JP4756680B2 - Reinforced concrete spacer - Google Patents

Description

  The present invention relates to a reinforced concrete spacer for maintaining a predetermined distance between a reinforcing bar and a formwork disposed outside the reinforcing bar when a reinforced concrete structure is constructed.

  In general, when constructing a reinforced concrete structure such as a slab of a building or a bridge girder of an expressway, a spacer used for securing a concrete cover between the reinforcing bar and the structure or formwork is, for example, FIG. The configuration is as shown in FIG.

  FIG. 11 shows an example of a resin-made reinforcing bar spacer 51 made of resin, in which a reinforcing bar support 53 is formed at the center of the spacer main body 52, and the outer peripheral surface of the reinforcing bar support 53 and the inner peripheral surface of the spacer main body 52. A plurality of ribs 54 are continuously provided between them.

  A space 56 is formed between a pair of reinforcing ribs 55 provided in the lower half of the spacer body 52, and a reinforcing bar introduction passage 59 formed between the opposing surfaces is formed at the lower end of the opening of the space 56. The lower end portions of the pair of reinforcing bar support arms 57 and 57 are continuously provided so as to be gradually narrowed, and the reinforcing bar insertion hole portion 58 is formed between the upper end of the reinforcing bar support arms 57 and 57 and the reinforcing bar support portion 3. The reinforcing bar spacer 51 for building is formed integrally with large diameter reinforcing bar receiving pieces 57a and 57a for sandwiching a large diameter reinforcing bar together with the reinforcing bar supporting part 53 at the upper ends of the reinforcing bar supporting arms 57 and 57, and the large diameters thereof. A small-diameter reinforcing bar receiving piece 57b for sandwiching a small-diameter reinforcing bar with the reinforcing bar support 53 is integrally formed with the reinforcing bar receiving pieces 57a and 57a (see Patent Document 1).

  FIG. 12 shows another example, in which the fastening string 62 is fixed inside the concrete spacer body 61 in a state where a part of the fastening string 62 is inserted. It is made of a material such as a synthetic resin having rust resistance and has a large number of small concave and convex portions 63 for retaining over almost the entire length, and the small concave and convex portions 63 are inserted into one side end portion. It is assumed that the retaining latching portion 64 that can be secured has a tapered portion 66 for insertion into the hole 65 of the latching portion 64 at the other end, and the portion of the fastening cord 62 near the latching portion 64 is provided. The spacer body 61 is molded and fixedly inserted into a mold at the time of molding. A hook piece 67 is formed in the hole 65 of the hook portion 64 so as to be able to reverse the shape corresponding to the shape of the small concavo-convex portion 63. The spacer main body 61 can be fixed (see Patent Document 2).

  FIGS. 13 and 14 show different examples, including a spacer block 71 made of concrete and a reinforcing bar support arm 72 made of one spring metal wire, and the spacer block 71 has a substantially flat base surface 73, From this, a ring-shaped embedded anchor 75 which is raised by the cover thickness T of the reinforcing bar to form a top surface 74 which comes into contact with the weir plate of the mold for forming a concrete structure, while being bent at the intermediate part of the reinforcing bar supporting arm 72. Are embedded and integrated into the central portion of the base surface 73 in the spacer block 71, and a pair of straight bars 76a that cross from the embedded anchor 75 along the plane of the base surface 73 non-perpendicularly with the longitudinal axis of the reinforcing bar. , 76b is extended linearly in the opposite direction, and both straight bars 76a, 76b are extended. A pair of substantially parallel locking hooks 77a and 77b extending from the end portion in the direction opposite to the direction of the embedded anchor 75 and being substantially perpendicular to the longitudinal axis of the reinforcing bar and sandwiching the circumferential surface of the reinforcing bar from the opposite direction; When the rebar support arm 72 is twisted and rotated by applying the rebar support arm 72 so that the bent leading ends of the lock hooks 77a and 77b are in contact with the circumferential surface of the rebar, the both lock hooks 77a. , 77b is determined so as to elastically bite into the circumferential surface of the reinforcing bar.

  When this spacer is actually used, as shown in FIG. 14, both the straight bars 76a and 76b of the reinforcing bar supporting arm 72 of the spacer block 71 greatly intersect with the longitudinal axis of the reinforcing bar P, and both locking hooks 77a are also used. , 77b, the spacers are applied to the reinforcing bar P so that the insertion guides 78a, 78b at the bent leading ends thereof come into contact with the circumferential surface of the reinforcing bar P from the opposite direction. By twisting and rotating the spacer in the direction of the arrow, both the locking hooks 76a and 76b are locked in a state of being inserted into the circumferential surface of the reinforcing bar P (see Patent Document 3).

  15 and 16 show still another example, in which a metal rod-like body 82 is embedded in a concrete spacer body 81 in a state where both ends thereof are exposed from both side surfaces of the spacer body 81. The spacer main body 81 is arranged at the intersection of the vertical reinforcing bar 83 and the horizontal reinforcing bar 84 which are substantially orthogonal to each other, and the spacer main body 81 is fixed to the vertical and horizontal reinforcing bars 83 and 84 by the wire 85 using the exposed portion of the rod-like body 82. The tip of the spacer body 81 is held in contact with the inner surface of the formwork W, and the cover allowance of the concrete K is ensured (Patent Document 4 [Description of article related to design] and usage state) Refer to the reference diagram).

JP 2001-132166 A (paragraphs [0013] to [0017] and FIG. 1) JP 2001-173159 A (paragraphs [0014] to [0022] and FIG. 3) Japanese Patent No. 2872999 (paragraphs [0012] to [0025], [0030], [0031] and FIGS. 1, 13, and 14) Design Registration No. 1198802 ([Description of Articles Related to Design], Reference Diagram showing Usage Status)

  However, in the case of the example shown in FIG. 11, the spacer can be easily attached to the reinforcing bar, and the attached spacer does not shift or come off even when vibration is applied by a vibrator to evenly flow the concrete. However, since the spacer is made of resin, the spacer is not compatible with concrete and may cause partial peeling of the concrete.

  In the example shown in FIG. 12, even if the spacer main body 61 is made of concrete, the fastening string 62 is made of resin. There is a risk of partial peeling of concrete due to lack of affinity with concrete.

  On the other hand, in the case of the example shown in FIGS. 13 and 14, unlike the case of FIG. 11 and FIG. 12 described above, since there is no resin portion, the affinity with concrete is good, and there is no risk of causing partial peeling of the concrete, Since both the locking hooks 77a and 77b are inserted into the circumferential surface of the reinforcing bar P and locked by the elastic force, the elastic force of the both locking hooks 77a and 77b is insufficient. Then, when vibration is applied by a vibrator for evenly pouring the concrete, the locking of both locking hooks 77a and 77b is loosened and the spacer is removed, resulting in the inconvenience that the concrete cover is not as specified. obtain.

  A structure in which a pair of metal hook bodies having spring properties are embedded in a concrete block and a reinforcing bar is sandwiched between both hook bodies has been proposed in the past, but is similar to the above-described examples of FIGS. There's a problem.

  Further, in the case of the examples shown in FIGS. 15 and 16, as in the case of FIGS. 13 and 14, since there is no resin portion and the affinity with concrete is good, there is no possibility of causing partial peeling of the concrete, but the wire 85 is used. The spacer main body 81 is fixed by being wound around the vertical and horizontal reinforcing bars 83 and 84 and the exposed portions of the rod-shaped body 82. To firmly fix the spacer main body 81 so that the spacer main body 81 is not displaced by vibration caused by a vibrator when concrete is poured. There is a peculiar problem that the winding work of the wire 85 requires skill.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a spacer that is excellent in affinity with concrete, can be easily attached, and does not come off due to vibration caused by a vibrator during pouring of concrete.

In order to solve the above-described problem, the reinforced concrete spacer according to claim 1 maintains a predetermined distance between the reinforcing bar and the formwork disposed outside thereof when constructing the reinforced concrete structure. Reinforced concrete spacers for maintaining the cover allowance of concrete, and a block made of concrete for securing the cover allowance, and having a substantially U shape or substantially U shape, and fixing the block body to the rebar And a bolt for sandwiching the reinforcing bar inside the tightening member, the bolt is embedded in the block body, and the bolt is screwed into the tightening member. is formed a female screw portion for engagement is the fastening member is formed by folding or bending a metal plate, base and, paired each other with a slightly larger becomes spacing than the diameter of the reinforcing bar The female screw portion is one of the opposing pieces, and is located at a distance greater than the diameter of the reinforcing bar from the inner position of the base where the reinforcing bar can come into contact. The block body is fixed to the reinforcing bar by being formed and screwed with the female screw part of the bolt so as to sandwich the reinforcing bar between the inner surface of the fastening member and the tip part of the bolt. .

Moreover, in the spacer for reinforced concrete according to claim 2 , the bolt is embedded in one end face of the block body, and when screwed with the female screw portion, a length corresponding to half or more of the diameter of the reinforcing bar, The length is set so that it may protrude inside the said fastening member.

In the reinforced concrete spacer according to claim 3 , the other facing piece of the fastening member is shorter than the one facing piece and contacts the reinforcing bar when screwed with the female thread portion of the bolt. It is characterized by being set to a possible length.

The spacer for reinforced concrete according to claim 4 is characterized in that a nut having a predetermined thickness is screwed to the bolt.

In the reinforced concrete spacer according to claim 5 , the cover allowance is a total of at least a length from one end surface of the block body in which the bolt is embedded to an opposite end surface and a thickness of the fastening member. It is characterized by being determined by the dimensions.

  According to the first aspect of the present invention, it is composed of two members, a block body made of concrete and a metal fastening member, and the resin member is excluded, so that a good affinity with concrete is maintained and the concrete is maintained. It is possible to prevent partial peeling.

At this time, the tightening member is for tightening the reinforcing bars and has little influence on the holding of the cover, so that the tightening member may be smaller than the block body. Therefore, although the fastening member is poor affinity with concrete as compared with the block body for a metal, since the ratio of the tightening member itself in the entire spacer is small, the concrete such as conventional resin member There is no risk of partial peeling.

Furthermore, by simply screwing the bolts embedded in the block body into the female thread part of the tightening member, the spacer can be fixed to the rebar by holding the rebar inside the tightening member together with the bolt. The spacer can be easily attached to the rebar without any need, and it is fixed by a combination of bolts and screws, so that the spacer can be displaced or removed even when vibration is applied by the vibrator when pouring concrete. Can be prevented.

Further, according to the invention described in claim 1, by reinforcing bars based on the inside position of the base that may contact, forming a female thread portion to the large consisting distance position from rebar diameter of one facing plate, fastening Since the rebar is sandwiched between the inner surface of the attachment member and the tip of the bolt, the bolt can be easily screwed into the female thread by screwing the block body, and the spacer can be easily attached to the rebar without skill. Therefore, the spacer can be attached efficiently.

According to the second aspect of the present invention, the length of the bolt is set so as to protrude to the inside of the tightening member by an amount corresponding to half or more of the diameter of the reinforcing bar when screwed with the female thread portion of the bolt. Therefore, even if the internal thread portion is formed at a position larger than the diameter of the reinforcing bar from the inner position of the base portion where the reinforcing bar can come into contact as in the invention described in claim 2, By screwing, the reinforcing bar can be firmly held between the inner side surface of the tightening member and the tip of the bolt, and the positional displacement and detachment of the spacer due to vibration of the vibrator or the like can be reliably prevented.

According to the invention described in claim 3 , since the other opposing piece of the fastening member is shorter than the one opposing piece on which the female thread portion for screwing the bolt is formed, the reinforcing bar is fitted inside the fastening member. When fitting the tightening member to the rebar, it is easy to fit the rebar inside the tightening member without hindering part of the tightening member while the bolt is shallowly screwed into the female thread part. Can do. Therefore, if the spacer is prepared in a state where the bolt is shallowly screwed and connected to the female thread portion, the spacer can be easily attached simply by fitting a reinforcing bar inside the fastening member and screwing the bolt as it is. It is possible to further improve the efficiency of the mounting work.

According to the invention described in claim 4 , when it is necessary to adjust to increase the cover allowance of concrete, it is easy to make the cover allowance of concrete by screwing a nut of a predetermined thickness onto the bolt. Can be adjusted.

According to the invention described in claim 5 , since the cover allowance can be basically adjusted by the length of the block body, the necessary cover allowance can be obtained by preparing a block body having a length corresponding to the cover allowance. It can be held securely.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS. However, FIGS. 1 and 2 are a perspective view and an exploded perspective view of the spacer, respectively, FIGS. 3 and 4 are cross-sectional views of the spacer in a used state from the lateral direction and from above, and FIGS. 5 and 6 are fastening members, respectively. It is the cutting | disconnection top view and back view of these.

  As shown in FIGS. 1 to 6, the reinforced concrete spacer 1 in the present embodiment is composed of two members, a concrete block body 3 and a metal U-shaped fastening member 5.

  The block body 3 has a substantially rectangular parallelepiped shape as a whole and has a curved outer shape at the tip, and is formed by pouring concrete into a mold and solidifying it. A bolt 7 is embedded in a flat end surface (end surface in the present invention) opposite to the curved surface of the block body 3 in a state where a part of the bolt 7 protrudes. It is embedded in concrete with a part protruding.

  The fastening member 5 is formed by bending a flat metal plate into a U-shape, and is formed at both ends of the base portion 5a and the base portions 5a facing each other with an interval of about 2 to 3 mm added to the diameter of the reinforcing bar. The opposing pieces 5b and 5c are formed, and one opposing piece 5b is formed with a female screw portion 9 into which the bolt 7 is screwed. The female screw portion 9 is formed such that the edge thereof is located at a distance smaller than the diameter of the reinforcing bar from the inner position (hereinafter referred to as a reference position) of the base portion 5a with which the reinforcing bar can come into contact. Strictly speaking, even if the center of the bolt 7 is located at a distance greater than the diameter of the reinforcing bar from the reference position, the bolt 7 screwed into the female screw portion 9 can contact the reinforcing bar in consideration of the diameter of the bolt 7. The formation position of the internal thread portion 9 is set so as to be in a state.

  In particular, as shown in FIG. 5, the protrusion amount L of the bolt 7 from the flat end surface of the block body 3 is the sum of the length L1 corresponding to half the diameter of the reinforcing bar and the thickness L2 of the fastening member 5. It is desirable to set it to be smaller than the value (= L1 + L2). If it carries out like this, at the time of screwing with the internal thread part 9 of the volt | bolt 7, it will protrude inside the clamping member 5 only by the part equivalent to the diameter of a reinforcing bar.

  When such a spacer 1 is actually used, the fastening member 5 is applied to a predetermined position of the reinforcing bar 11 so that the reinforcing bar 11 is fitted inside the fastening member 5 as shown in FIGS. . At this time, it is necessary to apply the tightening member 5 so that the facing piece 5b on which the female thread portion 9 is formed is positioned on the side where the covering margin should be held with respect to the reinforcing bar 11.

  Subsequently, when the bolt 7 of the block body 3 is screwed into the female screw portion 9 of the fastening member 5 and the bolt 7 is completely screwed into the female screw portion 9, the tip of the bolt 7 comes into contact with the reinforcing bar 11 and the fastening member 5. Reinforcing bar 11 is sandwiched between the inner surface and bolt 7, and spacer 1 is fixed to reinforcing bar 11. Here, as shown in FIG. 4, the total dimension of the length of the block body 3 and the thickness of the fastening member 5 (opposing piece 5b) is held as a concrete covering margin T.

  Furthermore, the concrete formwork 13 is arrange | positioned on the opposite side to the embedding surface of the volt | bolt 7 of the block body 1, the concrete 15 is poured in into the formwork 13, and a reinforced concrete structure is shape | molded. At this time, the concrete 15 is poured while applying vibration by the vibrator. However, since the reinforcing bar 11 is sandwiched between the inner surface of the fastening member 5 and the bolt 7, the positional displacement or detachment of the spacer 1 due to vibration may not occur. Absent.

  As described above, the distance between the opposing pieces 5b and 5c of the fastening member 5 is set to be slightly larger than the diameter of the reinforcing bar 11, but the diameter of the reinforcing bar 11 is not necessarily uniform and varies. Therefore, if the diameter is set to be the same as the diameter of the reinforcing bar 11, the reinforcing bar 11 may not be fitted inside the fastening member 5 when the fastening member 5 is applied to the reinforcing bar 11. Therefore, it is possible to easily cope with such a situation by providing some play in the interval between the opposing pieces 5b and 5c. Note that the play in this case is set to a value within an allowable range of the concrete cover allowance.

  On the other hand, by providing a slight play in the distance between the opposing pieces 5b and 5c, a gap is generated between one of the opposing pieces 5b and 5c and the reinforcing bar 11 when the fastening member 5 is applied to the reinforcing bar 11. However, by tightening the bolt 7, the base 5 a of the tightening member 5 is not parallel to the reinforcing bar 11 (see FIG. 4), and the tip of the bolt 7 is connected to the reinforcing bar 11 while maintaining a slightly inclined state. In this state, the spacer 1 is firmly fixed to the reinforcing bar 11.

  Therefore, according to 1st Embodiment, since the resin-made members like the past were excluded, good affinity with concrete can be maintained and partial peeling of concrete can be prevented beforehand.

  Further, since the bolt 7 can be easily screwed into the female thread portion 9 by screwing the block body 3 into the tightening member 5, the spacer 1 can be easily and firmly attached to the reinforcing bar 11 without requiring special skills as in the prior art. It is possible to reliably prevent the spacer 1 from being displaced or detached due to the vibration of the vibrator when the concrete is poured.

  Further, by preparing a plurality of types of block bodies 3 having different lengths according to the cover allowance, the bolt 7 of the block body 3 is completely screwed into the female threaded portion 9 so that the concrete cover allowance for the molded concrete is desired. The value can be held securely.

  By the way, in embodiment mentioned above, when the internal thread part 9 is formed so that the edge may be located in the distance larger than the diameter of a reinforcing bar from the inner side position (reference position) of the base 5a which can contact a reinforcing bar. As shown in FIG. 5, the protrusion amount L of the bolt 7 from the flat end surface of the block body 3 is a total value of the length L1 corresponding to half the diameter of the reinforcing bar and the thickness L2 of the fastening member 5 ( = L1 + L2) and preferably smaller than (L1 + 2 × L2).

  In this way, in order to make it easy to apply the tightening member 5 to the reinforcing bar 11, the base portion 5 a of the tightening member 5 can be obtained by tightening the bolt 7 even if some play is provided in the interval between the opposing pieces 5 b and 5 c. Is not parallel to the reinforcing bar 11 (see FIG. 4), and the bolt 7 is screwed into the female screw portion 9 while maintaining a slightly inclined state, and the reinforcing bar 11 is tightened strongly. Can be firmly fixed to the reinforcing bar 11.

(Second Embodiment)
A second embodiment of the present invention will be described with reference to FIGS. In the present embodiment, the difference from the first embodiment described above is that, as shown in FIGS. 7 and 8, the other opposing piece 5 c of the fastening member 5 is a female thread portion for screwing the bolt 7 of the fastening member 5. 9 is shorter than the one of the opposing pieces 5b on which the bolt 9 is formed, and is set to such a length that the rebar 11 can be contacted when the bolt 7 is screwed. The other configuration is basically the first embodiment. The form is the same.

  By doing so, the opening portion of the fastening member 5 is widened and the rebar 11 is easily fitted inside the fastening member 5. Therefore, as shown in FIG. If the spacer 1 is prepared in this state, the spacer 1 can be easily attached simply by fitting the reinforcing bar 11 inside the fastening member 5 and screwing the bolt 7 as it is.

  Therefore, according to the second embodiment, the effect equivalent to that of the first embodiment can be obtained, and the spacer 1 is mounted at a predetermined position of the reinforcing bar 11 and the bolt 7 is screwed as it is. The spacer 1 can be attached simply by moving, so that one-touch operation of so-called attachment work can be realized and work efficiency can be improved.

  Also in this embodiment, the protrusion amount L of the bolt 7 from the flat end surface of the block body 3 is the length L1 corresponding to half the diameter of the reinforcing bar shown in FIG. 5 and the thickness L2 of the fastening member 5. It is desirable to set so as to be larger than the total value (= L1 + L2) and smaller than (L1 + 2 × L2).

(Third embodiment)
A third embodiment of the present invention will be described with reference to FIGS. In the present embodiment, the difference from the first embodiment described above is that, as shown in FIGS. 9 and 10, the central base portion 5 a of the metal U-shaped fastening member 5 is opposite to the curved surface of the block body 3. Is fixed to the flat end surface (end surface in the present invention) by the connecting member 21, and the female thread portion 25 for screwing of the bolt 23 is formed on one of the opposing pieces 5b. The other configuration is basically the same as that of the first embodiment. The same.

  At this time, the connecting member 21 is made of a rod-like body with a flange-like head, such as a nail, and is formed on the base 5a of the fastening member 5 when the concrete is solidified in the mold to form the block body 3. The connecting member 21 is inserted in advance from the inside of the tightening member 5 into a through hole (not shown) that is provided, and the tightening member 5 is fixed to the end surface of the block body 3 by solidification of the concrete. Further, the position of the female screw portion 25 is a position that is a distance larger than the diameter of the reinforcing bar 11 with respect to the inner position of the base portion 5a with which the reinforcing bar 11 can come into contact, and by screwing the bolt 23 to the female screw portion 25. It is desirable that the inner surface of the fastening member 5 and the tip of the bolt 23 be formed at a position where the reinforcing bar 11 can be sandwiched.

  Then, as shown in FIG. 10, the fastening member 5 is placed at a predetermined position of the reinforcing bar 11 so that the reinforcing bar 11 is fitted inside the fastening member 5, that is, between the opposing pieces 5 b and 5 c of the fastening member 5. The bolt 23 is screwed into the female screw portion 25 of the tightening member 5. Here, when the bolt 23 is screwed into the female screw portion 25, the tip of the bolt 23 comes into contact with the reinforcing bar 11, and the reinforcing bar 11 is sandwiched between the inner surface of the fastening member 5 and the tip of the bolt 23, and the spacer 1 is It is fixed to the reinforcing bar 11. In addition, as shown in FIG. 4, the total dimension of the length of the block body 3 and the thickness of the fastening member 5 (base part 5a) is hold | maintained as the covering margin T of concrete.

  By the way, if the bolt 23 is integrated with the block body 3 and the fastening member 5 in a state where the bolt 23 is shallowly screwed into the female thread portion 25 so that the tip does not protrude inside the fastening member 5, the block body 3 is obtained. The attachment work to the reinforcing bar 11 can be performed efficiently.

  Therefore, according to the third embodiment, the same effect as that of the first embodiment can be obtained, and the base portion 5a at the center of the fastening member 5 is fixed to the block body 3. When the fastening member 5 is applied to the reinforcing bar 11 so that the reinforcing bar is fitted inside the fastening member 5, the reinforcing bar 11 is simply fitted between the opposing pieces 5b, 5c of the fastening member 5 and tightened. The member 5 can be applied to the reinforcing bar 11 and workability can be improved.

  In FIG. 10, the interval between the opposing pieces 5 b and 5 c of the fastening member 5 is shown to be slightly larger than the diameter of the reinforcing bar 11, but the interval between the opposing pieces 5 b and 5 c is larger than the diameter of the reinforcing bar 11. Even if the play of the bolt 23 is large, it is only necessary to set so that the reinforcing bar 11 can be clamped by the inner surface of the fastening member 5 and the tip of the bolt 23 when the bolt 23 is screwed into the female screw portion 25. . Here, if the play between the opposing pieces 5b, 5c of the tightening member 5 is large, the block body 3 can be attached to reinforcing bars of various diameters even with one kind of tightening member 5. Sex spreads.

  The present invention is not limited to the above-described embodiments, and various modifications other than those described above can be made without departing from the spirit of the present invention.

  For example, the shape of the block body 3 is not limited to the above, and may be a rectangular parallelepiped shape, a cubic shape, a hemispherical shape, or the like.

  Further, in the fastening member 5, the dimensions of the facing pieces 5b and 5c are not the same as described above, but may be different. Furthermore, the outer shape of the fastening member 5 is not limited to the U-shape described above, but may be a U-shape.

  Further, in the first embodiment described above, when it is necessary to adjust the covering margin T (see FIG. 4) in the direction of increasing, a nut having a predetermined thickness corresponding to the adjustment is prepared in advance and screwed to the bolt 7. Alternatively, it may be embedded in the block body 3 together with the bolts 7 in a screwed state.

It is a perspective view of the spacer for reinforced concrete in 1st Embodiment of this invention. It is a disassembled perspective view of the spacer for reinforced concrete in 1st Embodiment of this invention. It is sectional drawing which looked at the spacer for reinforced concrete in 1st Embodiment in use condition from the horizontal direction. It is sectional drawing which looked at the spacer for reinforced concrete in 1st Embodiment in use condition from upper direction. It is a cutting plan view of a part of the spacer for reinforced concrete in the first embodiment. It is a partial rear view of the spacer for reinforced concrete in 1st Embodiment. It is a disassembled perspective view of the spacer for reinforced concrete in 2nd Embodiment of this invention. It is a cutting top view of a part of the reinforced concrete spacer in the second embodiment. It is a perspective view of the spacer for reinforced concrete in 3rd Embodiment of this invention. It is sectional drawing which looked at the spacer for reinforced concrete in 3rd Embodiment in use condition from upper direction. It is a perspective view of a prior art example. It is a perspective view of another prior art example. It is a perspective view of a different conventional example. It is operation | movement explanatory drawing at the time of use of FIG. Furthermore, it is a perspective view in the use condition of a different conventional example. It is a cutting | disconnection side view in the use condition of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reinforced concrete spacer 3 Block body 5 Tightening member 5a Base part 5b, 5c Opposing piece 7,23 Bolt 9,25 Female thread part 11 Reinforcement 15 Concrete T Cover allowance

Claims (5)

In constructing a reinforced concrete structure, in a reinforced concrete spacer for maintaining the cover of concrete by maintaining a predetermined distance between the reinforcing bar and the formwork arranged outside thereof,
A concrete block body for securing the covering margin, a metal clamping member having a substantially U-shape or a substantially U-shape for fixing the block body to the reinforcing bar, and A bolt for holding the reinforcing bar inside,
The bolt is embedded in the block body,
The tightening member is formed with a female thread portion into which the bolt is screwed,
The fastening member is
Formed by bending or bending a metal plate,
A base portion and opposing pieces at both ends of the base portion facing each other with a gap slightly larger than the diameter of the reinforcing bar,
The female thread portion is
One of the opposing pieces, formed from a position that is larger than the diameter of the reinforcing bar, from the inner position of the base portion where the reinforcing bar can contact,
Spacer for reinforced concrete, wherein the block body is fixed to the reinforcing bar by holding the reinforcing bar between the inner surface of the tightening member and the tip of the bolt by screwing with the female screw part of the bolt. .   The bolt is embedded in one end surface of the block body, and has a length that protrudes to the inside of the fastening member by an amount corresponding to half or more of the diameter of the reinforcing bar when screwed with the female screw portion. The spacer for reinforced concrete according to claim 1, wherein the spacer is set. The other opposing piece of the tightening member is shorter than one opposing piece, and is set to a length capable of contacting the reinforcing bar when screwed with the female thread portion of the bolt. The spacer for reinforced concrete according to claim 1 or 2 . The reinforced concrete spacer according to any one of claims 1 to 3 , wherein a nut having a predetermined thickness is screwed onto the bolt. The head margin is at least the length to the end face of the opposite from the one end surface which is embedded the bolts of the block body, claims 1, characterized in that determined by the total size of the thickness of the fastening member 4 The spacer for reinforced concrete in any one of.

Images