JP7115678B2 - Anchor fixing strength control method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a fixing strength management method for anchors fixed to a building frame such as a concrete structure.

Various screws such as bolts and screws for fixing interior materials, reinforcing materials, and other objects to be fixed to the framework of various structures and buildings such as columns, beams, ceilings, foundations, etc. An anchor made of a member or the like is used.

Anchors made of this screw member may be embedded and fixed in the building frame when the concrete hardens (hereafter, this embedded anchor is simply referred to as an "embedded anchor"). There are also those that are constructed later on the existing concrete frame or the base material to be fixed such as bedrock and stone, and are called "post-installed anchors".

For post-installed anchors, anchor holes are first made using a drill or other drilling tool in the building frame such as concrete, which is the base material to be fixed, and screw members are fixed in the anchor holes via a bonding agent such as adhesive. There is a type called a "chemical anchor" (see, for example, Patent Document 1, Patent Document 2, page 6, paragraphs 0045 to 0047, etc.). In this chemical anchor, the inner surface of the anchor hole is shaved by the helical thread formed on the outer periphery of the main body shaft of the anchor threaded portion to form a helical thread groove. By interposing a binder between the screw member and the anchor hole as well as the engagement with the screw member, there is also a method in which the fixing strength and durability of the screw member to the base material to be fixed are further enhanced (Patent Document 3, Fig. 3 etc).

In addition, there is also a type called an "expansion-type (drive-in) anchor" in which a part of the screw member expands in diameter within the anchor hole and exerts a retaining function against the inner surface of the anchor hole (Fig. 4 of Patent Document 4). 1st prize).

In such an anchor, the fixing strength to the base material to be fixed is generally confirmed by the pull-out strength of the screw member from the base material to be fixed in the axial direction. The pull-out strength of a screw member is usually measured using a hydraulic load-applying device (center hole jack, etc.). It is determined by how

However, the setting of the load application device for performing this pull-out test is very complicated and takes time and labor, and the load application device is very heavy, which requires heavy labor. In particular, when working in an upward posture, such as when working on the inner walls of tunnels or ceilings, handling the load bearing device becomes even more difficult and time-consuming. For this reason, carrying out a pull-out test on a large number of anchors has a great impact on work processes and work costs. This point is the same in the case of a diameter-expanding anchor in which a part of the screw member is diameter-expanded within the anchor hole.

In addition, by providing a pintail portion (a Torsia type bolt) that breaks at a predetermined rotational torque at the rear end of the anchor screw portion, it is possible to easily manage the fixing strength to the base material to be fixed (Patent Document 3, paragraph 0060, FIG. 3, etc.).

JP-A-8-226427 JP-A-2001-89716 JP 2016-56571 A JP-A-08-197448

When anchors are used to fix objects such as interior materials, reinforcing materials, and other various types of equipment to the framework of pillars, beams, ceilings, foundations, etc. of various structures and buildings, anchors are used not only during construction, but also during construction. It is also necessary to measure (manage) the fixing strength of the anchor at regular intervals after construction, and to measure the fixing strength (fixing strength) of the interior material, reinforcing material, and other objects to be fixed by the anchor.
However, in the past, the fixing strength of such anchors was not measured except by the pull-out test, and was mainly performed by percussion (sound test) or visual observation. This percussion, etc. requires skill and lacks accuracy.
Further, in the torque management of Patent Document 3, once the pintail portion is cut, the pintail portion cannot be used again for torque management.

Accordingly, an object of the present invention relates to an anchor made of a screw member that is fixed to a skeleton of a concrete structure or the like, and to enable easy management of the fixing strength repeatedly and over a long period of time after the anchor is fixed. That is.

In order to solve the above problems, the present invention provides a fixing strength management (measurement) method for an anchor inserted and fixed in a base material to be fixed such as concrete, wherein a torque management member is provided at the rear end of the anchor. A detachably connected torque management member is a first member that is not relatively rotatable about an axis with respect to the anchor when connected to the anchor, and a management for managing fixing strength to the base material to be fixed. A second member to which a torque can be input, and a torque management breaking part provided between the first member and the second member, and breaking the first member and the second member when a predetermined management torque is input. and, after connecting the torque management member to the anchor via the first member, inputting the management torque to the anchor via the second member, and separating the first member and the second member at the torque management breaking portion An anchor anchoring strength management method was adopted in which the anchor anchoring strength to the base material to be anchored is evaluated by breaking (cutting) the anchor.

Evaluation of the fixing strength can be performed many times by replacing the torque management member, and thus can be performed periodically. The period is appropriately set according to empirical rules such as 1 year, 2 years, 5 years, 10 years, etc.
However, the anchor fixing strength management method of this configuration can also be used in the case of imparting a predetermined fixing strength at the initial stage of fixing the anchor to the base material to be fixed. That is, after or before fixing the object to be fixed to the anchor, the torque management member is connected to the anchor via the first member, the management torque is input to the anchor via the second member, and the torque management breaking portion This is because if the first member and the second member are broken in , the anchor is fixed to the base material to be fixed with a fixing strength capable of withstanding a torque equal to or greater than the management torque.

As for the timing of connecting the torque management member to the anchor through the first member, the torque management member is connected to the anchor immediately after the initial fixing strength is measured. The existing torque management member may be used for the anchorage strength measurement, or the torque management member may be connected to the anchor for each anchorage strength measurement.

The connection structure between the anchor rear end and the torque management member may adopt various arbitrary structures as long as the rotational torque can be transmitted. The torque management member is fitted in the connection hole and is detachable, and when attached, it is integrated around the axial direction, or the inner surface of the connection hole has a female thread, The first member may employ a configuration including a male threaded portion that engages with the female threaded portion.
The cross-sectional shape of the connection hole may be any shape as long as the rotational torque can be transmitted. For example, the cross-section is non-circular such as polygonal or elliptical, and the first member has a cross-sectional shape that engages with the inner surface of the connection hole. .

In these connection structures, it is preferable that the torque management breaking portion is arranged outside the connection hole. In this way, after breaking (after cutting the first member and the second member), at least a part of the broken portion protrudes from the connecting hole from the rear end of the anchor. This is because the one member can be easily taken out from the connecting hole. When the first member is taken out, the torque management member can be inserted into the connection hole again, and the fixing strength of the anchor to the base material to be fixed can be evaluated by the torque management member.

As another example of the connection structure between the anchor rear end and the torque management member, the connection portion of the torque management member includes an engagement shaft portion projecting from the axial rear end of the anchor, and the torque management member is the engagement shaft portion. It is possible to adopt a configuration in which the device is attachable to and detachable from the body and integrated around the axial direction at the time of attachment. The cross-sectional shape of the engaging shaft portion may be any shape as long as it can transmit rotational torque. It shall have a concave portion (engagement hole).
Further, the engaging shaft portion may be a screw shaft, and in this case, the first member shall have a concave portion (engagement hole) that can be threadedly engaged with the screw shaft. The screwing direction of the screw shaft may be left or right, but is preferably opposite to the screwing direction of the threaded portion (screw member) of the anchor. For example, if the threaded portion of the anchor is right-handed, the screw shaft is left-handed. This is because, with reverse threads, torque management is an evaluation of fixing strength around threads in the direction in which the anchor is pulled out.

In each of the above configurations, if the first member of the torque management member remains at the rear end of the anchor after each fixing strength is measured (evaluated), the first member may be removed from the rear end of the anchor by an appropriate means. It's fine, but if there is no problem, you can leave it as it is. In any case, it is preferable to provide a cap on the rear end of the anchor to prevent corrosion or the like of the rear end of the anchor. When this cap is fitted, rainwater or the like can be prevented from entering the fractured portion for torque management, the connection hole, etc., and it becomes rust-proof. The connection between the rear end and the torque management member can be easily made.

The present invention relates to an anchor fixed to a building frame such as a concrete structure, and enables easy management of fixing strength after the anchor is fixed.

1 shows an embodiment of an anchor fixing strength management method according to the present invention, (a) being a cross-sectional view, and (b) being an enlarged view of a main part of (a). 1 shows the same embodiment, (a) is a plan view of the anchor, (b) is a front view of the anchor, (c) is a bottom view of the anchor, (d) is a front view of the torque management member, and (e) is torque management. Perspective view of member (a) to (f) are cross-sectional views showing the construction method until the anchor of the same embodiment is fixed to the base material to be fixed. Other embodiments are shown, (a) is a plan view of the anchor, (b) is a front view of the anchor, (c) is a bottom view of the anchor, (d) is a front view of the torque management member, (e) is the torque Perspective view of management member Another embodiment is shown, (a) is a plan view of the anchor, (b) is a front view of the anchor, (c) is a bottom view of the anchor, and (d) is a front view of the torque management member. Another embodiment is shown, (a) is a plan view of the anchor, (b) is a front view of the anchor, (c) is a bottom view of the anchor, and (d) is a front view of the torque management member. Another embodiment is shown, (a) is a plan view of the anchor, (b) is a front view of the anchor, (c) is a bottom view of the anchor, and (d) is a front view of the torque management member. Another embodiment is shown, (a) is a plan view of the anchor, (b) is a front view of the anchor, (c) is a bottom view of the anchor, and (d) is a front view of the torque management member. Cross-sectional view showing still another embodiment Cross-sectional view showing the action of still another embodiment Front view of still another embodiment

Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, anchor holes B are drilled in a skeleton (hereinafter referred to as "fixed base material C") such as concrete to be fixed target base material using a drill or the like, and the anchor holes B are drilled. It is a "post-installed anchor" that inserts and fixes an anchor 10, which is a shaft-shaped screw member. In particular, it is a chemical anchor in which a binder A such as an adhesive is interposed between the anchor 10 and the inner surface of the anchor hole B.

The anchor 10 of this embodiment includes a screw screw (screw member) having a main body male threaded portion 13 and a rear end male threaded portion 12 in order from the tip side entering into the anchor hole B of the base material C to be fixed toward the rear end side. ). A torque management member 20 is connected to the rear end of the anchor 10 .

The main body male threaded portion 13 includes a threaded portion 13a having a relatively high thread height (hereinafter referred to as a “first threaded portion 13a”) and a second threaded portion having a relatively low thread height. It is a double-start screw that alternately includes two thread portions 13c (hereinafter referred to as "second thread portions 13c"). In other words, there are two pairs of spiral portions that constitute the screw thread, and the height of the screw member 10 along the axial direction advances by a distance corresponding to two screw threads while the screw member 10 makes one rotation about the axis.

As shown in FIG. 1B, the bottom surface of the trough portion 13b between the first thread portion 13a and the second thread portion 13c is formed to have an arcuate cross section along the axial direction. The pitch of the first thread portion 13a is set to be the same as that of the second thread portion 13c.

A distal end portion 14 of the screw member 10 is located on the distal end side of the body male screw portion 13 . The tip portion 14 has a tapered truncated cone shape. A side surface 14a of the tip portion 14 is a conical surface that gradually tapers toward the tip, and an end surface 14b of the tip portion 14 is a flat surface having a surface direction perpendicular to the axial direction. The shape of the distal end portion 14 can be varied, and may be, for example, cylindrical, conical, prismatic, truncated pyramidal, pyramidal, or the like.

The rear end male screw portion 12 has a screw thread portion 12a made of a male screw. By screwing a fixing nut (not shown) into the thread portion 12a, various to be fixed (not shown). The rear end male threaded portion 12 may have any structure as long as it can receive a predetermined load, and is not limited to a male thread. Other structures are also possible.

The anchor 10 is entirely made of carbon steel, and in particular, the body male screw portion 13 is quenched. The material of the anchor 10 is not limited to carbon steel, and stainless steel and other metals can also be used. The material of the torque management member 20 can also be the same as that of the anchor 10 .

However, the screw thread portion of the body male screw portion 13 is required to have a self-tapping function that bites into the inner surface of the anchor hole B of the base material C to be fixed. For this reason, the material of at least the thread portion (in this embodiment, the first thread portion 13a, which is a thread portion having a relatively high thread height) that requires the self-tapping function is , is preferably made of a material relatively harder than the base material C to be fixed.

The thread portion of the main body male thread portion 13 enters into the thread groove D formed in the inner surface of the anchor hole B by the self-tapping function, and the main body male thread portion 13 and the thread groove D are engaged with each other. Further, a binder A such as an adhesive is interposed between the outer surface of the main body male screw portion 13 and the inner surface of the anchor hole B, and the binder A hardens, thereby fixing the main body male screw portion 13 to the base material to be fixed. C, and the anchor 10 is fixed to the base material C to be fixed.

Whether or not the body male threaded portion 13 (anchor 10) of the anchor 10 is fixed to the base material C to be fixed is determined before fixing the object to be fixed. A torque management member 20 made of a member is connected and checked.

The torque management member 20 can be detachably connected to the anchor 10 by a torque management member connection 11 provided on the anchor 10 . In this embodiment, the torque management member connection portion 11 is a connection hole 11a having a regular hexagonal cross section, and the torque management member 20 can be attached/detached by inserting/removing the torque management member 20 into/from the connection hole 11a in the axial direction.

As shown in FIGS. 2(d) and 2(e), the torque management member 20 is a first member 21 connected to the anchor 10, and a torque management member 20 for managing the fixing strength of the main body male screw portion 13 to the base material C to be fixed. is provided between the second member 22 capable of inputting the management torque of , and the first member 21 and the second member 22, and the first member 21 and the second member 22 are connected by the input of the predetermined management torque It is an integral unit provided with a torque management breaking portion 23 that breaks the gap and separates them from each other.

In this embodiment, the first member 21 has a columnar shape with a regular hexagonal cross section that fits snugly into the connection hole 11a, and the second member 22 also has a columnar shape with a regular hexagonal cross section of the same size and shape. The second member 22 is adapted to fit snugly with a connection tool (holder, socket, etc.) of a torque applying means such as a torque wrench, impact wrench, or the like. The second member 22 does not have to have the same cross-sectional shape as the first member 21 . Also, although the broken portion 23 has a circular cross-section, it may have a polygonal cross-section.

In addition, the length of the anchor (screw member) 10 shown in FIG. , length (depth) of connection hole 11a: L5, gap between rear end male threaded portion 12 and body male threaded portion 13: L6, diameter of threaded portion (first threaded portion) 13a: r1, screw thread Diameter of portion (second thread portion) 13c: r2 Diameter of valley portion 13b: r3 Length of torque control member (pin) 20: b1 Width dimension of torque control member (pin) 20: t Torque The length of the first member of the management member (pin) 20: b2, the length of the second member 22: b3, the length of the breaking part 23: b4, the same diameter: r, etc. are the properties of the base material C to be fixed. , the material of the anchor 10, the weight of the object to be fixed, etc., and may be appropriately set according to empirical rules.
For example, when the base material C to be fixed is concrete, the fixed object is a heavy object such as a ceiling plate, and the anchor 10 is SCM425 (chromium molybdenum steel), L1 = 160 mm, L2 = 55 mm, L3 = 100 mm, L4 = 4.5 mm. , L5=10 mm, L6=0.5 mm, t, r=9 mm, b1=32 mm, b2, b3=15 mm, b4=2 mm, rear end male screw portion 12=M16, and the like.

FIGS. 3(a) to 3(f) show a construction method for fixing the anchor 10 having this configuration in the anchor hole B of the base material C to be fixed, and a fixing structure of the screw member by the construction. The fixing structure of the anchor 10 of this embodiment consists of the anchor hole B formed in the base material C to be fixed, the anchor 10 (main body male screw portion 13), the rear end male screw portion 12, and the inner surface of the anchor hole B. It is a structure with a binder A interposed therebetween.

As shown in FIG. 3(a), an anchor hole B is bored in the base material C to be fixed, and the inside of the anchor hole B is cleaned by sliding due to vertical movement and rotation of the brush b or by blowing air (same as above). FIG. (b)), the binder A is injected into the hole B (the same figure (c)). After that, as shown in FIG. 3(d), the main body male screw portion 13 of the main body shaft member 15 is screwed into the anchor hole B into which the binder A is injected, and the helical thread portion of the main body male screw portion 13 is formed. The inner surface of the anchor hole B is shaved by the self-tapping function to form a helical screw groove D. As shown in FIG.

When screwing the main body male threaded portion 13 into the base material C to be fixed, as shown in FIG. The connection tool of the torque applying means is fitted to apply rotational torque for screwing. Here, since the direction of the male thread of the body male threaded portion 13 and the direction of the male thread of the rear end male threaded portion 12 are the same direction (right-hand thread in this embodiment), the rotational torque for screwing (clockwise rotation) Torque) prevents the tightening nut 16 from loosening from the rear end male threaded portion 12 .

The helical thread groove D is formed in such a manner that there is a minute gap between the inner surface of the thread groove D and the outer surface of the thread portion of the body male thread portion 13 . That is, in the process of self-tapping, as the body male screw portion 13 rotates around its axis, the cross section of the thread groove D is formed to be slightly larger than the cross section of the thread portion. In FIG. 1(b), the cross section of the thread groove D has an isosceles trapezoidal shape, and the cross section of the thread portion 13a has a triangular shape. The top of the first screw thread portion 13a and the bottom surface of the trapezoidal thread groove D opposite thereto are in contact or face each other with a slight gap. Also, the flank of the first thread portion 13a and the slope of the trapezoidal thread groove D facing the flank face each other with a gap therebetween.

The thread portion of the main body male thread portion 13 enters the thread groove D, and the binder A is interposed in the space between the inner surface of the thread groove D and the outer surface of the thread portion 13a of the main body male thread portion 13. there is Further, the binder A is interposed between the outer surface of the screw member 10 and the inner surface of the anchor hole B also at locations other than the thread groove D and the thread portion 13a.

In this embodiment, with respect to the height of the thread of the first thread portion 13a and the inner diameter d of the anchor hole B, the depth of entry of the thread into the thread groove D is set to h (Fig. 1(b) )reference). The height of the screw thread and the ratio of the depth h to the inner diameter are appropriately determined depending on the type of base material C to be fixed, the fixing strength required, and the like.

In this way, by screwing the body male threaded portion 13 of the anchor 10 into the anchor hole B (see arrow x in FIG. 3(d)), the helical threaded portion 13a of the body male threaded portion 13 is inserted into the anchor hole B. and cuts the inner surface of the anchor hole B by a self-tapping function to form a helical screw groove D in the inner surface. At this time, the screw thread portion 13a enters into the screw groove D. As shown in FIG. At the same time, the binder A is spread over the space between the outer surface of the screw member 10 and the inner surface of the anchor hole B.

The adhesive force between the main body male screw portion 13 and the fixing target base material C due to the binder A, and the frictional force between the main main body male screw portion 13 and the fixing target base material C due to the biting of the thread portion 13a into the inner surface of the anchor hole B. will work together, and the fixing strength and durability of the anchor 10 to the base material C to be fixed can be further enhanced.

Here, by making the main body male threaded portion 13 a double-threaded thread having two threaded portions with different thread heights, an effect of smooth filling of the binder A is exhibited. That is, the higher screw thread portion 13a exerts a self-tapping function to form a screw groove D in the inner surface of the anchor hole B, and the lower screw thread portion 13c allows the outer surface of the anchor 10 and the inner surface of the anchor hole B to be connected. The binder delivery function of spreading the binder A throughout the space between them is exhibited, and the binder A is smoothly filled.

As the binder A, any material can be freely used as long as it can exhibit a predetermined strength and durability after solidification. For example, a two-liquid mixing type organic adhesive that uses an uncured resin and a curing agent that cures the resin, or an uncured cementitious material and an action that accelerates the curing of the cementitious material. It is possible to use a two-liquid mixing type inorganic fixing agent using a curing accelerator or the like having a Alternatively, well-known adhesives compatible with stone materials such as concrete and metal materials can also be used.

In the embodiment, as the binder A, a two-liquid mixed organic adhesive is used. After drilling the anchor hole B in the base material C to be fixed and before screwing the body male threaded portion 13 of the anchor 10 into the anchor hole B, a fixing agent in a state of mixing two liquids is injected into the anchor hole B. Keep Alternatively, after screwing the screw member 10 into the anchor hole B to some extent, the adhesive may be injected.

Further, the binder A may be encapsulated in glass or resin capsules. By inserting a capsule (not shown) into the anchor hole B in advance and screwing the anchor 10 in that state, the capsule is broken at the distal end portion 14, and the binder A inside is removed from the outer surface of the anchor 10. and the inner surface of the anchor hole B. When the binding agent A hardens, the anchor 10 is immovably fixed in the anchor hole B, resulting in the state shown in FIG. 3(d).

Here, if the shape of the distal end portion 14 is tapered as described above, the resistance when screwing the anchor 10 into the anchor hole B is reduced, and in particular, the binder A that is encapsulated is used. In some cases, the rupture of the capsule is smooth.

As shown in FIG. 3(d), the anchor 10 is fixed to the base material C to be fixed, and the rear end male screw portion 12 protrudes outward from the surface of the base material C to be fixed. Since the screw thread portion 12a of the rear end male screw portion 12 protrudes, after the main body male screw portion 13 (anchor 10) is fixed to the base material C to be fixed, the screw thread portion 12a of the rear end male screw portion 12 protrudes. A fixing nut can be screwed into the to fix the object to be fixed as described above. The tightening nut 16 may be loosened and removed from the rear end male screw portion 12 at an appropriate time before fixing the object to be fixed, and the tightening nut 16 may be used for fixing.

Before fixing the object to be fixed, whether the anchor 10 is fixed to the base material C to be fixed with the required strength is checked by checking a separate member from the anchor 10 as shown in FIGS. The torque management member 20 consisting of is connected and confirmed.

That is, as a fixing strength management method for evaluating the fixing strength of the anchor 10 to the fixing target base material C, first, after fixing the main body male thread portion 13 of the anchor 10 to the fixing target base material C, the torque management member of the anchor 10 The torque management member 20 is connected to the connecting portion 11 (see arrow y in FIG. 3(e)). After that, the control torque Z is input to the second member 22 of the torque control member 20 (see arrow z in FIG. 3(f)).

The input of the management torque can be performed by fitting a connection tool (holder, socket, etc.) of the torque applying means to the second member 22 and applying the management torque Z around the axis to the second member 22. . The control torque Z is in the direction in which the main body male screw portion 13 is loosened from the fixing target base material C, that is, in the direction opposite to the tightening torque.

Between the first member 21 and the second member 22, there is provided a breaking portion 23 for torque management, which is a neck portion with a slightly smaller diameter r. Therefore, after the main body male screw portion 13 is fixed and fixed to the base material C to be fixed, if a predetermined control torque Z is applied to the second member 22, the first member 21 and the first member 21 are connected to each other at the torque control fracture portion 23. It is designed to break (separate) from the second member 22 (Fig. 3(f)). Therefore, if the torque management breaking portion 23 is broken without the anchor 10 rotating with respect to the fixing target base material C, the anchoring strength of the anchor 10 to the fixing target base material C is appropriate, and the torque controlling torque management breaking portion 23 is broken. If the anchor 10 rotates around the axis in the direction in which the anchor 10 is loosened without breaking at the breaking portion 23, it can be evaluated that the fixing strength is not appropriate. The inspection of the fixing strength management may be performed using the tool of the torque applying means such as an electric motor as described above, or may be manually performed using a tool of the torque applying means such as a manual torque wrench. may

In this way, in order to evaluate and manage the fixing strength of the anchor 10 to the base material C to be fixed, the torque management member 20, which is a separate member from the anchor 10, is adopted. The fixing strength can be easily managed without complicating the process.
After the evaluation of the fixing strength, after a certain period of time, for example, several months or several years later, the torque management member 20 is connected to the torque management member connecting portion 11 of the anchor 10, and the fixing strength of the anchor 10 is evaluated by a similar action. can be evaluated. After that, fixing strength evaluation is performed at regular intervals or as needed.

It should be noted that the torque management member 20 can also provide the initial fixing strength of the anchor 10 . That is, when the body male threaded portion 13 of the anchor 10 is screwed into the anchor hole B, the torque management member 20 may be connected to the anchor 10, and the anchor 10 may be rotated by the second member 22 of the torque management member 20. . At this time, the rotation direction of the torque management member 20 about the axis is set to the screwing direction of the anchor 10, and if the management breaking portion 23 is broken, it means that it is fixed (fixed) with the required strength.

In this embodiment, the torque management member connection portion 11 is a connection hole 11a having a hexagonal cross section that opens at the axial rear end of the anchor 10 and extends toward the axial distal end side. form can be adopted.

For example, in the example shown in FIG. 4, the connection hole 11a has a square cross section, and the first member 21 has a square cross section that fits snugly into the connection hole 11a. The first member 21 and the second member 22 do not necessarily have the same size and shape in cross section, but in this example, the second member 22 also has the same size and shape as the first member 21. It has a rectangular cross section. Similarly, the second member 22 has a cross-section that allows a connection tool of a torque applying means such as a torque wrench or an impact wrench to fit snugly.

The cross-sectional shape of the connection hole 11a is not limited to a regular hexagon or a regular square, and may be any shape such as various polygons such as a quadrangle, a pentagon, or an ellipse as long as a tool can be fitted and rotated. That is, the cross section of the first member 21 is non-circular, and the first member 21 has a cross-sectional shape that fits snugly into the connection hole 11a. If the cross-sectional shape prevents relative rotation around the axis, the fixing strength can be managed by the torque management member 20 .

In addition, if the connection hole 11a has a circular cross section and the first member 21 has a circular cross section that fits tightly in the connection hole 11a, or the first member 21 does not engage the inner surface of the connection hole 11a Even in the case of the shape of the first member 21 inserted into the connection hole 11a, by a detent means such as a pin inserted so as to enter the connection hole 11a from the outer peripheral surface of the anchor 10, If the first member 21 and the anchor 10 can be made relatively non-rotatable, the fixing strength can be managed by the torque management member 20 .

Furthermore, for example, in the example shown in FIG. 5, the inner surface of the connection hole 11a is provided with a connecting female screw portion 11b, and the first member 21 is provided with a connecting male screw portion 24 that engages with the connecting female screw portion 11b. configuration. Further, the second member 22 constitutes the head 25 of the bolt. Since the connection female screw portion 11b and the connection male screw portion 24 are opposite to the male screw direction of the main body male screw portion 13 and the rear end male screw portion 12 (left-hand screw in this embodiment), the management torque is By applying (counterclockwise rotation torque), the torque management member 20 is not loosened and detached from the anchor 10 . The configuration of the torque management breaking portion 23 provided between the first member 21 and the second member 22 is the same as in the above example.
When the anchor 10 of this embodiment is screwed into the anchor hole B, a tightening nut 16 is screwed into the rear end male threaded portion 12 and screwed through the nut 16. A nut-shaped portion of the portion 25 may be formed and used to screw in (see reference numeral 31 in FIG. 11).
Further, the connection hole 11a may have a spline structure on the inner surface thereof, and the first member 21 may have a spline shaft shape that fits into the spline hole (see FIG. 8).

In these embodiments, the first member 21 of the torque management member 20 is fitted into a connection hole 11a provided at the axial rear end of the anchor 10 for connection. However, other forms of the torque management member connecting portion 11 are also conceivable.

For example, the outer peripheral surface of the rear end of the anchor 10 in the axial direction is used as the torque management member connection portion 11 having a non-circular cross section such as an ellipse, and the first member 21 of the torque management member 20 is connected to the torque management member having a non-circular cross section. A hole having a cross-sectional shape that fits snugly on the outer peripheral surface of the portion 11 or that can transmit the torque for management may be provided.
For example, as shown in FIG. 6, a regular hexagonal columnar engaging shaft portion 17 protruding from the rear end of the rear end male screw portion 12 is provided, and the first member 21 of the torque management member 20 has the engaging shaft portion 17 It may have an engaging hole 27 for fitting. The engaging shaft portion 17 is not limited to a regular hexagon, and may be any shape such as various polygons such as a quadrangle, a pentagon, and an ellipse as long as a tool can be fitted and rotated. At this time, the engagement hole 27 may of course have a shape into which the engagement shaft portion 17 is fitted, such as a square hole.

In addition, as shown in FIG. 7, on the outer peripheral surface of the rear end of the anchor 10 in the axial direction, a connection male screw portion 17a is formed in a direction opposite to the male screw direction of the main body male screw portion 13 and the rear end male screw portion 12. The first member 21 of the torque management member 20 may be provided with a connection female screw portion (engagement hole) 27a that is screwed onto the connection male screw portion 17a. In this embodiment, when screwing into the anchor hole B, a tightening nut 16 is screwed into the rear end male screw portion 12 and screwing is performed through the nut 16, or the head 25 is screwed into the rear end male screw portion 12. For example, a nut-shaped portion is formed and used for screwing (see reference numeral 31 in FIG. 11).
Further, as shown in FIG. 8, the engagement shaft portion 17 may be a spline shaft 17c, and the first member 21 of the torque management member 20 may have a spline engagement hole 27c into which the spline shaft 17c is fitted. can.

In each of these embodiments, when the torque management member 20 is connected to the anchor 10, the torque management breaking portion 23 is preferably arranged outside the connection hole 11a. If the torque management breakage portion 23 is located outside the connection hole 11a, the torque management breakage portion 23 breaks and the first member 21 and the second member 22 are separated as shown in FIG. 3(f). When separated, the first member 21 remaining in the torque management member connecting portion 11 protrudes from the rear end surface of the anchor 10 . For this reason, the effect that the first member 21 can be easily removed (taken out) from the anchor 10 by grasping the projecting portion can be expected.

As described above, the fixing strength is managed by the managing member 20 in the present invention, the anchor 10 capable of managing the fixing strength, and the screw member fixing structure using the anchor 10 are fixed target base materials such as this embodiment. Not only chemical anchors with screw engagement to C, but also other anchors are applicable.

For example, as shown in FIG. 9, the present invention can also be applied to conventional chemical anchors in which the threads of the anchor 10 do not bite into the base material C to be fixed. For this reason, the main body male screw portion 13 can be a single thread instead of a double thread. In the case of this single-start screw, the screw thread does not have to cut into (tap) the base material C to be fixed.

In addition, in the diameter expansion type (ramming type, see FIG. 1 of Patent Document 4) in which a portion of the anchor 10 expands in the anchor hole B and exerts a retaining function against the inner surface of the anchor hole B, the If the connection structure of the torque management member 20 is configured at the rear end of the anchor, the configuration of the present invention can be achieved, and the effect can be exhibited.

Furthermore, even in the embedded anchor that is embedded and fixed in the building frame when the concrete hardens, if the connection structure of the torque management member 20 is configured at the rear end of the anchor, the configuration of the present invention can be achieved. It goes without saying that

In each of the above-described embodiments, the fixing strength is evaluated by applying a force to rotate the anchor in the pull-out direction. It is preferable that the anchor weakens in anchoring strength due to reverse rotation. However, since it is conceivable that the frame surface around the anchor may collapse due to the rotation of the screw around its axis, and the fixing strength of the anchor may weaken, the rotation direction of the torque management member 20 is not always the opposite of the screwing direction of the anchor when evaluating it. does not have to be In particular, in the case of an embedded anchor that does not have a screw shaft shape, either forward or reverse rotation may be used.

In each of the above embodiments, if the first member 21 of the torque management member 20 remains at the rear end of the anchor after the fixing strength is measured, the first member 21 may be removed from the rear end of the anchor by an appropriate means. It's fine, but if there is no problem, you can leave it as it is. In any case, as shown in FIGS. 10(a) and 10(b), after the fixation evaluation, a cap 30 may be provided at the rear end of the anchor 10 to close the rear end to prevent corrosion or the like. preferable. The cap 30 may be of a screw-in type or a fitting type, and its material may be resin, corrosion-resistant metal, or the like.
When this cap 30 is fitted, rainwater or the like can be prevented from entering the broken portion, the connection hole 11a, etc., and becomes rust-proof. Connection with the torque management member 20 is facilitated. It is preferable to apply an antirust agent to the screw portions 11b, 17a and the like.

By the way, it is also possible to form a flat surface at an arbitrary position in the longitudinal direction of the rear end male screw portion 12 so that the anchor 10 can be easily screwed into the flat surface. For example, in the embodiment of FIG. 7, as shown in FIG. 11, after forming a regular hexagonal prism portion 31 having the same shape as the engaging shaft portion 17 of FIG. A connecting male screw portion 17a is provided at the tip of the regular hexagonal columnar portion 31. As shown in FIG.

10 Anchor 11 Torque management member connection portion 11a Connection hole 11b Connection female thread portion 12 Rear end male thread portion 12a Thread portion 13 Body male thread portion 13a Thread portion (first thread portion)
13b trough portion 13c thread portion (second thread portion)
14 Tip portion 14a Side surface 14b End surface 17 Engagement shaft portion 20 Torque management member 21 First member 22 Second member 23 Torque management breaking portion 24 Connection male screw portion 25 Head 30 Cap A Binder B Anchor hole C Fixed object Base material (concrete)
D screw groove

Claims (6)

A fixing strength management method for an anchor (10) inserted and fixed into an anchor hole (B) of a base material (C) to be fixed such as concrete, comprising:
A torque management member (20) is detachably connected to the rear end of the anchor (10), and the torque management member (20) is an engaging shaft portion (17) protruding from the axial rear end of the anchor (10). ), and in a state in which the engagement hole (27) is connected to the engagement shaft (17) , the anchor (10) cannot rotate relative to the axis. a first member (21), a second member (22) capable of inputting a management torque (Z) for managing the fixing strength to the base material (C) to be fixed, and the first member (21 ) and the second member (22), and for torque management that breaks the first member (21) and the second member (22) upon input of the predetermined management torque (Z) a breaking portion (23), wherein the outer diameter of the second member (22) is set smaller than the outer diameter of the portion of the first member (21) provided with the engagement hole (27),
After connecting the torque management member (20) to the anchor (10) via the first member (21), the management torque (Z) is applied to the anchor (10) via the second member (22). , and by breaking the first member (21) and the second member (22) at the torque management breaking portion (23), the base material (C) to be fixed of the anchor (10) An anchor anchoring strength management method for evaluating anchoring strength against. The anchor fixing strength management method according to claim 1, wherein the fixing strength of the anchor (10) to the base material (C) to be fixed by the torque management member (20) is evaluated periodically. The threaded portion (13a) of the body male threaded portion (13) of the anchor (10) enters the threaded groove (D) in the anchor hole (B), and the inner surface of the threaded groove (D) and the threaded portion The main body male screw portion (13) is fixed to the fixing target base material (C) with a binder (A) interposed between the outer surface of (13a), and the main body male screw portion (13) is fixed to the fixing target base material. 3. The anchor fixing strength management method according to claim 1 or 2, wherein after fixing to the material (C), the fixing strength is evaluated by inputting the management torque (Z) to the second member (22). The engaging shaft portion (17) has a non-circular cross-section, and by fitting the engaging shaft portion (17) into the engaging hole (27), the torque management member (20) can move toward the anchor (10). ), the anchor fixing strength management method according to claim 1 or 2. The engagement shaft portion (17) is a screw shaft, and the torque management member (20) is screwed into the engagement hole (27) to engage the anchor (10). ), the anchor fixing strength management method according to claim 1 or 2. 6. The anchor fixing strength control method according to any one of claims 1 to 5 , wherein a cap (30) is fitted to the rear end of the anchor (10) after the torque control breaking portion (23) is broken.

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