JPS6161086A - Probing method for radiation absorbing body in structure - Google Patents

Abstract

PURPOSE:To measure an accurate position speedily and easily without any limitation of the shape of an object structure by fitting a block made of a material whose coefficient of absorption to radiation is equal to that of the structure in the projection/recess part of the object structure. CONSTITUTION:The block B made of the material whose coefficient of absorption to radiation is equal to that of the structure 1 is fitted to a corner part 13 of the structure 1; and a marking line 3 is arranged on a marking line installation surface B2 and a film F is installed on a film installation surface B3. Then, X rays are emitted from an X-ray source 5 toward the irradiation source flank 11 of the structure 1 and the surface B2 of the block B. The structure 1 and block B are equal in coefficient of absorption to radiation, so the X rays illuminating the surface 11 and surface B2 are considered to illuminate the united structure surrounded with the surface 11, surface B2, surface B3, and film flank 12. A projection of the marker line 3 and a buried body 2 at the corner 13 is projected on the film F, so their positions and sizes are measured to calculate the position of the buried body 2.

Description

[Detailed description of the invention] 〉〉 Industrial application field The present invention is used to detect (probe) the positions of piping, reinforcing bars, etc. in a structure by irradiating it with radiation, and to search for IIi radiation-absorbing objects in a structure. It is concerned with methods, especially for parts with complex shapes such as columns and beams.

<ff> Conventional technology When conducting seismic diagnosis of existing concrete buildings or remodeling buildings, it is necessary to accurately determine in advance the positions of reinforcing bars and piping installed inside concrete walls, columns, beams, etc. be.

Therefore, conventionally, electromagnetic induction methods and radiation irradiation methods have been devised as a so-called non-destructive method of detecting the position of buried objects buried in concrete bodies, columns, etc. of buildings.

In the electromagnetic induction method, a measuring instrument containing an N magnetic coil is moved while contacting the surface of the wall to be inspected, and the reaction of the magnetic force to the buried object is sensed.

In addition, a method has recently been developed in which the concrete wall of the target object is irradiated with radiation to detect buried objects buried within the structure.

That is, first, a II identification line of known dimensions is pasted on the irradiation surface of a structure where buried objects such as reinforcing bars are immediately installed, and on the other hand, a film that senses the transmitted intensity of radiation is attached to the back surface of the device 1.

Next, radiation is irradiated from the radiation source side to project the buried object and the marker line onto the film placed parallel to the marker line.

Then, the position of the buried object is calculated by actually measuring the relative positional relationship and dimensions of the projected view.

<[7> Problems to be Solved by the Present Invention The above method has the following problems.

(a) The electromagnetic induction method has the disadvantage that the depth and size of the buried object cannot be determined, and the measurement error is large. In places where there are complex structures, measurements and judgments of measured values require highly skilled techniques.

(b) In the method of irradiating with radiation, differences in density occur in the film in areas where pillars, beams, etc. are intricately intertwined.

However, if the marking lines are placed on parallel surfaces such as the front and back surfaces as shown in Fig. 5, the film f cannot be installed on pillar a.
3, when searching for the position of the buried object C at the corner, the adjacent surfaces must be used as the irradiation surface and the film installation surface.

In such a situation, since the installation surface of the film 1' is not parallel to the IJI line, the thickness through which the radiation passes will be different and the image will have shading, making measurement impossible.

The present invention solves the above-mentioned drawbacks, and provides a method for detecting radiation-absorbing objects inside complex structures, which allows for quick and easy measurement of more accurate positions, and enables exploration without being restricted by the shape of the structure. The purpose is to provide

<■> Means for solving the problem In the present invention, a block made of a material with the same absorption coefficient for radiation as the structure is fitted into the uneven portion of the target structure, and the marking body and the radiation are By positioning the film in parallel, the distance between the marker and the film was made uniform, and the image was constructed to prevent shading.

<V> Example Next, one embodiment of the present invention will be described based on the drawings.

(a) Each device used in the present invention (FIG. 1) [Structure] In FIG. 1, a structure 1 is a wall made of concrete or the like, or a column, a beam, or the like.

Due to the structure, it is not possible to install the marking line 3 to be covered later and the radiation film F in parallel on the plan view, for example, in a state where only two sides, the adjacent irradiation source side surface 11 and the film side surface 12, are exposed. It has become.

Furthermore, two of the adjacent irradiation source side surface 11 and film side surface 12
A radiation-absorbing object 2 such as a reinforcing bar is buried in a corner 13 formed by a surface.

1 Block 1B is a Glock made of a material with the same radiation absorption coefficient as Structure 1.

It has four parts B1 that fit into the corner parts 13 formed by the irradiation source side surface 11 and the film side surface 12 of the structure 1.
Let the surface be the sign line installation surface] 32 and the film installation surface B3.

A marker line 3, which will be described later, and a film F for radiation, which will be described later, are attached to the marker line installation surface B2 and the film installation surface B3, respectively.

In addition, a material whose absorption coefficient for radiation is the same as that of structure 1,
For example, in addition to the same concrete as the structure, aluminum, or a liquid such as barium or iodine may be used if the thickness is adjusted to be radiologically equivalent to concrete.

[Sign body] 3 is a wire rod made of lead or tungsten, etc., and is the sign line 3 that acts as a sign body, and is located on the sign line installation surface B of block B.
Attach horizontally to 2.

(For example, the Xta source 5 is used as the radiation source 15, but it is of course possible to use 651 lines other than X-rays.)
be.

The X-ray source 5 is located on the marker line installation surface B2 side of the block B, and a line extending perpendicularly from a point dividing the marker line 3 into three equal parts.
point at an arbitrary distance from the point.

Next, a method of investigating the position of the buried object 2 at the corner 13 of the structure 1 using each of the above devices will be explained.

(a) 1. Fit the block B into the structure 1 by applying the recess B1 of the block 13 to the corner 13 of the installed structure 1.

Then, the marker line 3 is installed horizontally on the marker line installation surface 82, and the filmt is installed on the noilm installation surface B3.

(Irradiation of mouth > xi Next, X-rays are irradiated from the X-ray source 5 toward the irradiation source side surface 11 of the structure 1 and the marker line installation surface 132 of the block B.

(c) State of X-ray transmission Since structure 1 and block 3 have the same radiation absorption rate, The line is the irradiation source side 11, the marker line installation surface B2, the film iQW100B3,
Look at the integral structure surrounded by Noilm side 12 etc.
It will be the same as what happened.

Furthermore, the above I! On the object, two parallel marking lines, a marker line installation surface B2, and a film installation surface 83, are provided with a marker line and a radiation shield F.

Therefore, the film [includes the marker line 3 and the buried object 2 at the corner 13]
A projection of the image is displayed. (Fig. 2) (C) Position i recognition by analysis principle 1 drawing (Fig. 3) The X-ray source 5 set on the drawing is S, and from S, the actually measured 10 ts B marker line installation surface B2 Extend a straight line of distance FWD, and let one end of it be S', and on a line that intersects at right angles to the white line SS-, h from the intersection point is also a distance of half 30 of the marker line (the points at /2 are P, 1, )'.

Next, draw a line connecting the point S where the X-ray source 5 is placed and P and P'.

A straight line connecting the points r and r- on the extension lines of the straight lines SP and SP-, which is parallel to the straight line PP- and whose length is the length L projected on the film F of the marker line 3 is projected. This is the marked line part.

Next, a straight line connecting point tt' on the straight line connecting both ends qq- of the projected view of the buried object 2 appearing in the marker line section obtained above and the irradiation source S, parallel to JIIPP'. A circle whose diameter is the straight line 11', which is the diameter path $1d of the buried object 2, is the buried position of the buried object 2.

(e) Other Examples (Figure 4) In the above example, a wire marker line was used as the marker, but a lead plate N, etc. inserted into the block B and parallel to the film installation surface was used as the marker. It is also possible to use

The point is lj parallel to the film! All you have to do is position the l1 body and irradiate it.

<VJ> Effects of the Invention Since the present invention has been described above, the following effects can be expected.

(b) By fitting the 10 hooks into the corners of the structure, the film and the sign become parallel in plan view.

Therefore, the transmission distance of the radiation becomes uniform, and the image has no shading (
Become.

Therefore, it is possible to search for buried objects even in complex parts such as the corners of columns and beams.

(b) Since the position of an object within a structure is displayed as a clear numerical value, it is much more accurate than electromagnetic induction methods, and it is possible to know the position of buried objects with great skill.

(c) Generally, finishing materials are attached to concrete to give the interior a beautiful finish, but according to the method of the present invention, there is no need to remove or paste such interior materials, and the interior can be left as is. inspection is possible.

(d) Since the pipes, etc. inside the structure are displayed numerically, the reinforcing condition of the structure can be clearly seen, making it possible to improve the efficiency of safety inspections to confirm seismic performance.

[Brief explanation of drawings]

Figure 1: Perspective view of one embodiment of the present defense Figure 2: Plan view during irradiation

Claims (1)

[Claims] A block is used that is made of a material with the same radiation absorption coefficient as the structure and has a shape that fits into the corner of the structure, and a marker with known dimensions and a radiation source are placed on each side of this block. The block is fitted to the corner of the structure, radiation is irradiated from the side where the marker line is attached, and the position and dimensions of the marker line and the radiation absorbing object projected on the film are measured. A method for searching for a radiation-absorbing object in a structure, the method comprising: actually measuring and calculating the position of the buried radiation-absorbing object.