JP2005264514A - Foundation slab structure of sea berth structure, and its construction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce temporary structures on the sea to shorten a construction period on the sea regarding a foundation slab of a sea berth structure. <P>SOLUTION: This foundation slab structure of the sea berth structure is provided with a half precast concrete slab 1 having a void space 2 surrounding pile heads of a plurality of foundation piles 6 so that peripheries of the pile heads are arranged in a state of being located in the void space 2, and cast-in-place concrete 11 placed around the pile heads in the void space 2. Beam members 3 are further provided joined to the pile heads and extended over the void space 2. The number of assemblies of the temporary structures on the sea for constructing the foundation slab can thereby be considerably reduced, and the construction period on the sea can be shortened. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a basic slab structure in a sea berth structure and a construction method thereof.

Conventionally, working platforms and dolphin-type structures (breasting dolphin, mooring dolphin, pipe bridge foundation, etc.) among sea berth structures have been slab beam or foundation slab driven in-situ after foundation piles have been placed on the seabed ground. It is customary that the concrete piles are integrated with the foundation piles by sea or underwater construction. In addition, as a pile head construction method, there is a pile head construction method for diagonal piles that uses a half-precast plate itself as a working scaffold, but can construct pile pile heads with no scaffolding and no support. Proposed. (For example, refer to Patent Document 1).
JP 2000-17642 A

  However, the above-mentioned in-situ concrete method requires large-scale support materials and formwork materials. In this method, the construction period at sea is long, and the influence on the construction due to the weather is great. In addition, even in the method in which the pile head is half-precasted, a connecting member for joining the pile head and the half-precast plate is required, and the sea berth structure itself in which a large vertical load and horizontal load act is constructed. Therefore, it is necessary to construct an upper structure such as a foundation slab separately by supporting the pile head.

  An object of the present invention is to reduce the number of temporary structures on the sea in the foundation slab of the sea berth structure and to shorten the construction period on the sea.

  In order to solve the above-described problems, the invention described in claim 1 includes, for example, a space 2 surrounding the pile heads of a plurality of foundation piles 6 in a foundation slab structure of a seaverse structure as shown in FIG. A half precast concrete slab 1 arranged in a state where the periphery of the pile head is located in the void 2 and a cast-in-place concrete 11 placed around the pile head in the void 2 It is characterized by providing.

  The invention according to claim 3 is, for example, as shown in FIGS. 2 to 5, in a foundation slab construction method for a sea berth structure, half precast concrete having a void 2 surrounding the pile heads of a plurality of foundation piles 6. Including a step of arranging the slab 1 in a state in which the periphery of the pile head is located in the space 2 and a step of placing a cast-in-place concrete 11 around the pile head in the space 2. It is characterized by.

  In this way, most of the foundation slab of the sea berth structure, that is, the portion other than the void 2 surrounding the pile heads of the plurality of foundation piles 6 is precast, and the half precast concrete slab 1 is used as a supporting material, mold By using only the empty space 2 surrounding the pile head as a frame material and using the cast-in-place concrete method, the assembly quantity of temporary structures on the sea to construct the foundation slab can be greatly reduced. This can shorten the construction period at sea.

  The invention according to claim 2 is the foundation slab structure of the sea berth structure according to claim 1, for example, as shown in FIG. 1, a beam joined to the pile head and suspended in the space 2. A material 3 is provided.

  According to a fourth aspect of the present invention, there is provided a method for constructing a foundation slab for a sea berth structure according to the third aspect of the present invention, for example, as shown in FIGS. It includes a step of joining the beam member 3 spanned to the place 2 to the pile head.

  As described above, the beam material 3 can be easily joined to the upper end of the pile head of the foundation pile 6 by passing the beam material 3 over the space 2 surrounding the pile head of the plurality of foundation piles 6. The half precast concrete slab 1 can be supported by the foundation pile 6, and the construction period on the sea can be shortened.

  The invention according to claim 5, for example, as shown in FIG. 6, in the foundation slab structure of the sea berth structure, a plurality of half precast concrete beams 12 joined to the pile heads of the plurality of foundation piles 15, A plurality of precast concrete slabs 13 placed along one side of the half precast concrete beam 12 in a shape surrounding the pile head and the half precast concrete beam 12, and around the pile head and It is characterized by comprising cast-in-place concrete 14 placed in a portion surrounded by the precast concrete slab 13 on the half precast concrete beam 12.

  The invention according to claim 6 is a process of joining a plurality of half precast concrete beams 12 to a pile head of a plurality of foundation piles 15 in a foundation slab construction method for a seaverse structure, for example, as shown in FIG. A step of placing a plurality of precast concrete slabs 13 around the pile head and surrounding the half precast concrete beam 12 along one side of the half precast concrete beam 12, and the pile It comprises a step of placing cast-in-place concrete 14 around the head and on a portion surrounded by the precast concrete slab 13 on the half precast concrete beam 12.

  Thus, the foundation slab of the sea berth structure is a beam slab structure, and most of the beams and slabs, that is, around the pile heads of the plurality of foundation piles 15 and on the half precast concrete beam 12 are surrounded by the precast concrete slab 13. The precast concrete beam 11 and the precast concrete slab 13 are used as a support material and a formwork material, and the precast concrete slab 13 around the pile head and on the half precast concrete beam 12 is precast. By constructing only the enclosed part using the cast-in-place concrete method, the assembly quantity of temporary structures on the sea to construct the foundation slab can be greatly reduced, and the construction period on the sea can be shortened. Can do.

  According to the invention described in claim 1 or 3, most of the foundation slab of the sea berth structure, that is, the portion other than the void surrounding the pile head of the plurality of foundation piles is precast, and this half precast concrete slab Is used as support material and formwork material, and only the void surrounding the pile head is constructed by the cast-in-place concrete method, which greatly increases the assembly quantity of temporary structures on the sea to construct the foundation slab. The construction period at sea can be shortened.

  According to the invention described in claim 2 or 4, the same effect as that of the invention described in claim 1 or 3 can be obtained, and the beam material is hung in the space surrounding the pile heads of the plurality of foundation piles. By passing, the beam material can be easily joined to the upper end of the pile head of the foundation pile, the half precast concrete slab can be supported by the foundation pile, and the construction period at sea can be shortened.

  According to the invention described in claim 5 or 6, the foundation slab of the sea berth structure is a beam slab structure, and most of the beams and slabs, that is, around the pile heads of a plurality of foundation piles and on the half precast concrete beam. Parts other than the part surrounded by the precast concrete slab are precast, and this half precast concrete beam and precast concrete slab are used as support material and formwork, and the precast concrete around the pile head and on the half precast concrete beam By constructing only the part surrounded by the slab by the cast-in-place concrete method, the assembly quantity of the temporary structure on the sea to construct the foundation slab can be greatly reduced, and the construction period on the sea is shortened. can do.

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.
[First Embodiment]
FIGS. 1A and 1B are a plan view and a cross-sectional view showing a basic slab structure of a seaverse structure according to a first embodiment of the present invention. This foundation slab is used for a pipe bridge foundation which is a dolphin-type structure of a sea berth structure, and includes a half precast concrete slab 1 having a cavity 2 surrounding a pile head of the foundation pile, and the cavity 2. And a cast-in-place concrete 11 (see FIG. 5) placed around the pile head in the space 2.

  Here, the half precast concrete slab 1 is made of reinforced concrete having a length of 10.5 m, a width of 7 m, and a height of 1.8 m, and has a rectangular parallelepiped shape. The space 2 surrounding the periphery of the pile head is 9.3 m in length, 3.1 m in width, 3.2 m in length, and 6.8 m in width so as to surround the periphery of the pile heads of the eight foundation piles 6. Are formed in a cross shape in which the two rectangles are overlapped at the center, and the cross section is formed to be 1.8 m which is the same as the height of the half precast concrete slab 1. The empty space 2 is finally filled with cast-in-place concrete 11. Further, a plurality of reinforcing bars 5 protrude from the side surface of the half precast concrete slab 1 on the side of the void 2 for fixing with the cast-in-place concrete 11.

  The beam 3 is H-shaped steel, and is hung on the side surface of the half precast concrete slab 1 on the side of the void 2 at a position where it is joined to the pile head of the foundation pile 6. An end portion of the beam member 3 is joined to the side surface of the half precast concrete slab 1 or is joined to a side portion of another beam member 3.

  Joining of the half precast concrete slab 1 and the beam member 3 is performed by a joint member 4. The joint member 4 is composed of a joint plate fixed to anchor bars embedded in the half precast concrete slab 1 and bolts for joining the two. The beam material 3 and the other beam material 3 are joined by welding, bolts, or the like.

  Next, with reference to FIGS. 2-6, the construction method of the foundation slab of the seaverse structure in this embodiment is demonstrated. The half precast concrete 1 in this embodiment has three voids 2 surrounding the pile head around the foundation pile 6. In addition, the reinforcement 5 which protrudes from the half precast concrete slab 1 is abbreviate | omitted in drawing.

  First, as shown in FIG. 2, the eight foundation piles 6 are driven into a predetermined location on the seabed so as to form one set of two piles, and the pile heads of the foundation piles 6 are pile heads of each pile. Project above the sea level so that the A work scaffold is installed around the pile head of the foundation pile 6, and the pile head of each foundation pile 6 is processed so that the pile head level of each foundation pile 6 becomes a predetermined height.

  Next, as shown in FIG. 3, a half precast concrete slab 1 is suspended by a wire 7 of a marine crane, and a plurality of beam members spanned by a worker 8 in a space 2 surrounding a pile head. 3 is joined to the upper end of the pile head of the corresponding foundation pile 6 to be fixed and supported on the foundation pile 6.

  Thereby, the said beam material 3 can be easily joined to the pile head upper end of the foundation pile 6, the half precast concrete slab 1 can be supported by the foundation pile 6, and the construction period on the sea is shortened. Can do.

  Moreover, in order to join the beam material 3 to the pile head of the foundation pile 6, the eight foundation piles 6 will be connected via the half precast concrete slab 1, and after the joining, the half precast concrete slab is connected. 1 and the foundation pile 6 can be united and it can be set as the stable structure.

  Here, the half precast concrete slab 1 is manufactured in advance on land near the offshore site. The half precast concrete slab 1 is manufactured by arranging the reinforcing bars of the precast part, installing the beam material 3 spanned in the void 2 surrounding the pile head in a predetermined position, assembling the formwork, This is done by placing concrete, curing it properly, and then removing the mold.

  The manufactured half precast concrete slab 1 is hung from the land with a crane or the like, loaded on a trolley, transported to an offshore site, and installed on the pile head of the foundation pile 6 as described above.

  Thereby, parallel work with other works types, such as pile driving, becomes possible, and the whole work period can be shortened. In addition, by reducing the work period on the sea where the influence of the weather is large, it is possible to reduce the process variation factors.

  Then, as shown in FIG. 4, an operator 8 gets on the half precast concrete slab, suspends scaffolding materials, formwork materials, reinforcing bars, etc. on the half precast concrete slab 1 with a crane, assembles the scaffold, and pile head The surrounding bottom formwork 10 and the reinforcing bar 9 are assembled. After that, as shown in FIG. 5, the cast-in-place concrete 11 is placed in the space 2 surrounding the pile head of the foundation pile 6 with a concrete mixer ship.

  Thereby, the assembly quantity of the temporary structure on the sea for constructing a foundation slab can be reduced significantly, and the construction period on the sea can be shortened. Furthermore, since the assembly quantity of the temporary structure is reduced and the remaining period of the temporary structure is shortened, it is possible to reduce the risk of outflow and scattering of the temporary structure due to stormy weather such as strong wind waves. And by making the foundation slab half-precast, the amount of concrete placed on the sea is reduced, so the amount of breathing water is reduced and the risk of seawater contamination can be reduced. Moreover, since the number of rebars assembled at sea is reduced and the rebar exposure period is shortened, the degree of rebar corrosion can be reduced.

  In addition, the shape and size of the precast concrete slab 1 can be appropriately changed depending on its use and the like, and the position, shape, size, and number of spaces 2 surrounding the pile head are also the number of foundation piles 6. Of course, it can be appropriately changed depending on the position, the placement angle, and the like. Further, the end portion of the beam member 3 may be directly embedded in the half precast concrete slab 1 instead of being joined by the joint member 4. In addition, it is needless to say that specific detailed structures and the like can be appropriately changed.

[Second Embodiment]
FIG. 6 is a plan view showing a basic slab structure of a seaverse structure according to a second embodiment of the present invention. This foundation slab is used as a working platform among the sea berth structures. The half precast concrete beam 12 joined to the pile heads of 48 foundation piles 15, and the surroundings of the pile heads and the half precast concrete beams 12 are used. Is surrounded by 43 precast concrete slabs 13 placed on one side of the half precast concrete beam 12, and around the pile head and on the half precast concrete beam 12 by the precast concrete slab 13. It consists of cast-in-place concrete 14 cast in the part.

  Here, the foundation slab has a beam slab structure, and has a rectangular shape in plan with a length of 40 m and a width of 30 m. The beams in the short side direction and the long side direction of the foundation slab are configured by connecting several half precast concrete beams 12 respectively.

  The half precast concrete beam 12 includes a precast concrete portion 16 and a steel beam 17 as shown in FIGS.

  As shown in FIG. 8, the precast concrete portion 16 is made of reinforced concrete having a cross section of 1200 mm in width and 1600 mm in height, and a concrete corbel for placing the precast concrete slab 13 on both sides of the upper portion of the precast concrete portion 16. 19 is provided. In addition, a plurality of reinforcing bars 18 protrude from the upper part of the half precast concrete beam 12 and the end side surface on the joint side with the other precast concrete beam 12 for fixing to the cast-in-place concrete 14.

  The steel beam 17 is H-shaped steel, and is embedded in the precast concrete portion 16 so as to expose a portion joined to the pile head of the foundation pile 15 from the precast concrete portion 16.

  The plurality of half precast concrete beams 12 are connected to each other by joining the exposed steel beams 17 by welding, bolts or the like.

  As shown in FIG. 9, the precast concrete slab 13 is made of a rectangular plate-shaped reinforced concrete and has a slab thickness of 400 mm. A plurality of reinforcing bars 20 protrude from the side surface of the precast concrete slab 13 for fixing with the cast-in-place concrete 14.

  Next, with reference to FIGS. 6-10, the construction method of the foundation slab of the seaverse structure in this embodiment is demonstrated.

  First, as shown in FIG. 6, 48 foundation piles 15 are driven into a predetermined location on the seabed so as to form one set of two piles, and the pile heads of the foundation piles 15 are pile heads of each pile. Is projected on the sea surface so that the shape becomes a predetermined lattice shape. A work scaffold is installed around the pile head of the foundation pile 15, and the pile head of each foundation pile 15 is processed so that the pile head level of each foundation pile 15 becomes a predetermined height.

  Next, the half precast concrete beam 12 is suspended with a wire of a marine crane, and the exposed steel beam 17 embedded in the half precast concrete beam 12 is joined to the upper end of the corresponding pile head of the foundation pile 15 to thereby obtain the foundation. It is fixed on the pile 15 and supported.

  Thereby, the steel beam 17 can be easily joined to the pile head upper end of the foundation pile 15, the half precast concrete beam 12 can be supported by the foundation pile 15, and the construction period on the sea can be shortened. it can.

  Then, the ends of the steel beam 17 embedded and exposed in the half precast concrete beam 12 are joined together, and the half precast concrete beams 12 are connected to form a beam of the foundation slab.

  Thereafter, the precast concrete slab 13 is placed along one side of the plurality of half precast concrete beams 12. By repeating these operations sequentially, a basic slab having a large area can be constructed.

  In the course of the above work, in order to join the steel beam 17 to the pile head of the foundation pile 15, a plurality of foundation piles 15 are connected via a plurality of half precast concrete beams 12, and after the joining In, the half precast concrete beam 12 and the foundation pile 15 can be united and can be set as the stable structure.

  Here, the half precast concrete beam 12 and the precast concrete slab 13 are manufactured in advance on the land near the offshore site. The half precast concrete beam 12 is manufactured by arranging the reinforcing bars 18 of the precast concrete part 16, installing the steel beam 17 at a predetermined position, forming a formwork, appropriately curing, and then demolding. Manufacture of the precast concrete slab 13 is performed by arranging reinforcing bars 20, forming a formwork, appropriately curing, and then demolding.

  The produced half precast concrete beam 12 and precast concrete slab 13 are suspended from the land by a crane or the like, loaded on a barge, transported to the offshore site, and installed on the pile head of the foundation pile 15 as described above. Is done.

  Thereby, parallel work with other works types, such as pile driving, becomes possible, and the whole work period can be shortened. In addition, by reducing the work period on the sea where the influence of the weather is large, it is possible to reduce the process variation factors.

  Then, the worker 8 gets on the half precast concrete beam 12 or the precast concrete slab 13, suspends scaffolding materials, formwork materials, reinforcing bars, etc. on the precast concrete slab with a crane, assembles the scaffold, Assemble the frame and rebar. Thereafter, as shown in FIG. 10, cast-in-place concrete 11 is placed around the top of the half precast concrete beam 12 and around the pile head with a concrete mixer ship.

  Thereby, the assembly quantity of the temporary structure on the sea for constructing a foundation slab can be reduced significantly, and the construction period on the sea can be shortened. Furthermore, since the assembly quantity of the temporary structure is reduced and the remaining period of the temporary structure is shortened, it is possible to reduce the risk of outflow and scattering of the temporary structure due to stormy weather such as strong wind waves. And by making the foundation slab half-precast, the amount of concrete placed on the sea is reduced, so the amount of breathing water is reduced and the risk of seawater contamination can be reduced. Moreover, since the number of rebars assembled at sea is reduced and the rebar exposure period is shortened, the degree of rebar corrosion can be reduced.

  In the above embodiment, in FIG. 7, the half precast concrete beam 12 is composed of five precast concrete portions 16 and the steel beam 17 embedded and exposed in this, but it is limited to this. Instead, it can be constituted by an arbitrary number of precast concrete portions 16 and steel beams 17. In addition, the shape and size of the precast concrete part 16 can be appropriately changed according to the use of the foundation slab, the number of the foundation piles 15, the position, the interval, the placing angle, etc. Of course, it can be changed appropriately.

It is a figure which shows the basic slab structure of the seaverse structure in 1st Embodiment, (a) is a top view, (b) is sectional drawing. In 1st Embodiment, it is a figure which shows the step which has laid the foundation pile and is processing the pile head, (a) is a top view, (b) is sectional drawing. In 1st Embodiment, it is a figure which shows the step which joined the precast concrete slab to the pile head, (a) is a top view, (b) is sectional drawing. In 1st Embodiment, it is a figure which shows the step which has assembled the formwork and the reinforcing bar, (a) is a top view, (b) is sectional drawing. In 1st Embodiment, it is a figure which shows the step which has cast cast-in-place concrete, (a) is a top view, (b) is sectional drawing. It is a top view which shows the basic slab structure of the sea berth structure in 2nd Embodiment. It is a longitudinal cross-sectional view which shows the half precast concrete beam in 2nd Embodiment. It is a cross-sectional view which shows the half precast concrete beam in 2nd Embodiment. It is a figure which shows the precast concrete slab in 2nd Embodiment, (a) is a top view, (b) is sectional drawing. In 2nd Embodiment, it is a figure which shows the step which has cast cast-in-place concrete, (a) is a top view, (b) is sectional drawing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Half precast concrete slab 2 The space surrounding a pile head 3 Beam material 4 Joint member 5, 9, 18, 20 Reinforcement 6, 15 Foundation pile 7 Marine crane wire 8, 21 Worker 10 Bottom formwork 11, 14 Cast-in-place concrete 12 Half-precast concrete beam 13 Precast concrete slab 16 Precast concrete part 17 Steel beam 19 Concrete corbel

Claims (6)

A half precast concrete slab having a space surrounding a pile head of a plurality of foundation piles, and arranged around the pile head in a state of being located in the space;
A foundation slab structure of a sea berth structure comprising cast-in-place concrete cast around the pile head in the void.   The foundation slab structure of the sea berth structure according to claim 1, further comprising a beam member joined to the pile head and suspended in the space. A step of arranging a half precast concrete slab having a space surrounding a pile head of a plurality of foundation piles in a state where the periphery of the pile head is located in the space;
And a step of placing cast-in-place concrete around the pile head in the void.   The foundation slab construction of a sea berth structure according to claim 3, further comprising a step of joining a beam material spanned in the void to the pile head prior to the step of placing the cast-in-place concrete. Method. Multiple half precast concrete beams joined to the pile heads of multiple foundation piles;
A plurality of precast concrete slabs placed along one side of the half precast concrete beam in a shape surrounding the pile head and the half precast concrete beam,
A foundation slab structure of a sea berth structure comprising cast-in-place concrete placed around the pile head and on the half precast concrete beam and surrounded by the precast concrete slab. Joining a plurality of half precast concrete beams to the pile heads of a plurality of foundation piles;
Placing a plurality of precast concrete slabs around the pile head and surrounding the half precast concrete beam along one side of the half precast concrete beam; and
A foundation slab construction method for a sea berth structure, comprising a step of placing cast-in-place concrete in a portion surrounded by the precast concrete slab around the pile head and on the half precast concrete beam.

Images