It is in.

In order to achieve the above object, according to the present invention, a pile head of an existing steel pipe pile constituting a pier has a spacer body that projects a precast block that becomes pillow concrete of a pier toward a central axis. A steel pipe configured to be received from below to a position where the upper end of the pile head hits the spacer body ;
A top surface located on the upper end of the steel pipe, a bottom surface located on the lower end of the steel pipe, and a side surface extending between the top surface and the bottom surface, and made of concrete formed outside the steel pipe. And a head
The side of the steel pipe below the bottom of the head has an injection part of the concrete for driving the concrete into the space formed between the steel pipe and the steel pipe pile after receiving the steel pipe pile into the steel pipe. Is formed,
The lower end of the steel pipe is formed with a concrete leakage preventing portion injected from the injection portion.

  According to this configuration, after allowing the pile head of the existing steel pipe pile to be received in the steel pipe of the precast block, by driving concrete into the space from the injection portion, the pile head of the precast block and the existing steel pipe pile The pillow concrete that supports the slab of the pier can be easily and appropriately provided outside the pile head of the existing steel pipe pile.

  The head may be provided with a connecting rod-like body so that a part of the head protrudes in the horizontal direction from the side surface. In such a case, using such connecting rod-like bodies, the adjacent precast blocks that are integrated with the pile heads of the existing steel pipe piles to become pillow concrete are connected in the horizontal direction, and desired. A jetty having a planar shape can be easily configured.

  According to the present invention, a jetty constructed using steel pipe piles can be easily, adequately and easily reduced by reducing the work process at the site as much as possible, especially by placing the concrete at the site to the minimum necessary. It can be built quickly.

Drawing 1 is a section lineblock diagram showing the state where the precast block concerning an embodiment was assembled on the pile head of the existing steel pipe pile. FIG. 2 is a plan view showing the state of FIG. FIG. 3 is a plan view of a jetty constructed using the precast block. FIG. 4 is a side view of the pier constructed using the precast block. FIG. 5 is a side view of the pier constructed using the precast block, and shows the pier from the right side of FIG.

  Hereinafter, a typical embodiment of the present invention will be described with reference to FIGS. The precast block C according to this embodiment is assembled to the pile head Pa of the existing steel pipe pile P, and becomes the pillow concrete Bb that supports the slab Ba of the pier B.

  In the illustrated example, the precast blocks C are assembled to the pile heads Pa of a plurality of existing steel pipe piles P, P... Driven into the bottom of the water or the waterside so as to form two rows, and are adjacent in each row. The precast blocks C are connected in the horizontal direction, and adjacent precast blocks C between the rows are connected in the horizontal direction, and the support portion of the slab Ba of the pier B is configured from these precast blocks C.

  Each precast block C has a steel pipe 1 and a head 2.

  The steel pipe 1 is configured to receive the pile head Pa of the existing steel pipe pile P from below. In the illustrated example, the steel pipe 1 has a cylindrical shape whose inner diameter is larger than the outer diameter of an existing steel pipe pile P having a cylindrical shape.

  A spacer body 10 protruding toward the central axis x of the steel pipe 1 is provided at a position in the middle of the steel pipe 1 in the vertical direction. In the illustrated example, the spacer body 10 has a plate shape in which one side portion 10a is fixed to the inner surface of the steel pipe 1, and is provided at four positions at intervals of 90 degrees in the direction of circling the central axis x. Yes. The protruding dimension of each spacer body 10 from the inner surface of the steel pipe 1 is equal, and the other side part 10d between the upper side part 10b and the lower side part 10c of the spacer body 10 approaches the lower side part 10c. The lever body 10 is inclined to reduce the plate width. The angle formed by the side portion 10d and the central axis x is the same in each spacer body 10. And in this embodiment, the steel pipe pile P is received in the steel pipe 1 up to the position where the upper end of the pile head Pa abuts against the inclined side part 10d of each spacer body 10 respectively. It has become. With the spacer body 10, the center axis x of the steel pipe 1 is made to coincide with the center axis x 'of the steel pipe pile P, and the top surface 20 of the head 2 described later formed on the outside of the steel pipe 1 is positioned horizontally. It is supposed to let you.

  At the lower end of the steel pipe 1, a leakage preventing portion 11 for the concrete 3 injected from an injection portion described later is formed. In the example shown in the figure, the leakage prevention part 11 is provided in the steel pipe 1 by fixing the outer peripheral part of the ring-shaped plate body 11 a to the lower end of the steel pipe 1. The inner diameter of the plate body 11a is substantially equal to the outer diameter of the steel pipe pile P. Reference numeral 12 in the figure denotes a bracket that supports the plate body 11a.

  On the other hand, the head 2 is made of concrete, and has a top surface 20 positioned on the upper end of the steel pipe 1, a bottom surface 21 positioned on the lower end of the steel pipe 1, and the top surface 20 and the bottom surface 21. It is formed on the outside of the steel pipe 1 with a side surface 22 extending therebetween. In other words, the head 2 is formed by placing concrete in the mold in a state where the upper end side of the steel pipe 1 is housed in the mold for forming the head 2. In the illustrated example, the top surface 20 of the head 2 is a surface orthogonal to the central axis x of the steel pipe 1.

  In the illustrated example, the head 2 includes a core portion 23 having a substantially square shape in a plan view and a branch portion 24 protruding from the core portion 23 in the horizontal direction. The top surface 20 of the core portion 23 and the top surface 20 of the branch portion 24 are the same surface. In the illustrated example, a precast block C ′ having a head portion 2 having a branch portion 24 on only one side of the core portion 23 and a precast having a head portion 2 having a branch portion 24 on both sides of the core portion 23, respectively. In combination with the block C ″, the supporting part of the slab Ba of the pier B is configured. That is, the former precast block C ′ is used at both ends of the supporting part, and the latter is provided in the middle of the supporting part. A precast block C ″ is used.

  In this embodiment, the head 2 is provided with a connecting rod-like body 25 so as to protrude partly from the side surface 22 in the horizontal direction. The connecting rod-like body 25 can be constituted by a steel bar or the like as an insert of the head 2 or a part of the reinforcing bar of the head 2. In the illustrated example, a connecting rod 25 protruding from the side 22 of one head 2 of an adjacent precast block C, and a connecting rod 25 protruding from the side 22 of one head 2 of an adjacent precast block C, Are connected via a sleeve body S. In this sleeve body S, the connecting rod-like body 25 of one precast block C is inserted from one end, and the connecting rod-like body 25 of the other precast block C is inserted from the other end, and then the grout is put inside. The material is filled. In the example shown in the drawing, a plurality of such connecting rod-like bodies 25 are provided at intervals between the connecting rod-like bodies 25 adjacent to each other in the horizontal direction. A row of rod-like bodies 25, 25... Is provided in two upper and lower stages. The gap y between adjacent precast blocks C is closed by connecting the connecting rod-like body 25 in this way, and then placing concrete (not shown), and the upper surface of the placed concrete is the top of the head 2. It is flush with the surface 20. Thereby, the adjacent precast blocks C and C, which are integrated with the pile head Pa of the existing steel pipe pile P and become the pillow concrete Bb, are connected in the horizontal direction by using the connecting rod 25. Thus, a pier B having a desired planar shape can be easily configured from a plurality of precast blocks C, C.

  Moreover, in this embodiment, the steel pipe 1 and the steel pipe pile P are placed on the side of the steel pipe 1 below the bottom surface 21 of the head 2 after the steel pipe pile P is received into the steel pipe 1. An injection portion of the concrete 3 for driving the concrete 3 into the space formed between the two is formed. (The place where the injection part is formed is indicated by reference numeral 13 in FIG. 1)

  After allowing the pile head Pa of the existing steel pipe pile P to be received in the steel pipe 1 of the precast block C, the concrete 3 is driven into the space from the injection portion, whereby the precast block C and the existing steel pipe pile P are The pile head Pa can be integrated and the pillow concrete Bb supporting the slab Ba of the pier B can be easily and appropriately provided outside the pile head Pa of the existing steel pipe pile P. In the example shown in the drawing, in order to enhance the unity, the stud is projected to the pile head Pa of the steel pipe pile P in the direction perpendicular to the outer surface of the pile head Pa before the concrete 3 is driven from the pouring portion. Bolts Pb are provided. The concrete poured from the pouring part typically uses a cement paste mixed with fine aggregate. In the illustrated example, the concrete 3 is driven up to a level reaching the tip of the pile head Pa of the steel pipe pile P.

B Pier P Steel pipe pile Pa Pile head 1 Steel pipe 11 Leakage prevention part 2 Head 20 Top face 21 Bottom face 22 Side face 3 Concrete

Claims (2)

A steel pipe having a spacer body protruding toward the central axis and configured to accept a pile head of an existing steel pipe pile constituting the pier from below to a position where the upper end of the pile head hits the spacer body ;
A top surface located on the upper end of the steel pipe, a bottom surface located on the lower end of the steel pipe, and a side surface extending between the top surface and the bottom surface, and made of concrete formed outside the steel pipe. And a head
The side of the steel pipe below the bottom of the head has an injection part of the concrete for driving the concrete into the space formed between the steel pipe and the steel pipe pile after receiving the steel pipe pile into the steel pipe. Is formed,
A precast block serving as pillow concrete for a pier, wherein a concrete leakage prevention portion injected from the injection portion is formed at a lower end of the steel pipe.   The precast block as a pillow concrete for a pier according to claim 1, wherein the head is provided with a connecting rod-like body so that a part of the head protrudes horizontally from the side surface.

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