JP4441438B2 - Reinforced concrete member joining structure and method for joining reinforced concrete members - Google Patents

Description

  The present invention relates to a joining structure of a reinforced concrete member for joining a substantially rod-shaped first reinforced concrete member and a second reinforced concrete, and a method for constructing the joining structure of the reinforced concrete member.

  Conventionally, the structure of the place where the pile head of the cast-in-place reinforced concrete pile (hereinafter referred to as “cast-in-place RC pile”) and the footing are joined is the main rebar of the pile (the rebar arranged in the vertical vertical direction of the pile), It is generally formed by directly joining the main reinforcing bars of the footing and binding them with steel wires, etc., placing reinforcing reinforcing bars (band reinforcing bars, hoop reinforcing bars, etc.) around it, and then placing concrete. (For example, see Patent Document 1).

  In addition, the amount of reinforcing bars (band reinforcing bar, hoop reinforcing bar, etc.) of the pile head (joint with the footing) is approximately the same as the amount of reinforcing bars (band reinforcing bar, hoop reinforcing bar, etc.) of the body part of the cast-in-place RC pile. It was common to set the same.

However, there is currently a strong demand for the development of a joint structure for reinforced concrete members in which the strength and deformation performance of the pile head joints are equal to or higher than those of the conventional method and the construction cost is low.
JP 2003-268787 A

  The present invention has been made to solve the above problems, and the problem to be solved by the present invention is that the strength and deformation performance of the pile head joint are equal to or higher than those of the conventional method described above, and the construction cost. Another object of the present invention is to provide a joint structure for reinforced concrete members and a construction method thereof.

In order to solve the above-mentioned problem, a joining structure of a reinforced concrete member according to claim 1 of the present invention,
A first reinforced concrete in which a plurality of first main reinforcing bars are arranged so as to form a cylindrical envelope surface along the first main reinforcing bar direction which is the main reinforcing bar direction of the first concrete inside the substantially rod-shaped first concrete. A structure for joining a member and a second reinforced concrete member in which a second main reinforcing bar is disposed inside the second concrete,
The outer diameter of the first joint part, which is a part of the first reinforced concrete member joined to the second reinforced concrete member, and the outer diameter of the first general part, which is a part of the first reinforced concrete member other than the first joint part, Equal,
Passing the plurality of first main reinforcing bars in the first general part through the concrete of the first joint, extending and fixing the tip position so as to enter the second reinforced concrete member,
The first general part reinforcing reinforcing bar is arranged so as to surround the first main reinforcing bar in the first general part so as to be substantially perpendicular to the first main reinforcing bar direction,
Surrounding the first main rebar at the first joint and the vertical adjoining portion thereof in the vertical direction, the rebar is approximately perpendicular to the first main rebar direction, and the amount of rebar is the amount of the first general reinforcing bar. dense reinforcement section reinforcing rebar is placed so as to be larger than,
A synthetic resin sheet is installed in a substantially cylindrical shape so as to surround the plurality of first main reinforcing bars in a first boundary portion that is a portion of the first joint portion in contact with the second reinforced concrete member. And
Moreover, the joining structure of the reinforced concrete member according to claim 2 of the present invention is as follows.
In the joining structure of the reinforced concrete member according to claim 1,
The sheet surrounds the plurality of first main reinforcing bars in a second boundary portion that is a portion of the second concrete member in contact with the first boundary portion.
It is characterized by.
Moreover, the joining structure of the reinforced concrete member according to claim 3 of the present invention is as follows.
In the joining structure of the reinforced concrete member according to claim 1,
The first reinforced concrete member is characterized by having a groove-shaped notch that surrounds the first concrete in an annular shape on the outer surface of the first concrete outside the sheet .

Moreover, the joining structure of the reinforced concrete member according to claim 4 of the present invention is
In the joining structure of the reinforced concrete member according to claim 1,
The length of the first joint portion in the first main reinforcing bar direction is set to be not more than twice the outer diameter of the concrete of the first joint portion.

Moreover, the joining structure of the reinforced concrete member according to claim 5 of the present invention is
In the joining structure of the reinforced concrete member according to claim 1,
The inner diameter of the tube of the envelope surface formed by the first main reinforcing bar of the first joint is set to be a value larger than 50 centimeters.

Moreover, the joining structure of the reinforced concrete member according to claim 6 of the present invention is
In the joining structure of the reinforced concrete member according to claim 1,
The ratio of the value of the installation interval in the first main reinforcing bar direction of the dense reinforcing bar section reinforcing bar to the value of the installation interval in the first main reinforcing bar direction of the first general portion reinforcing reinforcing bar is 0.1 or more and 0. Set to be 5 or less,
And the value of the space | gap between the said adjacent close reinforcing bar area reinforcement reinforcing bars is set so that it may become a value larger than 40 millimeters.

Moreover, the joining structure of the reinforced concrete member according to claim 7 of the present invention is
In the joining structure of the reinforced concrete member according to claim 1,
The first reinforced concrete member is a cast-in-place concrete pile, and the second reinforced concrete member is a footing or a joint between an underground beam and a column, or a slab.

Moreover, the joining structure of the reinforced concrete member according to claim 8 of the present invention is
In the joining structure of the reinforced concrete member according to claim 1,
The first reinforced concrete member is a column, and the second reinforced concrete member is a node portion of a beam.

Moreover, the joining structure of the reinforced concrete member according to claim 9 of the present invention is
In the joining structure of the reinforced concrete member according to claim 1,
The first reinforced concrete member is a beam, and the second reinforced concrete member is a nodal portion of a column and a beam.

Moreover, the joining structure of the reinforced concrete member according to claim 10 of the present invention is
In the joining structure of the reinforced concrete member according to claim 1,
A cross-sectional shape of the first reinforced concrete member is circular or rectangular.

Moreover, the joining structure of the reinforced concrete member according to claim 11 of the present invention is
In the joining structure of the reinforced concrete member according to claim 1,
The dense reinforcing bar section reinforcing bar is a reinforcing bar formed in a spiral shape.

Moreover, the joining structure of the reinforced concrete member according to claim 12 of the present invention is
In the joining structure of the reinforced concrete member according to claim 1,
The first general portion reinforcing reinforcing bar is a reinforcing bar formed in a spiral shape.

Moreover, the joining method of the reinforced concrete member which concerns on Claim 13 of this invention is the following.
A first reinforced concrete in which a plurality of first main reinforcing bars are arranged so as to form a cylindrical envelope surface along the first main reinforcing bar direction which is the main reinforcing bar direction of the first concrete inside the substantially rod-shaped first concrete. A method of joining a member and a second reinforced concrete member in which a second main reinforcing bar is disposed inside the second concrete,
The outer diameter of the first joint part, which is a part of the first reinforced concrete member joined to the second reinforced concrete member, and the outer diameter of the first general part, which is a part of the first reinforced concrete member other than the first joint part, Equal,
Passing the plurality of first main reinforcing bars in the first general part through the concrete of the first joint, extending and fixing the tip position so as to enter the second reinforced concrete member,
The first general part reinforcing reinforcing bar is arranged so as to surround the first main reinforcing bar in the first general part so as to be substantially perpendicular to the first main reinforcing bar direction,
Surrounding the first main rebar at the first joint and the vertical adjoining portion thereof in the vertical direction, the rebar is approximately perpendicular to the first main rebar direction, and the amount of rebar is the amount of the first general reinforcing bar. dense reinforcement section reinforcing rebar is placed so as to be larger than,
A synthetic resin sheet is installed in a substantially cylindrical shape so as to surround the periphery of the plurality of first main reinforcing bars in a first boundary portion that is a portion of the first joint portion in contact with the second reinforced concrete member,
Concrete of the first reinforced concrete member and the second reinforced concrete member is placed .

Moreover, the joining method of the reinforced concrete member which concerns on Claim 14 of this invention is the following.
In the joining method of the reinforced concrete member according to claim 13 ,
A substantially annular boundary concrete form made of polystyrene resin is disposed so as to surround the plurality of first main reinforcing bars in a first boundary portion that is a portion of the first joint portion in contact with the second reinforced concrete member, and Placing the concrete of the first reinforced concrete member and the second reinforced concrete member so that the outer diameter of the first boundary portion is smaller than the surroundings and a substantially annular groove is formed on the outer periphery of the first reinforced concrete member. Features.

Moreover, the joining method of the reinforced concrete member which concerns on Claim 15 of this invention is the following.
In the joining method of the reinforced concrete member according to claim 13 ,
The length of the synthetic resin sheet in the first main reinforcing bar direction is set to be not more than twice the outer diameter of the concrete of the first joint portion.

Moreover, the joining method of the reinforced concrete member concerning Claim 16 of this invention is the following.
In the joining method of the reinforced concrete member according to claim 13 ,
Before Symbol substantially tubular shape said sheet made of synthetic resin so as to surround the ambient of the first main rebar portion at which you Keru the plurality of second border of the second concrete member in contact with the first boundary It is characterized by installation.
Moreover, the joining method of the reinforced concrete member concerning Claim 17 of this invention is the following.
In the joining method of the reinforced concrete member according to claim 13,
Forming a groove-shaped notch that surrounds the first concrete in an annular shape on the outer surface of the first concrete outside the sheet;
It is characterized by.

According to the joining structure of the reinforced concrete member and the joining method of the reinforced concrete member according to the present invention, the cylindrical envelope along the first main reinforcing bar direction which is the main reinforcing bar direction of the first concrete inside the substantially rod-shaped first concrete. A structure in which a first reinforced concrete member in which a plurality of first main reinforcing bars are arranged so as to form a surface and a second reinforced concrete member in which a second main reinforcing bar is arranged in the second concrete are joined, The outer diameter of the first joint part, which is the part of the first reinforced concrete member joined to the reinforced concrete member, is made equal to the outer diameter of the first general part, which is the part of the first reinforced concrete member other than the first joint part. The plurality of first main reinforcing bars in the section are passed through the concrete in the first joint, and the tip positions thereof enter the second reinforced concrete member. The first general portion reinforcing reinforcing bar is disposed so as to be long and fixed and surround the first main reinforcing bar in the first general portion so as to be substantially perpendicular to the first main reinforcing bar direction. The dense reinforcing bar section reinforcing bar surrounds the first main reinforcing bar in the upper and lower adjacent portions so that it is substantially perpendicular to the direction of the first main reinforcing bar and the amount of reinforcing bar is larger than the amount of the first general part reinforcing bar. Since it comprised so that it might be arrange | positioned, it has the advantage that the intensity | strength and deformation | transformation performance of the reinforced concrete of the 1st junction part vicinity can be increased rather than the conventional structure.
Moreover, in the joining structure of a reinforced concrete member, the concrete outside the sheet near the first boundary portion exerts an action of preventing the adhesion of the first main reinforcing bar and the concrete. For this reason, at the time of an earthquake, a part or all of the concrete outside the sheet near the first boundary part is peeled off. As a result, the concrete stress generated in the concrete of the first reinforced concrete or the second reinforced concrete due to the earthquake is not completely transmitted to the first main reinforcing bar, and a part of the stress is reduced by the peeling of the concrete. Therefore, the rebar stress of the first main reinforcing bar does not become excessive even during an earthquake, and the breakage of the first main reinforcing bar is prevented. In this case, even if the concrete is peeled off, the sheet is waterproof, so the internal first main rebar and the dense rebar section rebar can be protected from external moisture. Corrosion can be prevented.

  The embodiment described below adopts a cast-in-place RC pile as the first reinforced concrete member and a footing as the second reinforced concrete member as an example, and is a part of the cast-in-place RC pile joined to the footing. The outer diameter is made equal to the outer diameter of the first general part which is a part of the first reinforced concrete member other than the first joint, and the plurality of first main reinforcing bars in the first general part are passed through the concrete of the first joint. The first general part is extended and fixed so as to enter the inside of the second reinforced concrete member, and surrounds the first main reinforcing bar in the first general part so as to be substantially perpendicular to the first main reinforcing bar direction. Reinforcing bars are arranged, and surround the first main reinforcing bar at the first joint and its vertically adjacent locations and are substantially perpendicular to the first main reinforcing bar direction, and the amount of reinforcing bar is the first. This is a configuration in which dense reinforcing bar section reinforcing bars are arranged so as to be larger than the amount of general reinforcing bars, and the strength and deformation performance of reinforced concrete near the first joint can be increased compared to the conventional configuration. It is the best mode as a configuration for realizing the invention.

  Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a vertical sectional view in the vertical direction showing the structure of a cast-in-place RC pile / footing joint structure according to a first embodiment of the present invention. FIG. 2 is a horizontal cross-sectional view showing the structure of the cast-in-place RC pile / footing joint structure according to the first embodiment of the present invention. 2, FIG. 2 (A) shows a cross-sectional view as seen from the direction AA in FIG. Moreover, in FIG. 2, FIG. 2 (B) has shown the expanded sectional view which expanded a part of FIG. 2 (A). FIG. 3 is an enlarged vertical sectional view in the vertical direction showing a configuration in the vicinity of the first boundary portion of a variation example of the cast-in-place RC pile / footing joint structure according to the first embodiment of the present invention. FIG. 4 is an enlarged vertical sectional view in the vertical direction showing a configuration in the vicinity of the first boundary portion of another variation of the cast-in-place RC pile / footing joint structure according to the first embodiment of the present invention. 4, FIG. 4B shows an enlarged cross-sectional view in which the vicinity of the first boundary portion in FIG. 4A is further enlarged.

  As shown in FIGS. 1 and 2, the cast-in-place RC pile / footing joint structure 101 of the first embodiment is a structure in which the vicinity of the head of the cast-in-place RC pile 1 and the footing 2 are joined. Here, the cast-in-place RC pile / footing joint structure 101 corresponds to the joint structure of reinforced concrete members in the claims. The cast-in-place RC pile 1 corresponds to the first reinforced concrete member in the claims. The footing 2 corresponds to the second reinforced concrete member in the claims.

  The footing 2 is a reinforced concrete beam or a reinforced concrete slab formed by arranging a second main reinforcing bar (not shown) inside the second concrete 5. In FIG.1 and FIG.2, in order to avoid the figure complexity, the 2nd main reinforcement is abbreviate | omitting illustration. For example, the second main reinforcing bars are arranged in the vicinity of the lower portion of the footing 2 so as to extend in the left-right direction in FIGS.

  The vicinity of the head of the cast-in-place RC pile 1 is constituted by a first joint portion 11 and a first general portion 12. In the vicinity of the head of the cast-in-place RC pile 1, a portion other than the first joint portion 11 is a first general portion 12. A portion of the first joint portion 11 in the vicinity of a portion in contact with the footing 2 is a first boundary portion 13.

  The first joint portion 11 of the cast-in-place RC pile 1 is a substantially round bar-like or substantially columnar member, the first concrete 3, the first main reinforcing bar 25, the dense reinforcing bar section reinforcing bar 28, and the sheet. 31 is comprised. The first main reinforcing bar 25 has a fixing end 25a, which is a tip (upper end in the vertical direction), fixed inside the second concrete 5 of the footing 2, and the fixing end 25a is bent in a substantially semicircular hook shape. The lower part is a straight vertical part 25b.

  The first main reinforcing bars 25 are provided in the first concrete 3 in the second concrete 5 of the footing 2, the first concrete 3 of the first joint 11, and the first concrete 4 of the first general part 12. A plurality are arranged so as to extend in parallel along the main reinforcing bar direction (hereinafter referred to as “first main reinforcing bar direction”; vertical vertical direction in FIG. 1) of the cast-in-place RC pile 1. The plurality of first main reinforcing bars 25 are cross sections that are substantially perpendicular to the first main reinforcing bar direction (horizontal cross section, not shown; see FIGS. 2A and 2B). When viewed from the inside, the plurality of first main reinforcing bars 25 are arranged so as to be lined up on a certain circumference, and the first concrete 3 and 4 and the second concrete 5 have a substantially cylindrical envelope. A surface is formed.

  Further, when the outer shape of the first joint portion 11 is viewed, the outer diameter thereof is equal to the outer diameter of the first general portion 12, and the cross-sectional area thereof is equal to the cross-sectional area of the first general portion 12.

  Next, the reinforcing steel bars will be described. In a location below the dense reinforcing bar section start end 24a of the first general part 12, a substantially annular first general part reinforcing bar 27 is disposed around the first main reinforcing bar 25 so as to surround them. The first general part reinforcing bar 27 is substantially perpendicular to the first main reinforcing bar direction. The 1st general part reinforcement 27 is equivalent to the 1st general part reinforcement reinforcing bar in a claim.

  Further, in a section between the dense reinforcing bar section start end 24a and the dense reinforcing bar section end 24b of the footing 2 (hereinafter referred to as “dense reinforcing bar section”), a plurality of fixed first main reinforcing bars forming a substantially cylindrical surface envelope surface. A substantially annular dense reinforcing bar section band reinforcing bar 28 is arranged so as to surround the periphery of 25. The dense reinforcing bar section rebar 28 is substantially perpendicular to the first main reinforcing bar direction. The reinforcing bar amount of the dense reinforcing bar section band reinforcing bar 28 is set to be larger than the reinforcing bar amount of the first general part band reinforcing bar 27. The close reinforcing bar section reinforcing bar 28 corresponds to the close reinforcing bar section reinforcing bar in the claims.

  The sheet 31 is made of a synthetic resin material such as soft polyvinyl chloride, polyethylene, polypropylene, polyester, polyamide resin, vinylon fiber (polyvinyl alcohol fiber or polyvinyl formal fiber), and has a thickness of 0.1 to 1. A thin film of about 0.0 millimeters, or a film or sheet-like member. An adhesive (not shown) is applied to the back surface of the sheet 31, and the vicinity of the substantially annular dense reinforcing bar section rebar 28 in the vicinity of the first boundary portion 13, that is, the first main reinforcing bar 25. It is bonded in a substantially cylindrical shape so as to surround (cover) the periphery. The synthetic resin sheet 31 is assembled before the concrete of the cast-in-place RC pile 1 is placed, for example, assembling the main reinforcing bar 25, the first general-part reinforcing bar 27, and the dense reinforcing-bar section reinforcing bar 28 of the cast-in-place RC pile 1. At the time of finishing, the concrete of the cast-in-place RC pile 1 is cast, and the cast-in-place RC pile 1 is constructed. Note that the sheet 31 surrounds (covers) the periphery of the dense rebar section band rebar 28, that is, the first main rebar 25, with an annealed iron wire, metal fittings, fasteners, or the like without using an adhesive. Thus, it may be installed in a substantially cylindrical shape.

  Next, the operation of the cast-in-place RC pile / footing joint structure 101 configured as described above will be described. The cast-in-place RC pile / footing joint structure 101 is a structure for joining the cast-in-place RC pile 1 having a substantially round bar shape extending in the first main reinforcing bar direction (vertical vertical direction in FIG. 1) and the footing 2. The RC pile 1 includes a first joint portion 11 and a first general portion 12. In the RC pile / footing joint structure 101, the outer diameter of the first joint portion 11 which is the portion of the cast-in-place RC pile 1 joined to the footing 2 is set to the portion of the cast-in-place RC pile 1 other than the first joint portion (first The dense reinforcing bar section rebar 28 is arranged so as to be equal to the outer diameter of the general part 12) and surround the plurality of first main reinforcing bars 25 in the first joint 11 so as to be substantially perpendicular to the first main reinforcing bar direction. To do. The amount of reinforcing bars of the dense reinforcing bar section band reinforcing bar 28 is set to be larger than the reinforcing bar amount of the first general part band reinforcing bar 27 of the first general part 12. For this reason, the strength and deformation performance of the reinforced concrete in the densely reinforced section, which is the first joint portion 11 and the portions adjacent to the top and bottom thereof (the upper portion of the first general portion 12 and the lower portion of the footing 2), are compared to the case of the conventional configuration. Can also be improved.

  Further, in the RC pile / footing joint structure 101, the concrete 14 outside the sheet 31 near the first boundary portion 13 exerts an action of preventing the adhesion of the first main reinforcing bar 25 and the concrete 14 to the sheet 31. For this reason, at the time of an earthquake, a part or all of the concrete 14 outside from the sheet 31 near the first boundary portion 13 is peeled off. Accordingly, the concrete stress generated in the concrete of the cast-in-place RC pile 1 or the footing 2 due to the earthquake is not transmitted to the first main reinforcing bar 25, and a part of the stress is reduced by the peeling of the concrete 14. Therefore, the reinforcing bar stress of the first main reinforcing bar 25 does not become excessive even during an earthquake, and the breaking of the first main reinforcing bar 25 is prevented. In this case, even if the concrete 14 is peeled off, the sheet 31 is waterproof, so that the internal first main rebar 25 and the dense reinforcing bar section rebar 28 can be protected from external moisture. And corrosion of the reinforcing bars can be prevented.

  Further, the length L1 of the first joint portion 11 in the first main reinforcing bar direction in the above is determined from the results of experiments and the like as the concrete outer diameter of the first joint portion 11 (or the outer diameter of the concrete of the first general portion 12). ) It is preferably set within a range of values that are not more than twice the value of D1.

  In addition, the inner diameter of the cylinder of the envelope surface formed by the first main reinforcing bar 25 of the first joint portion 11 (or the inner diameter of the cylinder of the envelope surface formed by the first main reinforcing bar 25 of the first general portion 12) D2 It is preferable that the value is set to a value larger than 50 centimeters so that the installation tremely tube can be smoothly inserted.

  Further, the ratio of the value of the installation interval L3 in the first main reinforcing bar direction of the dense reinforcing bar section band reinforcing bar 28 to the value of the installation interval L2 in the first main reinforcing bar direction of the first general part reinforcing bar 27 in the above is the result of experiments and the like. Therefore, it is preferably set within a range of values of 0.1 or more and 0.5 or less. In this case, the value of the gap L3 between the adjacent dense rebar section band rebars 28 is preferably set to a value larger than 40 millimeters so that the coarse aggregate of concrete spreads.

  Moreover, as for the installation length (installation length to the 1st main reinforcing bar direction) L6 of the perpendicular | vertical direction of the sheet | seat 31 in the above, the lower limit is preferable about 5-20 mm from the result of experiment etc. The upper limit of the installation length L6 in the vertical direction of the seat 31 is 2 of the outer diameter of the concrete of the first joint portion 11 (or the outer diameter of the concrete of the first general portion 12) D1 from the results of experiments and the like. It is preferably set within a range of values that are less than or equal to a double value.

  Further, as described above, the concrete 14 near the first boundary portion 13 and outside the sheet 31 is expected to be more actively peeled off during an earthquake. Therefore, the “cover thickness” of the concrete 14, that is, the distance between the outer surface of the sheet 31 and the outer surface of the concrete 14 may be a small value.

  Further, like the RC pile / footing joint structure 101A of the modified example of the first embodiment shown in FIG. 3, the sheet 31A is wound and bonded many times, and the substantially annular dense portion in the vicinity of the first boundary portion 13 is bonded. The outer surface position of the sheet 31A is such that the sheet 31A is adhered in a substantially cylindrical shape so as to surround (cover) the periphery of the reinforcing bar section reinforcing bar 28, that is, the periphery of the first main reinforcing bar 25. However, you may make it become equal to the position of the outer surface 11a of the 1st junction part 11. FIG. The material of the sheet 31A is the same as that of the sheet 31. In this case, there is no “cover concrete” outside the sheet 31A. If it does in this way, the concrete stress which generate | occur | produces in the concrete of the cast-in-place RC pile 1 and the footing 2 by an earthquake will not be transmitted to the 1st main reinforcement 25, but the one part will be attenuated. Therefore, the reinforcing bar stress of the first main reinforcing bar 25 does not become excessive even during an earthquake, and the breaking of the first main reinforcing bar 25 is prevented. In this case, since the sheet 31A is waterproof, the internal first main reinforcing bar 25 and the dense reinforcing bar section reinforcing bar 28 can be protected from external moisture, and corrosion of the reinforcing bar is prevented. be able to. Note that the sheet 31A surrounds (covers) the periphery of the dense rebar section band rebar 28, that is, the first main rebar 25 with an annealed iron wire, metal fittings, fasteners, or the like without using an adhesive. Thus, it may be installed in a substantially cylindrical shape.

  Further, like the RC pile / footing joint structure 101B of another modified example of the first embodiment shown in FIG. 4, the sheet 31 </ b> B is made of a substantially annular dense reinforcing bar section rebar 28 in the vicinity of the first boundary portion 13. The outer periphery of the first main rebar 25 is surrounded (covered) so as to be bonded in a substantially cylindrical shape, and the concrete 14B is positively peeled off during the earthquake on the outer surface of the concrete 14B outside the sheet 31B. Alternatively, groove-shaped notches 15a and 15b surrounding the concrete 14B in an annular shape may be formed. The material of the sheet 31B is the same as that of the sheet 31. In this way, the concrete stress generated in the concrete of the cast-in-place RC pile 1 or the footing 2 due to the earthquake is not all transmitted to the first main rebar 25, and a part of it is reduced by peeling off the concrete 14B. Is done. Therefore, the reinforcing bar stress of the first main reinforcing bar 25 does not become excessive even during an earthquake, and the breaking of the first main reinforcing bar 25 is prevented. In this case, since the sheet 31B is waterproof, the internal first main rebar 25 and the dense rebar section band rebar 28 can be protected from external moisture, and corrosion of the rebar is prevented. be able to. A plurality of annular notches may be provided in addition to 15a and 15b. Moreover, if the groove cross sections of the annular cutout portions 15a and 15b are formed in a “V” shape or the like, the concrete 14B can be more actively guided to peel off during an earthquake. Note that the sheet 31B surrounds (covers) the periphery of the dense rebar section band rebar 28, that is, the first main rebar 25 with an annealed iron wire, a metal fitting, a stopper, or the like without using an adhesive. Thus, it may be installed in a substantially cylindrical shape.

  The present invention can be realized by a configuration different from that of the first embodiment. Hereinafter, a second embodiment of the present invention will be described with reference to FIG. 5, FIG. 5 (A) is an enlarged vertical sectional view in the vertical direction showing the structure of a cast-in-place RC pile / footing joint structure according to the second embodiment of the present invention. Further, in FIG. 5, FIG. 5 (B) is a side view showing a state after bonding of the sheet 31C in the cast-in-place RC pile / footing joint structure which is the second embodiment of the present invention.

  As shown in FIG. 5A, the cast-in-place RC pile / footing joint structure 102 of the second embodiment is a structure that joins the vicinity of the head of the cast-in-place RC pile 1C and the footing 2C. Here, the cast-in-place RC pile / footing joint structure 102 corresponds to the joint structure of reinforced concrete members in the claims. The cast-in-place RC pile 1C corresponds to the first reinforced concrete member in the claims. The footing 2C corresponds to the second reinforced concrete member in the claims.

  The footing 2C has the same configuration as the above-described footing 2 except for a portion of a sheet 31C described later. Further, the vicinity of the head of the cast-in-place RC pile 1C has the same configuration as that of the cast-in-place RC pile 1 described above except for a portion of a sheet 31C described later.

  In the cast-in-place RC pile / footing joint structure 102 of the second embodiment, the portion of the first joint portion 11C in the vicinity of the portion in contact with the footing 2C (the length L7 portion in FIG. 5 (A). (Referred to as “boundary portion”) 13C and a portion of the footing 2C in the vicinity of the portion in contact with the first boundary portion 13C (the portion of length L8 in FIG. 5A. Hereinafter, referred to as “second boundary portion”) 16. The synthetic resin sheet 31C is bonded in a substantially cylindrical shape so as to surround the individual reinforcing bars of the plurality of first main reinforcing bars 25 in the range. The material of the sheet 31C is the same as that of the sheet 31. Further, the concrete placement of the cast-in-place RC pile 1C and the footing 2C is performed after the installation of the sheet 31C.

  If it does in this way, in the 1st boundary part 13C and the 2nd boundary part 16, sheet 31C will demonstrate the operation which prevents adhesion of the 1st main reinforcing bar 25, concrete 14C, and concrete 3. For this reason, the concrete stress which generate | occur | produces in the concrete of cast-in-place RC pile 1C or footing 2C by an earthquake is not transmitted to the 1st main reinforcement 25 in the 1st boundary part 13C and the 2nd boundary part 16. FIG. Therefore, the reinforcing bar stress of the first main reinforcing bar 25 does not become excessive even during an earthquake, and the breaking of the first main reinforcing bar 25 is prevented. In this case, since the sheet 31C is waterproof, the first main rebar 25 covered with the sheet 31C can be protected from external moisture, and corrosion of the rebar can be prevented. it can. Note that the sheet 31C surrounds (covers) the periphery of the dense reinforcing bar section band reinforcing bar 28, that is, the first main reinforcing bar 25 with an annealed iron wire, a metal fitting, a stopper, or the like without using an adhesive. Thus, it may be installed in a substantially cylindrical shape.

  In the cast-in-place RC pile / footing joint structure 102 of the second embodiment, a groove-shaped notch portion surrounding the concrete 14C in an annular shape as shown in FIG. 4 may be formed. If it does in this way, it will become possible to guide exfoliation of concrete 14C positively at the time of an earthquake.

  Moreover, it is preferable that the dimension of the sheet | seat adhesion length (length to a 1st main reinforcement direction) L7 and L8 in the above shall be the following values from the result of experiment etc. About sheet adhesion length (length to the 1st main reinforcing bar direction) L7 in the 1st boundary part, a lower limit is about 30 millimeters, an upper limit is a value 40 times the diameter of a main reinforcing bar, or the 1st joined part The value of the outer diameter of the concrete 11 (or the outer diameter of the concrete of the first general portion 12) D1 is preferably a value within this range. Regarding the sheet bonding length (length in the first main reinforcing bar direction) L8 at the second boundary portion, the lower limit value is about 30 mm, the upper limit value is a value 40 times the diameter of the main reinforcing bar, or the first joint portion. The value of the outer diameter of the concrete 11 (or the outer diameter of the concrete of the first general portion 12) D1 is preferably a value within this range. Moreover, if the value of L8 is set to be larger than the value of L7, it is possible to effectively prevent the lower part of the footing 2C from being destroyed during an earthquake.

  Further, as shown in FIG. 5B, the sheet 31 </ b> C is formed of a synthetic resin sheet made of the same material as the sheet 31 in an elongated tape shape (band shape), and spirally formed on the surface of the first main reinforcing bar 25. If the sheet 31C is bonded to the sheet 31C, it is possible to prevent concrete cement milk or mortar from entering between the sheet 31C and the first main reinforcing bar 25 from the end of the sheet 31C. And “adhesion prevention performance” can be further enhanced.

  The joint structure of reinforced concrete members according to the present invention can be used in combination with the following construction methods. FIG. 6 is a diagram for explaining a concrete placing method that can be used in each embodiment of the present invention.

  FIG. 6 shows a method for placing concrete in the first joint (for example, 11) and the footing (for example, 2) in the vicinity of the first boundary portion (for example, 13) in the first and second embodiments described above. Show. The arrangement and the like of the reinforcing bars are the same as those in the first and second embodiments described above. In FIG. 6, the reinforcing bars to be embedded in the concrete are not shown in order to avoid complexity. Yes. Moreover, the sheet | seat (for example, 31) made from a synthetic resin has already shown the state after adhere | attaching on a predetermined reinforcing bar.

  First, as shown in FIG. 6A, a boundary concrete form 52 made of a styrene resin is disposed around the first main reinforcing bar at a location that becomes the first joint near the first boundary. The boundary concrete form 52 is formed in a thick cylindrical shape. The inner diameter of the first joint portion of the boundary concrete mold 52 is set to be smaller than the outer diameter (for example, D1) of the surrounding (for example, the first general portion 12). Moreover, in FIG. 6A, the member shown with the code | symbol 51 has shown the whole mold form which consists of steel materials. The overall mold 51 includes a footing side mold 51 a and a footing bottom mold 51 b for forming the footing 2, and a pile attaching part 51 c. The pile attachment portion 51c supports the boundary concrete formwork 52 and attaches the footing side formwork 51a and the footing bottom formwork 51b to the upper end of the cast-in-place RC pile 1 with a coupling member (for example, a bolt) 53. And support.

  With the above configuration, as shown in FIG. 6 (B), the ready-mixed concrete C is placed in the space formed by the footing side mold 51a, the footing bottom mold 51b, and the boundary concrete mold 52. Once installed, the outer diameter of the part formed after removing the formwork is smaller than the surroundings (for example, the first joint part 11 other than the vicinity of the first boundary part), and the concrete cover thickness of that part is It becomes smaller than the concrete cover thickness of other parts. Therefore, for example, the cover thickness of the concrete 14 in the cast-in-place RC pile / footing joint structure 101 of the first embodiment shown in FIG. 1 is set smaller than the cover thickness of the concrete 4 of the other first joint portion 11. Is possible. Further, by making the cross-sectional shape of the boundary concrete form 52 described above into a “V” shape, the annular notch 15a shown in FIGS. 4A and 4B and the like may be formed on the concrete surface. Is possible.

  In addition, this invention is not limited to an above-described Example. The above-described embodiment is an exemplification, and any device having substantially the same configuration as the technical idea described in the claims of the present invention and having the same function and effect can be used. It is included in the technical scope of the present invention.

  For example, as a reinforcing reinforcing bar, a “helical reinforcing bar (spiral reinforcing bar)” may be used instead of the band reinforcing bar described in the above embodiments.

  Moreover, the cross-sectional shape of the cast-in-place concrete pile which is the 1st reinforced concrete member of this invention is not limited to a circular cross section, A rectangular cross section may be sufficient. In the present invention, the first reinforced concrete member may be a cast-in-place concrete pile, and the second reinforced concrete member may be a nodal portion of the underground beam and the column. Alternatively, the first reinforced concrete member may be a cast-in-place concrete pile and the second reinforced concrete member may be a slab. In this case, the cross-sectional shape of the cast-in-place concrete pile that is the first reinforced concrete member may be a circular cross section or a rectangular cross section.

  In the present invention, the first reinforced concrete member may be a column, and the second reinforced concrete member may be a nodal portion of the beam. In this case, the cross-sectional shape of the column that is the first reinforced concrete member may be a circular cross section or a rectangular cross section.

  In the present invention, the first reinforced concrete member may be a beam, and the second reinforced concrete member may be a nodal portion of a column and a beam. In this case, the cross-sectional shape of the beam that is the first reinforced concrete member may be a circular cross section or a rectangular cross section.

  Moreover, the structure which removed the sheet | seat 31 from the cast-in-place RC pile and footing joining structure 101 of the above-mentioned 1st Example may be sufficient. In this case, a groove-shaped cutout portion (for example, a groove width of about 10 to 50 mm) is provided in the portion of the first joint portion 11 that is in contact with the footing 2 so that the first main reinforcing bar 25 during an earthquake. You may make it prevent adhesion with concrete.

  INDUSTRIAL APPLICABILITY The present invention can be implemented in the civil engineering / architectural industry that performs the construction of a joint structure of reinforced concrete members and can be used in these industries.

BRIEF DESCRIPTION OF THE DRAWINGS It is a longitudinal cross-sectional view of the perpendicular direction which shows the structure of the cast-in-place RC pile and footing junction structure which is 1st Example of this invention. It is a horizontal cross-sectional view which shows the structure of the cast-in-place RC pile and footing junction structure which is 1st Example of this invention. It is the longitudinal cross-sectional view which expanded the vertical direction which shows the structure of the 1st boundary part vicinity of the example of a change of the cast-in-place RC pile and footing junction structure which is 1st Example of this invention. It is the longitudinal cross-sectional view which expanded the vertical direction which shows the structure of the 1st boundary part vicinity of the other modification of the cast-in-place RC pile and footing junction structure which is 1st Example of this invention. It is a figure which shows the structure of the cast-in-place RC pile and footing junction structure which is 2nd Example of this invention. It is a figure explaining the concrete placement method which can be used together in each Example of this invention.

Explanation of symbols

1-1C Cast-in-place RC pile (1st reinforced concrete member)
2-2C footing (2nd reinforced concrete member)
DESCRIPTION OF SYMBOLS 3 Joint part 1 concrete 4 General part 1 concrete 5 2nd concrete 11-11C 1st joint part 11a Outer surface of 1st joint part 12 1st general part 13-13C 1st boundary part 14, 14C Outside from a sheet | seat Concrete 15a, 15b Annular cutout 16 Second boundary 24a Closed bar section start 24b Closed bar section end 25 First main reinforcing bar 25a Anchoring end 25b Vertical section 27 First general section reinforcing bar (first general reinforcing bar)
28 Closed Rebar Section Reinforcing Bar (Closed Rebar Reinforcing Bar)
29 2nd concrete strip reinforcement 31-31C sheet 51 Overall formwork 51a Footing side formwork 51b Footing bottom formwork 51c Pile attachment part 52 Boundary part concrete formwork 53 Binding member 101-102 Cast-in-place RC pile and footing joint Structure (joint structure of reinforced concrete members)
D1 External diameter of the concrete of the first general part and the first joint D2 Diameter of the inner surface of the cylinder of the envelope surface formed by the first main rebar of the first general part and the first joint L1 Vertical length of the first joint L2 Vertical arrangement interval of the rebar 27 L3 Vertical arrangement interval of the rebar 28 L4 Vertical arrangement interval of the rebar 29 L5 Vertical length of the dense rebar section in the footing L6 to L8 Seat vertical Directional installation length

Claims (17)

A first reinforced concrete in which a plurality of first main reinforcing bars are arranged so as to form a cylindrical envelope surface along the first main reinforcing bar direction which is the main reinforcing bar direction of the first concrete inside the substantially rod-shaped first concrete. A structure for joining a member and a second reinforced concrete member in which a second main reinforcing bar is disposed inside the second concrete,
The outer diameter of the first joint part, which is a part of the first reinforced concrete member joined to the second reinforced concrete member, and the outer diameter of the first general part, which is a part of the first reinforced concrete member other than the first joint part, Equal,
Passing the plurality of first main reinforcing bars in the first general part through the concrete of the first joint, extending and fixing the tip position so as to enter the second reinforced concrete member,
The first general part reinforcing reinforcing bar is arranged so as to surround the first main reinforcing bar in the first general part so as to be substantially perpendicular to the first main reinforcing bar direction,
Surrounding the first main rebar at the first joint and the vertical adjoining portion thereof in the vertical direction, the rebar is approximately perpendicular to the first main rebar direction, and the amount of rebar is the amount of the first general reinforcing bar. dense reinforcement section reinforcing rebar is placed so as to be larger than,
A synthetic resin sheet is installed in a substantially cylindrical shape so as to surround the plurality of first main reinforcing bars in a first boundary portion that is a portion of the first joint portion in contact with the second reinforced concrete member. The joint structure of reinforced concrete members. In the joining structure of the reinforced concrete member according to claim 1,
The joint structure of reinforced concrete members, wherein the sheet surrounds the plurality of first main reinforcing bars in a second boundary portion which is a portion of the second concrete member in contact with the first boundary portion . In the joining structure of the reinforced concrete member according to claim 1,
The joining structure of a reinforced concrete member, wherein the first reinforced concrete member has a groove-shaped notch surrounding the first concrete in an annular shape on the outer surface of the first concrete outside the sheet . In the joining structure of the reinforced concrete member according to claim 1,
The length of the first joint portion in the direction of the first main reinforcing bar is set to be not more than twice the outer diameter of the concrete of the first joint portion. Construction. In the joining structure of the reinforced concrete member according to claim 1,
The joint structure of a reinforced concrete member, wherein an inner diameter of a tube of an envelope surface formed by the first main reinforcing bar of the first joint portion is set to a value larger than 50 centimeters . In the joining structure of the reinforced concrete member according to claim 1,
The ratio of the value of the installation interval in the first main reinforcing bar direction of the dense reinforcing bar section reinforcing bar to the value of the installation interval in the first main reinforcing bar direction of the first general portion reinforcing reinforcing bar is 0.1 or more and 0. Set to be 5 or less,
And the connection structure of the reinforced concrete member characterized by the value of the space | gap between the said adjoining dense reinforcing bar area reinforcement reinforcing bars becoming a value larger than 40 millimeters . In the joining structure of the reinforced concrete member according to claim 1,
The joint structure of reinforced concrete members, wherein the first reinforced concrete member is a cast-in-place concrete pile, and the second reinforced concrete member is a footing, an underground beam and a node of a column, or a slab . In the joining structure of the reinforced concrete member according to claim 1,
The first reinforced concrete member is a column, and the second reinforced concrete member is a nodal portion of a beam . In the joining structure of the reinforced concrete member according to claim 1,
The first reinforced concrete member is a beam, and the second reinforced concrete member is a nodal portion of a column and a beam . In the joining structure of the reinforced concrete member according to claim 1,
The joint structure of reinforced concrete members, wherein the cross-sectional shape of the first reinforced concrete member is circular or rectangular . In the joining structure of the reinforced concrete member according to claim 1,
The dense reinforcing bar section reinforcing bar is a reinforcing bar formed in a spiral shape.
A joint structure of reinforced concrete members characterized by   In the joining structure of the reinforced concrete member according to claim 1,
The first general part reinforcing bar is a reinforcing bar formed in a spiral shape.
A joint structure of reinforced concrete members characterized by A first reinforced concrete in which a plurality of first main reinforcing bars are arranged so as to form a cylindrical envelope surface along the first main reinforcing bar direction which is the main reinforcing bar direction of the first concrete inside the substantially rod-shaped first concrete. A method of joining a member and a second reinforced concrete member in which a second main reinforcing bar is disposed inside the second concrete,
The outer diameter of the first joint part, which is a part of the first reinforced concrete member joined to the second reinforced concrete member, and the outer diameter of the first general part, which is a part of the first reinforced concrete member other than the first joint part, Equal,
Passing the plurality of first main reinforcing bars in the first general part through the concrete of the first joint, extending and fixing the tip position so as to enter the second reinforced concrete member,
The first general part reinforcing reinforcing bar is arranged so as to surround the first main reinforcing bar in the first general part so as to be substantially perpendicular to the first main reinforcing bar direction,
Surrounding the first main rebar at the first joint and the vertical adjoining portion thereof in the vertical direction, the rebar is approximately perpendicular to the first main rebar direction, and the amount of rebar is the amount of the first general reinforcing bar. Dense reinforcing bar section reinforcing bars are arranged so as to be larger than
A synthetic resin sheet is installed in a substantially cylindrical shape so as to surround the plurality of first main reinforcing bars in a first boundary portion that is a portion of the first joint portion in contact with the second reinforced concrete member, A method for joining reinforced concrete members, comprising placing concrete of one reinforced concrete member and the second reinforced concrete member . In the joining method of the reinforced concrete member according to claim 13 ,
A substantially annular boundary concrete form made of polystyrene resin is disposed so as to surround the plurality of first main reinforcing bars in a first boundary portion that is a portion of the first joint portion in contact with the second reinforced concrete member, and Placing the concrete of the first reinforced concrete member and the second reinforced concrete member so that the outer diameter of the first boundary portion is smaller than the surroundings and a substantially annular groove is formed on the outer periphery of the first reinforced concrete member. A method for joining reinforced concrete members. In the joining method of the reinforced concrete member according to claim 13 ,
The length of the synthetic resin sheet in the first main reinforcing bar direction is set to be not more than twice the outer diameter of the concrete of the first joint portion . Joining method. In the joining method of the reinforced concrete member according to claim 13,
The synthetic resin sheet is installed in a substantially cylindrical shape so as to surround the plurality of first main reinforcing bars in the second boundary portion which is a portion of the second concrete member in contact with the first boundary portion.
The joining method of the reinforced concrete member characterized by this. In the joining method of the reinforced concrete member according to claim 13,
Forming a groove-shaped notch that surrounds the first concrete in an annular shape on the outer surface of the first concrete outside the sheet;
The joining method of the reinforced concrete member characterized by this.

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