JP3735781B2 - Double bar spacer - Google Patents

Description

  The present invention relates to a double bar arrangement spacer that holds a plurality of reinforcing bars crossed in a lattice shape in a vertical relationship from a floor on which concrete is to be placed.

  Reinforced concrete obtained by crossing in a grid form in a formwork and arranging reinforcing bars at predetermined intervals, supported by spacers and spaced from the floor by a predetermined distance, and pouring concrete into the formwork is Widely used as structures such as objects and civil engineering structures. The above-mentioned reinforced concrete is a complementary relationship that reinforces concrete that is inferior in tensile stress with reinforcing steel that is excellent in tensile stress, and keeps reinforcing steel that is easily rusted in alkaline concrete in alkaline concrete, thereby preventing a decrease in strength due to rust of the reinforcing steel. It is in. In addition, the structure made of reinforced concrete has a compressive stress acting on the structure, and the rebar has a shearing or tensile stress. A suppressed structure can be obtained.

  In the reinforced concrete, the distance from the concrete surface to the surface of the reinforcing bar held by a spacer at a predetermined position in the concrete is called the “covering thickness” of the reinforcing bar. When the cover thickness of the reinforcing bar is insufficient, the concrete is easily peeled from the surface of the reinforcing bar, and moisture may enter from cracks caused by the peeling or the like, and the reinforcing bar may rust. Moreover, the concrete part of the reinforced concrete is neutralized over time from the outer surface due to carbon dioxide and acid rain in the air, and rust is likely to be generated in the reinforcing bars. Therefore, in the reinforced concrete, it is very important that the reinforcing bars are supported by spacers so that the reinforcing bars are held at a predetermined position in the concrete and kept at a predetermined cover thickness.

  Further, in the reinforced concrete, the reinforcing bars are arranged so that the distance between reinforcing bars arranged adjacent to each other in the X direction or the Y direction becomes a space defined by the design. That is, when the interval between certain reinforcing bars is narrowed, the interval between adjacent reinforcing bars becomes wide, and the reinforced concrete structure of this widened portion does not show the strength as designed. Therefore, in the reinforced concrete, in order to maintain the strength as a structural body, it is necessary to arrange the reinforcing bars arranged in the concrete at intervals as designed. The said reinforced concrete can improve the intensity | strength of a reinforced concrete structure by making it the so-called double reinforcement which piled up the reinforcement arranged in the shape of a lattice in two layers. In addition, in order to save the labor of reinforcing bars, there is also a welded reinforcing bar in which reinforcing bars are welded in a grid at regular intervals in a factory or the like.

  As shown in FIG. 7, general bar arrangement work is performed on the rebar 10 in the X direction and the Y direction on the discarded concrete or the dam plate (floor surface) placed for marking. Pitch division is performed to mark the reference marks for placing other reinforcing bars 10 (reinforcing bars 10 with marks are called pitch bars), and a plurality of reinforcing bars 10 are arranged at predetermined intervals in the XY direction with reference to the pitch bars. By arranging the bars, the lower reinforcing bars 12 located on the lower side made up of the plurality of reinforcing bars 10 intersecting in a lattice shape are formed. The intersecting portion 10a of the reinforcing bars 10 and 10 constituting the lower end reinforcing bar 12 is fastened by a thin metal wire called a binding wire (not shown) to fix the reinforcing bars 10 and 10 at different levels. In addition, a spacer 16 in which mortar or the like is formed in a dice shape is installed under the lower end stripe 12 at a predetermined interval, and the lower end reinforcement 16 is supported by the spacer 16 in a state of being separated from the floor surface by a predetermined interval. Then, after completion of the bar arrangement work of the lower end bars 12, the bar arrangement work of the upper end bars 14 located above the lower end bars 12 is performed. That is, the pitch dividing operation is performed in the same manner as the lower end bars 12, and a plurality of reinforcing bars 10 are arranged at predetermined intervals in the XY direction with reference to the pitch bars, so that the upper side composed of the plurality of reinforcing bars 10 intersecting in a lattice shape. The upper streak 14 located at the position is formed. The intersection 10 a of the reinforcing bars 10, 10 constituting the upper end bar 14 is fastened by a tie wire similarly to the lower end bar 12. Further, another spacer 18 formed in a trapezoidal shape by bending a reinforcing bar or the like is installed under the upper end bar 14, and the upper end bar 14 is supported by the spacer 18 in a state of being separated from the floor surface by a predetermined interval. In addition, it is configured to be separated from the lower end stripe 12 by a predetermined interval in a vertical relationship.

Since the lower end bars 12 and the upper end bars 14 are supported by different spacers 16 and 18 at different positions, the bottoms of the spacers 16 and 18 are exposed on the lower surface of the reinforced concrete structure, making it unsightly. It was. Accordingly, a spacer that supports the lower end stripe 12 and the upper end stripe 14 at the same position has been proposed (see, for example, Patent Document 1). In order to reduce the complicated and time-consuming work of pitching the reinforcing bars, a reinforcing bar holding device is also proposed that positions the reinforcing bars by providing concave parts at regular intervals in the belt-like holding member and fitting the reinforcing bars into the concave parts. (For example, see Patent Document 2).
JP-A-11-217906 Japanese Patent Laid-Open No. 9-13399

  The spacers 16 and 18 shown in FIG. 7 have a structure in which the reinforcing bar 10 is simply placed on the mounting surface and are not fixed. Therefore, vibration when concrete is laid and solidified using a vibrator, and flow during concrete placement. There is a concern that the position of the spacers 16 and 18 with respect to the reinforcing bar 10 is shifted by the pressure, and the predetermined cover thickness cannot be maintained. By the way, in the spacers disclosed in Patent Documents 1 and 2, the rebar movement restricting structure is configured to be simply inserted into the groove. When the operator moves over the reinforcing bar, such as the upper bar reinforcement, piping work such as electric piping that is driven into the reinforced concrete, or concrete placement work, the reinforcing bar is detached from the spacer. The problem will not be solved. In addition, the spacer disclosed in Patent Document 1 is configured to restrict movement in the left-right direction by inserting only the lower reinforcing bar of the reinforcing bars crossing the upper and lower steps into the groove, and restricting movement of both the reinforcing bars. Not what you want. That is, it is necessary to fix the crossing part of the reinforcing bar placed on the spacer with the binding wire, and it is pointed out that it is difficult to reduce the labor of binding the reinforcing bar.

  Moreover, in the bar arrangement process, in order to eliminate the trouble of the pitching operation of the bar arrangement, it is possible to use a welded reinforcing bar welded in advance in a lattice shape. However, the welded rebar is manufactured not in the bar arrangement site but in a factory, and is bulky, so it costs transportation, and in the case of the bar arrangement in a complicated shape, the yield is poor, which causes an increase in cost. . Further, the welded rebar has a drawback that the welded portion is easily rusted because the crossing portion of the rebar is connected by electric welding.

  That is, in view of the above-mentioned problems inherent in the conventional double bar arrangement spacer described above, the present invention has been proposed to suitably solve this problem, and saves the labor of binding the reinforcing bars and It is an object of the present invention to provide a double bar arrangement spacer that can easily perform the pitch dividing operation.

In order to overcome the above problems and achieve the intended purpose, the double bar arrangement spacer according to the present invention is:
A double bar arrangement spacer that holds a plurality of reinforcing bars crossed in a lattice shape in a vertical relationship from the floor on which concrete is to be placed,
A lower spacer that is placed on the floor and has a first concave groove at the upper end that accepts an intersection of reinforcing bars located on the lower side;
A second concave groove that can be attached to the lower spacer from above and that receives the crossing portion of the reinforcing bar located on the lower side is formed at the lower end, and a second groove that accepts the crossing portion of the reinforcing bar located on the upper side. It is characterized by comprising an upper adapter having three grooves formed at the upper end.

  According to the double bar arrangement spacer according to the present invention, on the lower spacer provided with the first concave groove for holding the lower reinforcing bar, the second concave groove for holding the lower reinforcing bar and the upper side. Since the upper adapter provided with the 3rd ditch | groove which hold | maintains the reinforcing bar located in is attached, and it was set as the structure which clamps a lower end reinforcement with a lower spacer and an upper adapter, the bottom part of a spacer is exposed to the lower surface of a reinforced concrete structure As a result, the binding work of the reinforcing bars located on the lower side can be reduced, and the displacement of the reinforcing bars can be prevented. Moreover, since the width | variety of each notch part which comprises the said 1st ditch | groove-the 3rd ditch | groove is set to the dimension which can insert one reinforcing bar compulsorily, it is hard to shift | deviate. Furthermore, since the depth of each notch part which comprises the said 1st ditch | groove-the 3rd ditch | groove is set more than the dimension which can accommodate two upper and lower rebars, since it becomes difficult to remove a rebar, crossing of a rebar It is not necessary to bind the parts, and the labor of binding the reinforcing bars located on the upper side can be reduced. Furthermore, by forming serrations that are offset and oriented in the direction in which the reinforcing bars are inserted in the respective incisions constituting the first to third concave grooves, the reinforcing bars are less likely to be disengaged from the spacer. The shift can be prevented.

  Since both ends of the bar-shaped member having a size matching the required bar arrangement pitch are fitted to the long grooves formed in the lower spacers adjacent in the X direction or the Y direction, the bars are arranged in a grid pattern. Reinforcing bar intersections can be easily indexed, and the labor of pitching work for complicated reinforcing bars can be reduced.

  The double bar arrangement spacer is formed by attaching an upper adapter having a second concave groove and a third concave groove from above to a lower spacer having a first concave groove that holds the lower end reinforcing bar. Configure to hold the upper streak. Also, in the long groove formed in the lower spacer, both ends of the rod-shaped member having a size matching the required bar arrangement pitch are fitted in the long groove of the lower spacer adjacent in the X direction or the Y direction so as to form a lattice shape. It is configured so that the intersections of the reinforcing bars to be arranged are indexed.

  Next, the double bar arrangement spacer according to the present invention will be described below with reference to preferred examples. As shown in FIG. 1, the double bar arrangement spacer 20 is attached to the lower spacer 22 that supports the lower end bars 12 at a predetermined interval from the floor, and the upper part of the lower spacer 22. Basically, the upper adapter 42 is supported at a predetermined interval from 12. Here, the bottom bar 12 refers to a group of reinforcing bars located on the lower side in a plurality of reinforcing bars (double bar arrangement) crossed in a lattice shape held in a vertical relationship, whereas the upper bar 14 is the upper bar. This refers to a reinforcing bar group located above the lower end reinforcement 12 and spaced apart by a predetermined distance.

  As shown in FIG. 1 or FIG. 2, the lower spacer 22 is a cylindrical hollow body having both ends open, and has a trumpet-shaped flange portion 25 bent at one end (lower end) outward. The provided short pipe is used as the main body portion 24, and a material such as metal or resin is employed. And the 1st ditch | groove 26 which receives the cross | intersection part 10a of the reinforcing bars 10 and 10 which comprise the lower end reinforcement 12 is opened in the other end part (upper end) of the said main-body part 24. As shown in FIG. The first concave groove 26 includes four cut portions 26a that are recessed at a central angle of approximately 90 degrees from the upper end surface of the main body 24 toward the lower end surface where the flange portion 25 is formed. The width of the cut portion 26a is set to a size that allows the single reinforcing bar 10 to be forcibly inserted. Further, the depth of the notch 26a (the dimension from the upper end surface of the lower spacer 22 to the bottom of the notch 26a) is more than the dimension that can accommodate the two reinforcing bars 10 and 10 that intersect in a vertical direction. Is set. In addition, since the diameter of the reinforcing bar 10 employ | adopted by design strength or a reinforcement arrangement | positioning site | part etc. differs, the width | variety and depth of each cutting part 26a are adjusted according to the diameter of the reinforcing bar 10 made into object. In the first concave groove 26, one rebar 10 is inserted over the cut portions 26a, 26a facing in the X direction, and the other rebar 10 is formed over the cut portions 26a, 26a facing in the Y direction. Is inserted, and the intersecting portion 10a of the reinforcing bars 10 and 10 combined in a vertical direction is sandwiched by the first concave groove 26 of the lower spacer 22 to form the lower end stripe 12.

  As shown in FIG. 1 (a), the lower spacer 22 supports the held lower end stripe 12 while being separated from the floor surface by a distance from the lower end surface of the main body 24 to the bottom of each of the cut portions 26a. It is configured as follows. By the way, in the lower end reinforcing bar 12, the cover thickness formed by the lower reinforcing bar 10 and the floor surface in the reinforcing bars 10 and 10 crossing the upper and lower steps is defined by a building standard law or a specification or the like depending on a part to be used. Accordingly, in the lower spacer 22, the cover thickness of the lower end stripe 12 is adjusted by adjusting the distance between the lower end surface of the main body 24 and the bottom of each notch 26 a (the size of the main body 24). It is suitably set according to.

  Further, in the main body 24 of the lower spacer 22, serrations 27 that are oriented to be offset in the direction in which the reinforcing bars 10 are inserted in the both side walls facing the notches 26 a of the first recessed grooves 26 formed in the recess. Is formed. The serration 27 is composed of a plurality of projecting pieces 27a projecting inwardly of the notch portions 26a on both side wall portions, and each projecting piece 27a is formed over the side wall portion in the vertical direction. It is serrated. The protruding piece 27a has a substantially right triangle shape, and the right angle portion of the substantially right triangle shape faces the side wall portion, the oblique side faces upward, and the tip portion of the protruding piece 27a is biased downward. It has become.

  The upper adapter 42 is a cylindrical hollow body whose both ends are open, and a short pipe formed so as to be coaxially attached from above the lower spacer 22 is used as a main body portion 44. For example, metal or resin is used. The material is adopted. The lower end of the main body 44 is provided with a second concave groove 46 for receiving the intersecting portion 10a of the reinforcing bars 10 and 10 constituting the lower end reinforcement 12, and the upper end 14 is provided at the upper end of the main body 44. A third concave groove 48 for receiving the intersecting portion 10a of the reinforcing bars 10 and 10 is formed. The second concave groove 46 is composed of four cut portions 46a that are recessed at a central angle of approximately 90 degrees from the lower end surface of the main body portion 44 upward, and the third concave groove 48 is the main body portion. It is composed of four cut portions 48a that are recessed from the upper end surface of 44 at a central angle of approximately 90 degrees. The cut portions 46a of the second concave groove 46 and the cut portions 48a of the third concave groove 48 are recessed so as to be positioned vertically symmetrically. Moreover, the width | variety of each notch part 46a, 48a is set to the dimension which can insert one reinforcing bar 10 compulsorily. Further, the depth of each of the cut portions 46a and 48a is set to be larger than the dimension capable of accommodating the two reinforcing bars 10 and 10 that intersect in a vertical direction. The depth of the cut portion 46 a of the second concave groove 46 is a dimension from the lower end surface of the main body portion 44 to the bottom portion of the cut portion 46 a in the upper adapter 42, and the depth of the cut portion 48 a of the third concave groove 48. Is a dimension from the upper end surface of the main body 44 in the upper adapter 42 to the bottom of the cut portion 48a. In addition, since the diameter of the reinforcing bar 10 employed differs depending on the design strength, the reinforcing bar location, and the like, similarly to the notch 26a of the lower spacer 22, each notch 46a, 48a is matched to the diameter of the target reinforcing bar 10. The width and depth are adjusted.

  As shown in FIG. 1 (b), the upper adapter 42 is extrapolated to the lower spacer 22 holding the lower end stripe 12, and each notch 46 a constituting the second groove 46 is inserted into the lower end stripe 12. Then, the cut portions 46a and the cut portions 26a of the first concave groove 26 are placed on the lower spacer 22 in a state where the intersecting portions 10a of the reinforcing bars 10 and 10 are sandwiched. One reinforcing bar 10 is inserted over the cut portions 48a, 48a facing the Y direction of the third concave groove 48, and the other reinforcing bar 10 is inserted over the cut portions 48a, 48a facing the X direction. The intersecting portion 10a of the reinforcing bars 10 and 10 that are inserted and intersected in the vertical direction is sandwiched between the third concave grooves 48 of the upper adapter 42 to form the upper end rebar 14.

  The upper bar 14 held by the upper adapter 42 is defined by the distance from the lower bar 12 to the cover thickness formed by the upper reinforcing bar 10 and the finished surface of the reinforced concrete in the reinforcing bars 10, 10 crossing the upper and lower steps. The Therefore, by adjusting the axial dimension of the main body 44 in the upper adapter 42, it is set so as to have a suitable cover thickness.

  Further, in the main body portion 44 of the upper adapter 42, the direction in which the reinforcing bars 10 are inserted into both side wall portions facing the cut portions 46 a and 48 a of the second concave groove 46 and the third concave groove 48 that are provided in a recessed manner. Serrations 47 and 49 are formed that are offset and oriented. The serrations 47 and 49 are formed from a plurality of projecting pieces 47a and 49a projecting inwardly of the notches 46a and 48a on the both side wall portions in the same manner as that formed in the first concave groove 26. Thus, each of the projecting pieces 47a and 49a is formed in the vertical direction of the side wall portion and has a sawtooth shape. The projecting piece 47a formed in the second concave groove 46 has a substantially right triangle shape, the right angle portion of the substantially right triangle shape faces the side wall portion, and the hypotenuse faces downward, that is, the tip portion is upward. It is formed in a biased state. On the other hand, the projecting piece 49a formed in the third concave groove 48 has a substantially right triangle shape, and the right angle portion of the substantially right triangle shape faces the side wall portion, and the hypotenuse faces upward. The tip is formed in a state of being biased downward. The serration 49 of the third concave groove 48 is formed symmetrically with the serration 47 of the second concave groove 46.

  A long groove 28 is formed at the bottom of each notch 26a in the first groove 26 provided in the lower spacer 22 and is set smaller than the width of the notch 26a and further recessed downward. ing. And the rod-shaped member 30 set to the dimension according to a required bar arrangement pitch is comprised so that it may fit correspondingly to the said long groove 28 of the lower spacer 22 adjacent to a X direction or a Y direction (FIG. 3). The rod-shaped member 30 is a metal round bar, and at both ends thereof, groove-shaped locking portions 30a and 30a are provided in a recessed manner over the entire circumference at portions spaced from each end face by a predetermined distance. The locking portion 30a is fitted into the long groove 28 of the lower spacer 22, and the adjacent lower spacers 22 and 22 are held in a state of being separated by a predetermined interval in the horizontal direction.

  Next, the operation of the double bar arrangement spacer according to the first embodiment will be described. Therefore, a reinforcing bar arranging operation using the spacer of Example 1 will be briefly described. First, the lower spacer 22 is placed at a required position on the floor surface with the flange portion 25 facing downward (see FIG. 4A), and is opposed to the X direction in the first concave groove 26 formed at the upper end. One of the reinforcing bars 10 is forcibly inserted into and fixed to the notches 26a and 26a. Next, the other rebar 10 is forcibly inserted into the notches 26a and 26a facing in the Y direction in the first concave groove 26, so that the intersecting portion 10a of the two rebars 10 and 10 combined up and down. And the intersection 10a is held from the floor with a predetermined cover thickness (see FIG. 4B). By performing this operation at the installation position of the lower spacer 22 set in accordance with a required bar arrangement pitch, the reinforcing bars 10 and 10 are arranged in a lattice shape and the lower end bar 12 is formed. Then, the lower end stripe 12 is aligned with the lower spacer 22 received in the first concave groove 26, and the notches 46 a of the second concave groove 46 in the upper adapter 42 are aligned with the notches 26 a of the first concave groove 26. In this state, the reinforcing bars 10 and 10 constituting the lower end reinforcement 12 are forcibly inserted into the respective cut portions 46a of the second concave groove 46 by being coaxially attached from above (see FIG. 4C). Finally, in the third concave groove 48 formed at the upper end of the upper adapter 42, one of the reinforcing bars 10 is forcibly fitted and fixed to the notches 48a and 48a facing in the Y direction. Then, by forcibly inserting the other reinforcing bar 10 into the notches 48a, 48a facing in the X direction, the movement of the intersecting portion 10a of the two reinforcing bars 10, 10 combined in a vertical difference is regulated, and the floor The intersecting portion 10a is held at a predetermined height from the surface (see FIG. 4D). By performing this operation for each of the lower spacers 22, the upper reinforcing bars 14 in which the reinforcing bars 10 are arranged in a lattice shape are formed above the lower reinforcing bars 12 at a predetermined interval, and the upper reinforcing bars 14 are formed. The cover thickness between the reinforcing bars 10 and 10 and the finished surface of the concrete is appropriately maintained (see FIG. 3).

  In the bar arrangement work of the lower end bars 12, the pitch division work of the reinforcing bars 10 and 10 adjacent in the X direction or the Y direction is performed as follows. As shown in FIG. 3, prior to fitting the lower end stripe 12 into the first concave groove 26 of the lower spacer 22 placed on the floor surface, the long groove 28 of the lower spacer 22 is formed at one end of the rod-like member 30. The engaging portion 30 a formed is fitted, and the engaging portion 30 a formed at the other end is then fitted into the long groove 28 of another lower spacer 22, and the rod-shaped member 30 is interposed between the adjacent lower spacers 22, 22. Hang over. Thereby, a pair of adjacent lower spacers 22 and 22 are arranged in a state of being separated by the dimension of the rod-shaped member 30. Then, by inserting the rod-shaped members 30 into the respective long grooves 28 so that another lower spacer 22 is disposed adjacent to the X direction or Y direction of the lower spacer 22, each of them is arranged at regular intervals in a grid pattern. A lower spacer 22 is installed. That is, since the rod-shaped member 30 is set to a size (three pitches in the embodiment) according to a predetermined bar arrangement pitch, each lower spacer 22 is located at the intersection 10a of the reinforcing bars 10 and 10. Become. Therefore, the reinforcing bars 10 are inserted into the lower spacers 22 so that the bars are arranged in accordance with a predetermined bar arrangement pitch (three pitches in the embodiment). A predetermined number of reinforcing bars 10 are allocated between the lower spacers 22 and 22 to form the lower end bars 12. Thus, by defining the spacing between the lower spacers 22 and 22 adjacent to each other in the X direction or the Y direction with the rod-shaped member 30, it is possible to save the trouble of indexing the intersections of the reinforcing bars 10 arranged in a lattice shape. it can. It should be noted that the bar arrangement work can be further facilitated by providing marks on the rod-shaped member 30 in advance according to the bar arrangement pitch.

  Moreover, the minimum number of arrangement | positioning per area is defined for the arrangement | positioning number of the said spacer 20 for double bar arrangement | positioning by a building standard law or a specification. That is, by setting the size of the bar-shaped member 30 in accordance with the number of bar arrangement pitches that satisfies the minimum arrangement number, the arrangement number of the double bar arrangement spacers 20 is necessarily satisfied. The trouble of managing the 20 arrangement intervals is reduced.

  In addition, by setting the bar-shaped member 30 to one pitch of the reinforcing bar, the lower spacers 22 and 22 adjacent in the X direction or the Y direction are arranged with one pitch separation, and the lower spacer The adjacent reinforcing bars 10 and 10 held by 22 and 22 are separated at a designed interval. Therefore, it is possible to further reduce the labor of the pitching operation of the reinforcing bars and to reliably satisfy the required design strength because the adjacent reinforcing bars 10 and 10 are reliably held at a predetermined interval. .

  In the double bar arrangement spacer 20 of the first embodiment, an upper adapter 42 is attached on the lower spacer 22 having the lower end stripe 12 received in the first concave groove 26, and the third concave groove 48 of the upper adapter 42 is attached. By receiving the top muscle 14, the bottom muscle 12 and the top muscle 14 are held in a vertical relationship. That is, since the upper adapter 42 that holds the upper bar 14 is provided at the same position as the lower spacer 22 that holds the lower bar 12 and is attached to the lower spacer 22, a reinforced concrete structure such as a floor slab. It is possible to reduce the bottom portion of the double bar arrangement spacer 20 exposed on the lower surface of the frame. Further, the upper adapter 42 is attached so that the lower stripe 12 received in the first groove 26 of the lower spacer 22 is received by the second groove 46 formed at the lower end of the upper adapter 42. Therefore, the lower end stripe 12 is sandwiched between the first concave groove 26 and the second concave groove 46. That is, since the lower end bar 12 is restricted not only in the horizontal direction but also in the vertical direction by the double bar arrangement spacer 20, it is not necessary to bind the intersection 10 a of the reinforcing bars 10, 10, and complicated binding work is performed. Can be reduced. Even when the upper end reinforcement 14 is laid, when the concrete is laid and solidified using a vibrator, or when fluid pressure during concrete placement acts as a load on the lower end reinforcement 12, the lower end reinforcement 12 An appropriate cover thickness can be maintained without deviating from the double bar arrangement spacer 20.

  By setting the width of each of the cut portions 26a, 46a, 48a constituting the first to third concave grooves 26, 46, 48 to a size that allows the single reinforcing bar 10 to be forcibly inserted, In addition to restricting movement, it also makes it difficult to move in the vertical direction. Further, by setting the depth of each of the cut portions 26a, 46a, 48a constituting the first to third concave grooves 26, 46, 48 to a size that can accommodate the two upper and lower reinforcing bars 10, 10, It is possible to restrict the movement of both the reinforcing bars 10 and 10 intersecting the upper and lower reinforcing bars 12 and 14 at different levels. Furthermore, by forming serrations that are offset and oriented in the direction in which the reinforcing bars 10 are inserted into the notches 26a, 46a, 48a, when inserting the reinforcing bars 10 into the notches 26a, 46a, 48a, The rebar 10 can be forcibly inserted along the oblique sides of the protrusions 27a, 47a, 49a of the serrations 27, 47, 49. On the other hand, when removing the reinforcing bar 10 from the first to third concave grooves 26, 46, 48, it is horizontal with the reinforcing bars 10 of the projecting pieces 27a, 47a, 49a constituting the serrations 27, 47, 49. Opposite sides are caught by the reinforcing bar 10 and the upward movement of the reinforcing bar 10 is restricted. Accordingly, the upper end bars 14 inserted into the respective cut portions 48a constituting the third concave groove 48 opened at the upper side are disengaged from the spacer 20 even when a load such as a flow pressure of concrete is applied. And an appropriate cover thickness can be maintained. As described above, the crossing portion 10a of the reinforcing bars 10 and 10 received by the lower spacer 22 and the upper adapter 42 is restricted from moving not only in the horizontal direction but also in the vertical direction. Therefore, the bundling of the intersecting portion 10a can be omitted, and the labor of complicated bundling work can be reduced.

  FIG. 5 shows a double bar arrangement spacer 50 according to the second embodiment, and the configuration thereof is basically the same as the double bar arrangement spacer 20 according to the first embodiment described above. Explanation of elements is omitted. The lower spacer 52 is a rectangular tube-shaped hollow body whose both ends are open, and a main body portion 54 provided with a leg portion 58 at one end (lower end) is made of, for example, a resin. A first concave groove 56 is formed in the other end (upper end) of the main body 54 to receive the intersecting portion 10 a of the reinforcing bars 10, 10 constituting the lower end rebar 12. The upper adapter 62 is a rectangular tube-shaped hollow body whose both ends are open, and a main body portion 64 formed so as to be insertable from above the lower spacer 52 is made of, for example, resin. The lower end of the main body portion 64 is provided with a second concave groove 66 for receiving the intersecting portion 10a of the reinforcing bars 10 and 10 constituting the lower end reinforcement 12, and the upper end of the main body portion 64 is provided with the upper end reinforcement 14. The 3rd ditch | groove 68 which receives the cross | intersection part 10a of the reinforcing bars 10 and 10 which comprise is opened. Since the configuration of each of the cut portions 56a, 66a, 68a of the first to third concave grooves 56, 66, 68 is the same as that of the first embodiment, the description thereof is omitted. The double bar arrangement spacer 50 according to the second embodiment provides the leg portion 58 in the lower spacer 52 in addition to the effects described in the double bar arrangement spacer 20 of the first embodiment. It becomes easy to go around the inside of the main body portion 54 and it becomes difficult to retain air. Although not shown, each of the four cut portions 56a constituting the first concave groove 56 is provided with a long groove extending below the lower spacer 52, and has a size that matches the required bar arrangement pitch. Both ends of the rod-like member are fitted in correspondence with the long grooves of the lower spacers 52 adjacent to each other in the X direction or the Y direction so that the intersections of the reinforcing bars 10 arranged in a lattice shape are indexed. A configuration may also be employed.

  In the first embodiment, in the double bar arrangement, the intersections of the reinforcing bars 10 arranged in a lattice shape are determined by spanning the rod-shaped member 30 between the lower spacers 22 and 22 adjacent in the X direction or the Y direction. However, it can be adopted even in single reinforcement. That is, as shown in FIG. 6, prior to fitting the lower end stripe 12 into the first concave groove 26 of the lower spacer 22 placed on the floor, one end of the rod-shaped member 30 is inserted into the long groove 28 of the lower spacer 22. The engaging portion 30a formed on the other end is fitted, and the engaging portion 30a formed on the other end is fitted into the long groove 28 of another lower spacer 22, and the rod-like shape is interposed between the adjacent lower spacers 22,22. It spans over the member 30. Thereby, a pair of adjacent lower spacers 22 and 22 are arranged in a state of being separated by the dimension of the rod-shaped member 30. Then, by inserting the rod-shaped members 30 into the respective long grooves 28 so that another lower spacer 22 is disposed adjacent to the X direction or Y direction of the lower spacer 22, each of them is arranged at regular intervals in a grid pattern. A lower spacer 22 is installed. Then, one reinforcing bar 10 is forcibly inserted and fixed in the notches 26a and 26a facing in the X direction in the first concave groove 26, and the other reinforcing bar 10 is forcibly inserted in the notches 26a and 26a facing in the Y direction. As a result, the movement of the intersecting portion 10a of the two reinforcing bars 10 and 10 combined in a vertical difference is restricted, and the intersecting portion 10a is held with a predetermined cover thickness from the floor surface. As described above, even in the single bar arrangement, the crossing of the reinforcing bars 10 arranged in a lattice shape can be easily performed by spanning the rod-shaped member 30 between the adjacent lower spacers 22 and 22. It is possible to reduce the labor of pitch division work.

The spacer for double bar arrangement concerning preferred Example 1 of the present invention is shown, (a) is a front view showing a separation state, and (b) is a front view showing a use state. 3 is a schematic perspective view showing a double bar arrangement spacer of Example 1. FIG. It is a schematic perspective view which shows the use condition of the spacer for double bar arrangement of Example 1. FIG. It is a schematic perspective view which shows the assembly process of the spacer for double bar arrangement of Example 1. FIG. FIG. 6 shows a double bar arrangement spacer according to Example 2, (a) is a schematic perspective view showing a separated state, and (b) is a schematic perspective view showing a use state. It is a schematic perspective view which shows the use condition of the lower spacer which concerns on Example 3. It is a schematic perspective view which shows the use condition of the conventional spacer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Reinforcing bar 10a Intersection 22 Lower spacer 26 First concave groove 26a Cut portion 27 Serration 28 Long groove 30 Bar-shaped member 42 Upper adapter 46 Second concave groove 46a Cut portion 48 Third concave groove 47 Serration 48a Cut portion 49 Serration

Claims (8)

A double bar arrangement spacer that holds a plurality of reinforcing bars (10, 10) crossed in a lattice shape in a vertical relationship from the floor on which concrete is to be placed,
A lower spacer (22) placed on the floor and having a first concave groove (26) at the upper end for receiving an intersection (10a) of reinforcing bars (10, 10) located on the lower side;
A second concave groove (46) that can be attached to the lower spacer (22) from above and receives the intersection (10a) of the lower reinforcing bars (10, 10) is formed at the lower end. In addition, a double bar arrangement characterized by comprising a third concave groove (48) for receiving the intersection (10a) of the upper reinforcing bars (10, 10) and an upper adapter (42) opened at the upper end. Spacer.   The lower spacer (22) is formed of a hollow body, and the first concave groove (26) is formed by four cut portions (26a) that are recessed at a central angle of about 90 degrees on the upper end surface of the lower spacer (22). The double reinforcing bar spacer according to claim 1.   The upper adapter (42) is a hollow body that can be attached to the lower spacer (22), and the second concave groove (46) has a central angle of approximately 90 degrees on the lower end surface of the upper adapter (42). The double bar arrangement spacer according to claim 2, comprising four cut portions (46 a) provided in a recessed manner.   The double reinforcing bar spacer according to claim 3, wherein the third concave groove (48) is composed of four cut portions (48a) that are recessed at an upper end surface of the upper adapter (42) at a central angle of about 90 degrees.   The widths of the notches (26a, 46a, 48a) constituting the first to third grooves (26, 46, 48) are dimensioned so that a single reinforcing bar (10) can be forcibly inserted. The spacer for double bar arrangement according to claim 4 which is set up.   The depths of the notches (26a, 46a, 48a) constituting the first to third grooves (26, 46, 48) are dimensions that can accommodate the upper and lower two reinforcing bars (10, 10). The double bar arrangement spacer according to claim 5, which is set as described above.   Serrations that are offset and oriented in the direction in which the reinforcing bars (10) are inserted into the notches (26a, 46a, 48a) constituting the first to third grooves (26, 46, 48). 27, 47, 49) The double bar arrangement spacer according to claim 6. Each of the four notches (26a) constituting the first concave groove (26) is provided with a long groove (28) extending downward from the lower spacer (22), and the size is adjusted to a required bar arrangement pitch. Both ends of the rod-shaped member (30) are fitted into the long grooves (28) of the lower spacer (22) adjacent in the X direction or the Y direction, and the reinforcing bars (10, The double bar arrangement spacer according to claim 2, wherein the intersection indexing of 10) is performed.

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