JP3160121U - Rebar and rebar joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reinforcing bar capable of suppressing interference with a reinforcing bar which is a reinforcing bar different from a main reinforcing bar. A rebar 1 is used as a main reinforcing bar of reinforced concrete, and has a screw portion 3 having a diameter larger than that of a rebar main body 2 and having a male screw 4 formed on an outer periphery thereof. 6-9, and the ratio (d3 / d1) of the root diameter of the male screw 4 to the diameter of the rebar main body 1 is 1.05-1.50. It is preferable to form a corner portion 5 at the boundary between the screw portion 3 and the reinforcing bar body 2 in R. Moreover, it is preferable to form R by die forging performed in order to form the screw part 3 by expanding the end part of the reinforcing bar body 2 from the reinforcing bar body 2, and R is 1 to 3 of the pitch of the male screw 4. It is preferable to form with a diameter of twice the size. [Selection] Figure 1

Description

  The present invention relates to a reinforcing bar and a reinforcing bar joint used as main bars of reinforced concrete.

In reinforced concrete, a reinforced joint is used in order to make a reinforcing bar which is a main bar of a limited standard length into a continuous reinforcing bar in the field. As reinforced joints, lap joints and gas pressure welding joints that overlap the reinforcing bars for a predetermined length are common, but lap joints have complicated bar arrangement structure due to overlap, and gas pressure welding joints require the skill of pressure welding work. There is a drawback that the quality of the joint is affected.
Therefore, as a special joint, a joint has been developed in which grout is injected into the sleeve together with the reinforcing bar. This special joint for injecting grout is preferable in view of simplification of the bar arrangement structure, and has been put to practical use. However, for curing the grout, for example, a curing period of about one day is required and the construction period is long. is there.

  A threaded joint has been proposed as a joint that does not require a curing period (see, for example, Patent Document 1). This threaded joint is used to connect two reinforcing bars using a connector in a state in which the end portions are butted against each other. The end portions of the two reinforcing bars are respectively formed with screw portions whose diameter is larger than that of the reinforcing bar main body. Male screws having different spiral directions are formed on the outer circumferences of these screw portions. The joining tool is formed in a cylindrical shape. From the center of the inner peripheral surface of the connector to the one end, a first female screw is formed in which the male thread of the thread portion of one of the reinforcing bars is screwed, and the remaining inner peripheral surface is formed with the other reinforcing bar. A second female screw is formed in which the male screw of the screw part is screwed. That is, the spiral direction of the thread groove is different between the first female screw and the second female screw. By using this connector as a turnbuckle, both the reinforcing bars can be connected via the screw portion.

JP-A-11-336256

  However, in the conventional threaded joint, in order to form a screw part whose diameter is larger than that of the main part of the reinforcing bar at the end part of the reinforcing bar, if the axial length or diameter of the screw part is large, the screw part is particularly screwed. There is also a possibility that the connecting tool interferes with a reinforcing bar different from the main reinforcing bars arranged around the reinforcing bar. For example, reinforcing bars that are different from the main bars such as stirrup and hoop bars are arranged around the reinforcing bars that are the main bars of beams and columns connected by conventional screw joints. If the range of the threaded portion is wide and the height is high, the joint is further screwed onto the outer periphery of the threaded portion, so that the threaded portion, particularly the joint, may interfere with the reinforcing bar.

  The problem to be solved by the present invention is to suppress interference with a reinforcing bar which is a reinforcing bar different from the main bar.

  In order to solve the above-mentioned problem, a reinforcing bar according to the present invention is a reinforcing bar that is used as a main reinforcing bar of reinforced concrete, and has a threaded portion whose diameter is larger than that of a reinforcing bar main body and a male screw is formed on the outer periphery. The number of screw threads is 6 to 9, and the ratio of the root diameter of the male screw to the diameter of the reinforcing bar body is 1.05 to 1.50.

  Thus, when the number of threads of the male screw is 6 to 9, the axial length of the screw portion can be shortened. Moreover, the length of the radial direction of a thread part can be shortened as ratio of the valley diameter of the external thread with respect to the diameter of a reinforcing bar main body is 1.05-1.50. Therefore, since the range of the screw part protruding from the reinforcing bar main body is narrow and the height is low, when the reinforcing bar is connected using this screw part, the interference with the reinforcing bars arranged around the reinforcing bar is suppressed. be able to.

  In this case, the corner portion of the boundary between the screw portion and the reinforcing bar main body can be formed in R. Further, R can be formed by die forging performed to expand the diameter of the end of the reinforcing bar body from the reinforcing bar body to form a threaded portion. Moreover, R can be formed with a diameter of 1 to 3 times the pitch of the male screw.

  In order to solve the above-mentioned problem, a rebar joint according to the present invention is a rebar joint for connecting two rebars using a coupler in a state in which the end portions are abutted with each other. The coupler is characterized in that the spiral direction of the coupler is the same direction, the coupler has an inner peripheral surface formed in a circular cylindrical shape, and a female screw that engages with the male screw is formed on the inner peripheral surface of the coupler. .

  Thereby, since the range which protrudes from a rebar main body is narrow, and a coupler is screwed together in the thread part of two rebars which are low, two rebars are connected, and it suppresses interference with a reinforcing bar. be able to.

  In this case, the length of the coupler in the axial direction may be greater than or equal to the total length obtained by adding the axial lengths of the threaded portions of the two reinforcing bars and not longer than 15 mm longer than the total length. it can. Further, when two reinforcing bars are connected by a coupler, the amount of slip between these two reinforcing bars can be reduced to 0.3 or less.

  According to this invention, since the range of the screw part which protrudes from a reinforcing bar main body is narrow and height is low, interference with the reinforcing bar which is a reinforcing bar different from a main reinforcing bar can be suppressed.

It is a side view showing a reinforcing bar of an example embodiment concerning the present invention. It is a side view which shows the reinforcing bar of another example of this embodiment. It is a partial side sectional view showing a reinforcing bar joint of one embodiment concerning the present invention. BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing for connecting a reinforcing bar with the reinforcing bar joint of an example of this embodiment, (a) is a figure which shows the state which screwed the coupler in the thread part of one reinforcing bar, (b) is shown to (a). It is a figure which shows the state which made the edge part of the thread part of a reinforcing bar contact | abut the edge part of the thread part of the other reinforcing bar. It is a partial side sectional view showing a reinforcing bar joint of other examples of this embodiment.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of a reinforcing bar and a reinforcing bar joint according to the present invention will be described with reference to the accompanying drawings. As shown in FIG. 1, the reinforcing bar 1 of an example of this embodiment is used as a reinforcing bar that is a main reinforcing bar that serves as a beam or a column of reinforced concrete, and has a threaded portion 3 formed at the end. That is, the reinforcing bar 1 of this embodiment includes a reinforcing bar main body 2 and a screw portion 3. The reinforcing bar 1 (that is, the reinforcing bar main body 2) is not particularly limited as long as it is used as a reinforcing bar which is a main reinforcing bar that is a beam or column of reinforced concrete. For example, the diameter is 22.2 mm (the name of the reinforcing bar is D22), 25.4 mm. (Rebar name is D25), 28.6mm Rebar name is D29), 31.8mm (Rebar name is D32), 34.9mm (Rebar name is D35), 38.1mm (Rebar name is D38), 41.3mm ( Reinforcing bars whose name is D41) are used. Moreover, as the reinforcing bar 1 of this embodiment, as shown in FIG. 2, a deformed reinforcing bar having projecting portions such as a semicircular ridge and an axial ridge may be used.

  As shown in FIGS. 1 and 2, the screw portion 3 has a diameter larger than that of the rebar main body 2 and has a male screw 4 formed on the outer periphery. The threaded portion 3 is formed by first forming, at the end of the reinforcing bar main body 2, a thickened diameter-expanded portion that is larger in diameter than the reinforcing bar main body 2 by die forging that applies a compression force while performing high-frequency induction heating. In addition, it is preferable to obtain the male screw 4 by, for example, threading the outer periphery of the enlarged diameter portion.

  The male screw 4 is formed with 6 to 9 screw threads so that the reinforcing bar 1 can be connected with sufficient strength and the axial length of the screw part 3 can be shortened. When the number of threads of the male screw 4 is less than 6, the strength of the screw part 3 when the two reinforcing bars 1 are connected by screwing a coupler 11 (see FIG. 3), which will be described later, to the screw part 3 is rebar. When the number of threads of the male screw 4 exceeds 9, the axial length of the screw portion 3, that is, the range becomes wider, and the rebar 1 is connected using the coupler 11 This is because there may be an influence when arranging bars around the reinforcing bar 1.

In addition, the male screw 4 has a diameter d1 of the reinforcing bar main body 2 so that the length of the screw part 3 in the radial direction is short, that is, the height is low (if the reinforcing bar main body 2 is a deformed reinforcing bar, Ratio of valley diameter d3 (valley diameter) of male screw 4 to outermost diameter d2) (valley diameter d3 of male screw 4 / diameter d1 (d2) of rebar main body 2 (hereinafter referred to as d3 / d1)) is 1. It is formed by 05-1.50. d3 / d1 is preferably 1.10 to 1.30. If d3 / d1 is less than 1.05, the strength may be weaker than that of the reinforcing bar main body 2, or the two reinforcing bars may not be connected when the coupler 11 is used. On the other hand, if d3 / d1 exceeds 1.50, the height of the threaded portion 3 increases, and when the reinforcing bars are connected using the coupler 11, the reinforcing bars around the reinforcing bars may be affected. is there.

  The shape of the male screw 4 of the screw part 3 may be formed in any way as long as d3 / d1 is 1.05 to 1.50, but is formed based on the standard of JIS screw (coarse screw). It is preferable. Specifically, for example, in the D22 rebar, the threaded portion 3 is formed based on M30 (name of the screw), which will be abbreviated as follows: D33 is M33, D29 is M39, D32 is M42, D35 is M45, D38. Then, in M48 and D41, it is preferable that the screw portion 3 is formed based on M52, and the number of threads of the male screw 4 is 6 to 9, respectively.

  In this case, the cross-sectional area ratio (thread cross-sectional area / cross-sectional area) of the thread cross-sectional area to the rebar cross-sectional area when the number of threads of the M3 thread portion 3 is 6 with the D22 rebar is 2.6. When the number is 9, it is 3.9. Similarly, the cross-sectional area ratio in the case of the D25 rebar and the M33 screw part 3 is 2.1 when the thread number is 6, and 3.3 when it is 9. The cross-sectional area ratio of the D39 rebar and the M39 screw part 3 is 2.3 when the number of screw threads is 6, and 3.6 when 9. The cross-sectional area ratio in the case of the D32 rebar and the M42 screw part 3 is 2.2 when the number of threads is 6, and 3.5 when it is 9. The cross-sectional area ratio in the case of the D35 rebar and the M45 thread portion 3 is 2.0 when the number of threads is 6, and 3.1 when it is 9. The cross-sectional area ratio in the case of the D38 rebar and the M48 screw portion 3 is 2.0 when the number of threads is 6, and 3.1 when it is 9. The cross-sectional area ratio in the case of the D41 rebar and the M52 screw portion 3 is 1.8 when the number of threads is 6, and 2.8 when it is 9. From these, the cross-sectional area ratio is 1.8 or more, that is, the strength of the reinforcing bar body 2 is 1.8 times or more, so that the screw part 3 is screwed with the coupler 11 with sufficient strength than the reinforcing bar body 2 and You can connect.

  Further, the corner portion 5 at the boundary between the reinforcing bar body 2 and the screw portion 3 prevents stress from concentrating on the corner portion 5 at the boundary between the reinforcing bar body 2 and the screw portion 3 when tensile stress acts on the reinforcing bar 1. Therefore, it is preferable to form R. R is preferably formed by die forging, which is performed in order to form the screw part 3 by expanding the end of the reinforcing bar body 2 from the reinforcing bar body 2 in diameter. R is preferably formed with a diameter of 1 to 3 times the pitch of the male screw 4 of the screw portion 3, and particularly preferably with a diameter of 1.5 times the pitch of the male screw 4. If this R is less than 1 times the pitch of the male screw 4, stress will concentrate on the corner 5 of the boundary between the reinforcing bar body 2 and the screw part 3 when tensile stress acts on the connected reinforcing bars 1. This is because there is a possibility of breaking from the corner 5 as a result. On the other hand, if this R exceeds 3 times the pitch of the male screw 4, it becomes difficult to form R.

  Next, the reinforcing bar joint of this embodiment will be described. As shown in FIG. 3, the rebar joint 10 of this embodiment is connected using a coupler 11 in a state where two rebars 1 serving as beams and columns of such reinforced concrete are abutted against each other with screw portions 3 at the ends. To do. When the reinforcing bars 1 are attached together in this way, the spiral directions of the male threads 4 of the screw portions 3 of the two reinforcing bars 1 are the same as each other.

  The coupler 11 is formed in a cylindrical shape whose inner peripheral surface is circular. The shape of the outer peripheral surface of the coupler 11 may be circular, but is preferably a polygon, particularly preferably a polygon having a parallel opposite surface (such as a quadrangle, hexagon, or octagon). These are regular hexagons and regular octagons from the viewpoint of easy rotation of the coupler 11 with respect to the reinforcing bar 1 using a tool or the like. The outer shape of the coupler 11 is formed in the same shape over the entire axial length. The coupler 11 is not particularly limited as long as it is used for reinforced concrete. For example, a steel pipe is used, and specifically, a thick steel pipe may be cut for each screw cylinder length. Further, a steel pipe having a general thickness may be increased by a thickening process in which induction heating is performed while applying a compressive force, and the thickened steel pipe may be cut off.

  On the inner peripheral surface of the coupler 11, a female screw 12 that is screwed into the male screw 4 of the threaded portion 3 of the reinforcing bar is uniformly formed over the entire length by, for example, threading. The length in the axial direction of the coupler 11 is equal to or longer than the total length obtained by adding the lengths in the longitudinal direction of the screw portions 3 of the two reinforcing bars 1 connected by using the coupler 11 and is 15 mm longer than the total length. It is preferable to form the following. As a result, the reinforcing bars can be coupled with sufficient strength and the length of the coupler 11 in the axial direction can be shortened. This is because if the length of the coupler 11 in the axial direction is less than the total length, the two reinforcing bars may not be connected with sufficient strength, and the length of the coupler 11 in the axial direction is larger than the total length. This is because if the length exceeds 15 mm, the coupler 11 may affect the reinforcing bar arrangement around the reinforcing bars. In the example shown in FIGS. 3 and 4, the axial length of the coupler is formed as a total length, and in the example shown in FIG. 5, the axial length of the coupler is longer than the total length. Is formed. In FIG. 5, a line indicating the female screw of the coupler 11 is omitted so that the gap 13 between the one reinforcing bar 1 and the other reinforcing bar 1 can be easily understood.

  Further, when the two reinforcing bars 1 are connected to each other by the coupler 11, it is preferable that the slip amount between the two reinforcing bars 1 is 0.3 or less. Thereby, the tensile stress in a reinforced concrete can be borne by a reinforcing bar. If the amount of slip exceeds 0.3, the tensile stress in the reinforced concrete is borne by the rebar, but there is a possibility that the rebar is so large that the tensile stress cannot be absorbed by the rebar. is there. The amount of slip between the two reinforcing bars 1 can be reduced to 0.3 or less by accurately performing, for example, threading of the male screw 4 of the screw portion 3 and the female screw 12 of the coupler 11. .

Next, the case where the two reinforcing bars 1 are connected using the reinforcing bar joint 10 of the present embodiment will be described.
As shown in FIG. 4A, the coupler 11 is screwed onto the threaded portion 3 of one reinforcing bar so as to cover the outer periphery of the threaded portion 3. In this case, it is preferable that the coupler 11 is screwed into the screw portion 3 of one of the reinforcing bars 1 in advance. In this case, the coupler 11 is set so that the end surface of the screw portion 3 and the end surface of the coupler 11 are at the same position or close to each other. Thereby, since the screw part 3 of one rebar 1 is covered with the coupler 11, the screw part 3 of the rebar 1 can be protected when transporting and storing the construction site from the factory, and the screw. The protective member such as a cap for the portion 3 can be eliminated correspondingly, and dust can be reduced.

  As shown in FIG. 4A, the threaded portion 3 which is the end of the other reinforcing bar 1 connected to the reinforcing bar 1 is connected to the end of the reinforcing bar 1 screwed with the coupler 11 in this manner. For example, they are brought into contact with each other. In this state, the coupler 11 is rotated with respect to one reinforcing bar 1 and moved to the other reinforcing bar 1 side, and is screwed into the screw portion 3 of the other reinforcing bar 1. Thereby, two reinforcing bars can be connected via the coupler 11. At this time, since the length of the coupler 11 in the axial direction is not less than the total length and not more than 15 mm longer than the total length, the coupler 11 has a length that covers the screw portions 3 of the two reinforcing bars 1. 3 and FIG. 5, if the screw portion 3 of the two reinforcing bars 1 is hidden by the coupler 11 by visual observation, the two reinforcing bars 1 can be connected with sufficient strength. 11 can easily connect the two reinforcing bars 1 without requiring any special tools or skills. Therefore, the connection work can be simplified, the construction period can be shortened and the cost can be reduced, and the construction management can be facilitated.

  Further, as shown in FIG. 5, the coupler 11 is formed with a length longer than the total length, for example, 15 mm longer than the total length, so that the gap 13 between one reinforcing bar 1 and the other reinforcing bar 1 is 0 to 15 mm. As long as it is within the range, it can be arbitrarily selected. As a result, it is possible to adjust the position of the reinforcing bar 1 in the axial direction, and the connecting work of the reinforcing bar 1 is easy. Further, when the two rebars 1 are connected to each other by rotating the coupler 11 with respect to the rebar 1 while the two rebars 1 are attached to each other, the coupler 11 is screwed into the two rebars 1. Even if it rotates, the rebar 1 does not move in the axial direction unlike the turnbuckle type, so that the connection work is easier.

  In this way, by connecting the two reinforcing bars 1 using the coupler 11, the reinforcing bars 1 as the main reinforcing bars to be beams and columns can be easily arranged. When a reinforcing bar which is a reinforcing bar different from the main bar, such as a stirrup or a hoop bar, is disposed around the reinforcing bar 1 after the reinforcing bar 1 serving as the main bar is provided, the screw portion 3 protruding from the reinforcing bar body 2 is small. Therefore, it is possible to prevent the threaded portion 3 of the reinforcing bar 1 serving as the main reinforcing bar and particularly the coupler 11 from interfering with the reinforcing bar. That is, when the number of threads of the male thread 4 of the threaded portion 3 at the end of the reinforcing bar 1 as the main reinforcement is 6 to 9, the axial length of the threaded portion 3 can be shortened, that is, the range can be narrowed. it can. Moreover, when d3 / d1 is 1.05-1.50, the length of the radial direction of the screw part 3 can be shortened, that is, the height can be lowered. Accordingly, the rebar 1 can be connected using the coupler 11 with sufficient strength in the screw portion 3, and the range of the screw portion 3 protruding from the rebar main body 2 is narrow and the height is low. When the streak is disposed, the screw portion 3 and particularly the coupler 11 are less likely to get in the way. As a result, interference with the threaded portion 3 and particularly the reinforcing bar of the coupler 11 can be suppressed. Moreover, since the length of the coupler 11 can be shortened by forming the length of the coupler 11 in the axial direction to be 15 mm longer than the total length, interference with the reinforcing bar can be further suppressed.

  Further, by connecting the reinforcing bar 1 of the present embodiment by the reinforcing bar joint 10 of the present embodiment and arranging the reinforcing bars 1 and the reinforcing bars as the main reinforcing bars to be beams and columns, the concrete is placed. Reinforced concrete will be constructed. In this reinforced concrete, since the tensile stress is borne on the reinforcing bar 1, when the tensile stress acts on the reinforcing bar 1, it is possible to prevent the stress from being concentrated on the corner 5 of the boundary between the reinforcing bar body 2 and the screw part 3. There is no possibility of breakage due to stress concentration at the corner 5. Further, by forming R of the corner portion 5 by die forging, it is possible to prevent stress from being concentrated on the corner portion 5 further. That is, when R is formed by cutting, metal fibers are cut, and stress may concentrate at the cut portions. Further, by forming R with a diameter of 1 to 3 times the pitch of the external thread 4, it is possible to prevent stress from further concentrating on the corner 5 and particularly with a diameter of 1.5 times. By doing so, it is possible to more reliably prevent stress from concentrating on the corner 5.

  Further, when the two reinforcing bars 1 are connected to each other by the coupler 11, if the slip amount between the two reinforcing bars 1 is 0.3 or less, the tensile stress in the reinforced concrete can be borne by the reinforcing bar 1. The tensile stress of the reinforced concrete can be absorbed by the reinforcing bar 1.

DESCRIPTION OF SYMBOLS 1 Reinforcing bar 2 Reinforcing bar main body 3 Screw part 4 Male screw 5 Corner part 10 Reinforcement joint 11 Coupler 12 Female screw 13 Crevice

Claims (7)

Reinforcing bar that has a threaded part that is used as the main reinforcing bar of reinforced concrete, has a diameter that is larger than the reinforcing bar body at the end, and a male thread is formed on the outer periphery,
The number of threads of the male screw is 6-9,
A ratio of a root diameter of the male screw to a diameter of the reinforcing bar main body is 1.05 to 1.50.   The reinforcing bar according to claim 1, wherein a corner portion of a boundary between the screw portion and the reinforcing bar main body is formed in an R shape.   3. The reinforcing bar according to claim 2, wherein the R is formed by die forging performed to expand an end of the reinforcing bar body from the reinforcing bar body to form the screw part.   The reinforcing bar according to claim 2 or 3, wherein the R is formed with a diameter of 1 to 3 times the pitch of the male screw. A rebar joint for connecting two reinforcing bars according to any one of claims 1 to 4 using a coupler in a state in which ends thereof are butted against each other.
The spiral direction of the male thread of the two rebars is the same direction,
The coupler is formed in a cylindrical shape with a circular inner peripheral surface,
A rebar joint, wherein an internal thread that engages with the male thread is formed on an inner peripheral surface of the coupler.   The length in the axial direction of the coupler is not less than a total length obtained by adding the axial lengths of the thread portions of the two reinforcing bars and not more than 15 mm longer than the total length. Item 6. A reinforcing bar joint according to item 5. The reinforcing bar joint according to claim 5 or 6, wherein when the two reinforcing bars are connected by the coupler, a slip amount between the two reinforcing bars is 0.3 or less.

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