JP6223775B2 - Tubular diagnosis method - Google Patents

Description

  The present invention relates to a method for nondestructively diagnosing the degree of deterioration in a pipe body buried as a sewer, an agricultural waterway or the like.

  Reinforced plastic composite pipes (FRPM pipes) in which glass fiber reinforced plastic (FRP) excellent in tensile strength and resin mortar resistant to compression are laminated may be used as pipes for buried pipes such as sewers and agricultural waterways. .

  Some of these FRPM pipes have passed more than 30 years after being buried, but at present, we cannot grasp qualitatively the degree of aging in the interior, including deterioration over time. In order to prevent such accidents and maintain an appropriate function, a technique for diagnosing the internal deterioration degree of the pipe body in a non-destructive manner is required.

  Here, as an inspection apparatus for diagnosing an internal abnormality of an object, for example, those disclosed in Patent Documents 1 and 2 are known. In these inspection apparatuses, a transmitting antenna that transmits radio waves is approached to one of the subjects, a receiving antenna that receives radio waves is approached to the other, and the radio waves are transmitted into the subject. It is intended to diagnose the presence or absence.

JP 2004-333438 A JP 2010-204055 A

  However, in the above-described inspection apparatus, the object is a target that is relatively easy to be sandwiched between a transmission antenna and a reception antenna such as a stone or a concrete wall. It is extremely difficult to inspect what is installed in a situation where it cannot be sandwiched from inside and outside.

  Accordingly, an object of the present invention is to provide a method capable of easily diagnosing the degree of deterioration inside a pipe body of a buried pipe without causing destruction.

  In order to solve the above-mentioned problem, the present invention attaches a transmitting antenna that transmits radio waves to the end face of a tubular body, and receives the radio waves transmitted from the transmitting antenna and transmitted through the tubular body by the receiving antenna near the inner surface of the tubular body. Diagnosing the degree of internal deterioration of the tubular body by moving the receiving antennas sequentially in the tube axis direction or attaching the receiving antennas at predetermined intervals in the tube axis direction and analyzing the state of the received radio waves. It was.

  In addition, a plurality of the transmission antennas are attached at intervals in the pipe circumferential direction, and the internal deterioration degree of the pipe body is diagnosed over the pipe circumferential direction.

  And as one aspect of this diagnostic method, the transmitting antenna is attached to the end face of one pipe body that appears in the pipe line in the gap of the pipe joint portion that can be a pipe joint that is piped by using an inner surface joining jig. It was.

  Alternatively, the transmitting antenna is attached to the end face of the tubular body that appears in the manhole where the pipes are discontinuous.

  In this method, in a buried pipe, a transmitting antenna is attached to the end face of the tubular body, and the radio wave from the transmitting antenna is received by the receiving antenna located inside the tubular body. Degree can be diagnosed.

The figure which shows the outline of the diagnostic method of the pipe body using the clearance gap of the pipe joint part made into the pipe joint piped using an inner surface joining jig The figure which shows the outline of the diagnostic method of the tubular body using a manhole

  The first embodiment shown in FIG. 1 shows an example of a diagnostic method for a case where the inner diameter of the tube body 1 is 800 mm or more and a human can enter the conduit.

  In a joint of an embedded pipe composed of a pipe body 1 having such a size, generally, an end part 1a of one pipe body 1 to be joined is covered with an enlarged end part 1b of the other pipe body 1. Thus, when piping is performed using an inner surface joining jig, a gap is formed in the pipe joint portion, and the end face of one pipe body 1 appears in the pipe line. Openings such as manholes 2 leading to the ground surface are provided in places on the pipe line of the tube body 1 for maintenance work.

  The inspection device used in this diagnostic method is assumed to include a transmission antenna 11, a reception antenna 12, an oscillator 13, and an analyzer 14. The transmission antenna 11 and the oscillator 13 are connected by a long cable 11a. The receiving antenna 12 and the analyzer 14 can communicate with each other wirelessly or by wire, and an operator brings the accessory antenna 12 and the analyzer 14 together with the accessory.

  In the operation of diagnosing the internal deterioration degree of the pipe body 1 using the inspection apparatus, the oscillator 13 is installed on the ground surface side, the worker enters the pipe line through the manhole 2, and the cable 11 a is connected from the manhole 2. The transmission antenna 11 is attached to the end face of one pipe body 1 that is drawn into the pipe line and appears in the pipe line. The reception antenna 12 is carried by an operator or attached to the inner surface of the pipe line as shown in the figure.

  Here, the number and arrangement of the transmission antennas 11 and the reception antennas 12 are arbitrary, but the plurality of transmission antennas 11 and reception antennas 12 are equally spaced in the tube circumferential direction of the tube 1 in order to improve diagnosis accuracy. It is desirable to install with a gap. The receiving antenna 12 may be attached at a predetermined interval in the tube axis direction.

  In this state, radio waves such as microwaves and millimeter waves are transmitted from the transmission antenna 11, and workers in the pipe travel in the tube axis direction and transmit radio waves transmitted from the transmission antenna 11 and transmitted through the tube body 1. The signal is received by the receiving antenna 12 and the signal is confirmed by the analyzer 14.

  Prior to diagnosing the degree of internal deterioration of the tubular body 1, a new tubular body equivalent to the buried tubular body 1, or before the tubular body 1 is buried, can be processed normally by the same method as this diagnostic method. Secure the data in the correct state.

  Then, by comparing the data measured in the diagnostic work with the data in a normal state acquired in advance, the internal deterioration state of the tubular body 1 is verified over the pipe circumferential direction and the pipe axis direction, It is determined whether or not there is an abnormality such as a void or a crack. When it is judged that there is an abnormality, the integrity of the pipeline can be maintained by carrying out repair work.

  Next, 2nd Embodiment shown in FIG. 2 shows the example of the diagnostic method about the case where the internal diameter of the pipe body 1 is less than 800 mm, and a human cannot enter in a pipe line. Here, only differences from the first embodiment will be described.

  In the case of such a buried pipe, since the pipe line is discontinuous in the manhole 3 leading to the ground surface, an operator enters the manhole 3 and the transmitting antenna 11 is placed on the end face of the tubular body 1 that appears on the inner surface of the manhole 3. Install. The transmitting antenna 11 and the oscillator 13 installed on the ground surface side are connected through a manhole 3 by a cable 11a.

  For example, the receiving antenna 12 is attached to the transport carriage 15 and is fed into the pipe line from the opening facing the manhole 3 of the pipe body 1 or is attached to the inner surface of the pipe line as shown. The transport carriage 15 is equipped with an analyzer 14 or a storage device capable of recording an output signal from the receiving antenna 12.

  Then, the carriage 15 is advanced in the tube axis direction, the radio wave transmitted from the transmission antenna 11 and transmitted through the tube 1 is received by the reception antenna 12, and the output signal from the reception antenna 12 is analyzed by the analyzer 14. Record.

  Thereafter, the transport carriage 15 is collected from the manhole 3, and based on the data recorded in the analyzer 14, the internal deterioration state of the tube body 1 is verified in the pipe circumferential direction and the pipe axis direction. It is determined whether there is an abnormality such as the occurrence of a crack. When it is judged that there is an abnormality, the integrity of the pipeline can be maintained by carrying out repair work.

  The tube to be diagnosed by the method according to each of the embodiments is not limited to the FRPM tube, and the internal degradation degree of the tube is also determined by a similar method for a tube made of other materials such as concrete. Can be diagnosed.

DESCRIPTION OF SYMBOLS 1 Tube 1a, 1b End part 2,3 Manhole 11 Transmission antenna 11a Cable 12 Reception antenna 12a Support rod 13 Oscillator 14 Analyzer 15 Carriage cart

Claims (4)

In order to diagnose the degree of internal deterioration of the pipe body of the buried pipe, a transmission antenna that transmits radio waves is attached to the end face of the pipe body , and the thickness direction increases as the distance from the end face of the pipe body is transmitted from the transmission antenna . Radio waves transmitted from the outer diameter side to the inner diameter side are received by the receiving antenna near the inner surface of the tube, and the receiving antenna is sequentially moved in the tube axis direction, or the receiving antenna is attached at a predetermined interval in the tube axis direction, A tubular body diagnosis method for diagnosing the degree of internal deterioration of a tubular body by analyzing the state of received radio waves.   2. The method of diagnosing a tubular body according to claim 1, wherein a plurality of the transmission antennas are attached at intervals in the circumferential direction of the tube, and the internal deterioration degree of the tubular body is diagnosed over the circumferential direction of the tube.   The transmission antenna is attached to an end surface of one pipe body that appears in a pipe line in a gap of a pipe joint portion that can be a pipe joint that is piped by using an inner surface joining jig. The method for diagnosing a tubular body as described.   The method of diagnosing a tubular body according to claim 1 or 2, wherein the transmitting antenna is attached to an end face of the tubular body that appears in a manhole in which the pipeline is discontinuous.

Images