JP6371196B2 - Anchor construction jig and anchor construction unit - Google Patents

Description

  The present invention relates to an anchor construction jig and an anchor construction unit.

  Conventionally, an expansion anchor is frequently used as an anchor used for fixing an attachment (including a panel, a sheet, and the like) to a base material such as a concrete frame, and for interlaminar bonding of a base material composed of a plurality of layers. The expansion anchor is inserted into a pilot hole drilled in a base material such as a concrete frame, and is fixed to the base material by expanding a tip portion (expansion portion). As such an expansion anchor, a sleeve driving type expansion anchor or the like is known (for example, see Patent Document 1).

JP-A-56-46111

  However, in the above-described sleeve driving type expansion anchor, the operator used hammer response and hammering sound as a guideline for completion of construction. Therefore, depending on the skill difference of the workers, for example, it is determined that the construction has been completed although the construction has not been completed normally, and there is a concern that the construction reliability may be reduced.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide an anchor construction jig and an anchor construction unit that enable highly reliable anchor construction.

  According to one aspect of the present invention, a cylindrical sleeve having a through hole and an extended portion, and an anchor bolt that expands the extended portion by driving the sleeve are used for the construction of an expanded anchor. A jig for anchor construction, which is formed in the main body portion for applying a driving force during construction to the sleeve, and the expansion anchor is constructed by facing a part of the anchor bolt inside. An anchor construction jig is provided that includes an opening window that allows completion confirmation.

  In the first aspect described above, a configuration may be provided that further includes a driving amount suggesting portion that is provided at an opening end of the opening window and suggests a driving amount of the sleeve.

  In the first aspect, a configuration in which a plurality of driving amount suggesting portions are provided may be employed.

  In the first aspect, the driving amount suggesting portion may be configured based on a position of a bolt tip of the anchor bolt that has been installed by a predetermined amount of the sleeve.

  In the first aspect described above, the construction may further include a marking portion that can mark the anchor bolt when the construction of the expansion anchor is completed.

  In the first aspect, the marking portion may be detachable from the main body portion.

  In the first aspect, the marking portion may be configured to give the marking to a bolt tip of the anchor bolt.

  According to two aspects of the present invention, a cylindrical sleeve having a through hole and an extended portion, an anchor bolt including a bolt portion and a head, and extending the extended portion by the head by driving the sleeve There is provided an anchor construction unit having an expansion anchor including the anchor and the anchor construction jig according to any one of claims 1 to 7.

  In the second aspect, the anchor bolt may have a construction completion suggesting portion that suggests a state in which construction has been completed by driving the sleeve by a predetermined amount.

  In the second aspect, the bolt portion may have a configuration in which predetermined information regarding the anchor bolt is stamped at a tip.

  In the second aspect, the anchor bolt may include a convex member provided at a tip of the head and having an outer diameter smaller than that of the head.

  In the said 2nd aspect, the said convex member is good also as a structure which can be attached or detached with respect to the said head.

  According to the present invention, it is possible to visually confirm the completion of the construction of the expansion anchor through the opening window. Therefore, since the completion of anchor construction can be easily and reliably determined regardless of the skill difference between workers, the occurrence of poor construction is suppressed, and as a result, highly reliable anchor construction can be achieved.

It is a figure which shows schematic structure of the anchor construction unit of this embodiment. It is a figure which shows schematic structure of the anchor of this embodiment. It is a figure which shows schematic structure of the jig | tool of this embodiment. It is a figure which shows the fixing process to the base material of the attachment by an anchor construction unit. It is a figure for demonstrating the function by the expansion part of the anchor of this embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
An anchor construction jig according to an embodiment of the present invention and an anchor construction unit including the jig will be described with reference to the drawings. The anchor construction jig of the present embodiment is used for construction of a sleeve driving type anchor (hereinafter simply referred to as an anchor). The anchor construction unit of the present embodiment is a unit obtained by unitizing the anchor and the anchor construction jig of the present invention (hereinafter simply referred to as a jig).

  FIG. 1 is a diagram showing a schematic configuration of an anchor construction unit of the present embodiment. FIG. 2 is a diagram showing a schematic configuration of the anchor of the present embodiment. FIG. 3 is a diagram illustrating a schematic configuration of the jig according to the present embodiment.

  As shown in FIG. 1, the anchor construction unit 1 of this embodiment includes an anchor 100 and a jig 110 used for construction of the anchor 100.

As shown in FIGS. 1 and 2, the anchor 100 includes a sleeve 10 and an anchor bolt 20.
A through hole 11 having a circular cross section is formed in the sleeve 10 from the rear end 10a to the front end 10b. An anchor bolt 20 is inserted in the through hole 11 in a state where it can be easily removed.

  The sleeve 10 has a confirmation marker 24 formed on the surface in the vicinity of the rear end 10a. The confirmation marker 24 is used as an index for determining whether or not the drilling depth of the pilot hole in which the anchor 100 is to be constructed is correct. The drilling depth of the pilot hole is appropriately set according to the anchor 100 to be constructed.

  In the sleeve 10, a plurality of slits 13 are formed along the length direction from the distal end 10 b toward the rear end in the distal end portion 12 that is a portion including the distal end 10 b. The sleeve 10 is divided into a plurality of projecting piece-like extended portions 14 by a plurality of slits 13. In the present embodiment, for example, four slits 13 are formed at intervals of 90 ° in the circumferential direction. As a result, the sleeve 10 has the distal end portion 12 divided into four expansion portions 14.

  The expansion part 14 can be deformed radially outward (expansion direction) when pressed outward by the anchor bolt 20. The extended portion 14 has an inner surface 14a that is tapered so that the thickness decreases from the rear end 10a toward the front end 10b.

  The anchor bolt 20 includes a bolt part 21, a head part 22, and a construction confirmation marker (construction completion suggestion part) 26. The bolt portion 21 has a male screw formed on the outer surface. The construction confirmation marker 26 is formed on the surface of the bolt part 21. In a state where the sleeve 10 is not driven, the construction confirmation marker 26 is hidden in the through hole 11 of the sleeve 10 (see FIG. 2). The construction confirmation marker 26 suggests a state in which the construction of the anchor 100 is completed by driving the sleeve 10 by a predetermined amount. The construction confirmation marker 26 is composed of, for example, colored ink, marking lines formed by printing or grooving.

  The head portion 22 is connected to the base portion 21b of the bolt portion 21, and has a tapered surface 22a that narrows the outer diameter toward the base portion 21b, a side surface 22b that extends downward from the tapered surface 22a, and a lower side of the side surface 22b. And a lower surface 22c.

  In the present embodiment, the head 22 is provided with a convex member 23 on the lower surface 22c. The convex member 23 is a cylindrical member that is smaller than the outer diameter of the head portion 22 (side surface 22b). The central axis of the convex member 23 coincides with the central axis of the head 22. Therefore, the outer diameters of the convex member 23 and the head 22 are concentric when viewed in plan.

In the present embodiment, the convex member 23 is formed integrally with the head portion 22.
The convex member 23 may be formed separately from the head 22, and in this case, the convex member 23 may be detachable from the head 22. Thus, if the convex member 23 is detachable, the convex member 23 having an appropriate outer diameter or height can be used according to the condition of the base material for constructing the anchor 100 (material and inner diameter of the construction hole). .

  Moreover, when the convex member 23 is detachable, the convex member 23 may be formed of the same metal as the constituent material of the anchor bolt 20, or different from the metal that is the main material constituting the anchor bolt 20. It may be formed of a resin material.

  In the sleeve driving type anchor 100 as in this embodiment, when the sleeve 10 is driven into a prepared hole (construction hole), the head portion 22 of the anchor bolt 20 enters the distal end portion 12. The expansion part 14 is deformed radially outward (expansion direction) by being pressed outward by the head 22 of the anchor bolt 20. Thereby, the expansion part 14 is pushed and expanded inside the construction hole, so that the anchor 100 is fixed in a wedge shape on the inner wall surface of the lower hole formed in the base material and is held well.

  As shown in FIGS. 1 and 3, the jig 110 includes a main body portion 30, an opening window 31 formed in the main body portion 30, a construction completion line (insertion amount suggestion portion) 32, and a marking portion 33. ing. The jig 110 is attached to a hammer drill used when constructing the anchor 100. The jig 110 is a jig for transmitting a striking force (driving force) from the hammer drill to the sleeve 10.

  The main body 30 is composed of a metallic cylindrical member. The main body part 30 can insert the anchor bolt 20 (bolt part 21) of the anchor 100 to be constructed into the inside from one end 30a side. One end 30a of the main body portion 30 has substantially the same outer diameter as that of the sleeve 10, and comes into contact with the sleeve 10 when the bolt portion 21 is inserted therein. Thus, the main body 30 efficiently transmits the striking force from the hammer drill to the sleeve 10.

  The opening window 31 exposes a part of the bolt part 21 inserted into the main body part 30. Here, when the sleeve 10 is driven, the relative positions of the sleeve 10 and the anchor bolt 20 change. That is, as the sleeve 10 is driven by the jig 110, the position of the tip 21a of the bolt part 21 exposed in the opening window 31 changes.

  In the present embodiment, a construction completion line (driving amount suggestion portion) 32 serving as an index indicating the driving amount of the sleeve 10 with respect to the anchor bolt 20 is provided. The construction completion line 32 is composed of, for example, colored ink, marking lines formed by printing or grooving at the opening edge of the opening window 31.

  The construction completion line 32 is set based on the position of the tip 21a of the bolt part 21 of the anchor bolt 20 that has been constructed by driving the sleeve 10 by a predetermined amount. That is, the state in which the tip 21a of the bolt portion 21 exposed in the opening window 31 coincides with the construction completion line 32 means a state in which the driving of the sleeve 10 is completed.

  In the present embodiment, the construction completion line 32 includes, for example, a plurality of marking lines 32a, 32b, and 32c. Each marking line 32a, 32b, 32c is set according to the length of the anchor bolt 20 of the anchor 100 to be constructed. That is, since each marking line 32a, 32b, and 32c can be used as an index, the jig 110 of this embodiment can be used for three types of anchors 100. The plurality of marking lines 32a, 32b, and 32c have different colors, for example. According to this, the marking lines 32a, 32b, and 32c can be easily discriminated by the difference in color, and the judgment at the completion of the construction can be easily and surely performed without mistake. Note that the number of marking lines in the construction completion line 32 is not limited to three, but may be four or more, or may be composed of only one marking line. Further, the marking lines 32a, 32b, and 32c may all be the same color. Moreover, the thickness of each marking line 32a, 32b, 32c may differ, respectively, and all may be the same thickness.

  The marking part 33 marks the tip 21a of the anchor bolt 20 when the construction of the anchor 100 is completed.

  The marking part 33 can contact the tip 21a of the bolt part 21 reaching the construction completion line 32 (for example, the marking line 32b). If the tip 21a of the bolt part 21 does not reach the construction completion line 32 (that is, if the driving of the sleeve 10 is not completed), the tip 21a is not marked. The marking part 33 applies a predetermined urging force to the tip 21a of the bolt part 21 by a spring member or the like. Thereby, the marking part 33 can perform marking favorably, without giving an excessive load to the front-end | tip 21a.

  As information which the marking part 33 provides, the embedded length of the constructed anchor bolt 20 and the kind of anchor (a metal anchor or an adhesive anchor) can be illustrated, for example. Further, the marking method by the marking unit 33 is not particularly limited, and for example, a method of stamping predetermined character information by stamping or a stamping method using ink or the like can be employed. In addition, as the anchor bolt 20, it is assumed that the information regarding the type of the anchor (metal anchor or adhesive anchor) is stamped on the tip 21a from the beginning. In this case, the marking part 33 should just mark information on the front-end | tip 21a so that it may not overlap with the marking part from the beginning.

  In the present embodiment, the marking part 33 is detachable from the main body part 30. The main body part 30 may be provided with an opening / closing part (not shown) for making the marking part 33 detachable.

  Based on such a configuration, in the present embodiment, it is possible to give various information to the anchor bolt 20 by exchanging the marking portion 33. Therefore, if the tip 21a of the anchor bolt 20 after the completion of construction is visually observed, the construction conditions of the anchor 100 can be easily grasped even by a third party, so that construction management can be easily performed.

(Construction method)
Next, a construction method for fixing the attachment 70 to the base material 60 using the anchor construction unit 1 will be described with reference to FIG.
An attachment 70 that is an object to be fixed by the anchor 100 is an attachment fitting such as an angle or a saddle. Equipment such as various machines and devices can be fixed to the base material 60 via an attachment 70. Moreover, an instrument can also be directly fixed to the base material 60 via the anchor 100, and in this case, the attachment 70 is an instrument.

(Punching process)
As shown in FIG. 4A, a pilot hole (anchor construction hole) 61 is drilled in the base material 60 by a drill member 40 connected to a rotary tool (not shown). In this embodiment, a stopper 41 is attached to the drill member 40. The stopper 41 suppresses drilling by the drill member 40 when the drilling reaches a predetermined depth. Thereby, the predetermined drilling depth by the drill member 40 is securable.

In the present embodiment, for example, a dust suction drill is used as the drill member 40. The drill member 40 has a through hole (not shown) extending from the tip to the base, and forms a lower hole 61 while discharging chips generated during drilling by a dust absorber (not shown) connected to the base. To do.
Therefore, for example, after the drill member 40 is prevented from being scattered during the upward construction or the drill member 40 is pulled out from the lower hole 61, the chip remains in the hole bottom of the lower hole 61, and the embedding length is insufficient, or insufficient driving occurs. The occurrence of such troubles is prevented.

The drill member 40 may be an ordinary drill that does not have a dust absorbing function, or may be used in combination with the stopper 41. When a normal drill is used, a suction step or the like may be inserted into the lower hole 61 to provide a cleaning process for cleaning the inside.
Further, instead of the stopper 41, a line indicating the drilling depth may be formed on the drill. For example, the line may be formed with colored ink, or may be formed by groove processing.

(Insertion process)
As shown in FIG. 4B, the head portion 22 of the anchor bolt 20 and the expanded portion 14 of the sleeve 10, which are the distal end side of the anchor 100, are inserted into the prepared hole 61. At this time, it is confirmed whether or not the confirmation marker 24 formed on the sleeve 10 is hidden in the lower hole 61.

  Here, when the confirmation marker 24 is hidden in the pilot hole 61, the drilling depth of the pilot hole 61 by the above drilling process is sufficient, and the anchor 100 (anchor bolt 20 and sleeve 10) is surely reached to the hole bottom. Means that it has been inserted.

  On the other hand, when the confirmation marker 24 is not hidden in the lower hole 61 and can be visually confirmed, it means that the drilling depth of the lower hole 61 is insufficient. In this case, it is necessary to perform a cleaning process to remove chips remaining on the hole bottom, or to repeat the drilling process so that a sufficient drilling depth can be obtained.

  In the present embodiment, when the anchor bolt 20 is inserted into the lower hole 61, the convex member 23 comes into contact with the bottom of the lower hole 61. Here, the bottom of the prepared hole 61 drilled with a drill has a substantially conical shape. According to the present embodiment, the columnar convex member 23 is in contact with the bottom of the conical bottom of the lower hole 61, so that the anchor bolt 20 and the sleeve 10 are well placed at the center of the lower hole 61.

(Punching process)
Subsequently, as shown in FIG. 4C, the jig 110 is attached to a hammer drill (not shown), and a striking force is applied to the sleeve 10 through the jig 110. As a result, the sleeve 10 is driven into the lower hole 61. When the sleeve 10 is driven and moved downward, the head 22 of the anchor bolt 20 whose position is regulated by the lower hole 61 expands by pressing the expansion portion 14 outward (see FIG. 2).

In the present embodiment, since the anchor bolt 20 is in contact with the bottom of the lower hole 61 as described above, the reaction force at the time of driving is sufficiently transmitted to the expansion portion 14 side to facilitate the expansion portion 14. Extend to In addition, since the center of the anchor bolt 20 and the sleeve 10 coincides with the center of the lower hole 61 by the convex member 23, the four expansion portions 14 can be expanded evenly.
Therefore, according to the present embodiment, the expansion portion 14 is locked to the inner surface 61a of the lower hole 61 by functioning stably. Therefore, high construction reliability can be obtained.

  FIGS. 5A and 5B are diagrams for explaining the function of the extension portion 14 of the anchor 100 according to the present embodiment. FIG. 5A shows a state after construction, and FIG. 5B shows a state after a tensile test. Show.

  As shown in FIG. 5A, the anchor 100 according to the present embodiment has a tapered shape in which the inner surface 14 a of the expansion portion 14 becomes thinner toward the distal end 10 b side of the sleeve 10. On the other hand, the tapered surface 22a of the anchor bolt 20 has a tapered shape that narrows the outer diameter toward the base 21b side, opposite to the expanded portion 14.

  Based on such a configuration, when the tapered extended portion 14 expands along the tapered surface 22a, the contact area of the surface of the expanded portion 14 with the inner surface 61a of the lower hole 61 increases. Therefore, the biting part 25 of the expansion part 14 realizes high construction reliability by generating a large frictional force by biting into the inner surface 61a of the lower hole 61 in a wedge shape.

  Further, when a tensile force is applied to the anchor 100 (when a tensile test is performed), as shown in FIG. 5B, the side surface 22b of the head 22 that is a surface parallel to the inner surface 61a of the lower hole 61 is expanded. By entering the inner surface 14a of the portion 14 into a wedge shape, the tip of the expanded portion 14 changes to a large barrel-shaped expanded shape, and the biting portion 25 of the expanded portion 14 bites into the inner surface 61a of the lower hole 61, resulting in a large resistance force. Generate (frictional force).

  Therefore, the anchor 100 according to the present embodiment includes the tapered extension portion 14 and the head portion 22 having the tapered surface 22a, so that the anchor bolt 20 is broken by a greater resistance than the conventional sleeve driving type anchor. Experiments have confirmed that higher tensile performance can be achieved that reaches strength.

  By the way, conventionally, when constructing a sleeve driving type anchor, an operator has used hammer response and hitting sound as a guideline for completion of construction. Therefore, depending on the skill difference of the workers, even when the construction is not completed normally, it is determined that the construction is completed, and there is a possibility that the construction reliability is lowered.

On the other hand, in the present embodiment, the above problem is solved by driving the sleeve 10 using the jig 110.
Specifically, the operator performs a driving operation while confirming the position of the tip 21 a of the bolt portion 21 through the opening window 31 formed in the main body portion 30 of the jig 110. The operator performs a driving operation until the tip 21 a of the bolt portion 21 exposed in the opening window 31 coincides with the construction completion line 32.

  In the present embodiment, the marking lines 32a, 32b, and 32c corresponding to the length of the anchor bolt 20 to be constructed are selected, and the selected marking line is used as a criterion for determining the completion of construction. In the present embodiment, for example, the marking line 32b is used as an indication of completion of construction.

  By using the jig 110, the operator can simply and surely complete the construction of the anchor 100 by visual confirmation. Therefore, since the completion of construction is judged according to the same judgment standard regardless of the skill difference between workers, construction with excellent workability and high reliability can be realized.

  When the construction of the anchor 100 is completed, the sleeve 10 driven by a predetermined amount enters the lower hole 61 and the construction confirmation marker 26 provided on the bolt portion 21 is exposed to the outside. Not only the operator but also the manager can determine the completion of the construction of the anchor 100 by visually confirming the construction confirmation marker 26.

  Conventionally, management and confirmation after anchor construction have been performed. After the anchor construction, since the sleeve and the anchor bolt are hidden in the prepared hole, it cannot be visually confirmed whether the sleeve has been sufficiently driven. Moreover, it was not able to confirm how much the embedding length with respect to the prepared hole of an anchor bolt was after construction.

  In this embodiment, when construction of the anchor 100 is completed, the tip 21a of the anchor bolt 20 is marked by the marking portion 33. Therefore, predetermined information (for example, the embedding length of the anchor bolt 20) can be given only to the anchor bolt 20 in which the driving of the sleeve 10 is normally completed (construction completion).

  Therefore, when performing confirmation after construction, the construction confirmer visually confirms the marking of the tip 21a of the anchor bolt 20 (bolt portion 21), for example, to easily and reliably confirm the embedded length of the anchor bolt 20. Can do.

As described above, according to the anchor construction unit 1 of the present embodiment, it is possible to visually confirm the construction completion of the anchor 100 by using the jig 110.
In addition, since the anchor 100 constructed using the jig 110 is marked with information necessary for confirming the construction such as the embedding length in the anchor bolt 20, the construction confirmer visually observes the marking after construction. Can be confirmed simply and reliably.

  Moreover, the anchor construction unit 1 can obtain high tensile performance that reaches the breaking strength of the anchor bolt 20 by combining the anchor 100. Therefore, according to the anchor construction unit 1, it is possible to stably perform high value-added work with excellent construction management and high construction reliability regardless of the skill of the operator.

(Fixing process)
Finally, as shown in FIG. 4 (d), the nut 80 is fixed to the bolt portion 21 of the anchor bolt 20 after being attached to the attachment 70 to the anchor bolt 20 constructed in the lower hole 61 of the base material 60. Thus, the attachment 70 is fixed to the base material 60.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and appropriate modifications can be made without departing from the spirit of the present invention. .

  For example, in the present embodiment, the construction completion line 32 is used as a guideline for completing the driving operation of the sleeve 10, but the construction completion line 32 may not be provided. For example, it may be determined whether or not the driving operation of the sleeve 10 is completed by measuring the length of the bolt portion 21 exposed in the opening window 31. In this case, the exposure amount of the bolt portion 21 when the driving operation of the sleeve 10 is completed is measured in advance, and the measured value may be used as a threshold value.

  Moreover, in the said embodiment, when the front-end | tip 21a of the volt | bolt part 21 arrived at the construction completion line 32, the marking part 33 automatically marked the structure as an example, However, This invention is not limited to this. For example, the structure which the operator who confirmed that the front-end | tip 21a reached | attained the construction completion line 32 marks the front-end | tip 21a by moving the marking part 33 manually may be sufficient, for example.

  Moreover, in the said embodiment, although the case where the jig | tool 110 was provided with the marking part 30 was mentioned as an example, this invention is not limited to this. For example, the marking unit 30 may be omitted from the configuration of the jig 110. Also in this configuration, the operator can easily confirm the completion of the construction of the anchor 100 by visually confirming the construction of the anchor 100 by driving the sleeve 10 so that the tip 21a of the bolt portion 21 exposed in the opening window 31 coincides with the construction completion line 32. And it can be performed reliably. Therefore, since the completion of construction is judged according to the same judgment standard regardless of the skill difference between workers, construction with excellent workability and high reliability can be realized.

DESCRIPTION OF SYMBOLS 1 ... Anchor construction unit, 10 ... Sleeve, 11 ... Through-hole, 14 ... Expansion part, 20 ... Anchor bolt, 22 ... Head, 23 ... Convex member, 26 ... Construction confirmation marker (construction completion suggestion part), 30 ... Main body , 31 ... opening window, 32 ... construction completion line (injection amount suggestion part), 33 ... marking part, 60 ... base material, 61 ... pilot hole (anchor construction hole), 100 ... anchor, 110 ... jig.

Claims (12)

An anchor construction jig used for construction of an expanded anchor comprising a cylindrical sleeve having a through-hole and an expanded portion, and an anchor bolt that expands the expanded portion by driving the sleeve,
A main body for applying a driving force during construction to the sleeve;
An anchor construction jig, comprising: an opening window formed on the main body portion and allowing a confirmation of construction completion of the expanded anchor by allowing a part of the anchor bolt to face inside. The anchor construction jig according to claim 1, further comprising a driving amount suggesting portion that is provided at an opening end of the opening window and suggests a driving amount of the sleeve. The anchor construction jig according to claim 2, comprising a plurality of the driving amount suggesting portions. 4. The anchor construction jig according to claim 2, wherein the driving amount suggesting portion is set based on a position of a bolt tip of the anchor bolt that has been constructed by driving the sleeve by a predetermined amount. 5. The jig for anchor construction according to any one of claims 1 to 4, further comprising a marking portion capable of marking the anchor bolt when construction of the expansion anchor is completed. The anchor construction jig according to claim 5, wherein the marking part is detachable from the main body part. The anchor construction jig according to claim 5, wherein the marking portion imparts the marking to a bolt tip of the anchor bolt. An expansion anchor including a cylindrical sleeve having a through-hole and an expansion portion, a bolt portion and a head, and an anchor bolt for expanding the expansion portion by the head by driving the sleeve;
An anchor construction unit comprising the anchor construction jig according to any one of claims 1 to 7. The anchor construction unit according to claim 8, wherein the anchor bolt has a construction completion suggesting portion that suggests a state where construction is completed by driving the sleeve by a predetermined amount. The anchor construction unit according to claim 8 or 9, wherein the bolt portion has a tip thereof engraved with predetermined information regarding the anchor bolt. The anchor construction unit according to any one of claims 8 to 10, wherein the anchor bolt includes a convex member provided at a tip of the head and having an outer diameter smaller than that of the head. The anchor construction unit according to claim 11, wherein the convex member is detachable from the head.

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