Surveying jig

Abstract

To solve the problems of prior arts, that is, to provide a surveying jig capable of being more easily installed on the tip of an anchor bolt than the prior arts.SOLUTION: A surveying jig of the present invention is a jig that is installed at the tip of an anchor bolt embedded in concrete, and comprises an anchor-side member and a marker-side member. The anchor-side member has an insertion hole penetrating in an axial direction, and the marker-side member has a housing hole that is surrounded by a lower surface of a pedestal body and an inner surface of a wall body. When the anchor-side member is attached to the marker-side member by housing an outer insert in the housing hole, and the anchor bolt is inserted into the insertion hole until the tip of the anchor bolt abuts against a magnet, the marker-side member is fixed to the anchor bolt.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a technique relating to a surveying jig, and more specifically to a surveying jig capable of surveying the tip of an anchor bolt embedded in concrete. [Background technology]

[0002] A bridge is primarily composed of substructures such as abutments and piers, and superstructures such as main girders and decks. The superstructure is generally made of concrete or steel, while the substructure is generally made of reinforced concrete (RC), which contains reinforcing bars inside.

[0003] Incidentally, there are cases where equipment is retroactively installed on bridges that are already in service. For example, a "displacement limiting device" is installed to restrict displacement of the superstructure, a "bridge fall prevention device" is installed to prevent the superstructure from falling, or a reaction frame is installed to jack up the deck during bearing replacement work. Typically, in such construction work, so-called "post-installed anchor bolts" are embedded in the reinforced concrete bridge piers, and then brackets are attached using the post-installed anchor bolts, and then the displacement limiting device or other equipment is installed.

[0004] Brackets to be attached to bridge piers, etc. are manufactured in a factory, at which time bolt holes are made for the insertion of post-installed anchor bolts. On the other hand, post-installed anchor bolts are naturally installed on-site, and are basically embedded in bridge piers, etc., at the planned position. However, when drilling holes in reinforced concrete structures (for example, bridge piers) for post-installed anchor bolts, it is possible that main reinforcement or distribution reinforcement bars are located in unexpected positions, in which case the position must be changed before drilling the holes so as not to interfere with the main reinforcement, etc. In this way, the position at which post-installed anchor bolts are embedded is often not as planned, and for this reason, the current practice is to survey the embedded post-installed anchor bolts to obtain the coordinates of their tips before drilling the bolt holes in the brackets.

[0005] Previously, surveying of post-installed anchor bolts was done manually by surveyors. Specifically, the planned positions of the post-installed anchor bolts were marked on the surface of the reinforced concrete wall with a marking cross, and the difference between the intersection of the marking cross and the actual position of the post-installed anchor bolt was measured using a ruler or similar. However, this manual measurement method had problems in that the measurement accuracy varied depending on the experience and skill of the surveyor, transcription errors could occur when recording the results of on-site measurements using a ruler or similar in a field notebook, and in the first place, manually measuring all post-installed anchor bolts required a long measurement time and considerable effort.

[0006] Therefore, various improved techniques for measuring the position of post-installed anchor bolts have been proposed. For example, Patent Document 1 proposes a technique for acquiring the position coordinates of a post-installed anchor bolt by installing a measuring jig at the tip of the post-installed anchor bolt and performing photogrammetry using a marker plate of the measuring jig. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-121450 Summary of the Invention [Problem to be solved by the invention]

[0008] The technology disclosed in Patent Document 1 involves attaching a measuring jig to an anchor bolt by screwing a female thread on the measuring jig into a male thread on the tip of the anchor bolt, and acquiring the position coordinates of the anchor bolt by photographing a marker plate attached to the measuring jig. This technology provides more stable measurement accuracy than conventional manual measurement, prevents human errors such as transcription errors, and reduces the time and effort required for measurement.

[0009] However, the work of screwing the measuring jig onto the tip of the anchor bolt is still a manual task that requires a certain amount of time and effort, and performing this work on all anchor bolts would require a considerable amount of work time and effort. Also, if the male thread of the anchor bolt is not cured, it is possible that mortar or debris is stuck in the male thread, in which case work must be done to remove the mortar, etc., which in some cases may make it difficult to screw it in. On the other hand, if the male thread of the anchor bolt is cured, the work of removing the curing is required to screw in the measuring jig, and then curing it again after measurement, which requires work time and effort.

[0010] An object of the present invention is to solve the problems of the prior art, that is, to provide a surveying jig that can be more easily installed on the tip of an anchor bolt than the prior art. [Means for solving the problem]

[0011] The present invention was made with a focus on the fact that a surveying jig is fixed to an anchor bolt by magnetically attaching the anchor bolt to a magnet attached to the top surface of the "receiving hole" that receives the tip of the anchor bolt, and is an invention based on an unprecedented idea.

[0012] The surveying jig of the present invention is a jig to be installed at the tip of an anchor bolt embedded in concrete, and includes an anchor-side member and a marker-side member. The anchor-side member comprises a cylindrical outer shell and a flange extending from the outer shell, while the marker-side member comprises a base and a wall. The anchor-side member has an insertion hole penetrating it in the axial direction, and a steel plate is attached to the upper surface of the base and a magnet is attached to the lower surface of the base. The marker-side member also has a receiving hole surrounded by the lower surface of the base and the inner surface of the wall. The anchor-side member is attached to the marker-side member by receiving the outer shell in the receiving hole, and the anchor bolt is inserted into the insertion hole until its tip abuts against the magnet, thereby fixing the marker-side member to the anchor bolt. This allows the coordinates of the anchor bolt's tip to be measured using a magnetic survey marker magnetically attached to the steel plate.

[0013] The surveying jig of the present invention can also be a combination of one marker-side member and two or more anchor-side members. However, the two or more anchor-side members each have an outer insert body with approximately the same (including the same) outer diameter, and an insertion hole with a different inner diameter. This makes it possible to select an appropriate anchor-side member to be attached to the marker-side member depending on the diameter of the anchor bolt.

[0014] The surveying tool of the present invention may further include a guide wall arranged to surround the steel plate. In this case, the survey marker can be magnetically attached to the steel plate while being guided by the guide wall.

[0015] The surveying jig of the present invention may further include a tightening bolt that is threaded into a bolt hole that penetrates the wall. In this case, the anchor-side member can be fixed to the marker-side member by tightening the tightening bolt with the outer shell housed in the housing hole.

[0016] The surveying jig of the present invention may further comprise a suspending ring attached to the sign-side member. In this case, when the sign-side member is fixed to the anchor bolt, the suspending ring can be lifted with a beam to prevent the sign-side member from falling. [Effects of the Invention]

[0017] The surveying jig of the present invention has the following effects. (1) Compared to conventional manual measurements, measurement accuracy is stable and human errors such as transcription errors can be prevented. (2) Furthermore, compared to conventional manual measurement, the time and effort required for measurement can be reduced. (3) Furthermore, compared to the technology disclosed in Patent Document 1, the manual work of screwing into the tip of the anchor bolt is not required, so the work time and labor can be reduced. (4) Depending on the curing method, the curing can be fixed to the anchor bolt without removing it, and at least there is no need to remove mortar or the like from the threaded part to measure the anchor bolt. [Brief explanation of the drawings]

[0018] [Figure 1] 1A is a cross-sectional view showing a schematic diagram of a surveying jig in a disassembled state before being attached to an anchor bolt, and FIG. 1B is a cross-sectional view showing a schematic diagram of the surveying jig fixed to an anchor bolt. [Figure 2] Front view showing a magnetic survey marker. [Figure 3] FIG. 2A is a plan view schematically showing the anchor-side member, and FIG. 2B is a cross-sectional view taken along the line AA of the anchor-side member. [Figure 4] FIG. 4A is a plan view schematically showing the sign-side member, and FIG. 4B is a cross-sectional view taken along the line BB of the sign-side member. [Figure 5] 1A is a cross-sectional view showing a tightening bolt, a bolt hole, and a sign-side member, and FIG. 1B is a cross-sectional view showing an anchor-side member attached to the sign-side member using a tightening bolt. [Figure 6](a) is a cross-sectional view showing a schematic diagram of a surveying jig with a suspending ring attached to a sign side member, and (b) is a cross-sectional view showing a schematic diagram of a surveying jig suspended by a suspending ring. [Figure 7] A cross-sectional view showing a "surveying jig set" consisting of a combination of one sign-side component and three types of anchor-side components. [Figure 8] (a) is a plan view showing a schematic diagram of a "standalone surveying jig" consisting of only the sign-side component, and (b) is a cross-sectional view taken along the CC arrow showing a schematic diagram of a "standalone surveying jig" consisting of only the sign-side component. DETAILED DESCRIPTION OF THE INVENTION

[0019] An example of an embodiment of the surveying jig of the present invention will be described with reference to the drawings.

[0020] 1 is a diagram for explaining an overview of the surveying jig 100 of the present invention, where (a) is a cross-sectional view schematically showing the surveying jig 100 in a disassembled state before being attached to an anchor bolt AB, and (b) is a cross-sectional view schematically showing the surveying jig 100 in a state fixed to the anchor bolt AB. As shown in this figure, the surveying jig 100 of the present invention is fixed to the tip of an anchor bolt AB embedded in a concrete structure CO, and therefore a part of the anchor bolt AB in question protrudes from the surface of the concrete structure CO.

[0021] The surveying jig 100 of the present invention is configured to include an "anchor-side member 200" and a "signature-side member 300" that are formed as separate bodies, and the anchor-side member 200 is attached to the sign-side member 300 and then fixed to the tip of the anchor bolt AB. A bottomed accommodation hole 330 that accommodates a part of the anchor-side member 200 (an extrapolated body 210, described later) is formed in the sign-side member 300, and one of the anchor-side members 200 has an insertion hole 230 that penetrates in the axial direction (i.e., the hole axis direction). As a result, the anchor-side member 200 is attached to the sign-side member 300 by accommodating a part of the anchor-side member 200 in the accommodation hole 330, and the anchor bolt AB can be inserted into the insertion hole 230 to fit the surveying jig 100 (the anchor-side member 200 and the sign-side member 300) onto the tip of the anchor bolt AB. Then, the magnet 312 attached inside the receiving hole 330 and the tip of the anchor bolt AB are magnetically attracted to each other, whereby the surveying jig 100 (particularly the sign-side member 300) is fixed to the anchor bolt AB.

[0022] As shown in Fig. 1, a steel plate 311 is attached to the surface of the sign side component 300, for example, with an adhesive, and this steel plate 311 can be used to magnetically attach a plate-shaped magnetic survey marker TG as shown in Fig. 2. The survey marker TG can be a so-called target used in conventional photogrammetry, and by photographing this with a digital camera or the like, it is possible to determine information (such as an identifier) ​​that can identify the survey marker TG and its center position. Then, by performing photogrammetry using the survey marker TG, it is possible to determine the three-dimensional coordinates of the center of the survey marker TG, that is, the three-dimensional coordinates of the tip of the anchor bolt AB can be obtained.

[0023] Below, each of the main elements constituting the surveying jig 100 of the present invention will be described in detail.

[0024] (Anchor side component) FIG. 3 is a schematic diagram of the anchor-side member 200, where (a) is a plan view from above and (b) is a cross-sectional view taken along the line AA. As shown in this figure, the anchor-side member 200 includes a cylindrical outer member 210 and a plate-like flange 220. The flange 220 is provided so as to protrude outward from the end of the outer member 210 on the anchor bolt AB side (the lower side in FIG. 3(b)). The outer member 210 and the plate-like flange 220 are formed as a single unit and can be made of resin such as polyvinyl chloride. While the flange 220 shown in FIG. 3 has an octagonal planar shape, it is not limited to this and can have any planar shape, such as a circle or a hexagon.

[0025] An insertion hole 230 is formed in the anchor-side member 200, penetrating it in the axial direction. Because an anchor bolt AB is inserted into this insertion hole 230, it is preferable to form the insertion hole 230 with an inner diameter slightly larger than the outer diameter of the anchor bolt AB to be inserted. In addition, a band-shaped outer circumferential groove 211 that is slightly recessed from the rest of the surface can be formed in the outer circumferential surface of the outer fitting body 210, and the tip of a clamping bolt 351, which will be described later, can abut against this outer circumferential groove 211.

[0026] (Sign side component) 4 is a schematic diagram of the sign-side member 300, where (a) is a plan view from above and (b) is a cross-sectional view taken along the line BB. As shown in this figure, the sign-side member 300 is mainly composed of a plate-shaped base body 310 and a cylindrical wall body 320, and can also be composed of a guide wall 340. The base body 310, wall body 320, and guide wall 340 are formed as a single unit and, like the anchor-side member 200, can be made of a resin such as polyvinyl chloride.

[0027] The base 310 has an outer shape that is, for example, a solid, roughly cylindrical shape. The tips of the anchor bolts AB abut against one of its two surfaces (hereinafter referred to as the "lower surface"), and a steel plate 311, which is a steel plate material, is attached to the other surface (hereinafter referred to as the "upper surface"). As described above, by using this steel plate 311, a magnetic survey marker TG as shown in FIG. 2 can be installed by magnetic attachment. Photogrammetry is performed to determine the three-dimensional coordinates of the centers of the survey markers TG, which in turn determine the three-dimensional coordinates of the tips of the anchor bolts AB. To do this, it is desirable to position the survey marker TG so that the centers of the anchor bolts AB and the survey marker TG roughly coincide. Therefore, it is preferable to arrange multiple (four in the figure) guide walls 340 on the base 310 so that they rise from its upper surface and surround the steel plate 311. The position of the survey marker TG, which is guided by these guide walls 340, is forcibly determined; that is, the survey marker TG is positioned so that the centers of the anchor bolt AB and the survey marker TG roughly coincide.

[0028] An accommodation hole 330 that accommodates the extrapolation body 210 of the anchor-side member 200 is formed inside the wall body 320. More specifically, the accommodation hole 330 is a bottomed space that is surrounded by the inner surface of the wall body 320 and has a bottom that coincides with the lower surface of the base body 310. Since the extrapolation body 210 is accommodated in this accommodation hole 330, it is preferable to form the accommodation hole 330 with an inner diameter that is slightly larger than the outer diameter of the extrapolation body 210.

[0029] A slight recess is formed in the center of the underside of base 310, and magnet 312 is attached to wall 320 while housed in this recess. This magnet 312 can be, for example, a neodymium magnet, but any of a variety of conventional magnets can be used as long as they are magnetically attracted to anchor bolt AB. Magnet 312 can be attached to the underside of base 310 using screws 313 as shown in Figure 4(b), or by any of a variety of conventional methods, such as adhesive bonding.

[0030] As described above, the anchor-side member 200 is attached to the sign-side member 300 by accommodating the outer insert 210 in the accommodation hole 330. At this time, it is desirable to configure the anchor-side member 200 so that it does not come off the sign-side member 300. Therefore, as shown in Fig. 5, it is preferable to attach the anchor-side member 200 to the sign-side member 300 using a tightening bolt 351. Fig. 5(a) is a cross-sectional view schematically showing the tightening bolt 351, the bolt hole 352, and the sign-side member 300, and Fig. 5(b) is a cross-sectional view schematically showing the anchor-side member 200 attached to the sign-side member 300 using the tightening bolt 351.

[0031] The tightening bolt 351 is threaded into a bolt hole 352 that penetrates the wall 320 of the sign-side member 300. Therefore, a thread is formed on the inner peripheral surface of the bolt hole 352. When the tightening bolt 351 is tightened with the outer casing 210 housed in the housing hole 330, the outer surface of the outer casing 210 is pressed against the tightening bolt 351, thereby firmly attaching the anchor-side member 200 to the sign-side member 300. If an outer peripheral groove 211 is formed in the outer casing 210, the tip of the tightening bolt 351 can be brought into contact with this groove 211. The axial force of the tightening bolt 351 presses down on the outer casing 210, and this advantageously prevents the outer casing 210 from shifting in the direction perpendicular to the axis of the tightening bolt 351 (the vertical direction in FIG. 5(b)). Although Figure 5 shows a sign side member 300 in which one tightening bolt 351 is threaded into the bolt hole 352, this is not limited to this, and the sign side member 300 can also have two or more tightening bolts 351 threaded into the bolt hole 352.

[0032] The surveying jig 100, in which the anchor-side member 200 is attached to the sign-side member 300, is fixed to the anchor bolt AB by magnetically attracting the tip of the anchor bolt AB to the magnet 312. However, it is conceivable that the surveying jig 100 may fall off the anchor bolt AB due to an unforeseen event such as a strong wind. In this case, if the surveying jig 100 is in a low place that is within reach of a person, it is not particularly difficult to re-fix the surveying jig 100 to the anchor bolt AB. On the other hand, if the target is an anchor bolt AB installed at a high place, it is necessary to prepare a high-altitude work vehicle or set up new scaffolding, and it would take considerable cost and time to re-fix the surveying jig 100 to the anchor bolt AB.

[0033] Therefore, as shown in FIG. 6, it is advisable to attach a suspending ring 360 to the sign-side member 300 to prevent it from falling. FIG. 6(a) is a cross-sectional view schematically showing the surveying jig 100 with the suspending ring 360 attached to the sign-side member 300, and FIG. 6(b) is a cross-sectional view schematically showing the surveying jig 100 with the workpiece WR hoisted via the suspending ring 360. As shown in this figure, the suspending ring 360 has a ring portion formed thereon for connecting the workpiece WR, such as a wire rope, and can be attached to, for example, a base 310. As shown in FIG. 6(b), when the surveying jig 100 is magnetically fixed to the anchor bolt AB, the lower end of the workpiece WR hanging from above is connected to the suspending ring 360. This prevents the surveying jig 100 from falling to the ground even if it unexpectedly falls off the anchor bolt AB, and the surveying jig 100 can be easily re-fixed to the anchor bolt AB.

[0034] (Surveying jig set) The insertion hole 230 of the anchor-side member 200 is formed with an inner diameter slightly larger than the outer diameter of the anchor bolt AB to be fitted. However, the outer diameters of commonly used anchor bolts AB vary widely, including 27 mm, 29 mm, 33 mm, 36 mm, 39 mm, and 48 mm. For this reason, it is desirable to prepare a plurality of types of anchor-side members 200 corresponding to the anchor bolts AB, in other words, it is desirable to prepare a plurality of types of anchor-side members 200 having insertion holes 230 corresponding to the outer diameters of the anchor bolts AB.

[0035] In contrast, the inner diameter of the accommodation hole 330 of the sign-side member 300 is sufficient to accommodate the outer insert 210, and does not need to correspond to the outer diameter of the anchor bolt AB. Therefore, it is advisable to prepare a set of surveying jigs 100 (hereinafter simply referred to as a "surveying jig set") consisting of a combination of one sign-side member 300 and two or more anchor-side members 200. However, the two or more anchor-side members 200 constituting the surveying jig set each have an outer insert 210 with approximately the same (including the same) outer diameter, and each have an insertion hole 230 with a different inner diameter. Of course, the accommodation hole 330 of the sign-side member 300 is formed with an inner diameter slightly larger than the outer diameter of the outer insert 210 of the two or more anchor-side members 200. For example, FIG. 7 shows a surveying jig set consisting of a combination of one sign-side member 300 and three types of anchor-side members 200A to 200C, each with an insertion hole 230 with different inner diameters. This makes it possible to appropriately select the anchor-side member 200 to be attached to the sign-side member 300 depending on the outer diameter of the target anchor bolt AB.

[0036] (Single-type surveying jig) So far, we have described the surveying jig 100 consisting of the anchor-side member 200 and the marker-side member 300. However, the surveying jig 100 of the present invention can also be configured to consist only of the marker-side member 300 (hereinafter referred to as a "standalone surveying jig"). Figure 8 is a schematic diagram of a standalone surveying jig, with (a) a plan view from above and (b) a cross-sectional view taken along the CC arrow. As shown in this figure, the standalone surveying jig has roughly the same configuration as the marker-side member 300. However, instead of the outer insert 210 of the anchor-side member 200, the anchor bolt AB is directly inserted into the receiving hole 330. Therefore, it is preferable to form the insertion hole 230 with an inner diameter slightly larger than the outer diameter of the anchor bolt AB. Since the standalone surveying jig does not have the anchor-side member 200, it does not have the tightening bolt 351 or bolt hole 352, but it can have a hanging ring 360. [Industrial Applicability]

[0037] The surveying jig of the present invention can be used for various concrete structures, including bridges, concrete retaining walls, concrete dams, tunnel lining concrete, etc. Considering that the present invention can efficiently install equipment such as bridge collapse prevention devices and ultimately extend the life of social capital (infrastructure), it can be said to be an invention that can be expected to not only be used industrially but also make a great contribution to society. [Explanation of symbols]

[0038] 100 Surveying jig of the present invention 200 Anchor side member (of surveying jig) 210 (Anchor side member) extrapolation body 211 (extrapolated body) peripheral groove 220 (Anchor side member) flange 230 (Anchor side member) insertion hole 300 (Surveying jig) sign side member 310 (Sign side component) base 311 (Base) Steel Plate 312 (Base) Magnet 313 (Base) Screw 320 (Sign-side member) wall 330 (Sign side member) receiving hole 340 Guide wall (of sign side member) 351 (surveying jig) tightening bolt 352 (surveying jig) bolt hole 360 (surveying jig) hanging ring AB anchor bolt CO concrete structures TG survey sign WR strategy material

Claims

1. A jig to be installed at the tip of an anchor bolt embedded in concrete, an anchor side member consisting of a cylindrical outer shell and a flange extending from the outer shell; a sign-side member consisting of a base body and a wall body; The anchor-side member has an insertion hole formed therethrough in the axial direction, a steel plate is attached to the upper surface of the base body, and a magnet is attached to the lower surface of the base body; The sign-side member has a receiving hole formed therein and surrounded by a lower surface of the base body and an inner surface of the wall body, The anchor-side member is attached to the sign-side member by accommodating the outer insert in the accommodation hole, and when the anchor bolt is inserted into the insertion hole until the tip of the anchor bolt abuts against the magnet, the sign-side member is fixed to the anchor bolt, and the coordinates of the tip of the anchor bolt can be measured using a magnetic survey marker magnetically attached to the steel plate. A surveying jig characterized by:

2. The tag-side member is a combination of one tag-side member and two or more anchor-side members, The two or more anchor-side members are each formed with the outer insert body having the same or approximately the same outer diameter, and the insertion holes are each formed with different inner diameters, The anchor-side member to be attached to the sign-side member can be selected depending on the diameter of the anchor bolt.

2. The surveying jig according to claim 1.

3. Further provided is a guide wall arranged to surround the steel plate, The survey marker can be magnetically attached to the steel plate while being guided by the guide wall.

2. The surveying jig according to claim 1.

4. Further provided is a fastening bolt that is screwed into a bolt hole that penetrates the wall body, When the fastening bolt is tightened with the outer insert housed in the housing hole, the anchor-side member is fixed to the marker-side member.

2. The surveying jig according to claim 1.

5. Further provided is a hanging ring attached to the sign side member, When the sign-side member is fixed to the anchor bolt, the hanging ring body can be lifted with a rope to prevent the sign-side member from falling.

2. The surveying jig according to claim 1.

Images