JP6555623B2 - Concrete structure and construction method thereof - Google Patents

Description

  The present invention relates to a method for constructing a concrete structure that constitutes a structure such as a pier, and more particularly to a concrete structure in which precast concrete members adjacent to each other on the water or at a high place are connected by cast-in-place concrete and the construction method thereof. .

  In the construction of a pier, etc., a plurality of precast concrete precast concrete members constituting a concrete beam portion (hereinafter referred to as a concrete beam) and a slab (hereinafter referred to as a concrete slab) are manufactured in advance in an onshore factory or an onshore yard. After transporting it to the construction site and supporting the precast concrete member on the head of the steel pipe pile, cast-in-place concrete is placed between each precast concrete member and the two precast concrete members are connected to provide concrete beams, etc. A method for constructing a concrete structure is used (see, for example, Patent Document 1).

  At that time, in order to ensure the strength between the members, the precast concrete member is installed in such a manner that a plurality of reinforcing bars protruding from the end faces overlap each other, that is, to form a lap joint, and then the adjacent neighbor Temporary support for the formwork is placed between the matching precast concrete members, and after supporting the formwork, the cast-in-place concrete is placed in the formwork to connect the precast concrete members. It was.

JP 2001-288725 A

  However, in the conventional technology as described above, when the precast concrete members are connected, a scaffolding / supporting work is temporarily installed between the precast concrete members, and the temporary scaffolding / supporting work is used to assemble / disassemble the formwork ( It was necessary to carry out a series of operations such as demolding), arranging reinforcing bars and steel frames, placing concrete, and curing.

  The series of operations from the installation of the scaffolding support structure to the dismantling and removal had to be performed at sea, and there was a problem that it was affected by sea conditions and weather conditions.

  In addition, when the reinforcing bars protruding from the end face of the precast concrete member are lap joints, the precast concrete members are installed so as to be overlapped with each other.

  Furthermore, when installing a formwork in which the side plate and the bottom plate are integrated between precast concrete members without using support work, it is difficult to install the formwork by lifting the formwork with a crane because the rebar is in the way. There was a problem that there was.

  Then, in view of such a conventional problem, this invention aims at provision of the concrete structure which can install a formwork easily between precast concrete members, and its construction method, without using a special support work. It was made.

  The feature of the invention according to claim 1 for solving the conventional problems as described above is that a precast concrete member in which a plurality of reinforcing bars protrude from an end face is installed with a space between each other, and a form suspended by a suspension member is provided. In a method for constructing a concrete structure, which is installed in a gap formed between the two precast concrete members, and then casts cast-in-place concrete in the mold and connects the two precast concrete members. A suspension member passage gap is provided between the reinforcing bars protruding from the end face of the precast concrete member, and the suspension member is inserted into the suspension member passage gap from the side of the gap portion so that the mold is placed below the gap portion. After the movement, the formwork is installed in the gap, and then the reinforcing bars are connected by connecting bars straddling the reinforcing bars. .

  According to a second aspect of the present invention, in addition to the configuration of the first aspect, a shear reinforcing bar for bundling a plurality of reinforcing bars protruding from the end faces of the two precast concrete members is shifted to the end face side, and the connecting bars After connecting both the reinforcing bars through the joint, the shear reinforcing bars are moved to a portion where the reinforcing bars and the connecting bars overlap to bind the reinforcing bars, the connecting bars and the shear reinforcing bars.

  A feature of the invention described in claim 3 is that, in addition to the configuration of claim 1 or 2, the mold is lifted by a pair of suspension members respectively connected to the side plates.

  According to a fourth aspect of the present invention, in addition to the structure according to any one of the first to third aspects, a plurality of suspension members respectively connected to the bottom plate of the mold form at intervals in the insertion direction. .

  The feature of the invention described in claim 5 is that, in addition to the structure of any one of claims 1 to 4, the cast-in-place concrete placed between the precast concrete members and the formwork are integrated. .

  The feature of the invention described in claim 6 is that in a concrete structure in which precast concrete members installed at intervals are connected by cast-in-place concrete, between the reinforcing bars protruding from the end face of each precast concrete member. A suspension member passing gap formed, and a connecting bar straddling the reinforcing bars across the suspension member passing gap, and the reinforcing bars connected by the connecting bars are placed between the precast concrete members. It is to be placed in cast-in-place concrete.

  According to a seventh aspect of the present invention, in addition to the configuration of the sixth aspect, each of the precast concrete members includes a shear reinforcing bar that bundles a plurality of reinforcing bars protruding from the end face, and the shear reinforcing bar is provided on the end face side. And can be moved along the plurality of reinforcing bars.

  The construction method of a concrete structure according to the present invention can prevent contact between reinforcing bars protruding from the end face when each precast concrete member is installed by providing the configuration according to claim 1, and The formwork can be installed by crane without using special support work.

  In addition, in the present invention, by providing the configuration according to claim 2, the shear reinforcing bar does not become an obstacle when the precast concrete member and the formwork are installed, and the reinforcing bar and the connecting bar are firmly fastened after the installation. In addition, the main bar composed of the reinforcing bar and the connecting bar can be suitably restrained.

  Furthermore, in the present invention, by providing the configuration according to claim 3, the suspension member can be easily passed between the reinforcing bars when the formwork is installed.

  Furthermore, in the present invention, by having the configuration according to claim 4, even if it is long in one direction, such as a formwork used when constructing a flat slab, it can be lifted stably. In addition, the suspension member can be suitably inserted and passed through the suspension member passage gap.

  Moreover, in this invention, by providing the structure of Claim 5, removal of a formwork becomes unnecessary and it can aim at shortening of a work process.

  In addition, the concrete structure according to the present invention can be constructed with the structure of claims 6 to 7 so that a cast-in-place formwork can be installed without using a special support work. And sufficient strength of the cast-in-place concrete part can be secured.

It is a front view which shows an example of the structure using the construction method of the concrete structure which concerns on this invention. It is an AA line sectional view same as the above. It is a figure which shows the state between the precast concrete members installed in the construction method of the concrete structure based on this invention, Comprising: (a) is a side view, (b) is the same top view, (c) is the same BB FIG. (a) The expanded side view which shows the formwork used for the construction method of a concrete structure same as the above, (b) is the expanded sectional view. (A) is a side view which shows the state of the formwork hanging work in the construction method of a concrete structure same as the above, (b) is a BB line arrow directional view. It is a figure which shows the state which installed the formwork between the precast concrete members in the construction method of a concrete structure same as the above, Comprising: (a) is a side view, (b) is the same top view, (c) is the same BB FIG. It is a partial expanded sectional view which shows an example of the fixing method of a formwork same as the above. (A) is a side view which shows the state of the reinforcing bar connection operation | work in the construction method of a concrete structure same as the above, (b) is a BB line arrow directional view. It is an expanded sectional view which shows the state which cast the cast-in-place concrete in the construction method of a concrete structure same as the above. It is a front view which shows another example of the structure using the construction method of the concrete structure which concerns on this invention. It is a CC sectional view taken on the line. It is the elements on larger scale which show the state between the precast concrete members installed in the construction method of the concrete structure shown in FIG. 10, Comprising: (a) is a longitudinal cross-sectional view, (b) is the top view. It is a partial expanded sectional view which shows the state of a formwork installation work same as the above. It is a perspective view which shows the whole state same as the above. It is the elements on larger scale which show the state in which the formwork was installed in the construction method of a concrete structure same as the above, (a) is a longitudinal cross-sectional view, (b) is the top view. It is the elements on larger scale which show the state of the reinforcing bar connection operation | work in the construction method of a concrete structure same as the above, Comprising: (a) is a longitudinal cross-sectional view, (b) is the DD line arrow top view. It is the elements on larger scale which show the state of the placement work of the cast-in-place concrete in the construction method of a concrete structure same as the above, (a) is a longitudinal cross-sectional view, (b) is the top view.

  Next, embodiments of the concrete structure and the construction method thereof according to the present invention will be described based on the examples shown in FIGS.

  In addition, a present Example demonstrates the jetty which has the superstructure 3 made from concrete supported by the several pile 2, 2 ... casted in the water bottom part 1 as an example.

  This pier is composed of a plurality of piles 2, 2... Laid on the bottom 1, a reinforced concrete superstructure 3 supported by the piles 2, 2, and a floor slab 4 formed on the superstructure 3. It has. In addition, the code | symbol w in a figure is a water surface.

  The superstructure 3 joins precast concrete members 5, 5... Prefabricated in a factory or onshore yard to the pile heads of the respective piles 2, 2. A concrete frame (concrete structure) is formed by installing a formwork 7 in the part 6, placing cast-in-place concrete 8 in the formwork 7, and connecting the two precast concrete members 5 and 5 together. It has a shape.

  As shown in FIG. 2, each of the precast concrete members 5, 5 includes a base portion 5 a joined to the pile head of the pile 2 and a plurality of beam portions 5 b, 5 b extending from the base portion 5 a in the horizontal direction. They are formed in a plan view, a cross shape, an L shape, or a T shape.

  In each precast concrete member 5, 5 ..., a plurality of reinforcing bars 9, 9 ... are embedded in the beam portion 5b, and the tip side of each reinforcing bar 9, 9 ... projects in the horizontal direction from the end face of the beam portion 5b. .

  The projecting length from the end face of each reinforcing bar 9, 9... Projects in the gap 6 formed between the end faces of the precast concrete members 5 and 5 adjacent to each other with an interval (about 100 mm) in the direction between the end faces. The length is such that the length is adjusted, for example, a length that is ½ or less of the distance between the end faces.

  Further, as shown in FIG. 3, a plurality of shear reinforcing bars 11, 11 can be moved to the end surface side of the reinforcing bar group 10 including the plurality of reinforcing bars 9, 9,. It is installed in a state.

  The shear reinforcement bars 11 and 11 are formed in a rectangular ring shape and are fitted to the outside of the reinforcing bar group 10 composed of a plurality of reinforcing bars 9, 9, and restrain the outer periphery of the reinforcing bar group 10.

  When the precast concrete members 5, 5... Are joined to the pile heads of the piles 2, 2,..., As shown in FIG. .

  When the precast concrete members 5, 5... Are installed, the lengths of the reinforcing bars 9, 9... From the end faces of the precast concrete members 5 are such that the protruding lengths of the reinforcing bars 9, 9. The distance between the reinforcing bars 9, 9 is avoided, and a suspension member passing gap 12 is provided between the reinforcing bars 9, 9 protruding from the end face of each precast concrete member after installation. It is done.

  Next, the formwork 7 is transferred to the construction site by a crane ship or the like, the formwork 7 is held on the formwork hanger 13, and is lifted by the crane.

  As shown in FIG. 4, the mold 7 is formed in a U-shape comprising a bottom plate 14 and side plates 15 and 15 disposed on both sides of the bottom plate 14, and is disposed between both precast concrete members 5 and 5, A gap 6 is formed between the end faces of the precast concrete members 5 and 5.

  The side plates 15 and 15 are formed with insertion holes 17 through which the fixing bolts 16 are inserted at the four corners. As shown in FIG. By tightening to the insert metal fitting 18 embedded in the side surface portion of the beam portion 5a, the mold frame 7 can be fixed in a state of being spanned over the precast concrete members 5 and 5.

  Further, on both side plates 15, 15 of the mold 7, connecting tools 19, 19 such as eyebolts are fixed at the center of the upper edge, and a suspension member 20 made of a pair of wires connected to the connecting tools 19, 19, The mold 7 is suspended by the mold suspension 13 through 20.

  Further, the side plates 15 and 15 and the bottom plate 14 of the mold 7 are provided with a reinforcing bar body 23 composed of an inner reinforcing bar 21 and an outer reinforcing bar 22 arranged at an interval in the thickness direction. , 15 and the bottom plate 14 are buried with a certain concrete cover portion exposed.

Inner rebar 21 and the outer reinforcing bars 22 are connected by a corrugated reinforcing bar 24 to each other, by the reinforcement member 23 is disposed astride the mold 7 and place concrete 8, the mold 7 and place concrete 8 Are firmly connected to each other.

  Next, as shown in FIG. 5, the formwork 7 is suspended to a position lower than the precast concrete members 5, 5 at a position horizontally spaced from the gap 6 between the precast concrete members 5, 5.

  Then, while the suspension members 20 and 20 are inserted into the suspension member passage gap 12 from the side of the gap portion 6, the mold 7 is moved in the horizontal direction and is positioned directly below the gap portion 6.

  Thereafter, the mold 7 is raised by a crane, and the mold 7 is fitted to the outside of the gap 6 as shown in FIG. 6, and the side plates 15 and 15 of the mold 7 are precast concrete with fixing bolts 16. Fix to members 5 and 5.

  As a result, the mold 7 is supported between the precast concrete members 5 and 5, and the mold 7 can be installed between the precast concrete members 5 and 5 without using a special support. In this state, the suspension members 20 and 20 can be removed from the mold 7 and removed together with the mold suspension 13.

  Next, as shown in FIG. 8, the connecting bars 25 are disposed so as to straddle both reinforcing bars 9, 9... Projecting from the end surfaces of the adjacent precast concrete members 5, 5. , 9... And the connecting bars 25 are bound to connect both the reinforcing bars 9, 9.

  Further, the shear reinforcing bars 11, 11 that have been shifted to the end face side of the reinforcing bar group 10 are moved to a portion where the reinforcing bars 9, 9 ... and the connecting bars 25 overlap, and the reinforcing bars 9, 9 ..., the connecting bars 25, and The shear reinforcing bars 11, 11 are bound by a binding line or the like to form a main bar. Further, if necessary, a water stop treatment is applied to the joint between the mold 7 and each of the precast concrete members 5, 5.

  Next, as shown in FIG. 9, cast-in-place concrete 8 is placed in the mold 7, concrete is filled in the gap 6, and the cast-in-place concrete 8 is cured and solidified, thereby precast concrete member 5. , 5 are connected to form a concrete beam.

  In the concrete structure configured as described above and the construction method thereof, the formwork 7 can be installed while avoiding the reinforcing bars 9, 9 protruding from the end faces of the precast concrete members 5, 5. A sufficient strength of the cast-in-place concrete 8 portion can be ensured by connecting the reinforcing bars 9 with the connecting bars 25.

  In addition, since the formwork 7 is integrated with the cast-in-place concrete 8, it is left in the state fixed between both the precast concrete members 5 and 5 as it is.

  In the above-described embodiment, the concrete beam constituting the superstructure 3 of the pier has been described. However, the present invention is not limited to this, and may be applied to, for example, construction of a bridge or the like.

  Furthermore, the concrete structure is not limited to a concrete beam, and can be applied to the construction of a flat slab 30 as shown in FIGS. In addition, the same code | symbol is attached | subjected to the structure similar to the above-mentioned Example, and description is abbreviate | omitted.

  As shown in FIGS. 10 and 11, the flat slab 30 is formed by connecting the precast concrete members 31, 31 supported by the piles 2, 2,. Yes.

  Each precast concrete member 31, 31 is formed in a rectangular parallelepiped shape, and is joined to a pile head of each pile 2, 2,.

  Further, a plurality of reinforcing bars 35, 35... Are embedded in each precast concrete member 31, 31, and the front end side of each reinforcing bar 35, 35.

  The reinforcing bars 35, 35 are embedded in the precast concrete member 31 at the base end side, and the tip end side thereof protrudes in the horizontal direction with an interval in the vertical direction from the end face of the precast concrete member 31, 31.

  In installation of each precast concrete member 31,31, in the space | gap part 32 formed between the end surfaces of the precast concrete members 31,31 in which the rebars 35,35 ... mutually adjoin, a space | interval (about 100 mm) mutually in the direction between end surfaces. And a suspension member passing gap 36 is formed between the reinforcing bars 35.

  Next, the formwork 33 is transferred to the construction site by a crane ship or the like, the formwork 33 is held by the suspension frame 37, and is lifted by the crane.

  The mold frame 33 includes an elongated rectangular bottom plate 33a, is disposed between the two precast concrete members 31 and 31, and forms a gap 32 between the end surfaces of the precast concrete members 31 and 31.

  A plurality of couplers 39, 39... Are fixed to the bottom plate 33a at intervals in the insertion surface (longitudinal direction) with respect to the suspension member passage gap 36 on the center surface, and the suspension member 38 is suspended from the suspension frame 37. , 38... Can be connected to each other so that the long formwork 33 can be stably lifted in one direction.

  .. Are fixed to the bottom plate 33a also on both side portions in the direction between the precast concrete members 31 and 31 (short direction) with the central connector 39 interposed therebetween.

  Next, as shown in FIGS. 13 and 14, the mold frame 33 is moved to a position lower than the precast concrete members 31, 31 at a position horizontally spaced from the gap 32 between the precast concrete members 31, 31. Hanging down.

  .. Are inserted into the suspension member passing gap 36 from the side of the gap portion 32 while the mold 33 is moved in the horizontal direction so as to be positioned immediately below the gap portion 32. After that, the mold 33 is raised by a crane, and the mold 33 is fitted to the outside of the gap portion 32.

  Next, as shown in FIG. 15, the supporting beam members 40, 40 are laid between the upper surfaces of the adjacent precast concrete members 31, 31, and the cross member 41 is placed on the supporting beam members 40, 40. 41, and fixing beam members 42, 42 are installed on the cross members 41, 41.

  In this state, the lower ends of the support members 44 and 44 are connected to the connecting members 39 and 39 disposed on both sides of the bottom plate 33a of the mold 33, and the upper ends thereof are fixed to the fixing beam members 42 and 42. To fix.

  As a result, as shown in FIG. 15, the formwork 33 is supported between the precast concrete members 31 and 31 via the supporting beam members 40 and 40, the cross members 41 and 41, and the fixing beam members 42 and 42. Thus, the formwork 33 can be installed between the precast concrete members 31, 31 without using any special support work, and the suspension members 38, 38... Can be removed from the bottom plate 33 a of the formwork 33.

  Next, as shown in FIG. 16, the connecting bars 45 are disposed so as to straddle both the reinforcing bars 35, 35 protruding from the end surfaces of the adjacent precast concrete members 31, 31, and the reinforcing bars 35, 35 are bound by binding wires or the like. ... and the connecting bar 45 are bundled, and both the reinforcing bars 35, 35 ... adjacent in the direction between the two precast concrete members 31, 31 are connected.

  .. Are arranged on the upper and lower sides of the reinforcing bars 35, 35 in parallel with each other in the direction intersecting with the reinforcing bars 35, 35. The reinforcing bars 47 are arranged with shear reinforcing bars 47. , 35..., The connecting bars 45, the distribution bars 46, 46. Further, if necessary, a water stop treatment is applied to the joint between the mold 33 and each of the precast concrete members 31, 31.

  Next, as shown in FIG. 17, cast-in-place concrete 34 is placed in a mold 33, concrete is filled in the gap 32, and the cast-in-place concrete 34 is cured and solidified, thereby precast concrete member 31. , 31 are connected to form a flat slab 30 having a rectangular shape in plan view.

  Then, the supporting beam members 40, 40, the cross members 41, 41 and the fixing beam members 42, 42 are removed, and the operation is completed.

  In addition, the aspect of the reinforcing bars 35, 35... Is not limited to those exemplified in the above-described embodiments, and a desired shape can be adopted in consideration of the structure of the structure, the strength design between the members, and the like. .

  Further, the connecting bar 45 can adopt an appropriate shape by matching with the shape of each of the reinforcing bars 35, 35.

Furthermore, in the above-described embodiment, an example in which a so-called embedded formwork 33 is used and the formwork 33 is left without being removed has been described, but the form of the formwork 33 is not limited to the above-described embodiment, A normal mold 33 may be used and removed after the cast- in- place concrete 34 has solidified.

DESCRIPTION OF SYMBOLS 1 Water bottom part 2 Pile 3 Superstructure 4 Floor slab 5 Precast concrete member 6 Cavity part 7 Formwork 8 Cast-in-place concrete 9 Reinforcement 10 Reinforcement group 11 Shear reinforcement 12 Gap for passing through suspension member 13 Formwork lifting tool 14 Bottom plate 15 Side plate 16 Fixing bolt 17 Insertion hole 18 Insert metal fitting 19 Connecting tool 20 Hanging member 21 Reinforcing bar 22 Outer reinforcing bar 23 Reinforcing bar body 24 Corrugated reinforcing bar 25 Connecting bar 30 Flat slab 31 Precast concrete member 32 Gap 33 Formwork 34 Cast-in-place concrete 35 Reinforcing bar 36 Suspension member passage gap 37 Suspension frame 38 Suspension member 39 Connecting tool 40 Support beam material 41 Cross member 42 Fixing beam material 43 Fixing tool 44 Support member 45 Connecting bar 46 Power distribution bar 47 Shear reinforcement bar

Claims (7)

A precast concrete member with a plurality of reinforcing bars protruding from the end face is installed at a distance from each other, a mold frame lifted by a suspension member is installed in a gap formed between the two precast concrete members, and then the mold frame In the method for constructing a concrete structure in which cast-in-place concrete is placed and the two precast concrete members are connected,
A suspension member passage gap is provided between the reinforcing bars protruding from the end surfaces of the respective precast concrete members, and the suspension member is inserted into the suspension member passage gap from the side of the gap portion so that the mold frame is inserted into the gap. After moving to the subordinate, install the mold in the gap,
Thereafter, the reinforcing bars are connected by connecting bars straddling the reinforcing bars, and the concrete structure is constructed.   A shear reinforcement bar that bundles a plurality of reinforcing bars protruding from the end faces of the two precast concrete members is shifted to the end face side, and after connecting both the reinforcing bars via the connecting bars, the shear reinforcement bar is connected to the reinforcing bars. The method for constructing a concrete structure according to claim 1, wherein the reinforcing bars, the connecting bars, and the shear reinforcing bars are bundled by moving to a portion where the connecting bars overlap.   The method for constructing a concrete structure according to claim 1 or 2, wherein the formwork is lifted by a pair of suspension members respectively connected to the side plates.   The method for constructing a concrete structure according to any one of claims 1 to 3, wherein the concrete structure is lifted by a plurality of suspension members respectively connected to the bottom plate of the formwork at intervals in the insertion direction.   The method for constructing a concrete structure according to any one of claims 1 to 4, wherein the cast-in-place concrete placed between the precast concrete members and the formwork are integrated. In a concrete structure in which precast concrete members installed at intervals are connected by cast-in-place concrete,
A suspension member passing gap formed between the reinforcing bars protruding from the end face of each precast concrete member, and a connecting bar straddling the reinforcing bars across the suspension member passing gap, and connected by the connecting bars. A concrete structure characterized in that the two reinforcing bars are arranged in cast-in-place concrete placed between the precast concrete members. Each precast concrete member includes a shear reinforcement bar that bundles a plurality of reinforcing bars protruding from the end face,
The concrete structure according to claim 6, wherein the shear reinforcing bar can be moved toward the end face side and can be moved along the plurality of reinforcing bars.

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