JP2006193985A - Concrete construction joint method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a concrete construction joint method for coping with preceding placing of concrete having high fluidity, dispensing with construction of a vertical joint, and dispensing with removal of a concrete stopper to joint concrete on a vertical joint face. <P>SOLUTION: In this concrete construction joint method, a partition plate 10A is first manufactured. The partition plate is composed of a steel plate, a reinforcing bar insertion hole 14 is formed at a position corresponding to a reinforcing bar 18 to be arranged, and a protruding bar pattern 16 capable of transmitting shearing force among each of its both faces and concrete to be placed in contact with the faces is formed on each of both faces. Next, the partition plate is positioned at a position for forming the vertical joint face and a reinforcing bar is inserted into the reinforcing bar insertion hole of the partition plate to assemble the reinforcing bars. A form 20 is constructed, precedingly placing concrete is placed to come into contact with a face on one side of the partition plate, and posteriorly placing concrete is placed to come into contact with a face on the other side of the partition plate. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a concrete joining method, and more particularly to a concrete joining method for joining concrete on a vertical joining surface in reinforced concrete work.

  In reinforced concrete construction, in order to pass concrete on the vertical transfer surface, concrete stops are required to dam the concrete (advanced concrete) placed first in the formwork at the position where the vertical transfer surface is formed. It becomes. The simplest way to do this is to use a partition plate made of plywood for formwork as a concrete stop. However, the plywood partition plate must be removed after placing the precast concrete, and the vertical joint surface formed by the precast concrete using the plywood partition plate is a flat surface. For this reason, the vertical joint surface is roughened or a shear cotter is provided so that the shearing force is sufficiently transmitted between the pre-cast concrete and the post-cast concrete. Further, if necessary, the rough vertical surface is wetted with water or impregnated with an appropriate agent. Therefore, this method is inevitably expensive.

  As a lower cost method, there is a method of using a concrete stopper formed of a lath net such as expanded metal, and this method is widely adopted. In this method, since the shearing force is sufficiently transmitted between the pre-cast concrete and the post-cast concrete through the irregularities of the concrete extruded from the mesh of the lath mesh or the irregularities of the lath mesh itself, It is not necessary to make the surface rough, and if not so many days have passed since the placement of the pre-cast concrete, it is not necessary to perform the operation such as hydration. Further, the lath net used as a concrete stopper does not need to be removed, and post-cast concrete can be directly placed and buried in the concrete, which is also advantageous in terms of cost. However, it is possible to dam up with lath nets only for concrete with relatively low fluidity, such as conventional concrete with slump management, for example, with high fluidity concrete such as ultra-high strength concrete. This method cannot be applied because the mortar portion of concrete leaks through the mesh.

In addition to this, many patent literatures disclose various concrete fastening methods for joining concrete with a vertical joining surface. Specific examples thereof are disclosed in the following patent documents 1 and 2. There are things.
JP-A-08-135246 JP 2000-027439 A

  In a reinforced concrete building or the like, the concrete strength required for design usually differs depending on the part of the building. Therefore, if necessary, concrete having different strengths is divided for each part, so that the amount of high-priced high-strength concrete used can be limited, which is advantageous in terms of cost. However, when it is necessary to pre-cast high-strength concrete with high fluidity when placing concrete, concrete stops made of lath nets cannot be used. There was a problem of being forced to adopt this method.

  The present invention has been made in view of such circumstances, and an object of the present invention is a concrete jointing method for joining concrete on a vertical joint surface in reinforced concrete work, and pre-casting highly fluid concrete. It is possible to cope with the case, and it is necessary to provide a concrete joining method that is reliable and cost-effective, which does not require the construction of vertical joints and does not require the removal of concrete stops. .

  In order to achieve the above object, a concrete jointing method for joining concrete with a vertical joint surface in a reinforced concrete construction according to the present invention is made of a metal plate or a high-strength resin plate, and corresponds to the vertical joint surface of concrete. Reinforcing bar insertion hole is formed at a position corresponding to the reinforcing bar to be laid, and has a shape and a dimension including the vertical joining surface of the shape and dimension or concrete, and is placed in contact with the surface on each of both surfaces. Producing a partition plate formed with protrusions or irregularities capable of transmitting shearing force with concrete, so that the partition plate is positioned at a position where a vertical joint surface is formed, and the partition plate Assemble the reinforcing bars by inserting the reinforcing bars into the reinforcing bar insertion holes, lay the formwork, place the precast concrete so as to contact one surface of the partition plate, And Da設 the post-deposited concrete in contact with the surface of the square, and performs dismantling of the mold after curing of the concrete.

  According to the present invention, even when a highly fluid concrete such as ultra-high strength concrete is struck first, the concrete can be appropriately stopped by the partition plate made of a plate material. Further, since the shearing force can be transmitted to the concrete by the protrusions or the uneven portions formed on both surfaces of the partition plate, it is not necessary to construct a vertical joint when placing the post-cast concrete. Furthermore, since the partition plate is embedded in the concrete by the placement of post-cast concrete, it is not necessary to remove the concrete stopper, thereby achieving a concrete joining method that is reliable and extremely advantageous in terms of construction. Has been.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. The present invention provides a concrete joining method for joining concrete on a vertical joining surface in reinforced concrete construction. In the concrete joining method according to the present invention, first, a partition plate corresponding to a required vertical joining surface of concrete is manufactured based on a design drawing of a reinforced concrete structure to be constructed. This partition plate is made of a metal plate or a high-strength resin plate, and has a shape and size corresponding to the vertical joint surface of concrete or a shape and size including the vertical joint surface of concrete. By setting the dimensions, even when placing highly fluid concrete, it effectively prevents the concrete mortar part from leaking through the partition plate, and functions as a concrete stopper. Can be suitably achieved. An example of a preferable material in the case of using a metal plate as a material of the partition plate is a steel plate, and an example of a preferable material in the case of using a high-strength resin plate is polycarbonate, but other appropriate materials are used. It is also possible.

  When the partition plate is manufactured, a reinforcing bar insertion hole is further formed at a position corresponding to the reinforcing bar to be arranged. In addition, the partition plate is formed with protrusions or concavo-convex portions that can transmit a shearing force between the both sides of the partition plate and the concrete placed in contact with the surfaces. FIG. 1 shows reinforcing bar insertion holes 12 and 14 as two specific examples of reinforcing bar insertion holes formed in the partition plate 10, and specific examples of protrusions or irregularities formed on both sides of the partition plate 10. The ridge pattern 16 is shown. In FIG. 1, the reinforcing bar insertion hole 12 is formed as a circular hole having a diameter slightly larger than the diameter of the reinforcing bar inserted through the reinforcing bar insertion hole 12. When the difference between the diameter of the reinforcing bar to be inserted and the diameter of the reinforcing bar insertion hole 12 is too small, the workability of the reinforcing bar assembly work is lowered. On the other hand, when the difference is too large, when high-fluidity concrete is placed. The concrete or the mortar portion of the concrete easily leaks from the gap between the reinforcing bar and the reinforcing bar insertion hole 12. Therefore, the diameter of the reinforcing bar insertion hole 12 is preferably set to a diameter as close as possible to the diameter of the reinforcing bar to be inserted within a range that does not hinder the reinforcing bar assembly work.

  Another specific example of the reinforcing bar insertion hole 14 is formed as a circular hole having a diameter equal to or smaller than the diameter of the reinforcing bar inserted through the reinforcing bar insertion hole 14 and having a radial cut around it. It is. The reinforcing bar insertion hole formed in the partition plate 10 can be in the form of the reinforcing bar insertion hole 14 because the metal plate or the high-strength resin plate used as the material of the partition plate 10 is relatively thin and flexible. This is the case. If the form of the reinforcing bar insertion hole 14 is adopted, the leakage of the concrete or the mortar part of the concrete from the reinforcing bar insertion hole part can be suitably suppressed without reducing the workability of the reinforcing bar assembly work.

  As a specific example of the protrusions or irregularities formed on both surfaces of the partition plate 10, FIG. 1 shows a protrusion pattern 16 formed on the surface of the partition plate 10. The ridge pattern 16 is similar to the ridge pattern formed on a normal striped steel plate. Therefore, it is also possible to use a commercially available double-sided striped steel plate as a material of the partition plate 10, and cuts such a steel plate into a required shape and size, and a reinforcing bar insertion hole at a position corresponding to the reinforcing bar to be arranged. By forming this, the partition plate 10 can be easily manufactured. The form of the protrusions or irregularities formed on each of both surfaces of the partition plate can be various forms other than the form of the protrusion pattern 16 shown in FIG. Another embodiment will be described.

  As described above, when the partition plate corresponding to the required vertical joint surface of the concrete is manufactured, the partition plate is positioned at the position where the vertical joint surface is formed, and the reinforcing plate insertion hole of the partition plate Reinforcing bars are inserted into the assembly of the reinforcing bars, and the formwork necessary for placing concrete is erected. Then, the precast concrete is placed so as to be in contact with one surface of the partition plate, the post-cast concrete is placed so as to be in contact with the other surface of the partition plate, and the mold is disassembled after the concrete is cured. Thus, the concrete joining method according to the present invention is completed. According to this concrete jointing method, the partition plate on which the vertical joint surface is formed is buried between the precast concrete and the postcast concrete without being removed. In addition, since the shearing force is transmitted between the partition plate and the precast concrete and between the partition plate and the postcast concrete through the protrusions or irregularities formed on the partition plate, Shear force is transmitted between the cast concrete.

    2 to 4 are elevational views showing three application examples in the case where the concrete splicing method according to the present invention is applied to a reinforced concrete girder on site. These drawings are cross-sectional views along a vertical plane perpendicular to the axis of the large beam, and show a state before placing the concrete of the large beam. Moreover, in each figure, the rebar 18 of the large beam that has been assembled, the formwork 20 that has been installed, and the partition plates 10A, 10B, and 10C are shown. These partition plates 10A, 10B, and 10C are manufactured in the shape and dimension corresponding to the vertical joint surface of concrete.

  In the application example shown in FIG. 2, the reinforcing bar insertion hole 12 and the protrusion pattern 16 described with reference to FIG. 1 are formed in the partition plate 10A. In the application example shown in FIG. 3, the reinforcing bar insertion hole 14 and the protrusion pattern 16 described with reference to FIG. 1 are formed in the partition plate 10B. In the application example shown in FIG. 4, the reinforcing bar insertion hole 12 described with reference to FIG. 1 is formed in the partition plate 10C. Further, a sheer cotter 22 is formed on the partition plate 10C shown in FIG. 4 instead of the protrusion pattern 16 shown in FIG. The shear cotter 22 is a convex portion having a quadrangular pyramid shape when the partition plate 10C is viewed from the front side in FIG. 4, and has a concave portion having a quadrangular pyramid shape when the partition plate 10C is viewed from the back side. The shear cotter 22 can transmit a shearing force between the concrete placed in contact with both surfaces of the partition plate 10C and the partition plate 10C, and thus one surface of the partition plate 10C. A shearing force can be transmitted between the concrete placed in contact with the concrete and the concrete placed in contact with the other surface. This function of the shear cotter 22 is the same as the function of the protrusion pattern 16 of FIG. However, when the shear cotter 22 is employed as shown in FIG. 4, the effect of preventing the partition plate 10C from being bent by the pressure of the placed concrete is also obtained. In the application example of FIG. 4, only one relatively large shear cotter is formed at the center of the partition plate 10C, but a plurality of smaller shear cotters may be formed side by side.

  FIG. 5 is an elevational sectional view showing an application example in which the concrete splicing method according to the present invention is applied to a reinforced concrete wall cast on the spot. This figure is a cross-sectional view along a vertical plane perpendicular to the extending surface of the wall, and shows a state before placing concrete on the wall. In FIG. 5, the partition plate 10 </ b> D is manufactured in a shape and size corresponding to a vertical joint surface of concrete so as to be accommodated in the mold 20. Moreover, the reinforcing plate insertion hole 14 and the protrusion pattern 16 which were demonstrated in relation to FIG. 1 are formed in this partition plate 10D, and the reinforcing bar 18 is inserted in the reinforcing bar insertion hole 14.

  FIG. 6 is an elevational cross-sectional view, in which both the precast concrete column (PCa column) 32 made of high-strength concrete and the precast concrete large beam (PCa large beam) 34 are in-situ. This is an application example when the invention is applied. This figure is a cross-sectional view along a vertical plane orthogonal to the axis of the PCa large beam 34. In FIG. 6, the PCa column 32 having a length substantially corresponding to the height of the first floor has a column main bar end (not shown) extending upward from the upper end surface 36 of the concrete portion. The end of the main beam of the PCa beam 34 (not shown) extends from both ends of the concrete portion. After placing the end of the concrete part of the PCa beam 34 on the edge of the upper end surface 36 of the concrete part of the PCa column 32 and arranging the bars, the joint between the column and the beam (column / beam joint) Concrete is placed in the upper part of the beam and the floor slab. The upper part of the girder and the floor slab are continuous in the horizontal direction. Here, the bottom of the column / beam joint corresponds to the horizontal section of the PCa column 32, and its height extends from the lower surface of the PCa large beam 34 to the upper surface of the completed large beam (this is also the upper surface of the floor slab) 38. It is a rectangular parallelepiped part equal to the dimension of the above, and it is desirable to place high-strength concrete in this part. On the other hand, normal strength concrete is sufficient as the concrete to be placed on the upper part of the girder and on the floor slab. In view of this, in the rectangular parallelepiped column / beam joint, the four side surfaces of the portion corresponding to the height of the PCa large beam 34 are surrounded by the end surface of the PCa large beam 34 and the general steel mold 40. And about the part exceeding the height of the PCa large beam 34, the four side surfaces are enclosed by the partition plate 10E which concerns on this invention. As described above, since the periphery of the column / beam joint is completely surrounded, high-strength concrete is placed there. The partition plate 10E is formed with a reinforcing bar insertion hole 44 through which the main beam main bar 42 arranged on the upper part of the large beam hitting the site is inserted, and a reinforcing bar insertion hole 48 through which the reinforcing bar 46 of the floor slab is inserted. The reinforcing bar insertion holes 44 and 48 are the same as the reinforcing bar insertion holes 12 and 14 of FIG. Also, in the figure, reference numeral 50 is a steel formwork that defines the bottom of the floor slab. When high-strength concrete has been placed in the column / beam joint, it is common for the top of the large beam and the floor slab Placing strong concrete.

  FIG. 7 shows a flat cross-sectional view of an application example in the case of applying the concrete joining method according to the present invention in order to succeed in-situ reinforced concrete columns and reinforced concrete beams. The illustrated partition plate 10F is made larger than the beam cross section, and has a shape and a dimension including a vertical joint surface of concrete. In this application example, after the column part mold 52 is built, the partition plate 10F is fixed to the mold 52 via the wood 54, and then the beam part mold 56 is built. . In the figure, 58 is a column main reinforcement, and the beam main reinforcement 60 is inserted through a reinforcing bar insertion hole formed in the partition plate 10F. This application is for cases where the concrete strength used for the columns and beams is different. If it is inconvenient that the side edge of the partition plate 10F protrudes from the concrete after the mold is disassembled, appropriate measures such as concealing or cutting and removing the portion are taken.

  FIG. 8 is a plan sectional view showing an application example of the present invention in the case where a site similar to FIG. 7 is constructed underground. In the case of FIG. 8 as well, the partition plate 10G is manufactured to be larger than the beam cross section, and has a shape and a dimension including a vertical joint surface of concrete. In this application example, a main pile (H-shaped steel) 66 that supports the soil 64 via the horizontal sheet piles 62 is used, and one side edge of the partition plate 10G is welded to the main pile 66, and the other The side edges are fixed to the column form 52 through the wood 54 as in FIG. In the figure, 56 is a formwork of a beam portion, 58 is a column main reinforcement, and 60 is a beam main reinforcement. In addition, a water stop plate 68 is attached to the partition plate 10G to prevent infiltration of groundwater. The water stop plate 68 is fixed to at least one surface of the partition plate with a plate piece extending perpendicularly to the extending direction of the partition plate, and with the plate piece, the placed concrete is in contact with the concrete. This is a water stop plate that suppresses the permeation of water through the surface. The water stop plate 68 further has a function of increasing the vertical rigidity of the partition plate and supporting the load of the reinforcing bar.

It is a perspective view of the partition plate used for the concrete splicing method according to the present invention, and is a view showing a concrete example of a reinforcing bar insertion hole formed in the partition plate and a protrusion or an uneven portion. It is a figure showing the 1st example of application of the present invention, and is an elevation sectional view of a reinforced concrete big beam in the state before placing concrete. It is a figure showing the 2nd example of application of the present invention, and is an elevation sectional view of a reinforced concrete big beam in the state before placing concrete. It is the figure which showed the 3rd example of application of this invention, and is a vertical sectional view of the reinforced concrete large beam in the state before placing concrete. It is the figure which showed the 4th example of application of this invention, and is a vertical sectional view of the reinforced concrete wall in the state before placing concrete. It is the figure which showed the 5th example of application of this invention, and is the elevation sectional view which showed the junction part of a precast concrete pillar and a precast concrete large beam It is the figure which showed the 6th example of application of this invention, and is a plane sectional view of the joint part of a reinforced concrete pillar and a reinforced concrete beam. It is the figure which showed the 7th example of application of this invention, and is a plane sectional view of the joint part of a reinforced concrete pillar and a reinforced concrete beam.

Explanation of symbols

  10, 10A, 10B, 10C, 10D, 10E, 10F, 10G ... partition plate, 12 ... rebar insertion hole, 14 ... rebar insertion hole, 16 ... protrusion pattern, 18 ... rebar, 20 ... mold Frame, 22 ... Shear cotter, 32 ... Precast concrete column, 34 ... Precast concrete beam, 42 ... Main beam main bar, 44 ... Reinforcing bar insertion hole, 46 ... Reinforcing bar, 48 ... Reinforcing bar insertion hole, 50 ... Formwork, 52... Formwork, 56... Formwork, 60.

Claims (6)

A concrete jointing method for joining concrete with a vertical joint surface in reinforced concrete construction,
It consists of a metal plate or a high-strength resin plate and has a shape and size corresponding to the vertical joint surface of concrete or a shape and size that includes the vertical joint surface of concrete. A partition plate is formed in which a hole is formed, and each of its both surfaces is formed with protrusions or irregularities that can transmit a shearing force with concrete placed in contact with the surface,
Assemble the reinforcing bars by inserting the reinforcing bars through the reinforcing bar insertion holes of the dividing plate so that the partition plate is positioned at the position where the vertical joining surface is formed,
Build the formwork,
Placing pre-cast concrete so as to contact one surface of the partition plate,
Placing post-cast concrete so as to contact the other surface of the partition plate,
Dismantling the formwork after curing the concrete,
Concrete jointing method characterized by that.   The concrete jointing method according to claim 1, wherein the protrusions or irregularities of the partition plate are formed as a ridge pattern formed on the surface of the partition plate.   2. The concrete splicing method according to claim 1, wherein the projecting portion or the uneven portion of the partition plate is a shear cotter formed on the partition plate.   The concrete joining method according to claim 1, wherein the reinforcing bar insertion hole is a circular hole having a diameter slightly larger than a diameter of a reinforcing bar inserted through the reinforcing bar insertion hole.   The metal plate or high-strength resin plate used as the material of the partition plate is a flexible metal plate or high-strength resin plate, and the reinforcing bar insertion hole has the same diameter as the diameter of the reinforcing bar inserted into the reinforcing bar insertion hole or The concrete jointing method according to claim 1, characterized in that it is a circular hole having a smaller diameter and having a radial cut around it.   A plate piece extending perpendicularly to the extending direction of the partition plate is fixed to at least one surface of the partition plate, and the plate piece is provided between the placed concrete and the surface of the partition plate in contact with the concrete. 2. The concrete joining method according to claim 1, wherein the water stopping plate suppresses the penetration of water through the gap.

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