JP2008308941A - Covering thickness checking tool, and covering thickness checking method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reinforcing bar covering thickness checking tool, and a covering thickness checking method for correctly checking thickness of covering of a reinforcing bar in a reinforced concrete structure prior to placement of concrete without limitation to the position of the subject reinforcing bar, and regardless of applications, which is excellent in portability. <P>SOLUTION: The tool comprises a measuring part B1 composed of a spherically shaped timber having a radius corresponding to the minimum value of covering thickness, with a recess bored in part of the surface of the measuring part B1, and a flat countersunk head screw driven to a bottom surface of the recess for composing a connection part B1a to a handle shaft part B2. The handle shaft part B2 is in such constitution as that of an extensible rod antenna or a telescopic rod. A magnet having a flat surface is installed on a tip, and a connection part B2a is formed to be connected to the measuring part B1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a cover thickness confirmation jig used for confirming a separation distance between a reinforcing bar and a formwork, and a cover thickness confirmation using the same, in order to ensure a desired cover thickness of the reinforcing bar in a reinforced concrete structure. It is about the method.

  Conventionally, in a reinforced concrete structure, the steel bar rusts due to the progress of neutralization of the concrete, leading to a decrease in strength. In order to suppress this strength reduction, it is necessary to secure a desired cover thickness for the reinforcing bars. In order to ensure the desired cover thickness, it is preferable that the separation dimension between the reinforcing bar and the inner surface of the formwork is made to correspond to the desired cover thickness before placing the concrete, and the technique for confirming or ensuring the separation dimension There are various disclosures.

  For a reinforcing bar at the lower end of a slab or beam, a method of inserting a spacer having a dimension corresponding to a desired cover thickness into the reinforcing bar (see Patent Document 1) or supporting the reinforcing bar with a spacer is often employed. . These spacers are effective in that a desired cover thickness is surely ensured in a portion that is difficult to confirm after completion of bar arrangement or formwork assembly work.

  However, for example, at the wall surface of the finish finish or the rising part of the cloth foundation, the end of the spacer on the formwork side reaches the concrete surface and remains unexposed, and it is difficult to see, or in the structure of reinforced concrete. It is difficult to use repeatedly because it is buried in the wall, and there are problems that it is necessary to prepare multiple types according to the cover thickness depending on the part and it is costly, so it is common to refrain from using spacers .

  For these parts, the most common method is to insert a metal tape measure from the opening of the mold and apply the tape measure to the inner surface of the mold and the reinforcing bar after the rebar placement and the assembly of the mold are completed. Is. However, in this method, there is a possibility that an error may occur in the measurement result depending on how the tape measure is applied and the position of the measurer's viewpoint. In addition, it is difficult to measure at a site where rebars are crowded and the operator's hand and tape measure cannot be inserted.

  A rebar cover thickness measuring ruler for solving this problem is disclosed in Patent Document 2.

  According to the ruler of Patent Document 2, the ruler is inserted into the inner surface of the mold so as to be perpendicular to the inner surface of the mold, and the scale of the contact position of the reinforcing bar is read when the ruler comes into contact with the reinforcing bar. The distance between the inner surface and the reinforcing bar can be measured, and the cover thickness can be measured accurately regardless of the position of the viewpoint of the measurer. Moreover, it is supposed that it can measure easily also in the site | part where the reinforcing bar is crowded by inserting along the mold-frame inner surface vicinity without a reinforcing bar.

Japanese Patent Laid-Open No. 11-280207 Utility Model Registration No. 3078169

  However, since the ruler of Patent Document 2 has a narrow tip and gradually widens, for example, when a plurality of reinforcing bars to be measured are arranged in the insertion direction, only the closest reinforcing bar is measured. There was a problem that I could not.

  Further, even with this ruler, there is a problem in that it cannot be measured accurately unless it is at right angles to the inner surface of the mold and the axial direction of the reinforcing bar, and cannot be accurately measured if the usage method is wrong.

  Furthermore, when moving in the direction perpendicular to the insertion direction along the inner surface of the formwork, the ribs of the reinforcing bars (deformed reinforcing bars) and the ruler interfere with each other and cannot move smoothly. To change the measurement position, move the ruler once to the reinforcing bar. There is also a problem in that it is not easy to use because it must be inserted back to the position where it does not interfere.

  The present invention solves these problems of the prior art, and provides a rebar cover thickness confirmation jig that can be confirmed accurately regardless of the method of use without restriction on the position of the target rebar. It is intended to do.

  A first aspect of the present invention for solving the above-described problem is a cover thickness confirmation jig for confirming the cover thickness of a reinforcing bar before placing the concrete in a reinforced concrete structure. It is characterized by comprising a spherical or cylindrical measuring part having a diameter corresponding to the reinforcing bar cover thickness dimension, and a handle shaft part extending from the measuring part.

  The second configuration of the cover thickness confirmation jig according to the present invention is characterized in that, in addition to the first configuration, the measurement portion and the handle shaft portion have a detachable connecting portion.

  A third configuration of the cover thickness confirmation jig according to the present invention is characterized in that, in the second configuration, the detachable coupling mechanism uses a magnetic force.

  A fourth configuration of the cover thickness confirmation jig according to the present invention is characterized in that, in addition to the first to third configurations, the handle shaft portion has an expansion / contraction mechanism.

  The fifth configuration of the cover thickness checking jig according to the present invention is characterized in that, in addition to the first to third configurations, the handle shaft portion has flexibility.

  The second aspect of the present invention is a cover thickness confirmation method for confirming the cover thickness of a reinforcing bar before placing concrete in a reinforced concrete structure, wherein the measurement part of the cover thickness confirmation jig of the present invention is inserted and the measurement is performed. The cover thickness is confirmed by passing the part.

  According to the first configuration of the cover thickness confirmation jig according to the present invention and the cover thickness confirmation method according to the present invention, since the measurement unit is spherical or cylindrical having a diameter corresponding to a desired cover thickness, The position of the reinforcing bar is not limited to the closest reinforcing bar.

  Also, simply insert the measuring part into the gap between the inner surface of the formwork and the reinforcing bar without paying special attention to the direction, etc., and check whether the measuring part moves inside the formwork without interfering with the reinforcing bar. Thus, it is possible to easily confirm whether or not a desired separation dimension between the inner surface of the mold and the reinforcing bar, that is, the cover thickness is secured.

  Further, the movement inside the mold is smooth, and even when it interferes with the deformed reinforcing bar, it does not become difficult to move by meshing with the rib of the deformed reinforcing bar.

  According to the second configuration of the cover thickness confirmation jig according to the present invention, since the measuring part and the handle shaft part have the detachable connecting part, the storage property and the portability are further improved, and a plurality of different diameters are provided. The versatility can be enhanced by preparing a plurality of handle shaft portions having different measuring lengths and lengths.

  According to the third configuration of the cover thickness check jig according to the present invention, since the detachable connection between the measuring portion and the handle shaft portion uses magnetic force, the attaching / detaching operation can be easily performed instantly. Workability is further improved.

  According to the fourth configuration of the cover thickness confirmation jig according to the present invention, since the handle shaft portion has the expansion and contraction mechanism, it can be expanded or contracted according to the position of the target reinforcing bar, and can be contracted when not in use. Excellent workability, storage, and portability.

  According to the fifth configuration of the cover thickness confirmation jig according to the present invention, since the handle shaft portion is flexible, even if the jig cannot be linearly inserted, the handle shaft portion is bent and inserted. And the range of use of the jig can be expanded.

  A most preferred embodiment of a cover thickness confirmation jig and a cover thickness confirmation method according to the present invention will be described. An object of the present invention is to easily and accurately confirm whether or not the cover thickness of a reinforcing bar is appropriate before placing the concrete in the construction of the reinforced concrete structure.

  The cover thickness confirmation jig is composed of a measurement part and a handle shaft part.

  The measurement part is a part for confirming whether the distance from the reinforcing bar on the inner surface of the mold is secured to a desired cover thickness or more.

  The shape of the measurement part is spherical or cylindrical with a diameter corresponding to the cover thickness. Move the circle within the gap between the formwork and the reinforcing bar with one end of the circle having a diameter corresponding to the desired cover thickness of the reinforcing bar in contact with the inner surface of the formwork at right angles. It is possible to confirm whether or not a desired cover thickness is ensured by checking whether the other edge of the steel bar interferes with the reinforcing bar by visual observation or resistance acting on the hand.

  When the measuring part is spherical, there is no directionality and it can be confirmed from any direction and at any angle, and when it is cylindrical, the side made of a curved surface is brought into contact with the inner surface of the mold It can be confirmed by inserting it in the gap and moving it in a direction substantially perpendicular to the axial direction.

  The material of the measuring part is preferably light weight that does not deform even when subjected to compressive force by interfering with reinforcing bars or molds.For example, a material obtained by processing wood into a spherical or cylindrical shape or a hard synthetic resin such as spherical or What was shape | molded in the cylindrical shape is preferable.

  In addition, the minimum value of the cover thickness of the reinforcing bar is stipulated in the Building Standard Law. For example, in the case of a foundation, the rising portion is 4 cm and the other portion in contact with the soil is 6 cm. Since the minimum value of the cover thickness stipulated in the Building Standards Act is not broadly set in detail, even if a measuring part having a diameter corresponding to the specified value of the cover thickness is prepared, it does not become so many varieties.

  The handle shaft part is a part for operating the measurement part inside the mold.

  It is essential that the handle shaft part is thinner than the measurement part, i.e., does not have a thickness exceeding the desired cover thickness dimension, and depending on the insertion direction and the position of the target reinforcing bar as it gets thicker, Since it becomes easy to interfere, it is preferable that it is as thin as possible in the range which does not impair toughness.

  Further, for example, it is preferable to have a telescopic mechanism such as a telescopic rod antenna or a pointing rod because it is convenient for carrying and can be adjusted in length depending on the position of the reinforcing bar.

  Also, for example, when measuring a rebar that becomes a shadow of an obstacle or a part that cannot be inserted linearly because the formwork is bent or curved when it is made of a flexible material such as the tip of a fishing rod Can be supported.

  The measurement part and the handle shaft part may be connected in a fixed manner that cannot be attached or detached, or may be provided with a detachable connection mechanism. When it is possible to attach and detach, it is preferable that a plurality of types of measuring parts and handle shaft parts are prepared and this combination is changed so that many variations can be constructed with a small number of parts.

  As a detachable coupling mechanism, in addition to using a magnetic force, the handle shaft tip may be bolted and a through hole may be formed in the measurement part and fixed with a nut, or a female screw may be formed in the measurement part and screwed together. Good. In particular, the use of magnetic force is preferable because it can be easily attached and detached instantly. Also, in the case of magnetic force, in order to suppress dropout when force is applied from the lateral direction (perpendicular to the axial direction of the handle shaft), it corresponds to the shape of the connecting portion on the handle shaft side to the connecting portion on the measuring unit side. It is preferable that a recessed portion is provided, and the clearance between the connecting portion on the measurement portion side and the connecting portion on the handle shaft portion side is reduced and fitted.

  Next, an embodiment of the cover thickness confirmation jig and the cover thickness confirmation method using the jig according to the present invention will be specifically described with reference to the drawings. FIG. 1 is an example of a reinforced concrete structure to which the reinforcing bar cover thickness checking jig and the cover thickness checking method according to the present invention can be applied, and FIG. 1A is an inverted T-shaped cross section having a rising part and a base part. FIG. 1B is a diagram showing a completed state of the fabric foundation A. FIG. FIG. 2 is a diagram showing a configuration of a cover thickness confirmation jig according to the present embodiment, FIG. 3 is a diagram showing an embodiment of a cover thickness confirmation method at the rising portion of the fabric foundation, and FIG. 4 is a cover thickness at the base portion of the fabric foundation. The figure which shows the Example of a confirmation method, FIG. 5: is a figure which shows the structure of the other Example of the measurement part of a cover thickness confirmation jig | tool.

  In FIG. 1, the reinforcing bar is composed of a rising part reinforcing bar A11 and a base part reinforcing bar A12. The rising portion reinforcing bar A11 is configured by welding a main reinforcing rod A11a arranged horizontally near the upper and lower ends of the rising portion and a stirrup A11b arranged at a predetermined pitch in the vertical direction. The base rebar A12 is configured by welding a main reinforcing bar A12a arranged at a predetermined pitch in a direction orthogonal to the length direction of the fabric foundation A and an auxiliary reinforcing bar A12b connecting both ends of the main reinforcing bar A12a. A pair of rising part molds A21 and base part molds A22 are arranged at positions corresponding to the side surfaces of the rising part and the base part. In addition, in order to provide a ventilation port for ventilating under the floor (a notch portion of the upper end of the foundation) at a predetermined position at the upper end of the rising portion, a ventilation port mold A23 corresponding to the shape of the ventilation port is arranged.

  In FIG. 2, the measurement part B1 is made of a timber processed into a spherical shape having a radius corresponding to the minimum value of the cover thickness, and a recess is formed by partially passing through the surface of the measurement part B1, and a countersunk screw is formed on the bottom surface of the recess. Is connected to form the connecting portion B1a with the handle shaft portion B2. The handle shaft part B2 has the same configuration as a telescopic rod antenna or insertion rod, and a connecting part B2a connected to the measuring part B1 is formed by attaching a magnet having a flat surface to the tip. In addition, the handle shaft portion B2 is flexible and is configured to bend when a force is applied in a direction perpendicular to the axial direction, and to return to a linear state when the force is released. . The shape of the connecting portion B1a of the measuring portion B1 corresponds to the shape of the connecting portion B2a of the handle shaft portion B2, and is measured even when a force is applied from the lateral direction (a direction perpendicular to the axial direction of the handle shaft portion 2B). The part B1 is configured not to easily fall off.

The procedure for checking the cover thickness of the reinforcing bar A21 at the rising portion (the cover thickness in the width direction of the foundation A) is as follows.
(1) Connect the connecting parts B1a and B2a, attach the measuring part B1, and extend the handle shaft part B2 to an appropriate length (see FIG. 2).
(2) The measuring part B1 is inserted from the upper open part in a state where the setting of the mold A21 at the rising part is completed, and the measuring part B1 is moved to the position of the rising part reinforcing bar A12 along the inner surface of the mold A21. . In addition, as long as the handle shaft part B2 does not interfere with the formwork A21 or other foundation reinforcing bars not subject to the cover thickness check, the handle shaft part B2 may be inserted so as to be inclined with respect to the inner surface of the formwork A21 ( (See FIG. 3).
(3) The measurement unit B1 is appropriately moved in the vicinity of the reinforcing bar A11 that is the object of the cover thickness confirmation, and the measurement unit B1 is smooth without interfering with the reinforcing bar A11 in the gap between the reinforcing bar A11 and the inner surface of the mold A21. It is possible to confirm whether or not the cover thickness is ensured by whether or not the passage is blocked due to interference with the reinforcing bar A11 (see FIG. 3).

  The cover thickness of the reinforcing bar A12 in the base portion (the cover thickness in the width direction of the foundation A) also rises after mounting the measuring unit B1 having a diameter corresponding to the minimum value of the cover thickness required for the reinforcing bar A12 of the base portion. Similarly to the part, it is possible to check whether or not the cover thickness is ensured by inserting the measuring part B1 into the gap between the reinforcing bar A21 and the inner surface of the mold A22 (see FIG. 3).

  Further, even in a portion that is difficult to visually confirm, such as between the corner portion of the vent opening formwork A23 shown in FIG. The measuring part B1 is inserted while bending 2 and the cover thickness can be confirmed by whether or not the measuring part B1 interferes with the ventilator formwork A23. Further, since the handle shaft portion B2 is flexible, even if it is a portion where it is difficult to insert the cover thickness check jig B, such as between the main muscle A11a and the bottom portion of the vent form A23. The cover thickness can be confirmed by inserting the portion B2 while pressing and bending the portion B2 against the main muscle A11a.

  Next, another embodiment of the measurement unit of the cover thickness confirmation jig and a cover thickness confirmation method using the same will be described. As shown in FIG. 5, in this embodiment, the measuring part B1 is cylindrical. The connecting part B1a of the measuring part B1 is formed at two places, that is, a side surface composed of a small face and a curved surface. When the connecting part B2a of the handle shaft part B2 is connected to the connecting part B1a1 of the small face, the measuring part B1 The axial direction coincides with the axial direction of the handle shaft portion B2, and is configured to be orthogonal to the axial direction of the measuring portion B1 and the axial direction of the handle shaft portion B2 when connected to the side connecting portion B2a.

  By comprising in this way, the position of a connection can be suitably changed and used according to the arrangement direction of reinforcement A1 used as the direction in which handle axis part B2 can be inserted and moved, and cover thickness confirmation. For example, when confirming the cover thickness of the plurality of main bars A11a arranged at the rising portion of the fabric foundation A, the cover thickness check jig uses the connecting portion B1a1 on the small edge surface and the axial direction of the measurement unit B1 is substantially vertical. By moving B in the substantially horizontal direction (the length direction of the fabric foundation A) along the main muscle A11a, it is possible to confirm accurately while continuously allowing the measurement unit B1 to swing up and down. In addition, when a portion where the cover thickness is not ensured during movement in the substantially horizontal direction appears, the side surface of the measurement unit B1 configured with a curved surface comes into contact with the surface of the reinforcing bar A11a, and thus acts on the measurement unit B1. The impact to be performed is small, and the measurement part B1 is difficult to drop off.

  Further, when the cover thickness check jig B cannot be moved in the horizontal direction due to an obstacle such as the width stopper of the mold A21 or the ventilator mold A23, the side connecting part B1a2 is used to connect the axis of the measuring part B1. They can be connected so that their directions are substantially horizontal. By doing in this way, if the state where the side surface of the measurement part B1 is in linear contact with the inner surface of the mold A21 is maintained, the length of the measurement part B1 is not required to keep the handle shaft part B2 vertical. It is possible to accurately check the cover thickness of the steel bars.

  The cover thickness confirmation jig according to the present invention is used for confirming the distance between the reinforcing bar and the formwork in the reinforced concrete structure, but is also used for confirming the interval between the reinforcing bars after the bar arrangement is completed. it can.

It is a figure which shows an example of the reinforced concrete structure to which the covering thickness confirmation jig | tool and covering thickness confirmation method of a reinforcing bar concerning this invention are applicable. It is a figure which shows the structure of the Example of a cover thickness confirmation jig | tool. It is a figure which shows the Example of the confirmation method of the cover thickness in a standing part. It is a figure which shows an Example about the confirmation method of the cover thickness in a base part. It is a figure which shows the structure of the other Example of the measurement part of a cover thickness confirmation jig | tool.

Explanation of symbols

A Cloth foundation (steel reinforced concrete structure)
A11 Standing part reinforcing bar A11a Main bar A11b Stirrup A12 Base part reinforcing bar A12a Main bar A12b Auxiliary reinforcement A13 Reinforcing bar A21 Standing part formwork A22 Base part formwork A23 Ventilation vent formwork B Cover thickness check jig B1 Measuring part B1a Connection part B1a1 Small facet connection part B1a2 Side connection part B2 Handle shaft part B2a Connection part

Claims (6)

A cover thickness confirmation jig for confirming the cover thickness of a reinforcing bar before placing concrete in a reinforced concrete structure,
A spherical or cylindrical measuring section having a diameter corresponding to the desired rebar cover thickness dimension;
A cover thickness confirmation jig comprising: a handle shaft portion extending from the measurement portion.   The cover thickness confirmation jig according to claim 1, wherein the measurement part and the handle shaft part have a detachable connecting part.   The cover thickness confirmation jig according to claim 2, wherein the detachable connecting portion uses magnetic force.   The cover thickness confirmation jig according to any one of claims 1 to 3, wherein the handle shaft portion has an expansion / contraction mechanism.   The cover thickness confirmation jig according to claim 1, wherein the handle shaft portion has flexibility. A cover thickness confirmation method for confirming the cover thickness of a rebar before placing concrete in a reinforced concrete structure,
The measuring part of the covering thickness check jig according to any one of claims 1 to 5 is inserted between the reinforcing bar to be checked for covering thickness and the inner surface of the mold, and the covering part passes through the measuring part. A cover thickness confirmation method characterized by confirming the thickness.

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