JP3819013B2 - Anchor tightening method for civil engineering and nut with anchor cap for civil engineering - Google Patents

Description

  The present invention relates to a method for fastening an anchor for civil engineering such as a lock bolt used for stabilizing a slope and the like, and a nut with a cap for an anchor for civil engineering used in the anchor fastening method.

Known anchors for civil engineering include so-called ground anchors and lock bolts made of PC steel wires, PC steel strands, deformed PC steel rods, etc. for transmitting a tensile force. With respect to the connecting portion of this type of anchor with the head, a cylindrical auxiliary sheath that protects the upper part of the anchor is formed, and the head side of this auxiliary sheath is inserted into an insertion hole formed in the bearing plate, and the upper end The lower concave spherical surface that protrudes from the surface of the bearing plate, presses the upper end of the bearing plate through the convex spherical washer when the anchor is tightened by the fastener, and further fits the cap to the convex spherical washer. It is known to screw the outer periphery of the washer to cover the head of the anchor and store a rust preventive agent in the cap (Patent Document 1). By the way, in the case of this prior art, the anchor tightening member and the cap that covers the anchor head are composed of separate members, so that in addition to the anchor tightening operation, a cap mounting operation is required. In addition, it took time and labor for the work, and the cap was structured to cover the fastening member. Therefore, the cap was increased in size, and the manufacturing cost was increased and a large amount of rust preventive was required.
Japanese Patent Laid-Open No. 9-195272

  In view of the conventional technical situation as described above, the present invention can be integrated with a fastening portion for a civil engineering anchor and a cap that covers the anchor head, and the components can be reduced in size. The object is to provide a good engineering anchor fastening technique.

  In the present invention, in order to solve the above-mentioned problem, a lower spherical portion that transmits a tensile force acting on a civil anchor such as a lock bolt to the bearing plate is provided on the bearing plate side, and the lower spherical portion is provided to the lower spherical portion. A nut with a cap for an anchor that has an upper spherical portion that can be fitted in the lower portion, and has a female screw that can be screwed into the anchor inside, and a cap portion that integrally covers the upper portion of the anchor. The technical means of tightening the anchor in a state where the upper spherical portion formed at the lower part of the nut with cap for the anchor was fitted to the lower spherical portion installed on the bearing plate side was employed.

According to the present invention, the following effects can be obtained.
(1) In the nut with a cap for an anchor according to the present invention, a female screw that can be screwed into the anchor is formed inside, and a cap portion that covers the upper portion of the anchor is integrally formed. Since the attachment of the cap portion is completed at the same time, the workability can be greatly improved.
(2) Since the nut with a cap for an anchor according to the present invention is configured to be screwed and tightened directly to the anchor via a female screw formed therein, Compared with a cap that covers the outer side of the constituting tightening nut or the like, the size can be reduced by the amount of the tightening nut or the like.
(3) In the present invention, the anchor is tightened in a state in which the upper spherical portion formed in the lower portion of the nut with the cap for the anchor and the lower spherical portion installed on the bearing plate side are fitted. Even when the axis is inclined with respect to the normal of the bearing plate, it can be easily dealt with by sliding on the fitting surface of these spherical portions.
(4) As described above, when the axis of the anchor is inclined with respect to the normal of the bearing plate, the configuration is made by sliding on the fitting surface of the spherical portion. Since the axis of the nut with cap is similarly inclined, there is no need to provide a dimensional allowance for the inclination of the anchor on the cap side as in the prior art, and this point is also extremely effective for reduction.
(5) Furthermore, when the rust preventive agent is filled inside by reducing the size of the nut with cap for anchor, the amount of use can be reduced.

  The nut with a cap for an anchor according to the present invention can be composed of a stainless material, or a surface treated for rust prevention by galvanization, electroplating, resin coating, or the like. The nut with cap for the anchor forms an upper spherical surface portion that can be fitted to a lower spherical surface portion that is installed on the bearing plate side at a lower portion, and internally forms a female screw that can be screwed to the anchor. The cap portion is formed by integrally forming an upper portion of the anchor. Incidentally, the shape of the cap part can be circular or hexagonal like the nut part. In addition, the lower spherical portion installed on the bearing plate side and the upper spherical portion installed on the lower portion of the nut with the cap for the anchor consist of a combination of a concave spherical portion and a convex spherical portion, which is concave. It may be convex or convex. The spherical portion installed on the bearing plate side can be formed separately from the washer installed on the bearing plate or as an integral washer.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing a first embodiment in which a lock bolt made of a deformed PC steel rod in the form of a fully threaded bolt is adopted as an anchor as an embodiment of the present invention and applied to an anchor of a type covered with a sheath. FIG. 2 is an enlarged view showing the main part. FIG. 3 is an explanatory diagram of parts showing a nut with an anchor cap according to the present invention, in which (a) is a sectional view, (b) is a front view, and (c) is a left side of (b). FIG. 4D is a right side view of FIG.

  In the figure, reference numeral 1 denotes an anchor. In this embodiment, a lock bolt made of a deformed PC steel rod having a full thread bolt shape is used and covered with a sheath 3. The anchor 1 and the sheath 3 are inserted into a drilling hole 5 formed in the ground 4 such as a slope, and the anchor 1 is fixed to the ground 4 by a grout material 6 injected into the inside and outside of the sheath 3.

  The anchor 1 in the present embodiment is inserted through an insertion hole 7 a formed in the bearing plate 7 so that the head 1 a side protrudes from the surface of the bearing plate 7. A washer 9 is placed on the pressure bearing plate 7 via a washer 8, and this washer 9 has a concave lower spherical surface portion 9b around an insertion hole 9a. A nut 10 with an anchor cap is screwed onto the head 1 a of the anchor 1.

  In the present embodiment, the nut 10 with an anchor cap is configured so as to be filled and stored with rust preventive oil or the like as a rust preventive agent. The nut 10 is screwed to the cap portion 10a and the head 1a of the anchor 1. The part 10b is integrally formed. The cap part 10a has a bag-like space for containing a rust preventive agent, and a hole 10a1 for venting air or discharging excess oil is formed at a tip part of the cap part 10a. The stopper bolts 12 are screwed to be closed. The number of the holes 10a1 is not limited to one and may be two. A gap between the cap 10 a and the head of the plug bolt 12 is sealed by an O-ring 20.

  The nut portion 10b has a convex upper spherical surface portion 10b1 at the lower portion, and a female screw 10b2 is formed therein, and the female screw 10b2 of the nut portion 10b is screwed into the head 1a of the anchor 1 and tightened. Thus, the convex upper spherical surface portion 10b1 of the nut portion 10b is securely crimped and fixed to the concave lower spherical surface portion 9b formed on the washer 9 on the pressure bearing plate 7 side.

  As the nut 10 with the cap for the anchor, a stainless steel or a surface treated for rust prevention by galvanization, electroplating, resin coating or the like is used. The washer 9 and the washer 8 are processed in the same manner. Incidentally, the cap portion 10a has a certain margin in length so that the anchor 1 can be accommodated if the length of the anchor 1 protruding from the surface of the bearing plate 7 is within a certain range.

  At the time of use, the nut portion 10b is turned up and grease-like rust preventive oil is filled up to a position up to about half of the nut portion 10b. Next, when the nut 10 with an anchor cap is screwed onto the head 1a of the anchor 1 with the plug bolt 12 removed from the hole 10a1, air in the cap portion 10a and excess rust preventive oil are removed. It comes out of the hole 10a1. After the nut 10 with an anchor cap is tightened, the stopper bolt 12 is screwed into the hole 10a1 to complete the operation. The outer shape of the cap portion 10a constituting the nut 10 with anchor cap may be circular or hexagonal like the nut portion 10b.

  As described above, the nut 10 with a cap for the anchor is formed by forming the upper spherical surface portion 10b1 of the nut portion 10b on the washer 9 on the bearing plate 7 side by screwing and tightening the nut portion 10b to the head portion 1a of the anchor 1. Crimped and fixed to the lower spherical surface portion 9b. Incidentally, since the cap cap nut 10a and the nut portion 10b are integrally formed, the anchor cap nut 10 has a small number of parts and can be easily assembled to the anchor 1. Further, since the cap portion 10a is integrated with the nut portion 10b having the spherical surface portion 10b1 at the lower portion, it is possible to cope even if the bearing plate 7 and the anchor 1 are not vertical, and the cap portion 10a has this angle. It is not necessary to increase the size in anticipation of the deviation. That is, the inner diameter of the cap portion 10a of the anchor cap-equipped nut 10 need only be slightly larger than the outer diameter of the anchor 1. Thus, the nut 10 with a cap for an anchor can make the inner diameter of the cap portion 10a slightly larger than the outer diameter of the head 1a of the anchor 1, so that the amount of the rust inhibitor used can be reduced as compared with the conventional case. It is economical.

  In addition, since the sheath 3 can prevent water from entering between the nut 10 with the anchor cap 10 and the washer 9 and between the washer 8 and the washer 9 with the sheath 3, The rust prevention function of the entire head is more reliable.

  Next, a second embodiment of the present invention will be described. FIG. 4 is an enlarged view showing a main part of the second embodiment of the present invention. This embodiment is a modification of the above-described embodiment shown in FIGS. 1 to 3 and has the same basic configuration, in which the washer 8 and the washer 9 are integrally formed. As described above, in this embodiment, the washer 8 and the washer 9 are integrally formed, so that the number of parts is small, and attachment is easy.

  Next, a third embodiment of the present invention will be described. FIG. 5 is a cross-sectional view showing a third embodiment of the present invention, and FIG. 6 is an enlarged view showing an essential part thereof. Incidentally, also in the present embodiment, as in the above-described embodiment, a case where a lock bolt made of a deformed PC steel rod in the form of a fully threaded bolt is employed as an anchor and applied to an anchor of a type covered with a sheath is shown. In the following description of this embodiment, the same components as those in the embodiment shown in FIGS.

  The nut 10 with an anchor cap of the present embodiment has a concave upper spherical surface portion 10c1 at a lower portion of a nut portion 10c that is screwed to the head portion 1a of the anchor 1 formed integrally with the cap portion 10a. . Also, a female screw 10b2 is formed inside, and the female screw 10b2 is screwed into the head 1a of the anchor 1 and tightened to tighten the upper spherical surface portion 10c1 on the nut portion 10C side to the washer 9 on the bearing plate 7 side. It is comprised so that it may crimp-fix to the convex lower spherical surface part 9c formed in this.

  As described above, in the nut 10 with an anchor cap of the present embodiment, the nut portion 10c is screwed to the head portion 1a of the anchor 1 so that the upper spherical portion 10c1 having a concave shape on the nut portion 10c side is connected to the bearing plate 7. The lower spherical portion 9c having a convex shape formed on the side washer 9 is fixed by crimping. Since the cap cap nut 10a and the nut portion 10c are integrally formed, the anchor cap 10 has a small number of parts and can be easily assembled to the anchor 1 as in the above embodiment. Moreover, the function with respect to the inclination of the anchor 1 is the same as that of the above-described embodiment, and the inner diameter of the cap portion 10a can be made slightly larger than the outer diameter of the head 1a of the anchor 1, so that the use of a rust preventive agent as compared with the prior art The amount can be reduced and it is economical.

  FIG. 7 is an enlarged view showing a main part of the fourth embodiment of the present invention. This embodiment is a modification of the embodiment shown in FIG. 5 and FIG. 6 and has the same basic configuration, in which the washer 8 and the washer 9 are integrally formed. As described above, in this embodiment, the washer 8 and the washer 9 are integrally formed, so that the number of parts is small, and attachment is easy.

  FIG. 8 is an enlarged view showing the main part of the fifth embodiment of the present invention. The basic configuration of this embodiment is the same as that of the embodiment shown in FIGS. 1 to 3, and a recess 7 b in which the head 1 a of the anchor 1 is embedded is provided at the anchor mounting position of the bearing plate 7. The nut 10 with an anchor cap is positioned in the recess 7b. In the case of the present embodiment, the possibility that the head 1a of the anchor 1 or the nut 10 with the cap is damaged due to falling rocks or the like from the upper part is alleviated.

  In the above description of the embodiments, the case where the present invention is applied to an anchor that employs a lock bolt as an anchor has been described as an example. However, as described above, the present invention employs a ground anchor or the like as an anchor, and a sheath. The present invention can also be applied to a type of anchor that is not used. That is, in place of the deformed PC steel rod, the anchor that uses other PC steel material such as PC steel wire or PC steel wire is also compatible with the female screw formed inside the nut with cap for anchor. If so, it can be applied.

It is sectional drawing which showed 1st Example of this invention. It is the enlarged view which showed the principal part of the Example. It is component explanatory drawing which showed the nut with a cap for anchors which concerns on this invention. It is the enlarged view which showed the principal part of 2nd Example of this invention. It is sectional drawing which showed 3rd Example of this invention. It is the enlarged view which showed the principal part of the Example. It is the enlarged view which showed the principal part of 4th Example of this invention. It is the enlarged view which showed the principal part of 5th Example of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Anchor, 7 ... Bearing plate, 8 ... Washer, 9 ... Washer, 10 ... Nut with cap for anchor

Claims (2)

  Provided on the bearing plate side is a lower spherical portion that transmits a tensile force acting on a civil anchor such as a lock bolt to the bearing plate, and an upper spherical portion that can be fitted to the lower spherical portion at the lower portion. A nut having a cap for the anchor, in which a female screw that can be screwed to the anchor is formed and a cap portion that integrally covers the upper portion of the anchor is integrally formed, and a lower portion of the nut with the cap for the anchor An anchor tightening method for civil engineering, wherein the anchor is tightened in a state in which the upper spherical portion formed in the fitting portion is fitted to the lower spherical portion provided on the bearing plate side. The upper spherical surface portion that can be fitted to the lower spherical surface portion formed on the bearing plate side at the lower portion, and a female screw that can be screwed into an anchor for civil engineering such as a lock bolt is formed inside, A nut with an anchor cap for civil engineering, wherein a cap portion covering the upper portion of the anchor is integrally formed.

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